blob: db261956c60544ec80101a6a893c1529810c1959 [file] [log] [blame]
/* Target-dependent code for the HP PA-RISC architecture.
Copyright (C) 1986-2021 Free Software Foundation, Inc.
Contributed by the Center for Software Science at the
University of Utah (pa-gdb-bugs@cs.utah.edu).
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/>. */
#include "defs.h"
#include "bfd.h"
#include "inferior.h"
#include "regcache.h"
#include "completer.h"
#include "osabi.h"
#include "arch-utils.h"
/* For argument passing to the inferior. */
#include "symtab.h"
#include "dis-asm.h"
#include "trad-frame.h"
#include "frame-unwind.h"
#include "frame-base.h"
#include "gdbcore.h"
#include "gdbcmd.h"
#include "gdbtypes.h"
#include "objfiles.h"
#include "hppa-tdep.h"
#include <algorithm>
static bool hppa_debug = false;
/* Some local constants. */
static const int hppa32_num_regs = 128;
static const int hppa64_num_regs = 96;
/* We use the objfile->obj_private pointer for two things:
* 1. An unwind table;
*
* 2. A pointer to any associated shared library object.
*
* #defines are used to help refer to these objects.
*/
/* Info about the unwind table associated with an object file.
* This is hung off of the "objfile->obj_private" pointer, and
* is allocated in the objfile's psymbol obstack. This allows
* us to have unique unwind info for each executable and shared
* library that we are debugging.
*/
struct hppa_unwind_info
{
struct unwind_table_entry *table; /* Pointer to unwind info */
struct unwind_table_entry *cache; /* Pointer to last entry we found */
int last; /* Index of last entry */
};
struct hppa_objfile_private
{
struct hppa_unwind_info *unwind_info; /* a pointer */
struct so_list *so_info; /* a pointer */
CORE_ADDR dp;
int dummy_call_sequence_reg;
CORE_ADDR dummy_call_sequence_addr;
};
/* hppa-specific object data -- unwind and solib info.
TODO/maybe: think about splitting this into two parts; the unwind data is
common to all hppa targets, but is only used in this file; we can register
that separately and make this static. The solib data is probably hpux-
specific, so we can create a separate extern objfile_data that is registered
by hppa-hpux-tdep.c and shared with pa64solib.c and somsolib.c. */
static const struct objfile_key<hppa_objfile_private,
gdb::noop_deleter<hppa_objfile_private>>
hppa_objfile_priv_data;
/* Get at various relevant fields of an instruction word. */
#define MASK_5 0x1f
#define MASK_11 0x7ff
#define MASK_14 0x3fff
#define MASK_21 0x1fffff
/* Sizes (in bytes) of the native unwind entries. */
#define UNWIND_ENTRY_SIZE 16
#define STUB_UNWIND_ENTRY_SIZE 8
/* Routines to extract various sized constants out of hppa
instructions. */
/* This assumes that no garbage lies outside of the lower bits of
value. */
static int
hppa_sign_extend (unsigned val, unsigned bits)
{
return (int) (val >> (bits - 1) ? (-(1 << bits)) | val : val);
}
/* For many immediate values the sign bit is the low bit! */
static int
hppa_low_hppa_sign_extend (unsigned val, unsigned bits)
{
return (int) ((val & 0x1 ? (-(1 << (bits - 1))) : 0) | val >> 1);
}
/* Extract the bits at positions between FROM and TO, using HP's numbering
(MSB = 0). */
int
hppa_get_field (unsigned word, int from, int to)
{
return ((word) >> (31 - (to)) & ((1 << ((to) - (from) + 1)) - 1));
}
/* Extract the immediate field from a ld{bhw}s instruction. */
int
hppa_extract_5_load (unsigned word)
{
return hppa_low_hppa_sign_extend (word >> 16 & MASK_5, 5);
}
/* Extract the immediate field from a break instruction. */
unsigned
hppa_extract_5r_store (unsigned word)
{
return (word & MASK_5);
}
/* Extract the immediate field from a {sr}sm instruction. */
unsigned
hppa_extract_5R_store (unsigned word)
{
return (word >> 16 & MASK_5);
}
/* Extract a 14 bit immediate field. */
int
hppa_extract_14 (unsigned word)
{
return hppa_low_hppa_sign_extend (word & MASK_14, 14);
}
/* Extract a 21 bit constant. */
int
hppa_extract_21 (unsigned word)
{
int val;
word &= MASK_21;
word <<= 11;
val = hppa_get_field (word, 20, 20);
val <<= 11;
val |= hppa_get_field (word, 9, 19);
val <<= 2;
val |= hppa_get_field (word, 5, 6);
val <<= 5;
val |= hppa_get_field (word, 0, 4);
val <<= 2;
val |= hppa_get_field (word, 7, 8);
return hppa_sign_extend (val, 21) << 11;
}
/* extract a 17 bit constant from branch instructions, returning the
19 bit signed value. */
int
hppa_extract_17 (unsigned word)
{
return hppa_sign_extend (hppa_get_field (word, 19, 28) |
hppa_get_field (word, 29, 29) << 10 |
hppa_get_field (word, 11, 15) << 11 |
(word & 0x1) << 16, 17) << 2;
}
CORE_ADDR
hppa_symbol_address(const char *sym)
{
struct bound_minimal_symbol minsym;
minsym = lookup_minimal_symbol (sym, NULL, NULL);
if (minsym.minsym)
return BMSYMBOL_VALUE_ADDRESS (minsym);
else
return (CORE_ADDR)-1;
}
static struct hppa_objfile_private *
hppa_init_objfile_priv_data (struct objfile *objfile)
{
hppa_objfile_private *priv
= OBSTACK_ZALLOC (&objfile->objfile_obstack, hppa_objfile_private);
hppa_objfile_priv_data.set (objfile, priv);
return priv;
}
/* Compare the start address for two unwind entries returning 1 if
the first address is larger than the second, -1 if the second is
larger than the first, and zero if they are equal. */
static int
compare_unwind_entries (const void *arg1, const void *arg2)
{
const struct unwind_table_entry *a = (const struct unwind_table_entry *) arg1;
const struct unwind_table_entry *b = (const struct unwind_table_entry *) arg2;
if (a->region_start > b->region_start)
return 1;
else if (a->region_start < b->region_start)
return -1;
else
return 0;
}
static void
record_text_segment_lowaddr (bfd *abfd, asection *section, void *data)
{
if ((section->flags & (SEC_ALLOC | SEC_LOAD | SEC_READONLY))
== (SEC_ALLOC | SEC_LOAD | SEC_READONLY))
{
bfd_vma value = section->vma - section->filepos;
CORE_ADDR *low_text_segment_address = (CORE_ADDR *)data;
if (value < *low_text_segment_address)
*low_text_segment_address = value;
}
}
static void
internalize_unwinds (struct objfile *objfile, struct unwind_table_entry *table,
asection *section, unsigned int entries,
size_t size, CORE_ADDR text_offset)
{
/* We will read the unwind entries into temporary memory, then
fill in the actual unwind table. */
if (size > 0)
{
struct gdbarch *gdbarch = objfile->arch ();
unsigned long tmp;
unsigned i;
char *buf = (char *) alloca (size);
CORE_ADDR low_text_segment_address;
/* For ELF targets, then unwinds are supposed to
be segment relative offsets instead of absolute addresses.
Note that when loading a shared library (text_offset != 0) the
unwinds are already relative to the text_offset that will be
passed in. */
if (gdbarch_tdep (gdbarch)->is_elf && text_offset == 0)
{
low_text_segment_address = -1;
bfd_map_over_sections (objfile->obfd,
record_text_segment_lowaddr,
&low_text_segment_address);
text_offset = low_text_segment_address;
}
else if (gdbarch_tdep (gdbarch)->solib_get_text_base)
{
text_offset = gdbarch_tdep (gdbarch)->solib_get_text_base (objfile);
}
bfd_get_section_contents (objfile->obfd, section, buf, 0, size);
/* Now internalize the information being careful to handle host/target
endian issues. */
for (i = 0; i < entries; i++)
{
table[i].region_start = bfd_get_32 (objfile->obfd,
(bfd_byte *) buf);
table[i].region_start += text_offset;
buf += 4;
table[i].region_end = bfd_get_32 (objfile->obfd, (bfd_byte *) buf);
table[i].region_end += text_offset;
buf += 4;
tmp = bfd_get_32 (objfile->obfd, (bfd_byte *) buf);
buf += 4;
table[i].Cannot_unwind = (tmp >> 31) & 0x1;
table[i].Millicode = (tmp >> 30) & 0x1;
table[i].Millicode_save_sr0 = (tmp >> 29) & 0x1;
table[i].Region_description = (tmp >> 27) & 0x3;
table[i].reserved = (tmp >> 26) & 0x1;
table[i].Entry_SR = (tmp >> 25) & 0x1;
table[i].Entry_FR = (tmp >> 21) & 0xf;
table[i].Entry_GR = (tmp >> 16) & 0x1f;
table[i].Args_stored = (tmp >> 15) & 0x1;
table[i].Variable_Frame = (tmp >> 14) & 0x1;
table[i].Separate_Package_Body = (tmp >> 13) & 0x1;
table[i].Frame_Extension_Millicode = (tmp >> 12) & 0x1;
table[i].Stack_Overflow_Check = (tmp >> 11) & 0x1;
table[i].Two_Instruction_SP_Increment = (tmp >> 10) & 0x1;
table[i].sr4export = (tmp >> 9) & 0x1;
table[i].cxx_info = (tmp >> 8) & 0x1;
table[i].cxx_try_catch = (tmp >> 7) & 0x1;
table[i].sched_entry_seq = (tmp >> 6) & 0x1;
table[i].reserved1 = (tmp >> 5) & 0x1;
table[i].Save_SP = (tmp >> 4) & 0x1;
table[i].Save_RP = (tmp >> 3) & 0x1;
table[i].Save_MRP_in_frame = (tmp >> 2) & 0x1;
table[i].save_r19 = (tmp >> 1) & 0x1;
table[i].Cleanup_defined = tmp & 0x1;
tmp = bfd_get_32 (objfile->obfd, (bfd_byte *) buf);
buf += 4;
table[i].MPE_XL_interrupt_marker = (tmp >> 31) & 0x1;
table[i].HP_UX_interrupt_marker = (tmp >> 30) & 0x1;
table[i].Large_frame = (tmp >> 29) & 0x1;
table[i].alloca_frame = (tmp >> 28) & 0x1;
table[i].reserved2 = (tmp >> 27) & 0x1;
table[i].Total_frame_size = tmp & 0x7ffffff;
/* Stub unwinds are handled elsewhere. */
table[i].stub_unwind.stub_type = 0;
table[i].stub_unwind.padding = 0;
}
}
}
/* Read in the backtrace information stored in the `$UNWIND_START$' section of
the object file. This info is used mainly by find_unwind_entry() to find
out the stack frame size and frame pointer used by procedures. We put
everything on the psymbol obstack in the objfile so that it automatically
gets freed when the objfile is destroyed. */
static void
read_unwind_info (struct objfile *objfile)
{
asection *unwind_sec, *stub_unwind_sec;
size_t unwind_size, stub_unwind_size, total_size;
unsigned index, unwind_entries;
unsigned stub_entries, total_entries;
CORE_ADDR text_offset;
struct hppa_unwind_info *ui;
struct hppa_objfile_private *obj_private;
text_offset = objfile->text_section_offset ();
ui = (struct hppa_unwind_info *) obstack_alloc (&objfile->objfile_obstack,
sizeof (struct hppa_unwind_info));
ui->table = NULL;
ui->cache = NULL;
ui->last = -1;
/* For reasons unknown the HP PA64 tools generate multiple unwinder
sections in a single executable. So we just iterate over every
section in the BFD looking for unwinder sections instead of trying
to do a lookup with bfd_get_section_by_name.
