blob: c06561460326fbe39cfcc3087dd90e17c33031ad [file] [log] [blame]
/* dw2gencfi.c - Support for generating Dwarf2 CFI information.
Copyright (C) 2003-2021 Free Software Foundation, Inc.
Contributed by Michal Ludvig <mludvig@suse.cz>
This file is part of GAS, the GNU Assembler.
GAS 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, or (at your option)
any later version.
GAS 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 GAS; see the file COPYING. If not, write to the Free
Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
02110-1301, USA. */
#include "as.h"
#include "dw2gencfi.h"
#include "subsegs.h"
#include "dwarf2dbg.h"
#ifdef TARGET_USE_CFIPOP
/* By default, use difference expressions if DIFF_EXPR_OK is defined. */
#ifndef CFI_DIFF_EXPR_OK
# ifdef DIFF_EXPR_OK
# define CFI_DIFF_EXPR_OK 1
# else
# define CFI_DIFF_EXPR_OK 0
# endif
#endif
#ifndef CFI_DIFF_LSDA_OK
#define CFI_DIFF_LSDA_OK CFI_DIFF_EXPR_OK
#endif
#if CFI_DIFF_EXPR_OK == 1 && CFI_DIFF_LSDA_OK == 0
# error "CFI_DIFF_EXPR_OK should imply CFI_DIFF_LSDA_OK"
#endif
/* We re-use DWARF2_LINE_MIN_INSN_LENGTH for the code alignment field
of the CIE. Default to 1 if not otherwise specified. */
#ifndef DWARF2_LINE_MIN_INSN_LENGTH
#define DWARF2_LINE_MIN_INSN_LENGTH 1
#endif
/* By default, use 32-bit relocations from .eh_frame into .text. */
#ifndef DWARF2_FDE_RELOC_SIZE
#define DWARF2_FDE_RELOC_SIZE 4
#endif
/* By default, use a read-only .eh_frame section. */
#ifndef DWARF2_EH_FRAME_READ_ONLY
#define DWARF2_EH_FRAME_READ_ONLY SEC_READONLY
#endif
#ifndef EH_FRAME_ALIGNMENT
#define EH_FRAME_ALIGNMENT (bfd_get_arch_size (stdoutput) == 64 ? 3 : 2)
#endif
#ifndef tc_cfi_frame_initial_instructions
#define tc_cfi_frame_initial_instructions() ((void)0)
#endif
#ifndef tc_cfi_startproc
# define tc_cfi_startproc() ((void)0)
#endif
#ifndef tc_cfi_endproc
# define tc_cfi_endproc(fde) ((void) (fde))
#endif
#define EH_FRAME_LINKONCE (SUPPORT_FRAME_LINKONCE || compact_eh)
#ifndef DWARF2_FORMAT
#define DWARF2_FORMAT(SEC) dwarf2_format_32bit
#endif
#ifndef DWARF2_ADDR_SIZE
#define DWARF2_ADDR_SIZE(bfd) (bfd_arch_bits_per_address (bfd) / 8)
#endif
#if MULTIPLE_FRAME_SECTIONS
#define CUR_SEG(structp) structp->cur_seg
#define SET_CUR_SEG(structp, seg) structp->cur_seg = seg
#define HANDLED(structp) structp->handled
#define SET_HANDLED(structp, val) structp->handled = val
#else
#define CUR_SEG(structp) NULL
#define SET_CUR_SEG(structp, seg) (void) (0 && seg)
#define HANDLED(structp) 0
#define SET_HANDLED(structp, val) (void) (0 && val)
#endif
#ifndef tc_cfi_reloc_for_encoding
#define tc_cfi_reloc_for_encoding(e) BFD_RELOC_NONE
#endif
/* Private segment collection list. */
struct dwcfi_seg_list
{
segT seg;
int subseg;
char * seg_name;
};
#ifdef SUPPORT_COMPACT_EH
static bool compact_eh;
#else
#define compact_eh 0
#endif
static htab_t dwcfi_hash;
/* Emit a single byte into the current segment. */
static inline void
out_one (int byte)
{
FRAG_APPEND_1_CHAR (byte);
}
/* Emit a two-byte word into the current segment. */
static inline void
out_two (int data)
{
md_number_to_chars (frag_more (2), data, 2);
}
/* Emit a four byte word into the current segment. */
static inline void
out_four (int data)
{
md_number_to_chars (frag_more (4), data, 4);
}
/* Emit an unsigned "little-endian base 128" number. */
static void
out_uleb128 (addressT value)
{
output_leb128 (frag_more (sizeof_leb128 (value, 0)), value, 0);
}
/* Emit an unsigned "little-endian base 128" number. */
static void
out_sleb128 (offsetT value)
{
output_leb128 (frag_more (sizeof_leb128 (value, 1)), value, 1);
}
static unsigned int
encoding_size (unsigned char encoding)
{
if (encoding == DW_EH_PE_omit)
return 0;
switch (encoding & 0x7)
{
case 0:
return bfd_get_arch_size (stdoutput) == 64 ? 8 : 4;
case DW_EH_PE_udata2:
return 2;
case DW_EH_PE_udata4:
return 4;
case DW_EH_PE_udata8:
return 8;
default:
abort ();
}
}
/* Emit expression EXP in ENCODING. If EMIT_ENCODING is true, first
emit a byte containing ENCODING. */
static void
emit_expr_encoded (expressionS *exp, int encoding, bool emit_encoding)
{
unsigned int size = encoding_size (encoding);
bfd_reloc_code_real_type code;
if (encoding == DW_EH_PE_omit)
return;
if (emit_encoding)
out_one (encoding);
code = tc_cfi_reloc_for_encoding (encoding);
if (code != BFD_RELOC_NONE)
{
reloc_howto_type *howto = bfd_reloc_type_lookup (stdoutput, code);
char *p = frag_more (size);
gas_assert (size == (unsigned) howto->bitsize / 8);
md_number_to_chars (p, 0, size);
fix_new (frag_now, p - frag_now->fr_literal, size, exp->X_add_symbol,
exp->X_add_number, howto->pc_relative, code);
}
else if ((encoding & 0x70) == DW_EH_PE_pcrel)
{
#if CFI_DIFF_EXPR_OK
expressionS tmp = *exp;
tmp.X_op = O_subtract;
tmp.X_op_symbol = symbol_temp_new_now ();
emit_expr (&tmp, size);
#elif defined (tc_cfi_emit_pcrel_expr)
tc_cfi_emit_pcrel_expr (exp, size);
#else
abort ();
#endif
}
else
emit_expr (exp, size);
}
/* Build based on segment the derived .debug_...
