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gnu / binutils-gdb / 4ea28692e88cdc4ff5d80f486bfd9ba7a78b5cc7 / . / gdb / dwarf2 / read.c
blob: b9040a57cf962e9b04921aad4ed27dc767cc8e00 [file] [log] [blame]
/* DWARF 2 debugging format support for GDB.
Copyright (C) 1994-2024 Free Software Foundation, Inc.
Adapted by Gary Funck (gary@intrepid.com), Intrepid Technology,
Inc. with support from Florida State University (under contract
with the Ada Joint Program Office), and Silicon Graphics, Inc.
Initial contribution by Brent Benson, Harris Computer Systems, Inc.,
based on Fred Fish's (Cygnus Support) implementation of DWARF 1
support.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* FIXME: Various die-reading functions need to be more careful with
reading off the end of the section. */
#include "dwarf2/read.h"
#include "dwarf2/abbrev.h"
#include "dwarf2/aranges.h"
#include "dwarf2/attribute.h"
#include "dwarf2/comp-unit-head.h"
#include "dwarf2/cooked-index-storage.h"
#include "dwarf2/cooked-indexer.h"
#include "dwarf2/cu.h"
#include "dwarf2/index-cache.h"
#include "dwarf2/leb.h"
#include "dwarf2/line-header.h"
#include "dwarf2/dwz.h"
#include "dwarf2/macro.h"
#include "dwarf2/die.h"
#include "dwarf2/read-debug-names.h"
#include "dwarf2/read-gdb-index.h"
#include "dwarf2/sect-names.h"
#include "dwarf2/stringify.h"
#include "dwarf2/tag.h"
#include "dwarf2/public.h"
#include "bfd.h"
#include "elf-bfd.h"
#include "event-top.h"
#include "exceptions.h"
#include "gdbsupport/task-group.h"
#include "symtab.h"
#include "gdbtypes.h"
#include "objfiles.h"
#include "dwarf2.h"
#include "demangle.h"
#include "gdb-demangle.h"
#include "filenames.h"
#include "language.h"
#include "complaints.h"
#include "dwarf2/expr.h"
#include "dwarf2/loc.h"
#include "cp-support.h"
#include "hashtab.h"
#include "command.h"
#include "cli/cli-cmds.h"
#include "block.h"
#include "addrmap.h"
#include "typeprint.h"
#include "c-lang.h"
#include "go-lang.h"
#include "valprint.h"
#include "gdbcore.h"
#include "gdb_bfd.h"
#include "f-lang.h"
#include "source.h"
#include "build-id.h"
#include "namespace.h"
#include "gdbsupport/function-view.h"
#include <optional>
#include "gdbsupport/underlying.h"
#include "filename-seen-cache.h"
#include <fcntl.h>
#include <algorithm>
#include "gdbsupport/selftest.h"
#include "rust-lang.h"
#include "gdbsupport/pathstuff.h"
#include "count-one-bits.h"
#include "dwarf2/abbrev-table-cache.h"
#include "cooked-index.h"
#include "gdbsupport/thread-pool.h"
#include "run-on-main-thread.h"
#include "dwarf2/parent-map.h"
#include "dwarf2/error.h"
#include "gdbsupport/unordered_set.h"
#include "extract-store-integer.h"
/* When == 1, print basic high level tracing messages.
When > 1, be more verbose.
This is in contrast to the low level DIE reading of dwarf_die_debug. */
static unsigned int dwarf_read_debug = 0;
/* Print a "dwarf-read" debug statement if dwarf_read_debug is >= 1. */
#define dwarf_read_debug_printf(fmt, ...) \
debug_prefixed_printf_cond (dwarf_read_debug >= 1, "dwarf-read", fmt, \
##__VA_ARGS__)
/* Print a "dwarf-read" debug statement if dwarf_read_debug is >= 2. */
#define dwarf_read_debug_printf_v(fmt, ...) \
debug_prefixed_printf_cond (dwarf_read_debug >= 2, "dwarf-read", fmt, \
##__VA_ARGS__)
/* Print "dwarf-read" start/end debug statements. */
#define DWARF_READ_SCOPED_DEBUG_START_END(fmt, ...) \
scoped_debug_start_end ([] { return dwarf_read_debug >= 1; }, "dwarf-read", \
fmt, ##__VA_ARGS__)
/* When non-zero, dump DIEs after they are read in. */
static unsigned int dwarf_die_debug = 0;
/* When non-zero, dump line number entries as they are read in. */
unsigned int dwarf_line_debug = 0;
/* When true, cross-check physname against demangler. */
static bool check_physname = false;
/* This is used to store the data that is always per objfile. */
static const registry<objfile>::key<dwarf2_per_objfile>
dwarf2_objfile_data_key;
/* These are used to store the dwarf2_per_bfd objects.
objfiles having the same BFD, which doesn't require relocations, are going to
share a dwarf2_per_bfd object, which is held in the _bfd_data_key version.
Other objfiles are not going to share a dwarf2_per_bfd with any other
objfiles, so they'll have their own version kept in the _objfile_data_key
version. */
static const registry<bfd>::key<dwarf2_per_bfd> dwarf2_per_bfd_bfd_data_key;
static const registry<objfile>::key<dwarf2_per_bfd>
dwarf2_per_bfd_objfile_data_key;
/* The "aclass" indices for various kinds of computed DWARF symbols. */
static int dwarf2_locexpr_index;
static int dwarf2_loclist_index;
static int ada_imported_index;
static int dwarf2_locexpr_block_index;
static int dwarf2_loclist_block_index;
static int ada_block_index;
/* Size of .debug_loclists section header for 32-bit DWARF format. */
#define LOCLIST_HEADER_SIZE32 12
/* Size of .debug_loclists section header for 64-bit DWARF format. */
#define LOCLIST_HEADER_SIZE64 20
/* Size of .debug_rnglists section header for 32-bit DWARF format. */
#define RNGLIST_HEADER_SIZE32 12
/* Size of .debug_rnglists section header for 64-bit DWARF format. */
#define RNGLIST_HEADER_SIZE64 20
/* See dwarf2/read.h. */
dwarf2_per_objfile *
get_dwarf2_per_objfile (struct objfile *objfile)
{
return dwarf2_objfile_data_key.get (objfile);
}
/* Default names of the debugging sections. */
/* Note that if the debugging section has been compressed, it might
have a name like .zdebug_info. */
const struct dwarf2_debug_sections dwarf2_elf_names =
{
{ ".debug_info", ".zdebug_info" },
{ ".debug_abbrev", ".zdebug_abbrev" },
{ ".debug_line", ".zdebug_line" },
{ ".debug_loc", ".zdebug_loc" },
{ ".debug_loclists", ".zdebug_loclists" },
{ ".debug_macinfo", ".zdebug_macinfo" },
{ ".debug_macro", ".zdebug_macro" },
{ ".debug_str", ".zdebug_str" },
{ ".debug_str_offsets", ".zdebug_str_offsets" },
{ ".debug_line_str", ".zdebug_line_str" },
{ ".debug_ranges", ".zdebug_ranges" },
{ ".debug_rnglists", ".zdebug_rnglists" },
{ ".debug_types", ".zdebug_types" },
{ ".debug_addr", ".zdebug_addr" },
{ ".debug_frame", ".zdebug_frame" },
{ ".eh_frame", NULL },
{ ".gdb_index", ".zgdb_index" },
{ ".debug_names", ".zdebug_names" },
{ ".debug_aranges", ".zdebug_aranges" },
23
};
/* List of DWO/DWP sections. */
static const struct dwop_section_names
{
struct dwarf2_section_names abbrev_dwo;
struct dwarf2_section_names info_dwo;
struct dwarf2_section_names line_dwo;
struct dwarf2_section_names loc_dwo;
struct dwarf2_section_names loclists_dwo;
struct dwarf2_section_names macinfo_dwo;
struct dwarf2_section_names macro_dwo;
struct dwarf2_section_names rnglists_dwo;
struct dwarf2_section_names str_dwo;
struct dwarf2_section_names str_offsets_dwo;
struct dwarf2_section_names types_dwo;
struct dwarf2_section_names cu_index;
struct dwarf2_section_names tu_index;
}
dwop_section_names =
{
{ ".debug_abbrev.dwo", ".zdebug_abbrev.dwo" },
{ ".debug_info.dwo", ".zdebug_info.dwo" },
{ ".debug_line.dwo", ".zdebug_line.dwo" },
{ ".debug_loc.dwo", ".zdebug_loc.dwo" },
{ ".debug_loclists.dwo", ".zdebug_loclists.dwo" },
{ ".debug_macinfo.dwo", ".zdebug_macinfo.dwo" },
{ ".debug_macro.dwo", ".zdebug_macro.dwo" },
{ ".debug_rnglists.dwo", ".zdebug_rnglists.dwo" },
{ ".debug_str.dwo", ".zdebug_str.dwo" },
{ ".debug_str_offsets.dwo", ".zdebug_str_offsets.dwo" },
{ ".debug_types.dwo", ".zdebug_types.dwo" },
{ ".debug_cu_index", ".zdebug_cu_index" },
{ ".debug_tu_index", ".zdebug_tu_index" },
};
/* local data types */
/* The location list and range list sections (.debug_loclists & .debug_rnglists)
begin with a header, which contains the following information. */
struct loclists_rnglists_header
{
/* A 4-byte or 12-byte length containing the length of the
set of entries for this compilation unit, not including the
length field itself. */
unsigned int length;
/* A 2-byte version identifier. */
short version;
/* A 1-byte unsigned integer containing the size in bytes of an address on
the target system. */
unsigned char addr_size;
/* A 1-byte unsigned integer containing the size in bytes of a segment selector
on the target system. */
unsigned char segment_collector_size;
/* A 4-byte count of the number of offsets that follow the header. */
unsigned int offset_entry_count;
};
/* These sections are what may appear in a (real or virtual) DWO file. */
struct dwo_sections
{
struct dwarf2_section_info abbrev;
struct dwarf2_section_info line;
struct dwarf2_section_info loc;
struct dwarf2_section_info loclists;
struct dwarf2_section_info macinfo;
struct dwarf2_section_info macro;
struct dwarf2_section_info rnglists;
struct dwarf2_section_info str;
struct dwarf2_section_info str_offsets;
/* In the case of a virtual DWO file, these two are unused. */
struct dwarf2_section_info info;
std::vector<dwarf2_section_info> types;
};
/* CUs/TUs in DWP/DWO files. */
struct dwo_unit
{
/* Backlink to the containing struct dwo_file. */
struct dwo_file *dwo_file;
/* The "id" that distinguishes this CU/TU.
.debug_info calls this "dwo_id", .debug_types calls this "signature".
Since signatures came first, we stick with it for consistency. */
ULONGEST signature;
/* The section this CU/TU lives in, in the DWO file. */
struct dwarf2_section_info *section;
/* Same as dwarf2_per_cu::{sect_off,length} but in the DWO section. */
sect_offset sect_off;
unsigned int length;
/* For types, offset in the type's DIE of the type defined by this TU. */
cu_offset type_offset_in_tu;
};
/* Hash function for dwo_unit objects, based on the signature. */
struct dwo_unit_hash
{
using is_transparent = void;
std::size_t operator() (ULONGEST signature) const noexcept
{ return signature; }
std::size_t operator() (const dwo_unit *unit) const noexcept
{ return (*this) (unit->signature); }
};
/* Equal function for dwo_unit objects, based on the signature.
The signature is assumed to be unique within the DWO file. So while object
file CU dwo_id's always have the value zero, that's OK, assuming each object
file DWO file has only one CU, and that's the rule for now. */
struct dwo_unit_eq
{
using is_transparent = void;
bool operator() (ULONGEST sig, const dwo_unit *unit) const noexcept
{ return sig == unit->signature; }
bool operator() (const dwo_unit *a, const dwo_unit *b) const noexcept
{ return (*this) (a->signature, b); }
};
/* Set of dwo_unit object, using their signature as identity. */
using dwo_unit_set = gdb::unordered_set<dwo_unit *, dwo_unit_hash, dwo_unit_eq>;
/* include/dwarf2.h defines the DWP section codes.
It defines a max value but it doesn't define a min value, which we
use for error checking, so provide one. */
enum dwp_v2_section_ids
{
DW_SECT_MIN = 1
};
/* Data for one DWO file.
This includes virtual DWO files (a virtual DWO file is a DWO file as it
appears in a DWP file). DWP files don't really have DWO files per se -
comdat folding of types "loses" the DWO file they came from, and from
a high level view DWP files appear to contain a mass of random types.
However, to maintain consistency with the non-DWP case we pretend DWP
files contain virtual DWO files, and we assign each TU with one virtual
DWO file (generally based on the line and abbrev section offsets -
a heuristic that seems to work in practice). */
struct dwo_file
{
dwo_file () = default;
DISABLE_COPY_AND_ASSIGN (dwo_file);
/* The DW_AT_GNU_dwo_name or DW_AT_dwo_name attribute.
For virtual DWO files the name is constructed from the section offsets
of abbrev,line,loc,str_offsets so that we combine virtual DWO files
from related CU+TUs. */
std::string dwo_name;
/* The DW_AT_comp_dir attribute. */
const char *comp_dir = nullptr;
/* The bfd, when the file is open. Otherwise this is NULL.
This is unused(NULL) for virtual DWO files where we use dwp_file.dbfd. */
gdb_bfd_ref_ptr dbfd;
/* The sections that make up this DWO file.
Remember that for virtual DWO files in DWP V2 or DWP V5, these are virtual
sections (for lack of a better name). */
struct dwo_sections sections {};
/* The CUs in the file.
Multiple CUs per DWO are supported as an extension to handle LLVM's Link
Time Optimization output (where multiple source files may be compiled into
a single object/dwo pair). */
dwo_unit_set cus;
/* Table of TUs in the file. */
dwo_unit_set tus;
};
/* See dwarf2/read.h. */
std::size_t
dwo_file_hash::operator() (const dwo_file_search &search) const noexcept
{
hashval_t hash = htab_hash_string (search.dwo_name);
if (search.comp_dir != nullptr)
hash += htab_hash_string (search.comp_dir);
return hash;
}
/* See dwarf2/read.h. */
std::size_t
dwo_file_hash::operator() (const dwo_file_up &file) const noexcept
{
return (*this) ({ file->dwo_name.c_str (), file->comp_dir });
}
/* See dwarf2/read.h. */
bool
dwo_file_eq::operator() (const dwo_file_search &search,
const dwo_file_up &dwo_file) const noexcept
{
if (search.dwo_name != dwo_file->dwo_name)
return false;
if (search.comp_dir == nullptr || dwo_file->comp_dir == nullptr)
return search.comp_dir == dwo_file->comp_dir;
return std::strcmp (search.comp_dir, dwo_file->comp_dir) == 0;
}
/* See dwarf2/read.h. */
bool
dwo_file_eq::operator() (const dwo_file_up &a,
const dwo_file_up &b) const noexcept
{ return (*this) ({ a->dwo_name.c_str (), a->comp_dir }, b); }
/* These sections are what may appear in a DWP file. */
struct dwp_sections
{
/* These are used by all DWP versions (1, 2 and 5). */
struct dwarf2_section_info str;
struct dwarf2_section_info cu_index;
struct dwarf2_section_info tu_index;
/* These are only used by DWP version 2 and version 5 files.
In DWP version 1 the .debug_info.dwo, .debug_types.dwo, and other
sections are referenced by section number, and are not recorded here.
In DWP version 2 or 5 there is at most one copy of all these sections,
each section being (effectively) comprised of the concatenation of all of
the individual sections that exist in the version 1 format.
To keep the code simple we treat each of these concatenated pieces as a
section itself (a virtual section?). */
struct dwarf2_section_info abbrev;
struct dwarf2_section_info info;
struct dwarf2_section_info line;
struct dwarf2_section_info loc;
struct dwarf2_section_info loclists;
struct dwarf2_section_info macinfo;
struct dwarf2_section_info macro;
struct dwarf2_section_info rnglists;
struct dwarf2_section_info str_offsets;
struct dwarf2_section_info types;
};
/* These sections are what may appear in a virtual DWO file in DWP version 1.
A virtual DWO file is a DWO file as it appears in a DWP file. */
struct virtual_v1_dwo_sections
{
struct dwarf2_section_info abbrev;
struct dwarf2_section_info line;
struct dwarf2_section_info loc;
struct dwarf2_section_info macinfo;
struct dwarf2_section_info macro;
struct dwarf2_section_info str_offsets;
/* Each DWP hash table entry records one CU or one TU.
That is recorded here, and copied to dwo_unit.section. */
struct dwarf2_section_info info_or_types;
};
/* Similar to virtual_v1_dwo_sections, but for DWP version 2 or 5.
In version 2, the sections of the DWO files are concatenated together
and stored in one section of that name. Thus each ELF section contains
several "virtual" sections. */
struct virtual_v2_or_v5_dwo_sections
{
bfd_size_type abbrev_offset;
bfd_size_type abbrev_size;
bfd_size_type line_offset;
bfd_size_type line_size;
bfd_size_type loc_offset;
bfd_size_type loc_size;
bfd_size_type loclists_offset;
bfd_size_type loclists_size;
bfd_size_type macinfo_offset;
bfd_size_type macinfo_size;
bfd_size_type macro_offset;
bfd_size_type macro_size;
bfd_size_type rnglists_offset;
bfd_size_type rnglists_size;
bfd_size_type str_offsets_offset;
bfd_size_type str_offsets_size;
/* Each DWP hash table entry records one CU or one TU.
That is recorded here, and copied to dwo_unit.section. */
bfd_size_type info_or_types_offset;
bfd_size_type info_or_types_size;
};
/* Contents of DWP hash tables. */
struct dwp_hash_table
{
uint32_t version, nr_columns;
uint32_t nr_units, nr_slots;
const gdb_byte *hash_table, *unit_table;
union
{
struct
{
const gdb_byte *indices;
} v1;
struct
{
/* This is indexed by column number and gives the id of the section
in that column. */
#define MAX_NR_V2_DWO_SECTIONS \
(1 /* .debug_info or .debug_types */ \
+ 1 /* .debug_abbrev */ \
+ 1 /* .debug_line */ \
+ 1 /* .debug_loc */ \
+ 1 /* .debug_str_offsets */ \
+ 1 /* .debug_macro or .debug_macinfo */)
int section_ids[MAX_NR_V2_DWO_SECTIONS];
const gdb_byte *offsets;
const gdb_byte *sizes;
} v2;
struct
{
/* This is indexed by column number and gives the id of the section
in that column. */
#define MAX_NR_V5_DWO_SECTIONS \
(1 /* .debug_info */ \
+ 1 /* .debug_abbrev */ \
+ 1 /* .debug_line */ \
+ 1 /* .debug_loclists */ \
+ 1 /* .debug_str_offsets */ \
+ 1 /* .debug_macro */ \
+ 1 /* .debug_rnglists */)
int section_ids[MAX_NR_V5_DWO_SECTIONS];
const gdb_byte *offsets;
const gdb_byte *sizes;
} v5;
} section_pool;
};
/* Data for one DWP file. */
struct dwp_file
{
dwp_file (const char *name_, gdb_bfd_ref_ptr &&abfd)
: name (name_),
dbfd (std::move (abfd))
{
}
/* Name of the file. */
const char *name;
/* File format version. */
int version = 0;
/* The bfd. */
gdb_bfd_ref_ptr dbfd;
/* Section info for this file. */
struct dwp_sections sections {};
/* Table of CUs in the file. */
const struct dwp_hash_table *cus = nullptr;
/* Table of TUs in the file. */
const struct dwp_hash_table *tus = nullptr;
/* Tables of loaded CUs/TUs. */
dwo_unit_set loaded_cus;
dwo_unit_set loaded_tus;
/* Table to map ELF section numbers to their sections.
This is only needed for the DWP V1 file format. */
unsigned int num_sections = 0;
asection **elf_sections = nullptr;
};
/* FIXME: We might want to set this from BFD via bfd_arch_bits_per_byte,
but this would require a corresponding change in unpack_field_as_long
and friends. */
static int bits_per_byte = 8;
struct variant_part_builder;
/* When reading a variant, we track a bit more information about the
field, and store it in an object of this type. */
struct variant_field
{
int first_field = -1;
int last_field = -1;
/* A variant can contain other variant parts. */
std::vector<variant_part_builder> variant_parts;
/* If we see a DW_TAG_variant, then this will be set if this is the
default branch. */
bool default_branch = false;
/* If we see a DW_AT_discr_value, then this will be the discriminant
value. */
ULONGEST discriminant_value = 0;
/* If we see a DW_AT_discr_list, then this is a pointer to the list
data. */
struct dwarf_block *discr_list_data = nullptr;
};
/* This represents a DW_TAG_variant_part. */
struct variant_part_builder
{
/* The offset of the discriminant field. */
sect_offset discriminant_offset {};
/* Variants that are direct children of this variant part. */
std::vector<variant_field> variants;
/* True if we're currently reading a variant. */
bool processing_variant = false;
};
struct nextfield
{
/* Variant parts need to find the discriminant, which is a DIE
reference. We track the section offset of each field to make
this link. */
sect_offset offset;
struct field field {};
};
struct fnfieldlist
{
const char *name = nullptr;
std::vector<struct fn_field> fnfields;
};
/* The routines that read and process dies for a C struct or C++ class
pass lists of data member fields and lists of member function fields
in an instance of a field_info structure, as defined below. */
struct field_info
{
/* List of data member and baseclasses fields. */
std::vector<struct nextfield> fields;
std::vector<struct nextfield> baseclasses;
/* Member function fieldlist array, contains name of possibly overloaded
member function, number of overloaded member functions and a pointer
to the head of the member function field chain. */
std::vector<struct fnfieldlist> fnfieldlists;
/* typedefs defined inside this class. TYPEDEF_FIELD_LIST contains head of
a NULL terminated list of TYPEDEF_FIELD_LIST_COUNT elements. */
std::vector<struct decl_field> typedef_field_list;
/* Nested types defined by this class and the number of elements in this
list. */
std::vector<struct decl_field> nested_types_list;
/* If non-null, this is the variant part we are currently
reading. */
variant_part_builder *current_variant_part = nullptr;
/* This holds all the top-level variant parts attached to the type
we're reading. */
std::vector<variant_part_builder> variant_parts;
/* Return the total number of fields (including baseclasses). */
int nfields () const
{
return fields.size () + baseclasses.size ();
}
};
/* Loaded secondary compilation units are kept in memory until they
have not been referenced for the processing of this many
compilation units. Set this to zero to disable caching. Cache
sizes of up to at least twenty will improve startup time for
typical inter-CU-reference binaries, at an obvious memory cost. */
static int dwarf_max_cache_age = 5;
static void
show_dwarf_max_cache_age (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
gdb_printf (file, _("The upper bound on the age of cached "
"DWARF compilation units is %s.\n"),
value);
}
/* When true, wait for DWARF reading to be complete. */
static bool dwarf_synchronous = false;
/* "Show" callback for "maint set dwarf synchronous". */
static void
show_dwarf_synchronous (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
gdb_printf (file, _("Whether DWARF reading is synchronous is %s.\n"),
value);
}
/* local function prototypes */
static void build_type_psymtabs_reader (cutu_reader *reader,
cooked_index_storage *storage);
static void var_decode_location (struct attribute *attr,
struct symbol *sym,
struct dwarf2_cu *cu);
static unsigned int peek_abbrev_code (bfd *, const gdb_byte *);
static unrelocated_addr read_addr_index (struct dwarf2_cu *cu,
unsigned int addr_index);
static sect_offset read_abbrev_offset (dwarf2_per_objfile *per_objfile,
dwarf2_section_info *, sect_offset);
static const char *read_indirect_string
(dwarf2_per_objfile *per_objfile, bfd *, const gdb_byte *,
const struct comp_unit_head *, unsigned int *);
static unrelocated_addr read_addr_index_from_leb128 (struct dwarf2_cu *,
const gdb_byte *,
unsigned int *);
static const char *read_stub_str_index (struct dwarf2_cu *cu,
ULONGEST str_index);
static struct attribute *dwarf2_attr (struct die_info *, unsigned int,
struct dwarf2_cu *);
static const char *dwarf2_string_attr (struct die_info *die, unsigned int name,
struct dwarf2_cu *cu);
static const char *dwarf2_dwo_name (struct die_info *die, struct dwarf2_cu *cu);
static int dwarf2_flag_true_p (struct die_info *die, unsigned name,
struct dwarf2_cu *cu);
static int die_is_declaration (struct die_info *, struct dwarf2_cu *cu);
static struct die_info *die_specification (struct die_info *die,
struct dwarf2_cu **);
static line_header_up dwarf_decode_line_header (sect_offset sect_off,
struct dwarf2_cu *cu,
const char *comp_dir);
static void dwarf_decode_lines (struct line_header *,
struct dwarf2_cu *,
unrelocated_addr, int decode_mapping);
static void dwarf2_start_subfile (dwarf2_cu *cu, const file_entry &fe,
const line_header &lh);
static struct symbol *new_symbol (struct die_info *, struct type *,
struct dwarf2_cu *, struct symbol * = NULL);
static void dwarf2_const_value (const struct attribute *, struct symbol *,
struct dwarf2_cu *);
static void dwarf2_const_value_attr (const struct attribute *attr,
struct type *type,
const char *name,
struct obstack *obstack,
struct dwarf2_cu *cu, LONGEST *value,
const gdb_byte **bytes,
struct dwarf2_locexpr_baton **baton);
static struct type *read_subrange_index_type (struct die_info *die,
struct dwarf2_cu *cu);
static struct type *die_type (struct die_info *, struct dwarf2_cu *);
static int need_gnat_info (struct dwarf2_cu *);
static struct type *die_descriptive_type (struct die_info *,
struct dwarf2_cu *);
static void set_descriptive_type (struct type *, struct die_info *,
struct dwarf2_cu *);
static struct type *die_containing_type (struct die_info *,
struct dwarf2_cu *);
static struct type *lookup_die_type (struct die_info *, const struct attribute *,
struct dwarf2_cu *);
static struct type *read_type_die (struct die_info *, struct dwarf2_cu *);
static struct type *read_type_die_1 (struct die_info *, struct dwarf2_cu *);
static const char *determine_prefix (struct die_info *die, struct dwarf2_cu *);
static gdb::unique_xmalloc_ptr<char> typename_concat (const char *prefix,
const char *suffix,
int physname,
struct dwarf2_cu *cu);
static void read_file_scope (struct die_info *, struct dwarf2_cu *);
static void read_type_unit_scope (struct die_info *, struct dwarf2_cu *);
static void read_func_scope (struct die_info *, struct dwarf2_cu *);
static void read_lexical_block_scope (struct die_info *, struct dwarf2_cu *);
static void read_call_site_scope (struct die_info *die, struct dwarf2_cu *cu);
static void read_variable (struct die_info *die, struct dwarf2_cu *cu);
/* Return the .debug_loclists section to use for cu. */
static struct dwarf2_section_info *cu_debug_loc_section (struct dwarf2_cu *cu);
/* Return the .debug_rnglists section to use for cu. */
static struct dwarf2_section_info *cu_debug_rnglists_section
(struct dwarf2_cu *cu, dwarf_tag tag);
static void get_scope_pc_bounds (struct die_info *,
unrelocated_addr *, unrelocated_addr *,
struct dwarf2_cu *);
static void dwarf2_record_block_ranges (struct die_info *, struct block *,
struct dwarf2_cu *);
static void dwarf2_add_field (struct field_info *, struct die_info *,
struct dwarf2_cu *);
static void dwarf2_attach_fields_to_type (struct field_info *,
struct type *, struct dwarf2_cu *);
static void dwarf2_add_member_fn (struct field_info *,
struct die_info *, struct type *,
struct dwarf2_cu *);
static void dwarf2_attach_fn_fields_to_type (struct field_info *,
struct type *,
struct dwarf2_cu *);
static void process_structure_scope (struct die_info *, struct dwarf2_cu *);
static void read_common_block (struct die_info *, struct dwarf2_cu *);
static void read_namespace (struct die_info *die, struct dwarf2_cu *);
static void read_module (struct die_info *die, struct dwarf2_cu *cu);
static struct using_direct **using_directives (struct dwarf2_cu *cu);
static void read_import_statement (struct die_info *die, struct dwarf2_cu *);
static bool read_alias (struct die_info *die, struct dwarf2_cu *cu);
static struct type *read_module_type (struct die_info *die,
struct dwarf2_cu *cu);
static const char *namespace_name (struct die_info *die,
int *is_anonymous, struct dwarf2_cu *);
static void process_enumeration_scope (struct die_info *, struct dwarf2_cu *);
static enum dwarf_array_dim_ordering read_array_order (struct die_info *,
struct dwarf2_cu *);
static void process_die (struct die_info *, struct dwarf2_cu *);
static const char *dwarf2_canonicalize_name (const char *, struct dwarf2_cu *,
struct objfile *);
static const char *dwarf2_name (struct die_info *die, struct dwarf2_cu *);
static const char *dwarf2_full_name (const char *name,
struct die_info *die,
struct dwarf2_cu *cu);
static const char *dwarf2_physname (const char *name, struct die_info *die,
struct dwarf2_cu *cu);
static struct die_info *dwarf2_extension (struct die_info *die,
struct dwarf2_cu **);
static struct die_info *follow_die_ref_or_sig (struct die_info *,
const struct attribute *,
struct dwarf2_cu **);
static struct die_info *follow_die_ref (struct die_info *,
const struct attribute *,
struct dwarf2_cu **);
static struct die_info *follow_die_sig (struct die_info *,
const struct attribute *,
struct dwarf2_cu **);
static struct type *get_signatured_type (struct die_info *, ULONGEST,
struct dwarf2_cu *);
static struct type *get_DW_AT_signature_type (struct die_info *,
const struct attribute *,
struct dwarf2_cu *);
static void load_full_type_unit (dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile);
static void read_signatured_type (signatured_type *sig_type,
dwarf2_per_objfile *per_objfile);
static int attr_to_dynamic_prop (const struct attribute *attr,
struct die_info *die, struct dwarf2_cu *cu,
struct dynamic_prop *prop, struct type *type);
/* memory allocation interface */
static struct dwarf_block *dwarf_alloc_block (struct dwarf2_cu *);
static void dwarf_decode_macros (struct dwarf2_cu *, unsigned int, int);
static void fill_in_loclist_baton (struct dwarf2_cu *cu,
struct dwarf2_loclist_baton *baton,
const struct attribute *attr);
static void dwarf2_symbol_mark_computed (const struct attribute *attr,
struct symbol *sym,
struct dwarf2_cu *cu,
int is_block);
static struct type *set_die_type (struct die_info *, struct type *,
struct dwarf2_cu *, bool = false);
static void load_full_comp_unit (dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile,
bool skip_partial,
enum language pretend_language);
static void process_full_comp_unit (dwarf2_cu *cu);
static void process_full_type_unit (dwarf2_cu *cu);
static struct type *get_die_type_at_offset (sect_offset,
dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile);
static struct type *get_die_type (struct die_info *die, struct dwarf2_cu *cu);
static void queue_comp_unit (dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile);
static void process_queue (dwarf2_per_objfile *per_objfile);
static bool is_ada_import_or_export (dwarf2_cu *cu, const char *name,
const char *linkagename);
/* Class, the destructor of which frees all allocated queue entries. This
will only have work to do if an error was thrown while processing the
dwarf. If no error was thrown then the queue entries should have all
been processed, and freed, as we went along. */
class dwarf2_queue_guard
{
public:
explicit dwarf2_queue_guard (dwarf2_per_objfile *per_objfile)
: m_per_objfile (per_objfile)
{
gdb_assert (!m_per_objfile->queue.has_value ());
m_per_objfile->queue.emplace ();
}
/* Free any entries remaining on the queue. There should only be
entries left if we hit an error while processing the dwarf. */
~dwarf2_queue_guard ()
{
gdb_assert (m_per_objfile->queue.has_value ());
m_per_objfile->queue.reset ();
}
DISABLE_COPY_AND_ASSIGN (dwarf2_queue_guard);
private:
dwarf2_per_objfile *m_per_objfile;
};
dwarf2_queue_item::~dwarf2_queue_item ()
{
/* Anything still marked queued is likely to be in an
inconsistent state, so discard it. */
if (per_cu->queued)
{
per_objfile->remove_cu (per_cu);
per_cu->queued = 0;
}
}
/* See dwarf2/read.h. */
void
dwarf2_per_cu_deleter::operator() (dwarf2_per_cu *data)
{
if (data->is_debug_types)
delete static_cast<signatured_type *> (data);
else
delete data;
}
static const char *compute_include_file_name
(const struct line_header *lh,
const file_entry &fe,
const file_and_directory &cu_info,
std::string &name_holder);
static struct dwo_unit *lookup_dwo_unit_in_dwp
(dwarf2_per_bfd *per_bfd, struct dwp_file *dwp_file,
const char *comp_dir, ULONGEST signature, int is_debug_types);
static struct dwp_file *get_dwp_file (dwarf2_per_objfile *per_objfile);
static struct dwo_unit *lookup_dwo_comp_unit
(dwarf2_cu *cu, const char *dwo_name, const char *comp_dir,
ULONGEST signature);
static struct dwo_unit *lookup_dwo_type_unit
(dwarf2_cu *cu, const char *dwo_name, const char *comp_dir);
static void queue_and_load_all_dwo_tus (dwarf2_cu *cu);
static void process_cu_includes (dwarf2_per_objfile *per_objfile);
/* Various complaints about symbol reading that don't abort the process. */
static void
dwarf2_debug_line_missing_file_complaint (void)
{
complaint (_(".debug_line section has line data without a file"));
}
static void
dwarf2_debug_line_missing_end_sequence_complaint (void)
{
complaint (_(".debug_line section has line "
"program sequence without an end"));
}
static void
dwarf2_complex_location_expr_complaint (void)
{
complaint (_("location expression too complex"));
}
static void
dwarf2_const_value_length_mismatch_complaint (const char *arg1, int arg2,
int arg3)
{
complaint (_("const value length mismatch for '%s', got %d, expected %d"),
arg1, arg2, arg3);
}
static void
dwarf2_invalid_attrib_class_complaint (const char *arg1, const char *arg2)
{
complaint (_("invalid attribute class or form for '%s' in '%s'"),
arg1, arg2);
}
/* See read.h. */
CORE_ADDR
dwarf2_per_objfile::relocate (unrelocated_addr addr)
{
CORE_ADDR baseaddr = objfile->text_section_offset ();
CORE_ADDR tem = (CORE_ADDR) addr + baseaddr;
return gdbarch_adjust_dwarf2_addr (objfile->arch (), tem);
}
/* Hash function for line_header_hash. */
static hashval_t
line_header_hash (const struct line_header *ofs)
{
return to_underlying (ofs->sect_off) ^ ofs->offset_in_dwz;
}
/* Hash function for htab_create_alloc_ex for line_header_hash. */
static hashval_t
line_header_hash_voidp (const void *item)
{
const struct line_header *ofs = (const struct line_header *) item;
return line_header_hash (ofs);
}
/* Equality function for line_header_hash. */
static int
line_header_eq_voidp (const void *item_lhs, const void *item_rhs)
{
const struct line_header *ofs_lhs = (const struct line_header *) item_lhs;
const struct line_header *ofs_rhs = (const struct line_header *) item_rhs;
return (ofs_lhs->sect_off == ofs_rhs->sect_off
&& ofs_lhs->offset_in_dwz == ofs_rhs->offset_in_dwz);
}
/* See declaration. */
dwarf2_per_bfd::dwarf2_per_bfd (bfd *obfd, const dwarf2_debug_sections *names,
bool can_copy_)
: obfd (obfd),
can_copy (can_copy_),
captured_cwd (current_directory),
captured_debug_dir (debug_file_directory)
{
if (names == NULL)
names = &dwarf2_elf_names;
for (asection *sec = obfd->sections; sec != NULL; sec = sec->next)
this->locate_sections (sec, *names);
}
dwarf2_per_bfd::~dwarf2_per_bfd ()
{
/* Data from the per-BFD may be needed when finalizing the cooked
index table, so wait here while this happens. */
if (index_table != nullptr)
index_table->wait_completely ();
for (auto &per_cu : all_units)
per_cu->free_cached_file_names ();
/* Everything else should be on this->obstack. */
}
/* See read.h. */
void
dwarf2_per_objfile::remove_all_cus ()
{
gdb_assert (!queue.has_value ());
m_dwarf2_cus.clear ();
}
/* A helper class that calls free_cached_comp_units on
destruction. */
class free_cached_comp_units
{
public:
explicit free_cached_comp_units (dwarf2_per_objfile *per_objfile)
: m_per_objfile (per_objfile)
{
}
~free_cached_comp_units ()
{
m_per_objfile->remove_all_cus ();
}
DISABLE_COPY_AND_ASSIGN (free_cached_comp_units);
private:
dwarf2_per_objfile *m_per_objfile;
};
/* See read.h. */
bool
dwarf2_per_objfile::symtab_set_p (const dwarf2_per_cu *per_cu) const
{
if (per_cu->index < m_symtabs.size ())
return m_symtabs[per_cu->index] != nullptr;
return false;
}
/* See read.h. */
compunit_symtab *
dwarf2_per_objfile::get_symtab (const dwarf2_per_cu *per_cu) const
{
if (per_cu->index < m_symtabs.size ())
return m_symtabs[per_cu->index];
return nullptr;
}
/* See read.h. */
void
dwarf2_per_objfile::set_symtab (const dwarf2_per_cu *per_cu,
compunit_symtab *symtab)
{
if (per_cu->index >= m_symtabs.size ())
m_symtabs.resize (per_cu->index + 1);
gdb_assert (m_symtabs[per_cu->index] == nullptr);
m_symtabs[per_cu->index] = symtab;
}
/* Helper function for dwarf2_initialize_objfile that creates the
per-BFD object. */
static bool
dwarf2_has_info (struct objfile *objfile,
const struct dwarf2_debug_sections *names,
bool can_copy)
{
if (objfile->flags & OBJF_READNEVER)
return false;
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
bool just_created = false;
if (per_objfile == NULL)
{
dwarf2_per_bfd *per_bfd;
/* We can share a "dwarf2_per_bfd" with other objfiles if the
BFD doesn't require relocations.
We don't share with objfiles for which -readnow was requested,
because it would complicate things when loading the same BFD with
-readnow and then without -readnow. */
if (!gdb_bfd_requires_relocations (objfile->obfd.get ())
&& (objfile->flags & OBJF_READNOW) == 0)
{
/* See if one has been created for this BFD yet. */
per_bfd = dwarf2_per_bfd_bfd_data_key.get (objfile->obfd.get ());
if (per_bfd == nullptr)
{
/* No, create it now. */
per_bfd = new dwarf2_per_bfd (objfile->obfd.get (), names,
can_copy);
dwarf2_per_bfd_bfd_data_key.set (objfile->obfd.get (), per_bfd);
just_created = true;
}
}
else
{
/* No sharing possible, create one specifically for this objfile. */
per_bfd = new dwarf2_per_bfd (objfile->obfd.get (), names, can_copy);
dwarf2_per_bfd_objfile_data_key.set (objfile, per_bfd);
just_created = true;
}
per_objfile = dwarf2_objfile_data_key.emplace (objfile, objfile, per_bfd);
}
/* Virtual sections are created from DWP files. It's not clear those
can occur here, so perhaps the is_virtual checks here are dead code. */
const bool has_info = (!per_objfile->per_bfd->infos.empty ()
&& !per_objfile->per_bfd->infos[0].is_virtual
&& per_objfile->per_bfd->infos[0].s.section != nullptr
&& !per_objfile->per_bfd->abbrev.is_virtual
&& per_objfile->per_bfd->abbrev.s.section != nullptr);
if (just_created && has_info)
{
/* Try to fetch any potential dwz file early, while still on
the main thread. Also, be sure to do it just once per
BFD, to avoid races. */
try
{
dwarf2_read_dwz_file (per_objfile);
}
catch (const gdb_exception_error &err)
{
warning (_("%s"), err.what ());
}
}
return has_info;
}
/* See declaration. */
void
dwarf2_per_bfd::locate_sections (asection *sectp,
const dwarf2_debug_sections &names)
{
flagword aflag = bfd_section_flags (sectp);
if ((aflag & SEC_HAS_CONTENTS) == 0)
{
}
else if (bfd_section_size_insane (this->obfd, sectp))
{
bfd_size_type size = sectp->size;
warning (_("Discarding section %s which has an invalid size (%s) "
"[in module %s]"),
bfd_section_name (sectp), phex_nz (size, sizeof (size)),
this->filename ());
}
else if (names.info.matches (sectp->name))
{
struct dwarf2_section_info info_section;
memset (&info_section, 0, sizeof (info_section));
info_section.s.section = sectp;
info_section.size = bfd_section_size (sectp);
this->infos.push_back (info_section);
}
else if (names.abbrev.matches (sectp->name))
{
this->abbrev.s.section = sectp;
this->abbrev.size = bfd_section_size (sectp);
}
else if (names.line.matches (sectp->name))
{
this->line.s.section = sectp;
this->line.size = bfd_section_size (sectp);
}
else if (names.loc.matches (sectp->name))
{
this->loc.s.section = sectp;
this->loc.size = bfd_section_size (sectp);
}
else if (names.loclists.matches (sectp->name))
{
this->loclists.s.section = sectp;
this->loclists.size = bfd_section_size (sectp);
}
else if (names.macinfo.matches (sectp->name))
{
this->macinfo.s.section = sectp;
this->macinfo.size = bfd_section_size (sectp);
}
else if (names.macro.matches (sectp->name))
{
this->macro.s.section = sectp;
this->macro.size = bfd_section_size (sectp);
}
else if (names.str.matches (sectp->name))
{
this->str.s.section = sectp;
this->str.size = bfd_section_size (sectp);
}
else if (names.str_offsets.matches (sectp->name))
{
this->str_offsets.s.section = sectp;
this->str_offsets.size = bfd_section_size (sectp);
}
else if (names.line_str.matches (sectp->name))
{
this->line_str.s.section = sectp;
this->line_str.size = bfd_section_size (sectp);
}
else if (names.addr.matches (sectp->name))
{
this->addr.s.section = sectp;
this->addr.size = bfd_section_size (sectp);
}
else if (names.frame.matches (sectp->name))
{
this->frame.s.section = sectp;
this->frame.size = bfd_section_size (sectp);
}
else if (names.eh_frame.matches (sectp->name))
{
this->eh_frame.s.section = sectp;
this->eh_frame.size = bfd_section_size (sectp);
}
else if (names.ranges.matches (sectp->name))
{
this->ranges.s.section = sectp;
this->ranges.size = bfd_section_size (sectp);
}
else if (names.rnglists.matches (sectp->name))
{
this->rnglists.s.section = sectp;
this->rnglists.size = bfd_section_size (sectp);
}
else if (names.types.matches (sectp->name))
{
struct dwarf2_section_info type_section;
memset (&type_section, 0, sizeof (type_section));
type_section.s.section = sectp;
type_section.size = bfd_section_size (sectp);
this->types.push_back (type_section);
}
else if (names.gdb_index.matches (sectp->name))
{
this->gdb_index.s.section = sectp;
this->gdb_index.size = bfd_section_size (sectp);
}
else if (names.debug_names.matches (sectp->name))
{
this->debug_names.s.section = sectp;
this->debug_names.size = bfd_section_size (sectp);
}
else if (names.debug_aranges.matches (sectp->name))
{
this->debug_aranges.s.section = sectp;
this->debug_aranges.size = bfd_section_size (sectp);
}
if ((bfd_section_flags (sectp) & (SEC_LOAD | SEC_ALLOC))
&& bfd_section_vma (sectp) == 0)
this->has_section_at_zero = true;
}
/* Fill in SECTP, BUFP and SIZEP with section info, given OBJFILE and
SECTION_NAME. */
void
dwarf2_get_section_info (struct objfile *objfile,
enum dwarf2_section_enum sect,
asection **sectp, const gdb_byte **bufp,
bfd_size_type *sizep)
{
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
struct dwarf2_section_info *info;
/* We may see an objfile without any DWARF, in which case we just
return nothing. */
if (per_objfile == NULL)
{
*sectp = NULL;
*bufp = NULL;
*sizep = 0;
return;
}
switch (sect)
{
case DWARF2_DEBUG_FRAME:
info = &per_objfile->per_bfd->frame;
break;
case DWARF2_EH_FRAME:
info = &per_objfile->per_bfd->eh_frame;
break;
default:
gdb_assert_not_reached ("unexpected section");
}
info->read (objfile);
*sectp = info->get_bfd_section ();
*bufp = info->buffer;
*sizep = info->size;
}
/* See dwarf2/read.h. */
void
dwarf2_per_bfd::map_info_sections (struct objfile *objfile)
{
for (auto &section : infos)
section.read (objfile);
abbrev.read (objfile);
line.read (objfile);
str.read (objfile);
str_offsets.read (objfile);
line_str.read (objfile);
ranges.read (objfile);
rnglists.read (objfile);
addr.read (objfile);
debug_aranges.read (objfile);
for (auto &section : types)
section.read (objfile);
}
/* See dwarf2/read.h. */
void
dwarf2_per_bfd::start_reading (dwarf_scanner_base_up new_table)
{
gdb_assert (index_table == nullptr);
index_table = std::move (new_table);
index_table->start_reading ();
}
/* DWARF quick_symbol_functions support. */
/* TUs can share .debug_line entries, and there can be a lot more TUs than
unique line tables, so we maintain a separate table of all .debug_line
derived entries to support the sharing.
All the quick functions need is the list of file names. We discard the
line_header when we're done and don't need to record it here. */
struct quick_file_names
{
/* The number of entries in file_names, real_names. */
unsigned int num_file_names;
/* The CU directory, as given by DW_AT_comp_dir. May be
nullptr. */
const char *comp_dir;
/* The file names from the line table, after being run through
file_full_name. */
const char **file_names;
/* The file names from the line table after being run through
gdb_realpath. These are computed lazily. */
const char **real_names;
};
/* With OBJF_READNOW, the DWARF reader expands all CUs immediately.
It's handy in this case to have an empty implementation of the
quick symbol functions, to avoid special cases in the rest of the
code. */
struct readnow_functions : public dwarf2_base_index_functions
{
void dump (struct objfile *objfile) override
{
}
bool expand_symtabs_matching
(struct objfile *objfile,
expand_symtabs_file_matcher file_matcher,
const lookup_name_info *lookup_name,
expand_symtabs_symbol_matcher symbol_matcher,
expand_symtabs_expansion_listener expansion_notify,
block_search_flags search_flags,
domain_search_flags domain,
expand_symtabs_lang_matcher lang_matcher) override
{
return true;
}
};
/* See read.h. */
std::uint64_t
stmt_list_hash_hash::operator() (const stmt_list_hash &key) const noexcept
{
std::uint64_t v = 0;
if (key.dwo_unit != nullptr)
v += ankerl::unordered_dense::hash<dwo_file *> () (key.dwo_unit->dwo_file);
v += (ankerl::unordered_dense::hash<std::uint64_t> ()
(to_underlying (key.line_sect_off)));
return v;
}
/* See read.h. */
bool
stmt_list_hash::operator== (const stmt_list_hash &rhs) const noexcept
{
if ((this->dwo_unit != nullptr) != (rhs.dwo_unit != nullptr))
return false;
if (this->dwo_unit != nullptr
&& this->dwo_unit->dwo_file != rhs.dwo_unit->dwo_file)
return false;
return this->line_sect_off == rhs.line_sect_off;
}
/* Read in CU (dwarf2_cu object) for PER_CU in the context of PER_OBJFILE. This
function is unrelated to symtabs, symtab would have to be created afterwards.
You should call age_cached_comp_units after processing the CU. */
static dwarf2_cu *
load_cu (dwarf2_per_cu *per_cu, dwarf2_per_objfile *per_objfile,
bool skip_partial)
{
if (per_cu->is_debug_types)
load_full_type_unit (per_cu, per_objfile);
else
load_full_comp_unit (per_cu, per_objfile, skip_partial, language_minimal);
dwarf2_cu *cu = per_objfile->get_cu (per_cu);
if (cu == nullptr)
return nullptr; /* Dummy CU. */
dwarf2_find_base_address (cu->dies, cu);
return cu;
}
/* Read in the symbols for PER_CU in the context of PER_OBJFILE. */
static void
dw2_do_instantiate_symtab (dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile, bool skip_partial)
{
{
/* The destructor of dwarf2_queue_guard frees any entries left on
the queue. After this point we're guaranteed to leave this function
with the dwarf queue empty. */
dwarf2_queue_guard q_guard (per_objfile);
if (!per_objfile->symtab_set_p (per_cu))
{
queue_comp_unit (per_cu, per_objfile);
dwarf2_cu *cu = per_objfile->get_cu (per_cu);
if (cu == nullptr)
cu = load_cu (per_cu, per_objfile, skip_partial);
/* If we just loaded a CU from a DWO, and we're working with an index
that may badly handle TUs, load all the TUs in that DWO as well.
http://sourceware.org/bugzilla/show_bug.cgi?id=15021 */
if (!per_cu->is_debug_types
&& cu != NULL
&& cu->dwo_unit != NULL
&& per_objfile->per_bfd->index_table != NULL
&& !per_objfile->per_bfd->index_table->version_check ()
/* DWP files aren't supported yet. */
&& get_dwp_file (per_objfile) == NULL)
queue_and_load_all_dwo_tus (cu);
}
process_queue (per_objfile);
}
/* Age the cache, releasing compilation units that have not
been used recently. */
per_objfile->age_comp_units ();
}
/* Ensure that the symbols for PER_CU have been read in. DWARF2_PER_OBJFILE is
the per-objfile for which this symtab is instantiated.
Returns the resulting symbol table. */
static struct compunit_symtab *
dw2_instantiate_symtab (dwarf2_per_cu *per_cu, dwarf2_per_objfile *per_objfile,
bool skip_partial)
{
if (!per_objfile->symtab_set_p (per_cu))
{
free_cached_comp_units freer (per_objfile);
scoped_restore decrementer = increment_reading_symtab ();
dw2_do_instantiate_symtab (per_cu, per_objfile, skip_partial);
process_cu_includes (per_objfile);
}
return per_objfile->get_symtab (per_cu);
}
/* See read.h. */
dwarf2_per_cu_up
dwarf2_per_bfd::allocate_per_cu (dwarf2_section_info *section,
sect_offset sect_off, unsigned int length,
bool is_dwz)
{
dwarf2_per_cu_up result (new dwarf2_per_cu (this, section, sect_off,
length, is_dwz));
result->index = all_units.size ();
return result;
}
/* See read.h. */
signatured_type_up
dwarf2_per_bfd::allocate_signatured_type (dwarf2_section_info *section,
sect_offset sect_off,
unsigned int length,
bool is_dwz,
ULONGEST signature)
{
auto result
= std::make_unique<signatured_type> (this, section, sect_off, length,
is_dwz, signature);
result->index = all_units.size ();
tu_stats.nr_tus++;
return result;
}
/* die_reader_func for dw2_get_file_names. */
static void
dw2_get_file_names_reader (dwarf2_cu *cu, die_info *comp_unit_die)
{
dwarf2_per_cu *this_cu = cu->per_cu;
dwarf2_per_objfile *per_objfile = cu->per_objfile;
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
gdb_assert (! this_cu->is_debug_types);
this_cu->files_read = true;
/* Our callers never want to match partial units -- instead they
will match the enclosing full CU. */
if (comp_unit_die->tag == DW_TAG_partial_unit)
return;
line_header_up lh;
file_and_directory &fnd = find_file_and_directory (comp_unit_die, cu);
std::optional<stmt_list_hash> stmt_list_hash_key;
attribute *attr = dwarf2_attr (comp_unit_die, DW_AT_stmt_list, cu);
if (attr != nullptr && attr->form_is_unsigned ())
{
sect_offset line_offset = (sect_offset) attr->as_unsigned ();
/* We may have already read in this line header (TU line header sharing).
If we have we're done. */
stmt_list_hash_key = {cu->dwo_unit, line_offset};
if (auto it = per_bfd->quick_file_names_table.find (*stmt_list_hash_key);
it != per_bfd->quick_file_names_table.end ())
{
this_cu->file_names = it->second;
return;
}
lh = dwarf_decode_line_header (line_offset, cu, fnd.get_comp_dir ());
}
int offset = 0;
if (!fnd.is_unknown ())
++offset;
else if (lh == nullptr)
return;
auto *qfn = XOBNEW (&per_bfd->obstack, quick_file_names);
/* There may not be a DW_AT_stmt_list. */
if (stmt_list_hash_key.has_value ())
per_bfd->quick_file_names_table.emplace (*stmt_list_hash_key, qfn);
std::vector<const char *> include_names;
if (lh != nullptr)
{
for (const auto &entry : lh->file_names ())
{
std::string name_holder;
const char *include_name =
compute_include_file_name (lh.get (), entry, fnd, name_holder);
if (include_name != nullptr)
{
include_name = per_objfile->objfile->intern (include_name);
include_names.push_back (include_name);
}
}
}
qfn->num_file_names = offset + include_names.size ();
qfn->comp_dir = fnd.intern_comp_dir (per_objfile->objfile);
qfn->file_names
= XOBNEWVEC (&per_bfd->obstack, const char *, qfn->num_file_names);
if (offset != 0)
qfn->file_names[0] = per_objfile->objfile->intern (fnd.get_name ());
if (!include_names.empty ())
memcpy (&qfn->file_names[offset], include_names.data (),
include_names.size () * sizeof (const char *));
qfn->real_names = NULL;
this_cu->file_names = qfn;
}
/* A helper for the "quick" functions which attempts to read the line
table for THIS_CU. */
static struct quick_file_names *
dw2_get_file_names (dwarf2_per_cu *this_cu, dwarf2_per_objfile *per_objfile)
{
/* This should never be called for TUs. */
gdb_assert (! this_cu->is_debug_types);
if (this_cu->files_read)
return this_cu->file_names;
cutu_reader reader (this_cu, per_objfile, nullptr,
per_objfile->get_cu (this_cu), true, language_minimal,
nullptr);
if (!reader.is_dummy ())
dw2_get_file_names_reader (reader.cu (), reader.top_level_die ());
return this_cu->file_names;
}
/* A helper for the "quick" functions which computes and caches the
real path for a given file name from the line table. */
static const char *
dw2_get_real_path (dwarf2_per_objfile *per_objfile,
struct quick_file_names *qfn, int index)
{
if (qfn->real_names == NULL)
qfn->real_names = OBSTACK_CALLOC (&per_objfile->per_bfd->obstack,
qfn->num_file_names, const char *);
if (qfn->real_names[index] == NULL)
{
const char *dirname = nullptr;
if (!IS_ABSOLUTE_PATH (qfn->file_names[index]))
dirname = qfn->comp_dir;
gdb::unique_xmalloc_ptr<char> fullname;
fullname = find_source_or_rewrite (qfn->file_names[index], dirname);
qfn->real_names[index] = fullname.release ();
}
return qfn->real_names[index];
}
struct symtab *
dwarf2_base_index_functions::find_last_source_symtab (struct objfile *objfile)
{
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
dwarf2_per_cu *dwarf_cu = per_objfile->per_bfd->all_units.back ().get ();
compunit_symtab *cust = dw2_instantiate_symtab (dwarf_cu, per_objfile, false);
if (cust == NULL)
return NULL;
return cust->primary_filetab ();
}
/* See read.h. */
void
dwarf2_per_cu::free_cached_file_names ()
{
if (fnd != nullptr)
fnd->forget_fullname ();
if (per_bfd == nullptr)
return;
struct quick_file_names *file_data = file_names;
if (file_data != nullptr && file_data->real_names != nullptr)
{
for (int i = 0; i < file_data->num_file_names; ++i)
{
xfree ((void *) file_data->real_names[i]);
file_data->real_names[i] = nullptr;
}
}
}
void
dwarf2_base_index_functions::forget_cached_source_info
(struct objfile *objfile)
{
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
for (auto &per_cu : per_objfile->per_bfd->all_units)
per_cu->free_cached_file_names ();
}
void
dwarf2_base_index_functions::print_stats (struct objfile *objfile,
bool print_bcache)
{
if (print_bcache)
return;
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
int total = per_objfile->per_bfd->all_units.size ();
int count = 0;
for (int i = 0; i < total; ++i)
{
dwarf2_per_cu *per_cu = per_objfile->per_bfd->get_cu (i);
if (!per_objfile->symtab_set_p (per_cu))
++count;
}
gdb_printf (_(" Number of read CUs: %d\n"), total - count);
gdb_printf (_(" Number of unread CUs: %d\n"), count);
}
void
dwarf2_base_index_functions::expand_all_symtabs (struct objfile *objfile)
{
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
for (dwarf2_per_cu *per_cu : all_units_range (per_objfile->per_bfd))
{
/* We don't want to directly expand a partial CU, because if we
read it with the wrong language, then assertion failures can
be triggered later on. See PR symtab/23010. So, tell
dw2_instantiate_symtab to skip partial CUs -- any important
partial CU will be read via DW_TAG_imported_unit anyway. */
dw2_instantiate_symtab (per_cu, per_objfile, true);
}
}
/* See read.h. */
bool
dw2_expand_symtabs_matching_one
(dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile,
expand_symtabs_file_matcher file_matcher,
expand_symtabs_expansion_listener expansion_notify,
expand_symtabs_lang_matcher lang_matcher)
{
if (file_matcher != nullptr && !per_cu->mark)
return true;
if (lang_matcher != nullptr)
{
/* Try to skip CUs with non-matching language. */
per_cu->ensure_lang (per_objfile);
if (!per_cu->maybe_multi_language ()
&& !lang_matcher (per_cu->lang ()))
return true;
}
bool symtab_was_null = !per_objfile->symtab_set_p (per_cu);
compunit_symtab *symtab
= dw2_instantiate_symtab (per_cu, per_objfile, false);
gdb_assert (symtab != nullptr);
if (expansion_notify != NULL && symtab_was_null)
return expansion_notify (symtab);
return true;
}
/* See read.h. */
void
dw_expand_symtabs_matching_file_matcher
(dwarf2_per_objfile *per_objfile, expand_symtabs_file_matcher file_matcher)
{
if (file_matcher == NULL)
return;
gdb::unordered_set<quick_file_names *> visited_found;
gdb::unordered_set<quick_file_names *> visited_not_found;
/* The rule is CUs specify all the files, including those used by
any TU, so there's no need to scan TUs here. */
for (const auto &per_cu : per_objfile->per_bfd->all_units)
{
QUIT;
if (per_cu->is_debug_types)
continue;
per_cu->mark = 0;
/* We only need to look at symtabs not already expanded. */
if (per_objfile->symtab_set_p (per_cu.get ()))
continue;
if (per_cu->fnd != nullptr)
{
file_and_directory *fnd = per_cu->fnd.get ();
if (file_matcher (fnd->get_name (), false))
{
per_cu->mark = 1;
continue;
}
/* Before we invoke realpath, which can get expensive when many
files are involved, do a quick comparison of the basenames. */
if ((basenames_may_differ
|| file_matcher (lbasename (fnd->get_name ()), true))
&& file_matcher (fnd->get_fullname (), false))
{
per_cu->mark = 1;
continue;
}
}
quick_file_names *file_data = dw2_get_file_names (per_cu.get (),
per_objfile);
if (file_data == NULL)
continue;
if (visited_not_found.contains (file_data))
continue;
else if (visited_found.contains (file_data))
{
per_cu->mark = 1;
continue;
}
for (int j = 0; j < file_data->num_file_names; ++j)
{
const char *this_real_name;
if (file_matcher (file_data->file_names[j], false))
{
per_cu->mark = 1;
break;
}
/* Before we invoke realpath, which can get expensive when many
files are involved, do a quick comparison of the basenames. */
if (!basenames_may_differ
&& !file_matcher (lbasename (file_data->file_names[j]),
true))
continue;
this_real_name = dw2_get_real_path (per_objfile, file_data, j);
if (file_matcher (this_real_name, false))
{
per_cu->mark = 1;
break;
}
}
if (per_cu->mark)
visited_found.insert (file_data);
else
visited_not_found.insert (file_data);
}
}
/* A helper for dw2_find_pc_sect_compunit_symtab which finds the most specific
symtab. */
static struct compunit_symtab *
recursively_find_pc_sect_compunit_symtab (struct compunit_symtab *cust,
CORE_ADDR pc)
{
int i;
if (cust->blockvector () != nullptr
&& blockvector_contains_pc (cust->blockvector (), pc))
return cust;
if (cust->includes == NULL)
return NULL;
for (i = 0; cust->includes[i]; ++i)
{
struct compunit_symtab *s = cust->includes[i];
s = recursively_find_pc_sect_compunit_symtab (s, pc);
if (s != NULL)
return s;
}
return NULL;
}
struct compunit_symtab *
dwarf2_base_index_functions::find_pc_sect_compunit_symtab
(struct objfile *objfile,
bound_minimal_symbol msymbol,
CORE_ADDR pc,
struct obj_section *section,
int warn_if_readin)
{
struct compunit_symtab *result;
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
if (per_bfd->index_table == nullptr)
return nullptr;
CORE_ADDR baseaddr = objfile->text_section_offset ();
dwarf2_per_cu *data
= per_bfd->index_table->lookup ((unrelocated_addr) (pc - baseaddr));
if (data == nullptr)
return nullptr;
if (warn_if_readin && per_objfile->symtab_set_p (data))
warning (_("(Internal error: pc %s in read in CU, but not in symtab.)"),
paddress (objfile->arch (), pc));
result = recursively_find_pc_sect_compunit_symtab
(dw2_instantiate_symtab (data, per_objfile, false), pc);
if (warn_if_readin && result == nullptr)
warning (_("(Error: pc %s in address map, but not in symtab.)"),
paddress (objfile->arch (), pc));
return result;
}
void
dwarf2_base_index_functions::map_symbol_filenames (objfile *objfile,
symbol_filename_listener fun,
bool need_fullname)
{
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
/* Use caches to ensure we only call FUN once for each filename. */
filename_seen_cache filenames_cache;
gdb::unordered_set<quick_file_names *> qfn_cache;
/* The rule is CUs specify all the files, including those used by any TU,
so there's no need to scan TUs here. We can ignore file names coming
from already-expanded CUs. It is possible that an expanded CU might
reuse the file names data from a currently unexpanded CU, in this
case we don't want to report the files from the unexpanded CU. */
for (const auto &per_cu : per_objfile->per_bfd->all_units)
{
if (!per_cu->is_debug_types
&& per_objfile->symtab_set_p (per_cu.get ()))
{
if (per_cu->file_names != nullptr)
qfn_cache.insert (per_cu->file_names);
}
}
for (dwarf2_per_cu *per_cu : all_units_range (per_objfile->per_bfd))
{
/* We only need to look at symtabs not already expanded. */
if (per_cu->is_debug_types || per_objfile->symtab_set_p (per_cu))
continue;
if (per_cu->fnd != nullptr)
{
file_and_directory *fnd = per_cu->fnd.get ();
const char *filename = fnd->get_name ();
const char *key = filename;
const char *fullname = nullptr;
if (need_fullname)
{
fullname = fnd->get_fullname ();
key = fullname;
}
if (!filenames_cache.seen (key))
fun (filename, fullname);
}
quick_file_names *file_data = dw2_get_file_names (per_cu, per_objfile);
if (file_data == nullptr
|| qfn_cache.find (file_data) != qfn_cache.end ())
continue;
for (int j = 0; j < file_data->num_file_names; ++j)
{
const char *filename = file_data->file_names[j];
const char *key = filename;
const char *fullname = nullptr;
if (need_fullname)
{
fullname = dw2_get_real_path (per_objfile, file_data, j);
key = fullname;
}
if (!filenames_cache.seen (key))
fun (filename, fullname);
}
}
}
bool
dwarf2_base_index_functions::has_symbols (struct objfile *objfile)
{
return true;
}
/* See quick_symbol_functions::has_unexpanded_symtabs in quick-symbol.h. */
bool
dwarf2_base_index_functions::has_unexpanded_symtabs (struct objfile *objfile)
{
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
for (const auto &per_cu : per_objfile->per_bfd->all_units)
{
/* Is this already expanded? */
if (per_objfile->symtab_set_p (per_cu.get ()))
continue;
/* It has not yet been expanded. */
return true;
}
return false;
}
/* Get the content of the .gdb_index section of OBJ. SECTION_OWNER should point
to either a dwarf2_per_bfd or dwz_file object. */
template <typename T>
static gdb::array_view<const gdb_byte>
get_gdb_index_contents_from_section (objfile *obj, T *section_owner)
{
dwarf2_section_info *section = &section_owner->gdb_index;
if (section->empty ())
return {};
/* Older elfutils strip versions could keep the section in the main
executable while splitting it for the separate debug info file. */
if ((section->get_flags () & SEC_HAS_CONTENTS) == 0)
return {};
section->read (obj);
/* dwarf2_section_info::size is a bfd_size_type, while
gdb::array_view works with size_t. On 32-bit hosts, with
--enable-64-bit-bfd, bfd_size_type is a 64-bit type, while size_t
is 32-bit. So we need an explicit narrowing conversion here.
This is fine, because it's impossible to allocate or mmap an
array/buffer larger than what size_t can represent. */
return gdb::make_array_view (section->buffer, section->size);
}
/* Lookup the index cache for the contents of the index associated to
DWARF2_OBJ. */
static gdb::array_view<const gdb_byte>
get_gdb_index_contents_from_cache (objfile *obj, dwarf2_per_bfd *dwarf2_per_bfd)
{
const bfd_build_id *build_id = build_id_bfd_get (obj->obfd.get ());
if (build_id == nullptr)
return {};
return global_index_cache.lookup_gdb_index (build_id,
&dwarf2_per_bfd->index_cache_res);
}
/* Same as the above, but for DWZ. */
static gdb::array_view<const gdb_byte>
get_gdb_index_contents_from_cache_dwz (objfile *obj, dwz_file *dwz)
{
const bfd_build_id *build_id = build_id_bfd_get (dwz->dwz_bfd.get ());
if (build_id == nullptr)
return {};
return global_index_cache.lookup_gdb_index (build_id, &dwz->index_cache_res);
}
static void start_debug_info_reader (dwarf2_per_objfile *);
/* See dwarf2/public.h. */
bool
dwarf2_initialize_objfile (struct objfile *objfile,
const struct dwarf2_debug_sections *names,
bool can_copy)
{
if (!dwarf2_has_info (objfile, names, can_copy))
return false;
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
dwarf_read_debug_printf ("called");
/* If we're about to read full symbols, don't bother with the
indices. In this case we also don't care if some other debug
format is making psymtabs, because they are all about to be
expanded anyway. */
if ((objfile->flags & OBJF_READNOW))
{
dwarf_read_debug_printf ("readnow requested");
create_all_units (per_objfile);
objfile->qf.emplace_front (new readnow_functions);
}
/* Was a GDB index already read when we processed an objfile sharing
PER_BFD? */
else if (per_bfd->index_table != nullptr)
dwarf_read_debug_printf ("re-using symbols");
else if (dwarf2_read_debug_names (per_objfile))
dwarf_read_debug_printf ("found debug names");
else if (dwarf2_read_gdb_index (per_objfile,
get_gdb_index_contents_from_section<struct dwarf2_per_bfd>,
get_gdb_index_contents_from_section<dwz_file>))
dwarf_read_debug_printf ("found gdb index from file");
/* ... otherwise, try to find the index in the index cache. */
else if (dwarf2_read_gdb_index (per_objfile,
get_gdb_index_contents_from_cache,
get_gdb_index_contents_from_cache_dwz))
{
dwarf_read_debug_printf ("found gdb index from cache");
global_index_cache.hit ();
}
else
{
global_index_cache.miss ();
start_debug_info_reader (per_objfile);
}
if (per_bfd->index_table != nullptr)
{
if (dwarf_synchronous)
per_bfd->index_table->wait_completely ();
objfile->qf.push_front (per_bfd->index_table->make_quick_functions ());
}
return true;
}
/* See read.h. */
void
dwarf2_find_base_address (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr;
cu->base_address.reset ();
attr = dwarf2_attr (die, DW_AT_entry_pc, cu);
if (attr != nullptr)
cu->base_address = attr->as_address ();
else
{
attr = dwarf2_attr (die, DW_AT_low_pc, cu);
if (attr != nullptr)
cu->base_address = attr->as_address ();
}
}
/* Helper function that returns the proper abbrev section for
THIS_CU. */
static struct dwarf2_section_info *
get_abbrev_section_for_cu (dwarf2_per_cu *this_cu)
{
struct dwarf2_section_info *abbrev;
dwarf2_per_bfd *per_bfd = this_cu->per_bfd;
if (this_cu->is_dwz)
abbrev = &per_bfd->get_dwz_file (true)->abbrev;
else
abbrev = &per_bfd->abbrev;
return abbrev;
}
/* Fetch the abbreviation table offset from a comp or type unit header. */
static sect_offset
read_abbrev_offset (dwarf2_per_objfile *per_objfile,
struct dwarf2_section_info *section,
sect_offset sect_off)
{
bfd *abfd = section->get_bfd_owner ();
const gdb_byte *info_ptr;
unsigned int initial_length_size, offset_size;
uint16_t version;
section->read (per_objfile->objfile);
info_ptr = section->buffer + to_underlying (sect_off);
read_initial_length (abfd, info_ptr, &initial_length_size);
offset_size = initial_length_size == 4 ? 4 : 8;
info_ptr += initial_length_size;
version = read_2_bytes (abfd, info_ptr);
info_ptr += 2;
if (version >= 5)
{
/* Skip unit type and address size. */
info_ptr += 2;
}
return (sect_offset) read_offset (abfd, info_ptr, offset_size);
}
/* A helper for create_debug_types_hash_table. Read types from SECTION
and fill them into DWO_FILE's type unit hash table. It will process only
type units, therefore DW_UT_type. */
static void
create_debug_type_hash_table (dwarf2_per_objfile *per_objfile,
dwo_file *dwo_file, dwarf2_section_info *section,
rcuh_kind section_kind)
{
struct objfile *objfile = per_objfile->objfile;
struct dwarf2_section_info *abbrev_section;
bfd *abfd;
const gdb_byte *info_ptr, *end_ptr;
abbrev_section = &dwo_file->sections.abbrev;
dwarf_read_debug_printf ("Reading %s for %s",
section->get_name (),
abbrev_section->get_file_name ());
section->read (objfile);
info_ptr = section->buffer;
if (info_ptr == NULL)
return;
/* We can't set abfd until now because the section may be empty or
not present, in which case the bfd is unknown. */
abfd = section->get_bfd_owner ();
/* We don't use cutu_reader here because we don't need to read
any dies: the signature is in the header. */
end_ptr = info_ptr + section->size;
while (info_ptr < end_ptr)
{
const gdb_byte *ptr = info_ptr;
struct comp_unit_head header;
unsigned int length;
sect_offset sect_off = (sect_offset) (ptr - section->buffer);
/* Initialize it due to a false compiler warning. */
header.signature = -1;
header.type_cu_offset_in_tu = (cu_offset) -1;
/* We need to read the type's signature in order to build the hash
table, but we don't need anything else just yet. */
ptr = read_and_check_comp_unit_head (per_objfile, &header, section,
abbrev_section, ptr, section_kind);
length = header.get_length_with_initial ();
/* Skip dummy type units. */
if (ptr >= info_ptr + length
|| peek_abbrev_code (abfd, ptr) == 0
|| (header.unit_type != DW_UT_type
&& header.unit_type != DW_UT_split_type))
{
info_ptr += length;
continue;
}
dwo_unit *dwo_tu
= OBSTACK_ZALLOC (&per_objfile->per_bfd->obstack, dwo_unit);
dwo_tu->dwo_file = dwo_file;
dwo_tu->signature = header.signature;
dwo_tu->type_offset_in_tu = header.type_cu_offset_in_tu;
dwo_tu->section = section;
dwo_tu->sect_off = sect_off;
dwo_tu->length = length;
auto [it, inserted] = dwo_file->tus.emplace (dwo_tu);
if (!inserted)
complaint (_("debug type entry at offset %s is duplicate to"
" the entry at offset %s, signature %s"),
sect_offset_str (sect_off),
sect_offset_str ((*it)->sect_off),
hex_string (header.signature));
dwarf_read_debug_printf_v (" offset %s, signature %s",
sect_offset_str (sect_off),
hex_string (header.signature));
info_ptr += length;
}
}
/* Create the hash table of all entries in the .debug_types
(or .debug_types.dwo) section(s).
DWO_FILE is a pointer to the DWO file object.
Note: This function processes DWO files only, not DWP files. */
static void
create_debug_types_hash_table
(dwarf2_per_objfile *per_objfile, dwo_file *dwo_file,
gdb::array_view<dwarf2_section_info> type_sections)
{
for (dwarf2_section_info &section : type_sections)
create_debug_type_hash_table (per_objfile, dwo_file, &section,
rcuh_kind::TYPE);
}
/* Add an entry for signature SIG to per_bfd->signatured_types. */
static signatured_type_set::iterator
add_type_unit (dwarf2_per_bfd *per_bfd, dwarf2_section_info *section,
sect_offset sect_off, unsigned int length, ULONGEST sig)
{
if (per_bfd->all_units.size () == per_bfd->all_units.capacity ())
++per_bfd->tu_stats.nr_all_type_units_reallocs;
signatured_type_up sig_type_holder
= per_bfd->allocate_signatured_type (section, sect_off, length,
false /* is_dwz */, sig);
signatured_type *sig_type = sig_type_holder.get ();
per_bfd->all_units.emplace_back (sig_type_holder.release ());
auto emplace_ret = per_bfd->signatured_types.emplace (sig_type);
/* Assert that an insertion took place - that there wasn't a type unit with
that signature already. */
gdb_assert (emplace_ret.second);
/* The rest of sig_type must be filled in by the caller. */
return emplace_ret.first;
}
/* Subroutine of lookup_dwo_signatured_type and lookup_dwp_signatured_type.
Fill in SIG_ENTRY with DWO_ENTRY. */
static void
fill_in_sig_entry_from_dwo_entry (dwarf2_per_objfile *per_objfile,
struct signatured_type *sig_entry,
struct dwo_unit *dwo_entry)
{
/* Make sure we're not clobbering something we don't expect to. */
gdb_assert (! sig_entry->queued);
gdb_assert (per_objfile->get_cu (sig_entry) == NULL);
gdb_assert (!per_objfile->symtab_set_p (sig_entry));
gdb_assert (sig_entry->signature == dwo_entry->signature);
gdb_assert (to_underlying (sig_entry->type_offset_in_section) == 0
|| (to_underlying (sig_entry->type_offset_in_section)
== to_underlying (dwo_entry->type_offset_in_tu)));
gdb_assert (!sig_entry->type_unit_group_key.has_value ());
gdb_assert (sig_entry->dwo_unit == NULL
|| sig_entry->dwo_unit == dwo_entry);
sig_entry->reading_dwo_directly = 1;
sig_entry->type_offset_in_tu = dwo_entry->type_offset_in_tu;
sig_entry->dwo_unit = dwo_entry;
}
/* Subroutine of lookup_signatured_type.
If we haven't read the TU yet, create the signatured_type data structure
for a TU to be read in directly from a DWO file, bypassing the stub.
This is the "Stay in DWO Optimization": When there is no DWP file and we're
using .gdb_index, then when reading a CU we want to stay in the DWO file
containing that CU. Otherwise we could end up reading several other DWO
files (due to comdat folding) to process the transitive closure of all the
mentioned TUs, and that can be slow. The current DWO file will have every
type signature that it needs.
We only do this for .gdb_index because in the psymtab case we already have
to read all the DWOs to build the type unit groups. */
static struct signatured_type *
lookup_dwo_signatured_type (struct dwarf2_cu *cu, ULONGEST sig)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
gdb_assert (cu->dwo_unit);
/* We only ever need to read in one copy of a signatured type.
Use the global signatured_types array to do our own comdat-folding
of types. If this is the first time we're reading this TU, and
the TU has an entry in .gdb_index, replace the recorded data from
.gdb_index with this TU. */
auto sig_type_it = per_bfd->signatured_types.find (sig);
/* We can get here with the TU already read, *or* in the process of being
read. Don't reassign the global entry to point to this DWO if that's
the case. Also note that if the TU is already being read, it may not
have come from a DWO, the program may be a mix of Fission-compiled
code and non-Fission-compiled code. */
/* Have we already tried to read this TU?
