/* .eh_frame section optimization.
- Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007
- Free Software Foundation, Inc.
+ Copyright (C) 2001-2020 Free Software Foundation, Inc.
Written by Jakub Jelinek <jakub@redhat.com>.
This file is part of BFD, the Binary File Descriptor library.
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 2 of the License, or
+ 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,
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
+ Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+ MA 02110-1301, USA. */
#include "sysdep.h"
#include "bfd.h"
#include "libbfd.h"
#include "elf-bfd.h"
-#include "elf/dwarf2.h"
+#include "dwarf2.h"
#define EH_FRAME_HDR_SIZE 8
unsigned int length;
unsigned int hash;
unsigned char version;
+ unsigned char local_personality;
char augmentation[20];
bfd_vma code_align;
bfd_signed_vma data_align;
bfd_vma ra_column;
bfd_vma augmentation_size;
- struct elf_link_hash_entry *personality;
- asection *output_sec;
+ union {
+ struct elf_link_hash_entry *h;
+ struct {
+ unsigned int bfd_id;
+ unsigned int index;
+ } sym;
+ unsigned int reloc_index;
+ } personality;
struct eh_cie_fde *cie_inf;
unsigned char per_encoding;
unsigned char lsda_encoding;
unsigned char fde_encoding;
unsigned char initial_insn_length;
- unsigned char make_relative;
- unsigned char make_lsda_relative;
+ unsigned char can_make_lsda_relative;
unsigned char initial_instructions[50];
};
static int
cie_eq (const void *e1, const void *e2)
{
- const struct cie *c1 = e1;
- const struct cie *c2 = e2;
+ const struct cie *c1 = (const struct cie *) e1;
+ const struct cie *c2 = (const struct cie *) e2;
if (c1->hash == c2->hash
&& c1->length == c2->length
&& c1->version == c2->version
+ && c1->local_personality == c2->local_personality
&& strcmp (c1->augmentation, c2->augmentation) == 0
&& strcmp (c1->augmentation, "eh") != 0
&& c1->code_align == c2->code_align
&& c1->data_align == c2->data_align
&& c1->ra_column == c2->ra_column
&& c1->augmentation_size == c2->augmentation_size
- && c1->personality == c2->personality
- && c1->output_sec == c2->output_sec
+ && memcmp (&c1->personality, &c2->personality,
+ sizeof (c1->personality)) == 0
+ && (c1->cie_inf->u.cie.u.sec->output_section
+ == c2->cie_inf->u.cie.u.sec->output_section)
&& c1->per_encoding == c2->per_encoding
&& c1->lsda_encoding == c2->lsda_encoding
&& c1->fde_encoding == c2->fde_encoding
&& c1->initial_insn_length == c2->initial_insn_length
+ && c1->initial_insn_length <= sizeof (c1->initial_instructions)
&& memcmp (c1->initial_instructions,
c2->initial_instructions,
c1->initial_insn_length) == 0)
static hashval_t
cie_hash (const void *e)
{
- const struct cie *c = e;
+ const struct cie *c = (const struct cie *) e;
return c->hash;
}
cie_compute_hash (struct cie *c)
{
hashval_t h = 0;
+ size_t len;
h = iterative_hash_object (c->length, h);
h = iterative_hash_object (c->version, h);
h = iterative_hash (c->augmentation, strlen (c->augmentation) + 1, h);
h = iterative_hash_object (c->ra_column, h);
h = iterative_hash_object (c->augmentation_size, h);
h = iterative_hash_object (c->personality, h);
- h = iterative_hash_object (c->output_sec, h);
+ h = iterative_hash_object (c->cie_inf->u.cie.u.sec->output_section, h);
h = iterative_hash_object (c->per_encoding, h);
h = iterative_hash_object (c->lsda_encoding, h);
h = iterative_hash_object (c->fde_encoding, h);
h = iterative_hash_object (c->initial_insn_length, h);
- h = iterative_hash (c->initial_instructions, c->initial_insn_length, h);
+ len = c->initial_insn_length;
+ if (len > sizeof (c->initial_instructions))
+ len = sizeof (c->initial_instructions);
+ h = iterative_hash (c->initial_instructions, len, h);
c->hash = h;
return h;
}
{
if (entry->add_augmentation_size)
size++;
- if (entry->add_fde_encoding)
+ if (entry->u.cie.add_fde_encoding)
size++;
}
return size;
extra_augmentation_data_bytes (struct eh_cie_fde *entry)
{
unsigned int size = 0;
- if (entry->cie)
- {
- if (entry->add_augmentation_size)
- size++;
- if (entry->add_fde_encoding)
- size++;
- }
- else
- {
- if (entry->cie_inf->add_augmentation_size)
- size++;
- }
+ if (entry->add_augmentation_size)
+ size++;
+ if (entry->cie && entry->u.cie.add_fde_encoding)
+ size++;
return size;
}
-/* Return the size that ENTRY will have in the output. ALIGNMENT is the
- required alignment of ENTRY in bytes. */
+/* Return the size that ENTRY will have in the output. */
static unsigned int
-size_of_output_cie_fde (struct eh_cie_fde *entry, unsigned int alignment)
+size_of_output_cie_fde (struct eh_cie_fde *entry)
{
if (entry->removed)
return 0;
return 4;
return (entry->size
+ extra_augmentation_string_bytes (entry)
- + extra_augmentation_data_bytes (entry)
- + alignment - 1) & -alignment;
+ + extra_augmentation_data_bytes (entry));
+}
+
+/* Return the offset of the FDE or CIE after ENT. */
+
+static unsigned int
+next_cie_fde_offset (const struct eh_cie_fde *ent,
+ const struct eh_cie_fde *last,
+ const asection *sec)
+{
+ while (++ent < last)
+ {
+ if (!ent->removed)
+ return ent->new_offset;
+ }
+ return sec->size;
}
/* Assume that the bytes between *ITER and END are CFA instructions.
return last;
}
-/* This function is called for each input file before the .eh_frame
- section is relocated. It discards duplicate CIEs and FDEs for discarded
- functions. The function returns TRUE iff any entries have been
- deleted. */
+/* Convert absolute encoding ENCODING into PC-relative form.