segment name containing origin segment's postfix name part. */
static char *
get_debugseg_name (segT seg, const char *base_name)
{
const char * name;
const char * dollar;
const char * dot;
if (!seg)
return concat (base_name, NULL);
name = bfd_section_name (seg);
if (name == NULL || *name == 0)
return concat (base_name, NULL);
dollar = strchr (name, '$');
dot = strchr (name + 1, '.');
if (!dollar && !dot)
{
if (!strcmp (base_name, ".eh_frame_entry")
&& strcmp (name, ".text") != 0)
return concat (base_name, ".", name, NULL);
name = "";
}
else if (!dollar)
name = dot;
else if (!dot)
name = dollar;
else if (dot < dollar)
name = dot;
else
name = dollar;
return concat (base_name, name, NULL);
}
/* Allocate a dwcfi_seg_list structure. */
static struct dwcfi_seg_list *
alloc_debugseg_item (segT seg, int subseg, char *name)
{
struct dwcfi_seg_list *r;
r = (struct dwcfi_seg_list *)
xmalloc (sizeof (struct dwcfi_seg_list) + strlen (name));
r->seg = seg;
r->subseg = subseg;
r->seg_name = name;
return r;
}
static segT
is_now_linkonce_segment (void)
{
if (compact_eh)
return now_seg;
if ((bfd_section_flags (now_seg)
& (SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD
| SEC_LINK_DUPLICATES_ONE_ONLY | SEC_LINK_DUPLICATES_SAME_SIZE
| SEC_LINK_DUPLICATES_SAME_CONTENTS)) != 0)
return now_seg;
return NULL;
}
/* Generate debug... segment with same linkonce properties
of based segment. */
static segT
make_debug_seg (segT cseg, char *name, int sflags)
{
segT save_seg = now_seg;
int save_subseg = now_subseg;
segT r;
flagword flags;
r = subseg_new (name, 0);
/* Check if code segment is marked as linked once. */
if (!cseg)
flags = 0;
else
flags = (bfd_section_flags (cseg)
& (SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD
| SEC_LINK_DUPLICATES_ONE_ONLY | SEC_LINK_DUPLICATES_SAME_SIZE
| SEC_LINK_DUPLICATES_SAME_CONTENTS));
/* Add standard section flags. */
flags |= sflags;
/* Apply possibly linked once flags to new generated segment, too. */
if (!bfd_set_section_flags (r, flags))
as_bad (_("bfd_set_section_flags: %s"),
bfd_errmsg (bfd_get_error ()));
/* Restore to previous segment. */
if (save_seg != NULL)
subseg_set (save_seg, save_subseg);
return r;
}
static struct dwcfi_seg_list *
dwcfi_hash_find (char *name)
{
return (struct dwcfi_seg_list *) str_hash_find (dwcfi_hash, name);
}
static struct dwcfi_seg_list *
dwcfi_hash_find_or_make (segT cseg, const char *base_name, int flags)
{
struct dwcfi_seg_list *item;
char *name;
/* Initialize dwcfi_hash once. */
if (!dwcfi_hash)
dwcfi_hash = str_htab_create ();
name = get_debugseg_name (cseg, base_name);
item = dwcfi_hash_find (name);
if (!item)
{
item = alloc_debugseg_item (make_debug_seg (cseg, name, flags), 0, name);
str_hash_insert (dwcfi_hash, item->seg_name, item, 0);
}
else
free (name);
return item;
}
/* ??? Share this with dwarf2cfg.c. */
#ifndef TC_DWARF2_EMIT_OFFSET
#define TC_DWARF2_EMIT_OFFSET generic_dwarf2_emit_offset
/* Create an offset to .dwarf2_*. */
static void
generic_dwarf2_emit_offset (symbolS *symbol, unsigned int size)
{
expressionS exp;
exp.X_op = O_symbol;
exp.X_add_symbol = symbol;
exp.X_add_number = 0;
emit_expr (&exp, size);
}
#endif
struct cfi_escape_data
{
struct cfi_escape_data *next;
expressionS exp;
};
struct cie_entry
{
struct cie_entry *next;
#if MULTIPLE_FRAME_SECTIONS
segT cur_seg;
#endif
symbolS *start_address;
unsigned int return_column;
unsigned int signal_frame;
unsigned char fde_encoding;
unsigned char per_encoding;
unsigned char lsda_encoding;
expressionS personality;
#ifdef tc_cie_entry_extras
tc_cie_entry_extras
#endif
struct cfi_insn_data *first, *last;
};
/* List of FDE entries. */
struct fde_entry *all_fde_data;
static struct fde_entry **last_fde_data = &all_fde_data;
/* List of CIEs so that they could be reused. */
static struct cie_entry *cie_root;
/* Construct a new FDE structure and add it to the end of the fde list. */
static struct fde_entry *
alloc_fde_entry (void)
{
struct fde_entry *fde = XCNEW (struct fde_entry);
frchain_now->frch_cfi_data = XCNEW (struct frch_cfi_data);
frchain_now->frch_cfi_data->cur_fde_data = fde;
*last_fde_data = fde;
last_fde_data = &fde->next;
SET_CUR_SEG (fde, is_now_linkonce_segment ());
SET_HANDLED (fde, 0);
fde->last = &fde->data;
fde->return_column = DWARF2_DEFAULT_RETURN_COLUMN;
fde->per_encoding = DW_EH_PE_omit;
fde->lsda_encoding = DW_EH_PE_omit;
fde->eh_header_type = EH_COMPACT_UNKNOWN;
#ifdef tc_fde_entry_init_extra
tc_fde_entry_init_extra (fde)
#endif
return fde;
}
/* The following functions are available for a backend to construct its
own unwind information, usually from legacy unwind directives. */
/* Construct a new INSN structure and add it to the end of the insn list
for the currently active FDE. */
static bool cfi_sections_set = false;
static int cfi_sections = CFI_EMIT_eh_frame;
int all_cfi_sections = 0;
static struct fde_entry *last_fde;
static struct cfi_insn_data *
alloc_cfi_insn_data (void)
{
struct cfi_insn_data *insn = XCNEW (struct cfi_insn_data);
struct fde_entry *cur_fde_data = frchain_now->frch_cfi_data->cur_fde_data;
*cur_fde_data->last = insn;
cur_fde_data->last = &insn->next;
SET_CUR_SEG (insn, is_now_linkonce_segment ());
return insn;
}
/* Construct a new FDE structure that begins at LABEL. */
void
cfi_new_fde (symbolS *label)
{
struct fde_entry *fde = alloc_fde_entry ();
fde->start_address = label;
frchain_now->frch_cfi_data->last_address = label;
}
/* End the currently open FDE. */
void
cfi_end_fde (symbolS *label)
{
frchain_now->frch_cfi_data->cur_fde_data->end_address = label;
free (frchain_now->frch_cfi_data);
frchain_now->frch_cfi_data = NULL;
}
/* Set the return column for the current FDE. */
void
cfi_set_return_column (unsigned regno)
{
frchain_now->frch_cfi_data->cur_fde_data->return_column = regno;
}
void
cfi_set_sections (void)
{
frchain_now->frch_cfi_data->cur_fde_data->sections = all_cfi_sections;
cfi_sections_set = true;
}
/* Universal functions to store new instructions. */
static void
cfi_add_CFA_insn (int insn)
{
struct cfi_insn_data *insn_ptr = alloc_cfi_insn_data ();
insn_ptr->insn = insn;
}
static void
cfi_add_CFA_insn_reg (int insn, unsigned regno)
{
struct cfi_insn_data *insn_ptr = alloc_cfi_insn_data ();
insn_ptr->insn = insn;
insn_ptr->u.r = regno;
}
static void
cfi_add_CFA_insn_offset (int insn, offsetT offset)
{
struct cfi_insn_data *insn_ptr = alloc_cfi_insn_data ();
insn_ptr->insn = insn;
insn_ptr->u.i = offset;
}
static void
cfi_add_CFA_insn_reg_reg (int insn, unsigned reg1, unsigned reg2)
{
struct cfi_insn_data *insn_ptr = alloc_cfi_insn_data ();
insn_ptr->insn = insn;
insn_ptr->u.rr.reg1 = reg1;
insn_ptr->u.rr.reg2 = reg2;
}
static void
cfi_add_CFA_insn_reg_offset (int insn, unsigned regno, offsetT offset)
{
struct cfi_insn_data *insn_ptr = alloc_cfi_insn_data ();
insn_ptr->insn = insn;
insn_ptr->u.ri.reg = regno;
insn_ptr->u.ri.offset = offset;
}
/* Add a CFI insn to advance the PC from the last address to LABEL. */
void
cfi_add_advance_loc (symbolS *label)
{
struct cfi_insn_data *insn = alloc_cfi_insn_data ();
insn->insn = DW_CFA_advance_loc;
insn->u.ll.lab1 = frchain_now->frch_cfi_data->last_address;
insn->u.ll.lab2 = label;
frchain_now->frch_cfi_data->last_address = label;
}
/* Add a CFI insn to label the current position in the CFI segment. */
void
cfi_add_label (const char *name)
{
unsigned int len = strlen (name) + 1;
struct cfi_insn_data *insn = alloc_cfi_insn_data ();
insn->insn = CFI_label;
obstack_grow (&notes, name, len);
insn->u.sym_name = (char *) obstack_finish (&notes);
}
/* Add a DW_CFA_offset record to the CFI data. */
void
cfi_add_CFA_offset (unsigned regno, offsetT offset)
{
unsigned int abs_data_align;
gas_assert (DWARF2_CIE_DATA_ALIGNMENT != 0);
cfi_add_CFA_insn_reg_offset (DW_CFA_offset, regno, offset);
abs_data_align = (DWARF2_CIE_DATA_ALIGNMENT < 0