First determine the total size of the unwind tables so that we
can allocate memory in a nice big hunk. */
total_entries = 0;
for (unwind_sec = objfile->obfd->sections;
unwind_sec;
unwind_sec = unwind_sec->next)
{
if (strcmp (unwind_sec->name, "$UNWIND_START$") == 0
|| strcmp (unwind_sec->name, ".PARISC.unwind") == 0)
{
unwind_size = bfd_section_size (unwind_sec);
unwind_entries = unwind_size / UNWIND_ENTRY_SIZE;
total_entries += unwind_entries;
}
}
/* Now compute the size of the stub unwinds. Note the ELF tools do not
use stub unwinds at the current time. */
stub_unwind_sec = bfd_get_section_by_name (objfile->obfd, "$UNWIND_END$");
if (stub_unwind_sec)
{
stub_unwind_size = bfd_section_size (stub_unwind_sec);
stub_entries = stub_unwind_size / STUB_UNWIND_ENTRY_SIZE;
}
else
{
stub_unwind_size = 0;
stub_entries = 0;
}
/* Compute total number of unwind entries and their total size. */
total_entries += stub_entries;
total_size = total_entries * sizeof (struct unwind_table_entry);
/* Allocate memory for the unwind table. */
ui->table = (struct unwind_table_entry *)
obstack_alloc (&objfile->objfile_obstack, total_size);
ui->last = total_entries - 1;
/* Now read in each unwind section and internalize the standard unwind
entries. */
index = 0;
for (unwind_sec = objfile->obfd->sections;
unwind_sec;
unwind_sec = unwind_sec->next)
{
if (strcmp (unwind_sec->name, "$UNWIND_START$") == 0
|| strcmp (unwind_sec->name, ".PARISC.unwind") == 0)
{
unwind_size = bfd_section_size (unwind_sec);
unwind_entries = unwind_size / UNWIND_ENTRY_SIZE;
internalize_unwinds (objfile, &ui->table[index], unwind_sec,
unwind_entries, unwind_size, text_offset);
index += unwind_entries;
}
}
/* Now read in and internalize the stub unwind entries. */
if (stub_unwind_size > 0)
{
unsigned int i;
char *buf = (char *) alloca (stub_unwind_size);
/* Read in the stub unwind entries. */
bfd_get_section_contents (objfile->obfd, stub_unwind_sec, buf,
0, stub_unwind_size);
/* Now convert them into regular unwind entries. */
for (i = 0; i < stub_entries; i++, index++)
{
/* Clear out the next unwind entry. */
memset (&ui->table[index], 0, sizeof (struct unwind_table_entry));
/* Convert offset & size into region_start and region_end.
Stuff away the stub type into "reserved" fields. */
ui->table[index].region_start = bfd_get_32 (objfile->obfd,
(bfd_byte *) buf);
ui->table[index].region_start += text_offset;
buf += 4;
ui->table[index].stub_unwind.stub_type = bfd_get_8 (objfile->obfd,
(bfd_byte *) buf);
buf += 2;
ui->table[index].region_end
= ui->table[index].region_start + 4 *
(bfd_get_16 (objfile->obfd, (bfd_byte *) buf) - 1);
buf += 2;
}
}
/* Unwind table needs to be kept sorted. */
qsort (ui->table, total_entries, sizeof (struct unwind_table_entry),
compare_unwind_entries);
/* Keep a pointer to the unwind information. */
obj_private = hppa_objfile_priv_data.get (objfile);
if (obj_private == NULL)
obj_private = hppa_init_objfile_priv_data (objfile);
obj_private->unwind_info = ui;
}
/* Lookup the unwind (stack backtrace) info for the given PC. We search all
of the objfiles seeking the unwind table entry for this PC. Each objfile
contains a sorted list of struct unwind_table_entry. Since we do a binary
search of the unwind tables, we depend upon them to be sorted. */
struct unwind_table_entry *
find_unwind_entry (CORE_ADDR pc)
{
int first, middle, last;
struct hppa_objfile_private *priv;
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, "{ find_unwind_entry %s -> ",
hex_string (pc));
/* A function at address 0? Not in HP-UX! */
if (pc == (CORE_ADDR) 0)
{
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, "NULL }\n");
return NULL;
}
for (objfile *objfile : current_program_space->objfiles ())
{
struct hppa_unwind_info *ui;
ui = NULL;
priv = hppa_objfile_priv_data.get (objfile);
if (priv)
ui = ((struct hppa_objfile_private *) priv)->unwind_info;
if (!ui)
{
read_unwind_info (objfile);
priv = hppa_objfile_priv_data.get (objfile);
if (priv == NULL)
error (_("Internal error reading unwind information."));
ui = ((struct hppa_objfile_private *) priv)->unwind_info;
}
/* First, check the cache. */
if (ui->cache
&& pc >= ui->cache->region_start
&& pc <= ui->cache->region_end)
{
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, "%s (cached) }\n",
hex_string ((uintptr_t) ui->cache));
return ui->cache;
}
/* Not in the cache, do a binary search. */
first = 0;
last = ui->last;
while (first <= last)
{
middle = (first + last) / 2;
if (pc >= ui->table[middle].region_start
&& pc <= ui->table[middle].region_end)
{
ui->cache = &ui->table[middle];
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, "%s }\n",
hex_string ((uintptr_t) ui->cache));
return &ui->table[middle];
}
if (pc < ui->table[middle].region_start)
last = middle - 1;
else
first = middle + 1;
}
}
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, "NULL (not found) }\n");
return NULL;
}
/* Implement the stack_frame_destroyed_p gdbarch method.
The epilogue is defined here as the area either on the `bv' instruction
itself or an instruction which destroys the function's stack frame.
We do not assume that the epilogue is at the end of a function as we can
also have return sequences in the middle of a function. */
static int
hppa_stack_frame_destroyed_p (struct gdbarch *gdbarch, CORE_ADDR pc)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
unsigned long status;
unsigned int inst;
gdb_byte buf[4];
status = target_read_memory (pc, buf, 4);
if (status != 0)
return 0;
inst = extract_unsigned_integer (buf, 4, byte_order);
/* The most common way to perform a stack adjustment ldo X(sp),sp
We are destroying a stack frame if the offset is negative. */
if ((inst & 0xffffc000) == 0x37de0000
&& hppa_extract_14 (inst) < 0)
return 1;
/* ldw,mb D(sp),X or ldd,mb D(sp),X */
if (((inst & 0x0fc010e0) == 0x0fc010e0
|| (inst & 0x0fc010e0) == 0x0fc010e0)
&& hppa_extract_14 (inst) < 0)
return 1;
/* bv %r0(%rp) or bv,n %r0(%rp) */
if (inst == 0xe840c000 || inst == 0xe840c002)
return 1;
return 0;
}
constexpr gdb_byte hppa_break_insn[] = {0x00, 0x01, 0x00, 0x04};
typedef BP_MANIPULATION (hppa_break_insn) hppa_breakpoint;
/* Return the name of a register. */
static const char *
hppa32_register_name (struct gdbarch *gdbarch, int i)
{
static const char *names[] = {
"flags", "r1", "rp", "r3",
"r4", "r5", "r6", "r7",
"r8", "r9", "r10", "r11",
"r12", "r13", "r14", "r15",
"r16", "r17", "r18", "r19",
"r20", "r21", "r22", "r23",
"r24", "r25", "r26", "dp",
"ret0", "ret1", "sp", "r31",
"sar", "pcoqh", "pcsqh", "pcoqt",
"pcsqt", "eiem", "iir", "isr",
"ior", "ipsw", "goto", "sr4",
"sr0", "sr1", "sr2", "sr3",
"sr5", "sr6", "sr7", "cr0",
"cr8", "cr9", "ccr", "cr12",
"cr13", "cr24", "cr25", "cr26",
"mpsfu_high","mpsfu_low","mpsfu_ovflo","pad",
"fpsr", "fpe1", "fpe2", "fpe3",
"fpe4", "fpe5", "fpe6", "fpe7",
"fr4", "fr4R", "fr5", "fr5R",
"fr6", "fr6R", "fr7", "fr7R",
"fr8", "fr8R", "fr9", "fr9R",
"fr10", "fr10R", "fr11", "fr11R",
"fr12", "fr12R", "fr13", "fr13R",
"fr14", "fr14R", "fr15", "fr15R",
"fr16", "fr16R", "fr17", "fr17R",
"fr18", "fr18R", "fr19", "fr19R",
"fr20", "fr20R", "fr21", "fr21R",
"fr22", "fr22R", "fr23", "fr23R",
"fr24", "fr24R", "fr25", "fr25R",
"fr26", "fr26R", "fr27", "fr27R",
"fr28", "fr28R", "fr29", "fr29R",
"fr30", "fr30R", "fr31", "fr31R"
};
if (i < 0 || i >= (sizeof (names) / sizeof (*names)))
return NULL;
else
return names[i];
}
static const char *
hppa64_register_name (struct gdbarch *gdbarch, int i)
{
static const char *names[] = {
"flags", "r1", "rp", "r3",
"r4", "r5", "r6", "r7",
"r8", "r9", "r10", "r11",
"r12", "r13", "r14", "r15",
"r16", "r17", "r18", "r19",
"r20", "r21", "r22", "r23",
"r24", "r25", "r26", "dp",
"ret0", "ret1", "sp", "r31",
"sar", "pcoqh", "pcsqh", "pcoqt",
"pcsqt", "eiem", "iir", "isr",
"ior", "ipsw", "goto", "sr4",
"sr0", "sr1", "sr2", "sr3",
"sr5", "sr6", "sr7", "cr0",
"cr8", "cr9", "ccr", "cr12",
"cr13", "cr24", "cr25", "cr26",
"mpsfu_high","mpsfu_low","mpsfu_ovflo","pad",
"fpsr", "fpe1", "fpe2", "fpe3",
"fr4", "fr5", "fr6", "fr7",
"fr8", "fr9", "fr10", "fr11",
"fr12", "fr13", "fr14", "fr15",
"fr16", "fr17", "fr18", "fr19",
"fr20", "fr21", "fr22", "fr23",
"fr24", "fr25", "fr26", "fr27",
"fr28", "fr29", "fr30", "fr31"
};
if (i < 0 || i >= (sizeof (names) / sizeof (*names)))
return NULL;
else
return names[i];
}
/* Map dwarf DBX register numbers to GDB register numbers. */
static int
hppa64_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int reg)
{
/* The general registers and the sar are the same in both sets. */
if (reg >= 0 && reg <= 32)
return reg;
/* fr4-fr31 are mapped from 72 in steps of 2. */
if (reg >= 72 && reg < 72 + 28 * 2 && !(reg & 1))
return HPPA64_FP4_REGNUM + (reg - 72) / 2;
return -1;
}
/* This function pushes a stack frame with arguments as part of the
inferior function calling mechanism.