Note: sig_entry can be NULL if the skeleton TU was removed (thus it
needn't exist in the global table yet). */
if (sig_type_it != per_bfd->signatured_types.end ()
&& (*sig_type_it)->tu_read)
return *sig_type_it;
/* Note: cu->dwo_unit is the dwo_unit that references this TU, not the
dwo_unit of the TU itself. */
dwo_file *dwo_file = cu->dwo_unit->dwo_file;
auto it = dwo_file->tus.find (sig);
if (it == dwo_file->tus.end ())
return nullptr;
dwo_unit *dwo_entry = *it;
/* If the global table doesn't have an entry for this TU, add one. */
if (sig_type_it == per_bfd->signatured_types.end ())
sig_type_it = add_type_unit (per_bfd, dwo_entry->section,
dwo_entry->sect_off, dwo_entry->length, sig);
if ((*sig_type_it)->dwo_unit == nullptr)
fill_in_sig_entry_from_dwo_entry (per_objfile, *sig_type_it, dwo_entry);
(*sig_type_it)->tu_read = 1;
return *sig_type_it;
}
/* Subroutine of lookup_signatured_type.
Look up the type for signature SIG, and if we can't find SIG in .gdb_index
then try the DWP file. If the TU stub (skeleton) has been removed then
it won't be in .gdb_index. */
static struct signatured_type *
lookup_dwp_signatured_type (struct dwarf2_cu *cu, ULONGEST sig)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
struct dwp_file *dwp_file = get_dwp_file (per_objfile);
gdb_assert (cu->dwo_unit);
gdb_assert (dwp_file != NULL);
auto sig_type_it = per_bfd->signatured_types.find (sig);
/* Have we already tried to read this TU?
Note: sig_entry can be NULL if the skeleton TU was removed (thus it
needn't exist in the global table yet). */
if (sig_type_it != per_bfd->signatured_types.end ())
return *sig_type_it;
if (dwp_file->tus == NULL)
return NULL;
auto dwo_entry = lookup_dwo_unit_in_dwp (per_bfd, dwp_file, NULL, sig,
1 /* is_debug_types */);
if (dwo_entry == NULL)
return NULL;
sig_type_it = add_type_unit (per_bfd, dwo_entry->section,
dwo_entry->sect_off, dwo_entry->length, sig);
fill_in_sig_entry_from_dwo_entry (per_objfile, *sig_type_it, dwo_entry);
return *sig_type_it;
}
/* Lookup a signature based type for DW_FORM_ref_sig8.
Returns NULL if signature SIG is not present in the table.
It is up to the caller to complain about this. */
static struct signatured_type *
lookup_signatured_type (struct dwarf2_cu *cu, ULONGEST sig)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
if (cu->dwo_unit)
{
/* We're in a DWO/DWP file, and we're using .gdb_index.
These cases require special processing. */
if (get_dwp_file (per_objfile) == NULL)
return lookup_dwo_signatured_type (cu, sig);
else
return lookup_dwp_signatured_type (cu, sig);
}
else
{
auto sig_type_it = per_bfd->signatured_types.find (sig);
if (sig_type_it != per_bfd->signatured_types.end ())
return *sig_type_it;
return nullptr;
}
}
/* Low level DIE reading support. */
/* Initialize a cutu_reader from a dwarf2_cu. */
void
cutu_reader::init_cu_die_reader (dwarf2_cu *cu, dwarf2_section_info *section,
struct dwo_file *dwo_file,
const struct abbrev_table *abbrev_table)
{
gdb_assert (section->readin && section->buffer != NULL);
m_abfd = section->get_bfd_owner ();
m_cu = cu;
m_dwo_file = dwo_file;
m_die_section = section;
m_buffer = section->buffer;
m_buffer_end = section->buffer + section->size;
m_abbrev_table = abbrev_table;
}
/* Subroutine of cutu_reader to simplify it.
Read in the rest of a CU/TU top level DIE from DWO_UNIT.
There's just a lot of work to do, and cutu_reader is big enough
already.
STUB_COMP_UNIT_DIE is for the stub DIE, we copy over certain attributes
from it to the DIE in the DWO. If NULL we are skipping the stub.
STUB_COMP_DIR is similar to STUB_COMP_UNIT_DIE: When reading a TU directly
from the DWO file, bypassing the stub, it contains the DW_AT_comp_dir
attribute of the referencing CU. At most one of STUB_COMP_UNIT_DIE and
STUB_COMP_DIR may be non-NULL.
*RESULT_READER and *RESULT_TOP_LEVEL_DIE are filled in with the info of the
DIE from the DWO file.
*RESULT_DWO_ABBREV_TABLE will be filled in with the abbrev table allocated
from the dwo. Since *RESULT_READER references this abbrev table, it must be
kept around for at least as long as *RESULT_READER. */
void
cutu_reader::read_cutu_die_from_dwo (dwarf2_cu *cu, dwo_unit *dwo_unit,
die_info *stub_comp_unit_die,
const char *stub_comp_dir,
abbrev_table_up *result_dwo_abbrev_table)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
dwarf2_per_cu *per_cu = cu->per_cu;
struct objfile *objfile = per_objfile->objfile;
bfd *abfd;
struct dwarf2_section_info *dwo_abbrev_section;
/* At most one of these may be provided. */
gdb_assert ((stub_comp_unit_die != NULL) + (stub_comp_dir != NULL) <= 1);
/* These attributes aren't processed until later: DW_AT_stmt_list,
DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_comp_dir.
However, these attributes are found in the stub which we won't
have later. In order to not impose this complication on the rest
of the code, we read them here and copy them to the DWO CU/TU
die. */
/* We store them all in an array. */
struct attribute *attributes[5] {};
/* Next available element of the attributes array. */
int next_attr_idx = 0;
/* Push an element into ATTRIBUTES. */
auto push_back = [&] (struct attribute *attr)
{
gdb_assert (next_attr_idx < ARRAY_SIZE (attributes));
if (attr != nullptr)
attributes[next_attr_idx++] = attr;
};
if (stub_comp_unit_die != NULL)
{
/* For TUs in DWO files, the DW_AT_stmt_list attribute lives in the
DWO file. */
if (!per_cu->is_debug_types)
push_back (dwarf2_attr (stub_comp_unit_die, DW_AT_stmt_list, cu));
push_back (dwarf2_attr (stub_comp_unit_die, DW_AT_low_pc, cu));
push_back (dwarf2_attr (stub_comp_unit_die, DW_AT_high_pc, cu));
push_back (dwarf2_attr (stub_comp_unit_die, DW_AT_ranges, cu));
push_back (dwarf2_attr (stub_comp_unit_die, DW_AT_comp_dir, cu));
cu->addr_base = stub_comp_unit_die->addr_base ();
/* There should be a DW_AT_GNU_ranges_base attribute here (if needed).
We need the value before we can process DW_AT_ranges values from the
DWO. */
cu->gnu_ranges_base = stub_comp_unit_die->gnu_ranges_base ();
/* For DWARF5: record the DW_AT_rnglists_base value from the skeleton. If
there are attributes of form DW_FORM_rnglistx in the skeleton, they'll
need the rnglists base. Attributes of form DW_FORM_rnglistx in the
split unit don't use it, as the DWO has its own .debug_rnglists.dwo
section. */
cu->rnglists_base = stub_comp_unit_die->rnglists_base ();
}
else if (stub_comp_dir != NULL)
{
/* Reconstruct the comp_dir attribute to simplify the code below. */
struct attribute *comp_dir = OBSTACK_ZALLOC (&cu->comp_unit_obstack,
struct attribute);
comp_dir->name = DW_AT_comp_dir;
comp_dir->form = DW_FORM_string;
comp_dir->set_string_noncanonical (stub_comp_dir);
push_back (comp_dir);
}
/* Set up for reading the DWO CU/TU. */
cu->dwo_unit = dwo_unit;
dwarf2_section_info *section = dwo_unit->section;
section->read (objfile);
abfd = section->get_bfd_owner ();
m_info_ptr = section->buffer + to_underlying (dwo_unit->sect_off);
const gdb_byte *begin_info_ptr = m_info_ptr;
dwo_abbrev_section = &dwo_unit->dwo_file->sections.abbrev;
if (per_cu->is_debug_types)
{
signatured_type *sig_type = (struct signatured_type *) per_cu;
m_info_ptr = read_and_check_comp_unit_head (per_objfile, &cu->header,
section, dwo_abbrev_section,
m_info_ptr, rcuh_kind::TYPE);
/* This is not an assert because it can be caused by bad debug info. */
if (sig_type->signature != cu->header.signature)
{
error (_(DWARF_ERROR_PREFIX
"signature mismatch %s vs %s while reading TU at offset %s"
" [in module %s]"),
hex_string (sig_type->signature),
hex_string (cu->header.signature),
sect_offset_str (dwo_unit->sect_off),
bfd_get_filename (abfd));
}
gdb_assert (dwo_unit->sect_off == cu->header.sect_off);
/* For DWOs coming from DWP files, we don't know the CU length
nor the type's offset in the TU until now. */
dwo_unit->length = cu->header.get_length_with_initial ();
dwo_unit->type_offset_in_tu = cu->header.type_cu_offset_in_tu;
/* Establish the type offset that can be used to lookup the type.
For DWO files, we don't know it until now. */
sig_type->type_offset_in_section
= dwo_unit->sect_off + to_underlying (dwo_unit->type_offset_in_tu);
}
else
{
m_info_ptr
= read_and_check_comp_unit_head (per_objfile, &cu->header, section,
dwo_abbrev_section, m_info_ptr,
rcuh_kind::COMPILE);
gdb_assert (dwo_unit->sect_off == cu->header.sect_off);
/* For DWOs coming from DWP files, we don't know the CU length
until now. */
dwo_unit->length = cu->header.get_length_with_initial ();
}
dwo_abbrev_section->read (objfile);
*result_dwo_abbrev_table
= abbrev_table::read (dwo_abbrev_section, cu->header.abbrev_sect_off);
this->init_cu_die_reader (cu, section, dwo_unit->dwo_file,
result_dwo_abbrev_table->get ());
/* Read in the die, filling in the attributes from the stub. This
has the benefit of simplifying the rest of the code - all the
work to maintain the illusion of a single
DW_TAG_{compile,type}_unit DIE is done here. */
m_top_level_die
= this->read_toplevel_die (gdb::make_array_view (attributes,
next_attr_idx));
/* Skip dummy compilation units. */
if (m_info_ptr >= begin_info_ptr + dwo_unit->length
|| peek_abbrev_code (abfd, m_info_ptr) == 0)
m_dummy_p = true;
}
/* Return the signature of the compile unit, if found. In DWARF 4 and before,
the signature is in the DW_AT_GNU_dwo_id attribute. In DWARF 5 and later, the
signature is part of the header. */
static std::optional<ULONGEST>
lookup_dwo_id (struct dwarf2_cu *cu, struct die_info* comp_unit_die)
{
if (cu->header.version >= 5)
return cu->header.signature;
struct attribute *attr;
attr = dwarf2_attr (comp_unit_die, DW_AT_GNU_dwo_id, cu);
if (attr == nullptr || !attr->form_is_unsigned ())
return std::optional<ULONGEST> ();
return attr->as_unsigned ();
}
/* Subroutine of cutu_reader to simplify it.
Look up the DWO unit specified by COMP_UNIT_DIE of THIS_CU.
Returns NULL if the specified DWO unit cannot be found. */
static struct dwo_unit *
lookup_dwo_unit (dwarf2_cu *cu, die_info *comp_unit_die, const char *dwo_name)
{
#if CXX_STD_THREAD
/* We need a lock here to handle the DWO hash table. */
static std::mutex dwo_lock;
std::lock_guard<std::mutex> guard (dwo_lock);
#endif
dwarf2_per_cu *per_cu = cu->per_cu;
struct dwo_unit *dwo_unit;
const char *comp_dir;
gdb_assert (cu != NULL);
/* Yeah, we look dwo_name up again, but it simplifies the code. */
dwo_name = dwarf2_dwo_name (comp_unit_die, cu);
comp_dir = dwarf2_string_attr (comp_unit_die, DW_AT_comp_dir, cu);
if (per_cu->is_debug_types)
dwo_unit = lookup_dwo_type_unit (cu, dwo_name, comp_dir);
else
{
std::optional<ULONGEST> signature = lookup_dwo_id (cu, comp_unit_die);
if (!signature.has_value ())
error (_(DWARF_ERROR_PREFIX
"missing dwo_id for dwo_name %s"
" [in module %s]"),
dwo_name, per_cu->per_bfd->filename ());
dwo_unit = lookup_dwo_comp_unit (cu, dwo_name, comp_dir, *signature);
}
return dwo_unit;
}
/* Subroutine of cutu_reader to simplify it.
See it for a description of the parameters.
Read a TU directly from a DWO file, bypassing the stub. */
void
cutu_reader::init_tu_and_read_dwo_dies (dwarf2_per_cu *this_cu,
dwarf2_per_objfile *per_objfile,
dwarf2_cu *existing_cu,
enum language pretend_language)
{
struct signatured_type *sig_type;
/* Verify we can do the following downcast, and that we have the
data we need. */
gdb_assert (this_cu->is_debug_types && this_cu->reading_dwo_directly);
sig_type = (struct signatured_type *) this_cu;
gdb_assert (sig_type->dwo_unit != NULL);
dwarf2_cu *cu;
if (existing_cu != nullptr)
{
cu = existing_cu;
gdb_assert (cu->dwo_unit == sig_type->dwo_unit);
/* There's no need to do the rereading_dwo_cu handling that
cutu_reader does since we don't read the stub. */
}
else
{
/* If an existing_cu is provided, a dwarf2_cu must not exist for this_cu
in per_objfile yet. */
gdb_assert (per_objfile->get_cu (this_cu) == nullptr);
m_new_cu = std::make_unique<dwarf2_cu> (this_cu, per_objfile);
cu = m_new_cu.get ();
}
/* A future optimization, if needed, would be to use an existing
abbrev table. When reading DWOs with skeletonless TUs, all the TUs
could share abbrev tables. */
read_cutu_die_from_dwo (cu, sig_type->dwo_unit, NULL /* stub_comp_unit_die */,
sig_type->dwo_unit->dwo_file->comp_dir,
&m_dwo_abbrev_table);
prepare_one_comp_unit (cu, pretend_language);
}
/* Initialize a CU (or TU) and read its DIEs.
If the CU defers to a DWO file, read the DWO file as well.
ABBREV_TABLE, if non-NULL, is the abbreviation table to use.
Otherwise the table specified in the comp unit header is read in and used.
This is an optimization for when we already have the abbrev table.
If EXISTING_CU is non-NULL, then use it. Otherwise, a new CU is
allocated. */
cutu_reader::cutu_reader (dwarf2_per_cu *this_cu,
dwarf2_per_objfile *per_objfile,
const struct abbrev_table *abbrev_table,
dwarf2_cu *existing_cu,
bool skip_partial,
enum language pretend_language,
const abbrev_table_cache *cache)
{
struct objfile *objfile = per_objfile->objfile;
struct dwarf2_section_info *section = this_cu->section;
bfd *abfd = section->get_bfd_owner ();
const gdb_byte *begin_info_ptr;
struct signatured_type *sig_type = NULL;
struct dwarf2_section_info *abbrev_section;
/* Non-zero if CU currently points to a DWO file and we need to
reread it. When this happens we need to reread the skeleton die
before we can reread the DWO file (this only applies to CUs, not TUs). */
int rereading_dwo_cu = 0;
if (dwarf_die_debug)
gdb_printf (gdb_stdlog, "Reading %s unit at offset %s\n",
this_cu->is_debug_types ? "type" : "comp",
sect_offset_str (this_cu->sect_off));
/* If we're reading a TU directly from a DWO file, including a virtual DWO
file (instead of going through the stub), short-circuit all of this. */
if (this_cu->reading_dwo_directly)
{
/* Narrow down the scope of possibilities to have to understand. */
gdb_assert (this_cu->is_debug_types);
gdb_assert (abbrev_table == NULL);
init_tu_and_read_dwo_dies (this_cu, per_objfile, existing_cu,
pretend_language);
return;
}
/* This is cheap if the section is already read in. */
section->read (objfile);
begin_info_ptr = m_info_ptr
= section->buffer + to_underlying (this_cu->sect_off);
abbrev_section = get_abbrev_section_for_cu (this_cu);
dwarf2_cu *cu;
if (existing_cu != nullptr)
{
cu = existing_cu;
/* If this CU is from a DWO file we need to start over, we need to
refetch the attributes from the skeleton CU.
This could be optimized by retrieving those attributes from when we
were here the first time: the previous comp_unit_die was stored in
comp_unit_obstack. But there's no data yet that we need this
optimization. */
if (cu->dwo_unit != NULL)
rereading_dwo_cu = 1;
}
else
{
/* If an existing_cu is provided, a dwarf2_cu must not exist for
this_cu in per_objfile yet. Here, CACHE doubles as a flag to
let us know that the CU is being scanned using the parallel
indexer. This assert is avoided in this case because (1) it
is irrelevant, and (2) the get_cu method is not
thread-safe. */
gdb_assert (cache != nullptr
|| per_objfile->get_cu (this_cu) == nullptr);
m_new_cu = std::make_unique<dwarf2_cu> (this_cu, per_objfile);
cu = m_new_cu.get ();
}
/* Get the header. */
if (to_underlying (cu->header.first_die_cu_offset) != 0 && !rereading_dwo_cu)
{
/* We already have the header, there's no need to read it in again. */
m_info_ptr += to_underlying (cu->header.first_die_cu_offset);
}
else
{
if (this_cu->is_debug_types)
{
m_info_ptr
= read_and_check_comp_unit_head (per_objfile, &cu->header, section,
abbrev_section, m_info_ptr,
rcuh_kind::TYPE);
/* Since per_cu is the first member of struct signatured_type,
we can go from a pointer to one to a pointer to the other. */
sig_type = (struct signatured_type *) this_cu;
gdb_assert (sig_type->signature == cu->header.signature);
gdb_assert (sig_type->type_offset_in_tu
== cu->header.type_cu_offset_in_tu);
gdb_assert (this_cu->sect_off == cu->header.sect_off);
/* LENGTH has not been set yet for type units if we're
using .gdb_index. */
this_cu->set_length (cu->header.get_length_with_initial ());
/* Establish the type offset that can be used to lookup the type. */
sig_type->type_offset_in_section =
this_cu->sect_off + to_underlying (sig_type->type_offset_in_tu);
}
else
{
m_info_ptr
= read_and_check_comp_unit_head (per_objfile, &cu->header, section,
abbrev_section, m_info_ptr,
rcuh_kind::COMPILE);
gdb_assert (this_cu->sect_off == cu->header.sect_off);
this_cu->set_length (cu->header.get_length_with_initial ());
}
}
/* Skip dummy compilation units. */
if (m_info_ptr >= begin_info_ptr + this_cu->length ()
|| peek_abbrev_code (abfd, m_info_ptr) == 0)
m_dummy_p = true;
else
{
/* If we don't have them yet, read the abbrevs for this
compilation unit. And if we need to read them now, make sure
they're freed when we're done. */
if (abbrev_table != NULL)
gdb_assert (cu->header.abbrev_sect_off == abbrev_table->sect_off);
else
{
if (cache != nullptr)
abbrev_table = cache->find (abbrev_section,
cu->header.abbrev_sect_off);
if (abbrev_table == nullptr)
{
abbrev_section->read (objfile);
m_abbrev_table_holder
= abbrev_table::read (abbrev_section,
cu->header.abbrev_sect_off);
abbrev_table = m_abbrev_table_holder.get ();
}
}
/* Read the top level CU/TU die. */
this->init_cu_die_reader (cu, section, NULL, abbrev_table);
m_top_level_die = this->read_toplevel_die ();
if (skip_partial && m_top_level_die->tag == DW_TAG_partial_unit)
m_dummy_p = true;
else
{
/* If we are in a DWO stub, process it and then read in the
"real" CU/TU from the DWO file. read_cutu_die_from_dwo
will allocate the abbreviation table from the DWO file
and pass the ownership over to us. It will be referenced
from READER, so we must make sure to free it after we're
done with READER.
Note that if USE_EXISTING_OK != 0, and THIS_CU->cu
already contains a DWO CU, that this test will fail (the
attribute will not be present). */
const char *dwo_name = dwarf2_dwo_name (m_top_level_die, cu);
if (dwo_name != nullptr)
{
struct dwo_unit *dwo_unit;
if (m_top_level_die->has_children)
{
complaint (_("compilation unit with DW_AT_GNU_dwo_name"
" has children (offset %s) [in module %s]"),
sect_offset_str (this_cu->sect_off),
bfd_get_filename (abfd));
}
dwo_unit = lookup_dwo_unit (cu, m_top_level_die, dwo_name);
if (dwo_unit != NULL)
read_cutu_die_from_dwo (cu, dwo_unit, m_top_level_die, nullptr,
&m_dwo_abbrev_table);
else
{
/* Yikes, we couldn't find the rest of the DIE, we only have
the stub. A complaint has already been logged. There's
not much more we can do except pass on the stub DIE to
die_reader_func. We don't want to throw an error on bad
debug info. */
}
}
}
}
/* Only a dummy unit can be missing the compunit DIE. */
gdb_assert (m_dummy_p || m_top_level_die != nullptr);
prepare_one_comp_unit (cu, pretend_language);
}
/* See read.h. */
dwarf2_cu_up
cutu_reader::release_cu ()
{
gdb_assert (!m_dummy_p);
gdb_assert (m_new_cu != nullptr);
return std::move (m_new_cu);
}
/* Read CU/TU THIS_CU but do not follow DW_AT_GNU_dwo_name (DW_AT_dwo_name)
if present. DWO_FILE, if non-NULL, is the DWO file to read (the caller is
assumed to have already done the lookup to find the DWO file).
The caller is required to fill in THIS_CU->section, THIS_CU->offset, and
THIS_CU->is_debug_types, but nothing else.
We fill in THIS_CU->length.
THIS_CU->cu is always freed when done.
This is done in order to not leave THIS_CU->cu in a state where we have
to care whether it refers to the "main" CU or the DWO CU.
When parent_cu is passed, it is used to provide a default value for
str_offsets_base and addr_base from the parent. */
cutu_reader::cutu_reader (dwarf2_per_cu *this_cu,
dwarf2_per_objfile *per_objfile,
enum language pretend_language,
struct dwarf2_cu *parent_cu,
struct dwo_file *dwo_file)
{
struct objfile *objfile = per_objfile->objfile;
struct dwarf2_section_info *section = this_cu->section;
bfd *abfd = section->get_bfd_owner ();
gdb_assert (parent_cu != nullptr);
gdb_assert (dwo_file != nullptr);
if (dwarf_die_debug)
gdb_printf (gdb_stdlog, "Reading %s unit at offset %s\n",
this_cu->is_debug_types ? "type" : "comp",
sect_offset_str (this_cu->sect_off));
gdb_assert (per_objfile->get_cu (this_cu) == nullptr);
dwarf2_section_info *abbrev_section = &dwo_file->sections.abbrev;
/* This is cheap if the section is already read in. */
section->read (objfile);
m_new_cu = std::make_unique<dwarf2_cu> (this_cu, per_objfile);
m_info_ptr = section->buffer + to_underlying (this_cu->sect_off);
const gdb_byte *begin_info_ptr = m_info_ptr;
m_info_ptr
= read_and_check_comp_unit_head (per_objfile, &m_new_cu->header, section,
abbrev_section, m_info_ptr,
(this_cu->is_debug_types
? rcuh_kind::TYPE
: rcuh_kind::COMPILE));
m_new_cu->str_offsets_base = parent_cu->str_offsets_base;
m_new_cu->addr_base = parent_cu->addr_base;
this_cu->set_length (m_new_cu->header.get_length_with_initial ());
/* Skip dummy compilation units. */
if (m_info_ptr >= begin_info_ptr + this_cu->length ()
|| peek_abbrev_code (abfd, m_info_ptr) == 0)
m_dummy_p = true;
else
{
abbrev_section->read (objfile);
m_abbrev_table_holder
= abbrev_table::read (abbrev_section,
m_new_cu->header.abbrev_sect_off);
this->init_cu_die_reader (m_new_cu.get (), section, dwo_file,
m_abbrev_table_holder.get ());
m_top_level_die = this->read_toplevel_die ();
}
prepare_one_comp_unit (m_new_cu.get (), pretend_language);
}
/* Type Unit Groups.
Type Unit Groups are a way to collapse the set of all TUs (type units) into
a more manageable set. The grouping is done by DW_AT_stmt_list entry
so that all types coming from the same compilation (.o file) are grouped
together. A future step could be to put the types in the same symtab as
the CU the types ultimately came from. */
/* Type units that don't have DW_AT_stmt_list are grouped into their own
partial symtabs. We combine several TUs per psymtab to not let the size
of any one psymtab grow too big. */
#define NO_STMT_LIST_TYPE_UNIT_PSYMTAB (1 << 31)
#define NO_STMT_LIST_TYPE_UNIT_PSYMTAB_SIZE 10
/* Get the type unit group key for type unit CU. STMT_LIST is a DW_AT_stmt_list
attribute. */
static stmt_list_hash
get_type_unit_group_key (struct dwarf2_cu *cu, const struct attribute *stmt_list)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct tu_stats *tu_stats = &per_objfile->per_bfd->tu_stats;
unsigned int line_offset;
/* Do we need to create a new group, or can we use an existing one? */
if (stmt_list != nullptr && stmt_list->form_is_unsigned ())
{
line_offset = stmt_list->as_unsigned ();
++tu_stats->nr_symtab_sharers;
}
else
{
/* Ugh, no stmt_list. Rare, but we have to handle it.
We can do various things here like create one group per TU or
spread them over multiple groups to split up the expansion work.
To avoid worst case scenarios (too many groups or too large groups)
we, umm, group them in bunches. */
line_offset = (NO_STMT_LIST_TYPE_UNIT_PSYMTAB
| (tu_stats->nr_stmt_less_type_units
/ NO_STMT_LIST_TYPE_UNIT_PSYMTAB_SIZE));
++tu_stats->nr_stmt_less_type_units;
}
return {cu->dwo_unit, static_cast<sect_offset> (line_offset)};
}
/* Subroutine of dwarf2_build_psymtabs_hard to simplify it.
Process compilation unit THIS_CU for a psymtab. */
static void
process_psymtab_comp_unit (dwarf2_per_cu *this_cu,
dwarf2_per_objfile *per_objfile,
cooked_index_storage *storage)
{
cutu_reader *reader = storage->get_reader (this_cu);
if (reader == nullptr)
{
cutu_reader new_reader (this_cu, per_objfile, nullptr, nullptr, false,
language_minimal,
&storage->get_abbrev_table_cache ());
if (new_reader.cu () == nullptr || new_reader.is_dummy ())
return;
auto copy = std::make_unique<cutu_reader> (std::move (new_reader));
reader = storage->preserve (std::move (copy));
}
if (reader->top_level_die () == nullptr || reader->is_dummy ())
return;
if (this_cu->is_debug_types)
build_type_psymtabs_reader (reader, storage);
else if (reader->top_level_die ()->tag != DW_TAG_partial_unit)
{
bool nope = false;
if (this_cu->scanned.compare_exchange_strong (nope, true))
{
gdb_assert (storage != nullptr);
cooked_indexer indexer (storage, this_cu, reader->cu ()->lang ());
indexer.make_index (reader);
}
}
}
/* Reader function for build_type_psymtabs. */
static void
build_type_psymtabs_reader (cutu_reader *reader,
cooked_index_storage *storage)
{
struct dwarf2_cu *cu = reader->cu ();
dwarf2_per_cu *per_cu = cu->per_cu;
die_info *type_unit_die = reader->top_level_die ();
gdb_assert (per_cu->is_debug_types);
if (! type_unit_die->has_children)
return;
gdb_assert (storage != nullptr);
cooked_indexer indexer (storage, per_cu, cu->lang ());
indexer.make_index (reader);
}
/* Struct used to sort TUs by their abbreviation table offset. */
struct tu_abbrev_offset
{
tu_abbrev_offset (signatured_type *sig_type_, sect_offset abbrev_offset_)
: sig_type (sig_type_), abbrev_offset (abbrev_offset_)
{}
/* This is used when sorting. */
bool operator< (const tu_abbrev_offset &other) const
{
return abbrev_offset < other.abbrev_offset;
}
signatured_type *sig_type;
sect_offset abbrev_offset;
};
/* Efficiently read all the type units.
The efficiency is because we sort TUs by the abbrev table they use and
only read each abbrev table once. In one program there are 200K TUs
sharing 8K abbrev tables.
The main purpose of this function is to support building the
dwarf2_per_objfile->per_bfd->type_unit_groups table.
TUs typically share the DW_AT_stmt_list of the CU they came from, so we
can collapse the search space by grouping them by stmt_list.
The savings can be significant, in the same program from above the 200K TUs
share 8K stmt_list tables.
FUNC is expected to call get_type_unit_group, which will create the
struct type_unit_group if necessary and add it to
dwarf2_per_objfile->per_bfd->type_unit_groups. */
static void
build_type_psymtabs (dwarf2_per_objfile *per_objfile,
cooked_index_storage *storage)
{
struct tu_stats *tu_stats = &per_objfile->per_bfd->tu_stats;
abbrev_table_up abbrev_table;
sect_offset abbrev_offset;
if (per_objfile->per_bfd->all_type_units.size () == 0)
return;
/* TUs typically share abbrev tables, and there can be way more TUs than
abbrev tables. Sort by abbrev table to reduce the number of times we
read each abbrev table in.
Alternatives are to punt or to maintain a cache of abbrev tables.
This is simpler and efficient enough for now.
Later we group TUs by their DW_AT_stmt_list value (as this defines the
symtab to use). Typically TUs with the same abbrev offset have the same
stmt_list value too so in practice this should work well.
The basic algorithm here is:
sort TUs by abbrev table
for each TU with same abbrev table:
read abbrev table if first user
read TU top level DIE
[IWBN if DWO skeletons had DW_AT_stmt_list]
call FUNC */
dwarf_read_debug_printf ("Building type unit groups ...");
/* Sort in a separate table to maintain the order of all_units
for .gdb_index: TU indices directly index all_type_units. */
std::vector<tu_abbrev_offset> sorted_by_abbrev;
sorted_by_abbrev.reserve (per_objfile->per_bfd->all_type_units.size ());
for (const auto &cu : per_objfile->per_bfd->all_units)
if (cu->is_debug_types)
{
auto sig_type = static_cast<signatured_type *> (cu.get ());
sorted_by_abbrev.emplace_back (sig_type,
read_abbrev_offset (per_objfile,
sig_type->section,
sig_type->sect_off));
}
std::sort (sorted_by_abbrev.begin (), sorted_by_abbrev.end ());
abbrev_offset = (sect_offset) ~(unsigned) 0;
for (const tu_abbrev_offset &tu : sorted_by_abbrev)
{
/* Switch to the next abbrev table if necessary. */
if (abbrev_table == NULL
|| tu.abbrev_offset != abbrev_offset)
{
abbrev_offset = tu.abbrev_offset;
per_objfile->per_bfd->abbrev.read (per_objfile->objfile);
abbrev_table =
abbrev_table::read (&per_objfile->per_bfd->abbrev, abbrev_offset);
++tu_stats->nr_uniq_abbrev_tables;
}
cutu_reader reader (tu.sig_type, per_objfile,
abbrev_table.get (), nullptr, false,
language_minimal);
if (!reader.is_dummy ())
build_type_psymtabs_reader (&reader, storage);
}
}
/* Print collected type unit statistics. */
static void
print_tu_stats (dwarf2_per_objfile *per_objfile)
{
struct tu_stats *tu_stats = &per_objfile->per_bfd->tu_stats;
dwarf_read_debug_printf ("Type unit statistics:");
dwarf_read_debug_printf (" %d TUs", tu_stats->nr_tus);
dwarf_read_debug_printf (" %d uniq abbrev tables",
tu_stats->nr_uniq_abbrev_tables);
dwarf_read_debug_printf (" %d symtabs from stmt_list entries",
tu_stats->nr_symtabs);
dwarf_read_debug_printf (" %d symtab sharers",
tu_stats->nr_symtab_sharers);
dwarf_read_debug_printf (" %d type units without a stmt_list",
tu_stats->nr_stmt_less_type_units);
dwarf_read_debug_printf (" %d all_type_units reallocs",
tu_stats->nr_all_type_units_reallocs);
}
/* Traversal function for process_skeletonless_type_units.
Read a TU in a DWO file and build partial symbols for it. */
static void
process_skeletonless_type_unit (dwo_unit *dwo_unit,
dwarf2_per_objfile *per_objfile,
cooked_index_storage *storage)
{
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
/* If this TU doesn't exist in the global table, add it and read it in. */
auto sig_type_it = per_bfd->signatured_types.find (dwo_unit->signature);
/* If we've already seen this type there's nothing to do. What's happening
is we're doing our own version of comdat-folding here. */
if (sig_type_it != per_bfd->signatured_types.end ())
return;
/* This does the job that create_all_units would have done for
this TU. */
sig_type_it = add_type_unit (per_bfd, dwo_unit->section, dwo_unit->sect_off,
dwo_unit->length, dwo_unit->signature);
fill_in_sig_entry_from_dwo_entry (per_objfile, *sig_type_it, dwo_unit);
/* This does the job that build_type_psymtabs would have done. */
cutu_reader reader (*sig_type_it, per_objfile, nullptr, nullptr, false,
language_minimal);
if (!reader.is_dummy ())
build_type_psymtabs_reader (&reader, storage);
}
/* Scan all TUs of DWO files, verifying we've processed them.
This is needed in case a TU was emitted without its skeleton.
Note: This can't be done until we know what all the DWO files are. */
static void
process_skeletonless_type_units (dwarf2_per_objfile *per_objfile,
cooked_index_storage *storage)
{
/* Skeletonless TUs in DWP files without .gdb_index is not supported yet. */
if (get_dwp_file (per_objfile) == nullptr)
for (const dwo_file_up &file : per_objfile->per_bfd->dwo_files)
for (dwo_unit *unit : file->tus)
process_skeletonless_type_unit (unit, per_objfile, storage);
}
/* A subclass of cooked_index_worker that handles scanning
.debug_info. */
class cooked_index_worker_debug_info : public cooked_index_worker
{
public:
cooked_index_worker_debug_info (dwarf2_per_objfile *per_objfile)
: cooked_index_worker (per_objfile)
{
gdb_assert (is_main_thread ());
struct objfile *objfile = per_objfile->objfile;
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
dwarf_read_debug_printf ("Building psymtabs of objfile %s ...",
objfile_name (objfile));
per_bfd->map_info_sections (objfile);
}
private:
void do_reading () override;
void print_stats () override
{
if (dwarf_read_debug > 0)
print_tu_stats (m_per_objfile);
if (dwarf_read_debug > 1)
{
dwarf_read_debug_printf_v ("Final m_all_parents_map:");
m_all_parents_map.dump (m_per_objfile->per_bfd);
}
}
/* After the last DWARF-reading task has finished, this function
does the remaining work to finish the scan. */
void done_reading ();
/* An iterator for the comp units. */
using unit_iterator = std::vector<dwarf2_per_cu_up>::iterator;
/* Process a batch of CUs. This may be called multiple times in
separate threads. TASK_NUMBER indicates which task this is --
the result is stored in that slot of M_RESULTS. */
void process_cus (size_t task_number, unit_iterator first,
unit_iterator end);
/* A storage object for "leftovers" -- see the 'start' method, but
essentially things not parsed during the normal CU parsing
passes. */
cooked_index_storage m_index_storage;
};
void
cooked_index_worker_debug_info::process_cus (size_t task_number, unit_iterator first,
unit_iterator end)
{
SCOPE_EXIT { bfd_thread_cleanup (); };
/* Ensure that complaints are handled correctly. */
complaint_interceptor complaint_handler;
std::vector<gdb_exception> errors;
cooked_index_storage thread_storage;
for (auto inner = first; inner != end; ++inner)
{
dwarf2_per_cu *per_cu = inner->get ();
try
{
process_psymtab_comp_unit (per_cu, m_per_objfile, &thread_storage);
}
catch (gdb_exception &except)
{
errors.push_back (std::move (except));
}
}
m_results[task_number] = result_type (thread_storage.release (),
complaint_handler.release (),
std::move (errors),
thread_storage.release_parent_map ());
}
void
cooked_index_worker_debug_info::done_reading ()
{
/* Only handle the scanning results here. Complaints and exceptions
can only be dealt with on the main thread. */
std::vector<cooked_index_shard_up> shards;
for (auto &one_result : m_results)
{
shards.push_back (std::move (std::get<0> (one_result)));
m_all_parents_map.add_map (std::get<3> (one_result));
}
/* This has to wait until we read the CUs, we need the list of DWOs. */
process_skeletonless_type_units (m_per_objfile, &m_index_storage);
shards.push_back (m_index_storage.release ());
shards.shrink_to_fit ();
m_all_parents_map.add_map (m_index_storage.release_parent_map ());
dwarf2_per_bfd *per_bfd = m_per_objfile->per_bfd;
cooked_index *table
= (gdb::checked_static_cast<cooked_index *>
(per_bfd->index_table.get ()));
table->set_contents (std::move (shards), &m_warnings,
&m_all_parents_map);
}
void
cooked_index_worker_debug_info::do_reading ()
{
dwarf2_per_bfd *per_bfd = m_per_objfile->per_bfd;
create_all_units (m_per_objfile);
build_type_psymtabs (m_per_objfile, &m_index_storage);
if (!per_bfd->debug_aranges.empty ())
read_addrmap_from_aranges (m_per_objfile, &per_bfd->debug_aranges,
m_index_storage.get_addrmap (),
&m_warnings);
/* We want to balance the load between the worker threads. This is
done by using the size of each CU as a rough estimate of how
difficult it will be to operate on. This isn't ideal -- for
example if dwz is used, the early CUs will all tend to be
"included" and won't be parsed independently. However, this
heuristic works well for typical compiler output. */
size_t total_size = 0;
for (const auto &per_cu : per_bfd->all_units)
total_size += per_cu->length ();
/* How many worker threads we plan to use. We may not actually use
this many. We use 1 as the minimum to avoid division by zero,
and anyway in the N==0 case the work will be done
synchronously. */
const size_t n_worker_threads
= std::max (gdb::thread_pool::g_thread_pool->thread_count (), (size_t) 1);
/* How much effort should be put into each worker. */
const size_t size_per_thread
= std::max (total_size / n_worker_threads, (size_t) 1);
/* Work is done in a task group. */
gdb::task_group workers ([this] ()
{
this->done_reading ();
});
auto end = per_bfd->all_units.end ();
size_t task_count = 0;
for (auto iter = per_bfd->all_units.begin (); iter != end; )
{
auto last = iter;
/* Put all remaining CUs into the last task. */
if (task_count == n_worker_threads - 1)
last = end;
else
{
size_t chunk_size = 0;
for (; last != end && chunk_size < size_per_thread; ++last)
chunk_size += (*last)->length ();
}
gdb_assert (iter != last);
workers.add_task ([this, task_count, iter, last] ()
{
process_cus (task_count, iter, last);
});
++task_count;
iter = last;
}
m_results.resize (task_count);
workers.start ();
}
static void
read_comp_units_from_section (dwarf2_per_objfile *per_objfile,
struct dwarf2_section_info *section,
struct dwarf2_section_info *abbrev_section,
unsigned int is_dwz,
signatured_type_set &sig_types,
rcuh_kind section_kind)
{
const gdb_byte *info_ptr;
struct objfile *objfile = per_objfile->objfile;
dwarf_read_debug_printf ("Reading %s for %s",
section->get_name (),
section->get_file_name ());
section->read (objfile);
info_ptr = section->buffer;
while (info_ptr < section->buffer + section->size)
{
dwarf2_per_cu_up this_cu;
sect_offset sect_off = (sect_offset) (info_ptr - section->buffer);
comp_unit_head cu_header;
read_and_check_comp_unit_head (per_objfile, &cu_header, section,
abbrev_section, info_ptr,
section_kind);
unsigned int length = cu_header.get_length_with_initial ();
/* Save the compilation unit for later lookup. */
if (cu_header.unit_type != DW_UT_type)
this_cu
= per_objfile->per_bfd->allocate_per_cu (section, sect_off, length, is_dwz);
else
{
auto sig_type = per_objfile->per_bfd->allocate_signatured_type
(section, sect_off, length, is_dwz, cu_header.signature);
signatured_type *sig_ptr = sig_type.get ();
sig_type->type_offset_in_tu = cu_header.type_cu_offset_in_tu;
this_cu.reset (sig_type.release ());
auto inserted = sig_types.emplace (sig_ptr).second;
if (!inserted)
complaint (_("debug type entry at offset %s is duplicate to"
" the entry at offset %s, signature %s"),
sect_offset_str (sect_off),
sect_offset_str (sig_ptr->sect_off),
hex_string (sig_ptr->signature));
}
info_ptr = info_ptr + this_cu->length ();
per_objfile->per_bfd->all_units.push_back (std::move (this_cu));
}
}
/* Initialize the views on all_units. */
void
finalize_all_units (dwarf2_per_bfd *per_bfd)
{
size_t nr_tus = per_bfd->tu_stats.nr_tus;
size_t nr_cus = per_bfd->all_units.size () - nr_tus;
gdb::array_view<dwarf2_per_cu_up> tmp = per_bfd->all_units;
per_bfd->all_comp_units = tmp.slice (0, nr_cus);
per_bfd->all_type_units = tmp.slice (nr_cus, nr_tus);
}
/* See read.h. */
void
create_all_units (dwarf2_per_objfile *per_objfile)
{
gdb_assert (per_objfile->per_bfd->all_units.empty ());
signatured_type_set sig_types;
for (dwarf2_section_info &section : per_objfile->per_bfd->infos)
read_comp_units_from_section (per_objfile, &section,
&per_objfile->per_bfd->abbrev, 0, sig_types,
rcuh_kind::COMPILE);
for (dwarf2_section_info &section : per_objfile->per_bfd->types)
read_comp_units_from_section (per_objfile, &section,
&per_objfile->per_bfd->abbrev, 0, sig_types,
rcuh_kind::TYPE);
dwz_file *dwz = per_objfile->per_bfd->get_dwz_file ();
if (dwz != NULL)
{
read_comp_units_from_section (per_objfile, &dwz->info, &dwz->abbrev, 1,
sig_types, rcuh_kind::COMPILE);
if (!dwz->types.empty ())
{
per_objfile->per_bfd->all_units.clear ();
/* See enhancement PR symtab/30838. */
error (_(DWARF_ERROR_PREFIX
".debug_types section not supported in dwz file"));
}
}
per_objfile->per_bfd->signatured_types = std::move (sig_types);
finalize_all_units (per_objfile->per_bfd);
}
/* Return the initial uleb128 in the die at INFO_PTR. */
static unsigned int
peek_abbrev_code (bfd *abfd, const gdb_byte *info_ptr)
{
unsigned int bytes_read;
return read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
}
/* Read the initial uleb128 in the die at INFO_PTR in compilation unit
READER::CU. Use READER::ABBREV_TABLE to lookup any abbreviation.
Return the corresponding abbrev, or NULL if the number is zero (indicating
an empty DIE). In either case *BYTES_READ will be set to the length of
the initial number. */
const abbrev_info *
cutu_reader::peek_die_abbrev (const gdb_byte *info_ptr,
unsigned int *bytes_read)
{
unsigned int abbrev_number
= read_unsigned_leb128 (m_abfd, info_ptr, bytes_read);
if (abbrev_number == 0)
return NULL;
const abbrev_info *abbrev = m_abbrev_table->lookup_abbrev (abbrev_number);
if (!abbrev)
{
error (_(DWARF_ERROR_PREFIX
"Could not find abbrev number %d in %s at offset %s"
" [in module %s]"),
abbrev_number, m_cu->per_cu->is_debug_types ? "TU" : "CU",
sect_offset_str (m_cu->header.sect_off),
bfd_get_filename (m_abfd));
}
return abbrev;
}
/* Scan the debug information for CU starting at INFO_PTR in buffer BUFFER.
Returns a pointer to the end of a series of DIEs, terminated by an empty
DIE. Any children of the skipped DIEs will also be skipped. */
const gdb_byte *
cutu_reader::skip_children (const gdb_byte *info_ptr)
{
while (1)
{
unsigned int bytes_read;
const abbrev_info *abbrev = this->peek_die_abbrev (info_ptr, &bytes_read);
if (abbrev == NULL)
return info_ptr + bytes_read;
else
info_ptr = this->skip_one_die (info_ptr + bytes_read, abbrev);
}
}
/* See read.h. */
const gdb_byte *
cutu_reader::skip_one_attribute (dwarf_form form, const gdb_byte *info_ptr)
{
unsigned int bytes_read;
switch (form)
{
case DW_FORM_ref_addr:
/* In DWARF 2, DW_FORM_ref_addr is address sized; in DWARF 3
and later it is offset sized. */
if (m_cu->header.version == 2)
return info_ptr + m_cu->header.addr_size;
else
return info_ptr + m_cu->header.offset_size;
case DW_FORM_GNU_ref_alt:
return info_ptr + m_cu->header.offset_size;
case DW_FORM_addr:
return info_ptr + m_cu->header.addr_size;
case DW_FORM_data1:
case DW_FORM_ref1:
case DW_FORM_flag:
case DW_FORM_strx1:
return info_ptr + 1;
case DW_FORM_flag_present:
case DW_FORM_implicit_const:
return info_ptr;
case DW_FORM_data2:
case DW_FORM_ref2:
case DW_FORM_strx2:
return info_ptr + 2;
case DW_FORM_strx3:
return info_ptr + 3;
case DW_FORM_data4:
case DW_FORM_ref4:
case DW_FORM_strx4:
return info_ptr + 4;
case DW_FORM_data8:
case DW_FORM_ref8:
case DW_FORM_ref_sig8:
return info_ptr + 8;
case DW_FORM_data16:
return info_ptr + 16;
case DW_FORM_string:
read_direct_string (m_abfd, info_ptr, &bytes_read);
return info_ptr + bytes_read;
case DW_FORM_sec_offset:
case DW_FORM_strp:
case DW_FORM_GNU_strp_alt:
return info_ptr + m_cu->header.offset_size;
case DW_FORM_exprloc:
case DW_FORM_block:
info_ptr += read_unsigned_leb128 (m_abfd, info_ptr, &bytes_read);
return info_ptr + bytes_read;
case DW_FORM_block1:
return info_ptr + 1 + read_1_byte (m_abfd, info_ptr);
case DW_FORM_block2:
return info_ptr + 2 + read_2_bytes (m_abfd, info_ptr);
case DW_FORM_block4:
return info_ptr + 4 + read_4_bytes (m_abfd, info_ptr);
case DW_FORM_addrx:
case DW_FORM_strx:
case DW_FORM_sdata:
case DW_FORM_udata:
case DW_FORM_ref_udata:
case DW_FORM_GNU_addr_index:
case DW_FORM_GNU_str_index:
case DW_FORM_rnglistx:
case DW_FORM_loclistx:
return safe_skip_leb128 (info_ptr, m_buffer_end);
case DW_FORM_indirect:
form = static_cast<dwarf_form> (read_unsigned_leb128 (m_abfd, info_ptr,
&bytes_read));
return this->skip_one_attribute(form, info_ptr + bytes_read);
default:
error (_ (DWARF_ERROR_PREFIX
"Cannot handle %s in DWARF reader [in module %s]"),
dwarf_form_name (form), bfd_get_filename (m_abfd));
}
}
/* Scan the debug information for CU starting at INFO_PTR in buffer BUFFER.
INFO_PTR should point just after the initial uleb128 of a DIE, and the
abbrev corresponding to that skipped uleb128 should be passed in
ABBREV.
If DO_SKIP_CHILDREN is true, or if the DIE has no children, this
returns a pointer to this DIE's sibling, skipping any children.
Otherwise, returns a pointer to the DIE's first child. */
const gdb_byte *
cutu_reader::skip_one_die (const gdb_byte *info_ptr, const abbrev_info *abbrev,
bool do_skip_children)
{
if (do_skip_children && abbrev->sibling_offset != (unsigned short) -1)
{
/* We only handle DW_FORM_ref4 here. */
const gdb_byte *sibling_data = info_ptr + abbrev->sibling_offset;
unsigned int offset = read_4_bytes (m_abfd, sibling_data);
const gdb_byte *sibling_ptr
= m_buffer + to_underlying (m_cu->header.sect_off) + offset;
if (sibling_ptr >= info_ptr && sibling_ptr < m_buffer_end)
return sibling_ptr;
/* Fall through to the slow way. */
}
else if (abbrev->size_if_constant != 0)
{
info_ptr += abbrev->size_if_constant;
if (do_skip_children && abbrev->has_children)
return this->skip_children (info_ptr);
return info_ptr;
}
for (unsigned int i = 0; i < abbrev->num_attrs; i++)
{
/* The only abbrev we care about is DW_AT_sibling. */
if (do_skip_children && abbrev->attrs[i].name == DW_AT_sibling)
{
/* Note there is no need for the extra work of
"reprocessing" here, so we pass false for that
argument. */
attribute attr;
this->read_attribute (&attr, &abbrev->attrs[i], info_ptr, false);
if (attr.form == DW_FORM_ref_addr)
complaint (_("ignoring absolute DW_AT_sibling"));
else
{
sect_offset off = attr.get_ref_die_offset ();
const gdb_byte *sibling_ptr = m_buffer + to_underlying (off);
if (sibling_ptr < info_ptr)
complaint (_("DW_AT_sibling points backwards"));
else if (sibling_ptr > m_buffer_end)
m_die_section->overflow_complaint ();
else
return sibling_ptr;
}
}
/* If it isn't DW_AT_sibling, skip this attribute. */
info_ptr = this->skip_one_attribute (abbrev->attrs[i].form, info_ptr);
}
if (do_skip_children && abbrev->has_children)
return this->skip_children (info_ptr);
else
return info_ptr;
}
/* Reading in full CUs. */
/* Add PER_CU to the queue. */
static void
queue_comp_unit (dwarf2_per_cu *per_cu, dwarf2_per_objfile *per_objfile)
{
per_cu->queued = 1;
gdb_assert (per_objfile->queue.has_value ());
per_objfile->queue->emplace (per_cu, per_objfile);
}
/* If PER_CU is not yet expanded of queued for expansion, add it to the queue.
If DEPENDENT_CU is non-NULL, it has a reference to PER_CU so add a
dependency.
Return true if maybe_queue_comp_unit requires the caller to load the CU's
DIEs, false otherwise.
Explanation: there is an invariant that if a CU is queued for expansion
(present in `dwarf2_per_bfd::queue`), then its DIEs are loaded
(a dwarf2_cu object exists for this CU, and `dwarf2_per_objfile::get_cu`
returns non-nullptr). If the CU gets enqueued by this function but its DIEs
are not yet loaded, the the caller must load the CU's DIEs to ensure the
invariant is respected.
The caller is therefore not required to load the CU's DIEs (we return false)
if:
- the CU is already expanded, and therefore does not get enqueued
- the CU gets enqueued for expansion, but its DIEs are already loaded
Note that the caller should not use this function's return value as an
indicator of whether the CU's DIEs are loaded right now, it should check
that by calling `dwarf2_per_objfile::get_cu` instead. */
static bool
maybe_queue_comp_unit (struct dwarf2_cu *dependent_cu, dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile)
{
/* Mark the dependence relation so that we don't flush PER_CU
too early. */
if (dependent_cu != NULL)
dependent_cu->add_dependence (per_cu);
/* If it's already on the queue, we have nothing to do. */
if (per_cu->queued)
{
/* Verify the invariant that if a CU is queued for expansion, its DIEs are
loaded. */
gdb_assert (per_objfile->get_cu (per_cu) != nullptr);
/* If the CU is queued for expansion, it should not already be
expanded. */
gdb_assert (!per_objfile->symtab_set_p (per_cu));
/* The DIEs are already loaded, the caller doesn't need to do it. */
return false;
}
bool queued = false;
if (!per_objfile->symtab_set_p (per_cu))
{
/* Add it to the queue. */
queue_comp_unit (per_cu, per_objfile);
queued = true;
dwarf_read_debug_printf ("Queuing CU for expansion: "
"section offset = 0x%" PRIx64 ", "
"queue size = %zu",
to_underlying (per_cu->sect_off),
per_objfile->queue->size ());
}
/* If the compilation unit is already loaded, just mark it as
used. */
dwarf2_cu *cu = per_objfile->get_cu (per_cu);
if (cu != nullptr)
cu->last_used = 0;
/* Ask the caller to load the CU's DIEs if the CU got enqueued for expansion
and the DIEs are not already loaded. */
return queued && cu == nullptr;
}
/* Process the queue. */
static void
process_queue (dwarf2_per_objfile *per_objfile)
{
DWARF_READ_SCOPED_DEBUG_START_END
("Expanding one or more symtabs of objfile %s ...",
objfile_name (per_objfile->objfile));
unsigned int expanded_count = 0;
/* The queue starts out with one item, but following a DIE reference
may load a new CU, adding it to the end of the queue. */
while (!per_objfile->queue->empty ())
{
dwarf2_queue_item &item = per_objfile->queue->front ();
dwarf2_per_cu *per_cu = item.per_cu;
if (!per_objfile->symtab_set_p (per_cu))
{
dwarf2_cu *cu = per_objfile->get_cu (per_cu);
/* Skip dummy CUs. */
if (cu != nullptr)
{
namespace chr = std::chrono;
unsigned int debug_print_threshold;
char buf[100];
std::optional<chr::time_point<chr::steady_clock>> start_time;
if (per_cu->is_debug_types)
{
struct signatured_type *sig_type =
(struct signatured_type *) per_cu;
sprintf (buf, "TU %s at offset %s",
hex_string (sig_type->signature),
sect_offset_str (per_cu->sect_off));
/* There can be 100s of TUs.
Only print them in verbose mode. */
debug_print_threshold = 2;
}
else
{
sprintf (buf, "CU at offset %s",
sect_offset_str (per_cu->sect_off));
debug_print_threshold = 1;
}
if (dwarf_read_debug >= debug_print_threshold)
{
dwarf_read_debug_printf ("Expanding symtab of %s", buf);
start_time = chr::steady_clock::now ();
}
++expanded_count;
if (per_cu->is_debug_types)
process_full_type_unit (cu);
else
process_full_comp_unit (cu);
if (dwarf_read_debug >= debug_print_threshold)
{
const auto end_time = chr::steady_clock::now ();
const auto time_spent = end_time - *start_time;
const auto ms
= chr::duration_cast<chr::milliseconds> (time_spent);
dwarf_read_debug_printf ("Done expanding %s, took %.3fs", buf,
ms.count () / 1000.0);
}
}
}
per_cu->queued = 0;
per_objfile->queue->pop ();
}
dwarf_read_debug_printf ("Done expanding %u symtabs.", expanded_count);
}
/* Load the DIEs associated with PER_CU into memory. */
static void
load_full_comp_unit (dwarf2_per_cu *this_cu, dwarf2_per_objfile *per_objfile,
bool skip_partial, enum language pretend_language)
{
gdb_assert (! this_cu->is_debug_types);
gdb_assert (per_objfile->get_cu (this_cu) == nullptr);
cutu_reader reader (this_cu, per_objfile, nullptr, nullptr, skip_partial,
pretend_language);
if (reader.is_dummy ())
return;
reader.read_all_dies ();
/* Save this dwarf2_cu in the per_objfile. The per_objfile owns it
now. */
per_objfile->set_cu (this_cu, reader.release_cu ());
}
/* Add a DIE to the delayed physname list. */
static void
add_to_method_list (struct type *type, int fnfield_index, int index,
const char *name, struct die_info *die,
struct dwarf2_cu *cu)
{
struct delayed_method_info mi;
mi.type = type;
mi.fnfield_index = fnfield_index;
mi.index = index;
mi.name = name;
mi.die = die;
cu->method_list.push_back (mi);
}
/* Check whether [PHYSNAME, PHYSNAME+LEN) ends with a modifier like
"const" / "volatile". If so, decrements LEN by the length of the
modifier and return true. Otherwise return false. */
template<size_t N>
static bool
check_modifier (const char *physname, size_t &len, const char (&mod)[N])
{
size_t mod_len = sizeof (mod) - 1;
if (len > mod_len && startswith (physname + (len - mod_len), mod))
{
len -= mod_len;
return true;
}
return false;
}
/* Compute the physnames of any methods on the CU's method list.
The computation of method physnames is delayed in order to avoid the
(bad) condition that one of the method's formal parameters is of an as yet
incomplete type. */
static void
compute_delayed_physnames (struct dwarf2_cu *cu)
{
/* Only C++ delays computing physnames. */
if (cu->method_list.empty ())
return;
gdb_assert (cu->lang () == language_cplus);
for (const delayed_method_info &mi : cu->method_list)
{
const char *physname;
struct fn_fieldlist *fn_flp
= &TYPE_FN_FIELDLIST (mi.type, mi.fnfield_index);
physname = dwarf2_physname (mi.name, mi.die, cu);
TYPE_FN_FIELD_PHYSNAME (fn_flp->fn_fields, mi.index)
= physname ? physname : "";
/* Since there's no tag to indicate whether a method is a
const/volatile overload, extract that information out of the
demangled name. */
if (physname != NULL)
{
size_t len = strlen (physname);
while (1)
{
if (physname[len - 1] == ')') /* shortcut */
break;
else if (check_modifier (physname, len, " const"))
TYPE_FN_FIELD_CONST (fn_flp->fn_fields, mi.index) = 1;
else if (check_modifier (physname, len, " volatile"))
TYPE_FN_FIELD_VOLATILE (fn_flp->fn_fields, mi.index) = 1;
else
break;
}
}
}
/* The list is no longer needed. */
cu->method_list.clear ();
}
/* Go objects should be embedded in a DW_TAG_module DIE,
and it's not clear if/how imported objects will appear.
To keep Go support simple until that's worked out,
go back through what we've read and create something usable.
We could do this while processing each DIE, and feels kinda cleaner,
but that way is more invasive.
This is to, for example, allow the user to type "p var" or "b main"
without having to specify the package name, and allow lookups
of module.object to work in contexts that use the expression
parser. */
static void
fixup_go_packaging (struct dwarf2_cu *cu)
{
gdb::unique_xmalloc_ptr<char> package_name;
struct pending *list;
int i;
for (list = *cu->get_builder ()->get_global_symbols ();
list != NULL;
list = list->next)
{
for (i = 0; i < list->nsyms; ++i)
{
struct symbol *sym = list->symbol[i];
if (sym->language () == language_go
&& sym->aclass () == LOC_BLOCK)
{
gdb::unique_xmalloc_ptr<char> this_package_name
= go_symbol_package_name (sym);
if (this_package_name == NULL)
continue;
if (package_name == NULL)
package_name = std::move (this_package_name);
else
{
struct objfile *objfile = cu->per_objfile->objfile;
if (strcmp (package_name.get (), this_package_name.get ()) != 0)
complaint (_("Symtab %s has objects from two different Go packages: %s and %s"),
(sym->symtab () != NULL
? symtab_to_filename_for_display
(sym->symtab ())
: objfile_name (objfile)),
this_package_name.get (), package_name.get ());
}
}
}
}
if (package_name != NULL)
{
struct objfile *objfile = cu->per_objfile->objfile;
const char *saved_package_name = objfile->intern (package_name.get ());
struct type *type
= type_allocator (objfile, cu->lang ()).new_type (TYPE_CODE_MODULE, 0,
saved_package_name);
struct symbol *sym;
sym = new (&objfile->objfile_obstack) symbol;
sym->set_language (language_go, &objfile->objfile_obstack);
sym->compute_and_set_names (saved_package_name, false, objfile->per_bfd);
sym->set_domain (TYPE_DOMAIN);
sym->set_aclass_index (LOC_TYPEDEF);
sym->set_type (type);
add_symbol_to_list (sym, cu->get_builder ()->get_global_symbols ());
}
}
/* Allocate a fully-qualified name consisting of the two parts on the
obstack. */
static const char *
rust_fully_qualify (struct obstack *obstack, const char *p1, const char *p2)
{
return obconcat (obstack, p1, "::", p2, (char *) NULL);
}
/* A helper that allocates a variant part to attach to a Rust enum
type. OBSTACK is where the results should be allocated. TYPE is
the type we're processing. DISCRIMINANT_INDEX is the index of the
discriminant. It must be the index of one of the fields of TYPE,
or -1 to mean there is no discriminant (univariant enum).
DEFAULT_INDEX is the index of the default field; or -1 if there is
no default. RANGES is indexed by "effective" field number (the
field index, but omitting the discriminant and default fields) and
must hold the discriminant values used by the variants. Note that
RANGES must have a lifetime at least as long as OBSTACK -- either
already allocated on it, or static. */
static void
alloc_rust_variant (struct obstack *obstack, struct type *type,
int discriminant_index, int default_index,
gdb::array_view<discriminant_range> ranges)
{
/* When DISCRIMINANT_INDEX == -1, we have a univariant enum. */
gdb_assert (discriminant_index == -1
|| (discriminant_index >= 0
&& discriminant_index < type->num_fields ()));
gdb_assert (default_index == -1
|| (default_index >= 0 && default_index < type->num_fields ()));
/* We have one variant for each non-discriminant field. */
int n_variants = type->num_fields ();
if (discriminant_index != -1)
--n_variants;
variant *variants = new (obstack) variant[n_variants];
int var_idx = 0;
int range_idx = 0;
for (int i = 0; i < type->num_fields (); ++i)
{
if (i == discriminant_index)
continue;
variants[var_idx].first_field = i;
variants[var_idx].last_field = i + 1;
/* The default field does not need a range, but other fields do.
We skipped the discriminant above. */
if (i != default_index)
{
variants[var_idx].discriminants = ranges.slice (range_idx, 1);
++range_idx;
}
++var_idx;
}
gdb_assert (range_idx == ranges.size ());
gdb_assert (var_idx == n_variants);
variant_part *part = new (obstack) variant_part;
part->discriminant_index = discriminant_index;
/* If there is no discriminant, then whether it is signed is of no
consequence. */
part->is_unsigned
= (discriminant_index == -1
? false
: type->field (discriminant_index).type ()->is_unsigned ());
part->variants = gdb::array_view<variant> (variants, n_variants);
void *storage = obstack_alloc (obstack, sizeof (gdb::array_view<variant_part>));
gdb::array_view<variant_part> *prop_value
= new (storage) gdb::array_view<variant_part> (part, 1);
struct dynamic_prop prop;
prop.set_variant_parts (prop_value);
type->add_dyn_prop (DYN_PROP_VARIANT_PARTS, prop);
}
/* Some versions of rustc emitted enums in an unusual way.
Ordinary enums were emitted as unions. The first element of each
structure in the union was named "RUST$ENUM$DISR". This element
held the discriminant.
These versions of Rust also implemented the "non-zero"
optimization. When the enum had two values, and one is empty and
the other holds a pointer that cannot be zero, the pointer is used
as the discriminant, with a zero value meaning the empty variant.
Here, the union's first member is of the form
RUST$ENCODED$ENUM$<fieldno>$<fieldno>$...$<variantname>
where the fieldnos are the indices of the fields that should be
traversed in order to find the field (which may be several fields deep)
and the variantname is the name of the variant of the case when the
field is zero.
This function recognizes whether TYPE is of one of these forms,
and, if so, smashes it to be a variant type. */
static void
quirk_rust_enum (struct type *type, struct objfile *objfile)
{
gdb_assert (type->code () == TYPE_CODE_UNION);
/* We don't need to deal with empty enums. */
if (type->num_fields () == 0)
return;
#define RUST_ENUM_PREFIX "RUST$ENCODED$ENUM$"
if (type->num_fields () == 1
&& startswith (type->field (0).name (), RUST_ENUM_PREFIX))
{
const char *name = type->field (0).name () + strlen (RUST_ENUM_PREFIX);
/* Decode the field name to find the offset of the
discriminant. */
ULONGEST bit_offset = 0;
struct type *field_type = type->field (0).type ();
while (name[0] >= '0' && name[0] <= '9')
{
char *tail;
unsigned long index = strtoul (name, &tail, 10);
name = tail;
if (*name != '$'
|| index >= field_type->num_fields ()
|| (field_type->field (index).loc_kind ()
!= FIELD_LOC_KIND_BITPOS))
{
complaint (_("Could not parse Rust enum encoding string \"%s\""
"[in module %s]"),
type->field (0).name (),
objfile_name (objfile));
return;
}
++name;
bit_offset += field_type->field (index).loc_bitpos ();
field_type = field_type->field (index).type ();
}
/* Smash this type to be a structure type. We have to do this
because the type has already been recorded. */
type->set_code (TYPE_CODE_STRUCT);
/* Save the field we care about. */
struct field saved_field = type->field (0);
type->alloc_fields (3);
/* Put the discriminant at index 0. */
type->field (0).set_type (field_type);
type->field (0).set_is_artificial (true);
type->field (0).set_name ("<<discriminant>>");
type->field (0).set_loc_bitpos (bit_offset);
/* The order of fields doesn't really matter, so put the real
field at index 1 and the data-less field at index 2. */
type->field (1) = saved_field;
type->field (1).set_name
(rust_last_path_segment (type->field (1).type ()->name ()));
type->field (1).type ()->set_name
(rust_fully_qualify (&objfile->objfile_obstack, type->name (),
type->field (1).name ()));
const char *dataless_name
= rust_fully_qualify (&objfile->objfile_obstack, type->name (),
name);
struct type *dataless_type
= type_allocator (type).new_type (TYPE_CODE_VOID, 0,
dataless_name);
type->field (2).set_type (dataless_type);
/* NAME points into the original discriminant name, which
already has the correct lifetime. */
type->field (2).set_name (name);
type->field (2).set_loc_bitpos (0);
/* Indicate that this is a variant type. */
static discriminant_range ranges[1] = { { 0, 0 } };
alloc_rust_variant (&objfile->objfile_obstack, type, 0, 1, ranges);
}
/* A union with a single anonymous field is probably an old-style
univariant enum. */
else if (type->num_fields () == 1 && streq (type->field (0).name (), ""))
{
/* Smash this type to be a structure type. We have to do this
because the type has already been recorded. */
type->set_code (TYPE_CODE_STRUCT);
struct type *field_type = type->field (0).type ();
const char *variant_name
= rust_last_path_segment (field_type->name ());
type->field (0).set_name (variant_name);
field_type->set_name
(rust_fully_qualify (&objfile->objfile_obstack,
type->name (), variant_name));
alloc_rust_variant (&objfile->objfile_obstack, type, -1, 0, {});
}
else
{
struct type *disr_type = nullptr;
for (int i = 0; i < type->num_fields (); ++i)
{
disr_type = type->field (i).type ();
if (disr_type->code () != TYPE_CODE_STRUCT)
{
/* All fields of a true enum will be structs. */
return;
}
else if (disr_type->num_fields () == 0)
{
/* Could be data-less variant, so keep going. */
disr_type = nullptr;
}
else if (strcmp (disr_type->field (0).name (),
"RUST$ENUM$DISR") != 0)
{
/* Not a Rust enum. */
return;
}
else
{
/* Found one. */
break;
}
}
/* If we got here without a discriminant, then it's probably
just a union. */
if (disr_type == nullptr)
return;
/* Smash this type to be a structure type. We have to do this
because the type has already been recorded. */
type->set_code (TYPE_CODE_STRUCT);
/* Make space for the discriminant field. */
struct field *disr_field = &disr_type->field (0);
field *new_fields
= (struct field *) TYPE_ZALLOC (type, ((type->num_fields () + 1)
* sizeof (struct field)));
memcpy (new_fields + 1, type->fields (),
type->num_fields () * sizeof (struct field));
type->set_fields (new_fields);
type->set_num_fields (type->num_fields () + 1);
/* Install the discriminant at index 0 in the union. */
type->field (0) = *disr_field;
type->field (0).set_is_artificial (true);
type->field (0).set_name ("<<discriminant>>");
/* We need a way to find the correct discriminant given a
variant name. For convenience we build a map here. */
struct type *enum_type = disr_field->type ();
gdb::unordered_map<std::string_view, ULONGEST> discriminant_map;
for (int i = 0; i < enum_type->num_fields (); ++i)
{
if (enum_type->field (i).loc_kind () == FIELD_LOC_KIND_ENUMVAL)
{
const char *name
= rust_last_path_segment (enum_type->field (i).name ());
discriminant_map[name] = enum_type->field (i).loc_enumval ();
}
}
int n_fields = type->num_fields ();
/* We don't need a range entry for the discriminant, but we do
need one for every other field, as there is no default
variant. */
discriminant_range *ranges = XOBNEWVEC (&objfile->objfile_obstack,
discriminant_range,
n_fields - 1);
/* Skip the discriminant here. */
for (int i = 1; i < n_fields; ++i)
{
/* Find the final word in the name of this variant's type.
That name can be used to look up the correct
discriminant. */
const char *variant_name
= rust_last_path_segment (type->field (i).type ()->name ());
auto iter = discriminant_map.find (variant_name);
if (iter != discriminant_map.end ())
{
ranges[i - 1].low = iter->second;
ranges[i - 1].high = iter->second;
}
/* In Rust, each element should have the size of the
enclosing enum. */
type->field (i).type ()->set_length (type->length ());
/* Remove the discriminant field, if it exists. */
struct type *sub_type = type->field (i).type ();
if (sub_type->num_fields () > 0)
{
sub_type->set_num_fields (sub_type->num_fields () - 1);
sub_type->set_fields (sub_type->fields () + 1);
}
type->field (i).set_name (variant_name);
sub_type->set_name
(rust_fully_qualify (&objfile->objfile_obstack,
type->name (), variant_name));
}
/* Indicate that this is a variant type. */
alloc_rust_variant (&objfile->objfile_obstack, type, 0, -1,
gdb::array_view<discriminant_range> (ranges,
n_fields - 1));
}
}
/* Rewrite some Rust unions to be structures with variants parts. */
static void
rust_union_quirks (struct dwarf2_cu *cu)
{
gdb_assert (cu->lang () == language_rust);
for (type *type_ : cu->rust_unions)
quirk_rust_enum (type_, cu->per_objfile->objfile);
/* We don't need this any more. */
cu->rust_unions.clear ();
}
/* See read.h. */
type_unit_group_unshareable *
dwarf2_per_objfile::get_type_unit_group_unshareable
(stmt_list_hash tu_group_key)
{
auto [it, inserted] = m_type_units.emplace (tu_group_key, nullptr);
if (inserted)
it->second = std::make_unique<type_unit_group_unshareable> ();
return it->second.get ();
}
struct type *
dwarf2_per_objfile::get_type_for_signatured_type
(signatured_type *sig_type) const
{
auto iter = m_type_map.find (sig_type);
if (iter == m_type_map.end ())
return nullptr;
return iter->second;
}
void dwarf2_per_objfile::set_type_for_signatured_type
(signatured_type *sig_type, struct type *type)
{
gdb_assert (m_type_map.find (sig_type) == m_type_map.end ());
m_type_map[sig_type] = type;
}
/* A helper function for computing the list of all symbol tables
included by PER_CU. */
static void
recursively_compute_inclusions
(std::vector<compunit_symtab *> *result,
gdb::unordered_set<dwarf2_per_cu *> &all_children,
gdb::unordered_set<compunit_symtab *> &all_type_symtabs,
dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile,
struct compunit_symtab *immediate_parent)
{
if (bool inserted = all_children.emplace (per_cu).second;
!inserted)
{
/* This inclusion and its children have been processed. */
return;
}
/* Only add a CU if it has a symbol table. */
compunit_symtab *cust = per_objfile->get_symtab (per_cu);
if (cust != NULL)
{
/* If this is a type unit only add its symbol table if we haven't
seen it yet (type unit per_cu's can share symtabs). */
if (per_cu->is_debug_types)
{
if (bool inserted = all_type_symtabs.insert (cust).second;
inserted)
{
result->push_back (cust);
if (cust->user == NULL)
cust->user = immediate_parent;
}
}
else
{
result->push_back (cust);
if (cust->user == NULL)
cust->user = immediate_parent;
}
}
for (dwarf2_per_cu *ptr : per_cu->imported_symtabs)
recursively_compute_inclusions (result, all_children,
all_type_symtabs, ptr, per_objfile,
cust);
}
/* Compute the compunit_symtab 'includes' fields for the compunit_symtab of
PER_CU. */
static void
compute_compunit_symtab_includes (dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile)
{
gdb_assert (! per_cu->is_debug_types);
if (!per_cu->imported_symtabs.empty ())
{
int len;
std::vector<compunit_symtab *> result_symtabs;
compunit_symtab *cust = per_objfile->get_symtab (per_cu);
/* If we don't have a symtab, we can just skip this case. */
if (cust == NULL)
return;
gdb::unordered_set<dwarf2_per_cu *> all_children;
gdb::unordered_set<compunit_symtab *> all_type_symtabs;
for (dwarf2_per_cu *ptr : per_cu->imported_symtabs)
recursively_compute_inclusions (&result_symtabs, all_children,
all_type_symtabs, ptr,
per_objfile, cust);
/* Now we have a transitive closure of all the included symtabs. */
len = result_symtabs.size ();
cust->includes
= XOBNEWVEC (&per_objfile->objfile->objfile_obstack,
struct compunit_symtab *, len + 1);
memcpy (cust->includes, result_symtabs.data (),
len * sizeof (compunit_symtab *));
cust->includes[len] = NULL;
}
}
/* Compute the 'includes' field for the symtabs of all the CUs we just
read. */
static void
process_cu_includes (dwarf2_per_objfile *per_objfile)
{
for (dwarf2_per_cu *iter : per_objfile->per_bfd->just_read_cus)
{
if (! iter->is_debug_types)
compute_compunit_symtab_includes (iter, per_objfile);
}
per_objfile->per_bfd->just_read_cus.clear ();
}
/* Generate full symbol information for CU, whose DIEs have
already been loaded into memory. */
static void
process_full_comp_unit (dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
unrelocated_addr lowpc, highpc;
struct compunit_symtab *cust;
struct block *static_block;
CORE_ADDR addr;
/* Clear the list here in case something was left over. */
cu->method_list.clear ();
dwarf2_find_base_address (cu->dies, cu);
/* Before we start reading the top-level DIE, ensure it has a valid tag
type. */
switch (cu->dies->tag)
{
case DW_TAG_compile_unit:
case DW_TAG_partial_unit:
case DW_TAG_type_unit:
break;
default:
error (_(DWARF_ERROR_PREFIX
"unexpected tag '%s' at offset %s [in module %s]"),
dwarf_tag_name (cu->dies->tag),
sect_offset_str (cu->per_cu->sect_off),
objfile_name (per_objfile->objfile));
}
/* Do line number decoding in read_file_scope () */
process_die (cu->dies, cu);
/* For now fudge the Go package. */
if (cu->lang () == language_go)
fixup_go_packaging (cu);
/* Now that we have processed all the DIEs in the CU, all the types
should be complete, and it should now be safe to compute all of the
physnames. */
compute_delayed_physnames (cu);
if (cu->lang () == language_rust)
rust_union_quirks (cu);
/* Some compilers don't define a DW_AT_high_pc attribute for the
compilation unit. If the DW_AT_high_pc is missing, synthesize
it, by scanning the DIE's below the compilation unit. */
get_scope_pc_bounds (cu->dies, &lowpc, &highpc, cu);
addr = per_objfile->relocate (highpc);
static_block
= cu->get_builder ()->end_compunit_symtab_get_static_block (addr, 0, 1);
/* If the comp unit has DW_AT_ranges, it may have discontiguous ranges.
Also, DW_AT_ranges may record ranges not belonging to any child DIEs
(such as virtual method tables). Record the ranges in STATIC_BLOCK's
addrmap to help ensure it has an accurate map of pc values belonging to
this comp unit. */
dwarf2_record_block_ranges (cu->dies, static_block, cu);
cust = cu->get_builder ()->end_compunit_symtab_from_static_block
(static_block, 0);
if (cust != NULL)
{
/* Set symtab language to language from DW_AT_language. If the
compilation is from a C file generated by language preprocessors, do
not set the language if it was already deduced by start_subfile. */
if (!(cu->lang () == language_c
&& cust->primary_filetab ()->language () != language_unknown))
cust->primary_filetab ()->set_language (cu->lang ());
/* GCC-4.0 has started to support -fvar-tracking. GCC-3.x still can
produce DW_AT_location with location lists but it can be possibly
invalid without -fvar-tracking. Still up to GCC-4.4.x incl. 4.4.0
there were bugs in prologue debug info, fixed later in GCC-4.5
by "unwind info for epilogues" patch (which is not directly related).
For -gdwarf-4 type units LOCATIONS_VALID indication is fortunately not
needed, it would be wrong due to missing DW_AT_producer there.