? -DWARF2_CIE_DATA_ALIGNMENT : DWARF2_CIE_DATA_ALIGNMENT);
if (offset % abs_data_align)
as_bad (_("register save offset not a multiple of %u"), abs_data_align);
}
/* Add a DW_CFA_val_offset record to the CFI data. */
void
cfi_add_CFA_val_offset (unsigned regno, offsetT offset)
{
unsigned int abs_data_align;
gas_assert (DWARF2_CIE_DATA_ALIGNMENT != 0);
cfi_add_CFA_insn_reg_offset (DW_CFA_val_offset, regno, offset);
abs_data_align = (DWARF2_CIE_DATA_ALIGNMENT < 0
? -DWARF2_CIE_DATA_ALIGNMENT : DWARF2_CIE_DATA_ALIGNMENT);
if (offset % abs_data_align)
as_bad (_("register save offset not a multiple of %u"), abs_data_align);
}
/* Add a DW_CFA_def_cfa record to the CFI data. */
void
cfi_add_CFA_def_cfa (unsigned regno, offsetT offset)
{
cfi_add_CFA_insn_reg_offset (DW_CFA_def_cfa, regno, offset);
frchain_now->frch_cfi_data->cur_cfa_offset = offset;
}
/* Add a DW_CFA_register record to the CFI data. */
void
cfi_add_CFA_register (unsigned reg1, unsigned reg2)
{
cfi_add_CFA_insn_reg_reg (DW_CFA_register, reg1, reg2);
}
/* Add a DW_CFA_def_cfa_register record to the CFI data. */
void
cfi_add_CFA_def_cfa_register (unsigned regno)
{
cfi_add_CFA_insn_reg (DW_CFA_def_cfa_register, regno);
}
/* Add a DW_CFA_def_cfa_offset record to the CFI data. */
void
cfi_add_CFA_def_cfa_offset (offsetT offset)
{
cfi_add_CFA_insn_offset (DW_CFA_def_cfa_offset, offset);
frchain_now->frch_cfi_data->cur_cfa_offset = offset;
}
void
cfi_add_CFA_restore (unsigned regno)
{
cfi_add_CFA_insn_reg (DW_CFA_restore, regno);
}
void
cfi_add_CFA_undefined (unsigned regno)
{
cfi_add_CFA_insn_reg (DW_CFA_undefined, regno);
}
void
cfi_add_CFA_same_value (unsigned regno)
{
cfi_add_CFA_insn_reg (DW_CFA_same_value, regno);
}
void
cfi_add_CFA_remember_state (void)
{
struct cfa_save_data *p;
cfi_add_CFA_insn (DW_CFA_remember_state);
p = XNEW (struct cfa_save_data);
p->cfa_offset = frchain_now->frch_cfi_data->cur_cfa_offset;
p->next = frchain_now->frch_cfi_data->cfa_save_stack;
frchain_now->frch_cfi_data->cfa_save_stack = p;
}
void
cfi_add_CFA_restore_state (void)
{
struct cfa_save_data *p;
cfi_add_CFA_insn (DW_CFA_restore_state);
p = frchain_now->frch_cfi_data->cfa_save_stack;
if (p)
{
frchain_now->frch_cfi_data->cur_cfa_offset = p->cfa_offset;
frchain_now->frch_cfi_data->cfa_save_stack = p->next;
free (p);
}
else
as_bad (_("CFI state restore without previous remember"));
}
/* Parse CFI assembler directives. */
static void dot_cfi (int);
static void dot_cfi_escape (int);
static void dot_cfi_sections (int);
static void dot_cfi_startproc (int);
static void dot_cfi_endproc (int);
static void dot_cfi_fde_data (int);
static void dot_cfi_personality (int);
static void dot_cfi_personality_id (int);
static void dot_cfi_lsda (int);
static void dot_cfi_val_encoded_addr (int);
static void dot_cfi_inline_lsda (int);
static void dot_cfi_label (int);
const pseudo_typeS cfi_pseudo_table[] =
{
{ "cfi_sections", dot_cfi_sections, 0 },
{ "cfi_startproc", dot_cfi_startproc, 0 },
{ "cfi_endproc", dot_cfi_endproc, 0 },
{ "cfi_fde_data", dot_cfi_fde_data, 0 },
{ "cfi_def_cfa", dot_cfi, DW_CFA_def_cfa },
{ "cfi_def_cfa_register", dot_cfi, DW_CFA_def_cfa_register },
{ "cfi_def_cfa_offset", dot_cfi, DW_CFA_def_cfa_offset },
{ "cfi_adjust_cfa_offset", dot_cfi, CFI_adjust_cfa_offset },
{ "cfi_offset", dot_cfi, DW_CFA_offset },
{ "cfi_rel_offset", dot_cfi, CFI_rel_offset },
{ "cfi_register", dot_cfi, DW_CFA_register },
{ "cfi_return_column", dot_cfi, CFI_return_column },
{ "cfi_restore", dot_cfi, DW_CFA_restore },
{ "cfi_undefined", dot_cfi, DW_CFA_undefined },
{ "cfi_same_value", dot_cfi, DW_CFA_same_value },
{ "cfi_remember_state", dot_cfi, DW_CFA_remember_state },
{ "cfi_restore_state", dot_cfi, DW_CFA_restore_state },
{ "cfi_window_save", dot_cfi, DW_CFA_GNU_window_save },
{ "cfi_negate_ra_state", dot_cfi, DW_CFA_AARCH64_negate_ra_state },
{ "cfi_escape", dot_cfi_escape, 0 },
{ "cfi_signal_frame", dot_cfi, CFI_signal_frame },
{ "cfi_personality", dot_cfi_personality, 0 },
{ "cfi_personality_id", dot_cfi_personality_id, 0 },
{ "cfi_lsda", dot_cfi_lsda, 0 },
{ "cfi_val_encoded_addr", dot_cfi_val_encoded_addr, 0 },
{ "cfi_inline_lsda", dot_cfi_inline_lsda, 0 },
{ "cfi_label", dot_cfi_label, 0 },
{ "cfi_val_offset", dot_cfi, DW_CFA_val_offset },
{ NULL, NULL, 0 }
};
static void
cfi_parse_separator (void)
{
SKIP_WHITESPACE ();
if (*input_line_pointer == ',')
input_line_pointer++;
else
as_bad (_("missing separator"));
}
#ifndef tc_parse_to_dw2regnum
static void
tc_parse_to_dw2regnum (expressionS *exp)
{
# ifdef tc_regname_to_dw2regnum
SKIP_WHITESPACE ();
if (is_name_beginner (*input_line_pointer)
|| (*input_line_pointer == '%'
&& is_name_beginner (*++input_line_pointer)))
{
char *name, c;
c = get_symbol_name (& name);
exp->X_op = O_constant;
exp->X_add_number = tc_regname_to_dw2regnum (name);
restore_line_pointer (c);
}
else
# endif
expression_and_evaluate (exp);
}
#endif
static unsigned
cfi_parse_reg (void)
{
int regno;
expressionS exp;
tc_parse_to_dw2regnum (&exp);
switch (exp.X_op)
{
case O_register:
case O_constant:
regno = exp.X_add_number;
break;
default:
regno = -1;
break;
}
if (regno < 0)
{
as_bad (_("bad register expression"));
regno = 0;
}
return regno;
}
static offsetT
cfi_parse_const (void)
{
return get_absolute_expression ();
}
static void
dot_cfi (int arg)
{
offsetT offset;
unsigned reg1, reg2;
if (frchain_now->frch_cfi_data == NULL)
{
as_bad (_("CFI instruction used without previous .cfi_startproc"));
ignore_rest_of_line ();
return;
}
/* If the last address was not at the current PC, advance to current. */
if (symbol_get_frag (frchain_now->frch_cfi_data->last_address) != frag_now
|| (S_GET_VALUE (frchain_now->frch_cfi_data->last_address)
!= frag_now_fix ()))
cfi_add_advance_loc (symbol_temp_new_now ());
switch (arg)
{
case DW_CFA_offset:
reg1 = cfi_parse_reg ();
cfi_parse_separator ();
offset = cfi_parse_const ();
cfi_add_CFA_offset (reg1, offset);
break;
case DW_CFA_val_offset:
reg1 = cfi_parse_reg ();
cfi_parse_separator ();
offset = cfi_parse_const ();
cfi_add_CFA_val_offset (reg1, offset);
break;
case CFI_rel_offset:
reg1 = cfi_parse_reg ();
cfi_parse_separator ();
offset = cfi_parse_const ();
cfi_add_CFA_offset (reg1,
offset - frchain_now->frch_cfi_data->cur_cfa_offset);
break;
case DW_CFA_def_cfa:
reg1 = cfi_parse_reg ();
cfi_parse_separator ();
offset = cfi_parse_const ();
cfi_add_CFA_def_cfa (reg1, offset);
break;
case DW_CFA_register:
reg1 = cfi_parse_reg ();
cfi_parse_separator ();
reg2 = cfi_parse_reg ();
cfi_add_CFA_register (reg1, reg2);
break;
case DW_CFA_def_cfa_register:
reg1 = cfi_parse_reg ();
cfi_add_CFA_def_cfa_register (reg1);
break;
case DW_CFA_def_cfa_offset:
offset = cfi_parse_const ();
cfi_add_CFA_def_cfa_offset (offset);
break;
case CFI_adjust_cfa_offset:
offset = cfi_parse_const ();
cfi_add_CFA_def_cfa_offset (frchain_now->frch_cfi_data->cur_cfa_offset
+ offset);
break;
case DW_CFA_restore:
for (;;)
{
reg1 = cfi_parse_reg ();
cfi_add_CFA_restore (reg1);
SKIP_WHITESPACE ();
if (*input_line_pointer != ',')
break;
++input_line_pointer;
}
break;
case DW_CFA_undefined:
for (;;)
{
reg1 = cfi_parse_reg ();
cfi_add_CFA_undefined (reg1);
SKIP_WHITESPACE ();
if (*input_line_pointer != ',')
break;
++input_line_pointer;
}
break;
case DW_CFA_same_value:
reg1 = cfi_parse_reg ();
cfi_add_CFA_same_value (reg1);
break;
case CFI_return_column:
reg1 = cfi_parse_reg ();
cfi_set_return_column (reg1);
break;
case DW_CFA_remember_state:
cfi_add_CFA_remember_state ();
break;
case DW_CFA_restore_state:
cfi_add_CFA_restore_state ();
break;
case DW_CFA_GNU_window_save:
cfi_add_CFA_insn (DW_CFA_GNU_window_save);
break;
case CFI_signal_frame:
frchain_now->frch_cfi_data->cur_fde_data->signal_frame = 1;
break;
default:
abort ();
}
demand_empty_rest_of_line ();
}
static void
dot_cfi_escape (int ignored ATTRIBUTE_UNUSED)
{
struct cfi_escape_data *head, **tail, *e;