This is the version of the function for the 32-bit PA machines, in
which later arguments appear at lower addresses. (The stack always
grows towards higher addresses.)
We simply allocate the appropriate amount of stack space and put
arguments into their proper slots. */
static CORE_ADDR
hppa32_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
struct regcache *regcache, CORE_ADDR bp_addr,
int nargs, struct value **args, CORE_ADDR sp,
function_call_return_method return_method,
CORE_ADDR struct_addr)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
/* Stack base address at which any pass-by-reference parameters are
stored. */
CORE_ADDR struct_end = 0;
/* Stack base address at which the first parameter is stored. */
CORE_ADDR param_end = 0;
/* Two passes. First pass computes the location of everything,
second pass writes the bytes out. */
int write_pass;
/* Global pointer (r19) of the function we are trying to call. */
CORE_ADDR gp;
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
for (write_pass = 0; write_pass < 2; write_pass++)
{
CORE_ADDR struct_ptr = 0;
/* The first parameter goes into sp-36, each stack slot is 4-bytes.
struct_ptr is adjusted for each argument below, so the first
argument will end up at sp-36. */
CORE_ADDR param_ptr = 32;
int i;
int small_struct = 0;
for (i = 0; i < nargs; i++)
{
struct value *arg = args[i];
struct type *type = check_typedef (value_type (arg));
/* The corresponding parameter that is pushed onto the
stack, and [possibly] passed in a register. */
gdb_byte param_val[8];
int param_len;
memset (param_val, 0, sizeof param_val);
if (TYPE_LENGTH (type) > 8)
{
/* Large parameter, pass by reference. Store the value
in "struct" area and then pass its address. */
param_len = 4;
struct_ptr += align_up (TYPE_LENGTH (type), 8);
if (write_pass)
write_memory (struct_end - struct_ptr, value_contents (arg),
TYPE_LENGTH (type));
store_unsigned_integer (param_val, 4, byte_order,
struct_end - struct_ptr);
}
else if (type->code () == TYPE_CODE_INT
|| type->code () == TYPE_CODE_ENUM)
{
/* Integer value store, right aligned. "unpack_long"
takes care of any sign-extension problems. */
param_len = align_up (TYPE_LENGTH (type), 4);
store_unsigned_integer (param_val, param_len, byte_order,
unpack_long (type,
value_contents (arg)));
}
else if (type->code () == TYPE_CODE_FLT)
{
/* Floating point value store, right aligned. */
param_len = align_up (TYPE_LENGTH (type), 4);
memcpy (param_val, value_contents (arg), param_len);
}
else
{
param_len = align_up (TYPE_LENGTH (type), 4);
/* Small struct value are stored right-aligned. */
memcpy (param_val + param_len - TYPE_LENGTH (type),
value_contents (arg), TYPE_LENGTH (type));
/* Structures of size 5, 6 and 7 bytes are special in that
the higher-ordered word is stored in the lower-ordered
argument, and even though it is a 8-byte quantity the
registers need not be 8-byte aligned. */
if (param_len > 4 && param_len < 8)
small_struct = 1;
}
param_ptr += param_len;
if (param_len == 8 && !small_struct)
param_ptr = align_up (param_ptr, 8);
/* First 4 non-FP arguments are passed in gr26-gr23.
First 4 32-bit FP arguments are passed in fr4L-fr7L.
First 2 64-bit FP arguments are passed in fr5 and fr7.
The rest go on the stack, starting at sp-36, towards lower
addresses. 8-byte arguments must be aligned to a 8-byte
stack boundary. */
if (write_pass)
{
write_memory (param_end - param_ptr, param_val, param_len);
/* There are some cases when we don't know the type
expected by the callee (e.g. for variadic functions), so
pass the parameters in both general and fp regs. */
if (param_ptr <= 48)
{
int grreg = 26 - (param_ptr - 36) / 4;
int fpLreg = 72 + (param_ptr - 36) / 4 * 2;
int fpreg = 74 + (param_ptr - 32) / 8 * 4;
regcache->cooked_write (grreg, param_val);
regcache->cooked_write (fpLreg, param_val);
if (param_len > 4)
{
regcache->cooked_write (grreg + 1, param_val + 4);
regcache->cooked_write (fpreg, param_val);
regcache->cooked_write (fpreg + 1, param_val + 4);
}
}
}
}
/* Update the various stack pointers. */
if (!write_pass)
{
struct_end = sp + align_up (struct_ptr, 64);
/* PARAM_PTR already accounts for all the arguments passed
by the user. However, the ABI mandates minimum stack
space allocations for outgoing arguments. The ABI also
mandates minimum stack alignments which we must
preserve. */
param_end = struct_end + align_up (param_ptr, 64);
}
}
/* If a structure has to be returned, set up register 28 to hold its
address. */
if (return_method == return_method_struct)
regcache_cooked_write_unsigned (regcache, 28, struct_addr);
gp = tdep->find_global_pointer (gdbarch, function);
if (gp != 0)
regcache_cooked_write_unsigned (regcache, 19, gp);
/* Set the return address. */
if (!gdbarch_push_dummy_code_p (gdbarch))
regcache_cooked_write_unsigned (regcache, HPPA_RP_REGNUM, bp_addr);
/* Update the Stack Pointer. */
regcache_cooked_write_unsigned (regcache, HPPA_SP_REGNUM, param_end);
return param_end;
}
/* The 64-bit PA-RISC calling conventions are documented in "64-Bit
Runtime Architecture for PA-RISC 2.0", which is distributed as part
as of the HP-UX Software Transition Kit (STK). This implementation
is based on version 3.3, dated October 6, 1997. */
/* Check whether TYPE is an "Integral or Pointer Scalar Type". */
static int
hppa64_integral_or_pointer_p (const struct type *type)
{
switch (type->code ())
{
case TYPE_CODE_INT:
case TYPE_CODE_BOOL:
case TYPE_CODE_CHAR:
case TYPE_CODE_ENUM:
case TYPE_CODE_RANGE:
{
int len = TYPE_LENGTH (type);
return (len == 1 || len == 2 || len == 4 || len == 8);
}
case TYPE_CODE_PTR:
case TYPE_CODE_REF:
case TYPE_CODE_RVALUE_REF:
return (TYPE_LENGTH (type) == 8);
default:
break;
}
return 0;
}
/* Check whether TYPE is a "Floating Scalar Type". */
static int
hppa64_floating_p (const struct type *type)
{
switch (type->code ())
{
case TYPE_CODE_FLT:
{
int len = TYPE_LENGTH (type);
return (len == 4 || len == 8 || len == 16);
}
default:
break;
}
return 0;
}
/* If CODE points to a function entry address, try to look up the corresponding
function descriptor and return its address instead. If CODE is not a
function entry address, then just return it unchanged. */
static CORE_ADDR
hppa64_convert_code_addr_to_fptr (struct gdbarch *gdbarch, CORE_ADDR code)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
struct obj_section *sec, *opd;
sec = find_pc_section (code);
if (!sec)
return code;
/* If CODE is in a data section, assume it's already a fptr. */
if (!(sec->the_bfd_section->flags & SEC_CODE))
return code;
ALL_OBJFILE_OSECTIONS (sec->objfile, opd)
{
if (strcmp (opd->the_bfd_section->name, ".opd") == 0)
break;
}
if (opd < sec->objfile->sections_end)
{
for (CORE_ADDR addr = opd->addr (); addr < opd->endaddr (); addr += 2 * 8)
{
ULONGEST opdaddr;
gdb_byte tmp[8];
if (target_read_memory (addr, tmp, sizeof (tmp)))
break;
opdaddr = extract_unsigned_integer (tmp, sizeof (tmp), byte_order);
if (opdaddr == code)
return addr - 16;
}
}
return code;
}
static CORE_ADDR
hppa64_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
struct regcache *regcache, CORE_ADDR bp_addr,
int nargs, struct value **args, CORE_ADDR sp,
function_call_return_method return_method,
CORE_ADDR struct_addr)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
int i, offset = 0;
CORE_ADDR gp;
/* "The outgoing parameter area [...] must be aligned at a 16-byte
boundary." */
sp = align_up (sp, 16);
for (i = 0; i < nargs; i++)
{
struct value *arg = args[i];
struct type *type = value_type (arg);
int len = TYPE_LENGTH (type);
const bfd_byte *valbuf;
bfd_byte fptrbuf[8];
int regnum;
/* "Each parameter begins on a 64-bit (8-byte) boundary." */
offset = align_up (offset, 8);
if (hppa64_integral_or_pointer_p (type))
{
/* "Integral scalar parameters smaller than 64 bits are
padded on the left (i.e., the value is in the
least-significant bits of the 64-bit storage unit, and
the high-order bits are undefined)." Therefore we can
safely sign-extend them. */
if (len < 8)
{
arg = value_cast (builtin_type (gdbarch)->builtin_int64, arg);
len = 8;
}
}
else if (hppa64_floating_p (type))
{
if (len > 8)
{
/* "Quad-precision (128-bit) floating-point scalar
parameters are aligned on a 16-byte boundary." */
offset = align_up (offset, 16);
/* "Double-extended- and quad-precision floating-point
parameters within the first 64 bytes of the parameter
list are always passed in general registers." */
}
else
{
if (len == 4)
{
/* "Single-precision (32-bit) floating-point scalar
parameters are padded on the left with 32 bits of
garbage (i.e., the floating-point value is in the
least-significant 32 bits of a 64-bit storage
unit)." */
offset += 4;
}
/* "Single- and double-precision floating-point
parameters in this area are passed according to the
available formal parameter information in a function
prototype. [...] If no prototype is in scope,
floating-point parameters must be passed both in the
corresponding general registers and in the
corresponding floating-point registers." */
regnum = HPPA64_FP4_REGNUM + offset / 8;
if (regnum < HPPA64_FP4_REGNUM + 8)
{
/* "Single-precision floating-point parameters, when
passed in floating-point registers, are passed in
the right halves of the floating point registers;
the left halves are unused." */
regcache->cooked_write_part (regnum, offset % 8, len,
value_contents (arg));