Still one can confuse GDB by using non-standard GCC compilation
options - this waits on GCC PR other/32998 (-frecord-gcc-switches).
*/
/* Note that this code traditionally did not accept non-GCC
compilers; that is preserved but seems potentially wrong. */
if (cu->has_loclist && cu->producer_is_gcc ()
&& !cu->producer_is_gcc_lt_4_5 ())
cust->set_locations_valid (true);
if (cu->producer_is_gcc_lt_4_5 ())
/* Don't trust gcc < 4.5.x. */
cust->set_epilogue_unwind_valid (false);
else
cust->set_epilogue_unwind_valid (true);
cust->set_call_site_htab (std::move (cu->call_site_htab));
}
per_objfile->set_symtab (cu->per_cu, cust);
/* Push it for inclusion processing later. */
per_objfile->per_bfd->just_read_cus.push_back (cu->per_cu);
/* Not needed any more. */
cu->reset_builder ();
}
/* Generate full symbol information for type unit CU, whose DIEs have
already been loaded into memory. */
static void
process_full_type_unit (dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct compunit_symtab *cust;
struct signatured_type *sig_type;
gdb_assert (cu->per_cu->is_debug_types);
sig_type = (struct signatured_type *) cu->per_cu;
/* Clear the list here in case something was left over. */
cu->method_list.clear ();
/* The symbol tables are set up in read_type_unit_scope. */
process_die (cu->dies, cu);
/* For now fudge the Go package. */
if (cu->lang () == language_go)
fixup_go_packaging (cu);
/* Now that we have processed all the DIEs in the CU, all the types
should be complete, and it should now be safe to compute all of the
physnames. */
compute_delayed_physnames (cu);
if (cu->lang () == language_rust)
rust_union_quirks (cu);
/* TUs share symbol tables.
If this is the first TU to use this symtab, complete the construction
of it with end_expandable_symtab. Otherwise, complete the addition of
this TU's symbols to the existing symtab. */
type_unit_group_unshareable *tug_unshare =
per_objfile->get_type_unit_group_unshareable (*sig_type->type_unit_group_key);
if (tug_unshare->compunit_symtab == NULL)
{
buildsym_compunit *builder = cu->get_builder ();
cust = builder->end_expandable_symtab (0);
tug_unshare->compunit_symtab = cust;
if (cust != NULL)
{
/* Set symtab language to language from DW_AT_language. If the
compilation is from a C file generated by language preprocessors,
do not set the language if it was already deduced by
start_subfile. */
if (!(cu->lang () == language_c
&& cust->primary_filetab ()->language () != language_c))
cust->primary_filetab ()->set_language (cu->lang ());
}
}
else
{
cu->get_builder ()->augment_type_symtab ();
cust = tug_unshare->compunit_symtab;
}
per_objfile->set_symtab (cu->per_cu, cust);
/* Not needed any more. */
cu->reset_builder ();
}
/* Process an imported unit DIE. */
static void
process_imported_unit_die (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr;
/* For now we don't handle imported units in type units. */
if (cu->per_cu->is_debug_types)
{
error (_(DWARF_ERROR_PREFIX
"DW_TAG_imported_unit is not supported in type units"
" [in module %s]"),
objfile_name (cu->per_objfile->objfile));
}
attr = dwarf2_attr (die, DW_AT_import, cu);
if (attr != NULL)
{
sect_offset sect_off = attr->get_ref_die_offset ();
bool is_dwz = (attr->form == DW_FORM_GNU_ref_alt || cu->per_cu->is_dwz);
dwarf2_per_objfile *per_objfile = cu->per_objfile;
dwarf2_per_cu *per_cu
= dwarf2_find_containing_comp_unit (sect_off, is_dwz,
per_objfile->per_bfd);
/* We're importing a C++ compilation unit with tag DW_TAG_compile_unit
into another compilation unit, at root level. Regard this as a hint,
and ignore it. This is a best effort, it only works if unit_type and
lang are already set. */
if (die->parent && die->parent->parent == NULL
&& per_cu->unit_type (false) == DW_UT_compile
&& per_cu->lang (false) == language_cplus)
return;
/* If necessary, add it to the queue and load its DIEs. */
if (maybe_queue_comp_unit (cu, per_cu, per_objfile))
load_full_comp_unit (per_cu, per_objfile, false, cu->lang ());
cu->per_cu->imported_symtabs.push_back (per_cu);
}
}
/* RAII object that represents a process_die scope: i.e.,
starts/finishes processing a DIE. */
class process_die_scope
{
public:
process_die_scope (die_info *die, dwarf2_cu *cu)
: m_die (die), m_cu (cu)
{
/* We should only be processing DIEs not already in process. */
gdb_assert (!m_die->in_process);
m_die->in_process = true;
}
~process_die_scope ()
{
m_die->in_process = false;
/* If we're done processing the DIE for the CU that owns the line
header, we don't need the line header anymore. */
if (m_cu->line_header_die_owner == m_die)
{
delete m_cu->line_header;
m_cu->line_header = NULL;
m_cu->line_header_die_owner = NULL;
}
}
private:
die_info *m_die;
dwarf2_cu *m_cu;
};
/* Process a die and its children. */
static void
process_die (struct die_info *die, struct dwarf2_cu *cu)
{
process_die_scope scope (die, cu);
switch (die->tag)
{
case DW_TAG_padding:
break;
case DW_TAG_compile_unit:
case DW_TAG_partial_unit:
read_file_scope (die, cu);
break;
case DW_TAG_type_unit:
read_type_unit_scope (die, cu);
break;
case DW_TAG_subprogram:
/* Nested subprograms in Fortran get a prefix. */
if (cu->lang () == language_fortran
&& die->parent != NULL
&& die->parent->tag == DW_TAG_subprogram)
cu->processing_has_namespace_info = true;
[[fallthrough]];
/* Fall through. */
case DW_TAG_entry_point:
case DW_TAG_inlined_subroutine:
read_func_scope (die, cu);
break;
case DW_TAG_lexical_block:
case DW_TAG_try_block:
case DW_TAG_catch_block:
read_lexical_block_scope (die, cu);
break;
case DW_TAG_call_site:
case DW_TAG_GNU_call_site:
read_call_site_scope (die, cu);
break;
case DW_TAG_class_type:
case DW_TAG_interface_type:
case DW_TAG_structure_type:
case DW_TAG_union_type:
case DW_TAG_namelist:
process_structure_scope (die, cu);
break;
case DW_TAG_enumeration_type:
process_enumeration_scope (die, cu);
break;
/* These dies have a type, but processing them does not create
a symbol or recurse to process the children. Therefore we can
read them on-demand through read_type_die. */
case DW_TAG_subroutine_type:
case DW_TAG_set_type:
case DW_TAG_pointer_type:
case DW_TAG_ptr_to_member_type:
case DW_TAG_reference_type:
case DW_TAG_rvalue_reference_type:
case DW_TAG_string_type:
break;
case DW_TAG_array_type:
/* We only need to handle this case for Ada -- in other
languages, it's normal for the compiler to emit a typedef
instead. */
if (cu->lang () != language_ada)
break;
[[fallthrough]];
case DW_TAG_base_type:
case DW_TAG_subrange_type:
case DW_TAG_generic_subrange:
case DW_TAG_typedef:
case DW_TAG_unspecified_type:
/* Add a typedef symbol for the type definition, if it has a
DW_AT_name. */
new_symbol (die, read_type_die (die, cu), cu);
break;
case DW_TAG_common_block:
read_common_block (die, cu);
break;
case DW_TAG_common_inclusion:
break;
case DW_TAG_namespace:
cu->processing_has_namespace_info = true;
read_namespace (die, cu);
break;
case DW_TAG_module:
cu->processing_has_namespace_info = true;
read_module (die, cu);
break;
case DW_TAG_imported_declaration:
cu->processing_has_namespace_info = true;
if (read_alias (die, cu))
break;
/* The declaration is neither a global namespace nor a variable
alias. */
[[fallthrough]];
case DW_TAG_imported_module:
cu->processing_has_namespace_info = true;
if (die->child != NULL && (die->tag == DW_TAG_imported_declaration
|| cu->lang () != language_fortran))
complaint (_("Tag '%s' has unexpected children"),
dwarf_tag_name (die->tag));
read_import_statement (die, cu);
break;
case DW_TAG_imported_unit:
process_imported_unit_die (die, cu);
break;
case DW_TAG_variable:
read_variable (die, cu);
break;
default:
new_symbol (die, NULL, cu);
break;
}
}
/* DWARF name computation. */
/* A helper function for dwarf2_compute_name which determines whether DIE
needs to have the name of the scope prepended to the name listed in the
die. */
static int
die_needs_namespace (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr;
if (tag_is_type (die->tag) && die->tag != DW_TAG_template_type_param)
{
/* Historically GNAT emitted some types in funny scopes. For
example, in one test case, where the first use of Natural was
as the type of a field in a record, GNAT emitted:
<2>: DW_TAG_structure_type
... variant parts and whatnot
<5>: DW_TAG_subrange_type
. DW_AT_name: natural
To detect this, we look up the DIE tree for a node that has
a name; and if that name is fully qualified, we return 0
here. */
if (cu->lang () == language_ada)
{
for (die_info *iter = die->parent;
iter != nullptr;
iter = iter->parent)
{
if (tag_is_type (iter->tag))
{
const char *name = dwarf2_name (iter, cu);
if (name != nullptr)
return strstr (name, "__") == nullptr;
}
}
}
return 1;
}
switch (die->tag)
{
case DW_TAG_enumerator:
case DW_TAG_subprogram:
case DW_TAG_inlined_subroutine:
case DW_TAG_entry_point:
case DW_TAG_member:
case DW_TAG_imported_declaration:
return 1;
case DW_TAG_module:
/* We don't need the namespace for Fortran modules, but we do
for Ada packages. */
return cu->lang () == language_ada;
case DW_TAG_variable:
case DW_TAG_constant:
/* We only need to prefix "globally" visible variables. These include
any variable marked with DW_AT_external or any variable that
lives in a namespace. [Variables in anonymous namespaces
require prefixing, but they are not DW_AT_external.] */
if (dwarf2_attr (die, DW_AT_specification, cu))
{
struct dwarf2_cu *spec_cu = cu;
return die_needs_namespace (die_specification (die, &spec_cu),
spec_cu);
}
attr = dwarf2_attr (die, DW_AT_external, cu);
if (attr == NULL && die->parent->tag != DW_TAG_namespace
&& die->parent->tag != DW_TAG_module)
return 0;
/* A variable in a lexical block of some kind does not need a
namespace, even though in C++ such variables may be external
and have a mangled name. */
if (die->parent->tag == DW_TAG_lexical_block
|| die->parent->tag == DW_TAG_try_block
|| die->parent->tag == DW_TAG_catch_block
|| die->parent->tag == DW_TAG_subprogram)
return 0;
return 1;
default:
return 0;
}
}
/* Return the DIE's linkage name attribute, either DW_AT_linkage_name
or DW_AT_MIPS_linkage_name. Returns NULL if the attribute is not
defined for the given DIE. */
static struct attribute *
dw2_linkage_name_attr (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr;
attr = dwarf2_attr (die, DW_AT_linkage_name, cu);
if (attr == NULL)
attr = dwarf2_attr (die, DW_AT_MIPS_linkage_name, cu);
return attr;
}
/* Return the DIE's linkage name as a string, either DW_AT_linkage_name
or DW_AT_MIPS_linkage_name. Returns NULL if the attribute is not
defined for the given DIE. */
static const char *
dw2_linkage_name (struct die_info *die, struct dwarf2_cu *cu)
{
const char *linkage_name;
linkage_name = dwarf2_string_attr (die, DW_AT_linkage_name, cu);
if (linkage_name == NULL)
linkage_name = dwarf2_string_attr (die, DW_AT_MIPS_linkage_name, cu);
/* rustc emits invalid values for DW_AT_linkage_name. Ignore these.
See https://github.com/rust-lang/rust/issues/32925. */
if (cu->lang () == language_rust && linkage_name != NULL
&& strchr (linkage_name, '{') != NULL)
linkage_name = NULL;
return linkage_name;
}
/* Compute the fully qualified name of DIE in CU. If PHYSNAME is nonzero,
compute the physname for the object, which include a method's:
- formal parameters (C++),
- receiver type (Go),
The term "physname" is a bit confusing.
For C++, for example, it is the demangled name.
For Go, for example, it's the mangled name.
For Ada, return the DIE's linkage name rather than the fully qualified
name. PHYSNAME is ignored..
The result is allocated on the objfile->per_bfd's obstack and
canonicalized. */
static const char *
dwarf2_compute_name (const char *name,
struct die_info *die, struct dwarf2_cu *cu,
int physname)
{
struct objfile *objfile = cu->per_objfile->objfile;
if (name == NULL)
name = dwarf2_name (die, cu);
enum language lang = cu->lang ();
/* For Fortran GDB prefers DW_AT_*linkage_name for the physname if present
but otherwise compute it by typename_concat inside GDB.
FIXME: Actually this is not really true, or at least not always true.
It's all very confusing. compute_and_set_names doesn't try to demangle
Fortran names because there is no mangling standard. So new_symbol
will set the demangled name to the result of dwarf2_full_name, and it is
the demangled name that GDB uses if it exists. */
if ((lang == language_ada || lang == language_fortran) && physname)
{
/* For Ada unit, we prefer the linkage name over the name, as
the former contains the exported name, which the user expects
to be able to reference. Ideally, we want the user to be able
to reference this entity using either natural or linkage name,
but we haven't started looking at this enhancement yet. */
const char *linkage_name = dw2_linkage_name (die, cu);
if (linkage_name != NULL)
return linkage_name;
}
/* Some versions of GNAT emit fully-qualified names already. These
have "__" separating the components -- something ordinary names
will never have. */
if (lang == language_ada
&& name != nullptr
&& strstr (name, "__") != nullptr)
return name;
/* These are the only languages we know how to qualify names in. */
if (name != NULL
&& (lang == language_cplus
|| lang == language_fortran
|| lang == language_d
|| lang == language_rust
|| lang == language_ada))
{
if (die_needs_namespace (die, cu))
{
const char *prefix;
string_file buf;
prefix = determine_prefix (die, cu);
if (*prefix != '\0')
{
gdb::unique_xmalloc_ptr<char> prefixed_name
= typename_concat (prefix, name, physname, cu);
buf.puts (prefixed_name.get ());
}
else
buf.puts (name);
/* Template parameters may be specified in the DIE's DW_AT_name, or
as children with DW_TAG_template_type_param or
DW_TAG_value_type_param. If the latter, add them to the name
here. If the name already has template parameters, then
skip this step; some versions of GCC emit both, and
it is more efficient to use the pre-computed name.
Something to keep in mind about this process: it is very
unlikely, or in some cases downright impossible, to produce
something that will match the mangled name of a function.
If the definition of the function has the same debug info,
we should be able to match up with it anyway. But fallbacks
using the minimal symbol, for instance to find a method
implemented in a stripped copy of libstdc++, will not work.
If we do not have debug info for the definition, we will have to
match them up some other way.
When we do name matching there is a related problem with function
templates; two instantiated function templates are allowed to
differ only by their return types, which we do not add here. */
if (lang == language_cplus && strchr (name, '<') == NULL)
{
struct attribute *attr;
struct die_info *child;
int first = 1;
die->building_fullname = 1;
for (child = die->child; child != NULL; child = child->sibling)
{
struct type *type;
LONGEST value;
const gdb_byte *bytes;
struct dwarf2_locexpr_baton *baton;
struct value *v;
if (child->tag != DW_TAG_template_type_param
&& child->tag != DW_TAG_template_value_param)
continue;
if (first)
{
buf.puts ("<");
first = 0;
}
else
buf.puts (", ");
attr = dwarf2_attr (child, DW_AT_type, cu);
if (attr == NULL)
{
complaint (_("template parameter missing DW_AT_type"));
buf.puts ("UNKNOWN_TYPE");
continue;
}
type = die_type (child, cu);
if (child->tag == DW_TAG_template_type_param)
{
cu->language_defn->print_type (type, "", &buf, -1, 0,
&type_print_raw_options);
continue;
}
attr = dwarf2_attr (child, DW_AT_const_value, cu);
if (attr == NULL)
{
complaint (_("template parameter missing "
"DW_AT_const_value"));
buf.puts ("UNKNOWN_VALUE");
continue;
}
dwarf2_const_value_attr (attr, type, name,
&cu->comp_unit_obstack, cu,
&value, &bytes, &baton);
if (type->has_no_signedness ())
/* GDB prints characters as NUMBER 'CHAR'. If that's
changed, this can use value_print instead. */
cu->language_defn->printchar (value, type, &buf);
else
{
struct value_print_options opts;
if (baton != NULL)
v = dwarf2_evaluate_loc_desc (type, NULL,
baton->data,
baton->size,
baton->per_cu,
baton->per_objfile);
else if (bytes != NULL)
{
v = value::allocate (type);
memcpy (v->contents_writeable ().data (), bytes,
type->length ());
}
else
v = value_from_longest (type, value);
/* Specify decimal so that we do not depend on
the radix. */
get_formatted_print_options (&opts, 'd');
opts.raw = true;
value_print (v, &buf, &opts);
release_value (v);
}
}
die->building_fullname = 0;
if (!first)
{
/* Close the argument list, with a space if necessary
(nested templates). */
if (!buf.empty () && buf.string ().back () == '>')
buf.puts (" >");
else
buf.puts (">");
}
}
/* For C++ methods, append formal parameter type
information, if PHYSNAME. */
if (physname && die->tag == DW_TAG_subprogram
&& lang == language_cplus)
{
struct type *type = read_type_die (die, cu);
c_type_print_args (type, &buf, 1, lang,
&type_print_raw_options);
if (lang == language_cplus)
{
/* Assume that an artificial first parameter is
"this", but do not crash if it is not. RealView
marks unnamed (and thus unused) parameters as
artificial; there is no way to differentiate
the two cases. */
if (type->num_fields () > 0
&& type->field (0).is_artificial ()
&& type->field (0).type ()->code () == TYPE_CODE_PTR
&& TYPE_CONST (type->field (0).type ()->target_type ()))
buf.puts (" const");
}
}
const std::string &intermediate_name = buf.string ();
const char *canonical_name
= dwarf2_canonicalize_name (intermediate_name.c_str (), cu,
objfile);
/* If we only computed INTERMEDIATE_NAME, or if
INTERMEDIATE_NAME is already canonical, then we need to
intern it. */
if (canonical_name == NULL || canonical_name == intermediate_name.c_str ())
name = objfile->intern (intermediate_name);
else
name = canonical_name;
}
}
return name;
}
/* Return the fully qualified name of DIE, based on its DW_AT_name.
If scope qualifiers are appropriate they will be added. The result
will be allocated on the storage_obstack, or NULL if the DIE does
not have a name. NAME may either be from a previous call to
dwarf2_name or NULL.
The output string will be canonicalized (if C++). */
static const char *
dwarf2_full_name (const char *name, struct die_info *die, struct dwarf2_cu *cu)
{
return dwarf2_compute_name (name, die, cu, 0);
}
/* Construct a physname for the given DIE in CU. NAME may either be
from a previous call to dwarf2_name or NULL. The result will be
allocated on the objfile_obstack or NULL if the DIE does not have a
name.
The output string will be canonicalized (if C++). */
static const char *
dwarf2_physname (const char *name, struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
const char *retval, *mangled = NULL, *canon = NULL;
int need_copy = 1;
/* In this case dwarf2_compute_name is just a shortcut not building anything
on its own. */
if (!die_needs_namespace (die, cu))
return dwarf2_compute_name (name, die, cu, 1);
if (cu->lang () != language_rust)
mangled = dw2_linkage_name (die, cu);
/* DW_AT_linkage_name is missing in some cases - depend on what GDB
has computed. */
gdb::unique_xmalloc_ptr<char> demangled;
if (mangled != NULL)
{
if (cu->language_defn->store_sym_names_in_linkage_form_p ())
{
/* Do nothing (do not demangle the symbol name). */
}
else
{
/* Use DMGL_RET_DROP for C++ template functions to suppress
their return type. It is easier for GDB users to search
for such functions as `name(params)' than `long name(params)'.
In such case the minimal symbol names do not match the full
symbol names but for template functions there is never a need
to look up their definition from their declaration so
the only disadvantage remains the minimal symbol variant
`long name(params)' does not have the proper inferior type. */
demangled = gdb_demangle (mangled, (DMGL_PARAMS | DMGL_ANSI
| DMGL_RET_DROP));
}
if (demangled)
canon = demangled.get ();
else
{
canon = mangled;
need_copy = 0;
}
}
if (canon == NULL || check_physname)
{
const char *physname = dwarf2_compute_name (name, die, cu, 1);
if (canon != NULL && strcmp (physname, canon) != 0)
{
/* It may not mean a bug in GDB. The compiler could also
compute DW_AT_linkage_name incorrectly. But in such case
GDB would need to be bug-to-bug compatible. */
complaint (_("Computed physname <%s> does not match demangled <%s> "
"(from linkage <%s>) - DIE at %s [in module %s]"),
physname, canon, mangled, sect_offset_str (die->sect_off),
objfile_name (objfile));
/* Prefer DW_AT_linkage_name (in the CANON form) - when it
is available here - over computed PHYSNAME. It is safer
against both buggy GDB and buggy compilers. */
retval = canon;
}
else
{
retval = physname;
need_copy = 0;
}
}
else
retval = canon;
if (need_copy)
retval = objfile->intern (retval);
return retval;
}
/* Inspect DIE in CU for a namespace alias or a variable with alias
attribute. If one exists, record a new symbol for it.
Returns true if an alias was recorded, false otherwise. */
static bool
read_alias (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr;
/* If the die does not have a name, this is neither a namespace
alias nor a variable alias. */
attr = dwarf2_attr (die, DW_AT_name, cu);
if (attr != NULL)
{
int num;
struct die_info *d = die;
struct dwarf2_cu *imported_cu = cu;
/* If the compiler has nested DW_AT_imported_declaration DIEs,
keep inspecting DIEs until we hit the underlying import. */
#define MAX_NESTED_IMPORTED_DECLARATIONS 100
for (num = 0; num < MAX_NESTED_IMPORTED_DECLARATIONS; ++num)
{
attr = dwarf2_attr (d, DW_AT_import, cu);
if (attr == NULL)
break;
d = follow_die_ref (d, attr, &imported_cu);
if (d->tag != DW_TAG_imported_declaration)
break;
}
if (num == MAX_NESTED_IMPORTED_DECLARATIONS)
{
complaint (_("DIE at %s has too many recursively imported "
"declarations"), sect_offset_str (d->sect_off));
return false;
}
if (attr != NULL)
{
struct type *type;
if (d->tag == DW_TAG_variable)
{
/* This declaration is a C/C++ global variable alias.
Add a symbol for it whose type is the same as the
aliased variable's. */
type = die_type (d, imported_cu);
struct symbol *sym = new_symbol (die, type, cu);
attr = dwarf2_attr (d, DW_AT_location, imported_cu);
sym->set_aclass_index (LOC_UNRESOLVED);
if (attr != nullptr)
var_decode_location (attr, sym, cu);
return true;
}
else
{
sect_offset sect_off = attr->get_ref_die_offset ();
type = get_die_type_at_offset (sect_off, cu->per_cu,
cu->per_objfile);
if (type != nullptr && type->code () == TYPE_CODE_NAMESPACE)
{
/* This declaration is a global namespace alias. Add
a symbol for it whose type is the aliased
namespace. */
new_symbol (die, type, cu);
return true;
}
}
}
}
return false;
}
/* Return the using directives repository (global or local?) to use in the
current context for CU.
For Ada, imported declarations can materialize renamings, which *may* be
global. However it is impossible (for now?) in DWARF to distinguish
"external" imported declarations and "static" ones. As all imported
declarations seem to be static in all other languages, make them all CU-wide
global only in Ada. */
static struct using_direct **
using_directives (struct dwarf2_cu *cu)
{
if (cu->lang () == language_ada
&& cu->get_builder ()->outermost_context_p ())
return cu->get_builder ()->get_global_using_directives ();
else
return cu->get_builder ()->get_local_using_directives ();
}
/* Read the DW_ATTR_decl_line attribute for the given DIE in the
given CU. If the format is not recognized or the attribute is
not present, set it to 0. */
static unsigned int
read_decl_line (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *decl_line = dwarf2_attr (die, DW_AT_decl_line, cu);
if (decl_line == nullptr)
return 0;
std::optional<ULONGEST> val = decl_line->unsigned_constant ();
if (val.has_value ())
{
if (*val <= UINT_MAX)
return (unsigned int) *val;
complaint (_("Declared line for using directive is too large"));
}
return 0;
}
/* Read the import statement specified by the given die and record it. */
static void
read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct attribute *import_attr;
struct die_info *imported_die, *child_die;
struct dwarf2_cu *imported_cu;
const char *imported_name;
const char *imported_name_prefix;
const char *canonical_name;
const char *import_alias;
const char *imported_declaration = NULL;
const char *import_prefix;
std::vector<const char *> excludes;
import_attr = dwarf2_attr (die, DW_AT_import, cu);
if (import_attr == NULL)
{
complaint (_("Tag '%s' has no DW_AT_import"),
dwarf_tag_name (die->tag));
return;
}
imported_cu = cu;
imported_die = follow_die_ref_or_sig (die, import_attr, &imported_cu);
imported_name = dwarf2_name (imported_die, imported_cu);
if (imported_name == NULL)
{
/* GCC bug: https://bugzilla.redhat.com/show_bug.cgi?id=506524
The import in the following code:
namespace A
{
typedef int B;
}
int main ()
{
using A::B;
B b;
return b;
}
...
<2><51>: Abbrev Number: 3 (DW_TAG_imported_declaration)
<52> DW_AT_decl_file : 1
<53> DW_AT_decl_line : 6
<54> DW_AT_import : <0x75>
<2><58>: Abbrev Number: 4 (DW_TAG_typedef)
<59> DW_AT_name : B
<5b> DW_AT_decl_file : 1
<5c> DW_AT_decl_line : 2
<5d> DW_AT_type : <0x6e>
...
<1><75>: Abbrev Number: 7 (DW_TAG_base_type)
<76> DW_AT_byte_size : 4
<77> DW_AT_encoding : 5 (signed)
imports the wrong die ( 0x75 instead of 0x58 ).
This case will be ignored until the gcc bug is fixed. */
return;
}
/* Figure out the local name after import. */
import_alias = dwarf2_name (die, cu);
/* Figure out where the statement is being imported to. */
import_prefix = determine_prefix (die, cu);
/* Figure out what the scope of the imported die is and prepend it
to the name of the imported die. */
imported_name_prefix = determine_prefix (imported_die, imported_cu);
if (imported_die->tag != DW_TAG_namespace
&& imported_die->tag != DW_TAG_module)
{
imported_declaration = imported_name;
canonical_name = imported_name_prefix;
}
else if (strlen (imported_name_prefix) > 0)
{
gdb::unique_xmalloc_ptr<char> temp;
temp = typename_concat (imported_name_prefix, imported_name, 0, cu);
canonical_name = obstack_strdup (&objfile->objfile_obstack, temp.get ());
}
else
canonical_name = imported_name;
if (die->tag == DW_TAG_imported_module
&& cu->lang () == language_fortran)
for (child_die = die->child; child_die && child_die->tag;
child_die = child_die->sibling)
{
/* DWARF-4: A Fortran use statement with a “rename list” may be
represented by an imported module entry with an import attribute
referring to the module and owned entries corresponding to those
entities that are renamed as part of being imported. */
if (child_die->tag != DW_TAG_imported_declaration)
{
complaint (_("child DW_TAG_imported_declaration expected "
"- DIE at %s [in module %s]"),
sect_offset_str (child_die->sect_off),
objfile_name (objfile));
continue;
}
import_attr = dwarf2_attr (child_die, DW_AT_import, cu);
if (import_attr == NULL)
{
complaint (_("Tag '%s' has no DW_AT_import"),
dwarf_tag_name (child_die->tag));
continue;
}
imported_cu = cu;
imported_die = follow_die_ref_or_sig (child_die, import_attr,
&imported_cu);
imported_name = dwarf2_name (imported_die, imported_cu);
if (imported_name == NULL)
{
complaint (_("child DW_TAG_imported_declaration has unknown "
"imported name - DIE at %s [in module %s]"),
sect_offset_str (child_die->sect_off),
objfile_name (objfile));
continue;
}
excludes.push_back (imported_name);
process_die (child_die, cu);
}
add_using_directive (using_directives (cu),
import_prefix,
canonical_name,
import_alias,
imported_declaration,
excludes,
read_decl_line (die, cu),
&objfile->objfile_obstack);
}
file_and_directory &
find_file_and_directory (struct die_info *die, struct dwarf2_cu *cu)
{
if (cu->per_cu->fnd != nullptr)
return *cu->per_cu->fnd;
/* Find the filename. Do not use dwarf2_name here, since the filename
is not a source language identifier. */
file_and_directory res (dwarf2_string_attr (die, DW_AT_name, cu),
dwarf2_string_attr (die, DW_AT_comp_dir, cu));
if (res.get_comp_dir () == nullptr
&& cu->producer_is_gcc_lt_4_3 ()
&& res.get_name () != nullptr
&& IS_ABSOLUTE_PATH (res.get_name ()))
{
res.set_comp_dir (ldirname (res.get_name ()));
res.set_name (make_unique_xstrdup (lbasename (res.get_name ())));
}
cu->per_cu->fnd = std::make_unique<file_and_directory> (std::move (res));
return *cu->per_cu->fnd;
}
/* Handle DW_AT_stmt_list for a compilation unit.
DIE is the DW_TAG_compile_unit die for CU.
COMP_DIR is the compilation directory. LOWPC is passed to
dwarf_decode_lines. See dwarf_decode_lines comments about it. */
static void
handle_DW_AT_stmt_list (struct die_info *die, struct dwarf2_cu *cu,
const file_and_directory &fnd, unrelocated_addr lowpc,
bool have_code) /* ARI: editCase function */
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct attribute *attr;
hashval_t line_header_local_hash;
void **slot;
int decode_mapping;
gdb_assert (! cu->per_cu->is_debug_types);
attr = dwarf2_attr (die, DW_AT_stmt_list, cu);
if (attr == NULL || !attr->form_is_unsigned ())
return;
sect_offset line_offset = (sect_offset) attr->as_unsigned ();
/* The line header hash table is only created if needed (it exists to
prevent redundant reading of the line table for partial_units).
If we're given a partial_unit, we'll need it. If we're given a
compile_unit, then use the line header hash table if it's already
created, but don't create one just yet. */
if (per_objfile->line_header_hash == NULL
&& die->tag == DW_TAG_partial_unit)
{
per_objfile->line_header_hash
.reset (htab_create_alloc (127, line_header_hash_voidp,
line_header_eq_voidp,
htab_delete_entry<line_header>,
xcalloc, xfree));
}
line_header line_header_local (line_offset, cu->per_cu->is_dwz);
line_header_local_hash = line_header_hash (&line_header_local);
if (per_objfile->line_header_hash != NULL)
{
slot = htab_find_slot_with_hash (per_objfile->line_header_hash.get (),
&line_header_local,
line_header_local_hash, NO_INSERT);
/* For DW_TAG_compile_unit we need info like symtab::linetable which
is not present in *SLOT (since if there is something in *SLOT then
it will be for a partial_unit). */
if (die->tag == DW_TAG_partial_unit && slot != NULL)
{
gdb_assert (*slot != NULL);
cu->line_header = (struct line_header *) *slot;
return;
}
}
/* dwarf_decode_line_header does not yet provide sufficient information.
We always have to call also dwarf_decode_lines for it. */
line_header_up lh = dwarf_decode_line_header (line_offset, cu,
fnd.get_comp_dir ());
if (lh == NULL)
return;
cu->line_header = lh.release ();
cu->line_header_die_owner = die;
if (per_objfile->line_header_hash == NULL)
slot = NULL;
else
{
slot = htab_find_slot_with_hash (per_objfile->line_header_hash.get (),
&line_header_local,
line_header_local_hash, INSERT);
gdb_assert (slot != NULL);
}
if (slot != NULL && *slot == NULL)
{
/* This newly decoded line number information unit will be owned
by line_header_hash hash table. */
*slot = cu->line_header;
cu->line_header_die_owner = NULL;
}
else
{
/* We cannot free any current entry in (*slot) as that struct line_header
may be already used by multiple CUs. Create only temporary decoded
line_header for this CU - it may happen at most once for each line
number information unit. And if we're not using line_header_hash
then this is what we want as well. */
gdb_assert (die->tag != DW_TAG_partial_unit);
}
decode_mapping = (die->tag != DW_TAG_partial_unit);
/* The have_code check is here because, if LOWPC and HIGHPC are both 0x0,
then there won't be any interesting code in the CU, but a check later on
(in lnp_state_machine::check_line_address) will fail to properly exclude
an entry that was removed via --gc-sections. */
dwarf_decode_lines (cu->line_header, cu, lowpc, decode_mapping && have_code);
}
/* Process DW_TAG_compile_unit or DW_TAG_partial_unit. */
static void
read_file_scope (struct die_info *die, struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
CORE_ADDR lowpc;
struct attribute *attr;
struct die_info *child_die;
unrelocated_addr unrel_low, unrel_high;
get_scope_pc_bounds (die, &unrel_low, &unrel_high, cu);
/* If we didn't find a lowpc, set it to highpc to avoid complaints
from finish_block. */
if (unrel_low == ((unrelocated_addr) -1))
unrel_low = unrel_high;
lowpc = per_objfile->relocate (unrel_low);
file_and_directory &fnd = find_file_and_directory (die, cu);
/* GAS supports generating dwarf-5 info starting version 2.35. Versions
2.35-2.37 generate an incorrect CU name attribute: it's relative,
implicitly prefixing it with the compilation dir. Work around this by
prefixing it with the source dir instead. */
if (cu->header.version == 5 && !IS_ABSOLUTE_PATH (fnd.get_name ())
&& cu->producer_is_gas_lt_2_38 ())
{
attr = dwarf2_attr (die, DW_AT_stmt_list, cu);
if (attr != nullptr && attr->form_is_unsigned ())
{
sect_offset line_offset = (sect_offset) attr->as_unsigned ();
line_header_up lh = dwarf_decode_line_header (line_offset, cu,
fnd.get_comp_dir ());
if (lh->version == 5 && lh->is_valid_file_index (1))
{
std::string dir = lh->include_dir_at (1);
fnd.set_comp_dir (std::move (dir));
}
}
}
cu->start_compunit_symtab (fnd.get_name (), fnd.intern_comp_dir (objfile),
lowpc);
gdb_assert (per_objfile->sym_cu == nullptr);
scoped_restore restore_sym_cu
= make_scoped_restore (&per_objfile->sym_cu, cu);
/* Decode line number information if present. We do this before
processing child DIEs, so that the line header table is available
for DW_AT_decl_file. */
handle_DW_AT_stmt_list (die, cu, fnd, unrel_low, unrel_low != unrel_high);
/* Process all dies in compilation unit. */
if (die->child != NULL)
{
child_die = die->child;
while (child_die && child_die->tag)
{
process_die (child_die, cu);
child_die = child_die->sibling;
}
}
per_objfile->sym_cu = nullptr;
/* Decode macro information, if present. Dwarf 2 macro information
refers to information in the line number info statement program
header, so we can only read it if we've read the header
successfully. */
attr = dwarf2_attr (die, DW_AT_macros, cu);
if (attr == NULL)
attr = dwarf2_attr (die, DW_AT_GNU_macros, cu);
if (attr != nullptr && attr->form_is_unsigned () && cu->line_header)
{
if (dwarf2_attr (die, DW_AT_macro_info, cu))
complaint (_("CU refers to both DW_AT_macros and DW_AT_macro_info"));
dwarf_decode_macros (cu, attr->as_unsigned (), 1);
}
else
{
attr = dwarf2_attr (die, DW_AT_macro_info, cu);
if (attr != nullptr && attr->form_is_unsigned () && cu->line_header)
{
unsigned int macro_offset = attr->as_unsigned ();
dwarf_decode_macros (cu, macro_offset, 0);
}
}
}
void
dwarf2_cu::setup_type_unit_groups (struct die_info *die)
{
int first_time;
struct attribute *attr;
unsigned int i;
struct signatured_type *sig_type;
gdb_assert (per_cu->is_debug_types);
sig_type = (struct signatured_type *) per_cu;
attr = dwarf2_attr (die, DW_AT_stmt_list, this);
/* If we're using .gdb_index (includes -readnow) then
per_cu->type_unit_group may not have been set up yet. */
if (!sig_type->type_unit_group_key.has_value ())
sig_type->type_unit_group_key = get_type_unit_group_key (this, attr);
/* If we've already processed this stmt_list there's no real need to
do it again, we could fake it and just recreate the part we need
(file name,index -> symtab mapping). If data shows this optimization
is useful we can do it then. */
type_unit_group_unshareable *tug_unshare
= per_objfile->get_type_unit_group_unshareable (*sig_type->type_unit_group_key);
first_time = tug_unshare->compunit_symtab == NULL;
/* We have to handle the case of both a missing DW_AT_stmt_list or bad
debug info. */
line_header_up lh;
if (attr != NULL && attr->form_is_unsigned ())
{
sect_offset line_offset = (sect_offset) attr->as_unsigned ();
lh = dwarf_decode_line_header (line_offset, this, nullptr);
}
if (lh == NULL)
{
if (first_time)
start_compunit_symtab ("", NULL, 0);
else
{
gdb_assert (tug_unshare->symtabs == NULL);
gdb_assert (m_builder == nullptr);
struct compunit_symtab *cust = tug_unshare->compunit_symtab;
m_builder = std::make_unique<buildsym_compunit>
(cust->objfile (), "",
cust->dirname (),
cust->language (),
0, cust);
list_in_scope = get_builder ()->get_file_symbols ();
}
return;
}
line_header = lh.release ();
line_header_die_owner = die;
if (first_time)
{
struct compunit_symtab *cust = start_compunit_symtab ("", NULL, 0);
/* Note: We don't assign tu_group->compunit_symtab yet because we're
still initializing it, and our caller (a few levels up)
process_full_type_unit still needs to know if this is the first
time. */
tug_unshare->symtabs
= XOBNEWVEC (&cust->objfile ()->objfile_obstack,
struct symtab *, line_header->file_names_size ());
auto &file_names = line_header->file_names ();
for (i = 0; i < file_names.size (); ++i)
{
file_entry &fe = file_names[i];
dwarf2_start_subfile (this, fe, *line_header);
buildsym_compunit *b = get_builder ();
subfile *sf = b->get_current_subfile ();
if (sf->symtab == nullptr)
{
/* NOTE: start_subfile will recognize when it's been
passed a file it has already seen. So we can't
assume there's a simple mapping from
cu->line_header->file_names to subfiles, plus
cu->line_header->file_names may contain dups. */
const char *name = sf->name.c_str ();
const char *name_for_id = sf->name_for_id.c_str ();
sf->symtab = allocate_symtab (cust, name, name_for_id);
}
fe.symtab = b->get_current_subfile ()->symtab;
tug_unshare->symtabs[i] = fe.symtab;
}
}
else
{
gdb_assert (m_builder == nullptr);
struct compunit_symtab *cust = tug_unshare->compunit_symtab;
m_builder = std::make_unique<buildsym_compunit>
(cust->objfile (), "",
cust->dirname (),
cust->language (),
0, cust);
list_in_scope = get_builder ()->get_file_symbols ();
auto &file_names = line_header->file_names ();
for (i = 0; i < file_names.size (); ++i)
{
file_entry &fe = file_names[i];
fe.symtab = tug_unshare->symtabs[i];
}
}
/* The main symtab is allocated last. Type units don't have DW_AT_name
so they don't have a "real" (so to speak) symtab anyway.
There is later code that will assign the main symtab to all symbols
that don't have one. We need to handle the case of a symbol with a
missing symtab (DW_AT_decl_file) anyway. */
}
/* Process DW_TAG_type_unit.
For TUs we want to skip the first top level sibling if it's not the
actual type being defined by this TU. In this case the first top
level sibling is there to provide context only. */
static void
read_type_unit_scope (struct die_info *die, struct dwarf2_cu *cu)
{
struct die_info *child_die;
/* Initialize (or reinitialize) the machinery for building symtabs.
We do this before processing child DIEs, so that the line header table
is available for DW_AT_decl_file. */
cu->setup_type_unit_groups (die);
if (die->child != NULL)
{
child_die = die->child;
while (child_die && child_die->tag)
{
process_die (child_die, cu);
child_die = child_die->sibling;
}
}
}
/* DWO/DWP files.
http://gcc.gnu.org/wiki/DebugFission
http://gcc.gnu.org/wiki/DebugFissionDWP
To simplify handling of both DWO files ("object" files with the DWARF info)
and DWP files (a file with the DWOs packaged up into one file), we treat
DWP files as having a collection of virtual DWO files. */
/* Lookup DWO file DWO_NAME. */
static dwo_file *
lookup_dwo_file (dwarf2_per_bfd *per_bfd, const char *dwo_name,
const char *comp_dir)
{
auto it = per_bfd->dwo_files.find (dwo_file_search {dwo_name, comp_dir});
return it != per_bfd->dwo_files.end () ? it->get() : nullptr;
}
/* Create the dwo_units for the CUs in a DWO_FILE.
Note: This function processes DWO files only, not DWP files. */
static void
create_cus_hash_table (dwarf2_cu *cu, dwo_file &dwo_file)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
const gdb_byte *info_ptr, *end_ptr;
auto &section = dwo_file.sections.info;
section.read (objfile);
info_ptr = section.buffer;
if (info_ptr == NULL)
return;
dwarf_read_debug_printf ("Reading %s for %s:",
section.get_name (),
section.get_file_name ());
end_ptr = info_ptr + section.size;
while (info_ptr < end_ptr)
{
sect_offset sect_off = (sect_offset) (info_ptr - section.buffer);
/* The length of the CU gets set by the cutu_reader just below. */
dwarf2_per_cu per_cu (per_bfd, &section, sect_off, 0 /* length */,
false /* is_dwz */);
cutu_reader reader (&per_cu, per_objfile, language_minimal,
cu, &dwo_file);
info_ptr += per_cu.length ();
if (reader.is_dummy())
continue;
std::optional<ULONGEST> signature
= lookup_dwo_id (cu, reader.top_level_die ());
if (!signature.has_value ())
{
complaint (_(DWARF_ERROR_PREFIX
"debug entry at offset %s is missing its dwo_id"
" [in module %s]"),
sect_offset_str (sect_off),
dwo_file.dwo_name.c_str ());
continue;
}
dwo_unit *dwo_unit = OBSTACK_ZALLOC (&per_bfd->obstack, struct dwo_unit);
dwo_unit->dwo_file = &dwo_file;
dwo_unit->signature = *signature;
dwo_unit->section = &section;
dwo_unit->sect_off = sect_off;
dwo_unit->length = per_cu.length ();
dwarf_read_debug_printf (" offset %s, dwo_id %s",
sect_offset_str (sect_off),
hex_string (dwo_unit->signature));
auto [it, inserted] = dwo_file.cus.emplace (dwo_unit);
if (!inserted)
complaint (_("debug cu entry at offset %s is duplicate to"
" the entry at offset %s, signature %s"),
sect_offset_str (sect_off),
sect_offset_str ((*it)->sect_off),
hex_string (dwo_unit->signature));
}
}
/* DWP file .debug_{cu,tu}_index section format:
[ref: http://gcc.gnu.org/wiki/DebugFissionDWP]
[ref: http://dwarfstd.org/doc/DWARF5.pdf, sect 7.3.5 "DWARF Package Files"]
DWP Versions 1 & 2 are older, pre-standard format versions. The first
officially standard DWP format was published with DWARF v5 and is called
Version 5. There are no versions 3 or 4.
DWP Version 1:
Both index sections have the same format, and serve to map a 64-bit
signature to a set of section numbers. Each section begins with a header,
followed by a hash table of 64-bit signatures, a parallel table of 32-bit
indexes, and a pool of 32-bit section numbers. The index sections will be
aligned at 8-byte boundaries in the file.
The index section header consists of:
V, 32 bit version number
-, 32 bits unused
N, 32 bit number of compilation units or type units in the index
M, 32 bit number of slots in the hash table
Numbers are recorded using the byte order of the application binary.
The hash table begins at offset 16 in the section, and consists of an array
of M 64-bit slots. Each slot contains a 64-bit signature (using the byte
order of the application binary). Unused slots in the hash table are 0.
(We rely on the extreme unlikeliness of a signature being exactly 0.)
The parallel table begins immediately after the hash table
(at offset 16 + 8 * M from the beginning of the section), and consists of an
array of 32-bit indexes (using the byte order of the application binary),
corresponding 1-1 with slots in the hash table. Each entry in the parallel
table contains a 32-bit index into the pool of section numbers. For unused
hash table slots, the corresponding entry in the parallel table will be 0.
The pool of section numbers begins immediately following the hash table
(at offset 16 + 12 * M from the beginning of the section). The pool of
section numbers consists of an array of 32-bit words (using the byte order
of the application binary). Each item in the array is indexed starting
from 0. The hash table entry provides the index of the first section
number in the set. Additional section numbers in the set follow, and the
set is terminated by a 0 entry (section number 0 is not used in ELF).
In each set of section numbers, the .debug_info.dwo or .debug_types.dwo
section must be the first entry in the set, and the .debug_abbrev.dwo must
be the second entry. Other members of the set may follow in any order.
---
DWP Versions 2 and 5:
DWP Versions 2 and 5 combine all the .debug_info, etc. sections into one,
and the entries in the index tables are now offsets into these sections.
CU offsets begin at 0. TU offsets begin at the size of the .debug_info
section.
Index Section Contents:
Header
Hash Table of Signatures dwp_hash_table.hash_table
Parallel Table of Indices dwp_hash_table.unit_table
Table of Section Offsets dwp_hash_table.{v2|v5}.{section_ids,offsets}
Table of Section Sizes dwp_hash_table.{v2|v5}.sizes
The index section header consists of:
V, 32 bit version number
L, 32 bit number of columns in the table of section offsets
N, 32 bit number of compilation units or type units in the index
M, 32 bit number of slots in the hash table
Numbers are recorded using the byte order of the application binary.
The hash table has the same format as version 1.
The parallel table of indices has the same format as version 1,
except that the entries are origin-1 indices into the table of sections
offsets and the table of section sizes.
The table of offsets begins immediately following the parallel table
(at offset 16 + 12 * M from the beginning of the section). The table is
a two-dimensional array of 32-bit words (using the byte order of the
application binary), with L columns and N+1 rows, in row-major order.
Each row in the array is indexed starting from 0. The first row provides
a key to the remaining rows: each column in this row provides an identifier
for a debug section, and the offsets in the same column of subsequent rows
refer to that section. The section identifiers for Version 2 are:
DW_SECT_INFO 1 .debug_info.dwo
DW_SECT_TYPES 2 .debug_types.dwo
DW_SECT_ABBREV 3 .debug_abbrev.dwo
DW_SECT_LINE 4 .debug_line.dwo
DW_SECT_LOC 5 .debug_loc.dwo
DW_SECT_STR_OFFSETS 6 .debug_str_offsets.dwo
DW_SECT_MACINFO 7 .debug_macinfo.dwo
DW_SECT_MACRO 8 .debug_macro.dwo
The section identifiers for Version 5 are:
DW_SECT_INFO_V5 1 .debug_info.dwo
DW_SECT_RESERVED_V5 2 --
DW_SECT_ABBREV_V5 3 .debug_abbrev.dwo
DW_SECT_LINE_V5 4 .debug_line.dwo
DW_SECT_LOCLISTS_V5 5 .debug_loclists.dwo
DW_SECT_STR_OFFSETS_V5 6 .debug_str_offsets.dwo
DW_SECT_MACRO_V5 7 .debug_macro.dwo
DW_SECT_RNGLISTS_V5 8 .debug_rnglists.dwo
The offsets provided by the CU and TU index sections are the base offsets
for the contributions made by each CU or TU to the corresponding section
in the package file. Each CU and TU header contains an abbrev_offset
field, used to find the abbreviations table for that CU or TU within the
contribution to the .debug_abbrev.dwo section for that CU or TU, and should
be interpreted as relative to the base offset given in the index section.
Likewise, offsets into .debug_line.dwo from DW_AT_stmt_list attributes
should be interpreted as relative to the base offset for .debug_line.dwo,
and offsets into other debug sections obtained from DWARF attributes should
also be interpreted as relative to the corresponding base offset.
The table of sizes begins immediately following the table of offsets.
Like the table of offsets, it is a two-dimensional array of 32-bit words,
with L columns and N rows, in row-major order. Each row in the array is
indexed starting from 1 (row 0 is shared by the two tables).
---
Hash table lookup is handled the same in version 1 and 2:
We assume that N and M will not exceed 2^32 - 1.
The size of the hash table, M, must be 2^k such that 2^k > 3*N/2.
Given a 64-bit compilation unit signature or a type signature S, an entry
in the hash table is located as follows:
1) Calculate a primary hash H = S & MASK(k), where MASK(k) is a mask with
the low-order k bits all set to 1.
2) Calculate a secondary hash H' = (((S >> 32) & MASK(k)) | 1).
3) If the hash table entry at index H matches the signature, use that
entry. If the hash table entry at index H is unused (all zeroes),
terminate the search: the signature is not present in the table.
4) Let H = (H + H') modulo M. Repeat at Step 3.
Because M > N and H' and M are relatively prime, the search is guaranteed
to stop at an unused slot or find the match. */
/* Create a hash table to map DWO IDs to their CU/TU entry in
.debug_{info,types}.dwo in DWP_FILE.
Returns NULL if there isn't one.
Note: This function processes DWP files only, not DWO files. */
static struct dwp_hash_table *
create_dwp_hash_table (dwarf2_per_objfile *per_objfile,
struct dwp_file *dwp_file, int is_debug_types)
{
struct objfile *objfile = per_objfile->objfile;
bfd *dbfd = dwp_file->dbfd.get ();
const gdb_byte *index_ptr, *index_end;
struct dwarf2_section_info *index;
uint32_t version, nr_columns, nr_units, nr_slots;
struct dwp_hash_table *htab;
if (is_debug_types)
index = &dwp_file->sections.tu_index;
else
index = &dwp_file->sections.cu_index;
if (index->empty ())
return NULL;
index->read (objfile);
index_ptr = index->buffer;
index_end = index_ptr + index->size;
/* For Version 5, the version is really 2 bytes of data & 2 bytes of padding.
For now it's safe to just read 4 bytes (particularly as it's difficult to
tell if you're dealing with Version 5 before you've read the version). */
version = read_4_bytes (dbfd, index_ptr);
index_ptr += 4;
if (version == 2 || version == 5)
nr_columns = read_4_bytes (dbfd, index_ptr);
else
nr_columns = 0;
index_ptr += 4;
nr_units = read_4_bytes (dbfd, index_ptr);
index_ptr += 4;
nr_slots = read_4_bytes (dbfd, index_ptr);
index_ptr += 4;
if (version != 1 && version != 2 && version != 5)
{
error (_(DWARF_ERROR_PREFIX
"unsupported DWP file version (%s) [in module %s]"),
pulongest (version), dwp_file->name);
}
if (nr_slots != (nr_slots & -nr_slots))
{
error (_(DWARF_ERROR_PREFIX
"number of slots in DWP hash table (%s) is not power of 2"
" [in module %s]"),
pulongest (nr_slots), dwp_file->name);
}
htab = OBSTACK_ZALLOC (&per_objfile->per_bfd->obstack, struct dwp_hash_table);
htab->version = version;
htab->nr_columns = nr_columns;
htab->nr_units = nr_units;
htab->nr_slots = nr_slots;
htab->hash_table = index_ptr;
htab->unit_table = htab->hash_table + sizeof (uint64_t) * nr_slots;
/* Exit early if the table is empty. */
if (nr_slots == 0 || nr_units == 0
|| (version == 2 && nr_columns == 0)
|| (version == 5 && nr_columns == 0))
{
/* All must be zero. */
if (nr_slots != 0 || nr_units != 0
|| (version == 2 && nr_columns != 0)
|| (version == 5 && nr_columns != 0))
{
complaint (_("Empty DWP but nr_slots,nr_units,nr_columns not"
" all zero [in modules %s]"),
dwp_file->name);
}
return htab;
}
if (version == 1)
{
htab->section_pool.v1.indices =
htab->unit_table + sizeof (uint32_t) * nr_slots;
/* It's harder to decide whether the section is too small in v1.
V1 is deprecated anyway so we punt. */
}
else if (version == 2)
{
const gdb_byte *ids_ptr = htab->unit_table + sizeof (uint32_t) * nr_slots;
int *ids = htab->section_pool.v2.section_ids;
size_t sizeof_ids = sizeof (htab->section_pool.v2.section_ids);
/* Reverse map for error checking. */
int ids_seen[DW_SECT_MAX + 1];
int i;
if (nr_columns < 2)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, too few columns in section table"
" [in module %s]"),
dwp_file->name);
}
if (nr_columns > MAX_NR_V2_DWO_SECTIONS)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, too many columns in section table"
" [in module %s]"),
dwp_file->name);
}
memset (ids, 255, sizeof_ids);
memset (ids_seen, 255, sizeof (ids_seen));
for (i = 0; i < nr_columns; ++i)
{
int id = read_4_bytes (dbfd, ids_ptr + i * sizeof (uint32_t));
if (id < DW_SECT_MIN || id > DW_SECT_MAX)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, bad section id %d in section table"
" [in module %s]"),
id, dwp_file->name);
}
if (ids_seen[id] != -1)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, duplicate section"
" id %d in section table [in module %s]"),
id, dwp_file->name);
}
ids_seen[id] = i;
ids[i] = id;
}
/* Must have exactly one info or types section. */
if (((ids_seen[DW_SECT_INFO] != -1)
+ (ids_seen[DW_SECT_TYPES] != -1))
!= 1)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, missing/duplicate"
" DWO info/types section [in module %s]"),
dwp_file->name);
}
/* Must have an abbrev section. */
if (ids_seen[DW_SECT_ABBREV] == -1)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, missing DWO abbrev section"
" [in module %s]"),
dwp_file->name);
}
htab->section_pool.v2.offsets = ids_ptr + sizeof (uint32_t) * nr_columns;
htab->section_pool.v2.sizes =
htab->section_pool.v2.offsets + (sizeof (uint32_t)
* nr_units * nr_columns);
if ((htab->section_pool.v2.sizes + (sizeof (uint32_t)
* nr_units * nr_columns))
> index_end)
{
error (_(DWARF_ERROR_PREFIX
"DWP index section is corrupt (too small) [in module %s]"),
dwp_file->name);
}
}
else /* version == 5 */
{
const gdb_byte *ids_ptr = htab->unit_table + sizeof (uint32_t) * nr_slots;
int *ids = htab->section_pool.v5.section_ids;
size_t sizeof_ids = sizeof (htab->section_pool.v5.section_ids);
/* Reverse map for error checking. */
int ids_seen[DW_SECT_MAX_V5 + 1];
if (nr_columns < 2)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, too few columns in section table"
" [in module %s]"),
dwp_file->name);
}
if (nr_columns > MAX_NR_V5_DWO_SECTIONS)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, too many columns in section table"
" [in module %s]"),
dwp_file->name);
}
memset (ids, 255, sizeof_ids);
memset (ids_seen, 255, sizeof (ids_seen));
for (int i = 0; i < nr_columns; ++i)
{
int id = read_4_bytes (dbfd, ids_ptr + i * sizeof (uint32_t));
if (id < DW_SECT_MIN || id > DW_SECT_MAX_V5)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, bad section id %d in section table"
" [in module %s]"),
id, dwp_file->name);
}
if (ids_seen[id] != -1)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, duplicate section"
" id %d in section table [in module %s]"),
id, dwp_file->name);
}
ids_seen[id] = i;
ids[i] = id;
}
/* Must have seen an info section. */
if (ids_seen[DW_SECT_INFO_V5] == -1)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, missing/duplicate"
" DWO info/types section [in module %s]"),
dwp_file->name);
}
/* Must have an abbrev section. */
if (ids_seen[DW_SECT_ABBREV_V5] == -1)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, missing DWO abbrev section"
" [in module %s]"),
dwp_file->name);
}
htab->section_pool.v5.offsets = ids_ptr + sizeof (uint32_t) * nr_columns;
htab->section_pool.v5.sizes
= htab->section_pool.v5.offsets + (sizeof (uint32_t)
* nr_units * nr_columns);
if ((htab->section_pool.v5.sizes + (sizeof (uint32_t)
* nr_units * nr_columns))
> index_end)
{
error (_(DWARF_ERROR_PREFIX
"DWP index section is corrupt (too small) [in module %s]"),
dwp_file->name);
}
}
return htab;
}
/* Update SECTIONS with the data from SECTP.
This function is like the other "locate" section routines, but in
this context the sections to read comes from the DWP V1 hash table,
not the full ELF section table.
The result is non-zero for success, or zero if an error was found. */
static int
locate_v1_virtual_dwo_sections (asection *sectp,
struct virtual_v1_dwo_sections *sections)
{
const struct dwop_section_names *names = &dwop_section_names;
if (names->abbrev_dwo.matches (sectp->name))
{
/* There can be only one. */
if (sections->abbrev.s.section != NULL)
return 0;
sections->abbrev.s.section = sectp;
sections->abbrev.size = bfd_section_size (sectp);
}
else if (names->info_dwo.matches (sectp->name)
|| names->types_dwo.matches (sectp->name))
{
/* There can be only one. */
if (sections->info_or_types.s.section != NULL)
return 0;
sections->info_or_types.s.section = sectp;
sections->info_or_types.size = bfd_section_size (sectp);
}
else if (names->line_dwo.matches (sectp->name))
{
/* There can be only one. */
if (sections->line.s.section != NULL)
return 0;
sections->line.s.section = sectp;
sections->line.size = bfd_section_size (sectp);
}
else if (names->loc_dwo.matches (sectp->name))
{
/* There can be only one. */
if (sections->loc.s.section != NULL)
return 0;
sections->loc.s.section = sectp;
sections->loc.size = bfd_section_size (sectp);
}
else if (names->macinfo_dwo.matches (sectp->name))
{
/* There can be only one. */
if (sections->macinfo.s.section != NULL)
return 0;
sections->macinfo.s.section = sectp;
sections->macinfo.size = bfd_section_size (sectp);
}
else if (names->macro_dwo.matches (sectp->name))
{
/* There can be only one. */
if (sections->macro.s.section != NULL)
return 0;
sections->macro.s.section = sectp;
sections->macro.size = bfd_section_size (sectp);
}
else if (names->str_offsets_dwo.matches (sectp->name))
{
/* There can be only one. */
if (sections->str_offsets.s.section != NULL)
return 0;
sections->str_offsets.s.section = sectp;
sections->str_offsets.size = bfd_section_size (sectp);
}
else
{
/* No other kind of section is valid. */
return 0;
}
return 1;
}
/* Create a dwo_unit object for the DWO unit with signature SIGNATURE.
UNIT_INDEX is the index of the DWO unit in the DWP hash table.
COMP_DIR is the DW_AT_comp_dir attribute of the referencing CU.
This is for DWP version 1 files. */
static struct dwo_unit *
create_dwo_unit_in_dwp_v1 (dwarf2_per_bfd *per_bfd,
struct dwp_file *dwp_file,
uint32_t unit_index,
const char *comp_dir,
ULONGEST signature, int is_debug_types)
{
const struct dwp_hash_table *dwp_htab =
is_debug_types ? dwp_file->tus : dwp_file->cus;
bfd *dbfd = dwp_file->dbfd.get ();
const char *kind = is_debug_types ? "TU" : "CU";
struct virtual_v1_dwo_sections sections;
int i;
gdb_assert (dwp_file->version == 1);
dwarf_read_debug_printf ("Reading %s %s/%s in DWP V1 file: %s",
kind, pulongest (unit_index), hex_string (signature),
dwp_file->name);
/* Fetch the sections of this DWO unit.
Put a limit on the number of sections we look for so that bad data
doesn't cause us to loop forever. */
#define MAX_NR_V1_DWO_SECTIONS \
(1 /* .debug_info or .debug_types */ \
+ 1 /* .debug_abbrev */ \
+ 1 /* .debug_line */ \
+ 1 /* .debug_loc */ \
+ 1 /* .debug_str_offsets */ \
+ 1 /* .debug_macro or .debug_macinfo */ \
+ 1 /* trailing zero */)
memset (&sections, 0, sizeof (sections));
for (i = 0; i < MAX_NR_V1_DWO_SECTIONS; ++i)
{
asection *sectp;
uint32_t section_nr =
read_4_bytes (dbfd,
dwp_htab->section_pool.v1.indices
+ (unit_index + i) * sizeof (uint32_t));
if (section_nr == 0)
break;
if (section_nr >= dwp_file->num_sections)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, section number too large"
" [in module %s]"),
dwp_file->name);
}
sectp = dwp_file->elf_sections[section_nr];
if (! locate_v1_virtual_dwo_sections (sectp, &sections))
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, invalid section found [in module %s]"),
dwp_file->name);
}
}
if (i < 2
|| sections.info_or_types.empty ()
|| sections.abbrev.empty ())
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, missing DWO sections [in module %s]"),
dwp_file->name);
}
if (i == MAX_NR_V1_DWO_SECTIONS)
{
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, too many DWO sections [in module %s]"),
dwp_file->name);
}
/* It's easier for the rest of the code if we fake a struct dwo_file and
have dwo_unit "live" in that. At least for now.
The DWP file can be made up of a random collection of CUs and TUs.
However, for each CU + set of TUs that came from the same original DWO
file, we can combine them back into a virtual DWO file to save space
(fewer struct dwo_file objects to allocate). Remember that for really
large apps there can be on the order of 8K CUs and 200K TUs, or more. */
std::string virtual_dwo_name =
string_printf ("virtual-dwo/%d-%d-%d-%d",
sections.abbrev.get_id (),
sections.line.get_id (),
sections.loc.get_id (),
sections.str_offsets.get_id ());
/* Can we use an existing virtual DWO file? */
dwo_file *dwo_file
= lookup_dwo_file (per_bfd, virtual_dwo_name.c_str (), comp_dir);
/* Create one if necessary. */
if (dwo_file == nullptr)
{
dwarf_read_debug_printf ("Creating virtual DWO: %s",
virtual_dwo_name.c_str ());
dwo_file_up new_dwo_file = std::make_unique<struct dwo_file> ();
new_dwo_file->dwo_name = std::move (virtual_dwo_name);
new_dwo_file->comp_dir = comp_dir;
new_dwo_file->sections.abbrev = sections.abbrev;
new_dwo_file->sections.line = sections.line;
new_dwo_file->sections.loc = sections.loc;
new_dwo_file->sections.macinfo = sections.macinfo;
new_dwo_file->sections.macro = sections.macro;
new_dwo_file->sections.str_offsets = sections.str_offsets;
/* The "str" section is global to the entire DWP file. */
new_dwo_file->sections.str = dwp_file->sections.str;
/* The info or types section is assigned below to dwo_unit,
there's no need to record it in dwo_file.
Also, we can't simply record type sections in dwo_file because
we record a pointer into the vector in dwo_unit. As we collect more
types we'll grow the vector and eventually have to reallocate space
for it, invalidating all copies of pointers into the previous
contents. */
auto [it, inserted]
= per_bfd->dwo_files.emplace (std::move (new_dwo_file));
gdb_assert (inserted);
dwo_file = it->get ();
}
else
dwarf_read_debug_printf ("Using existing virtual DWO: %s",
virtual_dwo_name.c_str ());
dwo_unit *dwo_unit = OBSTACK_ZALLOC (&per_bfd->obstack, struct dwo_unit);
dwo_unit->dwo_file = dwo_file;
dwo_unit->signature = signature;
dwo_unit->section = XOBNEW (&per_bfd->obstack, struct dwarf2_section_info);
*dwo_unit->section = sections.info_or_types;
/* dwo_unit->{offset,length,type_offset_in_tu} are set later. */
return dwo_unit;
}
/* Subroutine of create_dwo_unit_in_dwp_v2 and create_dwo_unit_in_dwp_v5 to
simplify them. Given a pointer to the containing section SECTION, and
OFFSET,SIZE of the piece within that section used by a TU/CU, return a
virtual section of just that piece. */
static struct dwarf2_section_info
create_dwp_v2_or_v5_section (dwarf2_per_bfd *per_bfd,
struct dwarf2_section_info *section,
bfd_size_type offset, bfd_size_type size)
{
struct dwarf2_section_info result;
asection *sectp;
gdb_assert (section != NULL);
gdb_assert (!section->is_virtual);
memset (&result, 0, sizeof (result));
result.s.containing_section = section;
result.is_virtual = true;
if (size == 0)
return result;
sectp = section->get_bfd_section ();
/* Flag an error if the piece denoted by OFFSET,SIZE is outside the
bounds of the real section. This is a pretty-rare event, so just
flag an error (easier) instead of a warning and trying to cope. */
if (sectp == NULL
|| offset + size > bfd_section_size (sectp))
{
error (_(DWARF_ERROR_PREFIX
"Bad DWP V2 or V5 section info, doesn't fit in section %s"
" [in module %s]"),
sectp ? bfd_section_name (sectp) : "<unknown>",
per_bfd->filename ());
}
result.virtual_offset = offset;
result.size = size;
gdb_assert (section->readin);
result.readin = true;
result.buffer = section->buffer + offset;
return result;
}
/* Create a dwo_unit object for the DWO unit with signature SIGNATURE.
UNIT_INDEX is the index of the DWO unit in the DWP hash table.
COMP_DIR is the DW_AT_comp_dir attribute of the referencing CU.
This is for DWP version 2 files. */
static struct dwo_unit *
create_dwo_unit_in_dwp_v2 (dwarf2_per_bfd *per_bfd,
struct dwp_file *dwp_file,
uint32_t unit_index,
const char *comp_dir,
ULONGEST signature, int is_debug_types)
{
const struct dwp_hash_table *dwp_htab =
is_debug_types ? dwp_file->tus : dwp_file->cus;
bfd *dbfd = dwp_file->dbfd.get ();
const char *kind = is_debug_types ? "TU" : "CU";
struct virtual_v2_or_v5_dwo_sections sections;
int i;
gdb_assert (dwp_file->version == 2);
dwarf_read_debug_printf ("Reading %s %s/%s in DWP V2 file: %s",
kind, pulongest (unit_index), hex_string (signature),
dwp_file->name);
/* Fetch the section offsets of this DWO unit. */
memset (&sections, 0, sizeof (sections));
for (i = 0; i < dwp_htab->nr_columns; ++i)
{
uint32_t offset = read_4_bytes (dbfd,
dwp_htab->section_pool.v2.offsets
+ (((unit_index - 1) * dwp_htab->nr_columns
+ i)
* sizeof (uint32_t)));
uint32_t size = read_4_bytes (dbfd,
dwp_htab->section_pool.v2.sizes
+ (((unit_index - 1) * dwp_htab->nr_columns
+ i)
* sizeof (uint32_t)));
switch (dwp_htab->section_pool.v2.section_ids[i])
{
case DW_SECT_INFO:
case DW_SECT_TYPES:
sections.info_or_types_offset = offset;
sections.info_or_types_size = size;
break;
case DW_SECT_ABBREV:
sections.abbrev_offset = offset;
sections.abbrev_size = size;
break;
case DW_SECT_LINE:
sections.line_offset = offset;
sections.line_size = size;
break;
case DW_SECT_LOC:
sections.loc_offset = offset;
sections.loc_size = size;
break;
case DW_SECT_STR_OFFSETS:
sections.str_offsets_offset = offset;
sections.str_offsets_size = size;
break;
case DW_SECT_MACINFO:
sections.macinfo_offset = offset;
sections.macinfo_size = size;
break;
case DW_SECT_MACRO:
sections.macro_offset = offset;
sections.macro_size = size;
break;
}
}
/* It's easier for the rest of the code if we fake a struct dwo_file and
have dwo_unit "live" in that. At least for now.
The DWP file can be made up of a random collection of CUs and TUs.
However, for each CU + set of TUs that came from the same original DWO
file, we can combine them back into a virtual DWO file to save space
(fewer struct dwo_file objects to allocate). Remember that for really
large apps there can be on the order of 8K CUs and 200K TUs, or more. */
std::string virtual_dwo_name =
string_printf ("virtual-dwo/%ld-%ld-%ld-%ld",
(long) (sections.abbrev_size ? sections.abbrev_offset : 0),
(long) (sections.line_size ? sections.line_offset : 0),
(long) (sections.loc_size ? sections.loc_offset : 0),
(long) (sections.str_offsets_size
? sections.str_offsets_offset : 0));
/* Can we use an existing virtual DWO file? */
dwo_file *dwo_file
= lookup_dwo_file (per_bfd, virtual_dwo_name.c_str (), comp_dir);
/* Create one if necessary. */
if (dwo_file == nullptr)
{
dwarf_read_debug_printf ("Creating virtual DWO: %s",
virtual_dwo_name.c_str ());
dwo_file_up new_dwo_file = std::make_unique<struct dwo_file> ();
new_dwo_file->dwo_name = std::move (virtual_dwo_name);
new_dwo_file->comp_dir = comp_dir;
new_dwo_file->sections.abbrev
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.abbrev,
sections.abbrev_offset,
sections.abbrev_size);
new_dwo_file->sections.line
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.line,
sections.line_offset,
sections.line_size);
new_dwo_file->sections.loc
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.loc,
sections.loc_offset, sections.loc_size);
new_dwo_file->sections.macinfo
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.macinfo,
sections.macinfo_offset,
sections.macinfo_size);
new_dwo_file->sections.macro
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.macro,
sections.macro_offset,
sections.macro_size);
new_dwo_file->sections.str_offsets
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.str_offsets,
sections.str_offsets_offset,
sections.str_offsets_size);
/* The "str" section is global to the entire DWP file. */
new_dwo_file->sections.str = dwp_file->sections.str;
/* The info or types section is assigned below to dwo_unit,
there's no need to record it in dwo_file.
Also, we can't simply record type sections in dwo_file because
we record a pointer into the vector in dwo_unit. As we collect more
types we'll grow the vector and eventually have to reallocate space
for it, invalidating all copies of pointers into the previous
contents. */
auto [it, inserted]
= per_bfd->dwo_files.emplace (std::move (new_dwo_file));
gdb_assert (inserted);
dwo_file = it->get ();
}
else
dwarf_read_debug_printf ("Using existing virtual DWO: %s",
virtual_dwo_name.c_str ());
dwo_unit *dwo_unit = OBSTACK_ZALLOC (&per_bfd->obstack, struct dwo_unit);
dwo_unit->dwo_file = dwo_file;
dwo_unit->signature = signature;
dwo_unit->section = XOBNEW (&per_bfd->obstack, struct dwarf2_section_info);
*dwo_unit->section = create_dwp_v2_or_v5_section
(per_bfd,
is_debug_types
? &dwp_file->sections.types
: &dwp_file->sections.info,
sections.info_or_types_offset,
sections.info_or_types_size);
/* dwo_unit->{offset,length,type_offset_in_tu} are set later. */
return dwo_unit;
}
/* Create a dwo_unit object for the DWO unit with signature SIGNATURE.
UNIT_INDEX is the index of the DWO unit in the DWP hash table.
COMP_DIR is the DW_AT_comp_dir attribute of the referencing CU.
This is for DWP version 5 files. */
static struct dwo_unit *
create_dwo_unit_in_dwp_v5 (dwarf2_per_bfd *per_bfd,
struct dwp_file *dwp_file,
uint32_t unit_index,
const char *comp_dir,
ULONGEST signature, int is_debug_types)
{
const struct dwp_hash_table *dwp_htab
= is_debug_types ? dwp_file->tus : dwp_file->cus;
bfd *dbfd = dwp_file->dbfd.get ();
const char *kind = is_debug_types ? "TU" : "CU";
struct virtual_v2_or_v5_dwo_sections sections {};
gdb_assert (dwp_file->version == 5);
dwarf_read_debug_printf ("Reading %s %s/%s in DWP V5 file: %s",
kind, pulongest (unit_index), hex_string (signature),
dwp_file->name);
/* Fetch the section offsets of this DWO unit. */
/* memset (&sections, 0, sizeof (sections)); */
for (int i = 0; i < dwp_htab->nr_columns; ++i)
{
uint32_t offset = read_4_bytes (dbfd,
dwp_htab->section_pool.v5.offsets
+ (((unit_index - 1)
* dwp_htab->nr_columns
+ i)
* sizeof (uint32_t)));
uint32_t size = read_4_bytes (dbfd,
dwp_htab->section_pool.v5.sizes
+ (((unit_index - 1) * dwp_htab->nr_columns
+ i)
* sizeof (uint32_t)));
switch (dwp_htab->section_pool.v5.section_ids[i])
{
case DW_SECT_ABBREV_V5:
sections.abbrev_offset = offset;
sections.abbrev_size = size;
break;
case DW_SECT_INFO_V5:
sections.info_or_types_offset = offset;
sections.info_or_types_size = size;
break;
case DW_SECT_LINE_V5:
sections.line_offset = offset;
sections.line_size = size;
break;
case DW_SECT_LOCLISTS_V5:
sections.loclists_offset = offset;
sections.loclists_size = size;
break;
case DW_SECT_MACRO_V5:
sections.macro_offset = offset;
sections.macro_size = size;
break;
case DW_SECT_RNGLISTS_V5:
sections.rnglists_offset = offset;
sections.rnglists_size = size;
break;
case DW_SECT_STR_OFFSETS_V5:
sections.str_offsets_offset = offset;
sections.str_offsets_size = size;
break;
case DW_SECT_RESERVED_V5:
default:
break;
}
}
/* It's easier for the rest of the code if we fake a struct dwo_file and
have dwo_unit "live" in that. At least for now.
The DWP file can be made up of a random collection of CUs and TUs.
However, for each CU + set of TUs that came from the same original DWO
file, we can combine them back into a virtual DWO file to save space
(fewer struct dwo_file objects to allocate). Remember that for really
large apps there can be on the order of 8K CUs and 200K TUs, or more. */
std::string virtual_dwo_name =
string_printf ("virtual-dwo/%ld-%ld-%ld-%ld-%ld-%ld",
(long) (sections.abbrev_size ? sections.abbrev_offset : 0),
(long) (sections.line_size ? sections.line_offset : 0),
(long) (sections.loclists_size ? sections.loclists_offset : 0),
(long) (sections.str_offsets_size
? sections.str_offsets_offset : 0),
(long) (sections.macro_size ? sections.macro_offset : 0),
(long) (sections.rnglists_size ? sections.rnglists_offset: 0));
/* Can we use an existing virtual DWO file? */
dwo_file *dwo_file
= lookup_dwo_file (per_bfd, virtual_dwo_name.c_str (), comp_dir);
/* Create one if necessary. */
if (dwo_file == nullptr)
{
dwarf_read_debug_printf ("Creating virtual DWO: %s",
virtual_dwo_name.c_str ());
dwo_file_up new_dwo_file = std::make_unique<struct dwo_file> ();
new_dwo_file->dwo_name = std::move (virtual_dwo_name);
new_dwo_file->comp_dir = comp_dir;
new_dwo_file->sections.abbrev
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.abbrev,
sections.abbrev_offset,
sections.abbrev_size);
new_dwo_file->sections.line
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.line,
sections.line_offset,
sections.line_size);
new_dwo_file->sections.macro
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.macro,
sections.macro_offset,
sections.macro_size);
new_dwo_file->sections.loclists
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.loclists,
sections.loclists_offset,
sections.loclists_size);
new_dwo_file->sections.rnglists
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.rnglists,
sections.rnglists_offset,
sections.rnglists_size);
new_dwo_file->sections.str_offsets
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.str_offsets,
sections.str_offsets_offset,
sections.str_offsets_size);
/* The "str" section is global to the entire DWP file. */
new_dwo_file->sections.str = dwp_file->sections.str;
/* The info or types section is assigned below to dwo_unit,
there's no need to record it in dwo_file.