struct cfi_insn_data *insn;
if (frchain_now->frch_cfi_data == NULL)
{
as_bad (_("CFI instruction used without previous .cfi_startproc"));
ignore_rest_of_line ();
return;
}
/* If the last address was not at the current PC, advance to current. */
if (symbol_get_frag (frchain_now->frch_cfi_data->last_address) != frag_now
|| (S_GET_VALUE (frchain_now->frch_cfi_data->last_address)
!= frag_now_fix ()))
cfi_add_advance_loc (symbol_temp_new_now ());
tail = &head;
do
{
e = XNEW (struct cfi_escape_data);
do_parse_cons_expression (&e->exp, 1);
*tail = e;
tail = &e->next;
}
while (*input_line_pointer++ == ',');
*tail = NULL;
insn = alloc_cfi_insn_data ();
insn->insn = CFI_escape;
insn->u.esc = head;
--input_line_pointer;
demand_empty_rest_of_line ();
}
static void
dot_cfi_personality (int ignored ATTRIBUTE_UNUSED)
{
struct fde_entry *fde;
offsetT encoding;
if (frchain_now->frch_cfi_data == NULL)
{
as_bad (_("CFI instruction used without previous .cfi_startproc"));
ignore_rest_of_line ();
return;
}
fde = frchain_now->frch_cfi_data->cur_fde_data;
encoding = cfi_parse_const ();
if (encoding == DW_EH_PE_omit)
{
demand_empty_rest_of_line ();
fde->per_encoding = encoding;
return;
}
if ((encoding & 0xff) != encoding
|| ((((encoding & 0x70) != 0
#if CFI_DIFF_EXPR_OK || defined tc_cfi_emit_pcrel_expr
&& (encoding & 0x70) != DW_EH_PE_pcrel
#endif
)
/* leb128 can be handled, but does something actually need it? */
|| (encoding & 7) == DW_EH_PE_uleb128
|| (encoding & 7) > DW_EH_PE_udata8)
&& tc_cfi_reloc_for_encoding (encoding) == BFD_RELOC_NONE))
{
as_bad (_("invalid or unsupported encoding in .cfi_personality"));
ignore_rest_of_line ();
return;
}
if (*input_line_pointer++ != ',')
{
as_bad (_(".cfi_personality requires encoding and symbol arguments"));
ignore_rest_of_line ();
return;
}
expression_and_evaluate (&fde->personality);
switch (fde->personality.X_op)
{
case O_symbol:
break;
case O_constant:
if ((encoding & 0x70) == DW_EH_PE_pcrel)
encoding = DW_EH_PE_omit;
break;
default:
encoding = DW_EH_PE_omit;
break;
}
fde->per_encoding = encoding;
if (encoding == DW_EH_PE_omit)
{
as_bad (_("wrong second argument to .cfi_personality"));
ignore_rest_of_line ();
return;
}
demand_empty_rest_of_line ();
}
static void
dot_cfi_lsda (int ignored ATTRIBUTE_UNUSED)
{
struct fde_entry *fde;
offsetT encoding;
if (frchain_now->frch_cfi_data == NULL)
{
as_bad (_("CFI instruction used without previous .cfi_startproc"));
ignore_rest_of_line ();
return;
}
fde = frchain_now->frch_cfi_data->cur_fde_data;
encoding = cfi_parse_const ();
if (encoding == DW_EH_PE_omit)
{
demand_empty_rest_of_line ();
fde->lsda_encoding = encoding;
return;
}
if ((encoding & 0xff) != encoding
|| ((((encoding & 0x70) != 0
#if CFI_DIFF_LSDA_OK || defined tc_cfi_emit_pcrel_expr
&& (encoding & 0x70) != DW_EH_PE_pcrel
#endif
)
/* leb128 can be handled, but does something actually need it? */
|| (encoding & 7) == DW_EH_PE_uleb128
|| (encoding & 7) > DW_EH_PE_udata8)
&& tc_cfi_reloc_for_encoding (encoding) == BFD_RELOC_NONE))
{
as_bad (_("invalid or unsupported encoding in .cfi_lsda"));
ignore_rest_of_line ();
return;
}
if (*input_line_pointer++ != ',')
{
as_bad (_(".cfi_lsda requires encoding and symbol arguments"));
ignore_rest_of_line ();
return;
}
fde->lsda_encoding = encoding;
expression_and_evaluate (&fde->lsda);
switch (fde->lsda.X_op)
{
case O_symbol:
break;
case O_constant:
if ((encoding & 0x70) == DW_EH_PE_pcrel)
encoding = DW_EH_PE_omit;
break;
default:
encoding = DW_EH_PE_omit;
break;
}
fde->lsda_encoding = encoding;
if (encoding == DW_EH_PE_omit)
{
as_bad (_("wrong second argument to .cfi_lsda"));
ignore_rest_of_line ();
return;
}
demand_empty_rest_of_line ();
}
static void
dot_cfi_val_encoded_addr (int ignored ATTRIBUTE_UNUSED)
{
struct cfi_insn_data *insn_ptr;
offsetT encoding;
if (frchain_now->frch_cfi_data == NULL)
{
as_bad (_("CFI instruction used without previous .cfi_startproc"));
ignore_rest_of_line ();
return;
}
/* If the last address was not at the current PC, advance to current. */
if (symbol_get_frag (frchain_now->frch_cfi_data->last_address) != frag_now
|| (S_GET_VALUE (frchain_now->frch_cfi_data->last_address)
!= frag_now_fix ()))
cfi_add_advance_loc (symbol_temp_new_now ());
insn_ptr = alloc_cfi_insn_data ();
insn_ptr->insn = CFI_val_encoded_addr;
insn_ptr->u.ea.reg = cfi_parse_reg ();
cfi_parse_separator ();
encoding = cfi_parse_const ();
if ((encoding & 0xff) != encoding
|| ((encoding & 0x70) != 0
#if CFI_DIFF_EXPR_OK || defined tc_cfi_emit_pcrel_expr
&& (encoding & 0x70) != DW_EH_PE_pcrel
#endif
)
/* leb128 can be handled, but does something actually need it? */
|| (encoding & 7) == DW_EH_PE_uleb128
|| (encoding & 7) > DW_EH_PE_udata8)
{
as_bad (_("invalid or unsupported encoding in .cfi_lsda"));
encoding = DW_EH_PE_omit;
}
cfi_parse_separator ();
expression_and_evaluate (&insn_ptr->u.ea.exp);
switch (insn_ptr->u.ea.exp.X_op)
{
case O_symbol:
break;
case O_constant:
if ((encoding & 0x70) != DW_EH_PE_pcrel)
break;
/* Fall through. */
default:
encoding = DW_EH_PE_omit;
break;
}
insn_ptr->u.ea.encoding = encoding;
if (encoding == DW_EH_PE_omit)
{
as_bad (_("wrong third argument to .cfi_val_encoded_addr"));
ignore_rest_of_line ();
return;
}
demand_empty_rest_of_line ();
}
static void
dot_cfi_label (int ignored ATTRIBUTE_UNUSED)
{
char *name;
if (frchain_now->frch_cfi_data == NULL)
{
as_bad (_("CFI instruction used without previous .cfi_startproc"));
ignore_rest_of_line ();
return;
}
name = read_symbol_name ();
if (name == NULL)
return;
/* If the last address was not at the current PC, advance to current. */
if (symbol_get_frag (frchain_now->frch_cfi_data->last_address) != frag_now
|| (S_GET_VALUE (frchain_now->frch_cfi_data->last_address)
!= frag_now_fix ()))
cfi_add_advance_loc (symbol_temp_new_now ());
cfi_add_label (name);
free (name);
demand_empty_rest_of_line ();
}
static void
dot_cfi_sections (int ignored ATTRIBUTE_UNUSED)
{
int sections = 0;
SKIP_WHITESPACE ();
if (is_name_beginner (*input_line_pointer) || *input_line_pointer == '"')
while (1)
{
char * saved_ilp;
char *name, c;
saved_ilp = input_line_pointer;
c = get_symbol_name (& name);
if (startswith (name, ".eh_frame")
&& name[9] != '_')
sections |= CFI_EMIT_eh_frame;
else if (startswith (name, ".debug_frame"))
sections |= CFI_EMIT_debug_frame;
#if SUPPORT_COMPACT_EH
else if (startswith (name, ".eh_frame_entry"))
{
compact_eh = true;
sections |= CFI_EMIT_eh_frame_compact;
}
#endif
#ifdef tc_cfi_section_name
else if (strcmp (name, tc_cfi_section_name) == 0)
sections |= CFI_EMIT_target;
#endif
else
{
*input_line_pointer = c;
input_line_pointer = saved_ilp;
break;
}
*input_line_pointer = c;
SKIP_WHITESPACE_AFTER_NAME ();
if (*input_line_pointer == ',')
{
name = input_line_pointer++;
SKIP_WHITESPACE ();
if (!is_name_beginner (*input_line_pointer)
&& *input_line_pointer != '"')
{
input_line_pointer = name;
break;
}
}
else if (is_name_beginner (*input_line_pointer)
|| *input_line_pointer == '"')
break;
}
demand_empty_rest_of_line ();
if (cfi_sections_set
&& (sections & (CFI_EMIT_eh_frame | CFI_EMIT_eh_frame_compact))
&& ((cfi_sections & (CFI_EMIT_eh_frame | CFI_EMIT_eh_frame_compact))
!= (sections & (CFI_EMIT_eh_frame | CFI_EMIT_eh_frame_compact))))
as_bad (_("inconsistent uses of .cfi_sections"));
cfi_sections = sections;
}
static void
dot_cfi_startproc (int ignored ATTRIBUTE_UNUSED)
{
int simple = 0;
if (frchain_now->frch_cfi_data != NULL)
{
as_bad (_("previous CFI entry not closed (missing .cfi_endproc)"));
ignore_rest_of_line ();
return;
}
cfi_new_fde (symbol_temp_new_now ());
SKIP_WHITESPACE ();
if (is_name_beginner (*input_line_pointer) || *input_line_pointer == '"')
{
char * saved_ilp = input_line_pointer;
char *name, c;
c = get_symbol_name (& name);
if (strcmp (name, "simple") == 0)
{
simple = 1;
restore_line_pointer (c);
}
else
input_line_pointer = saved_ilp;