}
}
}
else
{
if (len > 8)
{
/* "Aggregates larger than 8 bytes are aligned on a
16-byte boundary, possibly leaving an unused argument
slot, which is filled with garbage. If necessary,
they are padded on the right (with garbage), to a
multiple of 8 bytes." */
offset = align_up (offset, 16);
}
}
/* If we are passing a function pointer, make sure we pass a function
descriptor instead of the function entry address. */
if (type->code () == TYPE_CODE_PTR
&& TYPE_TARGET_TYPE (type)->code () == TYPE_CODE_FUNC)
{
ULONGEST codeptr, fptr;
codeptr = unpack_long (type, value_contents (arg));
fptr = hppa64_convert_code_addr_to_fptr (gdbarch, codeptr);
store_unsigned_integer (fptrbuf, TYPE_LENGTH (type), byte_order,
fptr);
valbuf = fptrbuf;
}
else
{
valbuf = value_contents (arg);
}
/* Always store the argument in memory. */
write_memory (sp + offset, valbuf, len);
regnum = HPPA_ARG0_REGNUM - offset / 8;
while (regnum > HPPA_ARG0_REGNUM - 8 && len > 0)
{
regcache->cooked_write_part (regnum, offset % 8, std::min (len, 8),
valbuf);
offset += std::min (len, 8);
valbuf += std::min (len, 8);
len -= std::min (len, 8);
regnum--;
}
offset += len;
}
/* Set up GR29 (%ret1) to hold the argument pointer (ap). */
regcache_cooked_write_unsigned (regcache, HPPA_RET1_REGNUM, sp + 64);
/* Allocate the outgoing parameter area. Make sure the outgoing
parameter area is multiple of 16 bytes in length. */
sp += std::max (align_up (offset, 16), (ULONGEST) 64);
/* Allocate 32-bytes of scratch space. The documentation doesn't
mention this, but it seems to be needed. */
sp += 32;
/* Allocate the frame marker area. */
sp += 16;
/* If a structure has to be returned, set up GR 28 (%ret0) to hold
its address. */
if (return_method == return_method_struct)
regcache_cooked_write_unsigned (regcache, HPPA_RET0_REGNUM, struct_addr);
/* Set up GR27 (%dp) to hold the global pointer (gp). */
gp = tdep->find_global_pointer (gdbarch, function);
if (gp != 0)
regcache_cooked_write_unsigned (regcache, HPPA_DP_REGNUM, gp);
/* Set up GR2 (%rp) to hold the return pointer (rp). */
if (!gdbarch_push_dummy_code_p (gdbarch))
regcache_cooked_write_unsigned (regcache, HPPA_RP_REGNUM, bp_addr);
/* Set up GR30 to hold the stack pointer (sp). */
regcache_cooked_write_unsigned (regcache, HPPA_SP_REGNUM, sp);
return sp;
}
/* Handle 32/64-bit struct return conventions. */
static enum return_value_convention
hppa32_return_value (struct gdbarch *gdbarch, struct value *function,
struct type *type, struct regcache *regcache,
gdb_byte *readbuf, const gdb_byte *writebuf)
{
if (TYPE_LENGTH (type) <= 2 * 4)
{
/* The value always lives in the right hand end of the register
(or register pair)? */
int b;
int reg = type->code () == TYPE_CODE_FLT ? HPPA_FP4_REGNUM : 28;
int part = TYPE_LENGTH (type) % 4;
/* The left hand register contains only part of the value,
transfer that first so that the rest can be xfered as entire
4-byte registers. */
if (part > 0)
{
if (readbuf != NULL)
regcache->cooked_read_part (reg, 4 - part, part, readbuf);
if (writebuf != NULL)
regcache->cooked_write_part (reg, 4 - part, part, writebuf);
reg++;
}
/* Now transfer the remaining register values. */
for (b = part; b < TYPE_LENGTH (type); b += 4)
{
if (readbuf != NULL)
regcache->cooked_read (reg, readbuf + b);
if (writebuf != NULL)
regcache->cooked_write (reg, writebuf + b);
reg++;
}
return RETURN_VALUE_REGISTER_CONVENTION;
}
else
return RETURN_VALUE_STRUCT_CONVENTION;
}
static enum return_value_convention
hppa64_return_value (struct gdbarch *gdbarch, struct value *function,
struct type *type, struct regcache *regcache,
gdb_byte *readbuf, const gdb_byte *writebuf)
{
int len = TYPE_LENGTH (type);
int regnum, offset;
if (len > 16)
{
/* All return values larger than 128 bits must be aggregate
return values. */
gdb_assert (!hppa64_integral_or_pointer_p (type));
gdb_assert (!hppa64_floating_p (type));
/* "Aggregate return values larger than 128 bits are returned in
a buffer allocated by the caller. The address of the buffer
must be passed in GR 28." */
return RETURN_VALUE_STRUCT_CONVENTION;
}
if (hppa64_integral_or_pointer_p (type))
{
/* "Integral return values are returned in GR 28. Values
smaller than 64 bits are padded on the left (with garbage)." */
regnum = HPPA_RET0_REGNUM;
offset = 8 - len;
}
else if (hppa64_floating_p (type))
{
if (len > 8)
{
/* "Double-extended- and quad-precision floating-point
values are returned in GRs 28 and 29. The sign,
exponent, and most-significant bits of the mantissa are
returned in GR 28; the least-significant bits of the
mantissa are passed in GR 29. For double-extended
precision values, GR 29 is padded on the right with 48
bits of garbage." */
regnum = HPPA_RET0_REGNUM;
offset = 0;
}
else
{
/* "Single-precision and double-precision floating-point
return values are returned in FR 4R (single precision) or
FR 4 (double-precision)." */
regnum = HPPA64_FP4_REGNUM;
offset = 8 - len;
}
}
else
{
/* "Aggregate return values up to 64 bits in size are returned
in GR 28. Aggregates smaller than 64 bits are left aligned
in the register; the pad bits on the right are undefined."
"Aggregate return values between 65 and 128 bits are returned
in GRs 28 and 29. The first 64 bits are placed in GR 28, and
the remaining bits are placed, left aligned, in GR 29. The
pad bits on the right of GR 29 (if any) are undefined." */
regnum = HPPA_RET0_REGNUM;
offset = 0;
}
if (readbuf)
{
while (len > 0)
{
regcache->cooked_read_part (regnum, offset, std::min (len, 8),
readbuf);
readbuf += std::min (len, 8);
len -= std::min (len, 8);
regnum++;
}
}
if (writebuf)
{
while (len > 0)
{
regcache->cooked_write_part (regnum, offset, std::min (len, 8),
writebuf);
writebuf += std::min (len, 8);
len -= std::min (len, 8);
regnum++;
}
}
return RETURN_VALUE_REGISTER_CONVENTION;
}
static CORE_ADDR
hppa32_convert_from_func_ptr_addr (struct gdbarch *gdbarch, CORE_ADDR addr,
struct target_ops *targ)
{
if (addr & 2)
{
struct type *func_ptr_type = builtin_type (gdbarch)->builtin_func_ptr;
CORE_ADDR plabel = addr & ~3;
return read_memory_typed_address (plabel, func_ptr_type);
}
return addr;
}
static CORE_ADDR
hppa32_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr)
{
/* HP frames are 64-byte (or cache line) aligned (yes that's _byte_
and not _bit_)! */
return align_up (addr, 64);
}
/* Force all frames to 16-byte alignment. Better safe than sorry. */
static CORE_ADDR
hppa64_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr)
{
/* Just always 16-byte align. */
return align_up (addr, 16);
}
static CORE_ADDR
hppa_read_pc (readable_regcache *regcache)
{
ULONGEST ipsw;
ULONGEST pc;
regcache->cooked_read (HPPA_IPSW_REGNUM, &ipsw);
regcache->cooked_read (HPPA_PCOQ_HEAD_REGNUM, &pc);
/* If the current instruction is nullified, then we are effectively
still executing the previous instruction. Pretend we are still
there. This is needed when single stepping; if the nullified
instruction is on a different line, we don't want GDB to think
we've stepped onto that line. */
if (ipsw & 0x00200000)
pc -= 4;
return pc & ~0x3;
}
void
hppa_write_pc (struct regcache *regcache, CORE_ADDR pc)
{
regcache_cooked_write_unsigned (regcache, HPPA_PCOQ_HEAD_REGNUM, pc);
regcache_cooked_write_unsigned (regcache, HPPA_PCOQ_TAIL_REGNUM, pc + 4);
}
/* For the given instruction (INST), return any adjustment it makes
to the stack pointer or zero for no adjustment.
This only handles instructions commonly found in prologues. */
static int
prologue_inst_adjust_sp (unsigned long inst)
{
/* This must persist across calls. */
static int save_high21;
/* The most common way to perform a stack adjustment ldo X(sp),sp */
if ((inst & 0xffffc000) == 0x37de0000)
return hppa_extract_14 (inst);
/* stwm X,D(sp) */
if ((inst & 0xffe00000) == 0x6fc00000)
return hppa_extract_14 (inst);
/* std,ma X,D(sp) */
if ((inst & 0xffe00008) == 0x73c00008)
return (inst & 0x1 ? -(1 << 13) : 0) | (((inst >> 4) & 0x3ff) << 3);
/* addil high21,%r30; ldo low11,(%r1),%r30)
save high bits in save_high21 for later use. */
if ((inst & 0xffe00000) == 0x2bc00000)
{
save_high21 = hppa_extract_21 (inst);
return 0;
}
if ((inst & 0xffff0000) == 0x343e0000)
return save_high21 + hppa_extract_14 (inst);
/* fstws as used by the HP compilers. */
if ((inst & 0xffffffe0) == 0x2fd01220)
return hppa_extract_5_load (inst);
/* No adjustment. */
return 0;
}
/* Return nonzero if INST is a branch of some kind, else return zero. */
static int
is_branch (unsigned long inst)
{
switch (inst >> 26)
{
case 0x20:
case 0x21:
case 0x22:
case 0x23:
case 0x27:
case 0x28:
case 0x29:
case 0x2a:
case 0x2b:
case 0x2f:
case 0x30:
case 0x31:
case 0x32:
case 0x33:
case 0x38:
case 0x39:
case 0x3a:
case 0x3b:
return 1;
default:
return 0;
}
}
/* Return the register number for a GR which is saved by INST or
zero if INST does not save a GR.
Referenced from:
parisc 1.1:
https://parisc.wiki.kernel.org/images-parisc/6/68/Pa11_acd.pdf
parisc 2.0:
https://parisc.wiki.kernel.org/images-parisc/7/73/Parisc2.0.pdf
According to Table 6-5 of Chapter 6 (Memory Reference Instructions)
on page 106 in parisc 2.0, all instructions for storing values from
the general registers are:
Store: stb, sth, stw, std (according to Chapter 7, they
are only in both "inst >> 26" and "inst >> 6".
Store Absolute: stwa, stda (according to Chapter 7, they are only
in "inst >> 6".