Also, we can't simply record type sections in dwo_file because
we record a pointer into the vector in dwo_unit. As we collect more
types we'll grow the vector and eventually have to reallocate space
for it, invalidating all copies of pointers into the previous
contents. */
auto [it, inserted]
= per_bfd->dwo_files.emplace (std::move (new_dwo_file));
gdb_assert (inserted);
dwo_file = it->get ();
}
else
dwarf_read_debug_printf ("Using existing virtual DWO: %s",
virtual_dwo_name.c_str ());
dwo_unit *dwo_unit = OBSTACK_ZALLOC (&per_bfd->obstack, struct dwo_unit);
dwo_unit->dwo_file = dwo_file;
dwo_unit->signature = signature;
dwo_unit->section
= XOBNEW (&per_bfd->obstack, struct dwarf2_section_info);
*dwo_unit->section
= create_dwp_v2_or_v5_section (per_bfd, &dwp_file->sections.info,
sections.info_or_types_offset,
sections.info_or_types_size);
/* dwo_unit->{offset,length,type_offset_in_tu} are set later. */
return dwo_unit;
}
/* Lookup the DWO unit with SIGNATURE in DWP_FILE.
Returns NULL if the signature isn't found. */
static struct dwo_unit *
lookup_dwo_unit_in_dwp (dwarf2_per_bfd *per_bfd,
struct dwp_file *dwp_file, const char *comp_dir,
ULONGEST signature, int is_debug_types)
{
const struct dwp_hash_table *dwp_htab =
is_debug_types ? dwp_file->tus : dwp_file->cus;
bfd *dbfd = dwp_file->dbfd.get ();
uint32_t mask = dwp_htab->nr_slots - 1;
uint32_t hash = signature & mask;
uint32_t hash2 = ((signature >> 32) & mask) | 1;
auto &dwo_unit_set
= is_debug_types ? dwp_file->loaded_tus : dwp_file->loaded_cus;
if (auto it = dwo_unit_set.find (signature);
it != dwo_unit_set.end ())
return *it;
/* Use a for loop so that we don't loop forever on bad debug info. */
for (unsigned int i = 0; i < dwp_htab->nr_slots; ++i)
{
ULONGEST signature_in_table;
signature_in_table =
read_8_bytes (dbfd, dwp_htab->hash_table + hash * sizeof (uint64_t));
if (signature_in_table == signature)
{
uint32_t unit_index =
read_4_bytes (dbfd,
dwp_htab->unit_table + hash * sizeof (uint32_t));
dwo_unit *dwo_unit;
if (dwp_file->version == 1)
dwo_unit
= create_dwo_unit_in_dwp_v1 (per_bfd, dwp_file, unit_index,
comp_dir, signature, is_debug_types);
else if (dwp_file->version == 2)
dwo_unit
= create_dwo_unit_in_dwp_v2 (per_bfd, dwp_file, unit_index,
comp_dir, signature, is_debug_types);
else /* version == 5 */
dwo_unit
= create_dwo_unit_in_dwp_v5 (per_bfd, dwp_file, unit_index,
comp_dir, signature, is_debug_types);
auto [it, inserted] = dwo_unit_set.emplace (dwo_unit);
gdb_assert (inserted);
return *it;
}
if (signature_in_table == 0)
return NULL;
hash = (hash + hash2) & mask;
}
error (_(DWARF_ERROR_PREFIX
"bad DWP hash table, lookup didn't terminate [in module %s]"),
dwp_file->name);
}
/* Subroutine of open_dwo_file,open_dwp_file to simplify them.
Open the file specified by FILE_NAME and hand it off to BFD for
preliminary analysis. Return a newly initialized bfd *, which
includes a canonicalized copy of FILE_NAME.
If IS_DWP is TRUE, we're opening a DWP file, otherwise a DWO file.
SEARCH_CWD is true if the current directory is to be searched.
It will be searched before debug-file-directory.
If successful, the file is added to the bfd include table of the
objfile's bfd (see gdb_bfd_record_inclusion).
If unable to find/open the file, return NULL.
NOTE: This function is derived from symfile_bfd_open. */
static gdb_bfd_ref_ptr
try_open_dwop_file (dwarf2_per_bfd *per_bfd, const char *file_name, int is_dwp,
int search_cwd)
{
int desc;
/* Blech. OPF_TRY_CWD_FIRST also disables searching the path list if
FILE_NAME contains a '/'. So we can't use it. Instead prepend "."
to debug_file_directory. */
const char *search_path;
static const char dirname_separator_string[] = { DIRNAME_SEPARATOR, '\0' };
gdb::unique_xmalloc_ptr<char> search_path_holder;
if (search_cwd)
{
const std::string &debug_dir = per_bfd->captured_debug_dir;
if (!debug_dir.empty ())
{
search_path_holder.reset (concat (".", dirname_separator_string,
debug_dir.c_str (),
(char *) NULL));
search_path = search_path_holder.get ();
}
else
search_path = ".";
}
else
search_path = per_bfd->captured_debug_dir.c_str ();
/* Add the path for the executable binary to the list of search paths. */
std::string objfile_dir = ldirname (per_bfd->filename ());
search_path_holder.reset (concat (objfile_dir.c_str (),
dirname_separator_string,
search_path, nullptr));
search_path = search_path_holder.get ();
openp_flags flags = OPF_RETURN_REALPATH;
if (is_dwp)
flags |= OPF_SEARCH_IN_PATH;
gdb::unique_xmalloc_ptr<char> absolute_name;
desc = openp (search_path, flags, file_name, O_RDONLY | O_BINARY,
&absolute_name, per_bfd->captured_cwd.c_str ());
if (desc < 0)
return NULL;
gdb_bfd_ref_ptr sym_bfd (gdb_bfd_open (absolute_name.get (),
gnutarget, desc));
if (sym_bfd == NULL)
return NULL;
if (!bfd_check_format (sym_bfd.get (), bfd_object))
return NULL;
/* Success. Record the bfd as having been included by the objfile's bfd.
This is important because things like demangled_names_hash lives in the
objfile's per_bfd space and may have references to things like symbol
names that live in the DWO/DWP file's per_bfd space. PR 16426. */
gdb_bfd_record_inclusion (per_bfd->obfd, sym_bfd.get ());
return sym_bfd;
}
/* Try to open DWO file FILE_NAME.
COMP_DIR is the DW_AT_comp_dir attribute.
The result is the bfd handle of the file.
If there is a problem finding or opening the file, return NULL.
Upon success, the canonicalized path of the file is stored in the bfd,
same as symfile_bfd_open. */
static gdb_bfd_ref_ptr
open_dwo_file (dwarf2_per_bfd *per_bfd, const char *file_name,
const char *comp_dir)
{
if (IS_ABSOLUTE_PATH (file_name))
return try_open_dwop_file (per_bfd, file_name,
0 /*is_dwp*/, 0 /*search_cwd*/);
/* Before trying the search path, try DWO_NAME in COMP_DIR. */
if (comp_dir != NULL)
{
std::string path_to_try = path_join (comp_dir, file_name);
/* NOTE: If comp_dir is a relative path, this will also try the
search path, which seems useful. */
gdb_bfd_ref_ptr abfd
= try_open_dwop_file (per_bfd, path_to_try.c_str (), 0 /* is_dwp */,
1 /* search_cwd */);
if (abfd != NULL)
return abfd;
}
/* That didn't work, try debug-file-directory, which, despite its name,
is a list of paths. */
if (per_bfd->captured_debug_dir.empty ())
return NULL;
return try_open_dwop_file (per_bfd, file_name, 0 /* is_dwp */,
1 /* search_cwd */);
}
/* This function is mapped across the sections and remembers the offset and
size of each of the DWO debugging sections we are interested in. */
static void
dwarf2_locate_dwo_sections (struct objfile *objfile, bfd *abfd,
asection *sectp, dwo_sections *dwo_sections)
{
const struct dwop_section_names *names = &dwop_section_names;
struct dwarf2_section_info *dw_sect = nullptr;
if (names->abbrev_dwo.matches (sectp->name))
dw_sect = &dwo_sections->abbrev;
else if (names->info_dwo.matches (sectp->name))
dw_sect = &dwo_sections->info;
else if (names->line_dwo.matches (sectp->name))
dw_sect = &dwo_sections->line;
else if (names->loc_dwo.matches (sectp->name))
dw_sect = &dwo_sections->loc;
else if (names->loclists_dwo.matches (sectp->name))
dw_sect = &dwo_sections->loclists;
else if (names->macinfo_dwo.matches (sectp->name))
dw_sect = &dwo_sections->macinfo;
else if (names->macro_dwo.matches (sectp->name))
dw_sect = &dwo_sections->macro;
else if (names->rnglists_dwo.matches (sectp->name))
dw_sect = &dwo_sections->rnglists;
else if (names->str_dwo.matches (sectp->name))
dw_sect = &dwo_sections->str;
else if (names->str_offsets_dwo.matches (sectp->name))
dw_sect = &dwo_sections->str_offsets;
else if (names->types_dwo.matches (sectp->name))
{
struct dwarf2_section_info type_section;
memset (&type_section, 0, sizeof (type_section));
dwo_sections->types.push_back (type_section);
dw_sect = &dwo_sections->types.back ();
}
if (dw_sect != nullptr)
{
dw_sect->s.section = sectp;
dw_sect->size = bfd_section_size (sectp);
dw_sect->read (objfile);
}
}
/* Initialize the use of the DWO file specified by DWO_NAME and referenced
by PER_CU. This is for the non-DWP case.
The result is NULL if DWO_NAME can't be found. */
static dwo_file_up
open_and_init_dwo_file (dwarf2_cu *cu, const char *dwo_name,
const char *comp_dir)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
gdb_bfd_ref_ptr dbfd
= open_dwo_file (per_objfile->per_bfd, dwo_name, comp_dir);
if (dbfd == NULL)
{
dwarf_read_debug_printf ("DWO file not found: %s", dwo_name);
return NULL;
}
dwo_file_up dwo_file = std::make_unique<struct dwo_file> ();
dwo_file->dwo_name = dwo_name;
dwo_file->comp_dir = comp_dir;
dwo_file->dbfd = std::move (dbfd);
for (asection *sec : gdb_bfd_sections (dwo_file->dbfd))
dwarf2_locate_dwo_sections (per_objfile->objfile, dwo_file->dbfd.get (),
sec, &dwo_file->sections);
create_cus_hash_table (cu, *dwo_file);
if (cu->header.version < 5)
create_debug_types_hash_table (per_objfile, dwo_file.get (),
dwo_file->sections.types);
else
create_debug_type_hash_table (per_objfile, dwo_file.get (),
&dwo_file->sections.info, rcuh_kind::COMPILE);
dwarf_read_debug_printf ("DWO file found: %s", dwo_name);
bfd_cache_close (dwo_file->dbfd.get ());
return dwo_file;
}
/* This function is mapped across the sections and remembers the offset and
size of each of the DWP debugging sections common to version 1 and 2 that
we are interested in. */
static void
dwarf2_locate_common_dwp_sections (struct objfile *objfile, bfd *abfd,
asection *sectp, dwp_file *dwp_file)
{
const struct dwop_section_names *names = &dwop_section_names;
unsigned int elf_section_nr = elf_section_data (sectp)->this_idx;
/* Record the ELF section number for later lookup: this is what the
.debug_cu_index,.debug_tu_index tables use in DWP V1. */
gdb_assert (elf_section_nr < dwp_file->num_sections);
dwp_file->elf_sections[elf_section_nr] = sectp;
/* Look for specific sections that we need. */
struct dwarf2_section_info *dw_sect = nullptr;
if (names->str_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.str;
else if (names->cu_index.matches (sectp->name))
dw_sect = &dwp_file->sections.cu_index;
else if (names->tu_index.matches (sectp->name))
dw_sect = &dwp_file->sections.tu_index;
if (dw_sect != nullptr)
{
dw_sect->s.section = sectp;
dw_sect->size = bfd_section_size (sectp);
dw_sect->read (objfile);
}
}
/* This function is mapped across the sections and remembers the offset and
size of each of the DWP version 2 debugging sections that we are interested
in. This is split into a separate function because we don't know if we
have version 1 or 2 or 5 until we parse the cu_index/tu_index sections. */
static void
dwarf2_locate_v2_dwp_sections (struct objfile *objfile, bfd *abfd,
asection *sectp, void *dwp_file_ptr)
{
struct dwp_file *dwp_file = (struct dwp_file *) dwp_file_ptr;
const struct dwop_section_names *names = &dwop_section_names;
unsigned int elf_section_nr = elf_section_data (sectp)->this_idx;
/* Record the ELF section number for later lookup: this is what the
.debug_cu_index,.debug_tu_index tables use in DWP V1. */
gdb_assert (elf_section_nr < dwp_file->num_sections);
dwp_file->elf_sections[elf_section_nr] = sectp;
/* Look for specific sections that we need. */
struct dwarf2_section_info *dw_sect = nullptr;
if (names->abbrev_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.abbrev;
else if (names->info_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.info;
else if (names->line_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.line;
else if (names->loc_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.loc;
else if (names->macinfo_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.macinfo;
else if (names->macro_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.macro;
else if (names->str_offsets_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.str_offsets;
else if (names->types_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.types;
if (dw_sect != nullptr)
{
dw_sect->s.section = sectp;
dw_sect->size = bfd_section_size (sectp);
dw_sect->read (objfile);
}
}
/* This function is mapped across the sections and remembers the offset and
size of each of the DWP version 5 debugging sections that we are interested
in. This is split into a separate function because we don't know if we
have version 1 or 2 or 5 until we parse the cu_index/tu_index sections. */
static void
dwarf2_locate_v5_dwp_sections (struct objfile *objfile, bfd *abfd,
asection *sectp, void *dwp_file_ptr)
{
struct dwp_file *dwp_file = (struct dwp_file *) dwp_file_ptr;
const struct dwop_section_names *names = &dwop_section_names;
unsigned int elf_section_nr = elf_section_data (sectp)->this_idx;
/* Record the ELF section number for later lookup: this is what the
.debug_cu_index,.debug_tu_index tables use in DWP V1. */
gdb_assert (elf_section_nr < dwp_file->num_sections);
dwp_file->elf_sections[elf_section_nr] = sectp;
/* Look for specific sections that we need. */
struct dwarf2_section_info *dw_sect = nullptr;
if (names->abbrev_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.abbrev;
else if (names->info_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.info;
else if (names->line_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.line;
else if (names->loclists_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.loclists;
else if (names->macro_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.macro;
else if (names->rnglists_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.rnglists;
else if (names->str_offsets_dwo.matches (sectp->name))
dw_sect = &dwp_file->sections.str_offsets;
if (dw_sect != nullptr)
{
dw_sect->s.section = sectp;
dw_sect->size = bfd_section_size (sectp);
dw_sect->read (objfile);
}
}
/* Try to open DWP file FILE_NAME.
The result is the bfd handle of the file.
If there is a problem finding or opening the file, return NULL.
Upon success, the canonicalized path of the file is stored in the bfd,
same as symfile_bfd_open. */
static gdb_bfd_ref_ptr
open_dwp_file (dwarf2_per_bfd *per_bfd, const char *file_name)
{
gdb_bfd_ref_ptr abfd
= try_open_dwop_file (per_bfd, file_name, 1 /* is_dwp */,
1 /* search_cwd */);
if (abfd != NULL)
return abfd;
/* Work around upstream bug 15652.
http://sourceware.org/bugzilla/show_bug.cgi?id=15652
[Whether that's a "bug" is debatable, but it is getting in our way.]
We have no real idea where the dwp file is, because gdb's realpath-ing
of the executable's path may have discarded the needed info.
[IWBN if the dwp file name was recorded in the executable, akin to
.gnu_debuglink, but that doesn't exist yet.]
Strip the directory from FILE_NAME and search again. */
if (!per_bfd->captured_debug_dir.empty ())
{
/* Don't implicitly search the current directory here.
If the user wants to search "." to handle this case,
it must be added to debug-file-directory. */
return try_open_dwop_file (per_bfd, lbasename (file_name),
1 /* is_dwp */, 0 /* search_cwd */);
}
return NULL;
}
/* Initialize the use of the DWP file for the current objfile.
By convention the name of the DWP file is ${objfile}.dwp.
The result is NULL if it can't be found. */
static dwp_file_up
open_and_init_dwp_file (dwarf2_per_objfile *per_objfile)
{
struct objfile *objfile = per_objfile->objfile;
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
/* Try to find first .dwp for the binary file before any symbolic links
resolving. */
/* If the objfile is a debug file, find the name of the real binary
file and get the name of dwp file from there. */
std::string dwp_name;
if (objfile->separate_debug_objfile_backlink != NULL)
{
struct objfile *backlink = objfile->separate_debug_objfile_backlink;
const char *backlink_basename = lbasename (backlink->original_name);
dwp_name = ldirname (objfile->original_name) + SLASH_STRING + backlink_basename;
}
else
dwp_name = objfile->original_name;
dwp_name += ".dwp";
gdb_bfd_ref_ptr dbfd (open_dwp_file (per_bfd, dwp_name.c_str ()));
if (dbfd == NULL
&& strcmp (objfile->original_name, objfile_name (objfile)) != 0)
{
/* Try to find .dwp for the binary file after gdb_realpath resolving. */
dwp_name = objfile_name (objfile);
dwp_name += ".dwp";
dbfd = open_dwp_file (per_bfd, dwp_name.c_str ());
}
if (dbfd == NULL)
{
dwarf_read_debug_printf ("DWP file not found: %s", dwp_name.c_str ());
return dwp_file_up ();
}
const char *name = bfd_get_filename (dbfd.get ());
auto dwp_file = std::make_unique<struct dwp_file> (name, std::move (dbfd));
dwp_file->num_sections = elf_numsections (dwp_file->dbfd);
dwp_file->elf_sections
= OBSTACK_CALLOC (&per_bfd->obstack, dwp_file->num_sections, asection *);
for (asection *sec : gdb_bfd_sections (dwp_file->dbfd))
dwarf2_locate_common_dwp_sections (objfile, dwp_file->dbfd.get (), sec,
dwp_file.get ());
dwp_file->cus = create_dwp_hash_table (per_objfile, dwp_file.get (), 0);
dwp_file->tus = create_dwp_hash_table (per_objfile, dwp_file.get (), 1);
/* The DWP file version is stored in the hash table. Oh well. */
if (dwp_file->cus && dwp_file->tus
&& dwp_file->cus->version != dwp_file->tus->version)
{
/* Technically speaking, we should try to limp along, but this is
pretty bizarre. We use pulongest here because that's the established
portability solution (e.g, we cannot use %u for uint32_t). */
error (_(DWARF_ERROR_PREFIX
"DWP file CU version %s doesn't match TU version %s"
" [in DWP file %s]"),
pulongest (dwp_file->cus->version),
pulongest (dwp_file->tus->version), dwp_name.c_str ());
}
if (dwp_file->cus)
dwp_file->version = dwp_file->cus->version;
else if (dwp_file->tus)
dwp_file->version = dwp_file->tus->version;
else
dwp_file->version = 2;
for (asection *sec : gdb_bfd_sections (dwp_file->dbfd))
{
if (dwp_file->version == 2)
dwarf2_locate_v2_dwp_sections (objfile, dwp_file->dbfd.get (), sec,
dwp_file.get ());
else
dwarf2_locate_v5_dwp_sections (objfile, dwp_file->dbfd.get (), sec,
dwp_file.get ());
}
dwarf_read_debug_printf ("DWP file found: %s", dwp_file->name);
dwarf_read_debug_printf (" %s CUs, %s TUs",
pulongest (dwp_file->cus ? dwp_file->cus->nr_units : 0),
pulongest (dwp_file->tus ? dwp_file->tus->nr_units : 0));
bfd_cache_close (dwp_file->dbfd.get ());
return dwp_file;
}
/* Wrapper around open_and_init_dwp_file, only open it once. */
static struct dwp_file *
get_dwp_file (dwarf2_per_objfile *per_objfile)
{
if (!per_objfile->per_bfd->dwp_checked)
{
per_objfile->per_bfd->dwp_file = open_and_init_dwp_file (per_objfile);
per_objfile->per_bfd->dwp_checked = 1;
}
return per_objfile->per_bfd->dwp_file.get ();
}
/* Subroutine of lookup_dwo_comp_unit, lookup_dwo_type_unit.
Look up the CU/TU with signature SIGNATURE, either in DWO file DWO_NAME
or in the DWP file for the objfile, referenced by THIS_UNIT.
If non-NULL, comp_dir is the DW_AT_comp_dir attribute.
IS_DEBUG_TYPES is non-zero if reading a TU, otherwise read a CU.
This is called, for example, when wanting to read a variable with a
complex location. Therefore we don't want to do file i/o for every call.
Therefore we don't want to look for a DWO file on every call.
Therefore we first see if we've already seen SIGNATURE in a DWP file,
then we check if we've already seen DWO_NAME, and only THEN do we check
for a DWO file.
The result is a pointer to the dwo_unit object or NULL if we didn't find it
(dwo_id mismatch or couldn't find the DWO/DWP file). */
static struct dwo_unit *
lookup_dwo_cutu (dwarf2_cu *cu, const char *dwo_name, const char *comp_dir,
ULONGEST signature, int is_debug_types)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
struct objfile *objfile = per_objfile->objfile;
const char *kind = is_debug_types ? "TU" : "CU";
struct dwp_file *dwp_file;
/* First see if there's a DWP file.
If we have a DWP file but didn't find the DWO inside it, don't
look for the original DWO file. It makes gdb behave differently
depending on whether one is debugging in the build tree. */
dwp_file = get_dwp_file (per_objfile);
if (dwp_file != NULL)
{
const struct dwp_hash_table *dwp_htab =
is_debug_types ? dwp_file->tus : dwp_file->cus;
if (dwp_htab != NULL)
{
struct dwo_unit *dwo_cutu =
lookup_dwo_unit_in_dwp (per_bfd, dwp_file, comp_dir, signature,
is_debug_types);
if (dwo_cutu != NULL)
{
dwarf_read_debug_printf ("Virtual DWO %s %s found: @%s",
kind, hex_string (signature),
host_address_to_string (dwo_cutu));
return dwo_cutu;
}
}
}
else
{
/* No DWP file, look for the DWO file. */
dwo_file *dwo_file = lookup_dwo_file (per_bfd, dwo_name, comp_dir);
if (dwo_file == nullptr)
{
/* Read in the file and build a table of the CUs/TUs it contains.
NOTE: This will be nullptr if unable to open the file. */
dwo_file_up new_dwo_file
= open_and_init_dwo_file (cu, dwo_name, comp_dir);
if (new_dwo_file != nullptr)
{
auto [it, inserted]
= per_bfd->dwo_files.emplace (std::move (new_dwo_file));
gdb_assert (inserted);
dwo_file = (*it).get ();
}
}
if (dwo_file != NULL)
{
struct dwo_unit *dwo_cutu = NULL;
if (is_debug_types && !dwo_file->tus.empty ())
{
if (auto it = dwo_file->tus.find (signature);
it != dwo_file->tus.end ())
dwo_cutu = *it;
}
else if (!is_debug_types && !dwo_file->cus.empty ())
{
if (auto it = dwo_file->cus.find (signature);
it != dwo_file->cus.end ())
dwo_cutu = *it;
}
if (dwo_cutu != NULL)
{
dwarf_read_debug_printf ("DWO %s %s(%s) found: @%s",
kind, dwo_name, hex_string (signature),
host_address_to_string (dwo_cutu));
return dwo_cutu;
}
}
}
/* We didn't find it. This could mean a dwo_id mismatch, or
someone deleted the DWO/DWP file, or the search path isn't set up
correctly to find the file. */
dwarf_read_debug_printf ("DWO %s %s(%s) not found",
kind, dwo_name, hex_string (signature));
/* This is a warning and not a complaint because it can be caused by
pilot error (e.g., user accidentally deleting the DWO). */
{
/* Print the name of the DWP file if we looked there, helps the user
better diagnose the problem. */
std::string dwp_text;
if (dwp_file != NULL)
dwp_text = string_printf (" [in DWP file %s]",
lbasename (dwp_file->name));
warning (_("Could not find DWO %s %s(%s)%s referenced by %s at offset %s"
" [in module %s]"),
kind, dwo_name, hex_string (signature), dwp_text.c_str (), kind,
sect_offset_str (cu->per_cu->sect_off), objfile_name (objfile));
}
return NULL;
}
/* Lookup the DWO CU DWO_NAME/SIGNATURE referenced from THIS_CU.
See lookup_dwo_cutu_unit for details. */
static struct dwo_unit *
lookup_dwo_comp_unit (dwarf2_cu *cu, const char *dwo_name, const char *comp_dir,
ULONGEST signature)
{
gdb_assert (!cu->per_cu->is_debug_types);
return lookup_dwo_cutu (cu, dwo_name, comp_dir, signature, 0);
}
/* Lookup the DWO TU DWO_NAME/SIGNATURE referenced from THIS_TU.
See lookup_dwo_cutu_unit for details. */
static struct dwo_unit *
lookup_dwo_type_unit (dwarf2_cu *cu, const char *dwo_name, const char *comp_dir)
{
gdb_assert (cu->per_cu->is_debug_types);
signatured_type *sig_type = (signatured_type *) cu->per_cu;
return lookup_dwo_cutu (cu, dwo_name, comp_dir, sig_type->signature, 1);
}
/* Traversal function for queue_and_load_all_dwo_tus. */
static int
queue_and_load_dwo_tu (dwo_unit *dwo_unit, dwarf2_cu *cu)
{
ULONGEST signature = dwo_unit->signature;
signatured_type *sig_type = lookup_dwo_signatured_type (cu, signature);
if (sig_type != NULL)
{
/* We pass NULL for DEPENDENT_CU because we don't yet know if there's
a real dependency of PER_CU on SIG_TYPE. That is detected later
while processing PER_CU. */
if (maybe_queue_comp_unit (NULL, sig_type, cu->per_objfile))
load_full_type_unit (sig_type, cu->per_objfile);
cu->per_cu->imported_symtabs.push_back (sig_type);
}
return 1;
}
/* Queue all TUs contained in the DWO of CU to be read in.
The DWO may have the only definition of the type, though it may not be
referenced anywhere in PER_CU. Thus we have to load *all* its TUs.
http://sourceware.org/bugzilla/show_bug.cgi?id=15021 */
static void
queue_and_load_all_dwo_tus (dwarf2_cu *cu)
{
struct dwo_unit *dwo_unit;
struct dwo_file *dwo_file;
gdb_assert (cu != nullptr);
gdb_assert (!cu->per_cu->is_debug_types);
gdb_assert (get_dwp_file (cu->per_objfile) == nullptr);
dwo_unit = cu->dwo_unit;
gdb_assert (dwo_unit != NULL);
dwo_file = dwo_unit->dwo_file;
for (struct dwo_unit *unit : dwo_file->tus)
queue_and_load_dwo_tu (unit, cu);
}
/* Read in various DIEs. */
/* DW_AT_abstract_origin inherits whole DIEs (not just their attributes).
Inherit only the children of the DW_AT_abstract_origin DIE not being
already referenced by DW_AT_abstract_origin from the children of the
current DIE. */
static void
inherit_abstract_dies (struct die_info *die, struct dwarf2_cu *cu)
{
attribute *attr = dwarf2_attr (die, DW_AT_abstract_origin, cu);
if (attr == nullptr)
return;
/* Note that following die references may follow to a die in a
different CU. */
dwarf2_cu *origin_cu = cu;
/* Parent of DIE - referenced by DW_AT_abstract_origin. */
die_info *origin_die = follow_die_ref (die, attr, &origin_cu);
/* We're inheriting ORIGIN's children into the scope we'd put DIE's
symbols in. */
struct pending **origin_previous_list_in_scope = origin_cu->list_in_scope;
origin_cu->list_in_scope = cu->list_in_scope;
if (die->tag != origin_die->tag
&& !(die->tag == DW_TAG_inlined_subroutine
&& origin_die->tag == DW_TAG_subprogram))
complaint (_("DIE %s and its abstract origin %s have different tags"),
sect_offset_str (die->sect_off),
sect_offset_str (origin_die->sect_off));
/* Find if the concrete and abstract trees are structurally the
same. This is a shallow traversal and it is not bullet-proof;
the compiler can trick the debugger into believing that the trees
are isomorphic, whereas they actually are not. However, the
likelihood of this happening is pretty low, and a full-fledged
check would be an overkill. */
bool are_isomorphic = true;
die_info *concrete_child = die->child;
die_info *abstract_child = origin_die->child;
while (concrete_child != nullptr || abstract_child != nullptr)
{
if (concrete_child == nullptr
|| abstract_child == nullptr
|| concrete_child->tag != abstract_child->tag)
{
are_isomorphic = false;
break;
}
concrete_child = concrete_child->sibling;
abstract_child = abstract_child->sibling;
}
/* Walk the origin's children in parallel to the concrete children.
This helps match an origin child in case the debug info misses
DW_AT_abstract_origin attributes. Keep in mind that the abstract
origin tree may not have the same tree structure as the concrete
DIE, though. */
die_info *corresponding_abstract_child
= are_isomorphic ? origin_die->child : nullptr;
std::vector<sect_offset> offsets;
for (die_info *child_die = die->child;
child_die && child_die->tag;
child_die = child_die->sibling)
{
/* We are trying to process concrete instance entries:
DW_TAG_call_site DIEs indeed have a DW_AT_abstract_origin tag, but
it's not relevant to our analysis here. i.e. detecting DIEs that are
present in the abstract instance but not referenced in the concrete
one. */
if (child_die->tag == DW_TAG_call_site
|| child_die->tag == DW_TAG_GNU_call_site)
{
if (are_isomorphic)
corresponding_abstract_child
= corresponding_abstract_child->sibling;
continue;
}
/* For each CHILD_DIE, find the corresponding child of
ORIGIN_DIE. If there is more than one layer of
DW_AT_abstract_origin, follow them all; there shouldn't be,
but GCC versions at least through 4.4 generate this (GCC PR
40573). */
die_info *child_origin_die = child_die;
dwarf2_cu *child_origin_cu = cu;
while (true)
{
attr = dwarf2_attr (child_origin_die, DW_AT_abstract_origin,
child_origin_cu);
if (attr == nullptr)
break;
die_info *prev_child_origin_die = child_origin_die;
child_origin_die = follow_die_ref (child_origin_die, attr,
&child_origin_cu);
if (prev_child_origin_die == child_origin_die)
{
/* Handle DIE with self-reference. */
break;
}
}
/* If missing DW_AT_abstract_origin, try the corresponding child
of the origin. Clang emits such lexical scopes. */
if (child_origin_die == child_die
&& dwarf2_attr (child_die, DW_AT_abstract_origin, cu) == nullptr
&& are_isomorphic
&& child_die->tag == DW_TAG_lexical_block)
child_origin_die = corresponding_abstract_child;
/* According to DWARF3 3.3.8.2 #3 new entries without their abstract
counterpart may exist. */
if (child_origin_die != child_die)
{
if (child_die->tag != child_origin_die->tag
&& !(child_die->tag == DW_TAG_inlined_subroutine
&& child_origin_die->tag == DW_TAG_subprogram))
complaint (_("Child DIE %s and its abstract origin %s have "
"different tags"),
sect_offset_str (child_die->sect_off),
sect_offset_str (child_origin_die->sect_off));
if (child_origin_die->parent != origin_die)
complaint (_("Child DIE %s and its abstract origin %s have "
"different parents"),
sect_offset_str (child_die->sect_off),
sect_offset_str (child_origin_die->sect_off));
else
offsets.push_back (child_origin_die->sect_off);
}
if (are_isomorphic)
corresponding_abstract_child = corresponding_abstract_child->sibling;
}
if (!offsets.empty ())
{
std::sort (offsets.begin (), offsets.end ());
for (auto offsets_it = offsets.begin () + 1;
offsets_it < offsets.end ();
++offsets_it)
if (*(offsets_it - 1) == *offsets_it)
complaint (_("Multiple children of DIE %s refer "
"to DIE %s as their abstract origin"),
sect_offset_str (die->sect_off),
sect_offset_str (*offsets_it));
}
auto offsets_it = offsets.begin ();
die_info *origin_child_die = origin_die->child;
while (origin_child_die != nullptr && origin_child_die->tag != 0)
{
/* Is ORIGIN_CHILD_DIE referenced by any of the DIE children? */
while (offsets_it < offsets.end ()
&& *offsets_it < origin_child_die->sect_off)
++offsets_it;
if (offsets_it == offsets.end ()
|| *offsets_it > origin_child_die->sect_off)
{
/* Found that ORIGIN_CHILD_DIE is really not referenced.
Check whether we're already processing ORIGIN_CHILD_DIE.
This can happen with mutually referenced abstract_origins.
PR 16581. */
if (!origin_child_die->in_process)
process_die (origin_child_die, origin_cu);
}
origin_child_die = origin_child_die->sibling;
}
origin_cu->list_in_scope = origin_previous_list_in_scope;
if (cu != origin_cu)
compute_delayed_physnames (origin_cu);
}
/* Return TRUE if the given DIE is the program's "main". DWARF 4 has
defined a dedicated DW_AT_main_subprogram attribute to indicate the
starting function of the program, however with older versions the
DW_CC_program value of the DW_AT_calling_convention attribute was
used instead as the only means available. We handle both variants. */
static bool
dwarf2_func_is_main_p (struct die_info *die, struct dwarf2_cu *cu)
{
if (dwarf2_flag_true_p (die, DW_AT_main_subprogram, cu))
return true;
struct attribute *attr = dwarf2_attr (die, DW_AT_calling_convention, cu);
if (attr == nullptr)
return false;
std::optional<ULONGEST> value = attr->unsigned_constant ();
return value.has_value () && *value == DW_CC_program;
}
/* A helper to handle Ada's "Pragma Import" feature when it is applied
to a function. */
static bool
check_ada_pragma_import (struct die_info *die, struct dwarf2_cu *cu)
{
if (cu->lang () != language_ada)
return false;
/* A Pragma Import will have both a name and a linkage name. With a
newer version of GNAT, we have to examine the full name, because
the compiler might decide to emit a linkage name matching the
full name in some scenario. */
const char *name = dwarf2_full_name (nullptr, die, cu);
if (name == nullptr)
return false;
const char *linkage_name = dw2_linkage_name (die, cu);
/* Disallow the special Ada symbols. */
if (!is_ada_import_or_export (cu, name, linkage_name))
return false;
/* A Pragma Import will be a declaration, while a Pragma Export will
not be. */
if (!die_is_declaration (die, cu))
return false;
new_symbol (die, read_type_die (die, cu), cu);
return true;
}
/* Apply fixups to LOW_PC and HIGH_PC due to an incorrect DIE in CU. */
static void
fixup_low_high_pc (struct dwarf2_cu *cu, struct die_info *die, CORE_ADDR *low_pc,
CORE_ADDR *high_pc)
{
if (die->tag != DW_TAG_subprogram)
return;
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct gdbarch *gdbarch = objfile->arch ();
if (gdbarch_bfd_arch_info (gdbarch)->arch == bfd_arch_arm
&& cu->producer_is_gas_ge_2_39 ())
{
/* Gas version 2.39 produces DWARF for a Thumb subprogram with a low_pc
attribute with the thumb bit set (PR gas/31115). Work around this. */
*low_pc = gdbarch_addr_bits_remove (gdbarch, *low_pc);
if (high_pc != nullptr)
*high_pc = gdbarch_addr_bits_remove (gdbarch, *high_pc);
}
}
static void
read_func_scope (struct die_info *die, struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct gdbarch *gdbarch = objfile->arch ();
struct context_stack *newobj;
CORE_ADDR lowpc;
CORE_ADDR highpc;
struct die_info *child_die;
struct attribute *attr, *call_line, *call_file;
const char *name;
struct block *block;
int inlined_func = (die->tag == DW_TAG_inlined_subroutine);
std::vector<struct symbol *> template_args;
struct template_symbol *templ_func = NULL;
if (inlined_func)
{
/* If we do not have call site information, we can't show the
caller of this inlined function. That's too confusing, so
only use the scope for local variables. */
call_line = dwarf2_attr (die, DW_AT_call_line, cu);
call_file = dwarf2_attr (die, DW_AT_call_file, cu);
if (call_line == NULL || call_file == NULL)
{
read_lexical_block_scope (die, cu);
return;
}
}
name = dwarf2_name (die, cu);
if (name == nullptr)
name = dw2_linkage_name (die, cu);
/* Ignore functions with missing or empty names. These are actually
illegal according to the DWARF standard. */
if (name == NULL)
{
complaint (_("missing name for subprogram DIE at %s"),
sect_offset_str (die->sect_off));
return;
}
if (check_ada_pragma_import (die, cu))
{
/* We already made the symbol for the Pragma Import, and because
it is a declaration, we know it won't have any other
important information, so we can simply return. */
return;
}
/* Ignore functions with missing or invalid low and high pc attributes. */
unrelocated_addr unrel_low, unrel_high;
if (dwarf2_get_pc_bounds (die, &unrel_low, &unrel_high, cu, nullptr, nullptr)
<= PC_BOUNDS_INVALID)
{
if (have_complaint ())
{
attr = dwarf2_attr (die, DW_AT_external, cu);
bool external_p = attr != nullptr && attr->as_boolean ();
attr = dwarf2_attr (die, DW_AT_inline, cu);
bool inlined_p = false;
if (attr != nullptr)
{
std::optional<ULONGEST> value = attr->unsigned_constant ();
inlined_p = (value.has_value ()
&& (*value == DW_INL_inlined
|| *value == DW_INL_declared_inlined));
}
attr = dwarf2_attr (die, DW_AT_declaration, cu);
bool decl_p = attr != nullptr && attr->as_boolean ();
if (!external_p && !inlined_p && !decl_p)
complaint (_("cannot get low and high bounds "
"for subprogram DIE at %s"),
sect_offset_str (die->sect_off));
}
return;
}
lowpc = per_objfile->relocate (unrel_low);
highpc = per_objfile->relocate (unrel_high);
fixup_low_high_pc (cu, die, &lowpc, &highpc);
/* If we have any template arguments, then we must allocate a
different sort of symbol. */
for (child_die = die->child; child_die; child_die = child_die->sibling)
{
if (child_die->tag == DW_TAG_template_type_param
|| child_die->tag == DW_TAG_template_value_param)
{
templ_func = new (&objfile->objfile_obstack) template_symbol;
templ_func->subclass = SYMBOL_TEMPLATE;
break;
}
}
gdb_assert (cu->get_builder () != nullptr);
newobj = cu->get_builder ()->push_context (0, lowpc);
newobj->name = new_symbol (die, read_type_die (die, cu), cu, templ_func);
if (dwarf2_func_is_main_p (die, cu))
set_objfile_main_name (objfile, newobj->name->linkage_name (),
cu->lang ());
/* If there is a location expression for DW_AT_frame_base, record
it. */
attr = dwarf2_attr (die, DW_AT_frame_base, cu);
if (attr != nullptr)
dwarf2_symbol_mark_computed (attr, newobj->name, cu, 1);
/* If there is a location for the static link, record it. */
newobj->static_link = NULL;
attr = dwarf2_attr (die, DW_AT_static_link, cu);
if (attr != nullptr)
{
newobj->static_link
= XOBNEW (&objfile->objfile_obstack, struct dynamic_prop);
attr_to_dynamic_prop (attr, die, cu, newobj->static_link,
cu->addr_type ());
}
cu->list_in_scope = cu->get_builder ()->get_local_symbols ();
if (die->child != NULL)
{
child_die = die->child;
while (child_die && child_die->tag)
{
if (child_die->tag == DW_TAG_template_type_param
|| child_die->tag == DW_TAG_template_value_param)
{
struct symbol *arg = new_symbol (child_die, NULL, cu);
if (arg != NULL)
template_args.push_back (arg);
}
else
process_die (child_die, cu);
child_die = child_die->sibling;
}
}
inherit_abstract_dies (die, cu);
/* If we have a DW_AT_specification, we might need to import using
directives from the context of the specification DIE. See the
comment in determine_prefix. */
if (cu->lang () == language_cplus
&& dwarf2_attr (die, DW_AT_specification, cu))
{
struct dwarf2_cu *spec_cu = cu;
struct die_info *spec_die = die_specification (die, &spec_cu);
while (spec_die)
{
child_die = spec_die->child;
while (child_die && child_die->tag)
{
if (child_die->tag == DW_TAG_imported_module)
process_die (child_die, spec_cu);
child_die = child_die->sibling;
}
/* In some cases, GCC generates specification DIEs that
themselves contain DW_AT_specification attributes. */
spec_die = die_specification (spec_die, &spec_cu);
}
}
struct context_stack cstk = cu->get_builder ()->pop_context ();
/* Make a block for the local symbols within. */
block = cu->get_builder ()->finish_block (cstk.name, cstk.old_blocks,
cstk.static_link, lowpc, highpc);
/* For C++, set the block's scope. */
if ((cu->lang () == language_cplus
|| cu->lang () == language_fortran
|| cu->lang () == language_d
|| cu->lang () == language_rust)
&& cu->processing_has_namespace_info)
block->set_scope (determine_prefix (die, cu),
&objfile->objfile_obstack);
/* If we have address ranges, record them. */
dwarf2_record_block_ranges (die, block, cu);
gdbarch_make_symbol_special (gdbarch, cstk.name, objfile);
/* Attach template arguments to function. */
if (!template_args.empty ())
{
gdb_assert (templ_func != NULL);
templ_func->n_template_arguments = template_args.size ();
templ_func->template_arguments
= XOBNEWVEC (&objfile->objfile_obstack, struct symbol *,
templ_func->n_template_arguments);
memcpy (templ_func->template_arguments,
template_args.data (),
(templ_func->n_template_arguments * sizeof (struct symbol *)));
/* Make sure that the symtab is set on the new symbols. Even
though they don't appear in this symtab directly, other parts
of gdb assume that symbols do, and this is reasonably
true. */
for (symbol *sym : template_args)
sym->set_symtab (templ_func->symtab ());
}
/* In C++, we can have functions nested inside functions (e.g., when
a function declares a class that has methods). This means that
when we finish processing a function scope, we may need to go
back to building a containing block's symbol lists. */
*cu->get_builder ()->get_local_symbols () = cstk.locals;
cu->get_builder ()->set_local_using_directives (cstk.local_using_directives);
/* If we've finished processing a top-level function, subsequent
symbols go in the file symbol list. */
if (cu->get_builder ()->outermost_context_p ())
cu->list_in_scope = cu->get_builder ()->get_file_symbols ();
}
/* Process all the DIES contained within a lexical block scope. Start
a new scope, process the dies, and then close the scope. */
static void
read_lexical_block_scope (struct die_info *die, struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
CORE_ADDR lowpc, highpc;
struct die_info *child_die;
/* Ignore blocks with missing or invalid low and high pc attributes. */
/* ??? Perhaps consider discontiguous blocks defined by DW_AT_ranges
as multiple lexical blocks? Handling children in a sane way would
be nasty. Might be easier to properly extend generic blocks to
describe ranges. */
unrelocated_addr unrel_low, unrel_high;
switch (dwarf2_get_pc_bounds (die, &unrel_low, &unrel_high, cu,
nullptr, nullptr))
{
case PC_BOUNDS_NOT_PRESENT:
/* DW_TAG_lexical_block has no attributes, process its children as if
there was no wrapping by that DW_TAG_lexical_block.
GCC does no longer produces such DWARF since GCC r224161. */
for (child_die = die->child;
child_die != NULL && child_die->tag;
child_die = child_die->sibling)
{
/* We might already be processing this DIE. This can happen
in an unusual circumstance -- where a subroutine A
appears lexically in another subroutine B, but A actually
inlines B. The recursion is broken here, rather than in
inherit_abstract_dies, because it seems better to simply
drop concrete children here. */
if (!child_die->in_process)
process_die (child_die, cu);
}
return;
case PC_BOUNDS_INVALID:
return;
}
lowpc = per_objfile->relocate (unrel_low);
highpc = per_objfile->relocate (unrel_high);
cu->get_builder ()->push_context (0, lowpc);
if (die->child != NULL)
{
child_die = die->child;
while (child_die && child_die->tag)
{
process_die (child_die, cu);
child_die = child_die->sibling;
}
}
inherit_abstract_dies (die, cu);
struct context_stack cstk = cu->get_builder ()->pop_context ();
if (*cu->get_builder ()->get_local_symbols () != NULL
|| (*cu->get_builder ()->get_local_using_directives ()) != NULL)
{
struct block *block
= cu->get_builder ()->finish_block (0, cstk.old_blocks, NULL,
cstk.start_addr, highpc);
/* Note that recording ranges after traversing children, as we
do here, means that recording a parent's ranges entails
walking across all its children's ranges as they appear in
the address map, which is quadratic behavior.
It would be nicer to record the parent's ranges before
traversing its children, simply overriding whatever you find
there. But since we don't even decide whether to create a
block until after we've traversed its children, that's hard
to do. */
dwarf2_record_block_ranges (die, block, cu);
}
*cu->get_builder ()->get_local_symbols () = cstk.locals;
cu->get_builder ()->set_local_using_directives (cstk.local_using_directives);
}
static void dwarf2_ranges_read_low_addrs
(unsigned offset,
struct dwarf2_cu *cu,
dwarf_tag tag,
std::vector<unrelocated_addr> &result);
/* Read in DW_TAG_call_site and insert it to CU->call_site_htab. */
static void
read_call_site_scope (struct die_info *die, struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct gdbarch *gdbarch = objfile->arch ();
struct attribute *attr;
int nparams;
struct die_info *child_die;
attr = dwarf2_attr (die, DW_AT_call_return_pc, cu);
if (attr == NULL)
{
/* This was a pre-DWARF-5 GNU extension alias
for DW_AT_call_return_pc. */
attr = dwarf2_attr (die, DW_AT_low_pc, cu);
}
if (!attr)
{
complaint (_("missing DW_AT_call_return_pc for DW_TAG_call_site "
"DIE %s [in module %s]"),
sect_offset_str (die->sect_off), objfile_name (objfile));
return;
}
unrelocated_addr pc = attr->as_address ();
/* Count parameters at the caller. */
nparams = 0;
for (child_die = die->child; child_die && child_die->tag;
child_die = child_die->sibling)
{
if (child_die->tag != DW_TAG_call_site_parameter
&& child_die->tag != DW_TAG_GNU_call_site_parameter)
{
complaint (_("Tag %d is not DW_TAG_call_site_parameter in "
"DW_TAG_call_site child DIE %s [in module %s]"),
child_die->tag, sect_offset_str (child_die->sect_off),
objfile_name (objfile));
continue;
}
nparams++;
}
struct call_site *call_site
= new (XOBNEWVAR (&objfile->objfile_obstack,
struct call_site,
sizeof (*call_site) + sizeof (call_site->parameter[0]) * nparams))
struct call_site (pc, cu->per_cu, per_objfile);
if (!cu->call_site_htab.emplace (call_site).second)
{
complaint (_("Duplicate PC %s for DW_TAG_call_site "
"DIE %s [in module %s]"),
paddress (gdbarch, (CORE_ADDR) pc), sect_offset_str (die->sect_off),
objfile_name (objfile));
return;
}
/* We never call the destructor of call_site, so we must ensure it is
trivially destructible. */
static_assert(std::is_trivially_destructible<struct call_site>::value);
if (dwarf2_flag_true_p (die, DW_AT_call_tail_call, cu)
|| dwarf2_flag_true_p (die, DW_AT_GNU_tail_call, cu))
{
struct die_info *func_die;
/* Skip also over DW_TAG_inlined_subroutine. */
for (func_die = die->parent;
func_die && func_die->tag != DW_TAG_subprogram
&& func_die->tag != DW_TAG_subroutine_type;
func_die = func_die->parent);
/* DW_AT_call_all_calls is a superset
of DW_AT_call_all_tail_calls. */
if (func_die
&& !dwarf2_flag_true_p (func_die, DW_AT_call_all_calls, cu)
&& !dwarf2_flag_true_p (func_die, DW_AT_GNU_all_call_sites, cu)
&& !dwarf2_flag_true_p (func_die, DW_AT_call_all_tail_calls, cu)
&& !dwarf2_flag_true_p (func_die, DW_AT_GNU_all_tail_call_sites, cu))
{
/* TYPE_TAIL_CALL_LIST is not interesting in functions where it is
not complete. But keep CALL_SITE for look ups via call_site_htab,
both the initial caller containing the real return address PC and
the final callee containing the current PC of a chain of tail
calls do not need to have the tail call list complete. But any
function candidate for a virtual tail call frame searched via
TYPE_TAIL_CALL_LIST must have the tail call list complete to be
determined unambiguously. */
}
else
{
struct type *func_type = NULL;
if (func_die)
func_type = get_die_type (func_die, cu);
if (func_type != NULL)
{
gdb_assert (func_type->code () == TYPE_CODE_FUNC);
/* Enlist this call site to the function. */
call_site->tail_call_next = TYPE_TAIL_CALL_LIST (func_type);
TYPE_TAIL_CALL_LIST (func_type) = call_site;
}
else
complaint (_("Cannot find function owning DW_TAG_call_site "
"DIE %s [in module %s]"),
sect_offset_str (die->sect_off), objfile_name (objfile));
}
}
attr = dwarf2_attr (die, DW_AT_call_target, cu);
if (attr == NULL)
attr = dwarf2_attr (die, DW_AT_GNU_call_site_target, cu);
if (attr == NULL)
attr = dwarf2_attr (die, DW_AT_call_origin, cu);
if (attr == NULL)
{
/* This was a pre-DWARF-5 GNU extension alias for DW_AT_call_origin. */
attr = dwarf2_attr (die, DW_AT_abstract_origin, cu);
}
call_site->target.set_loc_dwarf_block (nullptr);
if (!attr || (attr->form_is_block () && attr->as_block ()->size == 0))
/* Keep NULL DWARF_BLOCK. */;
else if (attr->form_is_block ())
{
struct dwarf2_locexpr_baton *dlbaton;
struct dwarf_block *block = attr->as_block ();
dlbaton = XOBNEW (&objfile->objfile_obstack, struct dwarf2_locexpr_baton);
dlbaton->data = block->data;
dlbaton->size = block->size;
dlbaton->per_objfile = per_objfile;
dlbaton->per_cu = cu->per_cu;
call_site->target.set_loc_dwarf_block (dlbaton);
}
else if (attr->form_is_ref ())
{
struct dwarf2_cu *target_cu = cu;
struct die_info *target_die;
target_die = follow_die_ref (die, attr, &target_cu);
gdb_assert (target_cu->per_objfile->objfile == objfile);
struct attribute *ranges_attr
= dwarf2_attr (target_die, DW_AT_ranges, target_cu);
if (die_is_declaration (target_die, target_cu))
{
const char *target_physname;
/* Prefer the mangled name; otherwise compute the demangled one. */
target_physname = dw2_linkage_name (target_die, target_cu);
if (target_physname == NULL)
target_physname = dwarf2_physname (NULL, target_die, target_cu);
if (target_physname == NULL)
complaint (_("DW_AT_call_target target DIE has invalid "
"physname, for referencing DIE %s [in module %s]"),
sect_offset_str (die->sect_off), objfile_name (objfile));
else
call_site->target.set_loc_physname (target_physname);
}
else if (ranges_attr != nullptr && ranges_attr->form_is_unsigned ())
{
ULONGEST ranges_offset = (ranges_attr->as_unsigned ()
+ target_cu->gnu_ranges_base);
std::vector<unrelocated_addr> addresses;
dwarf2_ranges_read_low_addrs (ranges_offset, target_cu,
target_die->tag, addresses);
unrelocated_addr *saved = XOBNEWVEC (&objfile->objfile_obstack,
unrelocated_addr,
addresses.size ());
std::copy (addresses.begin (), addresses.end (), saved);
call_site->target.set_loc_array (addresses.size (), saved);
}
else
{
unrelocated_addr lowpc;
/* DW_AT_entry_pc should be preferred. */
if (dwarf2_get_pc_bounds (target_die, &lowpc, NULL, target_cu,
nullptr, nullptr)
<= PC_BOUNDS_INVALID)
complaint (_("DW_AT_call_target target DIE has invalid "
"low pc, for referencing DIE %s [in module %s]"),
sect_offset_str (die->sect_off), objfile_name (objfile));
else
call_site->target.set_loc_physaddr (lowpc);
}
}
else
complaint (_("DW_TAG_call_site DW_AT_call_target is neither "
"block nor reference, for DIE %s [in module %s]"),
sect_offset_str (die->sect_off), objfile_name (objfile));
for (child_die = die->child;
child_die && child_die->tag;
child_die = child_die->sibling)
{
struct call_site_parameter *parameter;
struct attribute *loc, *origin;
if (child_die->tag != DW_TAG_call_site_parameter
&& child_die->tag != DW_TAG_GNU_call_site_parameter)
{
/* Already printed the complaint above. */
continue;
}
gdb_assert (call_site->parameter_count < nparams);
parameter = &call_site->parameter[call_site->parameter_count];
/* DW_AT_location specifies the register number or DW_AT_abstract_origin
specifies DW_TAG_formal_parameter. Value of the data assumed for the
register is contained in DW_AT_call_value. */
loc = dwarf2_attr (child_die, DW_AT_location, cu);
origin = dwarf2_attr (child_die, DW_AT_call_parameter, cu);
if (origin == NULL)
{
/* This was a pre-DWARF-5 GNU extension alias
for DW_AT_call_parameter. */
origin = dwarf2_attr (child_die, DW_AT_abstract_origin, cu);
}
if (loc == NULL && origin != NULL && origin->form_is_ref ())
{
parameter->kind = CALL_SITE_PARAMETER_PARAM_OFFSET;
sect_offset sect_off = origin->get_ref_die_offset ();
if (!cu->header.offset_in_cu_p (sect_off))
{
/* As DW_OP_GNU_parameter_ref uses CU-relative offset this
binding can be done only inside one CU. Such referenced DIE
therefore cannot be even moved to DW_TAG_partial_unit. */
complaint (_("DW_AT_call_parameter offset is not in CU for "
"DW_TAG_call_site child DIE %s [in module %s]"),
sect_offset_str (child_die->sect_off),
objfile_name (objfile));
continue;
}
parameter->u.param_cu_off
= (cu_offset) (sect_off - cu->header.sect_off);
}
else if (loc == NULL || origin != NULL || !loc->form_is_block ())
{
complaint (_("No DW_FORM_block* DW_AT_location for "
"DW_TAG_call_site child DIE %s [in module %s]"),
sect_offset_str (child_die->sect_off), objfile_name (objfile));
continue;
}
else
{
struct dwarf_block *block = loc->as_block ();
parameter->u.dwarf_reg = dwarf_block_to_dwarf_reg
(block->data, &block->data[block->size]);
if (parameter->u.dwarf_reg != -1)
parameter->kind = CALL_SITE_PARAMETER_DWARF_REG;
else if (dwarf_block_to_sp_offset (gdbarch, block->data,
&block->data[block->size],
&parameter->u.fb_offset))
parameter->kind = CALL_SITE_PARAMETER_FB_OFFSET;
else
{
complaint (_("Only single DW_OP_reg or DW_OP_fbreg is supported "
"for DW_FORM_block* DW_AT_location is supported for "
"DW_TAG_call_site child DIE %s "
"[in module %s]"),
sect_offset_str (child_die->sect_off),
objfile_name (objfile));
continue;
}
}
attr = dwarf2_attr (child_die, DW_AT_call_value, cu);
if (attr == NULL)
attr = dwarf2_attr (child_die, DW_AT_GNU_call_site_value, cu);
if (attr == NULL || !attr->form_is_block ())
{
complaint (_("No DW_FORM_block* DW_AT_call_value for "
"DW_TAG_call_site child DIE %s [in module %s]"),
sect_offset_str (child_die->sect_off),
objfile_name (objfile));
continue;
}
struct dwarf_block *block = attr->as_block ();
parameter->value = block->data;
parameter->value_size = block->size;
/* Parameters are not pre-cleared by memset above. */
parameter->data_value = NULL;
parameter->data_value_size = 0;
call_site->parameter_count++;
attr = dwarf2_attr (child_die, DW_AT_call_data_value, cu);
if (attr == NULL)
attr = dwarf2_attr (child_die, DW_AT_GNU_call_site_data_value, cu);
if (attr != nullptr)
{
if (!attr->form_is_block ())
complaint (_("No DW_FORM_block* DW_AT_call_data_value for "
"DW_TAG_call_site child DIE %s [in module %s]"),
sect_offset_str (child_die->sect_off),
objfile_name (objfile));
else
{
block = attr->as_block ();
parameter->data_value = block->data;
parameter->data_value_size = block->size;
}
}
}
}
/* Helper function for read_variable. If DIE represents a virtual
table, then return the type of the concrete object that is
associated with the virtual table. Otherwise, return NULL. */
static struct type *
rust_containing_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr = dwarf2_attr (die, DW_AT_type, cu);
if (attr == NULL)
return NULL;
/* Find the type DIE. */
struct die_info *type_die = NULL;
struct dwarf2_cu *type_cu = cu;
if (attr->form_is_ref ())
type_die = follow_die_ref (die, attr, &type_cu);
if (type_die == NULL)
return NULL;
if (dwarf2_attr (type_die, DW_AT_containing_type, type_cu) == NULL)
return NULL;
return die_containing_type (type_die, type_cu);
}
/* Read a variable (DW_TAG_variable) DIE and create a new symbol. */
static void
read_variable (struct die_info *die, struct dwarf2_cu *cu)
{
struct rust_vtable_symbol *storage = NULL;
if (cu->lang () == language_rust)
{
struct type *containing_type = rust_containing_type (die, cu);
if (containing_type != NULL)
{
struct objfile *objfile = cu->per_objfile->objfile;
storage = new (&objfile->objfile_obstack) rust_vtable_symbol;
storage->concrete_type = containing_type;
storage->subclass = SYMBOL_RUST_VTABLE;
}
}
struct symbol *res = new_symbol (die, NULL, cu, storage);
struct attribute *abstract_origin
= dwarf2_attr (die, DW_AT_abstract_origin, cu);
struct attribute *loc = dwarf2_attr (die, DW_AT_location, cu);
if (res == NULL && loc && abstract_origin)
{
/* We have a variable without a name, but with a location and an abstract
origin. This may be a concrete instance of an abstract variable
referenced from an DW_OP_GNU_variable_value, so save it to find it back
later. */
struct dwarf2_cu *origin_cu = cu;
struct die_info *origin_die
= follow_die_ref (die, abstract_origin, &origin_cu);
dwarf2_per_objfile *per_objfile = cu->per_objfile;
per_objfile->per_bfd->abstract_to_concrete
[origin_die->sect_off].push_back (die->sect_off);
}
}
/* Call CALLBACK from DW_AT_ranges attribute value OFFSET
reading .debug_rnglists.
Callback's type should be:
void (CORE_ADDR range_beginning, CORE_ADDR range_end)
Return true if the attributes are present and valid, otherwise,
return false. */
template <typename Callback>
static bool
dwarf2_rnglists_process (unsigned offset, struct dwarf2_cu *cu,
dwarf_tag tag, Callback &&callback)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
bfd *obfd = objfile->obfd.get ();
/* Base address selection entry. */
std::optional<unrelocated_addr> base;
const gdb_byte *buffer;
bool overflow = false;
ULONGEST addr_index;
struct dwarf2_section_info *rnglists_section;
base = cu->base_address;
rnglists_section = cu_debug_rnglists_section (cu, tag);
rnglists_section->read (objfile);
if (offset >= rnglists_section->size)
{
complaint (_("Offset %d out of bounds for DW_AT_ranges attribute"),
offset);
return false;
}
buffer = rnglists_section->buffer + offset;
while (1)
{
/* Initialize it due to a false compiler warning. */
unrelocated_addr range_beginning = {}, range_end = {};
const gdb_byte *buf_end = (rnglists_section->buffer
+ rnglists_section->size);
unsigned int bytes_read;
if (buffer == buf_end)
{
overflow = true;
break;
}
const auto rlet = static_cast<enum dwarf_range_list_entry>(*buffer++);
switch (rlet)
{
case DW_RLE_end_of_list:
break;
case DW_RLE_base_address:
if (buffer + cu->header.addr_size > buf_end)
{
overflow = true;
break;
}
base = cu->header.read_address (obfd, buffer, &bytes_read);
buffer += bytes_read;
break;
case DW_RLE_base_addressx:
addr_index = read_unsigned_leb128 (obfd, buffer, &bytes_read);
buffer += bytes_read;
base = read_addr_index (cu, addr_index);
break;
case DW_RLE_start_length:
if (buffer + cu->header.addr_size > buf_end)
{
overflow = true;
break;
}
range_beginning = cu->header.read_address (obfd, buffer,
&bytes_read);
buffer += bytes_read;
range_end
= (unrelocated_addr) ((CORE_ADDR) range_beginning
+ read_unsigned_leb128 (obfd, buffer,
&bytes_read));
buffer += bytes_read;
if (buffer > buf_end)
{
overflow = true;
break;
}
break;
case DW_RLE_startx_length:
addr_index = read_unsigned_leb128 (obfd, buffer, &bytes_read);
buffer += bytes_read;
range_beginning = read_addr_index (cu, addr_index);
if (buffer > buf_end)
{
overflow = true;
break;
}
range_end
= (unrelocated_addr) ((CORE_ADDR) range_beginning
+ read_unsigned_leb128 (obfd, buffer,
&bytes_read));
buffer += bytes_read;
break;
case DW_RLE_offset_pair:
range_beginning = (unrelocated_addr) read_unsigned_leb128 (obfd, buffer,
&bytes_read);
buffer += bytes_read;
if (buffer > buf_end)
{
overflow = true;
break;
}
range_end = (unrelocated_addr) read_unsigned_leb128 (obfd, buffer,
&bytes_read);
buffer += bytes_read;
if (buffer > buf_end)
{
overflow = true;
break;
}
break;
case DW_RLE_start_end:
if (buffer + 2 * cu->header.addr_size > buf_end)
{
overflow = true;
break;
}
range_beginning = cu->header.read_address (obfd, buffer,
&bytes_read);
buffer += bytes_read;
range_end = cu->header.read_address (obfd, buffer, &bytes_read);
buffer += bytes_read;
break;
case DW_RLE_startx_endx:
addr_index = read_unsigned_leb128 (obfd, buffer, &bytes_read);
buffer += bytes_read;
range_beginning = read_addr_index (cu, addr_index);
if (buffer > buf_end)
{
overflow = true;
break;
}
addr_index = read_unsigned_leb128 (obfd, buffer, &bytes_read);
buffer += bytes_read;
range_end = read_addr_index (cu, addr_index);
break;
default:
complaint (_("Invalid .debug_rnglists data (no base address)"));
return false;
}
if (rlet == DW_RLE_end_of_list || overflow)
break;
if (rlet == DW_RLE_base_address)
continue;
if (range_beginning > range_end)
{
/* Inverted range entries are invalid. */
complaint (_("Invalid .debug_rnglists data (inverted range)"));
return false;
}
/* Empty range entries have no effect. */
if (range_beginning == range_end)
continue;
/* Only DW_RLE_offset_pair needs the base address added. */
if (rlet == DW_RLE_offset_pair)
{
if (!base.has_value ())
{
/* We have no valid base address for the DW_RLE_offset_pair. */
complaint (_("Invalid .debug_rnglists data (no base address for "
"DW_RLE_offset_pair)"));
return false;
}
range_beginning = (unrelocated_addr) ((CORE_ADDR) range_beginning
+ (CORE_ADDR) *base);
range_end = (unrelocated_addr) ((CORE_ADDR) range_end
+ (CORE_ADDR) *base);
}
/* A not-uncommon case of bad debug info.
Don't pollute the addrmap with bad data. */
if (range_beginning == (unrelocated_addr) 0
&& !per_objfile->per_bfd->has_section_at_zero)
{
complaint (_(".debug_rnglists entry has start address of zero"
" [in module %s]"), objfile_name (objfile));
continue;
}
callback (range_beginning, range_end);
}
if (overflow)
{
complaint (_("Offset %d is not terminated "
"for DW_AT_ranges attribute"),
offset);
return false;
}
return true;
}
/* Call CALLBACK from DW_AT_ranges attribute value OFFSET reading .debug_ranges.
Callback's type should be:
void (unrelocated_addr range_beginning, unrelocated_addr range_end)
Return 1 if the attributes are present and valid, otherwise, return 0. */
template <typename Callback>
static int
dwarf2_ranges_process (unsigned offset, struct dwarf2_cu *cu, dwarf_tag tag,
Callback &&callback)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct comp_unit_head *cu_header = &cu->header;
bfd *obfd = objfile->obfd.get ();
unsigned int addr_size = cu_header->addr_size;
CORE_ADDR mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1));
/* Base address selection entry. */
std::optional<unrelocated_addr> base;
unsigned int dummy;
const gdb_byte *buffer;
if (cu_header->version >= 5)
return dwarf2_rnglists_process (offset, cu, tag, callback);
base = cu->base_address;
per_objfile->per_bfd->ranges.read (objfile);
if (offset >= per_objfile->per_bfd->ranges.size)
{
complaint (_("Offset %d out of bounds for DW_AT_ranges attribute"),
offset);
return 0;
}
buffer = per_objfile->per_bfd->ranges.buffer + offset;
while (1)
{
unrelocated_addr range_beginning, range_end;
range_beginning = cu->header.read_address (obfd, buffer, &dummy);
buffer += addr_size;
range_end = cu->header.read_address (obfd, buffer, &dummy);
buffer += addr_size;
offset += 2 * addr_size;
/* An end of list marker is a pair of zero addresses. */
if (range_beginning == (unrelocated_addr) 0
&& range_end == (unrelocated_addr) 0)
/* Found the end of list entry. */
break;
/* Each base address selection entry is a pair of 2 values.
The first is the largest possible address, the second is
the base address. Check for a base address here. */
if (((CORE_ADDR) range_beginning & mask) == mask)
{
/* If we found the largest possible address, then we already
have the base address in range_end. */
base = range_end;
continue;
}
if (!base.has_value ())
{
/* We have no valid base address for the ranges
data. */
complaint (_("Invalid .debug_ranges data (no base address)"));
return 0;
}
if (range_beginning > range_end)
{
/* Inverted range entries are invalid. */
complaint (_("Invalid .debug_ranges data (inverted range)"));
return 0;
}
/* Empty range entries have no effect. */
if (range_beginning == range_end)
continue;
range_beginning = (unrelocated_addr) ((CORE_ADDR) range_beginning
+ (CORE_ADDR) *base);
range_end = (unrelocated_addr) ((CORE_ADDR) range_end
+ (CORE_ADDR) *base);
/* A not-uncommon case of bad debug info.
Don't pollute the addrmap with bad data. */
if (range_beginning == (unrelocated_addr) 0
&& !per_objfile->per_bfd->has_section_at_zero)
{
complaint (_(".debug_ranges entry has start address of zero"
" [in module %s]"), objfile_name (objfile));
continue;
}
callback (range_beginning, range_end);
}
return 1;
}
/* See read.h. */
int
dwarf2_ranges_read (unsigned offset, unrelocated_addr *low_return,
unrelocated_addr *high_return, struct dwarf2_cu *cu,
addrmap_mutable *map, void *datum, dwarf_tag tag)
{
int low_set = 0;
unrelocated_addr low = {};
unrelocated_addr high = {};
int retval;
retval = dwarf2_ranges_process (offset, cu, tag,
[&] (unrelocated_addr range_beginning, unrelocated_addr range_end)
{
if (map != nullptr)
{
/* addrmap only accepts CORE_ADDR, so we must cast here. */
map->set_empty ((CORE_ADDR) range_beginning,
(CORE_ADDR) range_end - 1,
datum);
}
/* FIXME: This is recording everything as a low-high
segment of consecutive addresses. We should have a
data structure for discontiguous block ranges
instead. */
if (! low_set)
{
low = range_beginning;
high = range_end;
low_set = 1;
}
else
{
if (range_beginning < low)
low = range_beginning;
if (range_end > high)
high = range_end;
}
});
if (!retval)
return 0;
if (! low_set)
/* If the first entry is an end-of-list marker, the range
describes an empty scope, i.e. no instructions. */
return 0;
if (low_return)
*low_return = low;
if (high_return)
*high_return = high;
return 1;
}
/* Process ranges and fill in a vector of the low PC values only. */
static void
dwarf2_ranges_read_low_addrs (unsigned offset, struct dwarf2_cu *cu,
dwarf_tag tag,
std::vector<unrelocated_addr> &result)
{
dwarf2_ranges_process (offset, cu, tag,
[&] (unrelocated_addr start, unrelocated_addr end)
{
result.push_back (start);
});
}
/* Determine the low and high pc of a DW_TAG_entry_point. */
static pc_bounds_kind
dwarf2_get_pc_bounds_entry_point (die_info *die, unrelocated_addr *low,
unrelocated_addr *high, dwarf2_cu *cu)
{
gdb_assert (low != nullptr);
gdb_assert (high != nullptr);
if (die->parent->tag != DW_TAG_subprogram)
{
complaint (_("DW_TAG_entry_point not embedded in DW_TAG_subprogram"));
return PC_BOUNDS_INVALID;
}
/* A DW_TAG_entry_point is embedded in an subprogram. Therefore, we can use
the highpc from its enveloping subprogram and get the lowpc from
DWARF. */
const enum pc_bounds_kind bounds_kind = dwarf2_get_pc_bounds (die->parent,
low, high,
cu, nullptr,
nullptr);
if (bounds_kind == PC_BOUNDS_INVALID || bounds_kind == PC_BOUNDS_NOT_PRESENT)
return bounds_kind;
attribute *attr_low = dwarf2_attr (die, DW_AT_low_pc, cu);
if (!attr_low)
{
complaint (_("DW_TAG_entry_point is missing DW_AT_low_pc"));
return PC_BOUNDS_INVALID;
}
*low = attr_low->as_address ();
return bounds_kind;
}
/* Determine the low and high pc using the DW_AT_low_pc and DW_AT_high_pc or
DW_AT_ranges attributes of a DIE. */
static pc_bounds_kind
dwarf_get_pc_bounds_ranges_or_highlow_pc (die_info *die, unrelocated_addr *low,
unrelocated_addr *high, dwarf2_cu *cu,
addrmap_mutable *map, void *datum)
{
gdb_assert (low != nullptr);
gdb_assert (high != nullptr);
struct attribute *attr;
struct attribute *attr_high;
enum pc_bounds_kind ret;
attr_high = dwarf2_attr (die, DW_AT_high_pc, cu);
if (attr_high)
{
attr = dwarf2_attr (die, DW_AT_low_pc, cu);
if (attr != nullptr)
{
*low = attr->as_address ();
*high = attr_high->as_address ();
if (cu->header.version >= 4 && attr_high->form_is_constant ())
*high = (unrelocated_addr) ((ULONGEST) *high + (ULONGEST) *low);
/* Found consecutive range of addresses. */
ret = PC_BOUNDS_HIGH_LOW;
}
else
{
/* Found high w/o low attribute. */
ret = PC_BOUNDS_INVALID;
}
}
else
{
attr = dwarf2_attr (die, DW_AT_ranges, cu);
if (attr != nullptr && attr->form_is_unsigned ())
{
/* Offset in the .debug_ranges or .debug_rnglist section (depending
on DWARF version). */
ULONGEST ranges_offset = attr->as_unsigned ();
/* See dwarf2_cu::gnu_ranges_base's doc for why we might want to add
this value. */
if (die->tag != DW_TAG_compile_unit)
ranges_offset += cu->gnu_ranges_base;
/* Value of the DW_AT_ranges attribute is the offset in the
.debug_ranges section. */
if (!dwarf2_ranges_read (ranges_offset, low, high, cu,
map, datum, die->tag))
return PC_BOUNDS_INVALID;
/* Found discontinuous range of addresses. */
ret = PC_BOUNDS_RANGES;
}
else
{
/* Could not find high_pc or ranges attributed and thus no bounds
pair. */
ret = PC_BOUNDS_NOT_PRESENT;
}
}
return ret;
}
/* See read.h. */
pc_bounds_kind
dwarf2_get_pc_bounds (struct die_info *die, unrelocated_addr *lowpc,
unrelocated_addr *highpc, struct dwarf2_cu *cu,
addrmap_mutable *map, void *datum)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
unrelocated_addr low = {};
unrelocated_addr high = {};
enum pc_bounds_kind ret;
if (die->tag == DW_TAG_entry_point)
ret = dwarf2_get_pc_bounds_entry_point (die, &low, &high, cu);
else
ret = dwarf_get_pc_bounds_ranges_or_highlow_pc (die, &low, &high, cu, map,
datum);
if (ret == PC_BOUNDS_NOT_PRESENT || ret == PC_BOUNDS_INVALID)
return ret;
/* partial_die_info::read has also the strict LOW < HIGH requirement. */
if (high <= low)
return PC_BOUNDS_INVALID;
/* When using the GNU linker, .gnu.linkonce. sections are used to
eliminate duplicate copies of functions and vtables and such.
The linker will arbitrarily choose one and discard the others.
The AT_*_pc values for such functions refer to local labels in
these sections. If the section from that file was discarded, the
labels are not in the output, so the relocs get a value of 0.
If this is a discarded function, mark the pc bounds as invalid,
so that GDB will ignore it. */
if (low == (unrelocated_addr) 0
&& !per_objfile->per_bfd->has_section_at_zero)
return PC_BOUNDS_INVALID;
gdb_assert (lowpc != nullptr);
*lowpc = low;
if (highpc != nullptr)
*highpc = high;
return ret;
}
/* Assuming that DIE represents a subprogram DIE or a lexical block, get
its low and high PC addresses. Do nothing if these addresses could not
be determined. Otherwise, set LOWPC to the low address if it is smaller,
and HIGHPC to the high address if greater than HIGHPC. */
static void
dwarf2_get_subprogram_pc_bounds (struct die_info *die,
unrelocated_addr *lowpc,
unrelocated_addr *highpc,
struct dwarf2_cu *cu)
{
unrelocated_addr low, high;
struct die_info *child = die->child;
if (dwarf2_get_pc_bounds (die, &low, &high, cu, nullptr, nullptr)
>= PC_BOUNDS_RANGES)
{
*lowpc = std::min (*lowpc, low);
*highpc = std::max (*highpc, high);
}
/* If the language does not allow nested subprograms (either inside
subprograms or lexical blocks), we're done. */
if (cu->lang () != language_ada)
return;
/* Check all the children of the given DIE. If it contains nested
subprograms, then check their pc bounds. Likewise, we need to
check lexical blocks as well, as they may also contain subprogram
definitions. */
while (child && child->tag)
{
if (child->tag == DW_TAG_subprogram
|| child->tag == DW_TAG_lexical_block)
dwarf2_get_subprogram_pc_bounds (child, lowpc, highpc, cu);
child = child->sibling;
}
}
/* Get the low and high pc's represented by the scope DIE, and store
them in *LOWPC and *HIGHPC. If the correct values can't be
determined, set *LOWPC to -1 and *HIGHPC to 0. */
static void
get_scope_pc_bounds (struct die_info *die,
unrelocated_addr *lowpc, unrelocated_addr *highpc,
struct dwarf2_cu *cu)
{
unrelocated_addr best_low = (unrelocated_addr) -1;
unrelocated_addr best_high = {};
unrelocated_addr current_low, current_high;
if (dwarf2_get_pc_bounds (die, &current_low, &current_high, cu,
nullptr, nullptr)
>= PC_BOUNDS_RANGES)
{
best_low = current_low;
best_high = current_high;
}
else
{
struct die_info *child = die->child;
while (child && child->tag)
{
switch (child->tag) {
case DW_TAG_subprogram:
dwarf2_get_subprogram_pc_bounds (child, &best_low, &best_high, cu);
break;
case DW_TAG_namespace:
case DW_TAG_module:
/* FIXME: carlton/2004-01-16: Should we do this for
DW_TAG_class_type/DW_TAG_structure_type, too? I think
that current GCC's always emit the DIEs corresponding
to definitions of methods of classes as children of a
DW_TAG_compile_unit or DW_TAG_namespace (as opposed to
the DIEs giving the declarations, which could be
anywhere). But I don't see any reason why the
standards says that they have to be there. */
get_scope_pc_bounds (child, &current_low, &current_high, cu);
if (current_low != ((unrelocated_addr) -1))
{
best_low = std::min (best_low, current_low);
best_high = std::max (best_high, current_high);
}
break;
default:
/* Ignore. */
break;
}
child = child->sibling;
}
}
*lowpc = best_low;
*highpc = best_high;
}
/* Return the base address for DIE (which is represented by BLOCK) within
CU. The base address is the DW_AT_low_pc, or if that is not present,
the first address in the first range defined by DW_AT_ranges.