}
demand_empty_rest_of_line ();
cfi_sections_set = true;
all_cfi_sections |= cfi_sections;
cfi_set_sections ();
frchain_now->frch_cfi_data->cur_cfa_offset = 0;
if (!simple)
tc_cfi_frame_initial_instructions ();
if ((cfi_sections & CFI_EMIT_target) != 0)
tc_cfi_startproc ();
}
static void
dot_cfi_endproc (int ignored ATTRIBUTE_UNUSED)
{
if (frchain_now->frch_cfi_data == NULL)
{
as_bad (_(".cfi_endproc without corresponding .cfi_startproc"));
ignore_rest_of_line ();
return;
}
last_fde = frchain_now->frch_cfi_data->cur_fde_data;
cfi_end_fde (symbol_temp_new_now ());
demand_empty_rest_of_line ();
cfi_sections_set = true;
if ((cfi_sections & CFI_EMIT_target) != 0)
tc_cfi_endproc (last_fde);
}
static segT
get_cfi_seg (segT cseg, const char *base, flagword flags, int align)
{
/* Exclude .debug_frame sections for Compact EH. */
if (SUPPORT_FRAME_LINKONCE || ((flags & SEC_DEBUGGING) == 0 && compact_eh))
{
struct dwcfi_seg_list *l;
l = dwcfi_hash_find_or_make (cseg, base, flags);
cseg = l->seg;
subseg_set (cseg, l->subseg);
}
else
{
cseg = subseg_new (base, 0);
bfd_set_section_flags (cseg, flags);
}
record_alignment (cseg, align);
return cseg;
}
#if SUPPORT_COMPACT_EH
static void
dot_cfi_personality_id (int ignored ATTRIBUTE_UNUSED)
{
struct fde_entry *fde;
if (frchain_now->frch_cfi_data == NULL)
{
as_bad (_("CFI instruction used without previous .cfi_startproc"));
ignore_rest_of_line ();
return;
}
fde = frchain_now->frch_cfi_data->cur_fde_data;
fde->personality_id = cfi_parse_const ();
demand_empty_rest_of_line ();
if (fde->personality_id == 0 || fde->personality_id > 3)
{
as_bad (_("wrong argument to .cfi_personality_id"));
return;
}
}
static void
dot_cfi_fde_data (int ignored ATTRIBUTE_UNUSED)
{
if (frchain_now->frch_cfi_data == NULL)
{
as_bad (_(".cfi_fde_data without corresponding .cfi_startproc"));
ignore_rest_of_line ();
return;
}
last_fde = frchain_now->frch_cfi_data->cur_fde_data;
cfi_sections_set = true;
if ((cfi_sections & CFI_EMIT_target) != 0
|| (cfi_sections & CFI_EMIT_eh_frame_compact) != 0)
{
struct cfi_escape_data *head, **tail, *e;
int num_ops = 0;
tail = &head;
if (!is_it_end_of_statement ())
{
num_ops = 0;
do
{
e = XNEW (struct cfi_escape_data);
do_parse_cons_expression (&e->exp, 1);
*tail = e;
tail = &e->next;
num_ops++;
}
while (*input_line_pointer++ == ',');
--input_line_pointer;
}
*tail = NULL;
if (last_fde->lsda_encoding != DW_EH_PE_omit)
last_fde->eh_header_type = EH_COMPACT_HAS_LSDA;
else if (num_ops <= 3 && last_fde->per_encoding == DW_EH_PE_omit)
last_fde->eh_header_type = EH_COMPACT_INLINE;
else
last_fde->eh_header_type = EH_COMPACT_OUTLINE;
if (last_fde->eh_header_type == EH_COMPACT_INLINE)
num_ops = 3;
last_fde->eh_data_size = num_ops;
last_fde->eh_data = XNEWVEC (bfd_byte, num_ops);
num_ops = 0;
while (head)
{
e = head;
head = e->next;
last_fde->eh_data[num_ops++] = e->exp.X_add_number;
free (e);
}
if (last_fde->eh_header_type == EH_COMPACT_INLINE)
while (num_ops < 3)
last_fde->eh_data[num_ops++] = tc_compact_eh_opcode_stop;
}
demand_empty_rest_of_line ();
}
/* Function to emit the compact unwinding opcodes stored in the
fde's eh_data field. The end of the opcode data will be
padded to the value in align. */
static void
output_compact_unwind_data (struct fde_entry *fde, int align)
{
int data_size = fde->eh_data_size + 2;
int align_padding;
int amask;
char *p;
fde->eh_loc = symbol_temp_new_now ();
p = frag_more (1);
if (fde->personality_id != 0)
*p = fde->personality_id;
else if (fde->per_encoding != DW_EH_PE_omit)
{
*p = 0;
emit_expr_encoded (&fde->personality, fde->per_encoding, false);
data_size += encoding_size (fde->per_encoding);
}
else
*p = 1;
amask = (1 << align) - 1;
align_padding = ((data_size + amask) & ~amask) - data_size;
p = frag_more (fde->eh_data_size + 1 + align_padding);
memcpy (p, fde->eh_data, fde->eh_data_size);
p += fde->eh_data_size;
while (align_padding-- > 0)
*(p++) = tc_compact_eh_opcode_pad;
*(p++) = tc_compact_eh_opcode_stop;
fde->eh_header_type = EH_COMPACT_OUTLINE_DONE;
}
/* Handle the .cfi_inline_lsda directive. */
static void
dot_cfi_inline_lsda (int ignored ATTRIBUTE_UNUSED)
{
segT ccseg;
int align;
long max_alignment = 28;
if (!last_fde)
{
as_bad (_("unexpected .cfi_inline_lsda"));
ignore_rest_of_line ();
return;
}
if ((last_fde->sections & CFI_EMIT_eh_frame_compact) == 0)
{
as_bad (_(".cfi_inline_lsda not valid for this frame"));
ignore_rest_of_line ();
return;
}
if (last_fde->eh_header_type != EH_COMPACT_UNKNOWN
&& last_fde->eh_header_type != EH_COMPACT_HAS_LSDA)
{
as_bad (_(".cfi_inline_lsda seen for frame without .cfi_lsda"));
ignore_rest_of_line ();
return;
}
#ifdef md_flush_pending_output
md_flush_pending_output ();
#endif
align = get_absolute_expression ();
if (align > max_alignment)
{
align = max_alignment;
as_bad (_("Alignment too large: %d. assumed."), align);
}
else if (align < 0)
{
as_warn (_("Alignment negative: 0 assumed."));
align = 0;
}
demand_empty_rest_of_line ();
ccseg = CUR_SEG (last_fde);
/* Open .gnu_extab section. */
get_cfi_seg (ccseg, ".gnu_extab",
(SEC_ALLOC | SEC_LOAD | SEC_DATA
| DWARF2_EH_FRAME_READ_ONLY),
1);
frag_align (align, 0, 0);
record_alignment (now_seg, align);
if (last_fde->eh_header_type == EH_COMPACT_HAS_LSDA)
output_compact_unwind_data (last_fde, align);
last_fde = NULL;
return;
}
#else /* !SUPPORT_COMPACT_EH */
static void
dot_cfi_inline_lsda (int ignored ATTRIBUTE_UNUSED)
{
as_bad (_(".cfi_inline_lsda is not supported for this target"));
ignore_rest_of_line ();
}
static void
dot_cfi_fde_data (int ignored ATTRIBUTE_UNUSED)
{
as_bad (_(".cfi_fde_data is not supported for this target"));
ignore_rest_of_line ();
}
static void
dot_cfi_personality_id (int ignored ATTRIBUTE_UNUSED)
{
as_bad (_(".cfi_personality_id is not supported for this target"));
ignore_rest_of_line ();
}
#endif
static void
output_cfi_insn (struct cfi_insn_data *insn)
{
offsetT offset;
unsigned int regno;
switch (insn->insn)
{
case DW_CFA_advance_loc:
{
symbolS *from = insn->u.ll.lab1;
symbolS *to = insn->u.ll.lab2;
if (symbol_get_frag (to) == symbol_get_frag (from))
{
addressT delta = S_GET_VALUE (to) - S_GET_VALUE (from);
addressT scaled = delta / DWARF2_LINE_MIN_INSN_LENGTH;
if (scaled == 0)
;
else if (scaled <= 0x3F)
out_one (DW_CFA_advance_loc + scaled);
else if (scaled <= 0xFF)
{
out_one (DW_CFA_advance_loc1);
out_one (scaled);
}
else if (scaled <= 0xFFFF)
{
out_one (DW_CFA_advance_loc2);
out_two (scaled);
}
else
{
out_one (DW_CFA_advance_loc4);
out_four (scaled);
}
}
else
{
expressionS exp;
exp.X_op = O_subtract;
exp.X_add_symbol = to;
exp.X_op_symbol = from;
exp.X_add_number = 0;
/* The code in ehopt.c expects that one byte of the encoding
is already allocated to the frag. This comes from the way
that it scans the .eh_frame section looking first for the
.byte DW_CFA_advance_loc4. Call frag_grow with the sum of
room needed by frag_more and frag_var to preallocate space
ensuring that the DW_CFA_advance_loc4 is in the fixed part
of the rs_cfa frag, so that the relax machinery can remove
the advance_loc should it advance by zero. */
frag_grow (5);
*frag_more (1) = DW_CFA_advance_loc4;
frag_var (rs_cfa, 4, 0, DWARF2_LINE_MIN_INSN_LENGTH << 3,
make_expr_symbol (&exp), frag_now_fix () - 1,
(char *) frag_now);
}
}
break;
case DW_CFA_def_cfa:
offset = insn->u.ri.offset;
if (offset < 0)
{
out_one (DW_CFA_def_cfa_sf);
out_uleb128 (insn->u.ri.reg);
out_sleb128 (offset / DWARF2_CIE_DATA_ALIGNMENT);
}
else
{
out_one (DW_CFA_def_cfa);
out_uleb128 (insn->u.ri.reg);
out_uleb128 (offset);
}
break;
case DW_CFA_def_cfa_register:
case DW_CFA_undefined:
case DW_CFA_same_value:
out_one (insn->insn);
out_uleb128 (insn->u.r);
break;
case DW_CFA_def_cfa_offset:
offset = insn->u.i;
if (offset < 0)
{
out_one (DW_CFA_def_cfa_offset_sf);
out_sleb128 (offset / DWARF2_CIE_DATA_ALIGNMENT);
}
else
{
out_one (DW_CFA_def_cfa_offset);