Store Bytes: stby, stdby (according to Chapter 7, they are
only in "inst >> 6").
For (inst >> 26), according to Chapter 7:
The effective memory reference address is formed by the addition
of an immediate displacement to a base value.
- stb: 0x18, store a byte from a general register.
- sth: 0x19, store a halfword from a general register.
- stw: 0x1a, store a word from a general register.
- stwm: 0x1b, store a word from a general register and perform base
register modification (2.0 will still treat it as stw).
- std: 0x1c, store a doubleword from a general register (2.0 only).
- stw: 0x1f, store a word from a general register (2.0 only).
For (inst >> 6) when ((inst >> 26) == 0x03), according to Chapter 7:
The effective memory reference address is formed by the addition
of an index value to a base value specified in the instruction.
- stb: 0x08, store a byte from a general register (1.1 calls stbs).
- sth: 0x09, store a halfword from a general register (1.1 calls
sths).
- stw: 0x0a, store a word from a general register (1.1 calls stws).
- std: 0x0b: store a doubleword from a general register (2.0 only)
Implement fast byte moves (stores) to unaligned word or doubleword
destination.
- stby: 0x0c, for unaligned word (1.1 calls stbys).
- stdby: 0x0d for unaligned doubleword (2.0 only).
Store a word or doubleword using an absolute memory address formed
using short or long displacement or indexed
- stwa: 0x0e, store a word from a general register to an absolute
address (1.0 calls stwas).
- stda: 0x0f, store a doubleword from a general register to an
absolute address (2.0 only). */
static int
inst_saves_gr (unsigned long inst)
{
switch ((inst >> 26) & 0x0f)
{
case 0x03:
switch ((inst >> 6) & 0x0f)
{
case 0x08:
case 0x09:
case 0x0a:
case 0x0b:
case 0x0c:
case 0x0d:
case 0x0e:
case 0x0f:
return hppa_extract_5R_store (inst);
default:
return 0;
}
case 0x18:
case 0x19:
case 0x1a:
case 0x1b:
case 0x1c:
/* no 0x1d or 0x1e -- according to parisc 2.0 document */
case 0x1f:
return hppa_extract_5R_store (inst);
default:
return 0;
}
}
/* Return the register number for a FR which is saved by INST or
zero it INST does not save a FR.
Note we only care about full 64bit register stores (that's the only
kind of stores the prologue will use).
FIXME: What about argument stores with the HP compiler in ANSI mode? */
static int
inst_saves_fr (unsigned long inst)
{
/* Is this an FSTD? */
if ((inst & 0xfc00dfc0) == 0x2c001200)
return hppa_extract_5r_store (inst);
if ((inst & 0xfc000002) == 0x70000002)
return hppa_extract_5R_store (inst);
/* Is this an FSTW? */
if ((inst & 0xfc00df80) == 0x24001200)
return hppa_extract_5r_store (inst);
if ((inst & 0xfc000002) == 0x7c000000)
return hppa_extract_5R_store (inst);
return 0;
}
/* Advance PC across any function entry prologue instructions
to reach some "real" code.
Use information in the unwind table to determine what exactly should
be in the prologue. */
static CORE_ADDR
skip_prologue_hard_way (struct gdbarch *gdbarch, CORE_ADDR pc,
int stop_before_branch)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
gdb_byte buf[4];
CORE_ADDR orig_pc = pc;
unsigned long inst, stack_remaining, save_gr, save_fr, save_rp, save_sp;
unsigned long args_stored, status, i, restart_gr, restart_fr;
struct unwind_table_entry *u;
int final_iteration;
restart_gr = 0;
restart_fr = 0;
restart:
u = find_unwind_entry (pc);
if (!u)
return pc;
/* If we are not at the beginning of a function, then return now. */
if ((pc & ~0x3) != u->region_start)
return pc;
/* This is how much of a frame adjustment we need to account for. */
stack_remaining = u->Total_frame_size << 3;
/* Magic register saves we want to know about. */
save_rp = u->Save_RP;
save_sp = u->Save_SP;
/* An indication that args may be stored into the stack. Unfortunately
the HPUX compilers tend to set this in cases where no args were
stored too!. */
args_stored = 1;
/* Turn the Entry_GR field into a bitmask. */
save_gr = 0;
for (i = 3; i < u->Entry_GR + 3; i++)
{
/* Frame pointer gets saved into a special location. */
if (u->Save_SP && i == HPPA_FP_REGNUM)
continue;
save_gr |= (1 << i);
}
save_gr &= ~restart_gr;
/* Turn the Entry_FR field into a bitmask too. */
save_fr = 0;
for (i = 12; i < u->Entry_FR + 12; i++)
save_fr |= (1 << i);
save_fr &= ~restart_fr;
final_iteration = 0;
/* Loop until we find everything of interest or hit a branch.
For unoptimized GCC code and for any HP CC code this will never ever
examine any user instructions.
For optimized GCC code we're faced with problems. GCC will schedule
its prologue and make prologue instructions available for delay slot
filling. The end result is user code gets mixed in with the prologue
and a prologue instruction may be in the delay slot of the first branch
or call.
Some unexpected things are expected with debugging optimized code, so
we allow this routine to walk past user instructions in optimized
GCC code. */
while (save_gr || save_fr || save_rp || save_sp || stack_remaining > 0
|| args_stored)
{
unsigned int reg_num;
unsigned long old_stack_remaining, old_save_gr, old_save_fr;
unsigned long old_save_rp, old_save_sp, next_inst;
/* Save copies of all the triggers so we can compare them later
(only for HPC). */
old_save_gr = save_gr;
old_save_fr = save_fr;
old_save_rp = save_rp;
old_save_sp = save_sp;
old_stack_remaining = stack_remaining;
status = target_read_memory (pc, buf, 4);
inst = extract_unsigned_integer (buf, 4, byte_order);
/* Yow! */
if (status != 0)
return pc;
/* Note the interesting effects of this instruction. */
stack_remaining -= prologue_inst_adjust_sp (inst);
/* There are limited ways to store the return pointer into the
stack. */
if (inst == 0x6bc23fd9 || inst == 0x0fc212c1 || inst == 0x73c23fe1)
save_rp = 0;
/* These are the only ways we save SP into the stack. At this time
the HP compilers never bother to save SP into the stack. */
if ((inst & 0xffffc000) == 0x6fc10000
|| (inst & 0xffffc00c) == 0x73c10008)
save_sp = 0;
/* Are we loading some register with an offset from the argument
pointer? */
if ((inst & 0xffe00000) == 0x37a00000
|| (inst & 0xffffffe0) == 0x081d0240)
{
pc += 4;
continue;
}
/* Account for general and floating-point register saves. */
reg_num = inst_saves_gr (inst);
save_gr &= ~(1 << reg_num);
/* Ugh. Also account for argument stores into the stack.
Unfortunately args_stored only tells us that some arguments
where stored into the stack. Not how many or what kind!
This is a kludge as on the HP compiler sets this bit and it
never does prologue scheduling. So once we see one, skip past
all of them. We have similar code for the fp arg stores below.
FIXME. Can still die if we have a mix of GR and FR argument
stores! */
if (reg_num >= (gdbarch_ptr_bit (gdbarch) == 64 ? 19 : 23)
&& reg_num <= 26)
{
while (reg_num >= (gdbarch_ptr_bit (gdbarch) == 64 ? 19 : 23)
&& reg_num <= 26)
{
pc += 4;
status = target_read_memory (pc, buf, 4);
inst = extract_unsigned_integer (buf, 4, byte_order);
if (status != 0)
return pc;
reg_num = inst_saves_gr (inst);
}
args_stored = 0;
continue;
}
reg_num = inst_saves_fr (inst);
save_fr &= ~(1 << reg_num);
status = target_read_memory (pc + 4, buf, 4);
next_inst = extract_unsigned_integer (buf, 4, byte_order);
/* Yow! */
if (status != 0)
return pc;
/* We've got to be read to handle the ldo before the fp register
save. */
if ((inst & 0xfc000000) == 0x34000000
&& inst_saves_fr (next_inst) >= 4
&& inst_saves_fr (next_inst)
<= (gdbarch_ptr_bit (gdbarch) == 64 ? 11 : 7))
{
/* So we drop into the code below in a reasonable state. */
reg_num = inst_saves_fr (next_inst);
pc -= 4;
}
/* Ugh. Also account for argument stores into the stack.
This is a kludge as on the HP compiler sets this bit and it
never does prologue scheduling. So once we see one, skip past
all of them. */
if (reg_num >= 4
&& reg_num <= (gdbarch_ptr_bit (gdbarch) == 64 ? 11 : 7))
{
while (reg_num >= 4
&& reg_num
<= (gdbarch_ptr_bit (gdbarch) == 64 ? 11 : 7))
{
pc += 8;
status = target_read_memory (pc, buf, 4);
inst = extract_unsigned_integer (buf, 4, byte_order);
if (status != 0)
return pc;
if ((inst & 0xfc000000) != 0x34000000)
break;
status = target_read_memory (pc + 4, buf, 4);
next_inst = extract_unsigned_integer (buf, 4, byte_order);
if (status != 0)
return pc;
reg_num = inst_saves_fr (next_inst);
}
args_stored = 0;
continue;
}
/* Quit if we hit any kind of branch. This can happen if a prologue
instruction is in the delay slot of the first call/branch. */
if (is_branch (inst) && stop_before_branch)
break;
/* What a crock. The HP compilers set args_stored even if no
arguments were stored into the stack (boo hiss). This could
cause this code to then skip a bunch of user insns (up to the
first branch).
To combat this we try to identify when args_stored was bogusly
set and clear it. We only do this when args_stored is nonzero,
all other resources are accounted for, and nothing changed on
this pass. */
if (args_stored
&& !(save_gr || save_fr || save_rp || save_sp || stack_remaining > 0)
&& old_save_gr == save_gr && old_save_fr == save_fr
&& old_save_rp == save_rp && old_save_sp == save_sp
&& old_stack_remaining == stack_remaining)
break;
/* Bump the PC. */
pc += 4;
/* !stop_before_branch, so also look at the insn in the delay slot
of the branch. */
if (final_iteration)
break;
if (is_branch (inst))
final_iteration = 1;
}
/* We've got a tentative location for the end of the prologue. However
because of limitations in the unwind descriptor mechanism we may
have went too far into user code looking for the save of a register
that does not exist. So, if there registers we expected to be saved
but never were, mask them out and restart.
This should only happen in optimized code, and should be very rare. */
if (save_gr || (save_fr && !(restart_fr || restart_gr)))
{
pc = orig_pc;
restart_gr = save_gr;
restart_fr = save_fr;
goto restart;
}
return pc;
}
/* Return the address of the PC after the last prologue instruction if
we can determine it from the debug symbols. Else return zero. */
static CORE_ADDR
after_prologue (CORE_ADDR pc)
{
struct symtab_and_line sal;
CORE_ADDR func_addr, func_end;
/* If we can not find the symbol in the partial symbol table, then
there is no hope we can determine the function's start address
with this code. */
if (!find_pc_partial_function (pc, NULL, &func_addr, &func_end))
return 0;
/* Get the line associated with FUNC_ADDR. */
sal = find_pc_line (func_addr, 0);
/* There are only two cases to consider. First, the end of the source line
is within the function bounds. In that case we return the end of the
source line. Second is the end of the source line extends beyond the
bounds of the current function. We need to use the slow code to
examine instructions in that case.