The DWARF standard actually says that if DIE has neither DW_AT_low_pc or
DW_AT_ranges then we should search in the parent of DIE for those
properties, and so on up the hierarchy, until we find a die with one of
those attributes, and use that as the base address. We don't implement
that yet simply because we've never encountered a need for it. */
static std::optional<CORE_ADDR>
dwarf2_die_base_address (struct die_info *die, struct block *block,
struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct attribute *attr = dwarf2_attr (die, DW_AT_low_pc, cu);
if (attr != nullptr)
{
CORE_ADDR res = per_objfile->relocate (attr->as_address ());
fixup_low_high_pc (cu, die, &res, nullptr);
return res;
}
else if (block->ranges ().size () > 0)
return block->ranges ()[0].start ();
return {};
}
/* Return true if ADDR is within any of the ranges covered by BLOCK. If
there are no sub-ranges then just check against the block's start and
end addresses, otherwise, check each sub-range covered by the block. */
static bool
dwarf2_addr_in_block_ranges (CORE_ADDR addr, struct block *block)
{
if (block->ranges ().size () == 0)
return addr >= block->start () && addr < block->end ();
/* Check if ADDR is within any of the block's sub-ranges. */
for (const blockrange &br : block->ranges ())
{
if (addr >= br.start () && addr < br.end ())
return true;
}
/* ADDR is not within any of the block's sub-ranges. */
return false;
}
/* Set the entry PC for BLOCK which represents DIE from CU. Relies on the
range information (if present) already having been read from DIE and
stored into BLOCK. */
static void
dwarf2_record_block_entry_pc (struct die_info *die, struct block *block,
struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
/* Filled with the entry-pc if we can find it. */
std::optional<CORE_ADDR> entry;
/* Set the block's entry PC where possible. */
struct attribute *attr = dwarf2_attr (die, DW_AT_entry_pc, cu);
if (attr != nullptr)
{
/* DWARF-5 allows for the DW_AT_entry_pc to be an unsigned constant
offset from the containing DIE's base address. We don't limit the
constant handling to DWARF-5 though. If a broken compiler emits
this for DWARF-4 then we handle it just as we would for DWARF-5. */
if (attr->form_is_constant ())
{
if (attr->form_is_unsigned ())
{
CORE_ADDR offset = attr->as_unsigned ();
std::optional<CORE_ADDR> base
= dwarf2_die_base_address (die, block, cu);
if (base.has_value ())
entry.emplace (base.value () + offset);
}
else
{
/* We could possibly handle signed constants, but this is out
of spec, so for now, just complain and ignore it. */
complaint (_("Invalid form for DW_AT_entry_pc: %s"),
dwarf_form_name (attr->form));
}
}
else
entry.emplace (per_objfile->relocate (attr->as_address ()));
}
else
entry = dwarf2_die_base_address (die, block, cu);
if (entry.has_value ())
{
CORE_ADDR entry_pc = entry.value ();
/* Some compilers (e.g. GCC) will have the DW_AT_entry_pc point at an
empty sub-range, which by a strict reading of the DWARF means that
the entry-pc is outside the blocks code range. If we continue
using this address then GDB will confuse itself, breakpoints will
be placed at the entry-pc, but once stopped there, GDB will not
recognise that it is inside this block.
To avoid this, ignore entry-pc values that are outside the block's
range, GDB will then select a suitable default entry-pc. */
if (dwarf2_addr_in_block_ranges (entry_pc, block))
block->set_entry_pc (entry_pc);
else
complaint (_("in %s, DIE %s, DW_AT_entry_pc (%s) outside "
"block range (%s -> %s)"),
objfile_name (per_objfile->objfile),
sect_offset_str (die->sect_off),
paddress (per_objfile->objfile->arch (), entry_pc),
paddress (per_objfile->objfile->arch (), block->start ()),
paddress (per_objfile->objfile->arch (), block->end ()));
}
}
/* Record the address ranges for BLOCK, offset by BASEADDR, as given
in DIE. Also set the entry PC for BLOCK. */
static void
dwarf2_record_block_ranges (struct die_info *die, struct block *block,
struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct attribute *attr;
struct attribute *attr_high;
/* Like dwarf_get_pc_bounds_ranges_or_highlow_pc, we read either the
low/high pc attributes, OR the ranges attribute, but not both. If we
parse both here then we open up the possibility that, due to invalid
DWARF, a block's start() and end() might not contain all of the ranges.
We have seen this in the wild with older (pre v9) versions of GCC. In
this case a GCC bug meant that a DIE was linked via DW_AT_abstract_origin
to the wrong DIE. Instead of pointing at the abstract DIE, GCC was
linking one instance DIE to an earlier instance DIE. The first instance
DIE had low/high pc attributes, while the second instance DIE had a
ranges attribute. When processing the incorrectly linked instance GDB
would see a DIE with both a low/high pc and some ranges data. However,
the ranges data was all outside the low/high range, which would trigger
asserts when setting the entry-pc. */
attr_high = dwarf2_attr (die, DW_AT_high_pc, cu);
if (attr_high)
{
attr = dwarf2_attr (die, DW_AT_low_pc, cu);
if (attr != nullptr)
{
unrelocated_addr unrel_low = attr->as_address ();
unrelocated_addr unrel_high = attr_high->as_address ();
if (cu->header.version >= 4 && attr_high->form_is_constant ())
unrel_high = (unrelocated_addr) ((ULONGEST) unrel_high
+ (ULONGEST) unrel_low);
CORE_ADDR low = per_objfile->relocate (unrel_low);
CORE_ADDR high = per_objfile->relocate (unrel_high);
fixup_low_high_pc (cu, die, &low, &high);
cu->get_builder ()->record_block_range (block, low, high - 1);
}
attr = dwarf2_attr (die, DW_AT_ranges, cu);
if (attr != nullptr && attr->form_is_unsigned ())
complaint (_("in %s, DIE %s, DW_AT_ranges ignored due to DW_AT_low_pc"),
objfile_name (per_objfile->objfile),
sect_offset_str (die->sect_off));
}
else
{
attr = dwarf2_attr (die, DW_AT_ranges, cu);
if (attr != nullptr && attr->form_is_unsigned ())
{
/* Offset in the .debug_ranges or .debug_rnglist section (depending
on DWARF version). */
ULONGEST ranges_offset = attr->as_unsigned ();
/* See dwarf2_cu::gnu_ranges_base's doc for why we might want to add
this value. */
if (die->tag != DW_TAG_compile_unit)
ranges_offset += cu->gnu_ranges_base;
std::vector<blockrange> blockvec;
dwarf2_ranges_process (ranges_offset, cu, die->tag,
[&] (unrelocated_addr start,
unrelocated_addr end)
{
CORE_ADDR abs_start = per_objfile->relocate (start);
CORE_ADDR abs_end = per_objfile->relocate (end);
cu->get_builder ()->record_block_range (block, abs_start,
abs_end - 1);
blockvec.emplace_back (abs_start, abs_end);
});
block->set_ranges (make_blockranges (objfile, blockvec));
}
}
dwarf2_record_block_entry_pc (die, block, cu);
}
/* Return the accessibility of DIE, as given by DW_AT_accessibility.
If that attribute is not available, return the appropriate
default. */
static enum dwarf_access_attribute
dwarf2_access_attribute (struct die_info *die, struct dwarf2_cu *cu)
{
attribute *attr = dwarf2_attr (die, DW_AT_accessibility, cu);
if (attr != nullptr)
{
std::optional<ULONGEST> value = attr->unsigned_constant ();
if (value.has_value ())
{
if (*value == DW_ACCESS_public
|| *value == DW_ACCESS_protected
|| *value == DW_ACCESS_private)
return (dwarf_access_attribute) *value;
complaint (_("Unhandled DW_AT_accessibility value (%s)"),
pulongest (*value));
}
}
if (cu->header.version < 3 || cu->producer_is_gxx_lt_4_6 ())
{
/* The default DWARF 2 accessibility for members is public, the default
accessibility for inheritance is private. */
if (die->tag != DW_TAG_inheritance)
return DW_ACCESS_public;
else
return DW_ACCESS_private;
}
else
{
/* DWARF 3+ defines the default accessibility a different way. The same
rules apply now for DW_TAG_inheritance as for the members and it only
depends on the container kind. */
if (die->parent->tag == DW_TAG_class_type)
return DW_ACCESS_private;
else
return DW_ACCESS_public;
}
}
/* Look for DW_AT_data_member_location or DW_AT_data_bit_offset. Set
*OFFSET to the byte offset. If the attribute was not found return
0, otherwise return 1. If it was found but could not properly be
handled, set *OFFSET to 0. */
static int
handle_member_location (struct die_info *die, struct dwarf2_cu *cu,
LONGEST *offset)
{
struct attribute *attr;
attr = dwarf2_attr (die, DW_AT_data_member_location, cu);
if (attr != NULL)
{
*offset = 0;
CORE_ADDR temp;
/* Note that we do not check for a section offset first here.
This is because DW_AT_data_member_location is new in DWARF 4,
so if we see it, we can assume that a constant form is really
a constant and not a section offset. */
if (attr->form_is_constant ())
*offset = attr->constant_value (0);
else if (attr->form_is_section_offset ())
dwarf2_complex_location_expr_complaint ();
else if (attr->form_is_block ()
&& decode_locdesc (attr->as_block (), cu, &temp))
{
*offset = temp;
}
else
dwarf2_complex_location_expr_complaint ();
return 1;
}
else
{
attr = dwarf2_attr (die, DW_AT_data_bit_offset, cu);
if (attr != nullptr)
{
*offset = attr->constant_value (0);
return 1;
}
}
return 0;
}
/* Look for DW_AT_data_member_location or DW_AT_data_bit_offset and
store the results in FIELD. */
static void
handle_member_location (struct die_info *die, struct dwarf2_cu *cu,
struct field *field)
{
struct attribute *attr;
attr = dwarf2_attr (die, DW_AT_data_member_location, cu);
if (attr != NULL)
{
if (attr->form_is_constant ())
{
LONGEST offset = attr->constant_value (0);
/* Work around this GCC 11 bug, where it would erroneously use -1
data member locations, instead of 0:
Negative DW_AT_data_member_location
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101378
*/
if (offset == -1 && cu->producer_is_gcc_11 ())
{
complaint (_("DW_AT_data_member_location value of -1, assuming 0"));
offset = 0;
}
field->set_loc_bitpos (offset * bits_per_byte);
}
else if (attr->form_is_section_offset ())
dwarf2_complex_location_expr_complaint ();
else if (attr->form_is_block ())
{
CORE_ADDR offset;
if (decode_locdesc (attr->as_block (), cu, &offset))
field->set_loc_bitpos (offset * bits_per_byte);
else
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct dwarf2_locexpr_baton *dlbaton
= XOBNEW (&objfile->objfile_obstack,
struct dwarf2_locexpr_baton);
dlbaton->data = attr->as_block ()->data;
dlbaton->size = attr->as_block ()->size;
/* When using this baton, we want to compute the address
of the field, not the value. This is why
is_reference is set to false here. */
dlbaton->is_reference = false;
dlbaton->per_objfile = per_objfile;
dlbaton->per_cu = cu->per_cu;
field->set_loc_dwarf_block (dlbaton);
}
}
else
dwarf2_complex_location_expr_complaint ();
}
else
{
attr = dwarf2_attr (die, DW_AT_data_bit_offset, cu);
if (attr != nullptr)
field->set_loc_bitpos (attr->constant_value (0));
}
}
/* Add an aggregate field to the field list. */
static void
dwarf2_add_field (struct field_info *fip, struct die_info *die,
struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct gdbarch *gdbarch = objfile->arch ();
struct nextfield *new_field;
struct attribute *attr;
struct field *fp;
const char *fieldname = "";
if (die->tag == DW_TAG_inheritance)
new_field = &fip->baseclasses.emplace_back ();
else
new_field = &fip->fields.emplace_back ();
new_field->offset = die->sect_off;
switch (dwarf2_access_attribute (die, cu))
{
case DW_ACCESS_public:
break;
case DW_ACCESS_private:
new_field->field.set_accessibility (accessibility::PRIVATE);
break;
case DW_ACCESS_protected:
new_field->field.set_accessibility (accessibility::PROTECTED);
break;
default:
gdb_assert_not_reached ("invalid accessibility");
}
attr = dwarf2_attr (die, DW_AT_virtuality, cu);
if (attr != nullptr && attr->as_virtuality ())
new_field->field.set_virtual ();
fp = &new_field->field;
if ((die->tag == DW_TAG_member || die->tag == DW_TAG_namelist_item)
&& !die_is_declaration (die, cu))
{
if (die->tag == DW_TAG_namelist_item)
{
/* Typically, DW_TAG_namelist_item are references to namelist items.
If so, follow that reference. */
struct attribute *attr1 = dwarf2_attr (die, DW_AT_namelist_item, cu);
struct die_info *item_die = nullptr;
struct dwarf2_cu *item_cu = cu;
if (attr1->form_is_ref ())
item_die = follow_die_ref (die, attr1, &item_cu);
if (item_die != nullptr)
die = item_die;
}
/* Data member other than a C++ static data member. */
/* Get type of field. */
fp->set_type (die_type (die, cu));
fp->set_loc_bitpos (0);
/* Get bit size of field (zero if none). */
attr = dwarf2_attr (die, DW_AT_bit_size, cu);
if (attr != nullptr)
fp->set_bitsize (attr->constant_value (0));
else
fp->set_bitsize (0);
/* Get bit offset of field. */
handle_member_location (die, cu, fp);
attr = dwarf2_attr (die, DW_AT_bit_offset, cu);
if (attr != nullptr && attr->form_is_constant ())
{
if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
{
/* For big endian bits, the DW_AT_bit_offset gives the
additional bit offset from the MSB of the containing
anonymous object to the MSB of the field. We don't
have to do anything special since we don't need to
know the size of the anonymous object. */
fp->set_loc_bitpos (fp->loc_bitpos () + attr->constant_value (0));
}
else
{
/* For little endian bits, compute the bit offset to the
MSB of the anonymous object, subtract off the number of
bits from the MSB of the field to the MSB of the
object, and then subtract off the number of bits of
the field itself. The result is the bit offset of
the LSB of the field. */
int anonymous_size;
int bit_offset = attr->constant_value (0);
attr = dwarf2_attr (die, DW_AT_byte_size, cu);
if (attr != nullptr && attr->form_is_constant ())
{
/* The size of the anonymous object containing
the bit field is explicit, so use the
indicated size (in bytes). */
anonymous_size = attr->constant_value (0);
}
else
{
/* The size of the anonymous object containing
the bit field must be inferred from the type
attribute of the data member containing the
bit field. */
anonymous_size = fp->type ()->length ();
}
fp->set_loc_bitpos (fp->loc_bitpos ()
+ anonymous_size * bits_per_byte
- bit_offset - fp->bitsize ());
}
}
/* Get name of field. */
fieldname = dwarf2_name (die, cu);
if (fieldname == NULL)
fieldname = "";
/* The name is already allocated along with this objfile, so we don't
need to duplicate it for the type. */
fp->set_name (fieldname);
/* Change accessibility for artificial fields (e.g. virtual table
pointer or virtual base class pointer) to private. */
if (dwarf2_attr (die, DW_AT_artificial, cu))
{
fp->set_is_artificial (true);
fp->set_accessibility (accessibility::PRIVATE);
}
}
else if (die->tag == DW_TAG_member || die->tag == DW_TAG_variable)
{
/* C++ static member. */
/* NOTE: carlton/2002-11-05: It should be a DW_TAG_member that
is a declaration, but all versions of G++ as of this writing
(so through at least 3.2.1) incorrectly generate
DW_TAG_variable tags. */
const char *physname;
/* Get name of field. */
fieldname = dwarf2_name (die, cu);
if (fieldname == NULL)
return;
attr = dwarf2_attr (die, DW_AT_const_value, cu);
if (attr
/* Only create a symbol if this is an external value.
new_symbol checks this and puts the value in the global symbol
table, which we want. If it is not external, new_symbol
will try to put the value in cu->list_in_scope which is wrong. */
&& dwarf2_flag_true_p (die, DW_AT_external, cu))
{
/* A static const member, not much different than an enum as far as
we're concerned, except that we can support more types. */
new_symbol (die, NULL, cu);
}
/* Get physical name. */
physname = dwarf2_physname (fieldname, die, cu);
/* The name is already allocated along with this objfile, so we don't
need to duplicate it for the type. */
fp->set_loc_physname (physname ? physname : "");
fp->set_type (die_type (die, cu));
fp->set_name (fieldname);
}
else if (die->tag == DW_TAG_inheritance)
{
/* C++ base class field. */
handle_member_location (die, cu, fp);
fp->set_bitsize (0);
fp->set_type (die_type (die, cu));
fp->set_name (fp->type ()->name ());
}
else
gdb_assert_not_reached ("missing case in dwarf2_add_field");
}
/* Can the type given by DIE define another type? */
static bool
type_can_define_types (const struct die_info *die)
{
switch (die->tag)
{
case DW_TAG_typedef:
case DW_TAG_class_type:
case DW_TAG_structure_type:
case DW_TAG_union_type:
case DW_TAG_enumeration_type:
return true;
default:
return false;
}
}
/* Add a type definition defined in the scope of the FIP's class. */
static void
dwarf2_add_type_defn (struct field_info *fip, struct die_info *die,
struct dwarf2_cu *cu)
{
struct decl_field fp;
memset (&fp, 0, sizeof (fp));
gdb_assert (type_can_define_types (die));
/* Get name of field. NULL is okay here, meaning an anonymous type. */
fp.name = dwarf2_name (die, cu);
fp.type = read_type_die (die, cu);
/* Save accessibility. */
dwarf_access_attribute accessibility = dwarf2_access_attribute (die, cu);
switch (accessibility)
{
case DW_ACCESS_public:
/* The assumed value if neither private nor protected. */
break;
case DW_ACCESS_private:
fp.accessibility = accessibility::PRIVATE;
break;
case DW_ACCESS_protected:
fp.accessibility = accessibility::PROTECTED;
break;
}
if (die->tag == DW_TAG_typedef)
fip->typedef_field_list.push_back (fp);
else
fip->nested_types_list.push_back (fp);
}
/* A convenience typedef that's used when finding the discriminant
field for a variant part. */
using offset_map_type = gdb::unordered_map<sect_offset, int>;
/* Compute the discriminant range for a given variant. OBSTACK is
where the results will be stored. VARIANT is the variant to
process. IS_UNSIGNED indicates whether the discriminant is signed
or unsigned. */
static const gdb::array_view<discriminant_range>
convert_variant_range (struct obstack *obstack, const variant_field &variant,
bool is_unsigned)
{
std::vector<discriminant_range> ranges;
if (variant.default_branch)
return {};
if (variant.discr_list_data == nullptr)
{
discriminant_range r
= {variant.discriminant_value, variant.discriminant_value};
ranges.push_back (r);
}
else
{
gdb::array_view<const gdb_byte> data (variant.discr_list_data->data,
variant.discr_list_data->size);
while (!data.empty ())
{
if (data[0] != DW_DSC_range && data[0] != DW_DSC_label)
{
complaint (_("invalid discriminant marker: %d"), data[0]);
break;
}
bool is_range = data[0] == DW_DSC_range;
data = data.slice (1);
ULONGEST low, high;
unsigned int bytes_read;
if (data.empty ())
{
complaint (_("DW_AT_discr_list missing low value"));
break;
}
if (is_unsigned)
low = read_unsigned_leb128 (nullptr, data.data (), &bytes_read);
else
low = (ULONGEST) read_signed_leb128 (nullptr, data.data (),
&bytes_read);
data = data.slice (bytes_read);
if (is_range)
{
if (data.empty ())
{
complaint (_("DW_AT_discr_list missing high value"));
break;
}
if (is_unsigned)
high = read_unsigned_leb128 (nullptr, data.data (),
&bytes_read);
else
high = (LONGEST) read_signed_leb128 (nullptr, data.data (),
&bytes_read);
data = data.slice (bytes_read);
}
else
high = low;
ranges.push_back ({ low, high });
}
}
discriminant_range *result = XOBNEWVEC (obstack, discriminant_range,
ranges.size ());
std::copy (ranges.begin (), ranges.end (), result);
return gdb::array_view<discriminant_range> (result, ranges.size ());
}
static const gdb::array_view<variant_part> create_variant_parts
(struct obstack *obstack,
const offset_map_type &offset_map,
struct field_info *fi,
const std::vector<variant_part_builder> &variant_parts);
/* Fill in a "struct variant" for a given variant field. RESULT is
the variant to fill in. OBSTACK is where any needed allocations
will be done. OFFSET_MAP holds the mapping from section offsets to
fields for the type. FI describes the fields of the type we're
processing. FIELD is the variant field we're converting. */
static void
create_one_variant (variant &result, struct obstack *obstack,
const offset_map_type &offset_map,
struct field_info *fi, const variant_field &field)
{
result.discriminants = convert_variant_range (obstack, field, false);
result.first_field = field.first_field + fi->baseclasses.size ();
result.last_field = field.last_field + fi->baseclasses.size ();
result.parts = create_variant_parts (obstack, offset_map, fi,
field.variant_parts);
}
/* Fill in a "struct variant_part" for a given variant part. RESULT
is the variant part to fill in. OBSTACK is where any needed
allocations will be done. OFFSET_MAP holds the mapping from
section offsets to fields for the type. FI describes the fields of
the type we're processing. BUILDER is the variant part to be
converted. */
static void
create_one_variant_part (variant_part &result,
struct obstack *obstack,
const offset_map_type &offset_map,
struct field_info *fi,
const variant_part_builder &builder)
{
auto iter = offset_map.find (builder.discriminant_offset);
if (iter == offset_map.end ())
{
result.discriminant_index = -1;
/* Doesn't matter. */
result.is_unsigned = false;
}
else
{
result.discriminant_index = iter->second;
result.is_unsigned
= fi->fields[result.discriminant_index].field.type ()->is_unsigned ();
}
size_t n = builder.variants.size ();
variant *output = new (obstack) variant[n];
for (size_t i = 0; i < n; ++i)
create_one_variant (output[i], obstack, offset_map, fi,
builder.variants[i]);
result.variants = gdb::array_view<variant> (output, n);
}
/* Create a vector of variant parts that can be attached to a type.
OBSTACK is where any needed allocations will be done. OFFSET_MAP
holds the mapping from section offsets to fields for the type. FI
describes the fields of the type we're processing. VARIANT_PARTS
is the vector to convert. */
static const gdb::array_view<variant_part>
create_variant_parts (struct obstack *obstack,
const offset_map_type &offset_map,
struct field_info *fi,
const std::vector<variant_part_builder> &variant_parts)
{
if (variant_parts.empty ())
return {};
size_t n = variant_parts.size ();
variant_part *result = new (obstack) variant_part[n];
for (size_t i = 0; i < n; ++i)
create_one_variant_part (result[i], obstack, offset_map, fi,
variant_parts[i]);
return gdb::array_view<variant_part> (result, n);
}
/* Compute the variant part vector for FIP, attaching it to TYPE when
done. */
static void
add_variant_property (struct field_info *fip, struct type *type,
struct dwarf2_cu *cu)
{
/* Map section offsets of fields to their field index. Note the
field index here does not take the number of baseclasses into
account. */
offset_map_type offset_map;
for (int i = 0; i < fip->fields.size (); ++i)
offset_map[fip->fields[i].offset] = i;
struct objfile *objfile = cu->per_objfile->objfile;
gdb::array_view<const variant_part> parts
= create_variant_parts (&objfile->objfile_obstack, offset_map, fip,
fip->variant_parts);
struct dynamic_prop prop;
prop.set_variant_parts ((gdb::array_view<variant_part> *)
obstack_copy (&objfile->objfile_obstack, &parts,
sizeof (parts)));
type->add_dyn_prop (DYN_PROP_VARIANT_PARTS, prop);
}
/* Create the vector of fields, and attach it to the type. */
static void
dwarf2_attach_fields_to_type (struct field_info *fip, struct type *type,
struct dwarf2_cu *cu)
{
int nfields = fip->nfields ();
/* Record the field count, allocate space for the array of fields,
and create blank accessibility bitfields if necessary. */
type->alloc_fields (nfields);
if (!fip->baseclasses.empty () && cu->lang () != language_ada)
{
ALLOCATE_CPLUS_STRUCT_TYPE (type);
TYPE_N_BASECLASSES (type) = fip->baseclasses.size ();
}
if (!fip->variant_parts.empty ())
add_variant_property (fip, type, cu);
/* Copy the saved-up fields into the field vector. */
for (int i = 0; i < nfields; ++i)
{
struct nextfield &field
= ((i < fip->baseclasses.size ()) ? fip->baseclasses[i]
: fip->fields[i - fip->baseclasses.size ()]);
type->field (i) = field.field;
}
}
/* Return true if this member function is a constructor, false
otherwise. */
static int
dwarf2_is_constructor (struct die_info *die, struct dwarf2_cu *cu)
{
const char *fieldname;
const char *type_name;
int len;
if (die->parent == NULL)
return 0;
if (die->parent->tag != DW_TAG_structure_type
&& die->parent->tag != DW_TAG_union_type
&& die->parent->tag != DW_TAG_class_type)
return 0;
fieldname = dwarf2_name (die, cu);
type_name = dwarf2_name (die->parent, cu);
if (fieldname == NULL || type_name == NULL)
return 0;
len = strlen (fieldname);
return (strncmp (fieldname, type_name, len) == 0
&& (type_name[len] == '\0' || type_name[len] == '<'));
}
/* Add a member function to the proper fieldlist. */
static void
dwarf2_add_member_fn (struct field_info *fip, struct die_info *die,
struct type *type, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct attribute *attr;
int i;
struct fnfieldlist *flp = nullptr;
struct fn_field *fnp;
const char *fieldname;
struct type *this_type;
if (cu->lang () == language_ada)
error (_("unexpected member function in Ada type"));
/* Get name of member function. */
fieldname = dwarf2_name (die, cu);
if (fieldname == NULL)
return;
/* Look up member function name in fieldlist. */
for (i = 0; i < fip->fnfieldlists.size (); i++)
{
if (strcmp (fip->fnfieldlists[i].name, fieldname) == 0)
{
flp = &fip->fnfieldlists[i];
break;
}
}
/* Create a new fnfieldlist if necessary. */
if (flp == nullptr)
{
flp = &fip->fnfieldlists.emplace_back ();
flp->name = fieldname;
i = fip->fnfieldlists.size () - 1;
}
/* Create a new member function field and add it to the vector of
fnfieldlists. */
fnp = &flp->fnfields.emplace_back ();
/* Delay processing of the physname until later. */
if (cu->lang () == language_cplus)
add_to_method_list (type, i, flp->fnfields.size () - 1, fieldname,
die, cu);
else
{
const char *physname = dwarf2_physname (fieldname, die, cu);
fnp->physname = physname ? physname : "";
}
fnp->type = type_allocator (objfile, cu->lang ()).new_type ();
this_type = read_type_die (die, cu);
if (this_type && this_type->code () == TYPE_CODE_FUNC)
{
int nparams = this_type->num_fields ();
/* TYPE is the domain of this method, and THIS_TYPE is the type
of the method itself (TYPE_CODE_METHOD). */
smash_to_method_type (fnp->type, type,
this_type->target_type (),
this_type->fields (),
this_type->num_fields (),
this_type->has_varargs ());
/* Handle static member functions.
Dwarf2 has no clean way to discern C++ static and non-static
member functions. G++ helps GDB by marking the first
parameter for non-static member functions (which is the this
pointer) as artificial. We obtain this information from
read_subroutine_type via TYPE_FIELD_ARTIFICIAL. */
if (nparams == 0 || this_type->field (0).is_artificial () == 0)
fnp->voffset = VOFFSET_STATIC;
}
else
complaint (_("member function type missing for '%s'"),
dwarf2_full_name (fieldname, die, cu));
/* Get fcontext from DW_AT_containing_type if present. */
if (dwarf2_attr (die, DW_AT_containing_type, cu) != NULL)
fnp->fcontext = die_containing_type (die, cu);
/* dwarf2 doesn't have stubbed physical names, so the setting of is_const and
is_volatile is irrelevant, as it is needed by gdb_mangle_name only. */
/* Get accessibility. */
dwarf_access_attribute accessibility = dwarf2_access_attribute (die, cu);
switch (accessibility)
{
case DW_ACCESS_private:
fnp->accessibility = accessibility::PRIVATE;
break;
case DW_ACCESS_protected:
fnp->accessibility = accessibility::PROTECTED;
break;
}
/* Check for artificial methods. */
attr = dwarf2_attr (die, DW_AT_artificial, cu);
if (attr && attr->as_boolean ())
fnp->is_artificial = 1;
/* Check for defaulted methods. */
attr = dwarf2_attr (die, DW_AT_defaulted, cu);
if (attr != nullptr)
fnp->defaulted = attr->defaulted ();
/* Check for deleted methods. */
attr = dwarf2_attr (die, DW_AT_deleted, cu);
if (attr != nullptr && attr->as_boolean ())
fnp->is_deleted = 1;
fnp->is_constructor = dwarf2_is_constructor (die, cu);
/* Get index in virtual function table if it is a virtual member
function. For older versions of GCC, this is an offset in the
appropriate virtual table, as specified by DW_AT_containing_type.
For everyone else, it is an expression to be evaluated relative
to the object address. */
attr = dwarf2_attr (die, DW_AT_vtable_elem_location, cu);
if (attr != nullptr)
{
if (attr->form_is_block () && attr->as_block ()->size > 0)
{
struct dwarf_block *block = attr->as_block ();
CORE_ADDR offset;
if (block->data[0] == DW_OP_constu
&& decode_locdesc (block, cu, &offset))
{
/* "Old"-style GCC. See
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=44126
for discussion. This was known and a patch available
in 2010, but as of 2023, both GCC and clang still
emit this. */
fnp->voffset = offset + 2;
}
else if ((block->data[0] == DW_OP_deref
|| (block->size > 1
&& block->data[0] == DW_OP_deref_size
&& block->data[1] == cu->header.addr_size))
&& decode_locdesc (block, cu, &offset))
{
fnp->voffset = offset;
if ((fnp->voffset % cu->header.addr_size) != 0)
dwarf2_complex_location_expr_complaint ();
else
fnp->voffset /= cu->header.addr_size;
fnp->voffset += 2;
}
else
dwarf2_complex_location_expr_complaint ();
if (!fnp->fcontext)
{
/* If there is no `this' field and no DW_AT_containing_type,
we cannot actually find a base class context for the
vtable! */
if (this_type->num_fields () == 0
|| !this_type->field (0).is_artificial ())
{
complaint (_("cannot determine context for virtual member "
"function \"%s\" (offset %s)"),
fieldname, sect_offset_str (die->sect_off));
}
else
{
fnp->fcontext = this_type->field (0).type ()->target_type ();
}
}
}
else if (attr->form_is_section_offset ())
{
dwarf2_complex_location_expr_complaint ();
}
else
{
dwarf2_invalid_attrib_class_complaint ("DW_AT_vtable_elem_location",
fieldname);
}
}
else
{
attr = dwarf2_attr (die, DW_AT_virtuality, cu);
if (attr != nullptr && attr->as_virtuality () != DW_VIRTUALITY_none)
{
/* GCC does this, as of 2008-08-25; PR debug/37237. */
complaint (_("Member function \"%s\" (offset %s) is virtual "
"but the vtable offset is not specified"),
fieldname, sect_offset_str (die->sect_off));
ALLOCATE_CPLUS_STRUCT_TYPE (type);
TYPE_CPLUS_DYNAMIC (type) = 1;
}
}
}
/* Create the vector of member function fields, and attach it to the type. */
static void
dwarf2_attach_fn_fields_to_type (struct field_info *fip, struct type *type,
struct dwarf2_cu *cu)
{
if (cu->lang () == language_ada)
error (_("unexpected member functions in Ada type"));
ALLOCATE_CPLUS_STRUCT_TYPE (type);
TYPE_FN_FIELDLISTS (type) = (struct fn_fieldlist *)
TYPE_ZALLOC (type,
sizeof (struct fn_fieldlist) * fip->fnfieldlists.size ());
for (int i = 0; i < fip->fnfieldlists.size (); i++)
{
struct fnfieldlist &nf = fip->fnfieldlists[i];
struct fn_fieldlist *fn_flp = &TYPE_FN_FIELDLIST (type, i);
TYPE_FN_FIELDLIST_NAME (type, i) = nf.name;
TYPE_FN_FIELDLIST_LENGTH (type, i) = nf.fnfields.size ();
/* No need to zero-initialize, initialization is done by the copy in
the loop below. */
fn_flp->fn_fields = (struct fn_field *)
TYPE_ALLOC (type, sizeof (struct fn_field) * nf.fnfields.size ());
for (int k = 0; k < nf.fnfields.size (); ++k)
fn_flp->fn_fields[k] = nf.fnfields[k];
}
TYPE_NFN_FIELDS (type) = fip->fnfieldlists.size ();
}
/* Returns non-zero if NAME is the name of a vtable member in CU's
language, zero otherwise. */
static int
is_vtable_name (const char *name, struct dwarf2_cu *cu)
{
static const char vptr[] = "_vptr";
/* Look for the C++ form of the vtable. */
if (startswith (name, vptr) && is_cplus_marker (name[sizeof (vptr) - 1]))
return 1;
return 0;
}
/* GCC outputs unnamed structures that are really pointers to member
functions, with the ABI-specified layout. If TYPE describes
such a structure, smash it into a member function type.
GCC shouldn't do this; it should just output pointer to member DIEs.
This is GCC PR debug/28767. */
static void
quirk_gcc_member_function_pointer (struct type *type, struct objfile *objfile)
{
struct type *pfn_type, *self_type, *new_type;
/* Check for a structure with no name and two children. */
if (type->code () != TYPE_CODE_STRUCT || type->num_fields () != 2)
return;
/* Check for __pfn and __delta members. */
if (type->field (0).name () == NULL
|| strcmp (type->field (0).name (), "__pfn") != 0
|| type->field (1).name () == NULL
|| strcmp (type->field (1).name (), "__delta") != 0)
return;
/* Find the type of the method. */
pfn_type = type->field (0).type ();
if (pfn_type == NULL
|| pfn_type->code () != TYPE_CODE_PTR
|| pfn_type->target_type ()->code () != TYPE_CODE_FUNC)
return;
/* Look for the "this" argument. */
pfn_type = pfn_type->target_type ();
if (pfn_type->num_fields () == 0
/* || pfn_type->field (0).type () == NULL */
|| pfn_type->field (0).type ()->code () != TYPE_CODE_PTR)
return;
self_type = pfn_type->field (0).type ()->target_type ();
new_type = type_allocator (type).new_type ();
smash_to_method_type (new_type, self_type, pfn_type->target_type (),
pfn_type->fields (), pfn_type->num_fields (),
pfn_type->has_varargs ());
smash_to_methodptr_type (type, new_type);
}
/* Helper for quirk_ada_thick_pointer. If TYPE is an array type that
requires rewriting, then copy it and return the updated copy.
Otherwise return nullptr. */
static struct type *
rewrite_array_type (struct type *type)
{
if (type->code () != TYPE_CODE_ARRAY)
return nullptr;
struct type *index_type = type->index_type ();
range_bounds *current_bounds = index_type->bounds ();
/* Handle multi-dimensional arrays. */
struct type *new_target = rewrite_array_type (type->target_type ());
if (new_target == nullptr)
{
/* Maybe we don't need to rewrite this array. */
if (current_bounds->low.is_constant ()
&& current_bounds->high.is_constant ())
return nullptr;
}
/* Either the target type was rewritten, or the bounds have to be
updated. Either way we want to copy the type and update
everything. */
struct type *copy = copy_type (type);
copy->copy_fields (type);
if (new_target != nullptr)
copy->set_target_type (new_target);
struct type *index_copy = copy_type (index_type);
range_bounds *bounds
= (struct range_bounds *) TYPE_ZALLOC (index_copy,
sizeof (range_bounds));
*bounds = *current_bounds;
bounds->low.set_const_val (1);
bounds->high.set_const_val (0);
index_copy->set_bounds (bounds);
copy->set_index_type (index_copy);
return copy;
}
/* While some versions of GCC will generate complicated DWARF for an
array (see quirk_ada_thick_pointer), more recent versions were
modified to emit an explicit thick pointer structure. However, in
this case, the array still has DWARF expressions for its ranges,
and these must be ignored. */
static void
quirk_ada_thick_pointer_struct (struct die_info *die, struct dwarf2_cu *cu,
struct type *type)
{
gdb_assert (cu->lang () == language_ada);
/* Check for a structure with two children. */
if (type->code () != TYPE_CODE_STRUCT || type->num_fields () != 2)
return;
/* Check for P_ARRAY and P_BOUNDS members. */
if (type->field (0).name () == NULL
|| strcmp (type->field (0).name (), "P_ARRAY") != 0
|| type->field (1).name () == NULL
|| strcmp (type->field (1).name (), "P_BOUNDS") != 0)
return;
/* Make sure we're looking at a pointer to an array. */
if (type->field (0).type ()->code () != TYPE_CODE_PTR)
return;
/* The Ada code already knows how to handle these types, so all that
we need to do is turn the bounds into static bounds. However, we
don't want to rewrite existing array or index types in-place,
because those may be referenced in other contexts where this
rewriting is undesirable. */
struct type *new_ary_type
= rewrite_array_type (type->field (0).type ()->target_type ());
if (new_ary_type != nullptr)
type->field (0).set_type (lookup_pointer_type (new_ary_type));
}
/* If the DIE has a DW_AT_alignment attribute, return its value, doing
appropriate error checking and issuing complaints if there is a
problem. */
static ULONGEST
get_alignment (struct dwarf2_cu *cu, struct die_info *die)
{
struct attribute *attr = dwarf2_attr (die, DW_AT_alignment, cu);
if (attr == nullptr)
return 0;
if (!attr->form_is_constant ())
{
complaint (_("DW_AT_alignment must have constant form"
" - DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
return 0;
}
std::optional<ULONGEST> val = attr->unsigned_constant ();
if (!val.has_value ())
return 0;
ULONGEST align = *val;
if (align == 0)
{
complaint (_("DW_AT_alignment value must not be zero"
" - DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
return 0;
}
if ((align & (align - 1)) != 0)
{
complaint (_("DW_AT_alignment value must be a power of 2"
" - DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
return 0;
}
return align;
}
/* If the DIE has a DW_AT_alignment attribute, use its value to set
the alignment for TYPE. */
static void
maybe_set_alignment (struct dwarf2_cu *cu, struct die_info *die,
struct type *type)
{
if (!set_type_align (type, get_alignment (cu, die)))
complaint (_("DW_AT_alignment value too large"
" - DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
}
/* Check if the given VALUE is a valid enum dwarf_calling_convention
constant for a type, according to DWARF5 spec, Table 5.5. */
static bool
is_valid_DW_AT_calling_convention_for_type (ULONGEST value)
{
switch (value)
{
case DW_CC_normal:
case DW_CC_pass_by_reference:
case DW_CC_pass_by_value:
return true;
default:
complaint (_("unrecognized DW_AT_calling_convention value "
"(%s) for a type"), pulongest (value));
return false;
}
}
/* Check if the given VALUE is a valid enum dwarf_calling_convention
constant for a subroutine, according to DWARF5 spec, Table 3.3, and
also according to GNU-specific values (see include/dwarf2.h). */
static bool
is_valid_DW_AT_calling_convention_for_subroutine (ULONGEST value)
{
switch (value)
{
case DW_CC_normal:
case DW_CC_program:
case DW_CC_nocall:
return true;
case DW_CC_GNU_renesas_sh:
case DW_CC_GNU_borland_fastcall_i386:
case DW_CC_GDB_IBM_OpenCL:
return true;
default:
complaint (_("unrecognized DW_AT_calling_convention value "
"(%s) for a subroutine"), pulongest (value));
return false;
}
}
/* Called when we find the DIE that starts a structure or union scope
(definition) to create a type for the structure or union. Fill in
the type's name and general properties; the members will not be
processed until process_structure_scope. A symbol table entry for
the type will also not be done until process_structure_scope (assuming
the type has a name).
NOTE: we need to call these functions regardless of whether or not the
DIE has a DW_AT_name attribute, since it might be an anonymous
structure or union. This gets the type entered into our set of
user defined types. */
static struct type *
read_structure_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct type *type;
struct attribute *attr;
const char *name;
/* If the definition of this type lives in .debug_types, read that type.
Don't follow DW_AT_specification though, that will take us back up
the chain and we want to go down. */
attr = die->attr (DW_AT_signature);
if (attr != nullptr)
{
type = get_DW_AT_signature_type (die, attr, cu);
/* The type's CU may not be the same as CU.
Ensure TYPE is recorded with CU in die_type_hash. */
return set_die_type (die, type, cu);
}
type = type_allocator (objfile, cu->lang ()).new_type ();
INIT_CPLUS_SPECIFIC (type);
name = dwarf2_name (die, cu);
if (name != NULL)
{
if (cu->lang () == language_cplus
|| cu->lang () == language_d
|| cu->lang () == language_rust
|| cu->lang () == language_ada)
{
const char *full_name = dwarf2_full_name (name, die, cu);
/* dwarf2_full_name might have already finished building the DIE's
type. If so, there is no need to continue. */
if (get_die_type (die, cu) != NULL)
return get_die_type (die, cu);
type->set_name (full_name);
}
else
{
/* The name is already allocated along with this objfile, so
we don't need to duplicate it for the type. */
type->set_name (name);
}
}
if (die->tag == DW_TAG_structure_type)
{
type->set_code (TYPE_CODE_STRUCT);
}
else if (die->tag == DW_TAG_union_type)
{
type->set_code (TYPE_CODE_UNION);
}
else if (die->tag == DW_TAG_namelist)
{
type->set_code (TYPE_CODE_NAMELIST);
}
else
{
type->set_code (TYPE_CODE_STRUCT);
}
if (cu->lang () == language_cplus && die->tag == DW_TAG_class_type)
type->set_is_declared_class (true);
/* Store the calling convention in the type if it's available in
the die. Otherwise the calling convention remains set to
the default value DW_CC_normal. */
attr = dwarf2_attr (die, DW_AT_calling_convention, cu);
if (attr != nullptr)
{
std::optional<ULONGEST> value = attr->unsigned_constant ();
if (value.has_value ()
&& is_valid_DW_AT_calling_convention_for_type (*value))
{
ALLOCATE_CPLUS_STRUCT_TYPE (type);
TYPE_CPLUS_CALLING_CONVENTION (type)
= (enum dwarf_calling_convention) *value;
}
}
attr = dwarf2_attr (die, DW_AT_byte_size, cu);
if (attr != nullptr)
{
if (attr->form_is_constant ())
type->set_length (attr->constant_value (0));
else
{
struct dynamic_prop prop;
if (attr_to_dynamic_prop (attr, die, cu, &prop, cu->addr_type ()))
type->add_dyn_prop (DYN_PROP_BYTE_SIZE, prop);
type->set_length (0);
}
}
else
type->set_length (0);
maybe_set_alignment (cu, die, type);
if (cu->producer_is_icc_lt_14 () && type->length () == 0)
{
/* ICC<14 does not output the required DW_AT_declaration on
incomplete types, but gives them a size of zero. */
type->set_is_stub (true);
}
else
type->set_stub_is_supported (true);
if (die_is_declaration (die, cu))
type->set_is_stub (true);
else if (attr == NULL && die->child == NULL
&& cu->producer_is_realview ())
/* RealView does not output the required DW_AT_declaration
on incomplete types. */
type->set_is_stub (true);
/* We need to add the type field to the die immediately so we don't
infinitely recurse when dealing with pointers to the structure
type within the structure itself. */
set_die_type (die, type, cu);
/* set_die_type should be already done. */
set_descriptive_type (type, die, cu);
return type;
}
static void handle_struct_member_die
(struct die_info *child_die,
struct type *type,
struct field_info *fi,
std::vector<struct symbol *> *template_args,
struct dwarf2_cu *cu);
/* A helper for handle_struct_member_die that handles
DW_TAG_variant_part. */
static void
handle_variant_part (struct die_info *die, struct type *type,
struct field_info *fi,
std::vector<struct symbol *> *template_args,
struct dwarf2_cu *cu)
{
variant_part_builder *new_part;
if (fi->current_variant_part == nullptr)
new_part = &fi->variant_parts.emplace_back ();
else if (!fi->current_variant_part->processing_variant)
{
complaint (_("nested DW_TAG_variant_part seen "
"- DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
return;
}
else
{
variant_field &current = fi->current_variant_part->variants.back ();
new_part = &current.variant_parts.emplace_back ();
}
/* When we recurse, we want callees to add to this new variant
part. */
scoped_restore save_current_variant_part
= make_scoped_restore (&fi->current_variant_part, new_part);
struct attribute *discr = dwarf2_attr (die, DW_AT_discr, cu);
if (discr == NULL)
{
/* It's a univariant form, an extension we support. */
}
else if (discr->form_is_ref ())
{
struct dwarf2_cu *target_cu = cu;
struct die_info *target_die = follow_die_ref (die, discr, &target_cu);
new_part->discriminant_offset = target_die->sect_off;
}
else
{
complaint (_("DW_AT_discr does not have DIE reference form"
" - DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
}
for (die_info *child_die = die->child;
child_die != NULL;
child_die = child_die->sibling)
handle_struct_member_die (child_die, type, fi, template_args, cu);
}
/* A helper for handle_struct_member_die that handles
DW_TAG_variant. */
static void
handle_variant (struct die_info *die, struct type *type,
struct field_info *fi,
std::vector<struct symbol *> *template_args,
struct dwarf2_cu *cu)
{
if (fi->current_variant_part == nullptr)
{
complaint (_("saw DW_TAG_variant outside DW_TAG_variant_part "
"- DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
return;
}
if (fi->current_variant_part->processing_variant)
{
complaint (_("nested DW_TAG_variant seen "
"- DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
return;
}
scoped_restore save_processing_variant
= make_scoped_restore (&fi->current_variant_part->processing_variant,
true);
variant_field &variant = fi->current_variant_part->variants.emplace_back ();
variant.first_field = fi->fields.size ();
/* In a variant we want to get the discriminant and also add a
field for our sole member child. */
struct attribute *discr = dwarf2_attr (die, DW_AT_discr_value, cu);
if (discr == nullptr || !discr->form_is_constant ())
{
discr = dwarf2_attr (die, DW_AT_discr_list, cu);
if (discr == nullptr || discr->as_block ()->size == 0)
variant.default_branch = true;
else
variant.discr_list_data = discr->as_block ();
}
else
variant.discriminant_value = discr->constant_value (0);
for (die_info *variant_child = die->child;
variant_child != NULL;
variant_child = variant_child->sibling)
handle_struct_member_die (variant_child, type, fi, template_args, cu);
variant.last_field = fi->fields.size ();
}
/* A helper for process_structure_scope that handles a single member
DIE. */
static void
handle_struct_member_die (struct die_info *child_die, struct type *type,
struct field_info *fi,
std::vector<struct symbol *> *template_args,
struct dwarf2_cu *cu)
{
if (child_die->tag == DW_TAG_member
|| child_die->tag == DW_TAG_variable
|| child_die->tag == DW_TAG_namelist_item)
{
/* NOTE: carlton/2002-11-05: A C++ static data member
should be a DW_TAG_member that is a declaration, but
all versions of G++ as of this writing (so through at
least 3.2.1) incorrectly generate DW_TAG_variable
tags for them instead. */
dwarf2_add_field (fi, child_die, cu);
}
else if (child_die->tag == DW_TAG_subprogram)
{
/* Rust doesn't have member functions in the C++ sense.
However, it does emit ordinary functions as children
of a struct DIE. */
if (cu->lang () == language_rust)
read_func_scope (child_die, cu);
else
{
/* C++ member function. */
dwarf2_add_member_fn (fi, child_die, type, cu);
}
}
else if (child_die->tag == DW_TAG_inheritance)
{
/* C++ base class field. */
dwarf2_add_field (fi, child_die, cu);
}
else if (type_can_define_types (child_die))
dwarf2_add_type_defn (fi, child_die, cu);
else if (child_die->tag == DW_TAG_template_type_param
|| child_die->tag == DW_TAG_template_value_param)
{
struct symbol *arg = new_symbol (child_die, NULL, cu);
if (arg != NULL)
template_args->push_back (arg);
}
else if (child_die->tag == DW_TAG_variant_part)
handle_variant_part (child_die, type, fi, template_args, cu);
else if (child_die->tag == DW_TAG_variant)
handle_variant (child_die, type, fi, template_args, cu);
}
/* Finish creating a structure or union type, including filling in its
members and creating a symbol for it. This function also handles Fortran
namelist variables, their items or members and creating a symbol for
them. */
static void
process_structure_scope (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct die_info *child_die;
struct type *type;
type = get_die_type (die, cu);
if (type == NULL)
type = read_structure_type (die, cu);
bool has_template_parameters = false;
if (die->child != NULL && ! die_is_declaration (die, cu))
{
struct field_info fi;
std::vector<struct symbol *> template_args;
child_die = die->child;
while (child_die && child_die->tag)
{
handle_struct_member_die (child_die, type, &fi, &template_args, cu);
child_die = child_die->sibling;
}
/* Attach template arguments to type. */
if (!template_args.empty ())
{
has_template_parameters = true;
ALLOCATE_CPLUS_STRUCT_TYPE (type);
TYPE_N_TEMPLATE_ARGUMENTS (type) = template_args.size ();
TYPE_TEMPLATE_ARGUMENTS (type)
= XOBNEWVEC (&objfile->objfile_obstack,
struct symbol *,
TYPE_N_TEMPLATE_ARGUMENTS (type));
memcpy (TYPE_TEMPLATE_ARGUMENTS (type),
template_args.data (),
(TYPE_N_TEMPLATE_ARGUMENTS (type)
* sizeof (struct symbol *)));
}
/* Attach fields and member functions to the type. */
if (fi.nfields () > 0)
dwarf2_attach_fields_to_type (&fi, type, cu);
if (!fi.fnfieldlists.empty ())
{
dwarf2_attach_fn_fields_to_type (&fi, type, cu);
/* Get the type which refers to the base class (possibly this
class itself) which contains the vtable pointer for the current
class from the DW_AT_containing_type attribute. This use of
DW_AT_containing_type is a GNU extension. */
if (dwarf2_attr (die, DW_AT_containing_type, cu) != NULL)
{
struct type *t = die_containing_type (die, cu);
set_type_vptr_basetype (type, t);
if (type == t)
{
int i;
/* Our own class provides vtbl ptr. */
for (i = t->num_fields () - 1;
i >= TYPE_N_BASECLASSES (t);
--i)
{
const char *fieldname = t->field (i).name ();
if (is_vtable_name (fieldname, cu))
{
set_type_vptr_fieldno (type, i);
break;
}
}
/* Complain if virtual function table field not found. */
if (i < TYPE_N_BASECLASSES (t))
complaint (_("virtual function table pointer "
"not found when defining class '%s'"),
type->name () ? type->name () : "");
}
else
{
set_type_vptr_fieldno (type, TYPE_VPTR_FIELDNO (t));
}
}
else if (cu->producer_is_xlc ())
{
/* The IBM XLC compiler does not provide direct indication
of the containing type, but the vtable pointer is
always named __vfp. */
int i;
for (i = type->num_fields () - 1;
i >= TYPE_N_BASECLASSES (type);
--i)
{
if (strcmp (type->field (i).name (), "__vfp") == 0)
{
set_type_vptr_fieldno (type, i);
set_type_vptr_basetype (type, type);
break;
}
}
}
}
/* Copy fi.typedef_field_list linked list elements content into the
allocated array TYPE_TYPEDEF_FIELD_ARRAY (type). */
if (!fi.typedef_field_list.empty ())
{
int count = fi.typedef_field_list.size ();
ALLOCATE_CPLUS_STRUCT_TYPE (type);
/* No zero-initialization is needed, the elements are initialized by
the copy in the loop below. */
TYPE_TYPEDEF_FIELD_ARRAY (type)
= ((struct decl_field *)
TYPE_ALLOC (type,
sizeof (TYPE_TYPEDEF_FIELD (type, 0)) * count));
TYPE_TYPEDEF_FIELD_COUNT (type) = count;
for (int i = 0; i < fi.typedef_field_list.size (); ++i)
TYPE_TYPEDEF_FIELD (type, i) = fi.typedef_field_list[i];
}
/* Copy fi.nested_types_list linked list elements content into the
allocated array TYPE_NESTED_TYPES_ARRAY (type). */
if (!fi.nested_types_list.empty ()
&& cu->lang () != language_ada)
{
int count = fi.nested_types_list.size ();
ALLOCATE_CPLUS_STRUCT_TYPE (type);
/* No zero-initialization is needed, the elements are initialized by
the copy in the loop below. */
TYPE_NESTED_TYPES_ARRAY (type)
= ((struct decl_field *)
TYPE_ALLOC (type, sizeof (struct decl_field) * count));
TYPE_NESTED_TYPES_COUNT (type) = count;
for (int i = 0; i < fi.nested_types_list.size (); ++i)
TYPE_NESTED_TYPES_FIELD (type, i) = fi.nested_types_list[i];
}
}
quirk_gcc_member_function_pointer (type, objfile);
if (cu->lang () == language_rust && die->tag == DW_TAG_union_type)
cu->rust_unions.push_back (type);
else if (cu->lang () == language_ada)
quirk_ada_thick_pointer_struct (die, cu, type);
/* NOTE: carlton/2004-03-16: GCC 3.4 (or at least one of its
snapshots) has been known to create a die giving a declaration
for a class that has, as a child, a die giving a definition for a
nested class. So we have to process our children even if the
current die is a declaration. Normally, of course, a declaration
won't have any children at all. */
child_die = die->child;
while (child_die != NULL && child_die->tag)
{
if (child_die->tag == DW_TAG_member
|| child_die->tag == DW_TAG_variable
|| child_die->tag == DW_TAG_inheritance
|| child_die->tag == DW_TAG_template_value_param
|| child_die->tag == DW_TAG_template_type_param)
{
/* Do nothing. */
}
else
process_die (child_die, cu);
child_die = child_die->sibling;
}
/* Do not consider external references. According to the DWARF standard,
these DIEs are identified by the fact that they have no byte_size
attribute, and a declaration attribute. */
if (dwarf2_attr (die, DW_AT_byte_size, cu) != NULL
|| !die_is_declaration (die, cu)
|| dwarf2_attr (die, DW_AT_signature, cu) != NULL)
{
struct symbol *sym = new_symbol (die, type, cu);
if (has_template_parameters)
{
struct symtab *symtab;
if (sym != nullptr)
symtab = sym->symtab ();
else if (cu->line_header != nullptr)
{
/* Any related symtab will do. */
symtab
= cu->line_header->file_names ()[0].symtab;
}
else
{
symtab = nullptr;
complaint (_("could not find suitable "
"symtab for template parameter"
" - DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (objfile));
}
if (symtab != nullptr)
{
/* Make sure that the symtab is set on the new symbols.
Even though they don't appear in this symtab directly,
other parts of gdb assume that symbols do, and this is
reasonably true. */
for (int i = 0; i < TYPE_N_TEMPLATE_ARGUMENTS (type); ++i)
TYPE_TEMPLATE_ARGUMENT (type, i)->set_symtab (symtab);
}
}
}
}
/* Read DW_AT_endianity from DIE and compute the byte order that
should be used. The CU's arch is used as the default. The result
is true if the returned arch differs from the default, and false if
they are the same. If provided, the out parameter BYTE_ORDER is
also set. */
static bool
die_byte_order (die_info *die, dwarf2_cu *cu, enum bfd_endian *byte_order)
{
gdbarch *arch = cu->per_objfile->objfile->arch ();
enum bfd_endian arch_order = gdbarch_byte_order (arch);
enum bfd_endian new_order = arch_order;
attribute *attr = dwarf2_attr (die, DW_AT_endianity, cu);
if (attr != nullptr && attr->form_is_constant ())
{
std::optional<ULONGEST> endianity = attr->unsigned_constant ();
if (endianity.has_value ())
{
switch (*endianity)
{
case DW_END_default:
/* Nothing. */
break;
case DW_END_big:
new_order = BFD_ENDIAN_BIG;
break;
case DW_END_little:
new_order = BFD_ENDIAN_LITTLE;
break;
default:
complaint (_("DW_AT_endianity has unrecognized value %s"),
pulongest (*endianity));
break;
}
}
}
if (byte_order != nullptr)
*byte_order = new_order;
return new_order != arch_order;
}
/* Assuming DIE is an enumeration type, and TYPE is its associated
type, update TYPE using some information only available in DIE's
children. In particular, the fields are computed. */
static void
update_enumeration_type_from_children (struct die_info *die,
struct type *type,
struct dwarf2_cu *cu)
{
struct die_info *child_die;
int unsigned_enum = 1;
int flag_enum = 1;
auto_obstack obstack;
std::vector<struct field> fields;
for (child_die = die->child;
child_die != NULL && child_die->tag;
child_die = child_die->sibling)
{
struct attribute *attr;
LONGEST value;
const gdb_byte *bytes;
struct dwarf2_locexpr_baton *baton;
const char *name;
if (child_die->tag != DW_TAG_enumerator)
continue;
attr = dwarf2_attr (child_die, DW_AT_const_value, cu);
if (attr == NULL)
continue;
name = dwarf2_name (child_die, cu);
if (name == NULL)
name = "<anonymous enumerator>";
dwarf2_const_value_attr (attr, type, name, &obstack, cu,
&value, &bytes, &baton);
if (value < 0)
{
unsigned_enum = 0;
flag_enum = 0;
}
else
{
if (count_one_bits_ll (value) >= 2)
flag_enum = 0;
}
struct field &field = fields.emplace_back ();
field.set_name (dwarf2_physname (name, child_die, cu));
field.set_loc_enumval (value);
}
if (!fields.empty ())
type->copy_fields (fields);
else
flag_enum = 0;
if (unsigned_enum)
type->set_is_unsigned (true);
if (flag_enum)
type->set_is_flag_enum (true);
}
/* Given a DW_AT_enumeration_type die, set its type. We do not
complete the type's fields yet, or create any symbols. */
static struct type *
read_enumeration_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct type *type;
struct attribute *attr;
const char *name;
/* If the definition of this type lives in .debug_types, read that type.
Don't follow DW_AT_specification though, that will take us back up
the chain and we want to go down. */
attr = die->attr (DW_AT_signature);
if (attr != nullptr)
{
type = get_DW_AT_signature_type (die, attr, cu);
/* The type's CU may not be the same as CU.
Ensure TYPE is recorded with CU in die_type_hash. */
return set_die_type (die, type, cu);
}
type = type_allocator (objfile, cu->lang ()).new_type ();
type->set_code (TYPE_CODE_ENUM);
name = dwarf2_full_name (NULL, die, cu);
if (name != NULL)
type->set_name (name);
attr = dwarf2_attr (die, DW_AT_type, cu);
if (attr != NULL)
{
struct type *underlying_type = die_type (die, cu);
type->set_target_type (underlying_type);
}
attr = dwarf2_attr (die, DW_AT_byte_size, cu);
if (attr != nullptr)
type->set_length (attr->constant_value (0));
else
type->set_length (0);
maybe_set_alignment (cu, die, type);
/* The enumeration DIE can be incomplete. In Ada, any type can be
declared as private in the package spec, and then defined only
inside the package body. Such types are known as Taft Amendment
Types. When another package uses such a type, an incomplete DIE
may be generated by the compiler. */
if (die_is_declaration (die, cu))
type->set_is_stub (true);
/* If this type has an underlying type that is not a stub, then we
may use its attributes. We always use the "unsigned" attribute
in this situation, because ordinarily we guess whether the type
is unsigned -- but the guess can be wrong and the underlying type
can tell us the reality. However, we defer to a local size
attribute if one exists, because this lets the compiler override
the underlying type if needed. */
if (type->target_type () != NULL && !type->target_type ()->is_stub ())
{
struct type *underlying_type = type->target_type ();
underlying_type = check_typedef (underlying_type);
type->set_is_unsigned (underlying_type->is_unsigned ());
if (type->length () == 0)
type->set_length (underlying_type->length ());
if (TYPE_RAW_ALIGN (type) == 0
&& TYPE_RAW_ALIGN (underlying_type) != 0)
set_type_align (type, TYPE_RAW_ALIGN (underlying_type));
}
type->set_is_declared_class (dwarf2_flag_true_p (die, DW_AT_enum_class, cu));
type->set_endianity_is_not_default (die_byte_order (die, cu, nullptr));
set_die_type (die, type, cu);
/* Finish the creation of this type by using the enum's children.
Note that, as usual, this must come after set_die_type to avoid
infinite recursion when trying to compute the names of the
enumerators. */
update_enumeration_type_from_children (die, type, cu);
return type;
}
/* Given a pointer to a die which begins an enumeration, process all
the dies that define the members of the enumeration, and create the
symbol for the enumeration type.
NOTE: We reverse the order of the element list. */
static void
process_enumeration_scope (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *this_type;
this_type = get_die_type (die, cu);
if (this_type == NULL)
this_type = read_enumeration_type (die, cu);
if (die->child != NULL)
{
struct die_info *child_die;
child_die = die->child;
while (child_die && child_die->tag)
{
if (child_die->tag != DW_TAG_enumerator)
{
process_die (child_die, cu);
}
else
new_symbol (child_die, this_type, cu);
child_die = child_die->sibling;
}
}
/* If we are reading an enum from a .debug_types unit, and the enum
is a declaration, and the enum is not the signatured type in the
unit, then we do not want to add a symbol for it. Adding a
symbol would in some cases obscure the true definition of the
enum, giving users an incomplete type when the definition is
actually available. Note that we do not want to do this for all
enums which are just declarations, because C++0x allows forward
enum declarations. */
if (cu->per_cu->is_debug_types
&& die_is_declaration (die, cu))
{
struct signatured_type *sig_type;
sig_type = (struct signatured_type *) cu->per_cu;
gdb_assert (to_underlying (sig_type->type_offset_in_section) != 0);
if (sig_type->type_offset_in_section != die->sect_off)
return;
}
new_symbol (die, this_type, cu);
}
/* Helper function for quirk_ada_thick_pointer that examines a bounds
expression for an index type and finds the corresponding field
offset in the hidden "P_BOUNDS" structure. Returns true on success
and updates *FIELD, false if it fails to recognize an
expression. */
static bool
recognize_bound_expression (struct die_info *die, enum dwarf_attribute name,
int *bounds_offset, struct field *field,
struct dwarf2_cu *cu)
{
struct attribute *attr = dwarf2_attr (die, name, cu);
if (attr == nullptr || !attr->form_is_block ())
return false;
const struct dwarf_block *block = attr->as_block ();
const gdb_byte *start = block->data;
const gdb_byte *end = block->data + block->size;
/* The expression to recognize generally looks like:
(DW_OP_push_object_address; DW_OP_plus_uconst: 8; DW_OP_deref;
DW_OP_plus_uconst: 4; DW_OP_deref_size: 4)
However, the second "plus_uconst" may be missing:
(DW_OP_push_object_address; DW_OP_plus_uconst: 8; DW_OP_deref;
DW_OP_deref_size: 4)
This happens when the field is at the start of the structure.
Also, the final deref may not be sized:
(DW_OP_push_object_address; DW_OP_plus_uconst: 4; DW_OP_deref;
DW_OP_deref)
This happens when the size of the index type happens to be the
same as the architecture's word size. This can occur with or
without the second plus_uconst. */
if (end - start < 2)
return false;
if (*start++ != DW_OP_push_object_address)
return false;
if (*start++ != DW_OP_plus_uconst)
return false;
uint64_t this_bound_off;
start = gdb_read_uleb128 (start, end, &this_bound_off);
if (start == nullptr || (int) this_bound_off != this_bound_off)
return false;
/* Update *BOUNDS_OFFSET if needed, or alternatively verify that it
is consistent among all bounds. */
if (*bounds_offset == -1)
*bounds_offset = this_bound_off;
else if (*bounds_offset != this_bound_off)
return false;
if (start == end || *start++ != DW_OP_deref)
return false;
int offset = 0;
if (start ==end)
return false;
else if (*start == DW_OP_deref_size || *start == DW_OP_deref)
{
/* This means an offset of 0. */
}
else if (*start++ != DW_OP_plus_uconst)
return false;
else
{
/* The size is the parameter to DW_OP_plus_uconst. */
uint64_t val;
start = gdb_read_uleb128 (start, end, &val);
if (start == nullptr)
return false;
if ((int) val != val)
return false;
offset = val;
}
if (start == end)
return false;
uint64_t size;
if (*start == DW_OP_deref_size)
{
start = gdb_read_uleb128 (start + 1, end, &size);
if (start == nullptr)
return false;
}
else if (*start == DW_OP_deref)
{
size = cu->header.addr_size;
++start;
}
else
return false;
field->set_loc_bitpos (8 * offset);
if (size != field->type ()->length ())
field->set_bitsize (8 * size);
return true;
}
/* With -fgnat-encodings=minimal, gcc will emit some unusual DWARF for
some kinds of Ada arrays:
<1><11db>: Abbrev Number: 7 (DW_TAG_array_type)
<11dc> DW_AT_name : (indirect string, offset: 0x1bb8): string
<11e0> DW_AT_data_location: 2 byte block: 97 6
(DW_OP_push_object_address; DW_OP_deref)
<11e3> DW_AT_type : <0x1173>
<11e7> DW_AT_sibling : <0x1201>
<2><11eb>: Abbrev Number: 8 (DW_TAG_subrange_type)
<11ec> DW_AT_type : <0x1206>
<11f0> DW_AT_lower_bound : 6 byte block: 97 23 8 6 94 4
(DW_OP_push_object_address; DW_OP_plus_uconst: 8; DW_OP_deref;
DW_OP_deref_size: 4)
<11f7> DW_AT_upper_bound : 8 byte block: 97 23 8 6 23 4 94 4
(DW_OP_push_object_address; DW_OP_plus_uconst: 8; DW_OP_deref;
DW_OP_plus_uconst: 4; DW_OP_deref_size: 4)
This actually represents a "thick pointer", which is a structure
with two elements: one that is a pointer to the array data, and one
that is a pointer to another structure; this second structure holds
the array bounds.
This returns a new type on success, or nullptr if this didn't
recognize the type. */
static struct type *
quirk_ada_thick_pointer (struct die_info *die, struct dwarf2_cu *cu,
struct type *type)
{
struct attribute *attr = dwarf2_attr (die, DW_AT_data_location, cu);
/* So far we've only seen this with block form. */
if (attr == nullptr || !attr->form_is_block ())
return nullptr;
/* Note that this will fail if the structure layout is changed by
the compiler. However, we have no good way to recognize some
other layout, because we don't know what expression the compiler
might choose to emit should this happen. */
struct dwarf_block *blk = attr->as_block ();
if (blk->size != 2
|| blk->data[0] != DW_OP_push_object_address
|| blk->data[1] != DW_OP_deref)
return nullptr;
int bounds_offset = -1;
int max_align = -1;
std::vector<struct field> range_fields;
for (struct die_info *child_die = die->child;
child_die;
child_die = child_die->sibling)
{
if (child_die->tag == DW_TAG_subrange_type)
{
struct type *underlying = read_subrange_index_type (child_die, cu);
int this_align = type_align (underlying);
if (this_align > max_align)
max_align = this_align;
range_fields.emplace_back ();
range_fields.emplace_back ();
struct field &lower = range_fields[range_fields.size () - 2];
struct field &upper = range_fields[range_fields.size () - 1];
lower.set_type (underlying);
lower.set_is_artificial (true);
upper.set_type (underlying);
upper.set_is_artificial (true);
if (!recognize_bound_expression (child_die, DW_AT_lower_bound,
&bounds_offset, &lower, cu)
|| !recognize_bound_expression (child_die, DW_AT_upper_bound,
&bounds_offset, &upper, cu))
return nullptr;
}
}
/* This shouldn't really happen, but double-check that we found
where the bounds are stored. */
if (bounds_offset == -1)
return nullptr;
struct objfile *objfile = cu->per_objfile->objfile;
for (int i = 0; i < range_fields.size (); i += 2)
{
char name[20];
/* Set the name of each field in the bounds. */
xsnprintf (name, sizeof (name), "LB%d", i / 2);
range_fields[i].set_name (objfile->intern (name));
xsnprintf (name, sizeof (name), "UB%d", i / 2);
range_fields[i + 1].set_name (objfile->intern (name));
}
type_allocator alloc (objfile, cu->lang ());
struct type *bounds = alloc.new_type ();
bounds->set_code (TYPE_CODE_STRUCT);
bounds->copy_fields (range_fields);
int last_fieldno = range_fields.size () - 1;
int bounds_size = (bounds->field (last_fieldno).loc_bitpos () / 8
+ bounds->field (last_fieldno).type ()->length ());
bounds->set_length (align_up (bounds_size, max_align));
/* Rewrite the existing array type in place. Specifically, we
remove any dynamic properties we might have read, and we replace
the index types. */
struct type *iter = type;
for (int i = 0; i < range_fields.size (); i += 2)
{
gdb_assert (iter->code () == TYPE_CODE_ARRAY);
iter->main_type->dyn_prop_list = nullptr;
iter->set_index_type
(create_static_range_type (alloc, bounds->field (i).type (), 1, 0));
iter = iter->target_type ();
}
struct type *result = type_allocator (objfile, cu->lang ()).new_type ();
result->set_code (TYPE_CODE_STRUCT);
result->alloc_fields (2);
/* The names are chosen to coincide with what the compiler does with
-fgnat-encodings=all, which the Ada code in gdb already
understands. */
result->field (0).set_name ("P_ARRAY");
result->field (0).set_type (lookup_pointer_type (type));
result->field (1).set_name ("P_BOUNDS");
result->field (1).set_type (lookup_pointer_type (bounds));
result->field (1).set_loc_bitpos (8 * bounds_offset);
result->set_name (type->name ());
result->set_length (result->field (0).type ()->length ()
+ result->field (1).type ()->length ());
return result;
}
/* Extract all information from a DW_TAG_array_type DIE and put it in
the DIE's type field. For now, this only handles one dimensional
arrays. */
static struct type *
read_array_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct die_info *child_die;
struct type *type;
struct type *element_type, *range_type, *index_type;
struct attribute *attr;
const char *name;
struct dynamic_prop *byte_stride_prop = NULL;
unsigned int bit_stride = 0;
element_type = die_type (die, cu);
/* The die_type call above may have already set the type for this DIE. */
type = get_die_type (die, cu);
if (type)
return type;
attr = dwarf2_attr (die, DW_AT_byte_stride, cu);
if (attr != NULL)
{
int stride_ok;
struct type *prop_type = cu->addr_sized_int_type (false);
byte_stride_prop
= (struct dynamic_prop *) alloca (sizeof (struct dynamic_prop));
stride_ok = attr_to_dynamic_prop (attr, die, cu, byte_stride_prop,
prop_type);
if (!stride_ok)
{
complaint (_("unable to read array DW_AT_byte_stride "
" - DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
/* Ignore this attribute. We will likely not be able to print
arrays of this type correctly, but there is little we can do
to help if we cannot read the attribute's value. */
byte_stride_prop = NULL;
}
}
attr = dwarf2_attr (die, DW_AT_bit_stride, cu);
if (attr != NULL)
bit_stride = attr->constant_value (0);
/* Irix 6.2 native cc creates array types without children for
arrays with unspecified length. */
if (die->child == NULL)
{
index_type = builtin_type (objfile)->builtin_int;
type_allocator alloc (objfile, cu->lang ());
range_type = create_static_range_type (alloc, index_type, 0, -1);
type = create_array_type_with_stride (alloc, element_type, range_type,
byte_stride_prop, bit_stride);
return set_die_type (die, type, cu);
}
std::vector<struct type *> range_types;
child_die = die->child;
while (child_die && child_die->tag)
{
if (child_die->tag == DW_TAG_subrange_type
|| child_die->tag == DW_TAG_generic_subrange)
{
struct type *child_type = read_type_die (child_die, cu);
if (child_type != NULL)
{
/* The range type was successfully read. Save it for the
array type creation. */
range_types.push_back (child_type);
}
}
child_die = child_die->sibling;
}
if (range_types.empty ())
{
complaint (_("unable to find array range - DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
return NULL;
}
/* Dwarf2 dimensions are output from left to right, create the
necessary array types in backwards order. */
type = element_type;
type_allocator alloc (cu->per_objfile->objfile, cu->lang ());
if (read_array_order (die, cu) == DW_ORD_col_major)
{
int i = 0;
while (i < range_types.size ())
{
type = create_array_type_with_stride (alloc, type, range_types[i++],
byte_stride_prop, bit_stride);
type->set_is_multi_dimensional (true);
bit_stride = 0;
byte_stride_prop = nullptr;
}
}
else
{
size_t ndim = range_types.size ();
while (ndim-- > 0)
{
type = create_array_type_with_stride (alloc, type, range_types[ndim],
byte_stride_prop, bit_stride);
type->set_is_multi_dimensional (true);
bit_stride = 0;
byte_stride_prop = nullptr;
}
}
/* Clear the flag on the outermost array type. */
type->set_is_multi_dimensional (false);
gdb_assert (type != element_type);
/* Understand Dwarf2 support for vector types (like they occur on
the PowerPC w/ AltiVec). Gcc just adds another attribute to the
array type. This is not part of the Dwarf2/3 standard yet, but a
custom vendor extension. The main difference between a regular
array and the vector variant is that vectors are passed by value
to functions. */
attr = dwarf2_attr (die, DW_AT_GNU_vector, cu);
if (attr != nullptr)
make_vector_type (type);
/* The DIE may have DW_AT_byte_size set. For example an OpenCL
implementation may choose to implement triple vectors using this
attribute. */
attr = dwarf2_attr (die, DW_AT_byte_size, cu);
if (attr != nullptr && attr->form_is_unsigned ())
{
if (attr->as_unsigned () >= type->length ())
type->set_length (attr->as_unsigned ());
else
complaint (_("DW_AT_byte_size for array type smaller "
"than the total size of elements"));
}
name = dwarf2_full_name (nullptr, die, cu);
if (name)
type->set_name (name);
maybe_set_alignment (cu, die, type);
struct type *replacement_type = nullptr;
if (cu->lang () == language_ada)
{
replacement_type = quirk_ada_thick_pointer (die, cu, type);
if (replacement_type != nullptr)
type = replacement_type;
}
/* Install the type in the die. */
set_die_type (die, type, cu, replacement_type != nullptr);
/* set_die_type should be already done. */
set_descriptive_type (type, die, cu);
return type;
}
static enum dwarf_array_dim_ordering
read_array_order (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr;
attr = dwarf2_attr (die, DW_AT_ordering, cu);
if (attr != nullptr)
{
std::optional<ULONGEST> val = attr->unsigned_constant ();
if (val.has_value () &&
(*val == DW_ORD_row_major || *val == DW_ORD_col_major))
return (enum dwarf_array_dim_ordering) *val;
}
/* GNU F77 is a special case, as at 08/2004 array type info is the
opposite order to the dwarf2 specification, but data is still
laid out as per normal fortran.
FIXME: dsl/2004-8-20: If G77 is ever fixed, this will also need
version checking. */
if (cu->lang () == language_fortran && cu->producer_is_gf77 ())
{
return DW_ORD_row_major;
}
switch (cu->language_defn->array_ordering ())
{
case array_column_major:
return DW_ORD_col_major;
case array_row_major:
default:
return DW_ORD_row_major;
};
}
/* Extract all information from a DW_TAG_set_type DIE and put it in
the DIE's type field. */
static struct type *
read_set_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *domain_type, *set_type;
struct attribute *attr;
domain_type = die_type (die, cu);
/* The die_type call above may have already set the type for this DIE. */
set_type = get_die_type (die, cu);
if (set_type)
return set_type;
type_allocator alloc (cu->per_objfile->objfile, cu->lang ());
set_type = create_set_type (alloc, domain_type);
attr = dwarf2_attr (die, DW_AT_byte_size, cu);
if (attr != nullptr && attr->form_is_unsigned ())
set_type->set_length (attr->as_unsigned ());
maybe_set_alignment (cu, die, set_type);
return set_die_type (die, set_type, cu);
}
/* A helper for read_common_block that creates a locexpr baton.
SYM is the symbol which we are marking as computed.
COMMON_DIE is the DIE for the common block.
COMMON_LOC is the location expression attribute for the common
block itself.
MEMBER_LOC is the location expression attribute for the particular
member of the common block that we are processing.