+ SIZE is the size of a pointer. */
+
+static unsigned char
+make_pc_relative (unsigned char encoding, unsigned int ptr_size)
+{
+ if ((encoding & 0x7f) == DW_EH_PE_absptr)
+ switch (ptr_size)
+ {
+ case 2:
+ encoding |= DW_EH_PE_sdata2;
+ break;
+ case 4:
+ encoding |= DW_EH_PE_sdata4;
+ break;
+ case 8:
+ encoding |= DW_EH_PE_sdata8;
+ break;
+ }
+ return encoding | DW_EH_PE_pcrel;
+}
+
+/* Examine each .eh_frame_entry section and discard those
+ those that are marked SEC_EXCLUDE. */
+
+static void
+bfd_elf_discard_eh_frame_entry (struct eh_frame_hdr_info *hdr_info)
+{
+ unsigned int i;
+ for (i = 0; i < hdr_info->array_count; i++)
+ {
+ if (hdr_info->u.compact.entries[i]->flags & SEC_EXCLUDE)
+ {
+ unsigned int j;
+ for (j = i + 1; j < hdr_info->array_count; j++)
+ hdr_info->u.compact.entries[j-1] = hdr_info->u.compact.entries[j];
+
+ hdr_info->array_count--;
+ hdr_info->u.compact.entries[hdr_info->array_count] = NULL;
+ i--;
+ }
+ }
+}
+
+/* Add a .eh_frame_entry section. */
+
+static void
+bfd_elf_record_eh_frame_entry (struct eh_frame_hdr_info *hdr_info,
+ asection *sec)
+{
+ if (hdr_info->array_count == hdr_info->u.compact.allocated_entries)
+ {
+ if (hdr_info->u.compact.allocated_entries == 0)
+ {
+ hdr_info->frame_hdr_is_compact = TRUE;
+ hdr_info->u.compact.allocated_entries = 2;
+ hdr_info->u.compact.entries =
+ bfd_malloc (hdr_info->u.compact.allocated_entries
+ * sizeof (hdr_info->u.compact.entries[0]));
+ }
+ else
+ {
+ hdr_info->u.compact.allocated_entries *= 2;
+ hdr_info->u.compact.entries =
+ bfd_realloc (hdr_info->u.compact.entries,
+ hdr_info->u.compact.allocated_entries
+ * sizeof (hdr_info->u.compact.entries[0]));
+ }
+
+ BFD_ASSERT (hdr_info->u.compact.entries);
+ }
+
+ hdr_info->u.compact.entries[hdr_info->array_count++] = sec;
+}
+
+/* Parse a .eh_frame_entry section. Figure out which text section it
+ references. */
bfd_boolean
-_bfd_elf_discard_section_eh_frame
- (bfd *abfd, struct bfd_link_info *info, asection *sec,
- bfd_boolean (*reloc_symbol_deleted_p) (bfd_vma, void *),
- struct elf_reloc_cookie *cookie)
+_bfd_elf_parse_eh_frame_entry (struct bfd_link_info *info,
+ asection *sec, struct elf_reloc_cookie *cookie)
+{
+ struct elf_link_hash_table *htab;
+ struct eh_frame_hdr_info *hdr_info;
+ unsigned long r_symndx;
+ asection *text_sec;
+
+ htab = elf_hash_table (info);
+ hdr_info = &htab->eh_info;
+
+ if (sec->size == 0
+ || sec->sec_info_type != SEC_INFO_TYPE_NONE)
+ {
+ return TRUE;
+ }
+
+ if (sec->output_section && bfd_is_abs_section (sec->output_section))
+ {
+ /* At least one of the sections is being discarded from the
+ link, so we should just ignore them. */
+ return TRUE;
+ }
+
+ if (cookie->rel == cookie->relend)
+ return FALSE;
+
+ /* The first relocation is the function start. */
+ r_symndx = cookie->rel->r_info >> cookie->r_sym_shift;
+ if (r_symndx == STN_UNDEF)
+ return FALSE;
+
+ text_sec = _bfd_elf_section_for_symbol (cookie, r_symndx, FALSE);
+
+ if (text_sec == NULL)
+ return FALSE;
+
+ elf_section_eh_frame_entry (text_sec) = sec;
+ if (text_sec->output_section
+ && bfd_is_abs_section (text_sec->output_section))
+ sec->flags |= SEC_EXCLUDE;
+
+ sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME_ENTRY;
+ elf_section_data (sec)->sec_info = text_sec;
+ bfd_elf_record_eh_frame_entry (hdr_info, sec);
+ return TRUE;
+}
+
+/* Try to parse .eh_frame section SEC, which belongs to ABFD. Store the
+ information in the section's sec_info field on success. COOKIE
+ describes the relocations in SEC. */
+
+void
+_bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
+ asection *sec, struct elf_reloc_cookie *cookie)
{
#define REQUIRE(COND) \
do \
goto free_no_table; \
while (0)
- bfd_byte *ehbuf = NULL, *buf;
+ bfd_byte *ehbuf = NULL, *buf, *end;
bfd_byte *last_fde;
- struct eh_cie_fde *ent, *this_inf;
+ struct eh_cie_fde *this_inf;
unsigned int hdr_length, hdr_id;
- struct extended_cie
- {
- struct cie cie;
- unsigned int offset;
- unsigned int usage_count;
- unsigned int entry;
- } *ecies = NULL, *ecie;
- unsigned int ecie_count = 0, ecie_alloced = 0;
- struct cie *cie;
+ unsigned int cie_count;
+ struct cie *cie, *local_cies = NULL;
struct elf_link_hash_table *htab;
struct eh_frame_hdr_info *hdr_info;
struct eh_frame_sec_info *sec_info = NULL;
- unsigned int offset;
unsigned int ptr_size;
- unsigned int entry_alloced;
+ unsigned int num_cies;
+ unsigned int num_entries;
+ elf_gc_mark_hook_fn gc_mark_hook;
- if (sec->size == 0)
+ htab = elf_hash_table (info);
+ hdr_info = &htab->eh_info;
+
+ if (sec->size == 0
+ || sec->sec_info_type != SEC_INFO_TYPE_NONE)
{
/* This file does not contain .eh_frame information. */
- return FALSE;
+ return;
}
if (bfd_is_abs_section (sec->output_section))
{
/* At least one of the sections is being discarded from the
link, so we should just ignore them. */
- return FALSE;
+ return;
}
- htab = elf_hash_table (info);
- hdr_info = &htab->eh_info;
-
- if (hdr_info->cies == NULL && !info->relocatable)
- hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free);
-
/* Read the frame unwind information from abfd. */
REQUIRE (bfd_malloc_and_get_section (abfd, sec, &ehbuf));
- if (sec->size >= 4
- && bfd_get_32 (abfd, ehbuf) == 0
- && cookie->rel == cookie->relend)
- {
- /* Empty .eh_frame section. */
- free (ehbuf);
- return FALSE;
- }
-
/* If .eh_frame section size doesn't fit into int, we cannot handle
it (it would need to use 64-bit .eh_frame format anyway). */
REQUIRE (sec->size == (unsigned int) sec->size);
->elf_backend_eh_frame_address_size (abfd, sec));
REQUIRE (ptr_size != 0);
+ /* Go through the section contents and work out how many FDEs and
+ CIEs there are. */
buf = ehbuf;
- sec_info = bfd_zmalloc (sizeof (struct eh_frame_sec_info)
- + 99 * sizeof (struct eh_cie_fde));
+ end = ehbuf + sec->size;
+ num_cies = 0;
+ num_entries = 0;