Anything else is simply a bug elsewhere. Fixing it here is absolutely
the wrong thing to do. In fact, it should be entirely possible for this
function to always return zero since the slow instruction scanning code
is supposed to *always* work. If it does not, then it is a bug. */
if (sal.end < func_end)
return sal.end;
else
return 0;
}
/* To skip prologues, I use this predicate. Returns either PC itself
if the code at PC does not look like a function prologue; otherwise
returns an address that (if we're lucky) follows the prologue.
hppa_skip_prologue is called by gdb to place a breakpoint in a function.
It doesn't necessarily skips all the insns in the prologue. In fact
we might not want to skip all the insns because a prologue insn may
appear in the delay slot of the first branch, and we don't want to
skip over the branch in that case. */
static CORE_ADDR
hppa_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
{
CORE_ADDR post_prologue_pc;
/* See if we can determine the end of the prologue via the symbol table.
If so, then return either PC, or the PC after the prologue, whichever
is greater. */
post_prologue_pc = after_prologue (pc);
/* If after_prologue returned a useful address, then use it. Else
fall back on the instruction skipping code.
Some folks have claimed this causes problems because the breakpoint
may be the first instruction of the prologue. If that happens, then
the instruction skipping code has a bug that needs to be fixed. */
if (post_prologue_pc != 0)
return std::max (pc, post_prologue_pc);
else
return (skip_prologue_hard_way (gdbarch, pc, 1));
}
/* Return an unwind entry that falls within the frame's code block. */
static struct unwind_table_entry *
hppa_find_unwind_entry_in_block (struct frame_info *this_frame)
{
CORE_ADDR pc = get_frame_address_in_block (this_frame);
/* FIXME drow/20070101: Calling gdbarch_addr_bits_remove on the
result of get_frame_address_in_block implies a problem.
The bits should have been removed earlier, before the return
value of gdbarch_unwind_pc. That might be happening already;
if it isn't, it should be fixed. Then this call can be
removed. */
pc = gdbarch_addr_bits_remove (get_frame_arch (this_frame), pc);
return find_unwind_entry (pc);
}
struct hppa_frame_cache
{
CORE_ADDR base;
trad_frame_saved_reg *saved_regs;
};
static struct hppa_frame_cache *
hppa_frame_cache (struct frame_info *this_frame, void **this_cache)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
int word_size = gdbarch_ptr_bit (gdbarch) / 8;
struct hppa_frame_cache *cache;
long saved_gr_mask;
long saved_fr_mask;
long frame_size;
struct unwind_table_entry *u;
CORE_ADDR prologue_end;
int fp_in_r1 = 0;
int i;
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, "{ hppa_frame_cache (frame=%d) -> ",
frame_relative_level(this_frame));
if ((*this_cache) != NULL)
{
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, "base=%s (cached) }",
paddress (gdbarch, ((struct hppa_frame_cache *)*this_cache)->base));
return (struct hppa_frame_cache *) (*this_cache);
}
cache = FRAME_OBSTACK_ZALLOC (struct hppa_frame_cache);
(*this_cache) = cache;
cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
/* Yow! */
u = hppa_find_unwind_entry_in_block (this_frame);
if (!u)
{
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, "base=NULL (no unwind entry) }");
return (struct hppa_frame_cache *) (*this_cache);
}
/* Turn the Entry_GR field into a bitmask. */
saved_gr_mask = 0;
for (i = 3; i < u->Entry_GR + 3; i++)
{
/* Frame pointer gets saved into a special location. */
if (u->Save_SP && i == HPPA_FP_REGNUM)
continue;
saved_gr_mask |= (1 << i);
}
/* Turn the Entry_FR field into a bitmask too. */
saved_fr_mask = 0;
for (i = 12; i < u->Entry_FR + 12; i++)
saved_fr_mask |= (1 << i);
/* Loop until we find everything of interest or hit a branch.
For unoptimized GCC code and for any HP CC code this will never ever
examine any user instructions.
For optimized GCC code we're faced with problems. GCC will schedule
its prologue and make prologue instructions available for delay slot
filling. The end result is user code gets mixed in with the prologue
and a prologue instruction may be in the delay slot of the first branch
or call.
Some unexpected things are expected with debugging optimized code, so
we allow this routine to walk past user instructions in optimized
GCC code. */
{
int final_iteration = 0;
CORE_ADDR pc, start_pc, end_pc;
int looking_for_sp = u->Save_SP;
int looking_for_rp = u->Save_RP;
int fp_loc = -1;
/* We have to use skip_prologue_hard_way instead of just
skip_prologue_using_sal, in case we stepped into a function without
symbol information. hppa_skip_prologue also bounds the returned
pc by the passed in pc, so it will not return a pc in the next
function.
We used to call hppa_skip_prologue to find the end of the prologue,
but if some non-prologue instructions get scheduled into the prologue,
and the program is compiled with debug information, the "easy" way
in hppa_skip_prologue will return a prologue end that is too early
for us to notice any potential frame adjustments. */
/* We used to use get_frame_func to locate the beginning of the
function to pass to skip_prologue. However, when objects are
compiled without debug symbols, get_frame_func can return the wrong
function (or 0). We can do better than that by using unwind records.
This only works if the Region_description of the unwind record
indicates that it includes the entry point of the function.
HP compilers sometimes generate unwind records for regions that
do not include the entry or exit point of a function. GNU tools
do not do this. */
if ((u->Region_description & 0x2) == 0)
start_pc = u->region_start;
else
start_pc = get_frame_func (this_frame);
prologue_end = skip_prologue_hard_way (gdbarch, start_pc, 0);
end_pc = get_frame_pc (this_frame);
if (prologue_end != 0 && end_pc > prologue_end)
end_pc = prologue_end;
frame_size = 0;
for (pc = start_pc;
((saved_gr_mask || saved_fr_mask
|| looking_for_sp || looking_for_rp
|| frame_size < (u->Total_frame_size << 3))
&& pc < end_pc);
pc += 4)
{
int reg;
gdb_byte buf4[4];
long inst;
if (!safe_frame_unwind_memory (this_frame, pc, buf4))
{
error (_("Cannot read instruction at %s."),
paddress (gdbarch, pc));
return (struct hppa_frame_cache *) (*this_cache);
}
inst = extract_unsigned_integer (buf4, sizeof buf4, byte_order);
/* Note the interesting effects of this instruction. */
frame_size += prologue_inst_adjust_sp (inst);
/* There are limited ways to store the return pointer into the
stack. */
if (inst == 0x6bc23fd9) /* stw rp,-0x14(sr0,sp) */
{
looking_for_rp = 0;
cache->saved_regs[HPPA_RP_REGNUM].set_addr (-20);
}
else if (inst == 0x6bc23fd1) /* stw rp,-0x18(sr0,sp) */
{
looking_for_rp = 0;
cache->saved_regs[HPPA_RP_REGNUM].set_addr (-24);
}
else if (inst == 0x0fc212c1
|| inst == 0x73c23fe1) /* std rp,-0x10(sr0,sp) */
{
looking_for_rp = 0;
cache->saved_regs[HPPA_RP_REGNUM].set_addr (-16);
}
/* Check to see if we saved SP into the stack. This also
happens to indicate the location of the saved frame
pointer. */
if ((inst & 0xffffc000) == 0x6fc10000 /* stw,ma r1,N(sr0,sp) */
|| (inst & 0xffffc00c) == 0x73c10008) /* std,ma r1,N(sr0,sp) */
{
looking_for_sp = 0;
cache->saved_regs[HPPA_FP_REGNUM].set_addr (0);
}
else if (inst == 0x08030241) /* copy %r3, %r1 */
{
fp_in_r1 = 1;
}
/* Account for general and floating-point register saves. */
reg = inst_saves_gr (inst);
if (reg >= 3 && reg <= 18
&& (!u->Save_SP || reg != HPPA_FP_REGNUM))
{
saved_gr_mask &= ~(1 << reg);
if ((inst >> 26) == 0x1b && hppa_extract_14 (inst) >= 0)
/* stwm with a positive displacement is a _post_
_modify_. */
cache->saved_regs[reg].set_addr (0);
else if ((inst & 0xfc00000c) == 0x70000008)
/* A std has explicit post_modify forms. */
cache->saved_regs[reg].set_addr (0);
else
{
CORE_ADDR offset;
if ((inst >> 26) == 0x1c)
offset = (inst & 0x1 ? -(1 << 13) : 0)
| (((inst >> 4) & 0x3ff) << 3);
else if ((inst >> 26) == 0x03)
offset = hppa_low_hppa_sign_extend (inst & 0x1f, 5);
else
offset = hppa_extract_14 (inst);
/* Handle code with and without frame pointers. */
if (u->Save_SP)
cache->saved_regs[reg].set_addr (offset);
else
cache->saved_regs[reg].set_addr ((u->Total_frame_size << 3)
+ offset);
}
}
/* GCC handles callee saved FP regs a little differently.
It emits an instruction to put the value of the start of
the FP store area into %r1. It then uses fstds,ma with a
basereg of %r1 for the stores.
HP CC emits them at the current stack pointer modifying the
stack pointer as it stores each register. */
/* ldo X(%r3),%r1 or ldo X(%r30),%r1. */
if ((inst & 0xffffc000) == 0x34610000
|| (inst & 0xffffc000) == 0x37c10000)
fp_loc = hppa_extract_14 (inst);
reg = inst_saves_fr (inst);
if (reg >= 12 && reg <= 21)
{
/* Note +4 braindamage below is necessary because the FP
status registers are internally 8 registers rather than
the expected 4 registers. */
saved_fr_mask &= ~(1 << reg);
if (fp_loc == -1)
{
/* 1st HP CC FP register store. After this
instruction we've set enough state that the GCC and
HPCC code are both handled in the same manner. */
cache->saved_regs[reg + HPPA_FP4_REGNUM + 4].set_addr (0);
fp_loc = 8;
}
else
{
cache->saved_regs[reg + HPPA_FP0_REGNUM + 4].set_addr (fp_loc);
fp_loc += 8;
}
}
/* Quit if we hit any kind of branch the previous iteration. */
if (final_iteration)
break;
/* We want to look precisely one instruction beyond the branch
if we have not found everything yet. */
if (is_branch (inst))
final_iteration = 1;
}
}
{
/* The frame base always represents the value of %sp at entry to
the current function (and is thus equivalent to the "saved"
stack pointer. */
CORE_ADDR this_sp = get_frame_register_unsigned (this_frame,
HPPA_SP_REGNUM);
CORE_ADDR fp;
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, " (this_sp=%s, pc=%s, "
"prologue_end=%s) ",
paddress (gdbarch, this_sp),
paddress (gdbarch, get_frame_pc (this_frame)),
paddress (gdbarch, prologue_end));
/* Check to see if a frame pointer is available, and use it for
frame unwinding if it is.