out_uleb128 (offset);
}
break;
case DW_CFA_restore:
regno = insn->u.r;
if (regno <= 0x3F)
{
out_one (DW_CFA_restore + regno);
}
else
{
out_one (DW_CFA_restore_extended);
out_uleb128 (regno);
}
break;
case DW_CFA_offset:
regno = insn->u.ri.reg;
offset = insn->u.ri.offset / DWARF2_CIE_DATA_ALIGNMENT;
if (offset < 0)
{
out_one (DW_CFA_offset_extended_sf);
out_uleb128 (regno);
out_sleb128 (offset);
}
else if (regno <= 0x3F)
{
out_one (DW_CFA_offset + regno);
out_uleb128 (offset);
}
else
{
out_one (DW_CFA_offset_extended);
out_uleb128 (regno);
out_uleb128 (offset);
}
break;
case DW_CFA_val_offset:
regno = insn->u.ri.reg;
offset = insn->u.ri.offset / DWARF2_CIE_DATA_ALIGNMENT;
if (offset < 0)
{
out_one (DW_CFA_val_offset_sf);
out_uleb128 (regno);
out_sleb128 (offset);
}
else
{
out_one (DW_CFA_val_offset);
out_uleb128 (regno);
out_uleb128 (offset);
}
break;
case DW_CFA_register:
out_one (DW_CFA_register);
out_uleb128 (insn->u.rr.reg1);
out_uleb128 (insn->u.rr.reg2);
break;
case DW_CFA_remember_state:
case DW_CFA_restore_state:
out_one (insn->insn);
break;
case DW_CFA_GNU_window_save:
out_one (DW_CFA_GNU_window_save);
break;
case CFI_escape:
{
struct cfi_escape_data *e;
for (e = insn->u.esc; e ; e = e->next)
emit_expr (&e->exp, 1);
break;
}
case CFI_val_encoded_addr:
{
unsigned encoding = insn->u.ea.encoding;
offsetT enc_size;
if (encoding == DW_EH_PE_omit)
break;
out_one (DW_CFA_val_expression);
out_uleb128 (insn->u.ea.reg);
switch (encoding & 0x7)
{
case DW_EH_PE_absptr:
enc_size = DWARF2_ADDR_SIZE (stdoutput);
break;
case DW_EH_PE_udata2:
enc_size = 2;
break;
case DW_EH_PE_udata4:
enc_size = 4;
break;
case DW_EH_PE_udata8:
enc_size = 8;
break;
default:
abort ();
}
/* If the user has requested absolute encoding,
then use the smaller DW_OP_addr encoding. */
if (insn->u.ea.encoding == DW_EH_PE_absptr)
{
out_uleb128 (1 + enc_size);
out_one (DW_OP_addr);
}
else
{
out_uleb128 (1 + 1 + enc_size);
out_one (DW_OP_GNU_encoded_addr);
out_one (encoding);
if ((encoding & 0x70) == DW_EH_PE_pcrel)
{
#if CFI_DIFF_EXPR_OK
insn->u.ea.exp.X_op = O_subtract;
insn->u.ea.exp.X_op_symbol = symbol_temp_new_now ();
#elif defined (tc_cfi_emit_pcrel_expr)
tc_cfi_emit_pcrel_expr (&insn->u.ea.exp, enc_size);
break;
#else
abort ();
#endif
}
}
emit_expr (&insn->u.ea.exp, enc_size);
}
break;
case CFI_label:
colon (insn->u.sym_name);
break;
default:
abort ();
}
}
static void
output_cie (struct cie_entry *cie, bool eh_frame, int align)
{
symbolS *after_size_address, *end_address;
expressionS exp;
struct cfi_insn_data *i;
offsetT augmentation_size;
int enc;
enum dwarf2_format fmt = DWARF2_FORMAT (now_seg);
cie->start_address = symbol_temp_new_now ();
after_size_address = symbol_temp_make ();
end_address = symbol_temp_make ();
exp.X_op = O_subtract;
exp.X_add_symbol = end_address;
exp.X_op_symbol = after_size_address;
exp.X_add_number = 0;
if (eh_frame || fmt == dwarf2_format_32bit)
emit_expr (&exp, 4); /* Length. */
else
{
if (fmt == dwarf2_format_64bit)
out_four (-1);
emit_expr (&exp, 8); /* Length. */
}
symbol_set_value_now (after_size_address);
if (eh_frame)
out_four (0); /* CIE id. */
else
{
out_four (-1); /* CIE id. */
if (fmt != dwarf2_format_32bit)
out_four (-1);
}
out_one (flag_dwarf_cie_version); /* Version. */
if (eh_frame)
{
out_one ('z'); /* Augmentation. */
if (cie->per_encoding != DW_EH_PE_omit)
out_one ('P');
if (cie->lsda_encoding != DW_EH_PE_omit)
out_one ('L');
out_one ('R');
#ifdef tc_output_cie_extra
tc_output_cie_extra (cie);
#endif
}
if (cie->signal_frame)
out_one ('S');
out_one (0);
if (flag_dwarf_cie_version >= 4)
{
/* For now we are assuming a flat address space with 4 or 8 byte
addresses. */
int address_size = dwarf2_format_32bit ? 4 : 8;
out_one (address_size); /* Address size. */
out_one (0); /* Segment size. */
}
out_uleb128 (DWARF2_LINE_MIN_INSN_LENGTH); /* Code alignment. */
out_sleb128 (DWARF2_CIE_DATA_ALIGNMENT); /* Data alignment. */
if (flag_dwarf_cie_version == 1) /* Return column. */
{
if ((cie->return_column & 0xff) != cie->return_column)
as_bad (_("return column number %d overflows in CIE version 1"),
cie->return_column);
out_one (cie->return_column);
}
else
out_uleb128 (cie->return_column);
if (eh_frame)
{
augmentation_size = 1 + (cie->lsda_encoding != DW_EH_PE_omit);
if (cie->per_encoding != DW_EH_PE_omit)
augmentation_size += 1 + encoding_size (cie->per_encoding);
out_uleb128 (augmentation_size); /* Augmentation size. */
emit_expr_encoded (&cie->personality, cie->per_encoding, true);
if (cie->lsda_encoding != DW_EH_PE_omit)
out_one (cie->lsda_encoding);
}
switch (DWARF2_FDE_RELOC_SIZE)
{
case 2:
enc = DW_EH_PE_sdata2;
break;
case 4:
enc = DW_EH_PE_sdata4;
break;
case 8:
enc = DW_EH_PE_sdata8;
break;
default:
abort ();
}
#if CFI_DIFF_EXPR_OK || defined tc_cfi_emit_pcrel_expr
enc |= DW_EH_PE_pcrel;
#endif
#ifdef DWARF2_FDE_RELOC_ENCODING
/* Allow target to override encoding. */
enc = DWARF2_FDE_RELOC_ENCODING (enc);
#endif
cie->fde_encoding = enc;
if (eh_frame)
out_one (enc);
if (cie->first)
{
for (i = cie->first; i != cie->last; i = i->next)
{
if (CUR_SEG (i) != CUR_SEG (cie))
continue;
output_cfi_insn (i);
}
}
frag_align (align, DW_CFA_nop, 0);
symbol_set_value_now (end_address);
}
static void
output_fde (struct fde_entry *fde, struct cie_entry *cie,
bool eh_frame, struct cfi_insn_data *first,
int align)
{
symbolS *after_size_address, *end_address;
expressionS exp;
offsetT augmentation_size;
enum dwarf2_format fmt = DWARF2_FORMAT (now_seg);
unsigned int offset_size;
unsigned int addr_size;
after_size_address = symbol_temp_make ();
end_address = symbol_temp_make ();
exp.X_op = O_subtract;
exp.X_add_symbol = end_address;
exp.X_op_symbol = after_size_address;
exp.X_add_number = 0;
if (eh_frame || fmt == dwarf2_format_32bit)
offset_size = 4;
else
{
if (fmt == dwarf2_format_64bit)
out_four (-1);
offset_size = 8;
}
emit_expr (&exp, offset_size); /* Length. */
symbol_set_value_now (after_size_address);
if (eh_frame)
{
exp.X_op = O_subtract;
exp.X_add_symbol = after_size_address;
exp.X_op_symbol = cie->start_address;
exp.X_add_number = 0;
emit_expr (&exp, offset_size); /* CIE offset. */
}
else
{
TC_DWARF2_EMIT_OFFSET (cie->start_address, offset_size);
}
exp.X_op = O_symbol;
if (eh_frame)
{
bfd_reloc_code_real_type code
= tc_cfi_reloc_for_encoding (cie->fde_encoding);
addr_size = DWARF2_FDE_RELOC_SIZE;
if (code != BFD_RELOC_NONE)
{
reloc_howto_type *howto = bfd_reloc_type_lookup (stdoutput, code);
char *p = frag_more (addr_size);
gas_assert (addr_size == (unsigned) howto->bitsize / 8);
md_number_to_chars (p, 0, addr_size);
fix_new (frag_now, p - frag_now->fr_literal, addr_size,
fde->start_address, 0, howto->pc_relative, code);
}
else
{
exp.X_op = O_subtract;
exp.X_add_number = 0;
#if CFI_DIFF_EXPR_OK
exp.X_add_symbol = fde->start_address;
exp.X_op_symbol = symbol_temp_new_now ();
emit_expr (&exp, addr_size); /* Code offset. */
#else
exp.X_op = O_symbol;
exp.X_add_symbol = fde->start_address;
#if defined(tc_cfi_emit_pcrel_expr)
tc_cfi_emit_pcrel_expr (&exp, addr_size); /* Code offset. */
#else
emit_expr (&exp, addr_size); /* Code offset. */
#endif
#endif
}
}
else
{
exp.X_add_number = 0;
exp.X_add_symbol = fde->start_address;
addr_size = DWARF2_ADDR_SIZE (stdoutput);
emit_expr (&exp, addr_size);
}
exp.X_op = O_subtract;
exp.X_add_symbol = fde->end_address;
exp.X_op_symbol = fde->start_address; /* Code length. */
exp.X_add_number = 0;
emit_expr (&exp, addr_size);
augmentation_size = encoding_size (fde->lsda_encoding);
if (eh_frame)
out_uleb128 (augmentation_size); /* Augmentation size. */
emit_expr_encoded (&fde->lsda, cie->lsda_encoding, false);
for (; first; first = first->next)
if (CUR_SEG (first) == CUR_SEG (fde))
output_cfi_insn (first);
frag_align (align, DW_CFA_nop, 0);
symbol_set_value_now (end_address);
}
/* Allow these insns to be put in the initial sequence of a CIE.