+ while (buf != end)
+ {
+ num_entries++;
+
+ /* Read the length of the entry. */
+ REQUIRE (skip_bytes (&buf, end, 4));
+ hdr_length = bfd_get_32 (abfd, buf - 4);
+
+ /* 64-bit .eh_frame is not supported. */
+ REQUIRE (hdr_length != 0xffffffff);
+ if (hdr_length == 0)
+ break;
+
+ REQUIRE (skip_bytes (&buf, end, 4));
+ hdr_id = bfd_get_32 (abfd, buf - 4);
+ if (hdr_id == 0)
+ num_cies++;
+
+ REQUIRE (skip_bytes (&buf, end, hdr_length - 4));
+ }
+
+ sec_info = (struct eh_frame_sec_info *)
+ bfd_zmalloc (sizeof (struct eh_frame_sec_info)
+ + (num_entries - 1) * sizeof (struct eh_cie_fde));
REQUIRE (sec_info);
- entry_alloced = 100;
+ /* We need to have a "struct cie" for each CIE in this section. */
+ if (num_cies)
+ {
+ local_cies = (struct cie *) bfd_zmalloc (num_cies * sizeof (*local_cies));
+ REQUIRE (local_cies);
+ }
+ /* FIXME: octets_per_byte. */
#define ENSURE_NO_RELOCS(buf) \
- REQUIRE (!(cookie->rel < cookie->relend \
- && (cookie->rel->r_offset \
- < (bfd_size_type) ((buf) - ehbuf)) \
- && cookie->rel->r_info != 0))
+ while (cookie->rel < cookie->relend \
+ && (cookie->rel->r_offset \
+ < (bfd_size_type) ((buf) - ehbuf))) \
+ { \
+ REQUIRE (cookie->rel->r_info == 0); \
+ cookie->rel++; \
+ }
+ /* FIXME: octets_per_byte. */
#define SKIP_RELOCS(buf) \
while (cookie->rel < cookie->relend \
&& (cookie->rel->r_offset \
< (bfd_size_type) ((buf) - ehbuf))) \
cookie->rel++
+ /* FIXME: octets_per_byte. */
#define GET_RELOC(buf) \
((cookie->rel < cookie->relend \
&& (cookie->rel->r_offset \
== (bfd_size_type) ((buf) - ehbuf))) \
? cookie->rel : NULL)
- for (;;)
+ buf = ehbuf;
+ cie_count = 0;
+ gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
+ while ((bfd_size_type) (buf - ehbuf) != sec->size)
{
char *aug;
- bfd_byte *start, *end, *insns, *insns_end;
+ bfd_byte *start, *insns, *insns_end;
bfd_size_type length;
unsigned int set_loc_count;
- if (sec_info->count == entry_alloced)
- {
- sec_info = bfd_realloc (sec_info,
- sizeof (struct eh_frame_sec_info)
- + ((entry_alloced + 99)
- * sizeof (struct eh_cie_fde)));
- REQUIRE (sec_info);
-
- memset (&sec_info->entry[entry_alloced], 0,
- 100 * sizeof (struct eh_cie_fde));
- entry_alloced += 100;
- }
-
this_inf = sec_info->entry + sec_info->count;
last_fde = buf;
- if ((bfd_size_type) (buf - ehbuf) == sec->size)
- break;
-
/* Read the length of the entry. */
REQUIRE (skip_bytes (&buf, ehbuf + sec->size, 4));
hdr_length = bfd_get_32 (abfd, buf - 4);
- /* 64-bit .eh_frame is not supported. */
- REQUIRE (hdr_length != 0xffffffff);
-
/* The CIE/FDE must be fully contained in this input section. */
REQUIRE ((bfd_size_type) (buf - ehbuf) + hdr_length <= sec->size);
end = buf + hdr_length;
this_inf->offset = last_fde - ehbuf;
this_inf->size = 4 + hdr_length;
+ this_inf->reloc_index = cookie->rel - cookie->rels;
if (hdr_length == 0)
{
/* A zero-length CIE should only be found at the end of
- the section. */
+ the section, but allow multiple terminators. */
+ while (skip_bytes (&buf, ehbuf + sec->size, 4))
+ REQUIRE (bfd_get_32 (abfd, buf - 4) == 0);
REQUIRE ((bfd_size_type) (buf - ehbuf) == sec->size);
ENSURE_NO_RELOCS (buf);
sec_info->count++;
/* CIE */
this_inf->cie = 1;
- if (ecie_count == ecie_alloced)
- {
- ecies = bfd_realloc (ecies,
- (ecie_alloced + 20) * sizeof (*ecies));
- REQUIRE (ecies);
- memset (&ecies[ecie_alloced], 0, 20 * sizeof (*ecies));
- ecie_alloced += 20;
- }
+ /* Point CIE to one of the section-local cie structures. */
+ cie = local_cies + cie_count++;
- cie = &ecies[ecie_count].cie;
- ecies[ecie_count].offset = this_inf->offset;
- ecies[ecie_count++].entry = sec_info->count;
+ cie->cie_inf = this_inf;
cie->length = hdr_length;
start = buf;
REQUIRE (read_byte (&buf, end, &cie->version));
/* Cannot handle unknown versions. */
- REQUIRE (cie->version == 1 || cie->version == 3);
+ REQUIRE (cie->version == 1
+ || cie->version == 3
+ || cie->version == 4);
REQUIRE (strlen ((char *) buf) < sizeof (cie->augmentation));
strcpy (cie->augmentation, (char *) buf);
buf = (bfd_byte *) strchr ((char *) buf, '\0') + 1;
+ this_inf->u.cie.aug_str_len = buf - start - 1;
ENSURE_NO_RELOCS (buf);
if (buf[0] == 'e' && buf[1] == 'h')
{
REQUIRE (skip_bytes (&buf, end, ptr_size));
SKIP_RELOCS (buf);
}
+ if (cie->version >= 4)
+ {
+ REQUIRE (buf + 1 < end);
+ REQUIRE (buf[0] == ptr_size);
+ REQUIRE (buf[1] == 0);
+ buf += 2;
+ }
REQUIRE (read_uleb128 (&buf, end, &cie->code_align));
REQUIRE (read_sleb128 (&buf, end, &cie->data_align));
if (cie->version == 1)
{
aug++;
REQUIRE (read_uleb128 (&buf, end, &cie->augmentation_size));
- ENSURE_NO_RELOCS (buf);
+ ENSURE_NO_RELOCS (buf);
}
while (*aug != '\0')
switch (*aug++)
{
+ case 'B':
+ break;
case 'L':
REQUIRE (read_byte (&buf, end, &cie->lsda_encoding));
ENSURE_NO_RELOCS (buf);
per_width = get_DW_EH_PE_width (cie->per_encoding,
ptr_size);
REQUIRE (per_width);
- if ((cie->per_encoding & 0xf0) == DW_EH_PE_aligned)
+ if ((cie->per_encoding & 0x70) == DW_EH_PE_aligned)
{
length = -(buf - ehbuf) & (per_width - 1);
REQUIRE (skip_bytes (&buf, end, length));
+ if (per_width == 8)
+ this_inf->u.cie.per_encoding_aligned8 = 1;
}
+ this_inf->u.cie.personality_offset = buf - start;
ENSURE_NO_RELOCS (buf);
- /* Ensure we have a reloc here, against
- a global symbol. */
- if (GET_RELOC (buf) != NULL)
- {
- unsigned long r_symndx;
-
-#ifdef BFD64
- if (ptr_size == 8)
- r_symndx = ELF64_R_SYM (cookie->rel->r_info);
- else
-#endif
- r_symndx = ELF32_R_SYM (cookie->rel->r_info);
- if (r_symndx >= cookie->locsymcount)
- {
- struct elf_link_hash_entry *h;
-
- r_symndx -= cookie->extsymoff;
- h = cookie->sym_hashes[r_symndx];
-
- while (h->root.type == bfd_link_hash_indirect
- || h->root.type == bfd_link_hash_warning)
- h = (struct elf_link_hash_entry *)
- h->root.u.i.link;
-
- cie->personality = h;
- }
- /* Cope with MIPS-style composite relocations. */
- do