There are some situations where we need to rely on the frame
pointer to do stack unwinding. For example, if a function calls
alloca (), the stack pointer can get adjusted inside the body of
the function. In this case, the ABI requires that the compiler
maintain a frame pointer for the function.
The unwind record has a flag (alloca_frame) that indicates that
a function has a variable frame; unfortunately, gcc/binutils
does not set this flag. Instead, whenever a frame pointer is used
and saved on the stack, the Save_SP flag is set. We use this to
decide whether to use the frame pointer for unwinding.
TODO: For the HP compiler, maybe we should use the alloca_frame flag
instead of Save_SP. */
fp = get_frame_register_unsigned (this_frame, HPPA_FP_REGNUM);
if (u->alloca_frame)
fp -= u->Total_frame_size << 3;
if (get_frame_pc (this_frame) >= prologue_end
&& (u->Save_SP || u->alloca_frame) && fp != 0)
{
cache->base = fp;
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, " (base=%s) [frame pointer]",
paddress (gdbarch, cache->base));
}
else if (u->Save_SP
&& cache->saved_regs[HPPA_SP_REGNUM].is_addr ())
{
/* Both we're expecting the SP to be saved and the SP has been
saved. The entry SP value is saved at this frame's SP
address. */
cache->base = read_memory_integer (this_sp, word_size, byte_order);
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, " (base=%s) [saved]",
paddress (gdbarch, cache->base));
}
else
{
/* The prologue has been slowly allocating stack space. Adjust
the SP back. */
cache->base = this_sp - frame_size;
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, " (base=%s) [unwind adjust]",
paddress (gdbarch, cache->base));
}
cache->saved_regs[HPPA_SP_REGNUM].set_value (cache->base);
}
/* The PC is found in the "return register", "Millicode" uses "r31"
as the return register while normal code uses "rp". */
if (u->Millicode)
{
if (cache->saved_regs[31].is_addr ())
{
cache->saved_regs[HPPA_PCOQ_HEAD_REGNUM] = cache->saved_regs[31];
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, " (pc=r31) [stack] } ");
}
else
{
ULONGEST r31 = get_frame_register_unsigned (this_frame, 31);
cache->saved_regs[HPPA_PCOQ_HEAD_REGNUM].set_value (r31);
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, " (pc=r31) [frame] } ");
}
}
else
{
if (cache->saved_regs[HPPA_RP_REGNUM].is_addr ())
{
cache->saved_regs[HPPA_PCOQ_HEAD_REGNUM] =
cache->saved_regs[HPPA_RP_REGNUM];
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, " (pc=rp) [stack] } ");
}
else
{
ULONGEST rp = get_frame_register_unsigned (this_frame,
HPPA_RP_REGNUM);
cache->saved_regs[HPPA_PCOQ_HEAD_REGNUM].set_value (rp);
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, " (pc=rp) [frame] } ");
}
}
/* If Save_SP is set, then we expect the frame pointer to be saved in the
frame. However, there is a one-insn window where we haven't saved it
yet, but we've already clobbered it. Detect this case and fix it up.
The prologue sequence for frame-pointer functions is:
0: stw %rp, -20(%sp)
4: copy %r3, %r1
8: copy %sp, %r3
c: stw,ma %r1, XX(%sp)
So if we are at offset c, the r3 value that we want is not yet saved
on the stack, but it's been overwritten. The prologue analyzer will
set fp_in_r1 when it sees the copy insn so we know to get the value
from r1 instead. */
if (u->Save_SP && !cache->saved_regs[HPPA_FP_REGNUM].is_addr ()
&& fp_in_r1)
{
ULONGEST r1 = get_frame_register_unsigned (this_frame, 1);
cache->saved_regs[HPPA_FP_REGNUM].set_value (r1);
}
{
/* Convert all the offsets into addresses. */
int reg;
for (reg = 0; reg < gdbarch_num_regs (gdbarch); reg++)
{
if (cache->saved_regs[reg].is_addr ())
cache->saved_regs[reg].set_addr (cache->saved_regs[reg].addr ()
+ cache->base);
}
}
{
struct gdbarch_tdep *tdep;
tdep = gdbarch_tdep (gdbarch);
if (tdep->unwind_adjust_stub)
tdep->unwind_adjust_stub (this_frame, cache->base, cache->saved_regs);
}
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, "base=%s }",
paddress (gdbarch, ((struct hppa_frame_cache *)*this_cache)->base));
return (struct hppa_frame_cache *) (*this_cache);
}
static void
hppa_frame_this_id (struct frame_info *this_frame, void **this_cache,
struct frame_id *this_id)
{
struct hppa_frame_cache *info;
struct unwind_table_entry *u;
info = hppa_frame_cache (this_frame, this_cache);
u = hppa_find_unwind_entry_in_block (this_frame);
(*this_id) = frame_id_build (info->base, u->region_start);
}
static struct value *
hppa_frame_prev_register (struct frame_info *this_frame,
void **this_cache, int regnum)
{
struct hppa_frame_cache *info = hppa_frame_cache (this_frame, this_cache);
return hppa_frame_prev_register_helper (this_frame,
info->saved_regs, regnum);
}
static int
hppa_frame_unwind_sniffer (const struct frame_unwind *self,
struct frame_info *this_frame, void **this_cache)
{
if (hppa_find_unwind_entry_in_block (this_frame))
return 1;
return 0;
}
static const struct frame_unwind hppa_frame_unwind =
{
"hppa unwind table",
NORMAL_FRAME,
default_frame_unwind_stop_reason,
hppa_frame_this_id,
hppa_frame_prev_register,
NULL,
hppa_frame_unwind_sniffer
};
/* This is a generic fallback frame unwinder that kicks in if we fail all
the other ones. Normally we would expect the stub and regular unwinder
to work, but in some cases we might hit a function that just doesn't
have any unwind information available. In this case we try to do
unwinding solely based on code reading. This is obviously going to be
slow, so only use this as a last resort. Currently this will only
identify the stack and pc for the frame. */
static struct hppa_frame_cache *
hppa_fallback_frame_cache (struct frame_info *this_frame, void **this_cache)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
struct hppa_frame_cache *cache;
unsigned int frame_size = 0;
int found_rp = 0;
CORE_ADDR start_pc;
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog,
"{ hppa_fallback_frame_cache (frame=%d) -> ",
frame_relative_level (this_frame));
cache = FRAME_OBSTACK_ZALLOC (struct hppa_frame_cache);
(*this_cache) = cache;
cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
start_pc = get_frame_func (this_frame);
if (start_pc)
{
CORE_ADDR cur_pc = get_frame_pc (this_frame);
CORE_ADDR pc;
for (pc = start_pc; pc < cur_pc; pc += 4)
{
unsigned int insn;
insn = read_memory_unsigned_integer (pc, 4, byte_order);
frame_size += prologue_inst_adjust_sp (insn);
/* There are limited ways to store the return pointer into the
stack. */
if (insn == 0x6bc23fd9) /* stw rp,-0x14(sr0,sp) */
{
cache->saved_regs[HPPA_RP_REGNUM].set_addr (-20);
found_rp = 1;
}
else if (insn == 0x0fc212c1
|| insn == 0x73c23fe1) /* std rp,-0x10(sr0,sp) */
{
cache->saved_regs[HPPA_RP_REGNUM].set_addr (-16);
found_rp = 1;
}
}
}
if (hppa_debug)
fprintf_unfiltered (gdb_stdlog, " frame_size=%d, found_rp=%d }\n",
frame_size, found_rp);
cache->base = get_frame_register_unsigned (this_frame, HPPA_SP_REGNUM);
cache->base -= frame_size;
cache->saved_regs[HPPA_SP_REGNUM].set_value (cache->base);
if (cache->saved_regs[HPPA_RP_REGNUM].is_addr ())
{
cache->saved_regs[HPPA_RP_REGNUM].set_addr (cache->saved_regs[HPPA_RP_REGNUM].addr ()
+ cache->base);
cache->saved_regs[HPPA_PCOQ_HEAD_REGNUM] =
cache->saved_regs[HPPA_RP_REGNUM];
}
else
{
ULONGEST rp;
rp = get_frame_register_unsigned (this_frame, HPPA_RP_REGNUM);
cache->saved_regs[HPPA_PCOQ_HEAD_REGNUM].set_value (rp);
}
return cache;
}
static void
hppa_fallback_frame_this_id (struct frame_info *this_frame, void **this_cache,
struct frame_id *this_id)
{
struct hppa_frame_cache *info =
hppa_fallback_frame_cache (this_frame, this_cache);
(*this_id) = frame_id_build (info->base, get_frame_func (this_frame));
}
static struct value *
hppa_fallback_frame_prev_register (struct frame_info *this_frame,
void **this_cache, int regnum)
{
struct hppa_frame_cache *info
= hppa_fallback_frame_cache (this_frame, this_cache);
return hppa_frame_prev_register_helper (this_frame,
info->saved_regs, regnum);
}
static const struct frame_unwind hppa_fallback_frame_unwind =
{
"hppa prologue",
NORMAL_FRAME,
default_frame_unwind_stop_reason,
hppa_fallback_frame_this_id,
hppa_fallback_frame_prev_register,
NULL,
default_frame_sniffer
};
/* Stub frames, used for all kinds of call stubs. */
struct hppa_stub_unwind_cache
{
CORE_ADDR base;
trad_frame_saved_reg *saved_regs;
};
static struct hppa_stub_unwind_cache *
hppa_stub_frame_unwind_cache (struct frame_info *this_frame,
void **this_cache)
{
struct hppa_stub_unwind_cache *info;
if (*this_cache)
return (struct hppa_stub_unwind_cache *) *this_cache;
info = FRAME_OBSTACK_ZALLOC (struct hppa_stub_unwind_cache);
*this_cache = info;
info->saved_regs = trad_frame_alloc_saved_regs (this_frame);
info->base = get_frame_register_unsigned (this_frame, HPPA_SP_REGNUM);
/* By default we assume that stubs do not change the rp. */
info->saved_regs[HPPA_PCOQ_HEAD_REGNUM].set_realreg (HPPA_RP_REGNUM);
return info;
}
static void
hppa_stub_frame_this_id (struct frame_info *this_frame,
void **this_prologue_cache,
struct frame_id *this_id)
{
struct hppa_stub_unwind_cache *info
= hppa_stub_frame_unwind_cache (this_frame, this_prologue_cache);
if (info)
*this_id = frame_id_build (info->base, get_frame_func (this_frame));
}
static struct value *
hppa_stub_frame_prev_register (struct frame_info *this_frame,
void **this_prologue_cache, int regnum)
{
struct hppa_stub_unwind_cache *info
= hppa_stub_frame_unwind_cache (this_frame, this_prologue_cache);
if (info == NULL)
error (_("Requesting registers from null frame."));
return hppa_frame_prev_register_helper (this_frame,
info->saved_regs, regnum);
}
static int
hppa_stub_unwind_sniffer (const struct frame_unwind *self,
struct frame_info *this_frame,
void **this_cache)
{
CORE_ADDR pc = get_frame_address_in_block (this_frame);
struct gdbarch *gdbarch = get_frame_arch (this_frame);
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
if (pc == 0
|| (tdep->in_solib_call_trampoline != NULL
&& tdep->in_solib_call_trampoline (gdbarch, pc))
|| gdbarch_in_solib_return_trampoline (gdbarch, pc, NULL))
return 1;
return 0;
}
static const struct frame_unwind hppa_stub_frame_unwind = {
"hppa stub",
NORMAL_FRAME,
default_frame_unwind_stop_reason,
hppa_stub_frame_this_id,
hppa_stub_frame_prev_register,
NULL,
hppa_stub_unwind_sniffer
};
CORE_ADDR
hppa_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
{
ULONGEST ipsw;
CORE_ADDR pc;
ipsw = frame_unwind_register_unsigned (next_frame, HPPA_IPSW_REGNUM);
pc = frame_unwind_register_unsigned (next_frame, HPPA_PCOQ_HEAD_REGNUM);
/* If the current instruction is nullified, then we are effectively
still executing the previous instruction. Pretend we are still
there. This is needed when single stepping; if the nullified
instruction is on a different line, we don't want GDB to think
we've stepped onto that line. */
if (ipsw & 0x00200000)
pc -= 4;
return pc & ~0x3;
}
/* Return the minimal symbol whose name is NAME and stub type is STUB_TYPE.