If J is non-NULL, then compare I and J insns for a match. */
static inline bool
initial_cie_insn (const struct cfi_insn_data *i, const struct cfi_insn_data *j)
{
if (j && i->insn != j->insn)
return false;
switch (i->insn)
{
case DW_CFA_offset:
case DW_CFA_def_cfa:
case DW_CFA_val_offset:
if (j)
{
if (i->u.ri.reg != j->u.ri.reg)
return false;
if (i->u.ri.offset != j->u.ri.offset)
return false;
}
break;
case DW_CFA_register:
if (j)
{
if (i->u.rr.reg1 != j->u.rr.reg1)
return false;
if (i->u.rr.reg2 != j->u.rr.reg2)
return false;
}
break;
case DW_CFA_def_cfa_register:
case DW_CFA_restore:
case DW_CFA_undefined:
case DW_CFA_same_value:
if (j)
{
if (i->u.r != j->u.r)
return false;
}
break;
case DW_CFA_def_cfa_offset:
if (j)
{
if (i->u.i != j->u.i)
return false;
}
break;
default:
return false;
}
return true;
}
static struct cie_entry *
select_cie_for_fde (struct fde_entry *fde, bool eh_frame,
struct cfi_insn_data **pfirst, int align)
{
struct cfi_insn_data *i, *j;
struct cie_entry *cie;
for (cie = cie_root; cie; cie = cie->next)
{
if (CUR_SEG (cie) != CUR_SEG (fde))
continue;
#ifdef tc_cie_fde_equivalent_extra
if (!tc_cie_fde_equivalent_extra (cie, fde))
continue;
#endif
if (cie->return_column != fde->return_column
|| cie->signal_frame != fde->signal_frame
|| cie->per_encoding != fde->per_encoding
|| cie->lsda_encoding != fde->lsda_encoding)
continue;
if (cie->per_encoding != DW_EH_PE_omit)
{
if (cie->personality.X_op != fde->personality.X_op
|| (cie->personality.X_add_number
!= fde->personality.X_add_number))
continue;
switch (cie->personality.X_op)
{
case O_constant:
if (cie->personality.X_unsigned != fde->personality.X_unsigned)
continue;
break;
case O_symbol:
if (cie->personality.X_add_symbol
!= fde->personality.X_add_symbol)
continue;
break;
default:
abort ();
}
}
for (i = cie->first, j = fde->data;
i != cie->last && j != NULL;
i = i->next, j = j->next)
{
if (!initial_cie_insn (i, j))
break;
}
if (i == cie->last)
{
*pfirst = j;
return cie;
}
}
cie = XNEW (struct cie_entry);
cie->next = cie_root;
cie_root = cie;
SET_CUR_SEG (cie, CUR_SEG (fde));
cie->return_column = fde->return_column;
cie->signal_frame = fde->signal_frame;
cie->per_encoding = fde->per_encoding;
cie->lsda_encoding = fde->lsda_encoding;
cie->personality = fde->personality;
cie->first = fde->data;
#ifdef tc_cie_entry_init_extra
tc_cie_entry_init_extra (cie, fde)
#endif
for (i = cie->first; i ; i = i->next)
if (!initial_cie_insn (i, NULL))
break;
cie->last = i;
*pfirst = i;
output_cie (cie, eh_frame, align);
return cie;
}
#ifdef md_reg_eh_frame_to_debug_frame
static void
cfi_change_reg_numbers (struct cfi_insn_data *insn, segT ccseg)
{
for (; insn; insn = insn->next)
{
if (CUR_SEG (insn) != ccseg)
continue;
switch (insn->insn)
{
case DW_CFA_advance_loc:
case DW_CFA_def_cfa_offset:
case DW_CFA_remember_state:
case DW_CFA_restore_state:
case DW_CFA_GNU_window_save:
case CFI_escape:
case CFI_label:
break;
case DW_CFA_def_cfa:
case DW_CFA_offset:
insn->u.ri.reg = md_reg_eh_frame_to_debug_frame (insn->u.ri.reg);
break;
case DW_CFA_def_cfa_register:
case DW_CFA_undefined:
case DW_CFA_same_value:
case DW_CFA_restore:
insn->u.r = md_reg_eh_frame_to_debug_frame (insn->u.r);
break;
case DW_CFA_register:
insn->u.rr.reg1 = md_reg_eh_frame_to_debug_frame (insn->u.rr.reg1);
insn->u.rr.reg2 = md_reg_eh_frame_to_debug_frame (insn->u.rr.reg2);
break;
case CFI_val_encoded_addr:
insn->u.ea.reg = md_reg_eh_frame_to_debug_frame (insn->u.ea.reg);
break;
default:
abort ();
}
}
}
#else
#define cfi_change_reg_numbers(insn, cseg) do { } while (0)
#endif
#if SUPPORT_COMPACT_EH
static void
cfi_emit_eh_header (symbolS *sym, bfd_vma addend)
{
expressionS exp;
exp.X_add_number = addend;
exp.X_add_symbol = sym;
emit_expr_encoded (&exp, DW_EH_PE_sdata4 | DW_EH_PE_pcrel, false);
}
static void
output_eh_header (struct fde_entry *fde)
{
char *p;
bfd_vma addend;
if (fde->eh_header_type == EH_COMPACT_INLINE)
addend = 0;
else
addend = 1;
cfi_emit_eh_header (fde->start_address, addend);
if (fde->eh_header_type == EH_COMPACT_INLINE)
{
p = frag_more (4);
/* Inline entries always use PR1. */
*(p++) = 1;
memcpy(p, fde->eh_data, 3);
}
else
{
if (fde->eh_header_type == EH_COMPACT_LEGACY)
addend = 1;
else if (fde->eh_header_type == EH_COMPACT_OUTLINE
|| fde->eh_header_type == EH_COMPACT_OUTLINE_DONE)
addend = 0;
else
abort ();
cfi_emit_eh_header (fde->eh_loc, addend);
}
}
#endif
void
cfi_finish (void)
{
struct cie_entry *cie, *cie_next;
segT cfi_seg, ccseg;
struct fde_entry *fde;
struct cfi_insn_data *first;
int save_flag_traditional_format, seek_next_seg;
if (all_fde_data == 0)
return;
cfi_sections_set = true;
if ((all_cfi_sections & CFI_EMIT_eh_frame) != 0
|| (all_cfi_sections & CFI_EMIT_eh_frame_compact) != 0)
{
/* Make sure check_eh_frame doesn't do anything with our output. */
save_flag_traditional_format = flag_traditional_format;
flag_traditional_format = 1;
if (!EH_FRAME_LINKONCE)
{
/* Open .eh_frame section. */
cfi_seg = get_cfi_seg (NULL, ".eh_frame",
(SEC_ALLOC | SEC_LOAD | SEC_DATA
| DWARF2_EH_FRAME_READ_ONLY),
EH_FRAME_ALIGNMENT);
#ifdef md_fix_up_eh_frame
md_fix_up_eh_frame (cfi_seg);
#else
(void) cfi_seg;
#endif
}
do
{
ccseg = NULL;
seek_next_seg = 0;
for (cie = cie_root; cie; cie = cie_next)
{
cie_next = cie->next;
free ((void *) cie);
}
cie_root = NULL;
for (fde = all_fde_data; fde ; fde = fde->next)
{
if ((fde->sections & CFI_EMIT_eh_frame) == 0
&& (fde->sections & CFI_EMIT_eh_frame_compact) == 0)
continue;
#if SUPPORT_COMPACT_EH
/* Emit a LEGACY format header if we have processed all
of the .cfi directives without encountering either inline or
out-of-line compact unwinding opcodes. */