CU is the CU from which the above come. */
static void
mark_common_block_symbol_computed (struct symbol *sym,
struct die_info *common_die,
struct attribute *common_loc,
struct attribute *member_loc,
struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct dwarf2_locexpr_baton *baton;
gdb_byte *ptr;
unsigned int cu_off;
enum bfd_endian byte_order = gdbarch_byte_order (objfile->arch ());
LONGEST offset = 0;
gdb_assert (common_loc && member_loc);
gdb_assert (common_loc->form_is_block ());
gdb_assert (member_loc->form_is_block ()
|| member_loc->form_is_constant ());
baton = XOBNEW (&objfile->objfile_obstack, struct dwarf2_locexpr_baton);
baton->per_objfile = per_objfile;
baton->per_cu = cu->per_cu;
gdb_assert (baton->per_cu);
baton->size = 5 /* DW_OP_call4 */ + 1 /* DW_OP_plus */;
if (member_loc->form_is_constant ())
{
offset = member_loc->constant_value (0);
baton->size += 1 /* DW_OP_addr */ + cu->header.addr_size;
}
else
baton->size += member_loc->as_block ()->size;
ptr = (gdb_byte *) obstack_alloc (&objfile->objfile_obstack, baton->size);
baton->data = ptr;
*ptr++ = DW_OP_call4;
cu_off = common_die->sect_off - cu->per_cu->sect_off;
store_unsigned_integer (ptr, 4, byte_order, cu_off);
ptr += 4;
if (member_loc->form_is_constant ())
{
*ptr++ = DW_OP_addr;
store_unsigned_integer (ptr, cu->header.addr_size, byte_order, offset);
ptr += cu->header.addr_size;
}
else
{
/* We have to copy the data here, because DW_OP_call4 will only
use a DW_AT_location attribute. */
struct dwarf_block *block = member_loc->as_block ();
memcpy (ptr, block->data, block->size);
ptr += block->size;
}
*ptr++ = DW_OP_plus;
gdb_assert (ptr - baton->data == baton->size);
SYMBOL_LOCATION_BATON (sym) = baton;
sym->set_aclass_index (dwarf2_locexpr_index);
}
/* Create appropriate locally-scoped variables for all the
DW_TAG_common_block entries. Also create a struct common_block
listing all such variables for `info common'. COMMON_BLOCK_DOMAIN
is used to separate the common blocks name namespace from regular
variable names. */
static void
read_common_block (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr;
attr = dwarf2_attr (die, DW_AT_location, cu);
if (attr != nullptr)
{
/* Support the .debug_loc offsets. */
if (attr->form_is_block ())
{
/* Ok. */
}
else if (attr->form_is_section_offset ())
{
dwarf2_complex_location_expr_complaint ();
attr = NULL;
}
else
{
dwarf2_invalid_attrib_class_complaint ("DW_AT_location",
"common block member");
attr = NULL;
}
}
if (die->child != NULL)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct die_info *child_die;
size_t n_entries = 0, size;
struct common_block *common_block;
struct symbol *sym;
for (child_die = die->child;
child_die && child_die->tag;
child_die = child_die->sibling)
++n_entries;
size = (sizeof (struct common_block)
+ (n_entries - 1) * sizeof (struct symbol *));
common_block
= (struct common_block *) obstack_alloc (&objfile->objfile_obstack,
size);
memset (common_block->contents, 0, n_entries * sizeof (struct symbol *));
common_block->n_entries = 0;
for (child_die = die->child;
child_die && child_die->tag;
child_die = child_die->sibling)
{
/* Create the symbol in the DW_TAG_common_block block in the current
symbol scope. */
sym = new_symbol (child_die, NULL, cu);
if (sym != NULL)
{
struct attribute *member_loc;
common_block->contents[common_block->n_entries++] = sym;
member_loc = dwarf2_attr (child_die, DW_AT_data_member_location,
cu);
if (member_loc)
{
/* GDB has handled this for a long time, but it is
not specified by DWARF. It seems to have been
emitted by gfortran at least as recently as:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23057. */
complaint (_("Variable in common block has "
"DW_AT_data_member_location "
"- DIE at %s [in module %s]"),
sect_offset_str (child_die->sect_off),
objfile_name (objfile));
if (member_loc->form_is_section_offset ())
dwarf2_complex_location_expr_complaint ();
else if (member_loc->form_is_constant ()
|| member_loc->form_is_block ())
{
if (attr != nullptr)
mark_common_block_symbol_computed (sym, die, attr,
member_loc, cu);
}
else
dwarf2_complex_location_expr_complaint ();
}
}
}
sym = new_symbol (die, builtin_type (objfile)->builtin_void, cu);
sym->set_value_common_block (common_block);
}
}
/* Create a type for a C++ namespace. */
static struct type *
read_namespace_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
const char *previous_prefix, *name;
int is_anonymous;
struct type *type;
/* For extensions, reuse the type of the original namespace. */
if (dwarf2_attr (die, DW_AT_extension, cu) != NULL)
{
struct die_info *ext_die;
struct dwarf2_cu *ext_cu = cu;
ext_die = dwarf2_extension (die, &ext_cu);
type = read_type_die (ext_die, ext_cu);
/* EXT_CU may not be the same as CU.
Ensure TYPE is recorded with CU in die_type_hash. */
return set_die_type (die, type, cu);
}
name = namespace_name (die, &is_anonymous, cu);
/* Now build the name of the current namespace. */
previous_prefix = determine_prefix (die, cu);
gdb::unique_xmalloc_ptr<char> name_storage;
if (previous_prefix[0] != '\0')
{
name_storage = typename_concat (previous_prefix, name, 0, cu);
name = name_storage.get ();
}
/* Create the type. */
type = type_allocator (objfile, cu->lang ()).new_type (TYPE_CODE_NAMESPACE,
0, name);
return set_die_type (die, type, cu);
}
/* Read a namespace scope. */
static void
read_namespace (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
int is_anonymous;
/* Add a symbol associated to this if we haven't seen the namespace
before. Also, add a using directive if it's an anonymous
namespace. */
if (dwarf2_attr (die, DW_AT_extension, cu) == NULL)
{
struct type *type;
type = read_type_die (die, cu);
new_symbol (die, type, cu);
namespace_name (die, &is_anonymous, cu);
if (is_anonymous)
{
const char *previous_prefix = determine_prefix (die, cu);
std::vector<const char *> excludes;
add_using_directive (using_directives (cu),
previous_prefix, type->name (), NULL,
NULL, excludes,
read_decl_line (die, cu),
&objfile->objfile_obstack);
}
}
if (die->child != NULL)
{
struct die_info *child_die = die->child;
while (child_die && child_die->tag)
{
process_die (child_die, cu);
child_die = child_die->sibling;
}
}
}
/* Read a Fortran module or Ada package as type. For Fortran, This
DIE can be only a declaration used for imported module. Still we
need that type as local Fortran "use ... only" declaration imports
depend on the created type in determine_prefix. */
static struct type *
read_module_type (struct die_info *die, struct dwarf2_cu *cu)
{
enum language lang = cu->lang ();
struct objfile *objfile = cu->per_objfile->objfile;
struct type *type;
if (lang == language_ada)
{
const char *pkg_name = dwarf2_full_name (nullptr, die, cu);
type = type_allocator (objfile, lang).new_type (TYPE_CODE_NAMESPACE,
0, pkg_name);
}
else
{
const char *module_name = dwarf2_name (die, cu);
type = type_allocator (objfile, lang).new_type (TYPE_CODE_MODULE,
0, module_name);
}
return set_die_type (die, type, cu);
}
/* Read a module. This tag is used by Fortran (for modules), but also
by Ada (for packages). */
static void
read_module (struct die_info *die, struct dwarf2_cu *cu)
{
struct die_info *child_die = die->child;
struct type *type;
type = read_type_die (die, cu);
new_symbol (die, type, cu);
while (child_die && child_die->tag)
{
process_die (child_die, cu);
child_die = child_die->sibling;
}
}
/* Return the name of the namespace represented by DIE. Set
*IS_ANONYMOUS to tell whether or not the namespace is an anonymous
namespace. */
static const char *
namespace_name (struct die_info *die, int *is_anonymous, struct dwarf2_cu *cu)
{
struct die_info *current_die;
const char *name = NULL;
/* Loop through the extensions until we find a name. */
for (current_die = die;
current_die != NULL;
current_die = dwarf2_extension (die, &cu))
{
/* We don't use dwarf2_name here so that we can detect the absence
of a name -> anonymous namespace. */
name = dwarf2_string_attr (die, DW_AT_name, cu);
if (name != NULL)
break;
}
/* Is it an anonymous namespace? */
*is_anonymous = (name == NULL);
if (*is_anonymous)
name = CP_ANONYMOUS_NAMESPACE_STR;
return name;
}
/* Extract all information from a DW_TAG_pointer_type DIE and add to
the user defined type vector. */
static struct type *
read_tag_pointer_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct gdbarch *gdbarch = cu->per_objfile->objfile->arch ();
struct comp_unit_head *cu_header = &cu->header;
struct type *type;
struct attribute *attr_byte_size;
struct attribute *attr_address_class;
int byte_size;
struct type *target_type;
target_type = die_type (die, cu);
/* The die_type call above may have already set the type for this DIE. */
type = get_die_type (die, cu);
if (type)
return type;
type = lookup_pointer_type (target_type);
attr_byte_size = dwarf2_attr (die, DW_AT_byte_size, cu);
if (attr_byte_size)
byte_size = attr_byte_size->constant_value (cu_header->addr_size);
else
byte_size = cu_header->addr_size;
attr_address_class = dwarf2_attr (die, DW_AT_address_class, cu);
ULONGEST addr_class;
if (attr_address_class)
addr_class = (attr_address_class->unsigned_constant ()
.value_or (DW_ADDR_none));
else
addr_class = DW_ADDR_none;
ULONGEST alignment = get_alignment (cu, die);
/* If the pointer size, alignment, or address class is different
than the default, create a type variant marked as such and set
the length accordingly. */
if (type->length () != byte_size
|| (alignment != 0 && TYPE_RAW_ALIGN (type) != 0
&& alignment != TYPE_RAW_ALIGN (type))
|| addr_class != DW_ADDR_none)
{
if (gdbarch_address_class_type_flags_p (gdbarch))
{
type_instance_flags type_flags
= gdbarch_address_class_type_flags (gdbarch, byte_size,
addr_class);
gdb_assert ((type_flags & ~TYPE_INSTANCE_FLAG_ADDRESS_CLASS_ALL)
== 0);
type = make_type_with_address_space (type, type_flags);
}
else if (type->length () != byte_size)
{
complaint (_("invalid pointer size %d"), byte_size);
}
else if (TYPE_RAW_ALIGN (type) != alignment)
{
complaint (_("Invalid DW_AT_alignment"
" - DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
}
else
{
/* Should we also complain about unhandled address classes? */
}
}
type->set_length (byte_size);
set_type_align (type, alignment);
return set_die_type (die, type, cu);
}
/* Extract all information from a DW_TAG_ptr_to_member_type DIE and add to
the user defined type vector. */
static struct type *
read_tag_ptr_to_member_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *type;
struct type *to_type;
struct type *domain;
to_type = die_type (die, cu);
domain = die_containing_type (die, cu);
/* The calls above may have already set the type for this DIE. */
type = get_die_type (die, cu);
if (type)
return type;
if (check_typedef (to_type)->code () == TYPE_CODE_METHOD)
type = lookup_methodptr_type (to_type);
else if (check_typedef (to_type)->code () == TYPE_CODE_FUNC)
{
struct type *new_type
= type_allocator (cu->per_objfile->objfile, cu->lang ()).new_type ();
smash_to_method_type (new_type, domain, to_type->target_type (),
to_type->fields (), to_type->num_fields (),
to_type->has_varargs ());
type = lookup_methodptr_type (new_type);
}
else
type = lookup_memberptr_type (to_type, domain);
return set_die_type (die, type, cu);
}
/* Extract all information from a DW_TAG_{rvalue_,}reference_type DIE and add to
the user defined type vector. */
static struct type *
read_tag_reference_type (struct die_info *die, struct dwarf2_cu *cu,
enum type_code refcode)
{
struct comp_unit_head *cu_header = &cu->header;
struct type *type, *target_type;
struct attribute *attr;
gdb_assert (refcode == TYPE_CODE_REF || refcode == TYPE_CODE_RVALUE_REF);
target_type = die_type (die, cu);
/* The die_type call above may have already set the type for this DIE. */
type = get_die_type (die, cu);
if (type)
return type;
type = lookup_reference_type (target_type, refcode);
attr = dwarf2_attr (die, DW_AT_byte_size, cu);
if (attr != nullptr)
type->set_length (attr->constant_value (cu_header->addr_size));
else
type->set_length (cu_header->addr_size);
maybe_set_alignment (cu, die, type);
return set_die_type (die, type, cu);
}
/* Add the given cv-qualifiers to the element type of the array. GCC
outputs DWARF type qualifiers that apply to an array, not the
element type. But GDB relies on the array element type to carry
the cv-qualifiers. This mimics section 6.7.3 of the C99
specification. */
static struct type *
add_array_cv_type (struct die_info *die, struct dwarf2_cu *cu,
struct type *base_type, int cnst, int voltl)
{
struct type *el_type, *inner_array;
base_type = copy_type (base_type);
inner_array = base_type;
while (inner_array->target_type ()->code () == TYPE_CODE_ARRAY)
{
inner_array->set_target_type (copy_type (inner_array->target_type ()));
inner_array = inner_array->target_type ();
}
el_type = inner_array->target_type ();
cnst |= TYPE_CONST (el_type);
voltl |= TYPE_VOLATILE (el_type);
inner_array->set_target_type (make_cv_type (cnst, voltl, el_type, NULL));
return set_die_type (die, base_type, cu);
}
static struct type *
read_tag_const_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *base_type, *cv_type;
base_type = die_type (die, cu);
/* The die_type call above may have already set the type for this DIE. */
cv_type = get_die_type (die, cu);
if (cv_type)
return cv_type;
/* In case the const qualifier is applied to an array type, the element type
is so qualified, not the array type (section 6.7.3 of C99). */
if (base_type->code () == TYPE_CODE_ARRAY)
return add_array_cv_type (die, cu, base_type, 1, 0);
cv_type = make_cv_type (1, TYPE_VOLATILE (base_type), base_type, 0);
return set_die_type (die, cv_type, cu);
}
static struct type *
read_tag_volatile_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *base_type, *cv_type;
base_type = die_type (die, cu);
/* The die_type call above may have already set the type for this DIE. */
cv_type = get_die_type (die, cu);
if (cv_type)
return cv_type;
/* In case the volatile qualifier is applied to an array type, the
element type is so qualified, not the array type (section 6.7.3
of C99). */
if (base_type->code () == TYPE_CODE_ARRAY)
return add_array_cv_type (die, cu, base_type, 0, 1);
cv_type = make_cv_type (TYPE_CONST (base_type), 1, base_type, 0);
return set_die_type (die, cv_type, cu);
}
/* Handle DW_TAG_restrict_type. */
static struct type *
read_tag_restrict_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *base_type, *cv_type;
base_type = die_type (die, cu);
/* The die_type call above may have already set the type for this DIE. */
cv_type = get_die_type (die, cu);
if (cv_type)
return cv_type;
cv_type = make_restrict_type (base_type);
return set_die_type (die, cv_type, cu);
}
/* Handle DW_TAG_atomic_type. */
static struct type *
read_tag_atomic_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *base_type, *cv_type;
base_type = die_type (die, cu);
/* The die_type call above may have already set the type for this DIE. */
cv_type = get_die_type (die, cu);
if (cv_type)
return cv_type;
cv_type = make_atomic_type (base_type);
return set_die_type (die, cv_type, cu);
}
/* Extract all information from a DW_TAG_string_type DIE and add to
the user defined type vector. It isn't really a user defined type,
but it behaves like one, with other DIE's using an AT_user_def_type
attribute to reference it. */
static struct type *
read_tag_string_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct gdbarch *gdbarch = objfile->arch ();
struct type *type, *range_type, *index_type, *char_type;
struct attribute *attr;
struct dynamic_prop prop;
bool length_is_constant = true;
LONGEST length;
/* There are a couple of places where bit sizes might be made use of
when parsing a DW_TAG_string_type, however, no producer that we know
of make use of these. Handling bit sizes that are a multiple of the
byte size is easy enough, but what about other bit sizes? Lets deal
with that problem when we have to. Warn about these attributes being
unsupported, then parse the type and ignore them like we always
have. */
if (dwarf2_attr (die, DW_AT_bit_size, cu) != nullptr
|| dwarf2_attr (die, DW_AT_string_length_bit_size, cu) != nullptr)
{
static bool warning_printed = false;
if (!warning_printed)
{
warning (_("DW_AT_bit_size and DW_AT_string_length_bit_size not "
"currently supported on DW_TAG_string_type."));
warning_printed = true;
}
}
attr = dwarf2_attr (die, DW_AT_string_length, cu);
if (attr != nullptr && !attr->form_is_constant ())
{
/* The string length describes the location at which the length of
the string can be found. The size of the length field can be
specified with one of the attributes below. */
struct type *prop_type;
struct attribute *len
= dwarf2_attr (die, DW_AT_string_length_byte_size, cu);
if (len == nullptr)
len = dwarf2_attr (die, DW_AT_byte_size, cu);
if (len != nullptr && len->form_is_constant ())
{
/* Pass 0 as the default as we know this attribute is constant
and the default value will not be returned. */
LONGEST sz = len->constant_value (0);
prop_type = objfile_int_type (objfile, sz, true);
}
else
{
/* If the size is not specified then we assume it is the size of
an address on this target. */
prop_type = cu->addr_sized_int_type (true);
}
/* Convert the attribute into a dynamic property. */
if (!attr_to_dynamic_prop (attr, die, cu, &prop, prop_type))
length = 1;
else
length_is_constant = false;
}
else if (attr != nullptr)
{
/* This DW_AT_string_length just contains the length with no
indirection. There's no need to create a dynamic property in this
case. Pass 0 for the default value as we know it will not be
returned in this case. */
length = attr->constant_value (0);
}
else if ((attr = dwarf2_attr (die, DW_AT_byte_size, cu)) != nullptr)
{
/* We don't currently support non-constant byte sizes for strings. */
length = attr->constant_value (1);
}
else
{
/* Use 1 as a fallback length if we have nothing else. */
length = 1;
}
index_type = builtin_type (objfile)->builtin_int;
type_allocator alloc (objfile, cu->lang ());
if (length_is_constant)
range_type = create_static_range_type (alloc, index_type, 1, length);
else
{
struct dynamic_prop low_bound;
low_bound.set_const_val (1);
range_type = create_range_type (alloc, index_type, &low_bound, &prop, 0);
}
char_type = language_string_char_type (cu->language_defn, gdbarch);
type = create_string_type (alloc, char_type, range_type);
return set_die_type (die, type, cu);
}
/* Assuming that DIE corresponds to a function, returns nonzero
if the function is prototyped. */
static int
prototyped_function_p (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr;
attr = dwarf2_attr (die, DW_AT_prototyped, cu);
if (attr && attr->as_boolean ())
return 1;
/* The DWARF standard implies that the DW_AT_prototyped attribute
is only meaningful for C, but the concept also extends to other
languages that allow unprototyped functions (Eg: Objective C).
For all other languages, assume that functions are always
prototyped. */
if (cu->lang () != language_c
&& cu->lang () != language_objc
&& cu->lang () != language_opencl)
return 1;
/* RealView does not emit DW_AT_prototyped. We can not distinguish
prototyped and unprototyped functions; default to prototyped,
since that is more common in modern code (and RealView warns
about unprototyped functions). */
if (cu->producer_is_realview ())
return 1;
return 0;
}
/* Handle DIES due to C code like:
struct foo
{
int (*funcp)(int a, long l);
int b;
};
('funcp' generates a DW_TAG_subroutine_type DIE). */
static struct type *
read_subroutine_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct type *type; /* Type that this function returns. */
struct type *ftype; /* Function that returns above type. */
struct attribute *attr;
type = die_type (die, cu);
/* PR gas/29517 occurs in 2.39, and is fixed in 2.40, but it's only fixed
for dwarf version >= 3 which supports DW_TAG_unspecified_type. */
if (type->code () == TYPE_CODE_VOID
&& !type->is_stub ()
&& die->child == nullptr
&& (cu->header.version == 2 || cu->producer_is_gas_2_39 ()))
{
/* Work around PR gas/29517, pretend we have an DW_TAG_unspecified_type
return type. */
type = (type_allocator (cu->per_objfile->objfile, cu->lang ())
.new_type (TYPE_CODE_VOID, 0, nullptr));
type->set_is_stub (true);
}
/* The die_type call above may have already set the type for this DIE. */
ftype = get_die_type (die, cu);
if (ftype)
return ftype;
ftype = lookup_function_type (type);
if (prototyped_function_p (die, cu))
ftype->set_is_prototyped (true);
/* Store the calling convention in the type if it's available in
the subroutine die. Otherwise set the calling convention to
the default value DW_CC_normal. */
attr = dwarf2_attr (die, DW_AT_calling_convention, cu);
if (attr != nullptr)
{
std::optional<ULONGEST> value = attr->unsigned_constant ();
if (value.has_value ()
&& is_valid_DW_AT_calling_convention_for_subroutine (*value))
TYPE_CALLING_CONVENTION (ftype)
= (enum dwarf_calling_convention) *value;
}
else if (cu->producer_is_xlc_opencl ())
TYPE_CALLING_CONVENTION (ftype) = DW_CC_GDB_IBM_OpenCL;
else
TYPE_CALLING_CONVENTION (ftype) = DW_CC_normal;
/* Record whether the function returns normally to its caller or not
if the DWARF producer set that information. */
attr = dwarf2_attr (die, DW_AT_noreturn, cu);
if (attr && attr->as_boolean ())
TYPE_NO_RETURN (ftype) = 1;
/* We need to add the subroutine type to the die immediately so
we don't infinitely recurse when dealing with parameters
declared as the same subroutine type. */
set_die_type (die, ftype, cu);
if (die->child != NULL)
{
struct type *void_type = builtin_type (objfile)->builtin_void;
struct die_info *child_die;
int nparams, iparams;
/* Count the number of parameters.
FIXME: GDB currently ignores vararg functions, but knows about
vararg member functions. */
nparams = 0;
child_die = die->child;
while (child_die && child_die->tag)
{
if (child_die->tag == DW_TAG_formal_parameter)
nparams++;
else if (child_die->tag == DW_TAG_unspecified_parameters)
ftype->set_has_varargs (true);
child_die = child_die->sibling;
}
/* Allocate storage for parameters and fill them in. */
ftype->alloc_fields (nparams);
/* TYPE_FIELD_TYPE must never be NULL. Pre-fill the array to ensure it
even if we error out during the parameters reading below. */
for (iparams = 0; iparams < nparams; iparams++)
ftype->field (iparams).set_type (void_type);
iparams = 0;
child_die = die->child;
while (child_die && child_die->tag)
{
if (child_die->tag == DW_TAG_formal_parameter)
{
struct type *arg_type;
/* DWARF version 2 has no clean way to discern C++
static and non-static member functions. G++ helps
GDB by marking the first parameter for non-static
member functions (which is the this pointer) as
artificial. We pass this information to
dwarf2_add_member_fn via TYPE_FIELD_ARTIFICIAL.
DWARF version 3 added DW_AT_object_pointer, which GCC
4.5 does not yet generate. */
attr = dwarf2_attr (child_die, DW_AT_artificial, cu);
if (attr != nullptr)
ftype->field (iparams).set_is_artificial (attr->as_boolean ());
else
ftype->field (iparams).set_is_artificial (false);
arg_type = die_type (child_die, cu);
/* RealView does not mark THIS as const, which the testsuite
expects. GCC marks THIS as const in method definitions,
but not in the class specifications (GCC PR 43053). */
if (cu->lang () == language_cplus
&& !TYPE_CONST (arg_type)
&& ftype->field (iparams).is_artificial ())
{
int is_this = 0;
struct dwarf2_cu *arg_cu = cu;
const char *name = dwarf2_name (child_die, cu);
attr = dwarf2_attr (die, DW_AT_object_pointer, cu);
if (attr != nullptr)
{
/* If the compiler emits this, use it. */
if (follow_die_ref (die, attr, &arg_cu) == child_die)
is_this = 1;
}
else if (name && strcmp (name, "this") == 0)
/* Function definitions will have the argument names. */
is_this = 1;
else if (name == NULL && iparams == 0)
/* Declarations may not have the names, so like
elsewhere in GDB, assume an artificial first
argument is "this". */
is_this = 1;
if (is_this)
arg_type = make_cv_type (1, TYPE_VOLATILE (arg_type),
arg_type, 0);
}
ftype->field (iparams).set_type (arg_type);
iparams++;
}
child_die = child_die->sibling;
}
}
return ftype;
}
static struct type *
read_typedef (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
const char *name = dwarf2_full_name (NULL, die, cu);
struct type *this_type;
struct gdbarch *gdbarch = objfile->arch ();
struct type *target_type = die_type (die, cu);
if (gdbarch_dwarf2_omit_typedef_p (gdbarch, target_type,
cu->get_producer (), name))
{
/* The long double is defined as a base type in C. GCC creates a long
double typedef with target-type _Float128 for the long double to
identify it as the IEEE Float128 value. This is a GCC hack since the
DWARF doesn't distinguish between the IBM long double and IEEE
128-bit float. Replace the GCC workaround for the long double
typedef with the actual type information copied from the target-type
with the correct long double base type name. */
this_type = copy_type (target_type);
this_type->set_name (name);
set_die_type (die, this_type, cu);
return this_type;
}
type_allocator alloc (objfile, cu->lang ());
this_type = alloc.new_type (TYPE_CODE_TYPEDEF, 0, name);
this_type->set_target_is_stub (true);
set_die_type (die, this_type, cu);
if (target_type != this_type)
this_type->set_target_type (target_type);
else
{
/* Self-referential typedefs are, it seems, not allowed by the DWARF
spec and cause infinite loops in GDB. */
complaint (_("Self-referential DW_TAG_typedef "
"- DIE at %s [in module %s]"),
sect_offset_str (die->sect_off), objfile_name (objfile));
this_type->set_target_type (nullptr);
}
if (name == NULL)
{
/* Gcc-7 and before supports -feliminate-dwarf2-dups, which generates
anonymous typedefs, which is, strictly speaking, invalid DWARF.
Handle these by just returning the target type, rather than
constructing an anonymous typedef type and trying to handle this
elsewhere. */
set_die_type (die, target_type, cu);
return target_type;
}
return this_type;
}
/* Helper for get_dwarf2_rational_constant that computes the value of
a given gmp_mpz given an attribute. */
static void
get_mpz (struct dwarf2_cu *cu, gdb_mpz *value, struct attribute *attr)
{
/* GCC will sometimes emit a 16-byte constant value as a DWARF
location expression that pushes an implicit value. */
if (attr->form == DW_FORM_exprloc)
{
dwarf_block *blk = attr->as_block ();
if (blk->size > 0 && blk->data[0] == DW_OP_implicit_value)
{
uint64_t len;
const gdb_byte *ptr = safe_read_uleb128 (blk->data + 1,
blk->data + blk->size,
&len);
if (ptr - blk->data + len <= blk->size)
{
value->read (gdb::make_array_view (ptr, len),
bfd_big_endian (cu->per_objfile->objfile->obfd.get ())
? BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE,
true);
return;
}
}
/* On failure set it to 1. */
*value = gdb_mpz (1);
}
else if (attr->form_is_block ())
{
dwarf_block *blk = attr->as_block ();
value->read (gdb::make_array_view (blk->data, blk->size),
bfd_big_endian (cu->per_objfile->objfile->obfd.get ())
? BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE,
true);
}
else if (attr->form_is_unsigned ())
*value = gdb_mpz (attr->as_unsigned ());
else
*value = gdb_mpz (attr->constant_value (1));
}
/* Assuming DIE is a rational DW_TAG_constant, read the DIE's
numerator and denominator into NUMERATOR and DENOMINATOR (resp).
If the numerator and/or numerator attribute is missing,
a complaint is filed, and NUMERATOR and DENOMINATOR are left
untouched. */
static void
get_dwarf2_rational_constant (struct die_info *die, struct dwarf2_cu *cu,
gdb_mpz *numerator, gdb_mpz *denominator)
{
struct attribute *num_attr, *denom_attr;
num_attr = dwarf2_attr (die, DW_AT_GNU_numerator, cu);
if (num_attr == nullptr)
complaint (_("DW_AT_GNU_numerator missing in %s DIE at %s"),
dwarf_tag_name (die->tag), sect_offset_str (die->sect_off));
denom_attr = dwarf2_attr (die, DW_AT_GNU_denominator, cu);
if (denom_attr == nullptr)
complaint (_("DW_AT_GNU_denominator missing in %s DIE at %s"),
dwarf_tag_name (die->tag), sect_offset_str (die->sect_off));
if (num_attr == nullptr || denom_attr == nullptr)
return;
get_mpz (cu, numerator, num_attr);
get_mpz (cu, denominator, denom_attr);
}
/* Same as get_dwarf2_rational_constant, but extracting an unsigned
rational constant, rather than a signed one.
If the rational constant has a negative value, a complaint
is filed, and NUMERATOR and DENOMINATOR are left untouched. */
static void
get_dwarf2_unsigned_rational_constant (struct die_info *die,
struct dwarf2_cu *cu,
gdb_mpz *numerator,
gdb_mpz *denominator)
{
gdb_mpz num (1);
gdb_mpz denom (1);
get_dwarf2_rational_constant (die, cu, &num, &denom);
if (num < 0 && denom < 0)
{
num.negate ();
denom.negate ();
}
else if (num < 0)
{
complaint (_("unexpected negative value for DW_AT_GNU_numerator"
" in DIE at %s"),
sect_offset_str (die->sect_off));
return;
}
else if (denom < 0)
{
complaint (_("unexpected negative value for DW_AT_GNU_denominator"
" in DIE at %s"),
sect_offset_str (die->sect_off));
return;
}
*numerator = std::move (num);
*denominator = std::move (denom);
}
/* Assuming that ENCODING is a string whose contents starting at the
K'th character is "_nn" where "nn" is a decimal number, scan that
number and set RESULT to the value. K is updated to point to the
character immediately following the number.
If the string does not conform to the format described above, false
is returned, and K may or may not be changed. */
static bool
ada_get_gnat_encoded_number (const char *encoding, int &k, gdb_mpz *result)
{
/* The next character should be an underscore ('_') followed
by a digit. */
if (encoding[k] != '_' || !isdigit (encoding[k + 1]))
return false;
/* Skip the underscore. */
k++;
int start = k;
/* Determine the number of digits for our number. */
while (isdigit (encoding[k]))
k++;
if (k == start)
return false;
std::string copy (&encoding[start], k - start);
return result->set (copy.c_str (), 10);
}
/* Scan two numbers from ENCODING at OFFSET, assuming the string is of
the form _NN_DD, where NN and DD are decimal numbers. Set NUM and
DENOM, update OFFSET, and return true on success. Return false on
failure. */
static bool
ada_get_gnat_encoded_ratio (const char *encoding, int &offset,
gdb_mpz *num, gdb_mpz *denom)
{
if (!ada_get_gnat_encoded_number (encoding, offset, num))
return false;
return ada_get_gnat_encoded_number (encoding, offset, denom);
}
/* Assuming DIE corresponds to a fixed point type, finish the creation
of the corresponding TYPE by setting its type-specific data. CU is
the DIE's CU. SUFFIX is the "XF" type name suffix coming from GNAT
encodings. It is nullptr if the GNAT encoding should be
ignored. */
static void
finish_fixed_point_type (struct type *type, const char *suffix,
struct die_info *die, struct dwarf2_cu *cu)
{
gdb_assert (type->code () == TYPE_CODE_FIXED_POINT
&& TYPE_SPECIFIC_FIELD (type) == TYPE_SPECIFIC_FIXED_POINT);
/* If GNAT encodings are preferred, don't examine the
attributes. */
struct attribute *attr = nullptr;
if (suffix == nullptr)
{
attr = dwarf2_attr (die, DW_AT_binary_scale, cu);
if (attr == nullptr)
attr = dwarf2_attr (die, DW_AT_decimal_scale, cu);
if (attr == nullptr)
attr = dwarf2_attr (die, DW_AT_small, cu);
}
/* Numerator and denominator of our fixed-point type's scaling factor.
The default is a scaling factor of 1, which we use as a fallback
when we are not able to decode it (problem with the debugging info,
unsupported forms, bug in GDB, etc...). Using that as the default
allows us to at least print the unscaled value, which might still
be useful to a user. */
gdb_mpz scale_num (1);
gdb_mpz scale_denom (1);
if (attr == nullptr)
{
int offset = 0;
if (suffix != nullptr
&& ada_get_gnat_encoded_ratio (suffix, offset, &scale_num,
&scale_denom)
/* The number might be encoded as _nn_dd_nn_dd, where the
second ratio is the 'small value. In this situation, we
want the second value. */
&& (suffix[offset] != '_'
|| ada_get_gnat_encoded_ratio (suffix, offset, &scale_num,
&scale_denom)))
{
/* Found it. */
}
else
{
/* Scaling factor not found. Assume a scaling factor of 1,
and hope for the best. At least the user will be able to
see the encoded value. */
scale_num = 1;
scale_denom = 1;
complaint (_("no scale found for fixed-point type (DIE at %s)"),
sect_offset_str (die->sect_off));
}
}
else if (attr->name == DW_AT_binary_scale)
{
LONGEST scale_exp = attr->constant_value (0);
gdb_mpz &num_or_denom = scale_exp > 0 ? scale_num : scale_denom;
num_or_denom <<= std::abs (scale_exp);
}
else if (attr->name == DW_AT_decimal_scale)
{
LONGEST scale_exp = attr->constant_value (0);
gdb_mpz &num_or_denom = scale_exp > 0 ? scale_num : scale_denom;
num_or_denom = gdb_mpz::pow (10, std::abs (scale_exp));
}
else if (attr->name == DW_AT_small)
{
struct die_info *scale_die;
struct dwarf2_cu *scale_cu = cu;
scale_die = follow_die_ref (die, attr, &scale_cu);
if (scale_die->tag == DW_TAG_constant)
get_dwarf2_unsigned_rational_constant (scale_die, scale_cu,
&scale_num, &scale_denom);
else
complaint (_("%s DIE not supported as target of DW_AT_small attribute"
" (DIE at %s)"),
dwarf_tag_name (die->tag), sect_offset_str (die->sect_off));
}
else
{
complaint (_("unsupported scale attribute %s for fixed-point type"
" (DIE at %s)"),
dwarf_attr_name (attr->name),
sect_offset_str (die->sect_off));
}
type->fixed_point_info ().scaling_factor = gdb_mpq (scale_num, scale_denom);
}
/* The gnat-encoding suffix for fixed point. */
#define GNAT_FIXED_POINT_SUFFIX "___XF_"
/* If NAME encodes an Ada fixed-point type, return a pointer to the
"XF" suffix of the name. The text after this is what encodes the
'small and 'delta information. Otherwise, return nullptr. */
static const char *
gnat_encoded_fixed_point_type_info (const char *name)
{
return strstr (name, GNAT_FIXED_POINT_SUFFIX);
}
/* Allocate a floating-point type of size BITS and name NAME. Pass NAME_HINT
(which may be different from NAME) to the architecture back-end to allow
it to guess the correct format if necessary. */
static struct type *
dwarf2_init_float_type (struct dwarf2_cu *cu, int bits, const char *name,
const char *name_hint, enum bfd_endian byte_order)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct gdbarch *gdbarch = objfile->arch ();
const struct floatformat **format;
struct type *type;
type_allocator alloc (objfile, cu->lang ());
format = gdbarch_floatformat_for_type (gdbarch, name_hint, bits);
if (format)
type = init_float_type (alloc, bits, name, format, byte_order);
else
type = alloc.new_type (TYPE_CODE_ERROR, bits, name);
return type;
}
/* Allocate an integer type of size BITS and name NAME. */
static struct type *
dwarf2_init_integer_type (struct dwarf2_cu *cu, int bits, int unsigned_p,
const char *name)
{
struct type *type;
struct objfile *objfile = cu->per_objfile->objfile;
/* Versions of Intel's C Compiler generate an integer type called "void"
instead of using DW_TAG_unspecified_type. This has been seen on
at least versions 14, 17, and 18. */
if (bits == 0 && cu->producer_is_icc () && name != nullptr
&& strcmp (name, "void") == 0)
type = builtin_type (objfile)->builtin_void;
else
{
type_allocator alloc (objfile, cu->lang ());
type = init_integer_type (alloc, bits, unsigned_p, name);
}
return type;
}
/* Return true if DIE has a DW_AT_small attribute whose value is
a constant rational, where both the numerator and denominator
are equal to zero.
CU is the DIE's Compilation Unit. */
static bool
has_zero_over_zero_small_attribute (struct die_info *die,
struct dwarf2_cu *cu)
{
struct attribute *attr = dwarf2_attr (die, DW_AT_small, cu);
if (attr == nullptr)
return false;
struct dwarf2_cu *scale_cu = cu;
struct die_info *scale_die
= follow_die_ref (die, attr, &scale_cu);
if (scale_die->tag != DW_TAG_constant)
return false;
gdb_mpz num (1), denom (1);
get_dwarf2_rational_constant (scale_die, cu, &num, &denom);
return num == 0 && denom == 0;
}
/* Initialise and return a floating point type of size BITS suitable for
use as a component of a complex number. The NAME_HINT is passed through
when initialising the floating point type and is the name of the complex
type.
As DWARF doesn't currently provide an explicit name for the components
of a complex number, but it can be helpful to have these components
named, we try to select a suitable name based on the size of the
component. */
static struct type *
dwarf2_init_complex_target_type (struct dwarf2_cu *cu,
int bits, const char *name_hint,
enum bfd_endian byte_order)
{
struct objfile *objfile = cu->per_objfile->objfile;
gdbarch *gdbarch = objfile->arch ();
struct type *tt = nullptr;
/* Try to find a suitable floating point builtin type of size BITS.
We're going to use the name of this type as the name for the complex
target type that we are about to create. */
switch (cu->lang ())
{
case language_fortran:
switch (bits)
{
case 32:
tt = builtin_f_type (gdbarch)->builtin_real;
break;
case 64:
tt = builtin_f_type (gdbarch)->builtin_real_s8;
break;
case 96: /* The x86-32 ABI specifies 96-bit long double. */
case 128:
tt = builtin_f_type (gdbarch)->builtin_real_s16;
break;
}
break;
default:
switch (bits)
{
case 32:
tt = builtin_type (gdbarch)->builtin_float;
break;
case 64:
if (builtin_type (gdbarch)->builtin_long_double->length () == 8
&& name_hint != nullptr
&& strstr (name_hint, "long") != nullptr)
{
/* Use "long double" for "complex long double". */
tt = builtin_type (gdbarch)->builtin_long_double;
}
else
tt = builtin_type (gdbarch)->builtin_double;
break;
case 96: /* The x86-32 ABI specifies 96-bit long double. */
case 128:
tt = builtin_type (gdbarch)->builtin_long_double;
break;
}
break;
}
/* If the type we found doesn't match the size we were looking for, then
pretend we didn't find a type at all, the complex target type we
create will then be nameless. */
if (tt != nullptr && tt->length () * TARGET_CHAR_BIT != bits)
tt = nullptr;
const char *name = (tt == nullptr) ? nullptr : tt->name ();
return dwarf2_init_float_type (cu, bits, name, name_hint, byte_order);
}
/* Find a representation of a given base type and install
it in the TYPE field of the die. */
static struct type *
read_base_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct type *type;
struct attribute *attr;
ULONGEST encoding = 0;
int bits = 0;
const char *name;
attr = dwarf2_attr (die, DW_AT_encoding, cu);
if (attr != nullptr)
{
std::optional<ULONGEST> value = attr->unsigned_constant ();
if (value.has_value ())
encoding = *value;
}
attr = dwarf2_attr (die, DW_AT_byte_size, cu);
if (attr != nullptr)
bits = attr->constant_value (0) * TARGET_CHAR_BIT;
name = dwarf2_full_name (nullptr, die, cu);
if (!name)
complaint (_("DW_AT_name missing from DW_TAG_base_type"));
enum bfd_endian byte_order;
bool not_default = die_byte_order (die, cu, &byte_order);
if ((encoding == DW_ATE_signed_fixed || encoding == DW_ATE_unsigned_fixed)
&& cu->lang () == language_ada
&& has_zero_over_zero_small_attribute (die, cu))
{
/* brobecker/2018-02-24: This is a fixed point type for which
the scaling factor is represented as fraction whose value
does not make sense (zero divided by zero), so we should
normally never see these. However, there is a small category
of fixed point types for which GNAT is unable to provide
the scaling factor via the standard DWARF mechanisms, and
for which the info is provided via the GNAT encodings instead.
This is likely what this DIE is about. */
encoding = (encoding == DW_ATE_signed_fixed
? DW_ATE_signed
: DW_ATE_unsigned);
}
/* With GNAT encodings, fixed-point information will be encoded in
the type name. Note that this can also occur with the above
zero-over-zero case, which is why this is a separate "if" rather
than an "else if". */
const char *gnat_encoding_suffix = nullptr;
if ((encoding == DW_ATE_signed || encoding == DW_ATE_unsigned)
&& cu->lang () == language_ada
&& name != nullptr)
{
gnat_encoding_suffix = gnat_encoded_fixed_point_type_info (name);
if (gnat_encoding_suffix != nullptr)
{
gdb_assert (startswith (gnat_encoding_suffix,
GNAT_FIXED_POINT_SUFFIX));
name = obstack_strndup (&cu->per_objfile->objfile->objfile_obstack,
name, gnat_encoding_suffix - name);
/* Use -1 here so that SUFFIX points at the "_" after the
"XF". */
gnat_encoding_suffix += strlen (GNAT_FIXED_POINT_SUFFIX) - 1;
encoding = (encoding == DW_ATE_signed
? DW_ATE_signed_fixed
: DW_ATE_unsigned_fixed);
}
}
type_allocator alloc (objfile, cu->lang ());
switch (encoding)
{
case DW_ATE_address:
/* Turn DW_ATE_address into a void * pointer. */
type = alloc.new_type (TYPE_CODE_VOID, TARGET_CHAR_BIT, NULL);
type = init_pointer_type (alloc, bits, name, type);
break;
case DW_ATE_boolean:
type = init_boolean_type (alloc, bits, 1, name);
break;
case DW_ATE_complex_float:
type = dwarf2_init_complex_target_type (cu, bits / 2, name,
byte_order);
if (type->code () == TYPE_CODE_ERROR)
{
if (name == nullptr)
{
struct obstack *obstack
= &cu->per_objfile->objfile->objfile_obstack;
name = obconcat (obstack, "_Complex ", type->name (),
nullptr);
}
type = alloc.new_type (TYPE_CODE_ERROR, bits, name);
}
else
type = init_complex_type (name, type);
break;
case DW_ATE_decimal_float:
type = init_decfloat_type (alloc, bits, name);
break;
case DW_ATE_float:
type = dwarf2_init_float_type (cu, bits, name, name, byte_order);
break;
case DW_ATE_signed:
type = dwarf2_init_integer_type (cu, bits, 0, name);
break;
case DW_ATE_unsigned:
if (cu->lang () == language_fortran
&& name
&& startswith (name, "character("))
type = init_character_type (alloc, bits, 1, name);
else
type = dwarf2_init_integer_type (cu, bits, 1, name);
break;
case DW_ATE_signed_char:
if (cu->lang () == language_ada
|| cu->lang () == language_m2
|| cu->lang () == language_pascal
|| cu->lang () == language_fortran)
type = init_character_type (alloc, bits, 0, name);
else
type = dwarf2_init_integer_type (cu, bits, 0, name);
break;
case DW_ATE_unsigned_char:
if (cu->lang () == language_ada
|| cu->lang () == language_m2
|| cu->lang () == language_pascal
|| cu->lang () == language_fortran
|| cu->lang () == language_rust)
type = init_character_type (alloc, bits, 1, name);
else
type = dwarf2_init_integer_type (cu, bits, 1, name);
break;
case DW_ATE_UTF:
{
type = init_character_type (alloc, bits, 1, name);
return set_die_type (die, type, cu);
}
break;
case DW_ATE_signed_fixed:
type = init_fixed_point_type (alloc, bits, 0, name);
finish_fixed_point_type (type, gnat_encoding_suffix, die, cu);
break;
case DW_ATE_unsigned_fixed:
type = init_fixed_point_type (alloc, bits, 1, name);
finish_fixed_point_type (type, gnat_encoding_suffix, die, cu);
break;
default:
complaint (_("unsupported DW_AT_encoding: '%s'"),
dwarf_type_encoding_name (encoding));
type = alloc.new_type (TYPE_CODE_ERROR, bits, name);
break;
}
if (type->code () == TYPE_CODE_INT
&& name != nullptr
&& strcmp (name, "char") == 0)
type->set_has_no_signedness (true);
maybe_set_alignment (cu, die, type);
type->set_endianity_is_not_default (not_default);
if (TYPE_SPECIFIC_FIELD (type) == TYPE_SPECIFIC_INT)
{
attr = dwarf2_attr (die, DW_AT_bit_size, cu);
if (attr != nullptr && attr->form_is_constant ())
{
unsigned real_bit_size = attr->constant_value (0);
if (real_bit_size >= 0 && real_bit_size <= 8 * type->length ())
{
attr = dwarf2_attr (die, DW_AT_data_bit_offset, cu);
/* Only use the attributes if they make sense together. */
if (attr == nullptr
|| (attr->form_is_constant ()
&& attr->constant_value (0) >= 0
&& (attr->constant_value (0) + real_bit_size
<= 8 * type->length ())))
{
TYPE_MAIN_TYPE (type)->type_specific.int_stuff.bit_size
= real_bit_size;
if (attr != nullptr)
TYPE_MAIN_TYPE (type)->type_specific.int_stuff.bit_offset
= attr->constant_value (0);
}
}
}
}
return set_die_type (die, type, cu);
}
/* A helper function that returns the name of DIE, if it refers to a
variable declaration. */
static const char *
var_decl_name (struct die_info *die, struct dwarf2_cu *cu)
{
if (die->tag != DW_TAG_variable)
return nullptr;
attribute *attr = dwarf2_attr (die, DW_AT_declaration, cu);
if (attr == nullptr || !attr->as_boolean ())
return nullptr;
attr = dwarf2_attr (die, DW_AT_name, cu);
if (attr == nullptr)
return nullptr;
return attr->as_string ();
}
/* Parse dwarf attribute if it's a block, reference or constant and put the
resulting value of the attribute into struct bound_prop.
Returns 1 if ATTR could be resolved into PROP, 0 otherwise. */
static int
attr_to_dynamic_prop (const struct attribute *attr, struct die_info *die,
struct dwarf2_cu *cu, struct dynamic_prop *prop,
struct type *default_type)
{
struct dwarf2_property_baton *baton;
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct obstack *obstack = &objfile->objfile_obstack;
gdb_assert (default_type != NULL);
if (attr == NULL || prop == NULL)
return 0;
if (attr->form_is_block ())
{
baton = XOBNEW (obstack, struct dwarf2_property_baton);
baton->property_type = default_type;
baton->locexpr.per_cu = cu->per_cu;
baton->locexpr.per_objfile = per_objfile;
struct dwarf_block block;
if (attr->form == DW_FORM_data16)
{
size_t data_size = 16;
block.size = (data_size
+ 2 /* Extra bytes for DW_OP and arg. */);
gdb_byte *data = XOBNEWVEC (obstack, gdb_byte, block.size);
data[0] = DW_OP_implicit_value;
data[1] = data_size;
memcpy (&data[2], attr->as_block ()->data, data_size);
block.data = data;
}
else
block = *attr->as_block ();
baton->locexpr.size = block.size;
baton->locexpr.data = block.data;
switch (attr->name)
{
case DW_AT_string_length:
baton->locexpr.is_reference = true;
break;
default:
baton->locexpr.is_reference = false;
break;
}
prop->set_locexpr (baton);
gdb_assert (prop->baton () != NULL);
}
else if (attr->form_is_ref ())
{
struct dwarf2_cu *target_cu = cu;
struct die_info *target_die;
struct attribute *target_attr;
target_die = follow_die_ref (die, attr, &target_cu);
target_attr = dwarf2_attr (target_die, DW_AT_location, target_cu);
if (target_attr == NULL)
target_attr = dwarf2_attr (target_die, DW_AT_data_member_location,
target_cu);
if (target_attr == nullptr)
target_attr = dwarf2_attr (target_die, DW_AT_data_bit_offset,
target_cu);
if (target_attr == NULL)
{
const char *name = var_decl_name (target_die, target_cu);
if (name != nullptr)
{
prop->set_variable_name (name);
return 1;
}
return 0;
}
switch (target_attr->name)
{
case DW_AT_location:
if (target_attr->form_is_section_offset ())
{
baton = XOBNEW (obstack, struct dwarf2_property_baton);
baton->property_type = die_type (target_die, target_cu);
fill_in_loclist_baton (cu, &baton->loclist, target_attr);
prop->set_loclist (baton);
gdb_assert (prop->baton () != NULL);
}
else if (target_attr->form_is_block ())
{
baton = XOBNEW (obstack, struct dwarf2_property_baton);
baton->property_type = die_type (target_die, target_cu);
baton->locexpr.per_cu = cu->per_cu;
baton->locexpr.per_objfile = per_objfile;
struct dwarf_block *block = target_attr->as_block ();
baton->locexpr.size = block->size;
baton->locexpr.data = block->data;
baton->locexpr.is_reference = true;
prop->set_locexpr (baton);
gdb_assert (prop->baton () != NULL);
}
else
{
dwarf2_invalid_attrib_class_complaint ("DW_AT_location",
"dynamic property");
return 0;
}
break;
case DW_AT_data_member_location:
case DW_AT_data_bit_offset:
{
LONGEST offset;
if (!handle_member_location (target_die, target_cu, &offset))
return 0;
baton = XOBNEW (obstack, struct dwarf2_property_baton);
baton->property_type = read_type_die (target_die->parent,
target_cu);
baton->offset_info.offset = offset;
baton->offset_info.type = die_type (target_die, target_cu);
prop->set_addr_offset (baton);
break;
}
}
}
else if (attr->form_is_constant ())
prop->set_const_val (attr->constant_value (0));
else if (attr->form_is_section_offset ())
{
switch (attr->name)
{
case DW_AT_string_length:
baton = XOBNEW (obstack, struct dwarf2_property_baton);
baton->property_type = default_type;
fill_in_loclist_baton (cu, &baton->loclist, attr);
prop->set_loclist (baton);
gdb_assert (prop->baton () != NULL);
break;
default:
goto invalid;
}
}
else
goto invalid;
return 1;
invalid:
dwarf2_invalid_attrib_class_complaint (dwarf_form_name (attr->form),
dwarf2_name (die, cu));
return 0;
}
/* See read.h. */
/* Read the DW_AT_type attribute for a sub-range. If this attribute is not
present (which is valid) then compute the default type based on the
compilation units address size. */
static struct type *
read_subrange_index_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *index_type = die_type (die, cu);
/* Dwarf-2 specifications explicitly allows to create subrange types
without specifying a base type.
In that case, the base type must be set to the type of
the lower bound, upper bound or count, in that order, if any of these
three attributes references an object that has a type.
If no base type is found, the Dwarf-2 specifications say that
a signed integer type of size equal to the size of an address should
be used.
For the following C code: `extern char gdb_int [];'
GCC produces an empty range DIE.
FIXME: muller/2010-05-28: Possible references to object for low bound,
high bound or count are not yet handled by this code. */
if (index_type->code () == TYPE_CODE_VOID)
index_type = cu->addr_sized_int_type (false);
return index_type;
}
/* Read the given DW_AT_subrange DIE. */
static struct type *
read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *base_type, *orig_base_type;
struct type *range_type;
struct attribute *attr;
struct dynamic_prop low, high;
int low_default_is_valid;
int high_bound_is_count = 0;
const char *name;
orig_base_type = read_subrange_index_type (die, cu);
/* If ORIG_BASE_TYPE is a typedef, it will not be TYPE_UNSIGNED,
whereas the real type might be. So, we use ORIG_BASE_TYPE when
creating the range type, but we use the result of check_typedef
when examining properties of the type. */
base_type = check_typedef (orig_base_type);
/* The die_type call above may have already set the type for this DIE. */
range_type = get_die_type (die, cu);
if (range_type)
return range_type;
high.set_const_val (0);
/* Set LOW_DEFAULT_IS_VALID if current language and DWARF version allow
omitting DW_AT_lower_bound. */
switch (cu->lang ())
{
case language_c:
case language_cplus:
low.set_const_val (0);
low_default_is_valid = 1;
break;
case language_fortran:
low.set_const_val (1);
low_default_is_valid = 1;
break;
case language_d:
case language_objc:
case language_rust:
low.set_const_val (0);
low_default_is_valid = (cu->header.version >= 4);
break;
case language_ada:
case language_m2:
case language_pascal:
low.set_const_val (1);
low_default_is_valid = (cu->header.version >= 4);
break;
default:
low.set_const_val (0);
low_default_is_valid = 0;
break;
}
attr = dwarf2_attr (die, DW_AT_lower_bound, cu);
if (attr != nullptr)
attr_to_dynamic_prop (attr, die, cu, &low, base_type);
else if (!low_default_is_valid)
complaint (_("Missing DW_AT_lower_bound "
"- DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
struct attribute *attr_ub, *attr_count;
attr = attr_ub = dwarf2_attr (die, DW_AT_upper_bound, cu);
if (!attr_to_dynamic_prop (attr, die, cu, &high, base_type))
{
attr = attr_count = dwarf2_attr (die, DW_AT_count, cu);
if (attr_to_dynamic_prop (attr, die, cu, &high, base_type))
{
/* If bounds are constant do the final calculation here. */
if (low.is_constant () && high.is_constant ())
high.set_const_val (low.const_val () + high.const_val () - 1);
else
high_bound_is_count = 1;
}
else
{
if (attr_ub != NULL)
complaint (_("Unresolved DW_AT_upper_bound "
"- DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
if (attr_count != NULL)
complaint (_("Unresolved DW_AT_count "
"- DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
}
}
LONGEST bias = 0;
struct attribute *bias_attr = dwarf2_attr (die, DW_AT_GNU_bias, cu);
if (bias_attr != nullptr && bias_attr->form_is_constant ())
bias = bias_attr->constant_value (0);
/* Normally, the DWARF producers are expected to use a signed
constant form (Eg. DW_FORM_sdata) to express negative bounds.
But this is unfortunately not always the case, as witnessed
with GCC, for instance, where the ambiguous DW_FORM_dataN form
is used instead. To work around that ambiguity, we treat
the bounds as signed, and thus sign-extend their values, when
the base type is signed.
Skip it if the base type's length is larger than ULONGEST, to avoid
the undefined behavior of a too large left shift. We don't really handle
constants larger than 8 bytes anyway, at the moment. */
if (base_type->length () <= sizeof (ULONGEST))
{
ULONGEST negative_mask
= -((ULONGEST) 1 << (base_type->length () * TARGET_CHAR_BIT - 1));
if (low.is_constant ()
&& !base_type->is_unsigned () && (low.const_val () & negative_mask))
low.set_const_val (low.const_val () | negative_mask);
if (high.is_constant ()
&& !base_type->is_unsigned () && (high.const_val () & negative_mask))
high.set_const_val (high.const_val () | negative_mask);
}
/* Check for bit and byte strides. */
struct dynamic_prop byte_stride_prop;
attribute *attr_byte_stride = dwarf2_attr (die, DW_AT_byte_stride, cu);
if (attr_byte_stride != nullptr)
{
struct type *prop_type = cu->addr_sized_int_type (false);
attr_to_dynamic_prop (attr_byte_stride, die, cu, &byte_stride_prop,
prop_type);
}
struct dynamic_prop bit_stride_prop;
attribute *attr_bit_stride = dwarf2_attr (die, DW_AT_bit_stride, cu);
if (attr_bit_stride != nullptr)
{
/* It only makes sense to have either a bit or byte stride. */
if (attr_byte_stride != nullptr)
{
complaint (_("Found DW_AT_bit_stride and DW_AT_byte_stride "
"- DIE at %s [in module %s]"),
sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
attr_bit_stride = nullptr;
}
else
{
struct type *prop_type = cu->addr_sized_int_type (false);
attr_to_dynamic_prop (attr_bit_stride, die, cu, &bit_stride_prop,
prop_type);
}
}
type_allocator alloc (cu->per_objfile->objfile, cu->lang ());
if (attr_byte_stride != nullptr
|| attr_bit_stride != nullptr)
{
bool byte_stride_p = (attr_byte_stride != nullptr);
struct dynamic_prop *stride
= byte_stride_p ? &byte_stride_prop : &bit_stride_prop;
range_type
= create_range_type_with_stride (alloc, orig_base_type, &low,
&high, bias, stride, byte_stride_p);
}
else
range_type = create_range_type (alloc, orig_base_type, &low, &high, bias);
if (high_bound_is_count)
range_type->bounds ()->flag_upper_bound_is_count = 1;
/* Ada expects an empty array on no boundary attributes. */
if (attr == NULL && cu->lang () != language_ada)
range_type->bounds ()->high.set_undefined ();
name = dwarf2_full_name (nullptr, die, cu);
if (name)
range_type->set_name (name);
attr = dwarf2_attr (die, DW_AT_byte_size, cu);
if (attr != nullptr)
range_type->set_length (attr->constant_value (0));
maybe_set_alignment (cu, die, range_type);
set_die_type (die, range_type, cu);
/* set_die_type should be already done. */
set_descriptive_type (range_type, die, cu);
return range_type;
}
static struct type *
read_unspecified_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *type;
type = (type_allocator (cu->per_objfile->objfile, cu->lang ())
.new_type (TYPE_CODE_VOID, 0, nullptr));
type->set_name (dwarf2_name (die, cu));
/* In Ada, an unspecified type is typically used when the description
of the type is deferred to a different unit. When encountering
such a type, we treat it as a stub, and try to resolve it later on,
when needed.
Mark this as a stub type for all languages though. */
type->set_is_stub (true);
return set_die_type (die, type, cu);
}
/* Read a single die and all its descendents. Set the die's sibling
field to NULL; set other fields in the die correctly, and set all
of the descendents' fields correctly. PARENT is the parent of the
die in question. */
die_info *
cutu_reader::read_die_and_children (die_info *parent)
{
die_info *die = this->read_full_die (0, true);
if (die == nullptr)
return nullptr;
bool inserted = m_cu->die_hash.emplace (die).second;
gdb_assert (inserted);
if (die->has_children)
die->child = this->read_die_and_siblings (die);
else
die->child = nullptr;
die->sibling = nullptr;
die->parent = parent;
return die;
}
/* Read a die, all of its descendents, and all of its siblings; set
all of the fields of all of the dies correctly. Arguments are as
in read_die_and_children. */
die_info *
cutu_reader::read_die_and_siblings (die_info *parent)
{
die_info *first_die = nullptr;
die_info *last_sibling = nullptr;
while (true)
{
die_info *die = this->read_die_and_children (parent);
if (die == nullptr)
return first_die;
if (first_die == nullptr)
first_die = die;
else
last_sibling->sibling = die;
last_sibling = die;
}
}
/* See read.h. */
void
cutu_reader::read_all_dies ()
{
const gdb_byte *begin_info_ptr = m_info_ptr;
if (m_top_level_die->has_children)
{
gdb_assert (m_cu->die_hash.empty ());
m_cu->die_hash.reserve (m_cu->header.get_length_without_initial () / 12);
m_top_level_die->child = this->read_die_and_siblings (m_top_level_die);
}
m_cu->dies = m_top_level_die;
if (dwarf_die_debug)
{
gdb_printf (gdb_stdlog, "Read die from %s@0x%tx of %s:\n",
m_die_section->get_name (),
begin_info_ptr - m_die_section->buffer,
bfd_get_filename (m_abfd));
m_top_level_die->child->dump (dwarf_die_debug);
}
}
/* Read a die and all its attributes, leave space for NUM_EXTRA_ATTRS
attributes.
The caller is responsible for filling in the extra attributes
and updating die_info::num_attrs.
Return a newly allocated die with its information, except for its
child, sibling, and parent fields. */
die_info *
cutu_reader::read_full_die (int num_extra_attrs, bool allow_reprocess)
{
unsigned int bytes_read, i;
const struct abbrev_info *abbrev;
sect_offset sect_off = static_cast<sect_offset> (m_info_ptr - m_buffer);
unsigned int abbrev_number
= read_unsigned_leb128 (m_abfd, m_info_ptr, &bytes_read);
m_info_ptr += bytes_read;
if (abbrev_number == 0)
return nullptr;
abbrev = m_abbrev_table->lookup_abbrev (abbrev_number);
if (!abbrev)
error (_(DWARF_ERROR_PREFIX
"could not find abbrev number %d [in module %s]"),
abbrev_number, bfd_get_filename (m_abfd));
die_info *die = die_info::allocate (&m_cu->comp_unit_obstack,
abbrev->num_attrs + num_extra_attrs);
die->sect_off = sect_off;
die->tag = abbrev->tag;
die->abbrev = abbrev_number;
die->has_children = abbrev->has_children;
/* Make the result usable.
The caller needs to update num_attrs after adding the extra
attributes. */
die->num_attrs = abbrev->num_attrs;
for (i = 0; i < abbrev->num_attrs; ++i)
m_info_ptr = this->read_attribute (&die->attrs[i], &abbrev->attrs[i],
m_info_ptr, allow_reprocess);
return die;
}
/* Read a die and all its attributes.
Return a newly allocated die with its information, except for its
child, sibling, and parent fields. */
die_info *
cutu_reader::read_toplevel_die (gdb::array_view<attribute *> extra_attrs)
{
const gdb_byte *begin_info_ptr = m_info_ptr;
die_info *die = this->read_full_die (extra_attrs.size (), false);
/* Copy in the extra attributes, if any. */
attribute *next = &die->attrs[die->num_attrs];
for (attribute *extra : extra_attrs)
*next++ = *extra;
struct attribute *attr = die->attr (DW_AT_str_offsets_base);
if (attr != nullptr && attr->form_is_unsigned ())
m_cu->str_offsets_base = attr->as_unsigned ();
attr = die->attr (DW_AT_loclists_base);
if (attr != nullptr)
m_cu->loclist_base = attr->as_unsigned ();
auto maybe_addr_base = die->addr_base ();
if (maybe_addr_base.has_value ())
m_cu->addr_base = *maybe_addr_base;
attr = die->attr (DW_AT_rnglists_base);
if (attr != nullptr)
m_cu->rnglists_base = attr->as_unsigned ();
for (int i = 0; i < die->num_attrs; ++i)
{
if (die->attrs[i].form_requires_reprocessing ())
this->read_attribute_reprocess (&die->attrs[i], die->tag);
}
die->num_attrs += extra_attrs.size ();
if (dwarf_die_debug)
{
gdb_printf (gdb_stdlog, "Read die from %s@0x%tx of %s:\n",
m_die_section->get_name (),
(begin_info_ptr - m_die_section->buffer),
bfd_get_filename (m_abfd));
die->dump (dwarf_die_debug);
}
return die;
}
struct compunit_symtab *
cooked_index_functions::find_compunit_symtab_by_address
(struct objfile *objfile, CORE_ADDR address)
{
if (objfile->sect_index_data == -1)
return nullptr;
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
cooked_index *table = wait (objfile, true);
CORE_ADDR baseaddr = objfile->data_section_offset ();
dwarf2_per_cu *per_cu
= table->lookup ((unrelocated_addr) (address - baseaddr));
if (per_cu == nullptr)
return nullptr;
return dw2_instantiate_symtab (per_cu, per_objfile, false);
}
bool
cooked_index_functions::expand_symtabs_matching
(objfile *objfile,
expand_symtabs_file_matcher file_matcher,
const lookup_name_info *lookup_name,
expand_symtabs_symbol_matcher symbol_matcher,
expand_symtabs_expansion_listener expansion_notify,
block_search_flags search_flags,
domain_search_flags domain,
expand_symtabs_lang_matcher lang_matcher)
{
dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
cooked_index *table = wait (objfile, true);
dw_expand_symtabs_matching_file_matcher (per_objfile, file_matcher);
/* This invariant is documented in quick-functions.h. */
gdb_assert (lookup_name != nullptr || symbol_matcher == nullptr);
if (lookup_name == nullptr)
{
for (dwarf2_per_cu *per_cu : all_units_range (per_objfile->per_bfd))
{
QUIT;
if (!dw2_expand_symtabs_matching_one (per_cu, per_objfile,
file_matcher,
expansion_notify,
lang_matcher))
return false;
}
return true;
}
lookup_name_info lookup_name_without_params
= lookup_name->make_ignore_params ();
bool completing = lookup_name->completion_mode ();
/* Unique styles of language splitting. */
static const enum language unique_styles[] =
{
/* No splitting is also a style. */
language_c,
/* This includes Rust. */
language_cplus,
/* This includes Go. */
language_d,
language_ada
};
symbol_name_match_type match_type
= lookup_name_without_params.match_type ();
std::bitset<nr_languages> unique_styles_used;
if (lang_matcher != nullptr)
for (unsigned iter = 0; iter < nr_languages; ++iter)
{
enum language lang = (enum language) iter;
if (!lang_matcher (lang))
continue;
switch (lang)
{
case language_cplus:
case language_rust:
unique_styles_used[language_cplus] = true;
break;
case language_d:
case language_go:
unique_styles_used[language_d] = true;
break;
case language_ada:
unique_styles_used[language_ada] = true;
break;
default:
unique_styles_used[language_c] = true;
}
if (unique_styles_used.count ()
== sizeof (unique_styles) / sizeof (unique_styles[0]))
break;
}
for (enum language lang : unique_styles)
{
if (lang_matcher != nullptr
&& !unique_styles_used.test (lang))
continue;
std::vector<std::string_view> name_vec
= lookup_name_without_params.split_name (lang);
std::vector<std::string> name_str_vec (name_vec.begin (), name_vec.end ());
std::vector<lookup_name_info> segment_lookup_names;
segment_lookup_names.reserve (name_vec.size ());
for (auto &segment_name : name_str_vec)
segment_lookup_names.emplace_back (segment_name, match_type,
completing, true);
for (const cooked_index_entry *entry : table->find (name_str_vec.back (),
completing))
{
QUIT;
/* No need to consider symbols from expanded CUs. */
if (per_objfile->symtab_set_p (entry->per_cu))
continue;
/* If file-matching was done, we don't need to consider
symbols from unmarked CUs. */
if (file_matcher != nullptr && !entry->per_cu->mark)
continue;
/* See if the symbol matches the type filter. */
if (!entry->matches (search_flags)
|| !entry->matches (domain))
continue;
if (lang_matcher != nullptr)
{
/* Try to skip CUs with non-matching language. */
entry->per_cu->ensure_lang (per_objfile);
if (!entry->per_cu->maybe_multi_language ()
&& !lang_matcher (entry->per_cu->lang ()))
continue;
}
/* We've found the base name of the symbol; now walk its
parentage chain, ensuring that each component
matches. */
bool found = true;
const cooked_index_entry *parent = entry->get_parent ();
const language_defn *lang_def = language_def (entry->lang);
for (int i = name_vec.size () - 1; i > 0; --i)
{
/* If we ran out of entries, or if this segment doesn't
match, this did not match. */
if (parent == nullptr)
{
found = false;
break;
}
if (parent->lang != language_unknown)
{
symbol_name_matcher_ftype *name_matcher
= lang_def->get_symbol_name_matcher
(segment_lookup_names[i-1]);
if (!name_matcher (parent->canonical,
segment_lookup_names[i-1], nullptr))
{
found = false;
break;
}
}
parent = parent->get_parent ();
}
if (!found)
continue;
/* Might have been looking for "a::b" and found
"x::a::b". */
if (((match_type == symbol_name_match_type::FULL
|| (lang != language_ada
&& match_type == symbol_name_match_type::EXPRESSION)))
&& parent != nullptr)
continue;
/* Check that the full name matches -- either by matching
the lookup name ourselves, or by passing the full name to
the symbol matcher. The former is a bit of a hack: it
seems like the loop above could just examine every
element of the name, avoiding the need to check here; but
this is hard. See PR symtab/32733. */
if (symbol_matcher != nullptr || entry->lang != language_unknown)
{
auto_obstack temp_storage;
const char *full_name = entry->full_name (&temp_storage,
FOR_ADA_LINKAGE_NAME);
if (symbol_matcher == nullptr)
{
symbol_name_matcher_ftype *name_matcher
= (lang_def->get_symbol_name_matcher
(lookup_name_without_params));
if (!name_matcher (full_name, lookup_name_without_params,
nullptr))
continue;
}
else if (!symbol_matcher (full_name))
continue;
}
if (!dw2_expand_symtabs_matching_one (entry->per_cu, per_objfile,
file_matcher,
expansion_notify, nullptr))
return false;
}
}
return true;
}
/* Start reading .debug_info using the indexer. */
static void
start_debug_info_reader (dwarf2_per_objfile *per_objfile)
{
/* Set the index table early so that sharing works even while
scanning; and then start the scanning. */
dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
auto worker = std::make_unique<cooked_index_worker_debug_info> (per_objfile);
per_bfd->start_reading (std::make_unique<cooked_index> (std::move (worker)));
}
/* Read the .debug_loclists or .debug_rnglists header (they are the same format)
contents from the given SECTION in the HEADER.
HEADER_OFFSET is the offset of the header in the section. */
static void
read_loclists_rnglists_header (struct loclists_rnglists_header *header,
struct dwarf2_section_info *section,
sect_offset header_offset)
{
unsigned int bytes_read;
bfd *abfd = section->get_bfd_owner ();
const gdb_byte *info_ptr = section->buffer + to_underlying (header_offset);
header->length = read_initial_length (abfd, info_ptr, &bytes_read);
info_ptr += bytes_read;
header->version = read_2_bytes (abfd, info_ptr);
info_ptr += 2;
header->addr_size = read_1_byte (abfd, info_ptr);
info_ptr += 1;
header->segment_collector_size = read_1_byte (abfd, info_ptr);
info_ptr += 1;
header->offset_entry_count = read_4_bytes (abfd, info_ptr);
}
/* Return the DW_AT_loclists_base value for the CU. */
static ULONGEST
lookup_loclist_base (struct dwarf2_cu *cu)
{
/* For the .dwo unit, the loclist_base points to the first offset following
the header. The header consists of the following entities-
1. Unit Length (4 bytes for 32 bit DWARF format, and 12 bytes for the 64
bit format)
2. version (2 bytes)
3. address size (1 byte)
4. segment selector size (1 byte)
5. offset entry count (4 bytes)
These sizes are derived as per the DWARFv5 standard. */
if (cu->dwo_unit != nullptr)
{
if (cu->header.initial_length_size == 4)
return LOCLIST_HEADER_SIZE32;
return LOCLIST_HEADER_SIZE64;
}
return cu->loclist_base;
}
/* Given a DW_FORM_loclistx value LOCLIST_INDEX, fetch the offset from the
array of offsets in the .debug_loclists section. */
static sect_offset
read_loclist_index (struct dwarf2_cu *cu, ULONGEST loclist_index)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
bfd *abfd = objfile->obfd.get ();
ULONGEST loclist_header_size =
(cu->header.initial_length_size == 4 ? LOCLIST_HEADER_SIZE32
: LOCLIST_HEADER_SIZE64);
ULONGEST loclist_base = lookup_loclist_base (cu);
/* Offset in .debug_loclists of the offset for LOCLIST_INDEX. */
ULONGEST start_offset =
loclist_base + loclist_index * cu->header.offset_size;
/* Get loclists section. */
struct dwarf2_section_info *section = cu_debug_loc_section (cu);
/* Read the loclists section content. */
section->read (objfile);
if (section->buffer == NULL)
error (_("DW_FORM_loclistx used without .debug_loclists "
"section [in module %s]"), objfile_name (objfile));
/* DW_AT_loclists_base points after the .debug_loclists contribution header,
so if loclist_base is smaller than the header size, we have a problem. */
if (loclist_base < loclist_header_size)
error (_("DW_AT_loclists_base is smaller than header size [in module %s]"),
objfile_name (objfile));
/* Read the header of the loclists contribution. */
struct loclists_rnglists_header header;
read_loclists_rnglists_header (&header, section,
(sect_offset) (loclist_base - loclist_header_size));
/* Verify the loclist index is valid. */
if (loclist_index >= header.offset_entry_count)
error (_("DW_FORM_loclistx pointing outside of "
".debug_loclists offset array [in module %s]"),
objfile_name (objfile));
/* Validate that reading won't go beyond the end of the section. */
if (start_offset + cu->header.offset_size > section->size)
error (_("Reading DW_FORM_loclistx index beyond end of"
".debug_loclists section [in module %s]"),
objfile_name (objfile));
const gdb_byte *info_ptr = section->buffer + start_offset;
if (cu->header.offset_size == 4)
return (sect_offset) (bfd_get_32 (abfd, info_ptr) + loclist_base);
else
return (sect_offset) (bfd_get_64 (abfd, info_ptr) + loclist_base);
}
/* Given a DW_FORM_rnglistx value RNGLIST_INDEX, fetch the offset from the
array of offsets in the .debug_rnglists section. */
static sect_offset
read_rnglist_index (struct dwarf2_cu *cu, ULONGEST rnglist_index,
dwarf_tag tag)
{
struct dwarf2_per_objfile *dwarf2_per_objfile = cu->per_objfile;
struct objfile *objfile = dwarf2_per_objfile->objfile;
bfd *abfd = objfile->obfd.get ();
ULONGEST rnglist_header_size =
(cu->header.initial_length_size == 4 ? RNGLIST_HEADER_SIZE32
: RNGLIST_HEADER_SIZE64);
/* When reading a DW_FORM_rnglistx from a DWO, we read from the DWO's
.debug_rnglists.dwo section. The rnglists base given in the skeleton
doesn't apply. */
ULONGEST rnglist_base =
(cu->dwo_unit != nullptr) ? rnglist_header_size : cu->rnglists_base;
/* Offset in .debug_rnglists of the offset for RNGLIST_INDEX. */
ULONGEST start_offset =
rnglist_base + rnglist_index * cu->header.offset_size;
/* Get rnglists section. */
struct dwarf2_section_info *section = cu_debug_rnglists_section (cu, tag);
/* Read the rnglists section content. */
section->read (objfile);
if (section->buffer == nullptr)
error (_("DW_FORM_rnglistx used without .debug_rnglists section "
"[in module %s]"),
objfile_name (objfile));
/* DW_AT_rnglists_base points after the .debug_rnglists contribution header,
so if rnglist_base is smaller than the header size, we have a problem. */
if (rnglist_base < rnglist_header_size)
error (_("DW_AT_rnglists_base is smaller than header size [in module %s]"),
objfile_name (objfile));
/* Read the header of the rnglists contribution. */
struct loclists_rnglists_header header;
read_loclists_rnglists_header (&header, section,
(sect_offset) (rnglist_base - rnglist_header_size));
/* Verify the rnglist index is valid. */
if (rnglist_index >= header.offset_entry_count)
error (_("DW_FORM_rnglistx index pointing outside of "
".debug_rnglists offset array [in module %s]"),
objfile_name (objfile));
/* Validate that reading won't go beyond the end of the section. */
if (start_offset + cu->header.offset_size > section->size)
error (_("Reading DW_FORM_rnglistx index beyond end of"
".debug_rnglists section [in module %s]"),
objfile_name (objfile));
const gdb_byte *info_ptr = section->buffer + start_offset;
if (cu->header.offset_size == 4)
return (sect_offset) (read_4_bytes (abfd, info_ptr) + rnglist_base);
else
return (sect_offset) (read_8_bytes (abfd, info_ptr) + rnglist_base);
}
/* Process the attributes that had to be skipped in the first round. These
attributes are the ones that need str_offsets_base or addr_base attributes.