Return NULL if no such symbol was found. */
struct bound_minimal_symbol
hppa_lookup_stub_minimal_symbol (const char *name,
enum unwind_stub_types stub_type)
{
struct bound_minimal_symbol result = { NULL, NULL };
for (objfile *objfile : current_program_space->objfiles ())
{
for (minimal_symbol *msym : objfile->msymbols ())
{
if (strcmp (msym->linkage_name (), name) == 0)
{
struct unwind_table_entry *u;
u = find_unwind_entry (MSYMBOL_VALUE (msym));
if (u != NULL && u->stub_unwind.stub_type == stub_type)
{
result.objfile = objfile;
result.minsym = msym;
return result;
}
}
}
}
return result;
}
static void
unwind_command (const char *exp, int from_tty)
{
CORE_ADDR address;
struct unwind_table_entry *u;
/* If we have an expression, evaluate it and use it as the address. */
if (exp != 0 && *exp != 0)
address = parse_and_eval_address (exp);
else
return;
u = find_unwind_entry (address);
if (!u)
{
printf_unfiltered ("Can't find unwind table entry for %s\n", exp);
return;
}
printf_unfiltered ("unwind_table_entry (%s):\n", host_address_to_string (u));
printf_unfiltered ("\tregion_start = %s\n", hex_string (u->region_start));
printf_unfiltered ("\tregion_end = %s\n", hex_string (u->region_end));
#define pif(FLD) if (u->FLD) printf_unfiltered (" "#FLD);
printf_unfiltered ("\n\tflags =");
pif (Cannot_unwind);
pif (Millicode);
pif (Millicode_save_sr0);
pif (Entry_SR);
pif (Args_stored);
pif (Variable_Frame);
pif (Separate_Package_Body);
pif (Frame_Extension_Millicode);
pif (Stack_Overflow_Check);
pif (Two_Instruction_SP_Increment);
pif (sr4export);
pif (cxx_info);
pif (cxx_try_catch);
pif (sched_entry_seq);
pif (Save_SP);
pif (Save_RP);
pif (Save_MRP_in_frame);
pif (save_r19);
pif (Cleanup_defined);
pif (MPE_XL_interrupt_marker);
pif (HP_UX_interrupt_marker);
pif (Large_frame);
pif (alloca_frame);
putchar_unfiltered ('\n');
#define pin(FLD) printf_unfiltered ("\t"#FLD" = 0x%x\n", u->FLD);
pin (Region_description);
pin (Entry_FR);
pin (Entry_GR);
pin (Total_frame_size);
if (u->stub_unwind.stub_type)
{
printf_unfiltered ("\tstub type = ");
switch (u->stub_unwind.stub_type)
{
case LONG_BRANCH:
printf_unfiltered ("long branch\n");
break;
case PARAMETER_RELOCATION:
printf_unfiltered ("parameter relocation\n");
break;
case EXPORT:
printf_unfiltered ("export\n");
break;
case IMPORT:
printf_unfiltered ("import\n");
break;
case IMPORT_SHLIB:
printf_unfiltered ("import shlib\n");
break;
default:
printf_unfiltered ("unknown (%d)\n", u->stub_unwind.stub_type);
}
}
}
/* Return the GDB type object for the "standard" data type of data in
register REGNUM. */
static struct type *
hppa32_register_type (struct gdbarch *gdbarch, int regnum)
{
if (regnum < HPPA_FP4_REGNUM)
return builtin_type (gdbarch)->builtin_uint32;
else
return builtin_type (gdbarch)->builtin_float;
}
static struct type *
hppa64_register_type (struct gdbarch *gdbarch, int regnum)
{
if (regnum < HPPA64_FP4_REGNUM)
return builtin_type (gdbarch)->builtin_uint64;
else
return builtin_type (gdbarch)->builtin_double;
}
/* Return non-zero if REGNUM is not a register available to the user
through ptrace/ttrace. */
static int
hppa32_cannot_store_register (struct gdbarch *gdbarch, int regnum)
{
return (regnum == 0
|| regnum == HPPA_PCSQ_HEAD_REGNUM
|| (regnum >= HPPA_PCSQ_TAIL_REGNUM && regnum < HPPA_IPSW_REGNUM)
|| (regnum > HPPA_IPSW_REGNUM && regnum < HPPA_FP4_REGNUM));
}
static int
hppa32_cannot_fetch_register (struct gdbarch *gdbarch, int regnum)
{
/* cr26 and cr27 are readable (but not writable) from userspace. */
if (regnum == HPPA_CR26_REGNUM || regnum == HPPA_CR27_REGNUM)
return 0;
else
return hppa32_cannot_store_register (gdbarch, regnum);
}
static int
hppa64_cannot_store_register (struct gdbarch *gdbarch, int regnum)
{
return (regnum == 0
|| regnum == HPPA_PCSQ_HEAD_REGNUM
|| (regnum >= HPPA_PCSQ_TAIL_REGNUM && regnum < HPPA_IPSW_REGNUM)
|| (regnum > HPPA_IPSW_REGNUM && regnum < HPPA64_FP4_REGNUM));
}
static int
hppa64_cannot_fetch_register (struct gdbarch *gdbarch, int regnum)
{
/* cr26 and cr27 are readable (but not writable) from userspace. */
if (regnum == HPPA_CR26_REGNUM || regnum == HPPA_CR27_REGNUM)
return 0;
else
return hppa64_cannot_store_register (gdbarch, regnum);
}
static CORE_ADDR
hppa_addr_bits_remove (struct gdbarch *gdbarch, CORE_ADDR addr)
{
/* The low two bits of the PC on the PA contain the privilege level.
Some genius implementing a (non-GCC) compiler apparently decided
this means that "addresses" in a text section therefore include a
privilege level, and thus symbol tables should contain these bits.
This seems like a bonehead thing to do--anyway, it seems to work
for our purposes to just ignore those bits. */
return (addr &= ~0x3);
}
/* Get the ARGIth function argument for the current function. */
static CORE_ADDR
hppa_fetch_pointer_argument (struct frame_info *frame, int argi,
struct type *type)
{
return get_frame_register_unsigned (frame, HPPA_R0_REGNUM + 26 - argi);
}
static enum register_status
hppa_pseudo_register_read (struct gdbarch *gdbarch, readable_regcache *regcache,
int regnum, gdb_byte *buf)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
ULONGEST tmp;
enum register_status status;
status = regcache->raw_read (regnum, &tmp);
if (status == REG_VALID)
{
if (regnum == HPPA_PCOQ_HEAD_REGNUM || regnum == HPPA_PCOQ_TAIL_REGNUM)
tmp &= ~0x3;
store_unsigned_integer (buf, sizeof tmp, byte_order, tmp);
}
return status;
}
static CORE_ADDR
hppa_find_global_pointer (struct gdbarch *gdbarch, struct value *function)
{
return 0;
}
struct value *
hppa_frame_prev_register_helper (struct frame_info *this_frame,
trad_frame_saved_reg saved_regs[],
int regnum)
{
struct gdbarch *arch = get_frame_arch (this_frame);
enum bfd_endian byte_order = gdbarch_byte_order (arch);
if (regnum == HPPA_PCOQ_TAIL_REGNUM)
{
int size = register_size (arch, HPPA_PCOQ_HEAD_REGNUM);
CORE_ADDR pc;
struct value *pcoq_val =
trad_frame_get_prev_register (this_frame, saved_regs,
HPPA_PCOQ_HEAD_REGNUM);
pc = extract_unsigned_integer (value_contents_all (pcoq_val),
size, byte_order);
return frame_unwind_got_constant (this_frame, regnum, pc + 4);
}
return trad_frame_get_prev_register (this_frame, saved_regs, regnum);
}
/* An instruction to match. */
struct insn_pattern
{
unsigned int data; /* See if it matches this.... */
unsigned int mask; /* ... with this mask. */
};
/* See bfd/elf32-hppa.c */
static struct insn_pattern hppa_long_branch_stub[] = {
/* ldil LR'xxx,%r1 */
{ 0x20200000, 0xffe00000 },
/* be,n RR'xxx(%sr4,%r1) */
{ 0xe0202002, 0xffe02002 },
{ 0, 0 }
};
static struct insn_pattern hppa_long_branch_pic_stub[] = {
/* b,l .+8, %r1 */
{ 0xe8200000, 0xffe00000 },
/* addil LR'xxx - ($PIC_pcrel$0 - 4), %r1 */
{ 0x28200000, 0xffe00000 },
/* be,n RR'xxxx - ($PIC_pcrel$0 - 8)(%sr4, %r1) */
{ 0xe0202002, 0xffe02002 },
{ 0, 0 }
};
static struct insn_pattern hppa_import_stub[] = {
/* addil LR'xxx, %dp */
{ 0x2b600000, 0xffe00000 },
/* ldw RR'xxx(%r1), %r21 */
{ 0x48350000, 0xffffb000 },
/* bv %r0(%r21) */
{ 0xeaa0c000, 0xffffffff },
/* ldw RR'xxx+4(%r1), %r19 */
{ 0x48330000, 0xffffb000 },
{ 0, 0 }
};
s