- cookie->rel++;
- while (GET_RELOC (buf) != NULL);
- }
+ /* Ensure we have a reloc here. */
+ REQUIRE (GET_RELOC (buf));
+ cie->personality.reloc_index
+ = cookie->rel - cookie->rels;
+ /* Cope with MIPS-style composite relocations. */
+ do
+ cookie->rel++;
+ while (GET_RELOC (buf) != NULL);
REQUIRE (skip_bytes (&buf, end, per_width));
- REQUIRE (cie->personality);
}
break;
default:
goto free_no_table;
}
}
+ this_inf->u.cie.aug_data_len
+ = buf - start - 1 - this_inf->u.cie.aug_str_len;
/* For shared libraries, try to get rid of as many RELATIVE relocs
as possible. */
- if (info->shared
+ if (bfd_link_pic (info)
&& (get_elf_backend_data (abfd)
->elf_backend_can_make_relative_eh_frame
(abfd, info, sec)))
{
- if ((cie->fde_encoding & 0xf0) == DW_EH_PE_absptr)
- cie->make_relative = 1;
+ if ((cie->fde_encoding & 0x70) == DW_EH_PE_absptr)
+ this_inf->make_relative = 1;
/* If the CIE doesn't already have an 'R' entry, it's fairly
easy to add one, provided that there's no aligned data
after the augmentation string. */
else if (cie->fde_encoding == DW_EH_PE_omit
- && (cie->per_encoding & 0xf0) != DW_EH_PE_aligned)
+ && (cie->per_encoding & 0x70) != DW_EH_PE_aligned)
{
if (*cie->augmentation == 0)
this_inf->add_augmentation_size = 1;
- this_inf->add_fde_encoding = 1;
- cie->make_relative = 1;
+ this_inf->u.cie.add_fde_encoding = 1;
+ this_inf->make_relative = 1;
}
- }
- if (info->shared
- && (get_elf_backend_data (abfd)
- ->elf_backend_can_make_lsda_relative_eh_frame
- (abfd, info, sec))
- && (cie->lsda_encoding & 0xf0) == DW_EH_PE_absptr)
- cie->make_lsda_relative = 1;
+ if ((cie->lsda_encoding & 0x70) == DW_EH_PE_absptr)
+ cie->can_make_lsda_relative = 1;
+ }
/* If FDE encoding was not specified, it defaults to
DW_EH_absptr. */
cie->fde_encoding = DW_EH_PE_absptr;
initial_insn_length = end - buf;
- if (initial_insn_length <= sizeof (cie->initial_instructions))
- {
- cie->initial_insn_length = initial_insn_length;
- memcpy (cie->initial_instructions, buf, initial_insn_length);
- }
+ cie->initial_insn_length = initial_insn_length;
+ memcpy (cie->initial_instructions, buf,
+ initial_insn_length <= sizeof (cie->initial_instructions)
+ ? initial_insn_length : sizeof (cie->initial_instructions));
insns = buf;
buf += initial_insn_length;
ENSURE_NO_RELOCS (buf);
+
+ if (!bfd_link_relocatable (info))
+ {
+ /* Keep info for merging cies. */
+ this_inf->u.cie.u.full_cie = cie;
+ this_inf->u.cie.per_encoding_relative
+ = (cie->per_encoding & 0x70) == DW_EH_PE_pcrel;
+ }
}
else
{
/* Find the corresponding CIE. */
unsigned int cie_offset = this_inf->offset + 4 - hdr_id;
- for (ecie = ecies; ecie < ecies + ecie_count; ++ecie)
- if (cie_offset == ecie->offset)
+ for (cie = local_cies; cie < local_cies + cie_count; cie++)
+ if (cie_offset == cie->cie_inf->offset)
break;
/* Ensure this FDE references one of the CIEs in this input
section. */
- REQUIRE (ecie != ecies + ecie_count);
- cie = &ecie->cie;
+ REQUIRE (cie != local_cies + cie_count);
+ this_inf->u.fde.cie_inf = cie->cie_inf;
+ this_inf->make_relative = cie->cie_inf->make_relative;
+ this_inf->add_augmentation_size
+ = cie->cie_inf->add_augmentation_size;
ENSURE_NO_RELOCS (buf);
- REQUIRE (GET_RELOC (buf));
-
- if ((*reloc_symbol_deleted_p) (buf - ehbuf, cookie))
- /* This is a FDE against a discarded section. It should
- be deleted. */
- this_inf->removed = 1;
- else
+ if ((sec->flags & SEC_LINKER_CREATED) == 0 || cookie->rels != NULL)
{
- if (info->shared
- && (((cie->fde_encoding & 0xf0) == DW_EH_PE_absptr
- && cie->make_relative == 0)
- || (cie->fde_encoding & 0xf0) == DW_EH_PE_aligned))
+ asection *rsec;
+
+ REQUIRE (GET_RELOC (buf));
+
+ /* Chain together the FDEs for each section. */
+ rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook,
+ cookie, NULL);
+ /* RSEC will be NULL if FDE was cleared out as it was belonging to
+ a discarded SHT_GROUP. */
+ if (rsec)
{
- /* If a shared library uses absolute pointers
- which we cannot turn into PC relative,
- don't create the binary search table,
- since it is affected by runtime relocations. */
- hdr_info->table = FALSE;
- (*info->callbacks->einfo)
- (_("%P: fde encoding in %B(%A) prevents .eh_frame_hdr"
- " table being created.\n"), abfd, sec);
+ REQUIRE (rsec->owner == abfd);
+ this_inf->u.fde.next_for_section = elf_fde_list (rsec);
+ elf_fde_list (rsec) = this_inf;
}
- ecie->usage_count++;
- hdr_info->fde_count++;
- this_inf->cie_inf = (void *) (ecie - ecies);
}
/* Skip the initial location and address range. */
length = get_DW_EH_PE_width (cie->fde_encoding, ptr_size);
REQUIRE (skip_bytes (&buf, end, 2 * length));
+ SKIP_RELOCS (buf - length);
+ if (!GET_RELOC (buf - length)
+ && read_value (abfd, buf - length, length, FALSE) == 0)
+ {
+ (*info->callbacks->minfo)
+ /* xgettext:c-format */
+ (_("discarding zero address range FDE in %pB(%pA).\n"),
+ abfd, sec);
+ this_inf->u.fde.cie_inf = NULL;
+ }
+
/* Skip the augmentation size, if present. */
if (cie->augmentation[0] == 'z')
REQUIRE (read_uleb128 (&buf, end, &length));
be adjusted if any future augmentations do the same thing. */
if (cie->lsda_encoding != DW_EH_PE_omit)
{
+ SKIP_RELOCS (buf);
+ if (cie->can_make_lsda_relative && GET_RELOC (buf))
+ cie->cie_inf->u.cie.make_lsda_relative = 1;
this_inf->lsda_offset = buf - start;
/* If there's no 'z' augmentation, we don't know where the
CFA insns begin. Assume no padding. */
insns = buf;
buf = last_fde + 4 + hdr_length;
+
+ /* For NULL RSEC (cleared FDE belonging to a discarded section)
+ the relocations are commonly cleared. We do not sanity check if
+ all these relocations are cleared as (1) relocations to
+ .gcc_except_table will remain uncleared (they will get dropped
+ with the drop of this unused FDE) and (2) BFD already safely drops
+ relocations of any type to .eh_frame by
+ elf_section_ignore_discarded_relocs.