They could not have been processed in the first round, because at the time
the values of str_offsets_base or addr_base may not have been known. */
void
cutu_reader::read_attribute_reprocess (attribute *attr, dwarf_tag tag)
{
switch (attr->form)
{
case DW_FORM_addrx:
case DW_FORM_GNU_addr_index:
attr->set_address (read_addr_index (m_cu,
attr->as_unsigned_reprocess ()));
break;
case DW_FORM_loclistx:
{
sect_offset loclists_sect_off
= read_loclist_index (m_cu, attr->as_unsigned_reprocess ());
attr->set_unsigned (to_underlying (loclists_sect_off));
}
break;
case DW_FORM_rnglistx:
{
sect_offset rnglists_sect_off
= read_rnglist_index (m_cu, attr->as_unsigned_reprocess (), tag);
attr->set_unsigned (to_underlying (rnglists_sect_off));
}
break;
case DW_FORM_strx:
case DW_FORM_strx1:
case DW_FORM_strx2:
case DW_FORM_strx3:
case DW_FORM_strx4:
case DW_FORM_GNU_str_index:
{
unsigned int str_index = attr->as_unsigned_reprocess ();
gdb_assert (!attr->canonical_string_p ());
if (m_dwo_file != NULL)
attr->set_string_noncanonical
(this->read_dwo_str_index (str_index));
else
attr->set_string_noncanonical (read_stub_str_index (m_cu,
str_index));
break;
}
default:
gdb_assert_not_reached ("Unexpected DWARF form.");
}
}
/* Read an attribute value described by an attribute form. */
const gdb_byte *
cutu_reader::read_attribute_value (attribute *attr, unsigned form,
LONGEST implicit_const,
const gdb_byte *info_ptr,
bool allow_reprocess)
{
dwarf2_per_objfile *per_objfile = m_cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct comp_unit_head *cu_header = &m_cu->header;
unsigned int bytes_read;
struct dwarf_block *blk;
attr->form = (enum dwarf_form) form;
switch (form)
{
case DW_FORM_ref_addr:
if (cu_header->version == 2)
attr->set_unsigned ((ULONGEST) cu_header->read_address (m_abfd,
info_ptr,
&bytes_read));
else
attr->set_unsigned (cu_header->read_offset (m_abfd, info_ptr,
&bytes_read));
info_ptr += bytes_read;
break;
case DW_FORM_GNU_ref_alt:
attr->set_unsigned (cu_header->read_offset (m_abfd, info_ptr,
&bytes_read));
info_ptr += bytes_read;
break;
case DW_FORM_addr:
{
unrelocated_addr addr
= cu_header->read_address (m_abfd, info_ptr, &bytes_read);
attr->set_address (addr);
info_ptr += bytes_read;
}
break;
case DW_FORM_block2:
blk = dwarf_alloc_block (m_cu);
blk->size = read_2_bytes (m_abfd, info_ptr);
info_ptr += 2;
blk->data = read_n_bytes (m_abfd, info_ptr, blk->size);
info_ptr += blk->size;
attr->set_block (blk);
break;
case DW_FORM_block4:
blk = dwarf_alloc_block (m_cu);
blk->size = read_4_bytes (m_abfd, info_ptr);
info_ptr += 4;
blk->data = read_n_bytes (m_abfd, info_ptr, blk->size);
info_ptr += blk->size;
attr->set_block (blk);
break;
case DW_FORM_data2:
attr->set_unsigned (read_2_bytes (m_abfd, info_ptr));
info_ptr += 2;
break;
case DW_FORM_data4:
attr->set_unsigned (read_4_bytes (m_abfd, info_ptr));
info_ptr += 4;
break;
case DW_FORM_data8:
attr->set_unsigned (read_8_bytes (m_abfd, info_ptr));
info_ptr += 8;
break;
case DW_FORM_data16:
blk = dwarf_alloc_block (m_cu);
blk->size = 16;
blk->data = read_n_bytes (m_abfd, info_ptr, 16);
info_ptr += 16;
attr->set_block (blk);
break;
case DW_FORM_sec_offset:
attr->set_unsigned (cu_header->read_offset (m_abfd, info_ptr,
&bytes_read));
info_ptr += bytes_read;
break;
case DW_FORM_loclistx:
{
attr->set_unsigned_reprocess (read_unsigned_leb128 (m_abfd, info_ptr,
&bytes_read));
info_ptr += bytes_read;
if (allow_reprocess)
this->read_attribute_reprocess (attr);
}
break;
case DW_FORM_string:
attr->set_string_noncanonical (read_direct_string (m_abfd, info_ptr,
&bytes_read));
info_ptr += bytes_read;
break;
case DW_FORM_strp:
if (!m_cu->per_cu->is_dwz)
{
attr->set_string_noncanonical (read_indirect_string (per_objfile,
m_abfd, info_ptr,
cu_header,
&bytes_read));
info_ptr += bytes_read;
break;
}
[[fallthrough]];
case DW_FORM_line_strp:
if (!m_cu->per_cu->is_dwz)
{
attr->set_string_noncanonical
(per_objfile->read_line_string (info_ptr, cu_header,
&bytes_read));
info_ptr += bytes_read;
break;
}
[[fallthrough]];
case DW_FORM_GNU_strp_alt:
{
dwz_file *dwz = per_objfile->per_bfd->get_dwz_file (true);
LONGEST str_offset
= cu_header->read_offset (m_abfd, info_ptr, &bytes_read);
attr->set_string_noncanonical
(dwz->read_string (objfile, str_offset));
info_ptr += bytes_read;
}
break;
case DW_FORM_exprloc:
case DW_FORM_block:
blk = dwarf_alloc_block (m_cu);
blk->size = read_unsigned_leb128 (m_abfd, info_ptr, &bytes_read);
info_ptr += bytes_read;
blk->data = read_n_bytes (m_abfd, info_ptr, blk->size);
info_ptr += blk->size;
attr->set_block (blk);
break;
case DW_FORM_block1:
blk = dwarf_alloc_block (m_cu);
blk->size = read_1_byte (m_abfd, info_ptr);
info_ptr += 1;
blk->data = read_n_bytes (m_abfd, info_ptr, blk->size);
info_ptr += blk->size;
attr->set_block (blk);
break;
case DW_FORM_data1:
case DW_FORM_flag:
attr->set_unsigned (read_1_byte (m_abfd, info_ptr));
info_ptr += 1;
break;
case DW_FORM_flag_present:
attr->set_unsigned (1);
break;
case DW_FORM_sdata:
attr->set_signed (read_signed_leb128 (m_abfd, info_ptr, &bytes_read));
info_ptr += bytes_read;
break;
case DW_FORM_rnglistx:
{
attr->set_unsigned_reprocess (read_unsigned_leb128 (m_abfd, info_ptr,
&bytes_read));
info_ptr += bytes_read;
if (allow_reprocess)
this->read_attribute_reprocess (attr);
}
break;
case DW_FORM_udata:
attr->set_unsigned (read_unsigned_leb128 (m_abfd, info_ptr, &bytes_read));
info_ptr += bytes_read;
break;
case DW_FORM_ref1:
attr->set_unsigned ((to_underlying (cu_header->sect_off)
+ read_1_byte (m_abfd, info_ptr)));
info_ptr += 1;
break;
case DW_FORM_ref2:
attr->set_unsigned ((to_underlying (cu_header->sect_off)
+ read_2_bytes (m_abfd, info_ptr)));
info_ptr += 2;
break;
case DW_FORM_ref4:
attr->set_unsigned ((to_underlying (cu_header->sect_off)
+ read_4_bytes (m_abfd, info_ptr)));
info_ptr += 4;
break;
case DW_FORM_ref8:
attr->set_unsigned ((to_underlying (cu_header->sect_off)
+ read_8_bytes (m_abfd, info_ptr)));
info_ptr += 8;
break;
case DW_FORM_ref_sig8:
attr->set_signature (read_8_bytes (m_abfd, info_ptr));
info_ptr += 8;
break;
case DW_FORM_ref_udata:
attr->set_unsigned ((to_underlying (cu_header->sect_off)
+ read_unsigned_leb128 (m_abfd, info_ptr,
&bytes_read)));
info_ptr += bytes_read;
break;
case DW_FORM_indirect:
form = read_unsigned_leb128 (m_abfd, info_ptr, &bytes_read);
info_ptr += bytes_read;
if (form == DW_FORM_implicit_const)
{
implicit_const = read_signed_leb128 (m_abfd, info_ptr, &bytes_read);
info_ptr += bytes_read;
}
info_ptr = this->read_attribute_value (attr, form, implicit_const,
info_ptr, allow_reprocess);
break;
case DW_FORM_implicit_const:
attr->set_signed (implicit_const);
break;
case DW_FORM_addrx:
case DW_FORM_GNU_addr_index:
attr->set_unsigned_reprocess (read_unsigned_leb128 (m_abfd, info_ptr,
&bytes_read));
info_ptr += bytes_read;
if (allow_reprocess)
this->read_attribute_reprocess (attr);
break;
case DW_FORM_strx:
case DW_FORM_strx1:
case DW_FORM_strx2:
case DW_FORM_strx3:
case DW_FORM_strx4:
case DW_FORM_GNU_str_index:
{
ULONGEST str_index;
if (form == DW_FORM_strx1)
{
str_index = read_1_byte (m_abfd, info_ptr);
info_ptr += 1;
}
else if (form == DW_FORM_strx2)
{
str_index = read_2_bytes (m_abfd, info_ptr);
info_ptr += 2;
}
else if (form == DW_FORM_strx3)
{
str_index = read_3_bytes (m_abfd, info_ptr);
info_ptr += 3;
}
else if (form == DW_FORM_strx4)
{
str_index = read_4_bytes (m_abfd, info_ptr);
info_ptr += 4;
}
else
{
str_index = read_unsigned_leb128 (m_abfd, info_ptr, &bytes_read);
info_ptr += bytes_read;
}
attr->set_unsigned_reprocess (str_index);
if (allow_reprocess)
this->read_attribute_reprocess (attr);
}
break;
default:
error (_(DWARF_ERROR_PREFIX
"Cannot handle %s in DWARF reader [in module %s]"),
dwarf_form_name (form), bfd_get_filename (m_abfd));
}
/* Super hack. */
if (m_cu->per_cu->is_dwz && attr->form_is_ref ())
attr->form = DW_FORM_GNU_ref_alt;
/* We have seen instances where the compiler tried to emit a byte
size attribute of -1 which ended up being encoded as an unsigned
0xffffffff. Although 0xffffffff is technically a valid size value,
an object of this size seems pretty unlikely so we can relatively
safely treat these cases as if the size attribute was invalid and
treat them as zero by default. */
if (attr->name == DW_AT_byte_size
&& form == DW_FORM_data4
&& attr->as_unsigned () >= 0xffffffff)
{
complaint
(_("Suspicious DW_AT_byte_size value treated as zero instead of %s"),
hex_string (attr->as_unsigned ()));
attr->set_unsigned (0);
}
return info_ptr;
}
/* Read an attribute described by an abbreviated attribute. */
const gdb_byte *
cutu_reader::read_attribute (attribute *attr, const attr_abbrev *abbrev,
const gdb_byte *info_ptr, bool allow_reprocess)
{
attr->name = abbrev->name;
attr->string_is_canonical = 0;
return this->read_attribute_value (attr, abbrev->form, abbrev->implicit_const,
info_ptr, allow_reprocess);
}
/* See read.h. */
const char *
read_indirect_string_at_offset (dwarf2_per_objfile *per_objfile,
LONGEST str_offset)
{
return per_objfile->per_bfd->str.read_string (per_objfile->objfile,
str_offset, "DW_FORM_strp");
}
/* Return pointer to string at .debug_str offset as read from BUF.
BUF is assumed to be in a compilation unit described by CU_HEADER.
Return *BYTES_READ_PTR count of bytes read from BUF. */
static const char *
read_indirect_string (dwarf2_per_objfile *per_objfile, bfd *abfd,
const gdb_byte *buf,
const struct comp_unit_head *cu_header,
unsigned int *bytes_read_ptr)
{
LONGEST str_offset = cu_header->read_offset (abfd, buf, bytes_read_ptr);
return read_indirect_string_at_offset (per_objfile, str_offset);
}
/* See read.h. */
const char *
dwarf2_per_objfile::read_line_string (const gdb_byte *buf,
unsigned int offset_size)
{
bfd *abfd = objfile->obfd.get ();
ULONGEST str_offset = read_offset (abfd, buf, offset_size);
return per_bfd->line_str.read_string (objfile, str_offset, "DW_FORM_line_strp");
}
/* See read.h. */
const char *
dwarf2_per_objfile::read_line_string (const gdb_byte *buf,
const struct comp_unit_head *cu_header,
unsigned int *bytes_read_ptr)
{
bfd *abfd = objfile->obfd.get ();
LONGEST str_offset = cu_header->read_offset (abfd, buf, bytes_read_ptr);
return per_bfd->line_str.read_string (objfile, str_offset, "DW_FORM_line_strp");
}
/* Given index ADDR_INDEX in .debug_addr, fetch the value.
ADDR_BASE is the DW_AT_addr_base (DW_AT_GNU_addr_base) attribute or zero.
ADDR_SIZE is the size of addresses from the CU header. */
static unrelocated_addr
read_addr_index_1 (dwarf2_per_objfile *per_objfile, unsigned int addr_index,
std::optional<ULONGEST> addr_base, int addr_size)
{
struct objfile *objfile = per_objfile->objfile;
bfd *abfd = objfile->obfd.get ();
const gdb_byte *info_ptr;
ULONGEST addr_base_or_zero = addr_base.has_value () ? *addr_base : 0;
per_objfile->per_bfd->addr.read (objfile);
if (per_objfile->per_bfd->addr.buffer == NULL)
error (_("DW_FORM_addr_index used without .debug_addr section [in module %s]"),
objfile_name (objfile));
if (addr_base_or_zero + addr_index * addr_size
>= per_objfile->per_bfd->addr.size)
error (_("DW_FORM_addr_index pointing outside of "
".debug_addr section [in module %s]"),
objfile_name (objfile));
info_ptr = (per_objfile->per_bfd->addr.buffer + addr_base_or_zero
+ addr_index * addr_size);
if (addr_size == 4)
return (unrelocated_addr) bfd_get_32 (abfd, info_ptr);
else
return (unrelocated_addr) bfd_get_64 (abfd, info_ptr);
}
/* Given index ADDR_INDEX in .debug_addr, fetch the value. */
static unrelocated_addr
read_addr_index (struct dwarf2_cu *cu, unsigned int addr_index)
{
return read_addr_index_1 (cu->per_objfile, addr_index,
cu->addr_base, cu->header.addr_size);
}
/* Given a pointer to an leb128 value, fetch the value from .debug_addr. */
static unrelocated_addr
read_addr_index_from_leb128 (struct dwarf2_cu *cu, const gdb_byte *info_ptr,
unsigned int *bytes_read)
{
bfd *abfd = cu->per_objfile->objfile->obfd.get ();
unsigned int addr_index = read_unsigned_leb128 (abfd, info_ptr, bytes_read);
return read_addr_index (cu, addr_index);
}
/* See read.h. */
unrelocated_addr
dwarf2_read_addr_index (dwarf2_per_cu *per_cu, dwarf2_per_objfile *per_objfile,
unsigned int addr_index)
{
struct dwarf2_cu *cu = per_objfile->get_cu (per_cu);
std::optional<ULONGEST> addr_base;
int addr_size;
/* We need addr_base and addr_size.
If we don't have PER_CU->cu, we have to get it.
Nasty, but the alternative is storing the needed info in PER_CU,
which at this point doesn't seem justified: it's not clear how frequently
it would get used and it would increase the size of every PER_CU.
Entry points like dwarf2_per_cu_addr_size do a similar thing
so we're not in uncharted territory here.
Alas we need to be a bit more complicated as addr_base is contained
in the DIE.
We don't need to read the entire CU(/TU).
We just need the header and top level die.
IWBN to use the aging mechanism to let us lazily later discard the CU.
For now we skip this optimization. */
if (cu != NULL)
{
addr_base = cu->addr_base;
addr_size = cu->header.addr_size;
}
else
{
cutu_reader reader (per_cu, per_objfile, nullptr, nullptr, false,
language_minimal);
addr_base = reader.cu ()->addr_base;
addr_size = reader.cu ()->header.addr_size;
}
return read_addr_index_1 (per_objfile, addr_index, addr_base, addr_size);
}
/* Given a DW_FORM_GNU_str_index value STR_INDEX, fetch the string.
STR_SECTION, STR_OFFSETS_SECTION can be from a Fission stub or a
DWO file. */
static const char *
read_str_index (struct dwarf2_cu *cu,
struct dwarf2_section_info *str_section,
struct dwarf2_section_info *str_offsets_section,
ULONGEST str_offsets_base, ULONGEST str_index,
unsigned offset_size)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
const char *objf_name = objfile_name (objfile);
bfd *abfd = objfile->obfd.get ();
const gdb_byte *info_ptr;
ULONGEST str_offset;
static const char form_name[] = "DW_FORM_GNU_str_index or DW_FORM_strx";
str_section->read (objfile);
str_offsets_section->read (objfile);
if (str_section->buffer == NULL)
error (_("%s used without %s section"
" in CU at offset %s [in module %s]"),
form_name, str_section->get_name (),
sect_offset_str (cu->header.sect_off), objf_name);
if (str_offsets_section->buffer == NULL)
error (_("%s used without %s section"
" in CU at offset %s [in module %s]"),
form_name, str_section->get_name (),
sect_offset_str (cu->header.sect_off), objf_name);
info_ptr = (str_offsets_section->buffer
+ str_offsets_base
+ str_index * offset_size);
if (offset_size == 4)
str_offset = bfd_get_32 (abfd, info_ptr);
else
str_offset = bfd_get_64 (abfd, info_ptr);
if (str_offset >= str_section->size)
error (_("Offset from %s pointing outside of"
" %s section in CU at offset %s [in module %s]"),
form_name, str_section->get_name (),
sect_offset_str (cu->header.sect_off), objf_name);
return (const char *) (str_section->buffer + str_offset);
}
/* Given a DW_FORM_GNU_str_index from a DWO file, fetch the string. */
const char *
cutu_reader::read_dwo_str_index (ULONGEST str_index)
{
unsigned offset_size;
ULONGEST str_offsets_base;
if (m_cu->header.version >= 5)
{
/* We have a DWARF5 CU with a reference to a .debug_str_offsets section,
so assume the .debug_str_offsets section is DWARF5 as well, and
parse the header. FIXME: Parse the header only once. */
unsigned int bytes_read = 0;
bfd *abfd = m_dwo_file->sections.str_offsets.get_bfd_owner ();
const gdb_byte *p = m_dwo_file->sections.str_offsets.buffer;
/* Header: Initial length. */
read_initial_length (abfd, p + bytes_read, &bytes_read);
/* Determine offset_size based on the .debug_str_offsets header. */
const bool dwarf5_is_dwarf64 = bytes_read != 4;
offset_size = dwarf5_is_dwarf64 ? 8 : 4;
/* Header: Version. */
unsigned version = read_2_bytes (abfd, p + bytes_read);
bytes_read += 2;
if (version <= 4)
{
/* We'd like one warning here about ignoring the section, but
because we parse the header more than once (see FIXME above)
we'd have many warnings, so use a complaint instead, which at
least has a limit. */
complaint (_("Section .debug_str_offsets in %s has unsupported"
" version %d, use empty string."),
m_dwo_file->dwo_name.c_str (), version);
return "";
}
/* Header: Padding. */
bytes_read += 2;
str_offsets_base = bytes_read;
}
else
{
/* We have a pre-DWARF5 CU with a reference to a .debug_str_offsets
section, assume the .debug_str_offsets section is pre-DWARF5 as
well, which doesn't have a header. */
str_offsets_base = 0;
/* Determine offset_size based on the .debug_info header. */
offset_size = m_cu->header.offset_size;
}
return read_str_index (m_cu, &m_dwo_file->sections.str,
&m_dwo_file->sections.str_offsets, str_offsets_base,
str_index, offset_size);
}
/* Given a DW_FORM_GNU_str_index from a Fission stub, fetch the string. */
static const char *
read_stub_str_index (struct dwarf2_cu *cu, ULONGEST str_index)
{
struct objfile *objfile = cu->per_objfile->objfile;
const char *objf_name = objfile_name (objfile);
static const char form_name[] = "DW_FORM_GNU_str_index";
static const char str_offsets_attr_name[] = "DW_AT_str_offsets";
if (!cu->str_offsets_base.has_value ())
error (_("%s used in Fission stub without %s"
" in CU at offset 0x%lx [in module %s]"),
form_name, str_offsets_attr_name,
(long) cu->header.offset_size, objf_name);
return read_str_index (cu,
&cu->per_objfile->per_bfd->str,
&cu->per_objfile->per_bfd->str_offsets,
*cu->str_offsets_base, str_index,
cu->header.offset_size);
}
/* Return the length of an LEB128 number in BUF. */
static int
leb128_size (const gdb_byte *buf)
{
const gdb_byte *begin = buf;
gdb_byte byte;
while (1)
{
byte = *buf++;
if ((byte & 128) == 0)
return buf - begin;
}
}
/* Converts DWARF language names to GDB language names. */
enum language
dwarf_lang_to_enum_language (ULONGEST lang)
{
enum language language;
switch (lang)
{
case DW_LANG_C89:
case DW_LANG_C99:
case DW_LANG_C11:
case DW_LANG_C17:
case DW_LANG_C23:
case DW_LANG_C:
case DW_LANG_UPC:
language = language_c;
break;
case DW_LANG_Java:
case DW_LANG_C_plus_plus:
case DW_LANG_C_plus_plus_11:
case DW_LANG_C_plus_plus_14:
case DW_LANG_C_plus_plus_17:
case DW_LANG_C_plus_plus_20:
case DW_LANG_C_plus_plus_23:
language = language_cplus;
break;
case DW_LANG_D:
language = language_d;
break;
case DW_LANG_Fortran77:
case DW_LANG_Fortran90:
case DW_LANG_Fortran95:
case DW_LANG_Fortran03:
case DW_LANG_Fortran08:
case DW_LANG_Fortran18:
case DW_LANG_Fortran23:
language = language_fortran;
break;
case DW_LANG_Go:
language = language_go;
break;
case DW_LANG_Assembly:
case DW_LANG_Mips_Assembler:
language = language_asm;
break;
case DW_LANG_Ada83:
case DW_LANG_Ada95:
case DW_LANG_Ada2005:
case DW_LANG_Ada2012:
language = language_ada;
break;
case DW_LANG_Modula2:
language = language_m2;
break;
case DW_LANG_Pascal83:
language = language_pascal;
break;
case DW_LANG_ObjC:
language = language_objc;
break;
case DW_LANG_Rust:
case DW_LANG_Rust_old:
language = language_rust;
break;
case DW_LANG_OpenCL:
language = language_opencl;
break;
case DW_LANG_Cobol74:
case DW_LANG_Cobol85:
default:
language = language_minimal;
break;
}
return language;
}
/* Return the NAME attribute of DIE in *CU, or return NULL if not there. Also
return in *CU the cu in which the attribute was actually found. */
static struct attribute *
dwarf2_attr (struct die_info *die, unsigned int name, struct dwarf2_cu **cu)
{
for (;;)
{
unsigned int i;
struct attribute *spec = NULL;
for (i = 0; i < die->num_attrs; ++i)
{
if (die->attrs[i].name == name)
return &die->attrs[i];
if (die->attrs[i].name == DW_AT_specification
|| die->attrs[i].name == DW_AT_abstract_origin)
spec = &die->attrs[i];
}
if (!spec)
break;
struct die_info *prev_die = die;
die = follow_die_ref (die, spec, cu);
if (die == prev_die)
/* Self-reference, we're done. */
break;
}
return NULL;
}
/* Return the NAME attribute of DIE in CU, or return NULL if not there. */
static struct attribute *
dwarf2_attr (struct die_info *die, unsigned int name, struct dwarf2_cu *cu)
{
return dwarf2_attr (die, name, &cu);
}
/* Return the string associated with a string-typed attribute, or NULL if it
is either not found or is of an incorrect type. */
static const char *
dwarf2_string_attr (struct die_info *die, unsigned int name, struct dwarf2_cu *cu)
{
struct attribute *attr;
const char *str = NULL;
attr = dwarf2_attr (die, name, cu);
if (attr != NULL)
{
str = attr->as_string ();
if (str == nullptr)
complaint (_("string type expected for attribute %s for "
"DIE at %s [in module %s]"),
dwarf_attr_name (name), sect_offset_str (die->sect_off),
objfile_name (cu->per_objfile->objfile));
}
return str;
}
/* Return the dwo name or NULL if not present. If present, it is in either
DW_AT_GNU_dwo_name or DW_AT_dwo_name attribute. */
static const char *
dwarf2_dwo_name (struct die_info *die, struct dwarf2_cu *cu)
{
const char *dwo_name = dwarf2_string_attr (die, DW_AT_GNU_dwo_name, cu);
if (dwo_name == nullptr)
dwo_name = dwarf2_string_attr (die, DW_AT_dwo_name, cu);
return dwo_name;
}
/* Return non-zero iff the attribute NAME is defined for the given DIE,
and holds a non-zero value. This function should only be used for
DW_FORM_flag or DW_FORM_flag_present attributes. */
static int
dwarf2_flag_true_p (struct die_info *die, unsigned name, struct dwarf2_cu *cu)
{
struct attribute *attr = dwarf2_attr (die, name, cu);
return attr != nullptr && attr->as_boolean ();
}
static int
die_is_declaration (struct die_info *die, struct dwarf2_cu *cu)
{
/* A DIE is a declaration if it has a DW_AT_declaration attribute
which value is non-zero. However, we have to be careful with
DIEs having a DW_AT_specification attribute, because dwarf2_attr()
(via dwarf2_flag_true_p) follows this attribute. So we may
end up accidentally finding a declaration attribute that belongs
to a different DIE referenced by the specification attribute,
even though the given DIE does not have a declaration attribute. */
return (dwarf2_flag_true_p (die, DW_AT_declaration, cu)
&& dwarf2_attr (die, DW_AT_specification, cu) == NULL);
}
/* Return the die giving the specification for DIE, if there is
one. *SPEC_CU is the CU containing DIE on input, and the CU
containing the return value on output. If there is no
specification, but there is an abstract origin, that is
returned. */
static struct die_info *
die_specification (struct die_info *die, struct dwarf2_cu **spec_cu)
{
struct attribute *spec_attr = dwarf2_attr (die, DW_AT_specification,
*spec_cu);
if (spec_attr == NULL)
spec_attr = dwarf2_attr (die, DW_AT_abstract_origin, *spec_cu);
if (spec_attr == NULL)
return NULL;
else
return follow_die_ref (die, spec_attr, spec_cu);
}
/* A convenience function to find the proper .debug_line section for a CU. */
static struct dwarf2_section_info *
get_debug_line_section (struct dwarf2_cu *cu)
{
struct dwarf2_section_info *section;
dwarf2_per_objfile *per_objfile = cu->per_objfile;
/* For TUs in DWO files, the DW_AT_stmt_list attribute lives in the
DWO file. */
if (cu->dwo_unit && cu->per_cu->is_debug_types)
section = &cu->dwo_unit->dwo_file->sections.line;
else if (cu->per_cu->is_dwz)
section = &per_objfile->per_bfd->get_dwz_file (true)->line;
else
section = &per_objfile->per_bfd->line;
return section;
}
/* Read the statement program header starting at OFFSET in
.debug_line, or .debug_line.dwo. Return a pointer
to a struct line_header, allocated using xmalloc.
Returns NULL if there is a problem reading the header, e.g., if it
has a version we don't understand.
NOTE: the strings in the include directory and file name tables of
the returned object point into the dwarf line section buffer,
and must not be freed. */
static line_header_up
dwarf_decode_line_header (sect_offset sect_off, struct dwarf2_cu *cu,
const char *comp_dir)
{
struct dwarf2_section_info *section;
dwarf2_per_objfile *per_objfile = cu->per_objfile;
section = get_debug_line_section (cu);
section->read (per_objfile->objfile);
if (section->buffer == NULL)
{
if (cu->dwo_unit && cu->per_cu->is_debug_types)
complaint (_("missing .debug_line.dwo section"));
else
complaint (_("missing .debug_line section"));
return 0;
}
return dwarf_decode_line_header (sect_off, cu->per_cu->is_dwz,
per_objfile, section, &cu->header,
comp_dir);
}
/* Subroutine of dwarf_decode_lines to simplify it.
Return the file name for the given file_entry.
CU_INFO describes the CU's DW_AT_name and DW_AT_comp_dir.
If space for the result is malloc'd, *NAME_HOLDER will be set.
Returns NULL if FILE_INDEX should be ignored, i.e., it is
equivalent to CU_INFO. */
static const char *
compute_include_file_name (const struct line_header *lh, const file_entry &fe,
const file_and_directory &cu_info,
std::string &name_holder)
{
const char *include_name = fe.name;
const char *include_name_to_compare = include_name;
const char *dir_name = fe.include_dir (lh);
std::string hold_compare;
if (!IS_ABSOLUTE_PATH (include_name)
&& (dir_name != nullptr || cu_info.get_comp_dir () != nullptr))
{
/* Avoid creating a duplicate name for CU_INFO.
We do this by comparing INCLUDE_NAME and CU_INFO.
Before we do the comparison, however, we need to account
for DIR_NAME and COMP_DIR.
First prepend dir_name (if non-NULL). If we still don't
have an absolute path prepend comp_dir (if non-NULL).
However, the directory we record in the include-file's
psymtab does not contain COMP_DIR (to match the
corresponding symtab(s)).
Example:
bash$ cd /tmp
bash$ gcc -g ./hello.c
include_name = "hello.c"
dir_name = "."
DW_AT_comp_dir = comp_dir = "/tmp"
DW_AT_name = "./hello.c"
*/
if (dir_name != NULL)
{
name_holder = path_join (dir_name, include_name);
include_name = name_holder.c_str ();
include_name_to_compare = include_name;
}
if (!IS_ABSOLUTE_PATH (include_name)
&& cu_info.get_comp_dir () != nullptr)
{
hold_compare = path_join (cu_info.get_comp_dir (), include_name);
include_name_to_compare = hold_compare.c_str ();
}
}
std::string copied_name;
const char *cu_filename = cu_info.get_name ();
if (!IS_ABSOLUTE_PATH (cu_filename) && cu_info.get_comp_dir () != nullptr)
{
copied_name = path_join (cu_info.get_comp_dir (), cu_filename);
cu_filename = copied_name.c_str ();
}
if (FILENAME_CMP (include_name_to_compare, cu_filename) == 0)
return nullptr;
return include_name;
}
/* State machine to track the state of the line number program. */
class lnp_state_machine
{
public:
/* Initialize a machine state for the start of a line number
program. */
lnp_state_machine (struct dwarf2_cu *cu, gdbarch *arch, line_header *lh);
file_entry *current_file ()
{
/* lh->file_names is 0-based, but the file name numbers in the
statement program are 1-based. */
return m_line_header->file_name_at (m_file);
}
/* Record the line in the state machine. END_SEQUENCE is true if
we're processing the end of a sequence. */
void record_line (bool end_sequence);
/* Check ADDRESS is -1, -2, or zero and less than UNRELOCATED_LOWPC, and if
true nop-out rest of the lines in this sequence. */
void check_line_address (struct dwarf2_cu *cu,
const gdb_byte *line_ptr,
unrelocated_addr unrelocated_lowpc,
unrelocated_addr address);
void handle_set_discriminator (unsigned int discriminator)
{
m_discriminator = discriminator;
m_line_has_non_zero_discriminator |= discriminator != 0;
}
/* Handle DW_LNE_set_address. */
void handle_set_address (unrelocated_addr address)
{
m_op_index = 0;
m_address
= (unrelocated_addr) gdbarch_adjust_dwarf2_line (m_gdbarch,
(CORE_ADDR) address,
false);
}
/* Handle DW_LNS_advance_pc. */
void handle_advance_pc (CORE_ADDR adjust);
/* Handle a special opcode. */
void handle_special_opcode (unsigned char op_code);
/* Handle DW_LNS_advance_line. */
void handle_advance_line (int line_delta)
{
advance_line (line_delta);
}
/* Handle DW_LNS_set_file. */
void handle_set_file (file_name_index file);
/* Handle DW_LNS_negate_stmt. */
void handle_negate_stmt ()
{
m_flags ^= LEF_IS_STMT;
}
/* Handle DW_LNS_const_add_pc. */
void handle_const_add_pc ();
/* Handle DW_LNS_fixed_advance_pc. */
void handle_fixed_advance_pc (CORE_ADDR addr_adj)
{
addr_adj = gdbarch_adjust_dwarf2_line (m_gdbarch, addr_adj, true);
m_address = (unrelocated_addr) ((CORE_ADDR) m_address + addr_adj);
m_op_index = 0;
}
/* Handle DW_LNS_copy. */
void handle_copy ()
{
record_line (false);
m_discriminator = 0;
m_flags &= ~LEF_PROLOGUE_END;
m_flags &= ~LEF_EPILOGUE_BEGIN;
}
/* Handle DW_LNE_end_sequence. */
void handle_end_sequence ()
{
m_currently_recording_lines = true;
}
/* Handle DW_LNS_set_prologue_end. */
void handle_set_prologue_end ()
{
m_flags |= LEF_PROLOGUE_END;
}
void handle_set_epilogue_begin ()
{
m_flags |= LEF_EPILOGUE_BEGIN;
}
private:
/* Advance the line by LINE_DELTA. */
void advance_line (int line_delta)
{
m_line += line_delta;
if (line_delta != 0)
m_line_has_non_zero_discriminator = m_discriminator != 0;
}
struct dwarf2_cu *m_cu;
gdbarch *m_gdbarch;
/* The line number header. */
line_header *m_line_header;
/* These are part of the standard DWARF line number state machine,
and initialized according to the DWARF spec. */
unsigned char m_op_index = 0;
/* The line table index of the current file. */
file_name_index m_file = 1;
unsigned int m_line = 1;
/* These are initialized in the constructor. */
unrelocated_addr m_address;
linetable_entry_flags m_flags;
unsigned int m_discriminator = 0;
/* Additional bits of state we need to track. */
/* The last file a line number was recorded for. */
struct subfile *m_last_subfile = NULL;
/* The address of the last line entry. */
unrelocated_addr m_last_address;
/* Set to true when a previous line at the same address (using
m_last_address) had LEF_IS_STMT set in m_flags. This is reset to false
when a line entry at a new address (m_address different to
m_last_address) is processed. */
bool m_stmt_at_address = false;
/* When true, record the lines we decode. */
bool m_currently_recording_lines = true;
/* The last line number that was recorded, used to coalesce
consecutive entries for the same line. This can happen, for
example, when discriminators are present. PR 17276. */
unsigned int m_last_line = 0;
bool m_line_has_non_zero_discriminator = false;
};
void
lnp_state_machine::handle_advance_pc (CORE_ADDR adjust)
{
CORE_ADDR addr_adj = (((m_op_index + adjust)
/ m_line_header->maximum_ops_per_instruction)
* m_line_header->minimum_instruction_length);
addr_adj = gdbarch_adjust_dwarf2_line (m_gdbarch, addr_adj, true);
m_address = (unrelocated_addr) ((CORE_ADDR) m_address + addr_adj);
m_op_index = ((m_op_index + adjust)
% m_line_header->maximum_ops_per_instruction);
}
void
lnp_state_machine::handle_special_opcode (unsigned char op_code)
{
unsigned char adj_opcode = op_code - m_line_header->opcode_base;
unsigned char adj_opcode_d = adj_opcode / m_line_header->line_range;
unsigned char adj_opcode_r = adj_opcode % m_line_header->line_range;
CORE_ADDR addr_adj = (((m_op_index + adj_opcode_d)
/ m_line_header->maximum_ops_per_instruction)
* m_line_header->minimum_instruction_length);
addr_adj = gdbarch_adjust_dwarf2_line (m_gdbarch, addr_adj, true);
m_address = (unrelocated_addr) ((CORE_ADDR) m_address + addr_adj);
m_op_index = ((m_op_index + adj_opcode_d)
% m_line_header->maximum_ops_per_instruction);
int line_delta = m_line_header->line_base + adj_opcode_r;
advance_line (line_delta);
record_line (false);
m_discriminator = 0;
m_flags &= ~LEF_PROLOGUE_END;
m_flags &= ~LEF_EPILOGUE_BEGIN;
}
void
lnp_state_machine::handle_set_file (file_name_index file)
{
m_file = file;
const file_entry *fe = current_file ();
if (fe == NULL)
dwarf2_debug_line_missing_file_complaint ();
else
{
m_line_has_non_zero_discriminator = m_discriminator != 0;
dwarf2_start_subfile (m_cu, *fe, *m_line_header);
}
}
void
lnp_state_machine::handle_const_add_pc ()
{
CORE_ADDR adjust
= (255 - m_line_header->opcode_base) / m_line_header->line_range;
CORE_ADDR addr_adj
= (((m_op_index + adjust)
/ m_line_header->maximum_ops_per_instruction)
* m_line_header->minimum_instruction_length);
addr_adj = gdbarch_adjust_dwarf2_line (m_gdbarch, addr_adj, true);
m_address = (unrelocated_addr) ((CORE_ADDR) m_address + addr_adj);
m_op_index = ((m_op_index + adjust)
% m_line_header->maximum_ops_per_instruction);
}
/* Return non-zero if we should add LINE to the line number table.
LINE is the line to add, LAST_LINE is the last line that was added,
LAST_SUBFILE is the subfile for LAST_LINE.
LINE_HAS_NON_ZERO_DISCRIMINATOR is non-zero if LINE has ever
had a non-zero discriminator.
We have to be careful in the presence of discriminators.
E.g., for this line:
for (i = 0; i < 100000; i++);
clang can emit four line number entries for that one line,
each with a different discriminator.
See gdb.dwarf2/dw2-single-line-discriminators.exp for an example.
However, we want gdb to coalesce all four entries into one.
Otherwise the user could stepi into the middle of the line and
gdb would get confused about whether the pc really was in the
middle of the line.
Things are further complicated by the fact that two consecutive
line number entries for the same line is a heuristic used by gcc
to denote the end of the prologue. So we can't just discard duplicate
entries, we have to be selective about it. The heuristic we use is
that we only collapse consecutive entries for the same line if at least
one of those entries has a non-zero discriminator. PR 17276.
Note: Addresses in the line number state machine can never go backwards
within one sequence, thus this coalescing is ok. */
static int
dwarf_record_line_p (struct dwarf2_cu *cu,
unsigned int line, unsigned int last_line,
int line_has_non_zero_discriminator,
struct subfile *last_subfile)
{
if (cu->get_builder ()->get_current_subfile () != last_subfile)
return 1;
if (line != last_line)
return 1;
/* Same line for the same file that we've seen already.
As a last check, for pr 17276, only record the line if the line
has never had a non-zero discriminator. */
if (!line_has_non_zero_discriminator)
return 1;
return 0;
}
/* Use the CU's builder to record line number LINE beginning at
address ADDRESS in the line table of subfile SUBFILE. */
static void
dwarf_record_line_1 (struct gdbarch *gdbarch, struct subfile *subfile,
unsigned int line, unrelocated_addr address,
linetable_entry_flags flags,
struct dwarf2_cu *cu)
{
unrelocated_addr addr
= unrelocated_addr (gdbarch_addr_bits_remove (gdbarch,
(CORE_ADDR) address));
if (cu != nullptr)
{
if (dwarf_line_debug)
gdb_printf (gdb_stdlog, "Recording line %u, file %s, address %s\n",
line, lbasename (subfile->name.c_str ()),
paddress (gdbarch, (CORE_ADDR) address));
cu->get_builder ()->record_line (subfile, line, addr, flags);
}
}
/* Subroutine of dwarf_decode_lines_1 to simplify it.
Mark the end of a set of line number records.
The arguments are the same as for dwarf_record_line_1.
If SUBFILE is NULL the request is ignored. */
static void
dwarf_finish_line (struct gdbarch *gdbarch, struct subfile *subfile,
unrelocated_addr address, struct dwarf2_cu *cu)
{
if (subfile == NULL)
return;
if (dwarf_line_debug)
{
gdb_printf (gdb_stdlog,
"Finishing current line, file %s, address %s\n",
lbasename (subfile->name.c_str ()),
paddress (gdbarch, (CORE_ADDR) address));
}
dwarf_record_line_1 (gdbarch, subfile, 0, address, LEF_IS_STMT, cu);
}
void
lnp_state_machine::record_line (bool end_sequence)
{
if (dwarf_line_debug)
{
gdb_printf (gdb_stdlog,
"Processing actual line %u: file %u,"
" address %s, is_stmt %u, prologue_end %u,"
" epilogue_begin %u, discrim %u%s\n",
m_line, m_file,
paddress (m_gdbarch, (CORE_ADDR) m_address),
(m_flags & LEF_IS_STMT) != 0,
(m_flags & LEF_PROLOGUE_END) != 0,
(m_flags & LEF_EPILOGUE_BEGIN) != 0,
m_discriminator,
(end_sequence ? "\t(end sequence)" : ""));
}
file_entry *fe = current_file ();
if (fe == NULL)
dwarf2_debug_line_missing_file_complaint ();
/* For now we ignore lines not starting on an instruction boundary.
But not when processing end_sequence for compatibility with the
previous version of the code. */
else if (m_op_index == 0 || end_sequence)
{
/* When we switch files we insert an end maker in the first file,
switch to the second file and add a new line entry. The
problem is that the end marker inserted in the first file will
discard any previous line entries at the same address. If the
line entries in the first file are marked as is-stmt, while
the new line in the second file is non-stmt, then this means
the end marker will discard is-stmt lines so we can have a
non-stmt line. This means that there are less addresses at
which the user can insert a breakpoint.
To improve this we track the last address in m_last_address,
and whether we have seen an is-stmt at this address. Then
when switching files, if we have seen a stmt at the current
address, and we are switching to create a non-stmt line, then
discard the new line. */
bool file_changed
= m_last_subfile != m_cu->get_builder ()->get_current_subfile ();
bool ignore_this_line
= ((file_changed && !end_sequence && m_last_address == m_address
&& ((m_flags & LEF_IS_STMT) == 0)
&& m_stmt_at_address)
|| (!end_sequence && m_line == 0));
if ((file_changed && !ignore_this_line) || end_sequence)
{
dwarf_finish_line (m_gdbarch, m_last_subfile, m_address,
m_currently_recording_lines ? m_cu : nullptr);
}
if (!end_sequence && !ignore_this_line)
{
linetable_entry_flags lte_flags = m_flags;
if (m_cu->producer_is_codewarrior ())
lte_flags |= LEF_IS_STMT;
if (dwarf_record_line_p (m_cu, m_line, m_last_line,
m_line_has_non_zero_discriminator,
m_last_subfile))
{
buildsym_compunit *builder = m_cu->get_builder ();
dwarf_record_line_1 (m_gdbarch,
builder->get_current_subfile (),
m_line, m_address, lte_flags,
m_currently_recording_lines ? m_cu : nullptr);
m_last_subfile = m_cu->get_builder ()->get_current_subfile ();
m_last_line = m_line;
}
}
}
/* Track whether we have seen any IS_STMT true at m_address in case we
have multiple line table entries all at m_address. */
if (m_last_address != m_address)
{
m_stmt_at_address = false;
m_last_address = m_address;
}
m_stmt_at_address |= (m_flags & LEF_IS_STMT) != 0;
}
lnp_state_machine::lnp_state_machine (struct dwarf2_cu *cu, gdbarch *arch,
line_header *lh)
: m_cu (cu),
m_gdbarch (arch),
m_line_header (lh),
/* Call `gdbarch_adjust_dwarf2_line' on the initial 0 address as
if there was a line entry for it so that the backend has a
chance to adjust it and also record it in case it needs it.
This is currently used by MIPS code,
cf. `mips_adjust_dwarf2_line'. */
m_address ((unrelocated_addr) gdbarch_adjust_dwarf2_line (arch, 0, 0)),
m_flags (lh->default_is_stmt ? LEF_IS_STMT : (linetable_entry_flags) 0),
m_last_address (m_address)
{
}
void
lnp_state_machine::check_line_address (struct dwarf2_cu *cu,
const gdb_byte *line_ptr,
unrelocated_addr unrelocated_lowpc,
unrelocated_addr address)
{
/* Linkers resolve a symbolic relocation referencing a GC'd function to 0,
-1 or -2 (-2 is used by certain lld versions, see
https://github.com/llvm/llvm-project/commit/e618ccbf431f6730edb6d1467a127c3a52fd57f7).
If ADDRESS is 0, ignoring the opcode will err if the text section is
located at 0x0. In this case, additionally check that if
ADDRESS < UNRELOCATED_LOWPC. */
if ((address == (unrelocated_addr) 0 && address < unrelocated_lowpc)
|| address == (unrelocated_addr) -1
|| address == (unrelocated_addr) -2)
{
/* This line table is for a function which has been
GCd by the linker. Ignore it. PR gdb/12528 */
struct objfile *objfile = cu->per_objfile->objfile;
long line_offset = line_ptr - get_debug_line_section (cu)->buffer;
complaint (_(".debug_line address at offset 0x%lx is 0 [in module %s]"),
line_offset, objfile_name (objfile));
m_currently_recording_lines = false;
/* Note: m_currently_recording_lines is left as false until we see
DW_LNE_end_sequence. */
}
}
/* Subroutine of dwarf_decode_lines to simplify it.
Process the line number information in LH. */
static void
dwarf_decode_lines_1 (struct line_header *lh, struct dwarf2_cu *cu,
unrelocated_addr lowpc)
{
const gdb_byte *line_ptr, *extended_end;
const gdb_byte *line_end;
unsigned int bytes_read, extended_len;
unsigned char op_code, extended_op;
struct objfile *objfile = cu->per_objfile->objfile;
bfd *abfd = objfile->obfd.get ();
struct gdbarch *gdbarch = objfile->arch ();
line_ptr = lh->statement_program_start;
line_end = lh->statement_program_end;
/* Read the statement sequences until there's nothing left. */
while (line_ptr < line_end)
{
/* The DWARF line number program state machine. Reset the state
machine at the start of each sequence. */
lnp_state_machine state_machine (cu, gdbarch, lh);
bool end_sequence = false;
/* Start a subfile for the current file of the state
machine. */
const file_entry *fe = state_machine.current_file ();
if (fe != NULL)
dwarf2_start_subfile (cu, *fe, *lh);
/* Decode the table. */
while (line_ptr < line_end && !end_sequence)
{
op_code = read_1_byte (abfd, line_ptr);
line_ptr += 1;
if (op_code >= lh->opcode_base)
{
/* Special opcode. */
state_machine.handle_special_opcode (op_code);
}
else switch (op_code)
{
case DW_LNS_extended_op:
extended_len = read_unsigned_leb128 (abfd, line_ptr,
&bytes_read);
line_ptr += bytes_read;
extended_end = line_ptr + extended_len;
extended_op = read_1_byte (abfd, line_ptr);
line_ptr += 1;
if (DW_LNE_lo_user <= extended_op
&& extended_op <= DW_LNE_hi_user)
{
/* Vendor extension, ignore. */
line_ptr = extended_end;
break;
}
switch (extended_op)
{
case DW_LNE_end_sequence:
state_machine.handle_end_sequence ();
end_sequence = true;
break;
case DW_LNE_set_address:
{
unrelocated_addr address
= cu->header.read_address (abfd, line_ptr, &bytes_read);
line_ptr += bytes_read;
state_machine.check_line_address (cu, line_ptr, lowpc,
address);
state_machine.handle_set_address (address);
}
break;
case DW_LNE_define_file:
{
const char *cur_file;
unsigned int mod_time, length;
dir_index dindex;
cur_file = read_direct_string (abfd, line_ptr,
&bytes_read);
line_ptr += bytes_read;
dindex = (dir_index)
read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
line_ptr += bytes_read;
mod_time =
read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
line_ptr += bytes_read;
length =
read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
line_ptr += bytes_read;
lh->add_file_name (cur_file, dindex, mod_time, length);
}
break;
case DW_LNE_set_discriminator:
{
/* The discriminator is not interesting to the
debugger; just ignore it. We still need to
check its value though:
if there are consecutive entries for the same
(non-prologue) line we want to coalesce them.
PR 17276. */
unsigned int discr
= read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
line_ptr += bytes_read;
state_machine.handle_set_discriminator (discr);
}
break;
default:
complaint (_("mangled .debug_line section"));
return;
}
/* Make sure that we parsed the extended op correctly. If e.g.
we expected a different address size than the producer used,
we may have read the wrong number of bytes. */
if (line_ptr != extended_end)
{
complaint (_("mangled .debug_line section"));
return;
}
break;
case DW_LNS_copy:
state_machine.handle_copy ();
break;
case DW_LNS_advance_pc:
{
CORE_ADDR adjust
= read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
line_ptr += bytes_read;
state_machine.handle_advance_pc (adjust);
}
break;
case DW_LNS_advance_line:
{
int line_delta
= read_signed_leb128 (abfd, line_ptr, &bytes_read);
line_ptr += bytes_read;
state_machine.handle_advance_line (line_delta);
}
break;
case DW_LNS_set_file:
{
file_name_index file
= (file_name_index) read_unsigned_leb128 (abfd, line_ptr,
&bytes_read);
line_ptr += bytes_read;
state_machine.handle_set_file (file);
}
break;
case DW_LNS_set_column:
(void) read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
line_ptr += bytes_read;
break;
case DW_LNS_negate_stmt:
state_machine.handle_negate_stmt ();
break;
case DW_LNS_set_basic_block:
break;
/* Add to the address register of the state machine the
address increment value corresponding to special opcode
255. I.e., this value is scaled by the minimum
instruction length since special opcode 255 would have
scaled the increment. */
case DW_LNS_const_add_pc:
state_machine.handle_const_add_pc ();
break;
case DW_LNS_fixed_advance_pc:
{
CORE_ADDR addr_adj = read_2_bytes (abfd, line_ptr);
line_ptr += 2;
state_machine.handle_fixed_advance_pc (addr_adj);
}
break;
case DW_LNS_set_prologue_end:
state_machine.handle_set_prologue_end ();
break;
case DW_LNS_set_epilogue_begin:
state_machine.handle_set_epilogue_begin ();
break;
default:
{
/* Unknown standard opcode, ignore it. */
int i;
for (i = 0; i < lh->standard_opcode_lengths[op_code]; i++)
{
(void) read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
line_ptr += bytes_read;
}
}
}
}
if (!end_sequence)
dwarf2_debug_line_missing_end_sequence_complaint ();
/* We got a DW_LNE_end_sequence (or we ran off the end of the buffer,
in which case we still finish recording the last line). */
state_machine.record_line (true);
}
}
/* Decode the Line Number Program (LNP) for the given line_header
structure and CU. The actual information extracted and the type
of structures created from the LNP depends on the value of PST.
FND holds the CU file name and directory, if known.
It is used for relative paths in the line table.
NOTE: It is important that psymtabs have the same file name (via
strcmp) as the corresponding symtab. Since the directory is not
used in the name of the symtab we don't use it in the name of the
psymtabs we create. E.g. expand_line_sal requires this when
finding psymtabs to expand. A good testcase for this is
mb-inline.exp.
LOWPC is the lowest address in CU (or 0 if not known).
Boolean DECODE_MAPPING specifies we need to fully decode .debug_line
for its PC<->lines mapping information. Otherwise only the filename
table is read in. */
static void
dwarf_decode_lines (struct line_header *lh, struct dwarf2_cu *cu,
unrelocated_addr lowpc, int decode_mapping)
{
if (decode_mapping)
dwarf_decode_lines_1 (lh, cu, lowpc);
/* Make sure a symtab is created for every file, even files
which contain only variables (i.e. no code with associated
line numbers). */
buildsym_compunit *builder = cu->get_builder ();
struct compunit_symtab *cust = builder->get_compunit_symtab ();
for (auto &fe : lh->file_names ())
{
dwarf2_start_subfile (cu, fe, *lh);
subfile *sf = builder->get_current_subfile ();
if (sf->symtab == nullptr)
sf->symtab = allocate_symtab (cust, sf->name.c_str (),
sf->name_for_id.c_str ());
fe.symtab = sf->symtab;
}
}
/* Start a subfile for DWARF. FILENAME is the name of the file and
DIRNAME the name of the source directory which contains FILENAME
or NULL if not known.
This routine tries to keep line numbers from identical absolute and
relative file names in a common subfile.
Using the `list' example from the GDB testsuite, which resides in
/srcdir and compiling it with Irix6.2 cc in /compdir using a filename
of /srcdir/list0.c yields the following debugging information for list0.c:
DW_AT_name: /srcdir/list0.c
DW_AT_comp_dir: /compdir
files.files[0].name: list0.h
files.files[0].dir: /srcdir
files.files[1].name: list0.c
files.files[1].dir: /srcdir
The line number information for list0.c has to end up in a single
subfile, so that `break /srcdir/list0.c:1' works as expected.
start_subfile will ensure that this happens provided that we pass the
concatenation of files.files[1].dir and files.files[1].name as the
subfile's name. */
static void
dwarf2_start_subfile (dwarf2_cu *cu, const file_entry &fe,
const line_header &lh)
{
std::string filename_holder;
const char *filename = fe.name;
const char *dirname = lh.include_dir_at (fe.d_index);
/* In order not to lose the line information directory,
we concatenate it to the filename when it makes sense.
Note that the Dwarf3 standard says (speaking of filenames in line
information): ``The directory index is ignored for file names
that represent full path names''. Thus ignoring dirname in the
`else' branch below isn't an issue. */
if (!IS_ABSOLUTE_PATH (filename) && dirname != NULL)
{
filename_holder = path_join (dirname, filename);
filename = filename_holder.c_str ();
}
std::string filename_for_id = lh.file_file_name (fe);
cu->get_builder ()->start_subfile (filename, filename_for_id.c_str ());
}
static void
var_decode_location (struct attribute *attr, struct symbol *sym,
struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
struct comp_unit_head *cu_header = &cu->header;
/* NOTE drow/2003-01-30: There used to be a comment and some special
code here to turn a symbol with DW_AT_external and a
SYMBOL_VALUE_ADDRESS of 0 into a LOC_UNRESOLVED symbol. This was
necessary for platforms (maybe Alpha, certainly PowerPC GNU/Linux
with some versions of binutils) where shared libraries could have
relocations against symbols in their debug information - the
minimal symbol would have the right address, but the debug info
would not. It's no longer necessary, because we will explicitly
apply relocations when we read in the debug information now. */
/* A DW_AT_location attribute with no contents indicates that a
variable has been optimized away. */
if (attr->form_is_block () && attr->as_block ()->size == 0)
{
sym->set_aclass_index (LOC_OPTIMIZED_OUT);
return;
}
/* Handle one degenerate form of location expression specially, to
preserve GDB's previous behavior when section offsets are
specified. If this is just a DW_OP_addr, DW_OP_addrx, or
DW_OP_GNU_addr_index then mark this symbol as LOC_STATIC. */
if (attr->form_is_block ())
{
struct dwarf_block *block = attr->as_block ();
if ((block->data[0] == DW_OP_addr
&& block->size == 1 + cu_header->addr_size)
|| ((block->data[0] == DW_OP_GNU_addr_index
|| block->data[0] == DW_OP_addrx)
&& (block->size
== 1 + leb128_size (&block->data[1]))))
{
unsigned int dummy;
unrelocated_addr tem;
if (block->data[0] == DW_OP_addr)
tem = cu->header.read_address (objfile->obfd.get (),
block->data + 1,
&dummy);
else
tem = read_addr_index_from_leb128 (cu, block->data + 1, &dummy);
sym->set_value_address ((CORE_ADDR) tem);
sym->set_aclass_index (LOC_STATIC);
fixup_symbol_section (sym, objfile);
sym->set_value_address
(sym->value_address ()
+ objfile->section_offsets[sym->section_index ()]);
return;
}
}
/* NOTE drow/2002-01-30: It might be worthwhile to have a static
expression evaluator, and use LOC_COMPUTED only when necessary
(i.e. when the value of a register or memory location is
referenced, or a thread-local block, etc.). Then again, it might
not be worthwhile. I'm assuming that it isn't unless performance
or memory numbers show me otherwise. */
dwarf2_symbol_mark_computed (attr, sym, cu, 0);
if (sym->computed_ops ()->location_has_loclist)
cu->has_loclist = true;
}
/* A helper function to add an "export" symbol. The new symbol starts
as a clone of ORIG, but is modified to defer to the symbol named
ORIG_NAME. The original symbol uses the name given in the source
code, and the symbol that is created here uses the linkage name as
its name. See ada-imported.c. */
static void
add_ada_export_symbol (struct symbol *orig, const char *new_name,
const char *orig_name, struct dwarf2_cu *cu,
struct pending **list_to_add)
{
struct symbol *copy
= new (&cu->per_objfile->objfile->objfile_obstack) symbol (*orig);
copy->set_linkage_name (new_name);
SYMBOL_LOCATION_BATON (copy) = (void *) orig_name;
copy->set_aclass_index (copy->aclass () == LOC_BLOCK
? ada_block_index
: ada_imported_index);
add_symbol_to_list (copy, list_to_add);
}
/* A helper function that decides if a given symbol is an Ada Pragma
Import or Pragma Export. */
static bool
is_ada_import_or_export (dwarf2_cu *cu, const char *name,
const char *linkagename)
{
return (cu->lang () == language_ada
&& linkagename != nullptr
&& !streq (name, linkagename)
/* The following exclusions are necessary because symbols
with names or linkage names that match here will meet the
other criteria but are not in fact caused by Pragma
Import or Pragma Export, and applying the import/export
treatment to them will introduce problems. Some of these
checks only apply to functions, but it is simpler and
harmless to always do them all. */
&& !startswith (name, "__builtin")
&& !startswith (linkagename, "___ghost_")
&& !startswith (linkagename, "__gnat")
&& !startswith (linkagename, "_ada_")
&& !streq (linkagename, "adainit"));
}
/* Given a pointer to a DWARF information entry, figure out if we need
to make a symbol table entry for it, and if so, create a new entry
and return a pointer to it.
If TYPE is NULL, determine symbol type from the die, otherwise
used the passed type.
If SPACE is not NULL, use it to hold the new symbol. If it is
NULL, allocate a new symbol on the objfile's obstack. */
static struct symbol *
new_symbol (struct die_info *die, struct type *type, struct dwarf2_cu *cu,
struct symbol *space)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct symbol *sym = NULL;
const char *name;
struct attribute *attr = NULL;
struct attribute *attr2 = NULL;
struct pending **list_to_add = NULL;
int inlined_func = (die->tag == DW_TAG_inlined_subroutine);
name = dwarf2_name (die, cu);
if (name == nullptr && (die->tag == DW_TAG_subprogram
|| die->tag == DW_TAG_inlined_subroutine
|| die->tag == DW_TAG_entry_point))
name = dw2_linkage_name (die, cu);
if (name)
{
int suppress_add = 0;
if (space)
sym = space;
else
sym = new (&objfile->objfile_obstack) symbol;
OBJSTAT (objfile, n_syms++);
/* Cache this symbol's name and the name's demangled form (if any). */
sym->set_language (cu->lang (), &objfile->objfile_obstack);
/* Fortran does not have mangling standard and the mangling does differ
between gfortran, iFort etc. */
const char *physname
= ((cu->lang () == language_fortran || cu->lang () == language_ada)
? dwarf2_full_name (name, die, cu)
: dwarf2_physname (name, die, cu));
const char *linkagename = dw2_linkage_name (die, cu);
if (linkagename == nullptr)
sym->set_linkage_name (physname);
else if (cu->lang () == language_ada)
sym->set_linkage_name (linkagename);
else
{
if (physname == linkagename)
sym->set_demangled_name (name, &objfile->objfile_obstack);
else
sym->set_demangled_name (physname, &objfile->objfile_obstack);
sym->set_linkage_name (linkagename);
}
/* Handle DW_AT_artificial. */
attr = dwarf2_attr (die, DW_AT_artificial, cu);
if (attr != nullptr)
sym->set_is_artificial (attr->as_boolean ());
/* Default assumptions.
Use the passed type or decode it from the die. */
sym->set_domain (UNDEF_DOMAIN);
sym->set_aclass_index (LOC_OPTIMIZED_OUT);
if (type != NULL)
sym->set_type (type);
else
sym->set_type (die_type (die, cu));
attr = dwarf2_attr (die,
inlined_func ? DW_AT_call_line : DW_AT_decl_line,
cu);
if (attr != nullptr)
sym->set_line (attr->unsigned_constant ().value_or (0));
struct dwarf2_cu *file_cu = cu;
attr = dwarf2_attr (die,
inlined_func ? DW_AT_call_file : DW_AT_decl_file,
&file_cu);
if (attr != nullptr)
{
std::optional<ULONGEST> index_cst = attr->unsigned_constant ();
if (index_cst.has_value ())
{
file_name_index file_index = (file_name_index) *index_cst;
struct file_entry *fe;
if (file_cu->line_header == nullptr)
{
file_and_directory fnd (nullptr, nullptr);
handle_DW_AT_stmt_list (file_cu->dies, file_cu, fnd, {}, false);
}
if (file_cu->line_header != nullptr)
fe = file_cu->line_header->file_name_at (file_index);
else
fe = NULL;
if (fe == NULL)
complaint (_("file index out of range"));
else
sym->set_symtab (fe->symtab);
}
}
switch (die->tag)
{
case DW_TAG_label:
attr = dwarf2_attr (die, DW_AT_low_pc, cu);
if (attr != nullptr)
{
CORE_ADDR addr = per_objfile->relocate (attr->as_address ());
sym->set_section_index (SECT_OFF_TEXT (objfile));
sym->set_value_address (addr);
sym->set_aclass_index (LOC_LABEL);
}
else
sym->set_aclass_index (LOC_OPTIMIZED_OUT);
sym->set_type (builtin_type (objfile)->builtin_core_addr);
sym->set_domain (LABEL_DOMAIN);
list_to_add = cu->list_in_scope;
break;
case DW_TAG_entry_point:
/* SYMBOL_BLOCK_VALUE (sym) will be filled in later by
finish_block. */
sym->set_domain (FUNCTION_DOMAIN);
sym->set_aclass_index (LOC_BLOCK);
/* DW_TAG_entry_point provides an additional entry_point to an
existing sub_program. Therefore, we inherit the "external"
attribute from the sub_program to which the entry_point
belongs to. */
attr2 = dwarf2_attr (die->parent, DW_AT_external, cu);
if (attr2 != nullptr && attr2->as_boolean ())
list_to_add = cu->get_builder ()->get_global_symbols ();
else
list_to_add = cu->list_in_scope;
break;
case DW_TAG_subprogram:
/* SYMBOL_BLOCK_VALUE (sym) will be filled in later by
finish_block. */
sym->set_domain (FUNCTION_DOMAIN);
sym->set_aclass_index (LOC_BLOCK);
attr2 = dwarf2_attr (die, DW_AT_external, cu);
if ((attr2 != nullptr && attr2->as_boolean ())
|| cu->lang () == language_ada
|| cu->lang () == language_fortran)
{
/* Subprograms marked external are stored as a global symbol.
Ada and Fortran subprograms, whether marked external or
not, are always stored as a global symbol, because we want
to be able to access them globally. For instance, we want
to be able to break on a nested subprogram without having
to specify the context. */
list_to_add = cu->get_builder ()->get_global_symbols ();
}
else
{
list_to_add = cu->list_in_scope;
}
if (is_ada_import_or_export (cu, physname, linkagename))
{
/* This is either a Pragma Import or Export. They can
be distinguished by the declaration flag. */
sym->set_linkage_name (physname);
if (die_is_declaration (die, cu))
{
/* For Import, create a symbol using the source
name, and have it refer to the linkage name. */
SYMBOL_LOCATION_BATON (sym) = (void *) linkagename;
sym->set_aclass_index (ada_block_index);
}
else
{
/* For Export, create a symbol using the source
name, then create a second symbol that refers
back to it. */
add_ada_export_symbol (sym, linkagename, physname, cu,
list_to_add);
}
}
break;
case DW_TAG_inlined_subroutine:
/* SYMBOL_BLOCK_VALUE (sym) will be filled in later by
finish_block. */
sym->set_domain (FUNCTION_DOMAIN);
sym->set_aclass_index (LOC_BLOCK);
sym->set_is_inlined (1);
list_to_add = cu->list_in_scope;
break;
case DW_TAG_template_value_param:
suppress_add = 1;
[[fallthrough]];
case DW_TAG_constant:
case DW_TAG_variable:
case DW_TAG_member:
sym->set_domain (VAR_DOMAIN);
/* Compilation with minimal debug info may result in
variables with missing type entries. Change the
misleading `void' type to something sensible. */
if (sym->type ()->code () == TYPE_CODE_VOID)
sym->set_type (builtin_type (objfile)->builtin_int);
attr = dwarf2_attr (die, DW_AT_const_value, cu);
/* In the case of DW_TAG_member, we should only be called for
static const members. */
if (die->tag == DW_TAG_member)
{
/* dwarf2_add_field uses die_is_declaration,
so we do the same. */
gdb_assert (die_is_declaration (die, cu));
gdb_assert (attr);
}
if (attr != nullptr)
{
dwarf2_const_value (attr, sym, cu);
attr2 = dwarf2_attr (die, DW_AT_external, cu);
if (!suppress_add)
{
if (attr2 != nullptr && attr2->as_boolean ())
list_to_add = cu->get_builder ()->get_global_symbols ();
else
list_to_add = cu->list_in_scope;
}
break;
}
attr = dwarf2_attr (die, DW_AT_location, cu);
if (attr != nullptr)
{
var_decode_location (attr, sym, cu);
attr2 = dwarf2_attr (die, DW_AT_external, cu);
/* Fortran explicitly imports any global symbols to the local
scope by DW_TAG_common_block. */
if (cu->lang () == language_fortran && die->parent
&& die->parent->tag == DW_TAG_common_block)
attr2 = NULL;
if (sym->aclass () == LOC_STATIC
&& sym->value_address () == 0
&& !per_objfile->per_bfd->has_section_at_zero)
{
/* When a static variable is eliminated by the linker,
the corresponding debug information is not stripped
out, but the variable address is set to null;
do not add such variables into symbol table. */
}
else if (attr2 != nullptr && attr2->as_boolean ())
{
if (sym->aclass () == LOC_STATIC
&& (objfile->flags & OBJF_MAINLINE) == 0
&& per_objfile->per_bfd->can_copy)
{
/* A global static variable might be subject to
copy relocation. We first check for a local
minsym, though, because maybe the symbol was
marked hidden, in which case this would not
apply. */
bound_minimal_symbol found
= (lookup_minimal_symbol_linkage
(sym->linkage_name (), objfile, false));
if (found.minsym != nullptr)
sym->maybe_copied = 1;
}
/* A variable with DW_AT_external is never static,
but it may be block-scoped. */
list_to_add
= ((cu->list_in_scope
== cu->get_builder ()->get_file_symbols ())
? cu->get_builder ()->get_global_symbols ()
: cu->list_in_scope);
}
else
list_to_add = cu->list_in_scope;
if (list_to_add != nullptr
&& is_ada_import_or_export (cu, physname, linkagename))
{
/* This is a Pragma Export. A Pragma Import won't
be seen here, because it will not have a location
and so will be handled below. */
add_ada_export_symbol (sym, physname, linkagename, cu,
list_to_add);
}
}
else
{
/* We do not know the address of this symbol.
If it is an external symbol and we have type information
for it, enter the symbol as a LOC_UNRESOLVED symbol.
The address of the variable will then be determined from
the minimal symbol table whenever the variable is
referenced. */
attr2 = dwarf2_attr (die, DW_AT_external, cu);
/* Fortran explicitly imports any global symbols to the local
scope by DW_TAG_common_block. */
if (cu->lang () == language_fortran && die->parent
&& die->parent->tag == DW_TAG_common_block)
{
/* SYMBOL_CLASS doesn't matter here because
read_common_block is going to reset it. */
if (!suppress_add)
list_to_add = cu->list_in_scope;
}
else if (is_ada_import_or_export (cu, physname, linkagename))
{
/* This is a Pragma Import. A Pragma Export won't
be seen here, because it will have a location and
so will be handled above. */
sym->set_linkage_name (physname);
list_to_add
= ((cu->list_in_scope
== cu->get_builder ()->get_file_symbols ())
? cu->get_builder ()->get_global_symbols ()
: cu->list_in_scope);
SYMBOL_LOCATION_BATON (sym) = (void *) linkagename;
sym->set_aclass_index (ada_imported_index);
}
else if (attr2 != nullptr && attr2->as_boolean ()
&& dwarf2_attr (die, DW_AT_type, cu) != NULL)
{
/* A variable with DW_AT_external is never static, but it
may be block-scoped. */
list_to_add
= ((cu->list_in_scope
== cu->get_builder ()->get_file_symbols ())
? cu->get_builder ()->get_global_symbols ()
: cu->list_in_scope);
sym->set_aclass_index (LOC_UNRESOLVED);
}
else if (!die_is_declaration (die, cu))
{
/* Use the default LOC_OPTIMIZED_OUT class. */
gdb_assert (sym->aclass () == LOC_OPTIMIZED_OUT);
if (!suppress_add)
list_to_add = cu->list_in_scope;
}
}
break;
case DW_TAG_formal_parameter:
{
/* If we are inside a function, mark this as an argument. If
not, we might be looking at an argument to an inlined function
when we do not have enough information to show inlined frames;
pretend it's a local variable in that case so that the user can
still see it. */
sym->set_domain (VAR_DOMAIN);
struct context_stack *curr
= cu->get_builder ()->get_current_context_stack ();
if (curr != nullptr && curr->name != nullptr)
sym->set_is_argument (1);
attr = dwarf2_attr (die, DW_AT_location, cu);
if (attr != nullptr)
{
var_decode_location (attr, sym, cu);
}
attr = dwarf2_attr (die, DW_AT_const_value, cu);
if (attr != nullptr)
{
dwarf2_const_value (attr, sym, cu);
}
list_to_add = cu->list_in_scope;
}
break;
case DW_TAG_unspecified_parameters:
/* From varargs functions; gdb doesn't seem to have any
interest in this information, so just ignore it for now.
(FIXME?) */
break;
case DW_TAG_template_type_param:
suppress_add = 1;
[[fallthrough]];
case DW_TAG_class_type:
case DW_TAG_interface_type:
case DW_TAG_structure_type:
case DW_TAG_union_type:
case DW_TAG_set_type:
case DW_TAG_enumeration_type:
if (cu->lang () == language_c
|| cu->lang () == language_cplus
|| cu->lang () == language_objc
|| cu->lang () == language_opencl
|| cu->lang () == language_minimal)
{
/* These languages have a tag namespace. Note that
there's a special hack for C++ in the matching code,
so we don't need to enter a separate typedef for the
tag. */
sym->set_aclass_index (LOC_TYPEDEF);
sym->set_domain (STRUCT_DOMAIN);
}
else
{
/* Other languages don't have a tag namespace. */
sym->set_aclass_index (LOC_TYPEDEF);
sym->set_domain (TYPE_DOMAIN);
}
/* NOTE: carlton/2003-11-10: C++ class symbols shouldn't
really ever be static objects: otherwise, if you try
to, say, break of a class's method and you're in a file
which doesn't mention that class, it won't work unless
the check for all static symbols in lookup_symbol_aux
saves you. See the OtherFileClass tests in
gdb.c++/namespace.exp. */
if (!suppress_add)
{
buildsym_compunit *builder = cu->get_builder ();
list_to_add
= (cu->list_in_scope == builder->get_file_symbols ()
&& cu->lang () == language_cplus
? builder->get_global_symbols ()
: cu->list_in_scope);
/* The semantics of C++ state that "struct foo {
... }" also defines a typedef for "foo". */
if (cu->lang () == language_cplus
|| cu->lang () == language_ada
|| cu->lang () == language_d
|| cu->lang () == language_rust)
{
/* The symbol's name is already allocated along
with this objfile, so we don't need to
duplicate it for the type. */
if (sym->type ()->name () == 0)
sym->type ()->set_name (sym->search_name ());
}
}
break;
case DW_TAG_unspecified_type:
if (cu->lang () == language_ada)
break;
[[fallthrough]];
case DW_TAG_typedef:
case DW_TAG_array_type:
case DW_TAG_base_type:
case DW_TAG_subrange_type:
case DW_TAG_generic_subrange:
sym->set_aclass_index (LOC_TYPEDEF);
sym->set_domain (TYPE_DOMAIN);
list_to_add = cu->list_in_scope;
break;
case DW_TAG_enumerator:
sym->set_domain (VAR_DOMAIN);
attr = dwarf2_attr (die, DW_AT_const_value, cu);
if (attr != nullptr)
{
dwarf2_const_value (attr, sym, cu);
}
/* NOTE: carlton/2003-11-10: See comment above in the
DW_TAG_class_type, etc. block. */
list_to_add
= (cu->list_in_scope == cu->get_builder ()->get_file_symbols ()
&& cu->lang () == language_cplus
? cu->get_builder ()->get_global_symbols ()
: cu->list_in_scope);
break;
case DW_TAG_imported_declaration:
case DW_TAG_namespace:
sym->set_domain (TYPE_DOMAIN);
sym->set_aclass_index (LOC_TYPEDEF);
list_to_add = cu->get_builder ()->get_global_symbols ();
break;
case DW_TAG_module:
sym->set_aclass_index (LOC_TYPEDEF);
sym->set_domain (MODULE_DOMAIN);
list_to_add = cu->get_builder ()->get_global_symbols ();
break;
case DW_TAG_common_block:
sym->set_aclass_index (LOC_COMMON_BLOCK);
sym->set_domain (COMMON_BLOCK_DOMAIN);
list_to_add = cu->list_in_scope;
break;
case DW_TAG_namelist:
sym->set_aclass_index (LOC_STATIC);
sym->set_domain (VAR_DOMAIN);
list_to_add = cu->list_in_scope;
break;
default:
/* Not a tag we recognize. Hopefully we aren't processing
trash data, but since we must specifically ignore things
we don't recognize, there is nothing else we should do at
this point. */
complaint (_("unsupported tag: '%s'"),
dwarf_tag_name (die->tag));
break;
}
if (suppress_add)
{
sym->hash_next = objfile->template_symbols;
objfile->template_symbols = sym;
list_to_add = NULL;
}
if (list_to_add != NULL)
add_symbol_to_list (sym, list_to_add);
/* For the benefit of old versions of GCC, check for anonymous
namespaces based on the demangled name. */
if (!cu->processing_has_namespace_info
&& cu->lang () == language_cplus)
cp_scan_for_anonymous_namespaces (cu->get_builder (), sym, objfile);
}
return (sym);
}
/* Given an attr with a DW_FORM_dataN value in host byte order,
zero-extend it as appropriate for the symbol's type. The DWARF
standard (v4) is not entirely clear about the meaning of using
DW_FORM_dataN for a constant with a signed type, where the type is
wider than the data. The conclusion of a discussion on the DWARF
list was that this is unspecified. We choose to always zero-extend
because that is the interpretation long in use by GCC. */
static gdb_byte *
dwarf2_const_value_data (const struct attribute *attr, struct obstack *obstack,
struct dwarf2_cu *cu, LONGEST *value, int bits)
{
struct objfile *objfile = cu->per_objfile->objfile;
enum bfd_endian byte_order = bfd_big_endian (objfile->obfd.get ()) ?
BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE;
LONGEST l = attr->constant_value (0);
if (bits < sizeof (*value) * 8)
{
l &= ((LONGEST) 1 << bits) - 1;
*value = l;
}
else if (bits == sizeof (*value) * 8)
*value = l;
else
{
gdb_byte *bytes = (gdb_byte *) obstack_alloc (obstack, bits / 8);
store_unsigned_integer (bytes, bits / 8, byte_order, l);
return bytes;
}
return NULL;
}
/* Read a constant value from an attribute. Either set *VALUE, or if
the value does not fit in *VALUE, set *BYTES - either already
allocated on the objfile obstack, or newly allocated on OBSTACK,
or, set *BATON, if we translated the constant to a location
expression. */
static void
dwarf2_const_value_attr (const struct attribute *attr, struct type *type,
const char *name, struct obstack *obstack,
struct dwarf2_cu *cu,
LONGEST *value, const gdb_byte **bytes,
struct dwarf2_locexpr_baton **baton)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct comp_unit_head *cu_header = &cu->header;
struct dwarf_block *blk;
enum bfd_endian byte_order = (bfd_big_endian (objfile->obfd.get ()) ?
BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE);
*value = 0;
*bytes = NULL;
*baton = NULL;
switch (attr->form)
{
case DW_FORM_addr:
case DW_FORM_addrx:
case DW_FORM_GNU_addr_index:
{
gdb_byte *data;
if (type->length () != cu_header->addr_size)
dwarf2_const_value_length_mismatch_complaint (name,
cu_header->addr_size,
type->length ());
/* Symbols of this form are reasonably rare, so we just
piggyback on the existing location code rather than writing
a new implementation of symbol_computed_ops. */
*baton = XOBNEW (obstack, struct dwarf2_locexpr_baton);
(*baton)->per_objfile = per_objfile;
(*baton)->per_cu = cu->per_cu;
gdb_assert ((*baton)->per_cu);
(*baton)->size = 2 + cu_header->addr_size;
data = (gdb_byte *) obstack_alloc (obstack, (*baton)->size);
(*baton)->data = data;
data[0] = DW_OP_addr;
store_unsigned_integer (&data[1], cu_header->addr_size,
byte_order, (ULONGEST) attr->as_address ());
data[cu_header->addr_size + 1] = DW_OP_stack_value;
}
break;
case DW_FORM_string:
case DW_FORM_strp:
case DW_FORM_strx:
case DW_FORM_GNU_str_index:
case DW_FORM_GNU_strp_alt:
/* The string is already allocated on the objfile obstack, point
directly to it. */
*bytes = (const gdb_byte *) attr->as_string ();
break;
case DW_FORM_block1:
case DW_FORM_block2:
case DW_FORM_block4:
case DW_FORM_block:
case DW_FORM_exprloc:
case DW_FORM_data16:
blk = attr->as_block ();
if (type->length () != blk->size)
dwarf2_const_value_length_mismatch_complaint (name, blk->size,
type->length ());
*bytes = blk->data;
break;
/* The DW_AT_const_value attributes are supposed to carry the
symbol's value "represented as it would be on the target
architecture." By the time we get here, it's already been
converted to host endianness, so we just need to sign- or
zero-extend it as appropriate. */
case DW_FORM_data1:
*bytes = dwarf2_const_value_data (attr, obstack, cu, value, 8);
break;
case DW_FORM_data2:
*bytes = dwarf2_const_value_data (attr, obstack, cu, value, 16);
break;
case DW_FORM_data4:
*bytes = dwarf2_const_value_data (attr, obstack, cu, value, 32);
break;
case DW_FORM_data8:
*bytes = dwarf2_const_value_data (attr, obstack, cu, value, 64);
break;
case DW_FORM_sdata:
case DW_FORM_implicit_const:
*value = attr->as_signed ();
break;
case DW_FORM_udata:
*value = attr->as_unsigned ();
break;
default:
complaint (_("unsupported const value attribute form: '%s'"),
dwarf_form_name (attr->form));
*value = 0;
break;
}
}
/* Copy constant value from an attribute to a symbol. */
static void
dwarf2_const_value (const struct attribute *attr, struct symbol *sym,
struct dwarf2_cu *cu)
{
struct objfile *objfile = cu->per_objfile->objfile;
LONGEST value;
const gdb_byte *bytes;
struct dwarf2_locexpr_baton *baton;
dwarf2_const_value_attr (attr, sym->type (),
sym->print_name (),
&objfile->objfile_obstack, cu,
&value, &bytes, &baton);
if (baton != NULL)
{
SYMBOL_LOCATION_BATON (sym) = baton;
sym->set_aclass_index (dwarf2_locexpr_index);
}
else if (bytes != NULL)
{
sym->set_value_bytes (bytes);
sym->set_aclass_index (LOC_CONST_BYTES);
}
else
{
sym->set_value_longest (value);
sym->set_aclass_index (LOC_CONST);
}
}
/* Return the type of the die in question using its DW_AT_type attribute. */
static struct type *
die_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *type_attr;
type_attr = dwarf2_attr (die, DW_AT_type, cu);
if (!type_attr)
{
struct objfile *objfile = cu->per_objfile->objfile;
/* A missing DW_AT_type represents a void type. */
return builtin_type (objfile)->builtin_void;
}
return lookup_die_type (die, type_attr, cu);
}
/* True iff CU's producer generates GNAT Ada auxiliary information
that allows to find parallel types through that information instead
of having to do expensive parallel lookups by type name. */
static int
need_gnat_info (struct dwarf2_cu *cu)
{
/* Assume that the Ada compiler was GNAT, which always produces
the auxiliary information. */
return (cu->lang () == language_ada);
}
/* Return the auxiliary type of the die in question using its
DW_AT_GNAT_descriptive_type attribute. Returns NULL if the
attribute is not present. */
static struct type *
die_descriptive_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *type_attr;
type_attr = dwarf2_attr (die, DW_AT_GNAT_descriptive_type, cu);
if (!type_attr)
return NULL;
return lookup_die_type (die, type_attr, cu);
}
/* If DIE has a descriptive_type attribute, then set the TYPE's
descriptive type accordingly. */
static void
set_descriptive_type (struct type *type, struct die_info *die,
struct dwarf2_cu *cu)
{
struct type *descriptive_type = die_descriptive_type (die, cu);
if (descriptive_type)
{
ALLOCATE_GNAT_AUX_TYPE (type);
TYPE_DESCRIPTIVE_TYPE (type) = descriptive_type;
}
}
/* Return the containing type of the die in question using its
DW_AT_containing_type attribute. */
static struct type *
die_containing_type (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *type_attr;
struct objfile *objfile = cu->per_objfile->objfile;
type_attr = dwarf2_attr (die, DW_AT_containing_type, cu);
if (!type_attr)
error (_(DWARF_ERROR_PREFIX
"Problem turning containing type into gdb type "
"[in module %s]"),
objfile_name (objfile));
return lookup_die_type (die, type_attr, cu);
}
/* Return an error marker type to use for the ill formed type in DIE/CU. */
static struct type *
build_error_marker_type (struct dwarf2_cu *cu, struct die_info *die)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
char *saved;
std::string message
= string_printf (_("<unknown type in %s, CU %s, DIE %s>"),
objfile_name (objfile),
sect_offset_str (cu->header.sect_off),
sect_offset_str (die->sect_off));
saved = obstack_strdup (&objfile->objfile_obstack, message);
return type_allocator (objfile, cu->lang ()).new_type (TYPE_CODE_ERROR,
0, saved);
}
/* Look up the type of DIE in CU using its type attribute ATTR.
ATTR must be one of: DW_AT_type, DW_AT_GNAT_descriptive_type,
DW_AT_containing_type.
If there is no type substitute an error marker. */
static struct type *
lookup_die_type (struct die_info *die, const struct attribute *attr,
struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct type *this_type;
gdb_assert (attr->name == DW_AT_type
|| attr->name == DW_AT_GNAT_descriptive_type
|| attr->name == DW_AT_containing_type);
/* First see if we have it cached. */
if (attr->form == DW_FORM_GNU_ref_alt)
{
sect_offset sect_off = attr->get_ref_die_offset ();
dwarf2_per_cu *per_cu
= dwarf2_find_containing_comp_unit (sect_off, 1, per_objfile->per_bfd);
this_type = get_die_type_at_offset (sect_off, per_cu, per_objfile);
}
else if (attr->form_is_ref ())
{
sect_offset sect_off = attr->get_ref_die_offset ();
this_type = get_die_type_at_offset (sect_off, cu->per_cu, per_objfile);
}
else if (attr->form == DW_FORM_ref_sig8)
{
ULONGEST signature = attr->as_signature ();
return get_signatured_type (die, signature, cu);
}
else
{
complaint (_(DWARF_ERROR_PREFIX
"Bad type attribute %s in DIE at %s [in module %s]"),
dwarf_attr_name (attr->name), sect_offset_str (die->sect_off),
objfile_name (objfile));
return build_error_marker_type (cu, die);
}
/* If not cached we need to read it in. */
if (this_type == NULL)
{
struct die_info *type_die = NULL;
struct dwarf2_cu *type_cu = cu;
if (attr->form_is_ref ())
type_die = follow_die_ref (die, attr, &type_cu);
if (type_die == NULL)
return build_error_marker_type (cu, die);
/* If we find the type now, it's probably because the type came
from an inter-CU reference and the type's CU got expanded before
ours. */
this_type = read_type_die (type_die, type_cu);
}
/* If we still don't have a type use an error marker. */
if (this_type == NULL)
return build_error_marker_type (cu, die);
return this_type;
}
/* Return the type in DIE, CU.
Returns NULL for invalid types.
This first does a lookup in die_type_hash,
and only reads the die in if necessary.
NOTE: This can be called when reading in partial or full symbols. */
static struct type *
read_type_die (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *this_type;
this_type = get_die_type (die, cu);
if (this_type)
return this_type;
return read_type_die_1 (die, cu);
}
/* Read the type in DIE, CU.
Returns NULL for invalid types. */
static struct type *
read_type_die_1 (struct die_info *die, struct dwarf2_cu *cu)
{
struct type *this_type = NULL;
switch (die->tag)
{
case DW_TAG_class_type:
case DW_TAG_interface_type:
case DW_TAG_structure_type:
case DW_TAG_union_type:
this_type = read_structure_type (die, cu);
break;
case DW_TAG_enumeration_type:
this_type = read_enumeration_type (die, cu);
break;
case DW_TAG_entry_point:
case DW_TAG_subprogram:
case DW_TAG_subroutine_type:
case DW_TAG_inlined_subroutine:
this_type = read_subroutine_type (die, cu);
break;
case DW_TAG_array_type:
this_type = read_array_type (die, cu);
break;
case DW_TAG_set_type:
this_type = read_set_type (die, cu);
break;
case DW_TAG_pointer_type:
this_type = read_tag_pointer_type (die, cu);
break;
case DW_TAG_ptr_to_member_type:
this_type = read_tag_ptr_to_member_type (die, cu);
break;
case DW_TAG_reference_type:
this_type = read_tag_reference_type (die, cu, TYPE_CODE_REF);
break;
case DW_TAG_rvalue_reference_type:
this_type = read_tag_reference_type (die, cu, TYPE_CODE_RVALUE_REF);
break;
case DW_TAG_const_type:
this_type = read_tag_const_type (die, cu);
break;
case DW_TAG_volatile_type:
this_type = read_tag_volatile_type (die, cu);
break;
case DW_TAG_restrict_type:
this_type = read_tag_restrict_type (die, cu);
break;
case DW_TAG_string_type:
this_type = read_tag_string_type (die, cu);
break;
case DW_TAG_typedef:
this_type = read_typedef (die, cu);
break;
case DW_TAG_generic_subrange:
case DW_TAG_subrange_type:
this_type = read_subrange_type (die, cu);
break;
case DW_TAG_base_type:
this_type = read_base_type (die, cu);
break;
case DW_TAG_unspecified_type:
this_type = read_unspecified_type (die, cu);
break;
case DW_TAG_namespace:
this_type = read_namespace_type (die, cu);
break;
case DW_TAG_module:
this_type = read_module_type (die, cu);
break;
case DW_TAG_atomic_type:
this_type = read_tag_atomic_type (die, cu);
break;
default:
complaint (_("unexpected tag in read_type_die: '%s'"),
dwarf_tag_name (die->tag));
break;
}
return this_type;
}
/* See if we can figure out if the class lives in a namespace. We do
this by looking for a member function; its demangled name will
contain namespace info, if there is any.
Return the computed name or NULL.
Space for the result is allocated on the objfile's obstack.
This is the full-die version of guess_partial_die_structure_name.
In this case we know DIE has no useful parent. */
static const char *
guess_full_die_structure_name (struct die_info *die, struct dwarf2_cu *cu)
{
struct die_info *spec_die;
struct dwarf2_cu *spec_cu;
struct die_info *child;
struct objfile *objfile = cu->per_objfile->objfile;
spec_cu = cu;
spec_die = die_specification (die, &spec_cu);
if (spec_die != NULL)
{
die = spec_die;
cu = spec_cu;
}
for (child = die->child;
child != NULL;
child = child->sibling)
{
if (child->tag == DW_TAG_subprogram)
{
const char *linkage_name = dw2_linkage_name (child, cu);
if (linkage_name != NULL)
{
gdb::unique_xmalloc_ptr<char> actual_name
(cu->language_defn->class_name_from_physname (linkage_name));
const char *name = NULL;
if (actual_name != NULL)
{
const char *die_name = dwarf2_name (die, cu);
if (die_name != NULL
&& strcmp (die_name, actual_name.get ()) != 0)
{
/* Strip off the class name from the full name.
We want the prefix. */
int die_name_len = strlen (die_name);
int actual_name_len = strlen (actual_name.get ());
const char *ptr = actual_name.get ();
/* Test for '::' as a sanity check. */
if (actual_name_len > die_name_len + 2
&& ptr[actual_name_len - die_name_len - 1] == ':')
name = obstack_strndup (
&objfile->per_bfd->storage_obstack,
ptr, actual_name_len - die_name_len - 2);
}
}
return name;
}
}
}
return NULL;
}
/* GCC might emit a nameless typedef that has a linkage name. Determine the
prefix part in such case. See
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47510. */
static const char *
anonymous_struct_prefix (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr;
const char *base;
if (die->tag != DW_TAG_class_type && die->tag != DW_TAG_interface_type
&& die->tag != DW_TAG_structure_type && die->tag != DW_TAG_union_type)
return NULL;
if (dwarf2_string_attr (die, DW_AT_name, cu) != NULL)
return NULL;
attr = dw2_linkage_name_attr (die, cu);
const char *attr_name = attr->as_string ();
if (attr == NULL || attr_name == NULL)
return NULL;
/* dwarf2_name had to be already called. */
gdb_assert (attr->canonical_string_p ());
/* Strip the base name, keep any leading namespaces/classes. */
base = strrchr (attr_name, ':');
if (base == NULL || base == attr_name || base[-1] != ':')
return "";
struct objfile *objfile = cu->per_objfile->objfile;
return obstack_strndup (&objfile->per_bfd->storage_obstack,
attr_name,
&base[-1] - attr_name);
}
/* Return the name of the namespace/class that DIE is defined within,
or "" if we can't tell. The caller should not xfree the result.
For example, if we're within the method foo() in the following
code:
namespace N {
class C {
void foo () {
}
};
}
then determine_prefix on foo's die will return "N::C". */
static const char *
determine_prefix (struct die_info *die, struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct die_info *parent, *spec_die;
struct dwarf2_cu *spec_cu;
struct type *parent_type;
const char *retval;
if (cu->lang () != language_cplus
&& cu->lang () != language_fortran
&& cu->lang () != language_d
&& cu->lang () != language_rust
&& cu->lang () != language_ada)
return "";
retval = anonymous_struct_prefix (die, cu);
if (retval)
return retval;
/* We have to be careful in the presence of DW_AT_specification.
For example, with GCC 3.4, given the code
namespace N {
void foo() {
// Definition of N::foo.
}
}
then we'll have a tree of DIEs like this:
1: DW_TAG_compile_unit
2: DW_TAG_namespace // N
3: DW_TAG_subprogram // declaration of N::foo
4: DW_TAG_subprogram // definition of N::foo
DW_AT_specification // refers to die #3
Thus, when processing die #4, we have to pretend that we're in
the context of its DW_AT_specification, namely the context of die
#3. */
spec_cu = cu;
spec_die = die_specification (die, &spec_cu);
if (spec_die == NULL)
parent = die->parent;
else
{
parent = spec_die->parent;
cu = spec_cu;
}
if (parent == NULL)
return "";
else if (parent->building_fullname)
{
const char *name;
const char *parent_name;
/* It has been seen on RealView 2.2 built binaries,
DW_TAG_template_type_param types actually _defined_ as
children of the parent class:
enum E {};
template class <class Enum> Class{};
Class<enum E> class_e;
1: DW_TAG_class_type (Class)
2: DW_TAG_enumeration_type (E)
3: DW_TAG_enumerator (enum1:0)
3: DW_TAG_enumerator (enum2:1)
...
2: DW_TAG_template_type_param
DW_AT_type DW_FORM_ref_udata (E)
Besides being broken debug info, it can put GDB into an
infinite loop. Consider:
When we're building the full name for Class<E>, we'll start
at Class, and go look over its template type parameters,
finding E. We'll then try to build the full name of E, and
reach here. We're now trying to build the full name of E,
and look over the parent DIE for containing scope. In the
broken case, if we followed the parent DIE of E, we'd again
find Class, and once again go look at its template type
arguments, etc., etc. Simply don't consider such parent die
as source-level parent of this die (it can't be, the language
doesn't allow it), and break the loop here. */
name = dwarf2_name (die, cu);
parent_name = dwarf2_name (parent, cu);
complaint (_("template param type '%s' defined within parent '%s'"),
name ? name : "<unknown>",
parent_name ? parent_name : "<unknown>");
return "";
}
else
switch (parent->tag)
{
case DW_TAG_namespace:
parent_type = read_type_die (parent, cu);
/* GCC 4.0 and 4.1 had a bug (PR c++/28460) where they generated bogus
DW_TAG_namespace DIEs with a name of "::" for the global namespace.
Work around this problem here. */
if (cu->lang () == language_cplus
&& strcmp (parent_type->name (), "::") == 0)
return "";
/* We give a name to even anonymous namespaces. */
return parent_type->name ();
case DW_TAG_class_type:
case DW_TAG_interface_type:
case DW_TAG_structure_type:
case DW_TAG_union_type:
case DW_TAG_module:
parent_type = read_type_die (parent, cu);
if (parent_type->name () != NULL)
return parent_type->name ();
else
/* An anonymous structure is only allowed non-static data
members; no typedefs, no member functions, et cetera.
So it does not need a prefix. */
return "";
case DW_TAG_compile_unit:
case DW_TAG_partial_unit:
/* gcc-4.5 -gdwarf-4 can drop the enclosing namespace. Cope. */
if (cu->lang () == language_cplus
&& !per_objfile->per_bfd->types.empty ()
&& die->child != NULL
&& (die->tag == DW_TAG_class_type
|| die->tag == DW_TAG_structure_type
|| die->tag == DW_TAG_union_type))
{
const char *name = guess_full_die_structure_name (die, cu);
if (name != NULL)
return name;
}
return "";
case DW_TAG_subprogram:
/* Nested subroutines in Fortran get a prefix with the name
of the parent's subroutine. Entry points are prefixed by the
parent's namespace. */
if (cu->lang () == language_fortran)
{
if ((die->tag == DW_TAG_subprogram)
&& (dwarf2_name (parent, cu) != NULL))
return dwarf2_name (parent, cu);
else if (die->tag == DW_TAG_entry_point)
return determine_prefix (parent, cu);
}
else if (cu->lang () == language_ada
&& (die->tag == DW_TAG_subprogram
|| die->tag == DW_TAG_inlined_subroutine
|| die->tag == DW_TAG_lexical_block))
return dwarf2_full_name (nullptr, parent, cu);
return "";
case DW_TAG_enumeration_type:
parent_type = read_type_die (parent, cu);
if (parent_type->is_declared_class ())
{
if (parent_type->name () != NULL)
return parent_type->name ();
return "";
}
[[fallthrough]];
default:
return determine_prefix (parent, cu);
}
}
/* Return a newly-allocated string formed by concatenating PREFIX and
SUFFIX with appropriate separator. If PREFIX or SUFFIX is NULL or
empty, then simply copy the SUFFIX or PREFIX, respectively. The CU
argument is used to determine the language and hence, the
appropriate separator. */
static gdb::unique_xmalloc_ptr<char>
typename_concat (const char *prefix, const char *suffix, int physname,
struct dwarf2_cu *cu)
{
const char *lead = "";
const char *sep;
if (suffix == NULL || suffix[0] == '\0'
|| prefix == NULL || prefix[0] == '\0')
sep = "";
else if (cu->lang () == language_d)
{
/* For D, the 'main' function could be defined in any module, but it
should never be prefixed. */
if (strcmp (suffix, "D main") == 0)
{
prefix = "";
sep = "";
}
else
sep = ".";
}
else if (cu->lang () == language_fortran && physname)
{
/* This is gfortran specific mangling. Normally DW_AT_linkage_name or
DW_AT_MIPS_linkage_name is preferred and used instead. */
lead = "__";
sep = "_MOD_";
}
else if (cu->lang () == language_ada)
sep = "__";
else
sep = "::";
if (prefix == NULL)
prefix = "";
if (suffix == NULL)
suffix = "";
return gdb::unique_xmalloc_ptr<char> (concat (lead, prefix, sep, suffix,
nullptr));
}
/* Return a generic name for a DW_TAG_template_type_param or
DW_TAG_template_value_param tag, missing a DW_AT_name attribute. We do this
per parent, so each function/class/struct template will have their own set
of template parameters named <unnnamed0>, <unnamed1>, ... where the
enumeration starts at 0 and represents the position of the template tag in
the list of unnamed template tags for this parent, counting both, type and
value tags. */
static const char *
unnamed_template_tag_name (die_info *die, dwarf2_cu *cu)
{
if (die->parent == nullptr)
return nullptr;
/* Count the parent types unnamed template type and value children until, we
arrive at our entry. */
size_t nth_unnamed = 0;
die_info *child = die->parent->child;
while (child != die)
{
gdb_assert (child != nullptr);
if (child->tag == DW_TAG_template_type_param
|| child->tag == DW_TAG_template_value_param)
{
if (dwarf2_attr (child, DW_AT_name, cu) == nullptr)
++nth_unnamed;
}
child = child->sibling;
}
const std::string name_str = "<unnamed" + std::to_string (nth_unnamed) + ">";
return cu->per_objfile->objfile->intern (name_str.c_str ());
}
/* Get name of a die, return NULL if not found. */
static const char *
dwarf2_canonicalize_name (const char *name, struct dwarf2_cu *cu,
struct objfile *objfile)
{
if (name == nullptr)
return name;
if (cu->lang () == language_cplus)
{
gdb::unique_xmalloc_ptr<char> canon_name
= cp_canonicalize_string (name);
if (canon_name != nullptr)
name = objfile->intern (canon_name.get ());
}
else if (cu->lang () == language_c)
{
gdb::unique_xmalloc_ptr<char> canon_name
= c_canonicalize_name (name);
if (canon_name != nullptr)
name = objfile->intern (canon_name.get ());
}
return name;
}
/* Get name of a die, return NULL if not found.
Anonymous namespaces are converted to their magic string. */
static const char *
dwarf2_name (struct die_info *die, struct dwarf2_cu *cu)
{
struct attribute *attr;
struct objfile *objfile = cu->per_objfile->objfile;
attr = dwarf2_attr (die, DW_AT_name, cu);
const char *attr_name = attr == nullptr ? nullptr : attr->as_string ();
if (attr_name == nullptr
&& die->tag != DW_TAG_namespace
&& die->tag != DW_TAG_class_type
&& die->tag != DW_TAG_interface_type
&& die->tag != DW_TAG_structure_type
&& die->tag != DW_TAG_namelist
&& die->tag != DW_TAG_union_type
&& die->tag != DW_TAG_template_type_param
&& die->tag != DW_TAG_template_value_param
&& die->tag != DW_TAG_module)
return NULL;
switch (die->tag)
{
/* A member's name should not be canonicalized. This is a bit
of a hack, in that normally it should not be possible to run
into this situation; however, the dw2-unusual-field-names.exp
test creates custom DWARF that does. */
case DW_TAG_member:
case DW_TAG_compile_unit:
case DW_TAG_partial_unit:
/* Compilation units have a DW_AT_name that is a filename, not
a source language identifier. */
case DW_TAG_enumeration_type:
case DW_TAG_enumerator:
/* These tags always have simple identifiers already; no need
to canonicalize them. */
return attr_name;
case DW_TAG_namespace:
if (attr_name != nullptr)
return attr_name;
return CP_ANONYMOUS_NAMESPACE_STR;
/* DWARF does not actually require template tags to have a name. */
case DW_TAG_template_type_param:
case DW_TAG_template_value_param:
if (attr_name == nullptr)
return unnamed_template_tag_name (die, cu);
[[fallthrough]];
case DW_TAG_class_type:
case DW_TAG_interface_type:
case DW_TAG_structure_type:
case DW_TAG_union_type:
case DW_TAG_namelist:
/* Some GCC versions emit spurious DW_AT_name attributes for unnamed
structures or unions. These were of the form "._%d" in GCC 4.1,
or simply "<anonymous struct>" or "<anonymous union>" in GCC 4.3
and GCC 4.4. We work around this problem by ignoring these. */
if (attr_name != nullptr
&& (startswith (attr_name, "._")
|| startswith (attr_name, "<anonymous")))
return NULL;
/* GCC might emit a nameless typedef that has a linkage name. See
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47510. */
if (!attr || attr_name == NULL)
{
attr = dw2_linkage_name_attr (die, cu);
attr_name = attr == nullptr ? nullptr : attr->as_string ();
if (attr == NULL || attr_name == NULL)
return NULL;
/* Avoid demangling attr_name the second time on a second
call for the same DIE. */
if (!attr->canonical_string_p ())
{
gdb::unique_xmalloc_ptr<char> demangled
(gdb_demangle (attr_name, DMGL_TYPES));
if (demangled == nullptr)
return nullptr;
attr->set_string_canonical (objfile->intern (demangled.get ()));
attr_name = attr->as_string ();
}
/* Strip any leading namespaces/classes, keep only the
base name. DW_AT_name for named DIEs does not
contain the prefixes. */
const char *base = strrchr (attr_name, ':');
if (base && base > attr_name && base[-1] == ':')
return &base[1];
else
return attr_name;
}
break;
default:
break;
}
if (!attr->canonical_string_p ())
attr->set_string_canonical (dwarf2_canonicalize_name (attr_name, cu,
objfile));
return attr->as_string ();
}
/* Return the die that this die in an extension of, or NULL if there
is none. *EXT_CU is the CU containing DIE on input, and the CU
containing the return value on output. */
static struct die_info *
dwarf2_extension (struct die_info *die, struct dwarf2_cu **ext_cu)
{
struct attribute *attr;
attr = dwarf2_attr (die, DW_AT_extension, *ext_cu);
if (attr == NULL)
return NULL;
return follow_die_ref (die, attr, ext_cu);
}
/* Follow reference or signature attribute ATTR of SRC_DIE.
On entry *REF_CU is the CU of SRC_DIE.
On exit *REF_CU is the CU of the result. */
static struct die_info *
follow_die_ref_or_sig (struct die_info *src_die, const struct attribute *attr,
struct dwarf2_cu **ref_cu)
{
struct die_info *die;
if (attr->form_is_ref ())
die = follow_die_ref (src_die, attr, ref_cu);
else if (attr->form == DW_FORM_ref_sig8)
die = follow_die_sig (src_die, attr, ref_cu);
else
{
src_die->error_dump ();
error (_(DWARF_ERROR_PREFIX
"Expected reference attribute [in module %s]"),
objfile_name ((*ref_cu)->per_objfile->objfile));
}
return die;
}
/* Follow reference OFFSET.
On entry *REF_CU is the CU of the source die referencing OFFSET.
On exit *REF_CU is the CU of the result.
Returns NULL if OFFSET is invalid. */
static struct die_info *
follow_die_offset (sect_offset sect_off, int offset_in_dwz,
struct dwarf2_cu **ref_cu)
{
dwarf2_cu *source_cu = *ref_cu;
dwarf2_cu *target_cu = source_cu;
dwarf2_per_objfile *per_objfile = source_cu->per_objfile;
gdb_assert (source_cu->per_cu != nullptr);
gdb_assert (source_cu->dies != nullptr);
dwarf_read_debug_printf_v ("source CU offset: %s, target offset: %s, "
"source CU contains target offset: %d",
sect_offset_str (source_cu->per_cu->sect_off),
sect_offset_str (sect_off),
source_cu->header.offset_in_cu_p (sect_off));
if (source_cu->per_cu->is_debug_types)
{
/* .debug_types CUs cannot reference anything outside their CU.
If they need to, they have to reference a signatured type via
DW_FORM_ref_sig8. */
if (!source_cu->header.offset_in_cu_p (sect_off))
return NULL;
}
else if (offset_in_dwz != source_cu->per_cu->is_dwz
|| !source_cu->header.offset_in_cu_p (sect_off))
{
dwarf2_per_cu *target_per_cu
= dwarf2_find_containing_comp_unit (sect_off, offset_in_dwz,
per_objfile->per_bfd);
dwarf_read_debug_printf_v ("target CU offset: %s, "
"target CU DIEs loaded: %d",
sect_offset_str (target_per_cu->sect_off),
per_objfile->get_cu (target_per_cu) != nullptr);
/* If necessary, add it to the queue and load its DIEs.
Even if maybe_queue_comp_unit doesn't require us to load the CU's DIEs,
it doesn't mean they are currently loaded. Since we require them
to be loaded, we must check for ourselves. */
if (maybe_queue_comp_unit (source_cu, target_per_cu, per_objfile)
|| per_objfile->get_cu (target_per_cu) == nullptr)
load_full_comp_unit (target_per_cu, per_objfile, false,
source_cu->lang ());
target_cu = per_objfile->get_cu (target_per_cu);
if (target_cu == nullptr)
error (_(DWARF_ERROR_PREFIX
"cannot follow reference to DIE at %s"
" [in module %s]"),
sect_offset_str (sect_off),
objfile_name (per_objfile->objfile));
}
*ref_cu = target_cu;
auto it = target_cu->die_hash.find (sect_off);
return it != target_cu->die_hash.end () ? *it : nullptr;
}
/* Follow reference attribute ATTR of SRC_DIE.
On entry *REF_CU is the CU of SRC_DIE.
On exit *REF_CU is the CU of the result. */
static struct die_info *
follow_die_ref (struct die_info *src_die, const struct attribute *attr,
struct dwarf2_cu **ref_cu)
{
sect_offset sect_off = attr->get_ref_die_offset ();
struct dwarf2_cu *cu = *ref_cu;
struct die_info *die;
if (attr->form != DW_FORM_GNU_ref_alt && src_die->sect_off == sect_off)
{
/* Self-reference, we're done. */
return src_die;
}
die = follow_die_offset (sect_off,
(attr->form == DW_FORM_GNU_ref_alt
|| cu->per_cu->is_dwz),
ref_cu);
if (!die)
error (_(DWARF_ERROR_PREFIX
"Cannot find DIE at %s referenced from DIE at %s [in module %s]"),
sect_offset_str (sect_off), sect_offset_str (src_die->sect_off),
objfile_name (cu->per_objfile->objfile));
return die;
}
/* See read.h. */
struct dwarf2_locexpr_baton
dwarf2_fetch_die_loc_sect_off (sect_offset sect_off, dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile,
gdb::function_view<CORE_ADDR ()> get_frame_pc,
bool resolve_abstract_p)
{
struct die_info *die;
struct attribute *attr;
struct dwarf2_locexpr_baton retval;
struct objfile *objfile = per_objfile->objfile;
dwarf2_cu *cu = per_objfile->get_cu (per_cu);
if (cu == nullptr)
cu = load_cu (per_cu, per_objfile, false);
if (cu == nullptr)
{
/* We shouldn't get here for a dummy CU, but don't crash on the user.
Instead just throw an error, not much else we can do. */
error (_(DWARF_ERROR_PREFIX
"Dummy CU at %s referenced [in module %s]"),
sect_offset_str (sect_off), objfile_name (objfile));
}
die = follow_die_offset (sect_off, per_cu->is_dwz, &cu);
if (!die)
error (_(DWARF_ERROR_PREFIX
"Cannot find DIE at %s referenced [in module %s]"),
sect_offset_str (sect_off), objfile_name (objfile));
attr = dwarf2_attr (die, DW_AT_location, cu);
if (!attr && resolve_abstract_p
&& (per_objfile->per_bfd->abstract_to_concrete.find (die->sect_off)
!= per_objfile->per_bfd->abstract_to_concrete.end ()))
{
CORE_ADDR pc = get_frame_pc ();
for (const auto &cand_off
: per_objfile->per_bfd->abstract_to_concrete[die->sect_off])
{
struct dwarf2_cu *cand_cu = cu;
struct die_info *cand
= follow_die_offset (cand_off, per_cu->is_dwz, &cand_cu);
if (!cand
|| !cand->parent
|| cand->parent->tag != DW_TAG_subprogram)
continue;
unrelocated_addr unrel_low, unrel_high;
get_scope_pc_bounds (cand->parent, &unrel_low, &unrel_high, cu);
if (unrel_low == ((unrelocated_addr) -1))
continue;
CORE_ADDR pc_low = per_objfile->relocate (unrel_low);
CORE_ADDR pc_high = per_objfile->relocate (unrel_high);
if (!(pc_low <= pc && pc < pc_high))
continue;
die = cand;
attr = dwarf2_attr (die, DW_AT_location, cu);
break;
}
}
if (!attr)
{
/* DWARF: "If there is no such attribute, then there is no effect.".
DATA is ignored if SIZE is 0. */
retval.data = NULL;
retval.size = 0;
}
else if (attr->form_is_section_offset ())
{
struct dwarf2_loclist_baton loclist_baton;
CORE_ADDR pc = get_frame_pc ();
size_t size;
fill_in_loclist_baton (cu, &loclist_baton, attr);
retval.data = dwarf2_find_location_expression (&loclist_baton,
&size, pc);
retval.size = size;
}
else
{
if (!attr->form_is_block ())
error (_(DWARF_ERROR_PREFIX
"DIE at %s is neither DW_FORM_block* nor DW_FORM_exprloc"
" [in module %s]"),
sect_offset_str (sect_off), objfile_name (objfile));
struct dwarf_block *block = attr->as_block ();
retval.data = block->data;
retval.size = block->size;
}
retval.per_objfile = per_objfile;
retval.per_cu = cu->per_cu;
per_objfile->age_comp_units ();
return retval;
}
/* See read.h. */
struct dwarf2_locexpr_baton
dwarf2_fetch_die_loc_cu_off (cu_offset offset_in_cu, dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile,
gdb::function_view<CORE_ADDR ()> get_frame_pc)
{
sect_offset sect_off = per_cu->sect_off + to_underlying (offset_in_cu);
return dwarf2_fetch_die_loc_sect_off (sect_off, per_cu, per_objfile,
get_frame_pc);
}
/* Write a constant of a given type as target-ordered bytes into
OBSTACK. */
static const gdb_byte *
write_constant_as_bytes (struct obstack *obstack,
enum bfd_endian byte_order,
struct type *type,
ULONGEST value,
LONGEST *len)
{
gdb_byte *result;
*len = type->length ();
result = (gdb_byte *) obstack_alloc (obstack, *len);
store_unsigned_integer (result, *len, byte_order, value);
return result;
}
/* See read.h. */
const gdb_byte *
dwarf2_fetch_constant_bytes (sect_offset sect_off,
dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile,
obstack *obstack,
LONGEST *len)
{
struct die_info *die;
struct attribute *attr;
const gdb_byte *result = NULL;
struct type *type;
LONGEST value;
enum bfd_endian byte_order;
struct objfile *objfile = per_objfile->objfile;
dwarf2_cu *cu = per_objfile->get_cu (per_cu);
if (cu == nullptr)
cu = load_cu (per_cu, per_objfile, false);
if (cu == nullptr)
{
/* We shouldn't get here for a dummy CU, but don't crash on the user.
Instead just throw an error, not much else we can do. */
error (_(DWARF_ERROR_PREFIX
"Dummy CU at %s referenced [in module %s]"),
sect_offset_str (sect_off), objfile_name (objfile));
}
die = follow_die_offset (sect_off, per_cu->is_dwz, &cu);
if (!die)
error (_(DWARF_ERROR_PREFIX
"Cannot find DIE at %s referenced [in module %s]"),
sect_offset_str (sect_off), objfile_name (objfile));
attr = dwarf2_attr (die, DW_AT_const_value, cu);
if (attr == NULL)
return NULL;
byte_order = (bfd_big_endian (objfile->obfd.get ())
? BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE);
switch (attr->form)
{
case DW_FORM_addr:
case DW_FORM_addrx:
case DW_FORM_GNU_addr_index:
{
gdb_byte *tem;
*len = cu->header.addr_size;
tem = (gdb_byte *) obstack_alloc (obstack, *len);
store_unsigned_integer (tem, *len, byte_order,
(ULONGEST) attr->as_address ());
result = tem;
}
break;
case DW_FORM_string:
case DW_FORM_strp:
case DW_FORM_strx:
case DW_FORM_GNU_str_index:
case DW_FORM_GNU_strp_alt:
/* The string is already allocated on the objfile obstack, point
directly to it. */
{
const char *attr_name = attr->as_string ();
result = (const gdb_byte *) attr_name;
*len = strlen (attr_name);
}
break;
case DW_FORM_block1:
case DW_FORM_block2:
case DW_FORM_block4:
case DW_FORM_block:
case DW_FORM_exprloc:
case DW_FORM_data16:
{
struct dwarf_block *block = attr->as_block ();
result = block->data;
*len = block->size;
}
break;
/* The DW_AT_const_value attributes are supposed to carry the
symbol's value "represented as it would be on the target
architecture." By the time we get here, it's already been
converted to host endianness, so we just need to sign- or
zero-extend it as appropriate. */
case DW_FORM_data1:
type = die_type (die, cu);
result = dwarf2_const_value_data (attr, obstack, cu, &value, 8);
if (result == NULL)
result = write_constant_as_bytes (obstack, byte_order,
type, value, len);
break;
case DW_FORM_data2:
type = die_type (die, cu);
result = dwarf2_const_value_data (attr, obstack, cu, &value, 16);
if (result == NULL)
result = write_constant_as_bytes (obstack, byte_order,
type, value, len);
break;
case DW_FORM_data4:
type = die_type (die, cu);
result = dwarf2_const_value_data (attr, obstack, cu, &value, 32);
if (result == NULL)
result = write_constant_as_bytes (obstack, byte_order,
type, value, len);
break;
case DW_FORM_data8:
type = die_type (die, cu);
result = dwarf2_const_value_data (attr, obstack, cu, &value, 64);
if (result == NULL)
result = write_constant_as_bytes (obstack, byte_order,
type, value, len);
break;
case DW_FORM_sdata:
case DW_FORM_implicit_const:
type = die_type (die, cu);
result = write_constant_as_bytes (obstack, byte_order,
type, attr->as_signed (), len);
break;
case DW_FORM_udata:
type = die_type (die, cu);
result = write_constant_as_bytes (obstack, byte_order,
type, attr->as_unsigned (), len);
break;
default:
complaint (_("unsupported const value attribute form: '%s'"),
dwarf_form_name (attr->form));
break;
}
return result;
}
/* See read.h. */
struct type *
dwarf2_fetch_die_type_sect_off (sect_offset sect_off, dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile,
const char **var_name)
{
struct die_info *die;
dwarf2_cu *cu = per_objfile->get_cu (per_cu);
if (cu == nullptr)
cu = load_cu (per_cu, per_objfile, false);
if (cu == nullptr)
return nullptr;
die = follow_die_offset (sect_off, per_cu->is_dwz, &cu);
if (!die)
return NULL;
if (var_name != nullptr)
*var_name = var_decl_name (die, cu);
return die_type (die, cu);
}
/* See read.h. */
struct type *
dwarf2_get_die_type (cu_offset die_offset, dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile)
{
sect_offset die_offset_sect = per_cu->sect_off + to_underlying (die_offset);
return get_die_type_at_offset (die_offset_sect, per_cu, per_objfile);
}
/* Follow type unit SIG_TYPE referenced by SRC_DIE.
On entry *REF_CU is the CU of SRC_DIE.
On exit *REF_CU is the CU of the result.
Returns NULL if the referenced DIE isn't found. */
static struct die_info *
follow_die_sig_1 (struct die_info *src_die, struct signatured_type *sig_type,
struct dwarf2_cu **ref_cu)
{
struct dwarf2_cu *sig_cu;
dwarf2_per_objfile *per_objfile = (*ref_cu)->per_objfile;
/* While it might be nice to assert sig_type->type == NULL here,
we can get here for DW_AT_imported_declaration where we need
the DIE not the type. */
/* If necessary, add it to the queue and load its DIEs.
Even if maybe_queue_comp_unit doesn't require us to load the CU's DIEs,
it doesn't mean they are currently loaded. Since we require them
to be loaded, we must check for ourselves. */
if (maybe_queue_comp_unit (*ref_cu, sig_type, per_objfile)
|| per_objfile->get_cu (sig_type) == nullptr)
read_signatured_type (sig_type, per_objfile);
sig_cu = per_objfile->get_cu (sig_type);
gdb_assert (sig_cu != NULL);
gdb_assert (to_underlying (sig_type->type_offset_in_section) != 0);
if (auto die_it = sig_cu->die_hash.find (sig_type->type_offset_in_section);
die_it != sig_cu->die_hash.end ())
{
/* For .gdb_index version 7 keep track of included TUs.
http://sourceware.org/bugzilla/show_bug.cgi?id=15021. */
if (per_objfile->per_bfd->index_table != NULL
&& !per_objfile->per_bfd->index_table->version_check ())
(*ref_cu)->per_cu->imported_symtabs.push_back (sig_cu->per_cu);
*ref_cu = sig_cu;
return *die_it;
}
return NULL;
}
/* Follow signatured type referenced by ATTR in SRC_DIE.
On entry *REF_CU is the CU of SRC_DIE.
On exit *REF_CU is the CU of the result.
The result is the DIE of the type.
If the referenced type cannot be found an error is thrown. */
static struct die_info *
follow_die_sig (struct die_info *src_die, const struct attribute *attr,
struct dwarf2_cu **ref_cu)
{
ULONGEST signature = attr->as_signature ();
struct signatured_type *sig_type;
struct die_info *die;
gdb_assert (attr->form == DW_FORM_ref_sig8);
sig_type = lookup_signatured_type (*ref_cu, signature);
/* sig_type will be NULL if the signatured type is missing from
the debug info. */
if (sig_type == NULL)
{
error (_(DWARF_ERROR_PREFIX
"Cannot find signatured DIE %s referenced from DIE at %s"
" [in module %s]"),
hex_string (signature), sect_offset_str (src_die->sect_off),
objfile_name ((*ref_cu)->per_objfile->objfile));
}
die = follow_die_sig_1 (src_die, sig_type, ref_cu);
if (die == NULL)
{
src_die->error_dump ();
error (_(DWARF_ERROR_PREFIX
"Problem reading signatured DIE %s referenced from DIE at %s"
" [in module %s]"),
hex_string (signature), sect_offset_str (src_die->sect_off),
objfile_name ((*ref_cu)->per_objfile->objfile));
}
return die;
}
/* Get the type specified by SIGNATURE referenced in DIE/CU,
reading in and processing the type unit if necessary. */
static struct type *
get_signatured_type (struct die_info *die, ULONGEST signature,
struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct signatured_type *sig_type;
struct dwarf2_cu *type_cu;
struct die_info *type_die;
struct type *type;
sig_type = lookup_signatured_type (cu, signature);
/* sig_type will be NULL if the signatured type is missing from
the debug info. */
if (sig_type == NULL)
{
complaint (_(DWARF_ERROR_PREFIX
"Cannot find signatured DIE %s referenced from DIE at %s"
" [in module %s]"),
hex_string (signature), sect_offset_str (die->sect_off),
objfile_name (per_objfile->objfile));
return build_error_marker_type (cu, die);
}
/* If we already know the type we're done. */
type = per_objfile->get_type_for_signatured_type (sig_type);
if (type != nullptr)
return type;
type_cu = cu;
type_die = follow_die_sig_1 (die, sig_type, &type_cu);
if (type_die != NULL)
{
/* N.B. We need to call get_die_type to ensure only one type for this DIE
is created. This is important, for example, because for c++ classes
we need TYPE_NAME set which is only done by new_symbol. Blech. */
type = read_type_die (type_die, type_cu);
if (type == NULL)
{
complaint (_(DWARF_ERROR_PREFIX
"Cannot build signatured type %s"
" referenced from DIE at %s [in module %s]"),
hex_string (signature), sect_offset_str (die->sect_off),
objfile_name (per_objfile->objfile));
type = build_error_marker_type (cu, die);
}
}
else
{
complaint (_(DWARF_ERROR_PREFIX
"Problem reading signatured DIE %s referenced"
" from DIE at %s [in module %s]"),
hex_string (signature), sect_offset_str (die->sect_off),
objfile_name (per_objfile->objfile));
type = build_error_marker_type (cu, die);
}
per_objfile->set_type_for_signatured_type (sig_type, type);
return type;
}
/* Get the type specified by the DW_AT_signature ATTR in DIE/CU,
reading in and processing the type unit if necessary. */
static struct type *
get_DW_AT_signature_type (struct die_info *die, const struct attribute *attr,
struct dwarf2_cu *cu) /* ARI: editCase function */
{
/* Yes, DW_AT_signature can use a non-ref_sig8 reference. */
if (attr->form_is_ref ())
{
struct dwarf2_cu *type_cu = cu;
struct die_info *type_die = follow_die_ref (die, attr, &type_cu);
return read_type_die (type_die, type_cu);
}
else if (attr->form == DW_FORM_ref_sig8)
{
return get_signatured_type (die, attr->as_signature (), cu);
}
else
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
complaint (_(DWARF_ERROR_PREFIX
"DW_AT_signature has bad form %s in DIE at %s"
" [in module %s]"),
dwarf_form_name (attr->form), sect_offset_str (die->sect_off),
objfile_name (per_objfile->objfile));
return build_error_marker_type (cu, die);
}
}
/* Load the DIEs associated with type unit PER_CU into memory. */
static void
load_full_type_unit (dwarf2_per_cu *per_cu, dwarf2_per_objfile *per_objfile)
{
struct signatured_type *sig_type;
/* We have the per_cu, but we need the signatured_type.
Fortunately this is an easy translation. */
gdb_assert (per_cu->is_debug_types);
sig_type = (struct signatured_type *) per_cu;
gdb_assert (per_objfile->get_cu (per_cu) == nullptr);
read_signatured_type (sig_type, per_objfile);
gdb_assert (per_objfile->get_cu (per_cu) != nullptr);
}
/* Read in a signatured type and build its CU and DIEs.
If the type is a stub for the real type in a DWO file,
read in the real type from the DWO file as well. */
static void
read_signatured_type (signatured_type *sig_type,
dwarf2_per_objfile *per_objfile)
{
gdb_assert (sig_type->is_debug_types);
gdb_assert (per_objfile->get_cu (sig_type) == nullptr);
cutu_reader reader (sig_type, per_objfile, nullptr, nullptr, false,
language_minimal);
if (!reader.is_dummy ())
{
reader.read_all_dies ();
/* Save this dwarf2_cu in the per_objfile. The per_objfile owns it
now. */
per_objfile->set_cu (sig_type, reader.release_cu ());
}
sig_type->tu_read = 1;
}
/* See read.h. */
bool
decode_locdesc (struct dwarf_block *blk, struct dwarf2_cu *cu,
CORE_ADDR *result)
{
struct objfile *objfile = cu->per_objfile->objfile;
size_t i;
size_t size = blk->size;
const gdb_byte *data = blk->data;
CORE_ADDR stack[64];
int stacki;
unsigned int bytes_read;
gdb_byte op;
*result = 0;
i = 0;
stacki = 0;
stack[stacki] = 0;
stack[++stacki] = 0;
while (i < size)
{
op = data[i++];
switch (op)
{
case DW_OP_lit0:
case DW_OP_lit1:
case DW_OP_lit2:
case DW_OP_lit3:
case DW_OP_lit4:
case DW_OP_lit5:
case DW_OP_lit6:
case DW_OP_lit7:
case DW_OP_lit8:
case DW_OP_lit9:
case DW_OP_lit10:
case DW_OP_lit11:
case DW_OP_lit12:
case DW_OP_lit13:
case DW_OP_lit14:
case DW_OP_lit15:
case DW_OP_lit16:
case DW_OP_lit17:
case DW_OP_lit18:
case DW_OP_lit19:
case DW_OP_lit20:
case DW_OP_lit21:
case DW_OP_lit22:
case DW_OP_lit23:
case DW_OP_lit24:
case DW_OP_lit25:
case DW_OP_lit26:
case DW_OP_lit27:
case DW_OP_lit28:
case DW_OP_lit29:
case DW_OP_lit30:
case DW_OP_lit31:
stack[++stacki] = op - DW_OP_lit0;
break;
case DW_OP_addr:
stack[++stacki]
= (CORE_ADDR) cu->header.read_address (objfile->obfd.get (),
&data[i],
&bytes_read);
i += bytes_read;
break;
case DW_OP_const1u:
stack[++stacki] = read_1_byte (objfile->obfd.get (), &data[i]);
i += 1;
break;
case DW_OP_const1s:
stack[++stacki] = read_1_signed_byte (objfile->obfd.get (), &data[i]);
i += 1;
break;
case DW_OP_const2u:
stack[++stacki] = read_2_bytes (objfile->obfd.get (), &data[i]);
i += 2;
break;
case DW_OP_const2s:
stack[++stacki] = read_2_signed_bytes (objfile->obfd.get (), &data[i]);
i += 2;
break;
case DW_OP_const4u:
stack[++stacki] = read_4_bytes (objfile->obfd.get (), &data[i]);
i += 4;
break;
case DW_OP_const4s:
stack[++stacki] = read_4_signed_bytes (objfile->obfd.get (), &data[i]);
i += 4;
break;
case DW_OP_const8u:
stack[++stacki] = read_8_bytes (objfile->obfd.get (), &data[i]);
i += 8;
break;
case DW_OP_constu:
stack[++stacki] = read_unsigned_leb128 (NULL, (data + i),
&bytes_read);
i += bytes_read;
break;
case DW_OP_consts:
stack[++stacki] = read_signed_leb128 (NULL, (data + i), &bytes_read);
i += bytes_read;
break;
case DW_OP_dup:
stack[stacki + 1] = stack[stacki];
stacki++;
break;
case DW_OP_plus:
stack[stacki - 1] += stack[stacki];
stacki--;
break;
case DW_OP_plus_uconst:
stack[stacki] += read_unsigned_leb128 (NULL, (data + i),
&bytes_read);
i += bytes_read;
break;
case DW_OP_minus:
stack[stacki - 1] -= stack[stacki];
stacki--;
break;
case DW_OP_deref:
/* If we're not the last op, then we definitely can't encode
this using GDB's address_class enum. This is valid for partial
global symbols, although the variable's address will be bogus
in the psymtab. */
if (i < size)
return false;
break;
case DW_OP_addrx:
case DW_OP_GNU_addr_index:
case DW_OP_constx:
case DW_OP_GNU_const_index:
stack[++stacki]
= (CORE_ADDR) read_addr_index_from_leb128 (cu, &data[i],
&bytes_read);
i += bytes_read;
break;
default:
return false;
}
/* Enforce maximum stack depth of SIZE-1 to avoid writing
outside of the allocated space. Also enforce minimum>0. */
if (stacki >= ARRAY_SIZE (stack) - 1)
{
complaint (_("location description stack overflow"));
return false;
}
if (stacki <= 0)
{
complaint (_("location description stack underflow"));
return false;
}
}
*result = stack[stacki];
return true;
}
/* memory allocation interface */
static struct dwarf_block *
dwarf_alloc_block (struct dwarf2_cu *cu)
{
return XOBNEW (&cu->comp_unit_obstack, struct dwarf_block);
}
/* Macro support. */
/* An overload of dwarf_decode_macros that finds the correct section
and ensures it is read in before calling the other overload. */
static void
dwarf_decode_macros (struct dwarf2_cu *cu, unsigned int offset,
int section_is_gnu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
const struct line_header *lh = cu->line_header;
unsigned int offset_size = cu->header.offset_size;
struct dwarf2_section_info *section;
const char *section_name;
if (cu->dwo_unit != nullptr)
{
if (section_is_gnu)
{
section = &cu->dwo_unit->dwo_file->sections.macro;
section_name = ".debug_macro.dwo";
}
else
{
section = &cu->dwo_unit->dwo_file->sections.macinfo;
section_name = ".debug_macinfo.dwo";
}
}
else
{
if (section_is_gnu)
{
section = &per_objfile->per_bfd->macro;
section_name = ".debug_macro";
}
else
{
section = &per_objfile->per_bfd->macinfo;
section_name = ".debug_macinfo";
}
}
section->read (objfile);
if (section->buffer == nullptr)
{
complaint (_("missing %s section"), section_name);
return;
}
buildsym_compunit *builder = cu->get_builder ();
struct dwarf2_section_info *str_offsets_section;
struct dwarf2_section_info *str_section;
std::optional<ULONGEST> str_offsets_base;
if (cu->dwo_unit != nullptr)
{
str_offsets_section = &cu->dwo_unit->dwo_file
->sections.str_offsets;
str_section = &cu->dwo_unit->dwo_file->sections.str;
if (cu->header.version <= 4)
str_offsets_base = 0;
else
{
bfd *abfd = str_offsets_section->get_bfd_owner ();
unsigned int bytes_read = 0;
read_initial_length (abfd, str_offsets_section->buffer, &bytes_read,
false);
const bool is_dwarf64 = bytes_read != 4;
str_offsets_base = is_dwarf64 ? 16 : 8;
}
}
else
{
str_offsets_section = &per_objfile->per_bfd->str_offsets;
str_section = &per_objfile->per_bfd->str;
str_offsets_base = cu->str_offsets_base;
}
try
{
dwarf_decode_macros (per_objfile, builder, section, lh, offset_size,
offset, str_section, str_offsets_section,
str_offsets_base, section_is_gnu, cu);
}
catch (const gdb_exception_error &error)
{
/* Print the error and carry on with no (or partial) macro
information. */
exception_fprintf (gdb_stderr, error, _("While reading section %s: "),
section->get_name ());
}
}
/* Return the .debug_loc section to use for CU.
For DWO files use .debug_loc.dwo. */
static struct dwarf2_section_info *
cu_debug_loc_section (struct dwarf2_cu *cu)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
if (cu->dwo_unit)
{
struct dwo_sections *sections = &cu->dwo_unit->dwo_file->sections;
return cu->header.version >= 5 ? &sections->loclists : &sections->loc;
}
return (cu->header.version >= 5 ? &per_objfile->per_bfd->loclists
: &per_objfile->per_bfd->loc);
}
/* Return the .debug_rnglists section to use for CU. */
static struct dwarf2_section_info *
cu_debug_rnglists_section (struct dwarf2_cu *cu, dwarf_tag tag)
{
if (cu->header.version < 5)
error (_(".debug_rnglists section cannot be used in DWARF %d"),
cu->header.version);
struct dwarf2_per_objfile *dwarf2_per_objfile = cu->per_objfile;
/* Make sure we read the .debug_rnglists section from the file that
contains the DW_AT_ranges attribute we are reading. Normally that
would be the .dwo file, if there is one. However for DW_TAG_compile_unit
or DW_TAG_skeleton unit, we always want to read from objfile/linked
program. */
if (cu->dwo_unit != nullptr
&& tag != DW_TAG_compile_unit
&& tag != DW_TAG_skeleton_unit)
{
struct dwo_sections *sections = &cu->dwo_unit->dwo_file->sections;
if (sections->rnglists.size > 0)
return &sections->rnglists;
else
error (_(".debug_rnglists section is missing from .dwo file."));
}
return &dwarf2_per_objfile->per_bfd->rnglists;
}
/* A helper function that fills in a dwarf2_loclist_baton. */
static void
fill_in_loclist_baton (struct dwarf2_cu *cu,
struct dwarf2_loclist_baton *baton,
const struct attribute *attr)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct dwarf2_section_info *section = cu_debug_loc_section (cu);
section->read (per_objfile->objfile);
baton->per_objfile = per_objfile;
baton->per_cu = cu->per_cu;
gdb_assert (baton->per_cu);
/* We don't know how long the location list is, but make sure we
don't run off the edge of the section. */
baton->size = section->size - attr->as_unsigned ();
baton->data = section->buffer + attr->as_unsigned ();
if (cu->base_address.has_value ())
baton->base_address = *cu->base_address;
else
baton->base_address = {};
baton->from_dwo = cu->dwo_unit != NULL;
baton->dwarf_version = cu->header.version;
}
static void
dwarf2_symbol_mark_computed (const struct attribute *attr, struct symbol *sym,
struct dwarf2_cu *cu, int is_block)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct objfile *objfile = per_objfile->objfile;
struct dwarf2_section_info *section = cu_debug_loc_section (cu);
if (attr->form_is_section_offset ()
/* .debug_loc{,.dwo} may not exist at all, or the offset may be outside
the section. If so, fall through to the complaint in the
other branch. */
&& attr->as_unsigned () < section->get_size (objfile))
{
struct dwarf2_loclist_baton *baton;
baton = XOBNEW (&objfile->objfile_obstack, struct dwarf2_loclist_baton);
fill_in_loclist_baton (cu, baton, attr);
if (!cu->base_address.has_value ())
complaint (_("Location list used without "
"specifying the CU base address."));
sym->set_aclass_index ((is_block
? dwarf2_loclist_block_index
: dwarf2_loclist_index));
SYMBOL_LOCATION_BATON (sym) = baton;
}
else
{
struct dwarf2_locexpr_baton *baton;
baton = XOBNEW (&objfile->objfile_obstack, struct dwarf2_locexpr_baton);
baton->per_objfile = per_objfile;
baton->per_cu = cu->per_cu;
gdb_assert (baton->per_cu);
if (attr->form_is_block ())
{
/* Note that we're just copying the block's data pointer
here, not the actual data. We're still pointing into the
info_buffer for SYM's objfile; right now we never release
that buffer, but when we do clean up properly this may
need to change. */
struct dwarf_block *block = attr->as_block ();
baton->size = block->size;
baton->data = block->data;
}
else
{
dwarf2_invalid_attrib_class_complaint ("location description",
sym->natural_name ());
baton->size = 0;
}
sym->set_aclass_index ((is_block
? dwarf2_locexpr_block_index
: dwarf2_locexpr_index));
SYMBOL_LOCATION_BATON (sym) = baton;
}
}
/* See read.h. */
const comp_unit_head *
dwarf2_per_cu::get_header () const
{
if (!m_header_read_in)
{
const gdb_byte *info_ptr
= this->section->buffer + to_underlying (this->sect_off);
read_comp_unit_head (&m_header, info_ptr, this->section,
rcuh_kind::COMPILE);
m_header_read_in = true;
}
return &m_header;
}
/* See read.h. */
int
dwarf2_per_cu::addr_size () const
{
return this->get_header ()->addr_size;
}
/* See read.h. */
int
dwarf2_per_cu::offset_size () const
{
return this->get_header ()->offset_size;
}
/* See read.h. */
int
dwarf2_per_cu::ref_addr_size () const
{
const comp_unit_head *header = this->get_header ();
if (header->version == 2)
return header->addr_size;
else
return header->offset_size;
}
/* See read.h. */
void
dwarf2_per_cu::set_lang (enum language lang, dwarf_source_language dw_lang)
{
if (unit_type () == DW_UT_partial)
return;
/* Set if not set already. */
packed<language, LANGUAGE_BYTES> new_value = lang;
packed<language, LANGUAGE_BYTES> old_value = m_lang.exchange (new_value);
/* If already set, verify that it's the same value. */
gdb_assert (old_value == language_unknown
|| old_value == language_minimal
|| old_value == lang);
packed<dwarf_source_language, 2> new_dw = dw_lang;
packed<dwarf_source_language, 2> old_dw = m_dw_lang.exchange (new_dw);
gdb_assert (old_dw == 0 || old_dw == dw_lang);
}
/* See read.h. */
void
dwarf2_per_cu::ensure_lang (dwarf2_per_objfile *per_objfile)
{
if (lang (false) != language_unknown)
return;
/* Constructing this object will set the language as a side
effect. */
cutu_reader reader (this, per_objfile, nullptr, per_objfile->get_cu (this),
true, language_minimal, nullptr);
}
/* A helper function for dwarf2_find_containing_comp_unit that returns
the index of the result, and that searches a vector. It will
return a result even if the offset in question does not actually
occur in any CU. This is separate so that it can be unit
tested. */
static int
dwarf2_find_containing_comp_unit
(sect_offset sect_off,
unsigned int offset_in_dwz,
const std::vector<dwarf2_per_cu_up> &all_units)
{
int low, high;
low = 0;
high = all_units.size () - 1;
while (high > low)
{
int mid = low + (high - low) / 2;
dwarf2_per_cu *mid_cu = all_units[mid].get ();
if (mid_cu->is_dwz > offset_in_dwz
|| (mid_cu->is_dwz == offset_in_dwz
&& mid_cu->sect_off + mid_cu->length () > sect_off))
high = mid;
else
low = mid + 1;
}
gdb_assert (low == high);
return low;
}
/* See read.h. */
dwarf2_per_cu *
dwarf2_find_containing_comp_unit (sect_offset sect_off,
unsigned int offset_in_dwz,
dwarf2_per_bfd *per_bfd)
{
int low = dwarf2_find_containing_comp_unit
(sect_off, offset_in_dwz, per_bfd->all_units);
dwarf2_per_cu *this_cu = per_bfd->all_units[low].get ();
if (this_cu->is_dwz != offset_in_dwz || this_cu->sect_off > sect_off)
{
if (low == 0 || this_cu->is_dwz != offset_in_dwz)
error (_(DWARF_ERROR_PREFIX
"could not find CU containing offset %s [in module %s]"),
sect_offset_str (sect_off),
per_bfd->filename ());
gdb_assert (per_bfd->all_units[low-1]->sect_off
<= sect_off);
return per_bfd->all_units[low - 1].get ();
}
else
{
if (low == per_bfd->all_units.size () - 1
&& sect_off >= this_cu->sect_off + this_cu->length ())
error (_("invalid dwarf2 offset %s"), sect_offset_str (sect_off));
gdb_assert (sect_off < this_cu->sect_off + this_cu->length ());
return this_cu;
}
}
#if GDB_SELF_TEST
namespace selftests {
namespace find_containing_comp_unit {
static void
run_test ()
{
char dummy_per_bfd;
char dummy_section;
const auto create_dummy_per_cu = [&] (sect_offset sect_off,
unsigned int length,
bool is_dwz)
{
auto per_bfd = reinterpret_cast<dwarf2_per_bfd *> (&dummy_per_bfd);
auto section = reinterpret_cast<dwarf2_section_info *> (&dummy_section);
return dwarf2_per_cu_up (new dwarf2_per_cu (per_bfd, section, sect_off,
length, is_dwz));
};
/* Units in the main file. */
dwarf2_per_cu_up one = create_dummy_per_cu (sect_offset (0), 5, false);
dwarf2_per_cu *one_ptr = one.get ();
dwarf2_per_cu_up two
= create_dummy_per_cu (sect_offset (one->length ()), 7, false);
dwarf2_per_cu *two_ptr = two.get ();
/* Units in the supplementary (dwz) file. */
dwarf2_per_cu_up three = create_dummy_per_cu (sect_offset (0), 5, true);
dwarf2_per_cu *three_ptr = three.get ();
dwarf2_per_cu_up four
= create_dummy_per_cu (sect_offset (three->length ()), 7, true);
dwarf2_per_cu *four_ptr = four.get ();
std::vector<dwarf2_per_cu_up> units;
units.push_back (std::move (one));
units.push_back (std::move (two));
units.push_back (std::move (three));
units.push_back (std::move (four));
int result;
result = dwarf2_find_containing_comp_unit (sect_offset (0), 0, units);
SELF_CHECK (units[result].get () == one_ptr);
result = dwarf2_find_containing_comp_unit (sect_offset (3), 0, units);
SELF_CHECK (units[result].get () == one_ptr);
result = dwarf2_find_containing_comp_unit (sect_offset (5), 0, units);
SELF_CHECK (units[result].get () == two_ptr);
result = dwarf2_find_containing_comp_unit (sect_offset (0), 1, units);
SELF_CHECK (units[result].get () == three_ptr);
result = dwarf2_find_containing_comp_unit (sect_offset (3), 1, units);
SELF_CHECK (units[result].get () == three_ptr);
result = dwarf2_find_containing_comp_unit (sect_offset (5), 1, units);
SELF_CHECK (units[result].get () == four_ptr);
}
}
}
#endif /* GDB_SELF_TEST */
/* Initialize basic fields of dwarf_cu CU according to DIE
COMP_UNIT_DIE. If COMP_UNIT_DIE is NULL, the CU is assumed to be a
CU one with no contents; in this case default values are used for
the fields. */
void
cutu_reader::prepare_one_comp_unit (struct dwarf2_cu *cu,
enum language pretend_language)
{
struct attribute *attr;
if (m_top_level_die == nullptr)
{
cu->set_producer (nullptr);
cu->language_defn = language_def (pretend_language);
cu->per_cu->set_unit_type (DW_UT_compile);
cu->per_cu->set_lang (pretend_language, (dwarf_source_language) 0);
return;
}
cu->set_producer (dwarf2_string_attr (m_top_level_die, DW_AT_producer, cu));
/* Set the language we're debugging. */
attr = dwarf2_attr (m_top_level_die, DW_AT_language, cu);
enum language lang;
dwarf_source_language dw_lang = (dwarf_source_language) 0;
if (cu->producer_is_xlc_opencl ())
{
/* The XLCL doesn't generate DW_LANG_OpenCL because this
attribute is not standardised yet. As a workaround for the
language detection we fall back to the DW_AT_producer
string. */
lang = language_opencl;
dw_lang = DW_LANG_OpenCL;
}
else if (cu->producer_is_ggo ())
{
/* Similar hack for Go. */
lang = language_go;
dw_lang = DW_LANG_Go;
}
else if (attr != nullptr)
{
std::optional<ULONGEST> lang_val = attr->unsigned_constant ();
if (lang_val.has_value ())
{
lang = dwarf_lang_to_enum_language (*lang_val);
if (lang_val <= DW_LANG_hi_user)
dw_lang = (dwarf_source_language) *lang_val;
}
else
lang = language_minimal;
}
else
lang = pretend_language;
cu->language_defn = language_def (lang);
/* Initialize the lto_artificial field. */
attr = dwarf2_attr (m_top_level_die, DW_AT_name, cu);
if (attr != nullptr
&& cu->producer_is_gcc ()
&& attr->as_string () != nullptr
&& strcmp (attr->as_string (), "<artificial>") == 0)
cu->per_cu->lto_artificial = true;
switch (m_top_level_die->tag)
{
case DW_TAG_compile_unit:
cu->per_cu->set_unit_type (DW_UT_compile);
break;
case DW_TAG_partial_unit:
cu->per_cu->set_unit_type (DW_UT_partial);
break;
case DW_TAG_type_unit:
cu->per_cu->set_unit_type (DW_UT_type);
break;
default:
error (_(DWARF_ERROR_PREFIX "unexpected tag '%s' at offset %s"),
dwarf_tag_name (m_top_level_die->tag),
sect_offset_str (cu->per_cu->sect_off));
}
cu->per_cu->set_lang (lang, dw_lang);
}
/* See read.h. */
dwarf2_cu *
dwarf2_per_objfile::get_cu (dwarf2_per_cu *per_cu)
{
auto it = m_dwarf2_cus.find (per_cu);
if (it == m_dwarf2_cus.end ())
return nullptr;
return it->second.get ();
}
/* See read.h. */
void
dwarf2_per_objfile::set_cu (dwarf2_per_cu *per_cu, dwarf2_cu_up cu)
{
gdb_assert (this->get_cu (per_cu) == nullptr);
m_dwarf2_cus[per_cu] = std::move (cu);
}
/* See read.h. */
void
dwarf2_per_objfile::age_comp_units ()
{
dwarf_read_debug_printf_v ("running");
/* This is not expected to be called in the middle of CU expansion. There is
an invariant that if a CU is in the CUs-to-expand queue, its DIEs are
loaded in memory. Calling age_comp_units while the queue is in use could
make us free the DIEs for a CU that is in the queue and therefore break
that invariant. */
gdb_assert (!queue.has_value ());
/* Start by clearing all marks. */
for (const auto &pair : m_dwarf2_cus)
pair.second->clear_mark ();
/* Traverse all CUs, mark them and their dependencies if used recently
enough. */
for (const auto &pair : m_dwarf2_cus)
{
dwarf2_cu *cu = pair.second.get ();
cu->last_used++;
if (cu->last_used <= dwarf_max_cache_age)
cu->mark ();
}
/* Delete all CUs still not marked. */
for (auto it = m_dwarf2_cus.begin (); it != m_dwarf2_cus.end ();)
{
dwarf2_cu *cu = it->second.get ();
if (!cu->is_marked ())
{
dwarf_read_debug_printf_v ("deleting old CU %s",
sect_offset_str (cu->per_cu->sect_off));
it = m_dwarf2_cus.erase (it);
}
else
it++;
}
}
/* See read.h. */
void
dwarf2_per_objfile::remove_cu (dwarf2_per_cu *per_cu)
{
auto it = m_dwarf2_cus.find (per_cu);
if (it == m_dwarf2_cus.end ())
return;
m_dwarf2_cus.erase (it);
}
dwarf2_per_objfile::~dwarf2_per_objfile ()
{
remove_all_cus ();
}
/* Set the type associated with DIE to TYPE. Save it in CU's hash
table if necessary. For convenience, return TYPE.
The DIEs reading must have careful ordering to:
* Not cause infinite loops trying to read in DIEs as a prerequisite for
reading current DIE.
* Not trying to dereference contents of still incompletely read in types
while reading in other DIEs.
* Enable referencing still incompletely read in types just by a pointer to
the type without accessing its fields.
Therefore caller should follow these rules:
* Try to fetch any prerequisite types we may need to build this DIE type
before building the type and calling set_die_type.
* After building type call set_die_type for current DIE as soon as
possible before fetching more types to complete the current type.
* Make the type as complete as possible before fetching more types. */
static struct type *
set_die_type (struct die_info *die, struct type *type, struct dwarf2_cu *cu,
bool skip_data_location)
{
dwarf2_per_objfile *per_objfile = cu->per_objfile;
struct attribute *attr;
struct dynamic_prop prop;
/* For Ada types, make sure that the gnat-specific data is always
initialized (if not already set). There are a few types where
we should not be doing so, because the type-specific area is
already used to hold some other piece of info (eg: TYPE_CODE_FLT
where the type-specific area is used to store the floatformat).
But this is not a problem, because the gnat-specific information
is actually not needed for these types. */
if (need_gnat_info (cu)
&& type->code () != TYPE_CODE_FUNC
&& type->code () != TYPE_CODE_FLT
&& type->code () != TYPE_CODE_METHODPTR
&& type->code () != TYPE_CODE_MEMBERPTR
&& type->code () != TYPE_CODE_METHOD
&& type->code () != TYPE_CODE_FIXED_POINT
&& !HAVE_GNAT_AUX_INFO (type))
INIT_GNAT_SPECIFIC (type);
/* Read DW_AT_allocated and set in type. */
attr = dwarf2_attr (die, DW_AT_allocated, cu);
if (attr != NULL)
{
struct type *prop_type = cu->addr_sized_int_type (false);
if (attr_to_dynamic_prop (attr, die, cu, &prop, prop_type))
type->add_dyn_prop (DYN_PROP_ALLOCATED, prop);
}
/* Read DW_AT_associated and set in type. */
attr = dwarf2_attr (die, DW_AT_associated, cu);
if (attr != NULL)
{
struct type *prop_type = cu->addr_sized_int_type (false);
if (attr_to_dynamic_prop (attr, die, cu, &prop, prop_type))
type->add_dyn_prop (DYN_PROP_ASSOCIATED, prop);
}
/* Read DW_AT_rank and set in type. */
attr = dwarf2_attr (die, DW_AT_rank, cu);
if (attr != NULL)
{
struct type *prop_type = cu->addr_sized_int_type (false);
if (attr_to_dynamic_prop (attr, die, cu, &prop, prop_type))
type->add_dyn_prop (DYN_PROP_RANK, prop);
}
/* Read DW_AT_data_location and set in type. */
if (!skip_data_location)
{
attr = dwarf2_attr (die, DW_AT_data_location, cu);
if (attr_to_dynamic_prop (attr, die, cu, &prop, cu->addr_type ()))
type->add_dyn_prop (DYN_PROP_DATA_LOCATION, prop);
}
bool inserted
= per_objfile->die_type_hash.emplace
(per_cu_and_offset {cu->per_cu, die->sect_off}, type).second;
if (!inserted)
complaint (_("A problem internal to GDB: DIE %s has type already set"),
sect_offset_str (die->sect_off));
return type;
}
/* Look up the type for the die at SECT_OFF in PER_CU in die_type_hash,
or return NULL if the die does not have a saved type. */
static struct type *
get_die_type_at_offset (sect_offset sect_off, dwarf2_per_cu *per_cu,
dwarf2_per_objfile *per_objfile)
{
auto it = per_objfile->die_type_hash.find ({per_cu, sect_off});
return it != per_objfile->die_type_hash.end () ? it->second : nullptr;
}
/* Look up the type for DIE in CU in die_type_hash,
or return NULL if DIE does not have a saved type. */
static struct type *
get_die_type (struct die_info *die, struct dwarf2_cu *cu)
{
return get_die_type_at_offset (die->sect_off, cu->per_cu, cu->per_objfile);
}
struct cmd_list_element *set_dwarf_cmdlist;
struct cmd_list_element *show_dwarf_cmdlist;
static void
show_check_physname (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
gdb_printf (file,
_("Whether to check \"physname\" is %s.\n"),
value);
}
void _initialize_dwarf2_read ();
void
_initialize_dwarf2_read ()
{
add_setshow_prefix_cmd ("dwarf", class_maintenance,
_("\
Set DWARF specific variables.\n\
Configure DWARF variables such as the cache size."),
_("\
Show DWARF specific variables.\n\
Show DWARF variables such as the cache size."),
&set_dwarf_cmdlist, &show_dwarf_cmdlist,
&maintenance_set_cmdlist, &maintenance_show_cmdlist);
add_setshow_zinteger_cmd ("max-cache-age", class_obscure,
&dwarf_max_cache_age, _("\
Set the upper bound on the age of cached DWARF compilation units."), _("\
Show the upper bound on the age of cached DWARF compilation units."), _("\
A higher limit means that cached compilation units will be stored\n\
in memory longer, and more total memory will be used. Zero disables\n\
caching, which can slow down startup."),
NULL,
show_dwarf_max_cache_age,
&set_dwarf_cmdlist,
&show_dwarf_cmdlist);
add_setshow_boolean_cmd ("synchronous", class_obscure,
&dwarf_synchronous, _("\
Set whether DWARF is read synchronously."), _("\
Show whether DWARF is read synchronously."), _("\
By default, DWARF information is read in worker threads,\n\
and gdb will not generally wait for the reading to complete\n\
before continuing with other work, for example presenting a\n\
prompt to the user.\n\
Enabling this setting will cause the DWARF reader to always wait\n\
for debug info processing to be finished before gdb can proceed."),
nullptr,
show_dwarf_synchronous,
&set_dwarf_cmdlist,
&show_dwarf_cmdlist);
add_setshow_zuinteger_cmd ("dwarf-read", no_class, &dwarf_read_debug, _("\
Set debugging of the DWARF reader."), _("\
Show debugging of the DWARF reader."), _("\
When enabled (non-zero), debugging messages are printed during DWARF\n\
reading and symtab expansion. A value of 1 (one) provides basic\n\
information. A value greater than 1 provides more verbose information."),
NULL,
NULL,
&setdebuglist, &showdebuglist);
add_setshow_zuinteger_cmd ("dwarf-die", no_class, &dwarf_die_debug, _("\
Set debugging of the DWARF DIE reader."), _("\
Show debugging of the DWARF DIE reader."), _("\
When enabled (non-zero), DIEs are dumped after they are read in.\n\
The value is the maximum depth to print."),
NULL,
NULL,
&setdebuglist, &showdebuglist);
add_setshow_zuinteger_cmd ("dwarf-line", no_class, &dwarf_line_debug, _("\
Set debugging of the dwarf line reader."), _("\
Show debugging of the dwarf line reader."), _("\
When enabled (non-zero), line number entries are dumped as they are read in.\n\
A value of 1 (one) provides basic information.\n\
A value greater than 1 provides more verbose information."),
NULL,
NULL,
&setdebuglist, &showdebuglist);
add_setshow_boolean_cmd ("check-physname", no_class, &check_physname, _("\
Set cross-checking of \"physname\" code against demangler."), _("\
Show cross-checking of \"physname\" code against demangler."), _("\
When enabled, GDB's internal \"physname\" code is checked against\n\
the demangler."),
NULL, show_check_physname,
&setdebuglist, &showdebuglist);
dwarf2_locexpr_index = register_symbol_computed_impl (LOC_COMPUTED,
&dwarf2_locexpr_funcs);
dwarf2_loclist_index = register_symbol_computed_impl (LOC_COMPUTED,
&dwarf2_loclist_funcs);
ada_imported_index = register_symbol_computed_impl (LOC_COMPUTED,
&ada_imported_funcs);
dwarf2_locexpr_block_index = register_symbol_block_impl (LOC_BLOCK,
&dwarf2_block_frame_base_locexpr_funcs);
dwarf2_loclist_block_index = register_symbol_block_impl (LOC_BLOCK,
&dwarf2_block_frame_base_loclist_funcs);
ada_block_index = register_symbol_block_impl (LOC_BLOCK,
&ada_function_alias_funcs);
#if GDB_SELF_TEST
selftests::register_test ("dwarf2_find_containing_comp_unit",
selftests::find_containing_comp_unit::run_test);
#endif
}