if (fde->eh_header_type == EH_COMPACT_HAS_LSDA
|| fde->eh_header_type == EH_COMPACT_UNKNOWN)
fde->eh_header_type = EH_COMPACT_LEGACY;
if (fde->eh_header_type != EH_COMPACT_LEGACY)
continue;
#endif
if (EH_FRAME_LINKONCE)
{
if (HANDLED (fde))
continue;
if (seek_next_seg && CUR_SEG (fde) != ccseg)
{
seek_next_seg = 2;
continue;
}
if (!seek_next_seg)
{
ccseg = CUR_SEG (fde);
/* Open .eh_frame section. */
cfi_seg = get_cfi_seg (ccseg, ".eh_frame",
(SEC_ALLOC | SEC_LOAD | SEC_DATA
| DWARF2_EH_FRAME_READ_ONLY),
EH_FRAME_ALIGNMENT);
#ifdef md_fix_up_eh_frame
md_fix_up_eh_frame (cfi_seg);
#else
(void) cfi_seg;
#endif
seek_next_seg = 1;
}
SET_HANDLED (fde, 1);
}
if (fde->end_address == NULL)
{
as_bad (_("open CFI at the end of file; "
"missing .cfi_endproc directive"));
fde->end_address = fde->start_address;
}
cie = select_cie_for_fde (fde, true, &first, 2);
fde->eh_loc = symbol_temp_new_now ();
output_fde (fde, cie, true, first,
fde->next == NULL ? EH_FRAME_ALIGNMENT : 2);
}
}
while (EH_FRAME_LINKONCE && seek_next_seg == 2);
if (EH_FRAME_LINKONCE)
for (fde = all_fde_data; fde ; fde = fde->next)
SET_HANDLED (fde, 0);
#if SUPPORT_COMPACT_EH
if (compact_eh)
{
/* Create remaining out of line table entries. */
do
{
ccseg = NULL;
seek_next_seg = 0;
for (fde = all_fde_data; fde ; fde = fde->next)
{
if ((fde->sections & CFI_EMIT_eh_frame) == 0
&& (fde->sections & CFI_EMIT_eh_frame_compact) == 0)
continue;
if (fde->eh_header_type != EH_COMPACT_OUTLINE)
continue;
if (HANDLED (fde))
continue;
if (seek_next_seg && CUR_SEG (fde) != ccseg)
{
seek_next_seg = 2;
continue;
}
if (!seek_next_seg)
{
ccseg = CUR_SEG (fde);
/* Open .gnu_extab section. */
get_cfi_seg (ccseg, ".gnu_extab",
(SEC_ALLOC | SEC_LOAD | SEC_DATA
| DWARF2_EH_FRAME_READ_ONLY),
1);
seek_next_seg = 1;
}
SET_HANDLED (fde, 1);
frag_align (1, 0, 0);
record_alignment (now_seg, 1);
output_compact_unwind_data (fde, 1);
}
}
while (EH_FRAME_LINKONCE && seek_next_seg == 2);
for (fde = all_fde_data; fde ; fde = fde->next)
SET_HANDLED (fde, 0);
/* Create index table fragments. */
do
{
ccseg = NULL;
seek_next_seg = 0;
for (fde = all_fde_data; fde ; fde = fde->next)
{
if ((fde->sections & CFI_EMIT_eh_frame) == 0
&& (fde->sections & CFI_EMIT_eh_frame_compact) == 0)
continue;
if (HANDLED (fde))
continue;
if (seek_next_seg && CUR_SEG (fde) != ccseg)
{
seek_next_seg = 2;
continue;
}
if (!seek_next_seg)
{
ccseg = CUR_SEG (fde);
/* Open .eh_frame_entry section. */
cfi_seg = get_cfi_seg (ccseg, ".eh_frame_entry",
(SEC_ALLOC | SEC_LOAD | SEC_DATA
| DWARF2_EH_FRAME_READ_ONLY),
2);
seek_next_seg = 1;
}
SET_HANDLED (fde, 1);
output_eh_header (fde);
}
}
while (seek_next_seg == 2);
for (fde = all_fde_data; fde ; fde = fde->next)
SET_HANDLED (fde, 0);
}
#endif /* SUPPORT_COMPACT_EH */
flag_traditional_format = save_flag_traditional_format;
}
cfi_sections_set = true;
if ((all_cfi_sections & CFI_EMIT_debug_frame) != 0)
{
int alignment = ffs (DWARF2_ADDR_SIZE (stdoutput)) - 1;
if (!SUPPORT_FRAME_LINKONCE)
get_cfi_seg (NULL, ".debug_frame",
SEC_READONLY | SEC_DEBUGGING,
alignment);
do
{
ccseg = NULL;
seek_next_seg = 0;
for (cie = cie_root; cie; cie = cie_next)
{
cie_next = cie->next;
free ((void *) cie);
}
cie_root = NULL;
for (fde = all_fde_data; fde ; fde = fde->next)
{
if ((fde->sections & CFI_EMIT_debug_frame) == 0)
continue;
if (SUPPORT_FRAME_LINKONCE)
{
if (HANDLED (fde))
continue;
if (seek_next_seg && CUR_SEG (fde) != ccseg)
{
seek_next_seg = 2;
continue;
}
if (!seek_next_seg)
{
ccseg = CUR_SEG (fde);
/* Open .debug_frame section. */
get_cfi_seg (ccseg, ".debug_frame",
SEC_READONLY | SEC_DEBUGGING,
alignment);
seek_next_seg = 1;
}
SET_HANDLED (fde, 1);
}
if (fde->end_address == NULL)
{
as_bad (_("open CFI at the end of file; "
"missing .cfi_endproc directive"));
fde->end_address = fde->start_address;
}
fde->per_encoding = DW_EH_PE_omit;
fde->lsda_encoding = DW_EH_PE_omit;
cfi_change_reg_numbers (fde->data, ccseg);
cie = select_cie_for_fde (fde, false, &first, alignment);
output_fde (fde, cie, false, first, alignment);
}
}
while (SUPPORT_FRAME_LINKONCE && seek_next_seg == 2);
if (SUPPORT_FRAME_LINKONCE)
for (fde = all_fde_data; fde ; fde = fde->next)
SET_HANDLED (fde, 0);
}
}
#else /* TARGET_USE_CFIPOP */
/* Emit an intelligible error message for missing support. */
static void
dot_cfi_dummy (int ignored ATTRIBUTE_UNUSED)
{
as_bad (_("CFI is not supported for this target"));
ignore_rest_of_line ();
}
const pseudo_typeS cfi_pseudo_table[] =
{
{ "cfi_sections", dot_cfi_dummy, 0 },
{ "cfi_startproc", dot_cfi_dummy, 0 },
{ "cfi_endproc", dot_cfi_dummy, 0 },
{ "cfi_fde_data", dot_cfi_dummy, 0 },
{ "cfi_def_cfa", dot_cfi_dummy, 0 },
{ "cfi_def_cfa_register", dot_cfi_dummy, 0 },
{ "cfi_def_cfa_offset", dot_cfi_dummy, 0 },
{ "cfi_adjust_cfa_offset", dot_cfi_dummy, 0 },
{ "cfi_offset", dot_cfi_dummy, 0 },
{ "cfi_rel_offset", dot_cfi_dummy, 0 },
{ "cfi_register", dot_cfi_dummy, 0 },
{ "cfi_return_column", dot_cfi_dummy, 0 },
{ "cfi_restore", dot_cfi_dummy, 0 },
{ "cfi_undefined", dot_cfi_dummy, 0 },
{ "cfi_same_value", dot_cfi_dummy, 0 },
{ "cfi_remember_state", dot_cfi_dummy, 0 },
{ "cfi_restore_state", dot_cfi_dummy, 0 },
{ "cfi_window_save", dot_cfi_dummy, 0 },
{ "cfi_escape", dot_cfi_dummy, 0 },
{ "cfi_signal_frame", dot_cfi_dummy, 0 },
{ "cfi_personality", dot_cfi_dummy, 0 },
{ "cfi_personality_id", dot_cfi_dummy, 0 },
{ "cfi_lsda", dot_cfi_dummy, 0 },
{ "cfi_val_encoded_addr", dot_cfi_dummy, 0 },
{ "cfi_label", dot_cfi_dummy, 0 },
{ "cfi_inline_lsda", dot_cfi_dummy, 0 },
{ "cfi_val_offset", dot_cfi_dummy, 0 },
{ NULL, NULL, 0 }
};
void
cfi_finish (void)
{
}
#endif /* TARGET_USE_CFIPOP */