+ TODO: The .gcc_except_table entries should be also filtered as
+ .eh_frame entries; or GCC could rather use COMDAT for them. */
SKIP_RELOCS (buf);
}
cie->length -= end - insns_end;
}
if (set_loc_count
- && ((cie->fde_encoding & 0xf0) == DW_EH_PE_pcrel
- || cie->make_relative))
+ && ((cie->fde_encoding & 0x70) == DW_EH_PE_pcrel
+ || this_inf->make_relative))
{
unsigned int cnt;
bfd_byte *p;
- this_inf->set_loc = bfd_malloc ((set_loc_count + 1)
- * sizeof (unsigned int));
- REQUIRE (this_inf->set_loc);
- this_inf->set_loc[0] = set_loc_count;
- p = insns;
- cnt = 0;
- while (p < end)
- {
- if (*p == DW_CFA_set_loc)
- this_inf->set_loc[++cnt] = p + 1 - start;
- REQUIRE (skip_cfa_op (&p, end, length));
- }
- }
+ this_inf->set_loc = (unsigned int *)
+ bfd_malloc ((set_loc_count + 1) * sizeof (unsigned int));
+ REQUIRE (this_inf->set_loc);
+ this_inf->set_loc[0] = set_loc_count;
+ p = insns;
+ cnt = 0;
+ while (p < end)
+ {
+ if (*p == DW_CFA_set_loc)
+ this_inf->set_loc[++cnt] = p + 1 - start;
+ REQUIRE (skip_cfa_op (&p, end, length));
+ }
+ }
+
+ this_inf->removed = 1;
+ this_inf->fde_encoding = cie->fde_encoding;
+ this_inf->lsda_encoding = cie->lsda_encoding;
+ sec_info->count++;
+ }
+ BFD_ASSERT (sec_info->count == num_entries);
+ BFD_ASSERT (cie_count == num_cies);
+
+ elf_section_data (sec)->sec_info = sec_info;
+ sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME;
+ if (!bfd_link_relocatable (info))
+ {
+ /* Keep info for merging cies. */
+ sec_info->cies = local_cies;
+ local_cies = NULL;
+ }
+ goto success;
+
+ free_no_table:
+ _bfd_error_handler
+ /* xgettext:c-format */
+ (_("error in %pB(%pA); no .eh_frame_hdr table will be created"),
+ abfd, sec);
+ hdr_info->u.dwarf.table = FALSE;
+ free (sec_info);
+ success:
+ free (ehbuf);
+ free (local_cies);
+#undef REQUIRE
+}
+
+/* Order eh_frame_hdr entries by the VMA of their text section. */
+
+static int
+cmp_eh_frame_hdr (const void *a, const void *b)
+{
+ bfd_vma text_a;
+ bfd_vma text_b;
+ asection *sec;
+
+ sec = *(asection *const *)a;
+ sec = (asection *) elf_section_data (sec)->sec_info;
+ text_a = sec->output_section->vma + sec->output_offset;
+ sec = *(asection *const *)b;
+ sec = (asection *) elf_section_data (sec)->sec_info;
+ text_b = sec->output_section->vma + sec->output_offset;
+
+ if (text_a < text_b)
+ return -1;
+ return text_a > text_b;
+
+}
+
+/* Add space for a CANTUNWIND terminator to SEC if the text sections
+ referenced by it and NEXT are not contiguous, or NEXT is NULL. */
+
+static void
+add_eh_frame_hdr_terminator (asection *sec,
+ asection *next)
+{
+ bfd_vma end;
+ bfd_vma next_start;
+ asection *text_sec;
+
+ if (next)
+ {
+ /* See if there is a gap (presumably a text section without unwind info)
+ between these two entries. */
+ text_sec = (asection *) elf_section_data (sec)->sec_info;
+ end = text_sec->output_section->vma + text_sec->output_offset
+ + text_sec->size;
+ text_sec = (asection *) elf_section_data (next)->sec_info;
+ next_start = text_sec->output_section->vma + text_sec->output_offset;
+ if (end == next_start)
+ return;
+ }
+
+ /* Add space for a CANTUNWIND terminator. */
+ if (!sec->rawsize)
+ sec->rawsize = sec->size;
+
+ bfd_set_section_size (sec, sec->size + 8);
+}
+
+/* Finish a pass over all .eh_frame_entry sections. */
+
+bfd_boolean
+_bfd_elf_end_eh_frame_parsing (struct bfd_link_info *info)
+{
+ struct eh_frame_hdr_info *hdr_info;
+ unsigned int i;
+
+ hdr_info = &elf_hash_table (info)->eh_info;
+
+ if (info->eh_frame_hdr_type != COMPACT_EH_HDR
+ || hdr_info->array_count == 0)
+ return FALSE;
+
+ bfd_elf_discard_eh_frame_entry (hdr_info);
+
+ qsort (hdr_info->u.compact.entries, hdr_info->array_count,
+ sizeof (asection *), cmp_eh_frame_hdr);
+
+ for (i = 0; i < hdr_info->array_count - 1; i++)
+ {
+ add_eh_frame_hdr_terminator (hdr_info->u.compact.entries[i],
+ hdr_info->u.compact.entries[i + 1]);
+ }
+
+ /* Add a CANTUNWIND terminator after the last entry. */
+ add_eh_frame_hdr_terminator (hdr_info->u.compact.entries[i], NULL);
+ return TRUE;
+}
+
+/* Mark all relocations against CIE or FDE ENT, which occurs in
+ .eh_frame section SEC. COOKIE describes the relocations in SEC;
+ its "rel" field can be changed freely. */
+
+static bfd_boolean
+mark_entry (struct bfd_link_info *info, asection *sec,
+ struct eh_cie_fde *ent, elf_gc_mark_hook_fn gc_mark_hook,
+ struct elf_reloc_cookie *cookie)
+{
+ /* FIXME: octets_per_byte. */
+ for (cookie->rel = cookie->rels + ent->reloc_index;
+ cookie->rel < cookie->relend
+ && cookie->rel->r_offset < ent->offset + ent->size;
+ cookie->rel++)
+ if (!_bfd_elf_gc_mark_reloc (info, sec, gc_mark_hook, cookie))
+ return FALSE;
+
+ return TRUE;
+}
+
+/* Mark all the relocations against FDEs that relate to code in input
+ section SEC. The FDEs belong to .eh_frame section EH_FRAME, whose
+ relocations are described by COOKIE. */
+
+bfd_boolean
+_bfd_elf_gc_mark_fdes (struct bfd_link_info *info, asection *sec,
+ asection *eh_frame, elf_gc_mark_hook_fn gc_mark_hook,
+ struct elf_reloc_cookie *cookie)
+{
+ struct eh_cie_fde *fde, *cie;
+
+ for (fde = elf_fde_list (sec); fde; fde = fde->u.fde.next_for_section)
+ {
+ if (!mark_entry (info, eh_frame, fde, gc_mark_hook, cookie))
+ return FALSE;
+
+ /* At this stage, all cie_inf fields point to local CIEs, so we
+ can use the same cookie to refer to them. */
+ cie = fde->u.fde.cie_inf;
+ if (cie != NULL && !cie->u.cie.gc_mark)
+ {
+ cie->u.cie.gc_mark = 1;
+ if (!mark_entry (info, eh_frame, cie, gc_mark_hook, cookie))
+ return FALSE;
+ }
+ }
+ return TRUE;
+}
+
+/* Input section SEC of ABFD is an .eh_frame section that contains the
+ CIE described by CIE_INF. Return a version of CIE_INF that is going
+ to be kept in the output, adding CIE_INF to the output if necessary.
+
+ HDR_INFO is the .eh_frame_hdr information and COOKIE describes the
+ relocations in REL. */
+
+static struct eh_cie_fde *
+find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec,
+ struct eh_frame_hdr_info *hdr_info,
+ struct elf_reloc_cookie *cookie,
+ struct eh_cie_fde *cie_inf)
+{
+ unsigned long r_symndx;
+ struct cie *cie, *new_cie;
+ Elf_Internal_Rela *rel;
+ void **loc;
+
+ /* Use CIE_INF if we have already decided to keep it. */
+ if (!cie_inf->removed)
+ return cie_inf;
+
+ /* If we have merged CIE_INF with another CIE, use that CIE instead. */
+ if (cie_inf->u.cie.merged)
+ return cie_inf->u.cie.u.merged_with;
+
+ cie = cie_inf->u.cie.u.full_cie;
+
+ /* Assume we will need to keep CIE_INF. */
+ cie_inf->removed = 0;
+ cie_inf->u.cie.u.sec = sec;
+
+ /* If we are not merging CIEs, use CIE_INF. */
+ if (cie == NULL)
+ return cie_inf;
+
+ if (cie->per_encoding != DW_EH_PE_omit)
+ {
+ bfd_boolean per_binds_local;
+
+ /* Work out the address of personality routine, or at least
+ enough info that we could calculate the address had we made a
+ final section layout. The symbol on the reloc is enough,
+ either the hash for a global, or (bfd id, index) pair for a
+ local. The assumption here is that no one uses addends on
+ the reloc. */
+ rel = cookie->rels + cie->personality.reloc_index;
+ memset (&cie->personality, 0, sizeof (cie->personality));
+#ifdef BFD64
+ if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64)
+ r_symndx = ELF64_R_SYM (rel->r_info);
+ else
+#endif
+ r_symndx = ELF32_R_SYM (rel->r_info);
+ if (r_symndx >= cookie->locsymcount
+ || ELF_ST_BIND (cookie->locsyms[r_symndx].st_info) != STB_LOCAL)
+ {
+ struct elf_link_hash_entry *h;
+
+ r_symndx -= cookie->extsymoff;
+ h = cookie->sym_hashes[r_symndx];
+
+ while (h->root.type == bfd_link_hash_indirect
+ || h->root.type == bfd_link_hash_warning)
+ h = (struct elf_link_hash_entry *) h->root.u.i.link;
+
+ cie->personality.h = h;
+ per_binds_local = SYMBOL_REFERENCES_LOCAL (info, h);
+ }
+ else
+ {
+ Elf_Internal_Sym *sym;
+ asection *sym_sec;
+
+ sym = &cookie->locsyms[r_symndx];
+ sym_sec = bfd_section_from_elf_index (abfd, sym->st_shndx);
+ if (sym_sec == NULL)
+ return cie_inf;
+
+ if (sym_sec->kept_section != NULL)
+ sym_sec = sym_sec->kept_section;
+ if (sym_sec->output_section == NULL)
+ return cie_inf;
+
+ cie->local_personality = 1;
+ cie->personality.sym.bfd_id = abfd->id;
+ cie->personality.sym.index = r_symndx;
+ per_binds_local = TRUE;
+ }
+
+ if (per_binds_local
+ && bfd_link_pic (info)
+ && (cie->per_encoding & 0x70) == DW_EH_PE_absptr
+ && (get_elf_backend_data (abfd)
+ ->elf_backend_can_make_relative_eh_frame (abfd, info, sec)))
+ {
+ cie_inf->u.cie.make_per_encoding_relative = 1;
+ cie_inf->u.cie.per_encoding_relative = 1;
+ }
+ }
+
+ /* See if we can merge this CIE with an earlier one. */
+ cie_compute_hash (cie);
+ if (hdr_info->u.dwarf.cies == NULL)
+ {
+ hdr_info->u.dwarf.cies = htab_try_create (1, cie_hash, cie_eq, free);
+ if (hdr_info->u.dwarf.cies == NULL)
+ return cie_inf;
+ }
+ loc = htab_find_slot_with_hash (hdr_info->u.dwarf.cies, cie,
+ cie->hash, INSERT);
+ if (loc == NULL)
+ return cie_inf;
+
+ new_cie = (struct cie *) *loc;
+ if (new_cie == NULL)
+ {
+ /* Keep CIE_INF and record it in the hash table. */
+ new_cie = (struct cie *) malloc (sizeof (struct cie));
+ if (new_cie == NULL)
+ return cie_inf;
+
+ memcpy (new_cie, cie, sizeof (struct cie));
+ *loc = new_cie;
+ }
+ else
+ {
+ /* Merge CIE_INF with NEW_CIE->CIE_INF. */
+ cie_inf->removed = 1;
+ cie_inf->u.cie.merged = 1;
+ cie_inf->u.cie.u.merged_with = new_cie->cie_inf;
+ if (cie_inf->u.cie.make_lsda_relative)
+ new_cie->cie_inf->u.cie.make_lsda_relative = 1;
+ }
+ return new_cie->cie_inf;
+}
+
+/* For a given OFFSET in SEC, return the delta to the new location
+ after .eh_frame editing. */
+
+static bfd_signed_vma
+offset_adjust (bfd_vma offset, const asection *sec)
+{
+ struct eh_frame_sec_info *sec_info
+ = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info;
+ unsigned int lo, hi, mid;
+ struct eh_cie_fde *ent = NULL;
+ bfd_signed_vma delta;
+
+ lo = 0;
+ hi = sec_info->count;
+ if (hi == 0)
+ return 0;
+
+ while (lo < hi)
+ {
+ mid = (lo + hi) / 2;
+ ent = &sec_info->entry[mid];
+ if (offset < ent->offset)
+ hi = mid;
+ else if (mid + 1 >= hi)
+ break;
+ else if (offset >= ent[1].offset)
+ lo = mid + 1;
+ else
+ break;
+ }
+
+ if (!ent->removed)
+ delta = (bfd_vma) ent->new_offset - (bfd_vma) ent->offset;
+ else if (ent->cie && ent->u.cie.merged)
+ {
+ struct eh_cie_fde *cie = ent->u.cie.u.merged_with;
+ delta = ((bfd_vma) cie->new_offset + cie->u.cie.u.sec->output_offset
+ - (bfd_vma) ent->offset - sec->output_offset);
+ }
+ else
+ {
+ /* Is putting the symbol on the next entry best for a deleted
+ CIE/FDE? */
+ struct eh_cie_fde *last = sec_info->entry + sec_info->count;
+ delta = ((bfd_vma) next_cie_fde_offset (ent, last, sec)
+ - (bfd_vma) ent->offset);
+ return delta;
+ }
+
+ /* Account for editing within this CIE/FDE. */
+ offset -= ent->offset;
+ if (ent->cie)
+ {
+ unsigned int extra
+ = ent->add_augmentation_size + ent->u.cie.add_fde_encoding;
+ if (extra == 0
+ || offset <= 9u + ent->u.cie.aug_str_len)
+ return delta;
+ delta += extra;
+ if (offset <= 9u + ent->u.cie.aug_str_len + ent->u.cie.aug_data_len)
+ return delta;
+ delta += extra;
+ }
+ else
+ {
+ unsigned int ptr_size, width, extra = ent->add_augmentation_size;
+ if (offset <= 12 || extra == 0)
+ return delta;
+ ptr_size = (get_elf_backend_data (sec->owner)
+ ->elf_backend_eh_frame_address_size (sec->owner, sec));
+ width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
+ if (offset <= 8 + 2 * width)
+ return delta;
+ delta += extra;
+ }
+
+ return delta;
+}
+
+/* Adjust a global symbol defined in .eh_frame, so that it stays
+ relative to its original CIE/FDE. It is assumed that a symbol
+ defined at the beginning of a CIE/FDE belongs to that CIE/FDE
+ rather than marking the end of the previous CIE/FDE. This matters
+ when a CIE is merged with a previous CIE, since the symbol is
+ moved to the merged CIE. */
+
+bfd_boolean
+_bfd_elf_adjust_eh_frame_global_symbol (struct elf_link_hash_entry *h,
+ void *arg ATTRIBUTE_UNUSED)
+{
+ asection *sym_sec;
+ bfd_signed_vma delta;
+
+ if (h->root.type != bfd_link_hash_defined
+ && h->root.type != bfd_link_hash_defweak)
+ return TRUE;
+
+ sym_sec = h->root.u.def.section;
+ if (sym_sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME
+ || elf_section_data (sym_sec)->sec_info == NULL)
+ return TRUE;
+
+ delta = offset_adjust (h->root.u.def.value, sym_sec);
+ h->root.u.def.value += delta;
+
+ return TRUE;
+}
+
+/* The same for all local symbols defined in .eh_frame. Returns true
+ if any symbol was changed. */
+
+static int
+adjust_eh_frame_local_symbols (const asection *sec,
+ struct elf_reloc_cookie *cookie)
+{
+ unsigned int shndx;
+ Elf_Internal_Sym *sym;
+ Elf_Internal_Sym *end_sym;
+ int adjusted = 0;
+
+ shndx = elf_section_data (sec)->this_idx;
+ end_sym = cookie->locsyms + cookie->locsymcount;
+ for (sym = cookie->locsyms + 1; sym < end_sym; ++sym)
+ if (sym->st_info <= ELF_ST_INFO (STB_LOCAL, STT_OBJECT)
+ && sym->st_shndx == shndx)
+ {
+ bfd_signed_vma delta = offset_adjust (sym->st_value, sec);
+
+ if (delta != 0)
+ {
+ adjusted = 1;
+ sym->st_value += delta;
+ }
+ }
+ return adjusted;
+}
- this_inf->fde_encoding = cie->fde_encoding;
- this_inf->lsda_encoding = cie->lsda_encoding;
- sec_info->count++;
- }
+/* This function is called for each input file before the .eh_frame
+ section is relocated. It discards duplicate CIEs and FDEs for discarded
+ functions. The function returns TRUE iff any entries have been
+ deleted. */
- elf_section_data (sec)->sec_info = sec_info;
- sec->sec_info_type = ELF_INFO_TYPE_EH_FRAME;
+bfd_boolean
+_bfd_elf_discard_section_eh_frame
+ (bfd *abfd, struct bfd_link_info *info, asection *sec,
+ bfd_boolean (*reloc_symbol_deleted_p) (bfd_vma, void *),
+ struct elf_reloc_cookie *cookie)
+{
+ struct eh_cie_fde *ent;
+ struct eh_frame_sec_info *sec_info;
+ struct eh_frame_hdr_info *hdr_info;
+ unsigned int ptr_size, offset, eh_alignment;
+ int changed;
- /* Look at all CIEs in this section and determine which can be
- removed as unused, which can be merged with previous duplicate
- CIEs and which need to be kept. */
- for (ecie = ecies; ecie < ecies + ecie_count; ++ecie)
- {
- if (ecie->usage_count == 0)
- {
- sec_info->entry[ecie->entry].removed = 1;
- continue;
- }
- ecie->cie.output_sec = sec->output_section;
- ecie->cie.cie_inf = sec_info->entry + ecie->entry;
- cie_compute_hash (&ecie->cie);
- if (hdr_info->cies != NULL)
- {
- void **loc = htab_find_slot_with_hash (hdr_info->cies, &ecie->cie,
- ecie->cie.hash, INSERT);
- if (loc != NULL)
- {
- if (*loc != HTAB_EMPTY_ENTRY)
- {
- sec_info->entry[ecie->entry].removed = 1;
- ecie->cie.cie_inf = ((struct cie *) *loc)->cie_inf;
- continue;
- }
+ if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME)
+ return FALSE;
- *loc = malloc (sizeof (struct cie));
- if (*loc == NULL)
- *loc = HTAB_DELETED_ENTRY;
- else
- memcpy (*loc, &ecie->cie, sizeof (struct cie));
- }
- }
- ecie->cie.cie_inf->make_relative = ecie->cie.make_relative;
- ecie->cie.cie_inf->make_lsda_relative = ecie->cie.make_lsda_relative;
- ecie->cie.cie_inf->per_encoding_relative
- = (ecie->cie.per_encoding & 0x70) == DW_EH_PE_pcrel;
- }
+ sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info;
+ if (sec_info == NULL)
+ return FALSE;
+
+ ptr_size = (get_elf_backend_data (sec->owner)
+ ->elf_backend_eh_frame_address_size (sec->owner, sec));
+
+ hdr_info = &elf_hash_table (info)->eh_info;
+ for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent)
+ if (ent->size == 4)
+ /* There should only be one zero terminator, on the last input
+ file supplying .eh_frame (crtend.o). Remove any others. */
+ ent->removed = sec->map_head.s != NULL;
+ else if (!ent->cie && ent->u.fde.cie_inf != NULL)
+ {
+ bfd_boolean keep;
+ if ((sec->flags & SEC_LINKER_CREATED) != 0 && cookie->rels == NULL)
+ {
+ unsigned int width
+ = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
+ bfd_vma value
+ = read_value (abfd, sec->contents + ent->offset + 8 + width,
+ width, get_DW_EH_PE_signed (ent->fde_encoding));
+ keep = value != 0;
+ }
+ else
+ {
+ cookie->rel = cookie->rels + ent->reloc_index;
+ /* FIXME: octets_per_byte. */
+ BFD_ASSERT (cookie->rel < cookie->relend
+ && cookie->rel->r_offset == ent->offset + 8);
+ keep = !(*reloc_symbol_deleted_p) (ent->offset + 8, cookie);
+ }
+ if (keep)
+ {
+ if (bfd_link_pic (info)
+ && (((ent->fde_encoding & 0x70) == DW_EH_PE_absptr
+ && ent->make_relative == 0)
+ || (ent->fde_encoding & 0x70) == DW_EH_PE_aligned))
+ {
+ static int num_warnings_issued = 0;
+
+ /* If a shared library uses absolute pointers
+ which we cannot turn into PC relative,
+ don't create the binary search table,
+ since it is affected by runtime relocations. */
+ hdr_info->u.dwarf.table = FALSE;
+ /* Only warn if --eh-frame-hdr was specified. */
+ if (info->eh_frame_hdr_type != 0)
+ {
+ if (num_warnings_issued < 10)
+ {
+ _bfd_error_handler
+ /* xgettext:c-format */
+ (_("FDE encoding in %pB(%pA) prevents .eh_frame_hdr"
+ " table being created"), abfd, sec);
+ num_warnings_issued ++;
+ }
+ else if (num_warnings_issued == 10)
+ {
+ _bfd_error_handler
+ (_("further warnings about FDE encoding preventing .eh_frame_hdr generation dropped"));
+ num_warnings_issued ++;
+ }
+ }
+ }
+ ent->removed = 0;
+ hdr_info->u.dwarf.fde_count++;
+ ent->u.fde.cie_inf = find_merged_cie (abfd, info, sec, hdr_info,
+ cookie, ent->u.fde.cie_inf);
+ }
+ }
- /* Ok, now we can assign new offsets. */
+ free (sec_info->cies);
+ sec_info->cies = NULL;
+
+ /* It may be that some .eh_frame input section has greater alignment
+ than other .eh_frame sections. In that case we run the risk of
+ padding with zeros before that section, which would be seen as a
+ zero terminator. Alignment padding must be added *inside* the
+ last FDE instead. For other FDEs we align according to their
+ encoding, in order to align FDE address range entries naturally. */
offset = 0;
+ changed = 0;
for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent)
if (!ent->removed)
{
- if (!ent->cie)
+ eh_alignment = 4;
+ if (ent->size == 4)
+ ;
+ else if (ent->cie)
+ {
+ if (ent->u.cie.per_encoding_aligned8)
+ eh_alignment = 8;
+ }
+ else
{
- ecie = ecies + (unsigned long) ent->cie_inf;
- ent->cie_inf = ecie->cie.cie_inf;
+ eh_alignment = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
+ if (eh_alignment < 4)
+ eh_alignment = 4;
}
+ offset = (offset + eh_alignment - 1) & -eh_alignment;
ent->new_offset = offset;
- offset += size_of_output_cie_fde (ent, ptr_size);
+ if (ent->new_offset != ent->offset)
+ changed = 1;
+ offset += size_of_output_cie_fde (ent);
}
- /* Resize the sec as needed. */
+ eh_alignment = 4;
+ offset = (offset + eh_alignment - 1) & -eh_alignment;
sec->rawsize = sec->size;
sec->size = offset;
+ if (sec->size != sec->rawsize)
+ changed = 1;
- free (ehbuf);
- if (ecies)
- free (ecies);
- return offset != sec->rawsize;
-
-free_no_table:
- (*info->callbacks->einfo)
- (_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"),
- abfd, sec);
- if (ehbuf)
- free (ehbuf);
- if (sec_info)
- free (sec_info);
- if (ecies)
- free (ecies);
- hdr_info->table = FALSE;
- return FALSE;
-
-#undef REQUIRE
+ if (changed && adjust_eh_frame_local_symbols (sec, cookie))
+ {
+ Elf_Internal_Shdr *symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
+ symtab_hdr->contents = (unsigned char *) cookie->locsyms;
+ }
+ return changed;
}
/* This function is called for .eh_frame_hdr section after
htab = elf_hash_table (info);
hdr_info = &htab->eh_info;
- if (hdr_info->cies != NULL)
+ if (!hdr_info->frame_hdr_is_compact && hdr_info->u.dwarf.cies != NULL)
{
- htab_delete (hdr_info->cies);
- hdr_info->cies = NULL;
+ htab_delete (hdr_info->u.dwarf.cies);
+ hdr_info->u.dwarf.cies = NULL;
}
sec = hdr_info->hdr_sec;
if (sec == NULL)
return FALSE;
- sec->size = EH_FRAME_HDR_SIZE;
- if (hdr_info->table)
- sec->size += 4 + hdr_info->fde_count * 8;
+ if (info->eh_frame_hdr_type == COMPACT_EH_HDR)
+ {
+ /* For compact frames we only add the header. The actual table comes
+ from the .eh_frame_entry sections. */
+ sec->size = 8;
+ }
+ else
+ {
+ sec->size = EH_FRAME_HDR_SIZE;
+ if (hdr_info->u.dwarf.table)
+ sec->size += 4 + hdr_info->u.dwarf.fde_count * 8;
+ }
- elf_tdata (abfd)->eh_frame_hdr = sec;
+ elf_eh_frame_hdr (abfd) = sec;
return TRUE;
}
+/* Return true if there is at least one non-empty .eh_frame section in
+ input files. Can only be called after ld has mapped input to
+ output sections, and before sections are stripped. */
+
+bfd_boolean
+_bfd_elf_eh_frame_present (struct bfd_link_info *info)
+{
+ asection *eh = bfd_get_section_by_name (info->output_bfd, ".eh_frame");
+
+ if (eh == NULL)
+ return FALSE;
+
+ /* Count only sections which have at least a single CIE or FDE.
+ There cannot be any CIE or FDE <= 8 bytes. */
+ for (eh = eh->map_head.s; eh != NULL; eh = eh->map_head.s)
+ if (eh->size > 8)
+ return TRUE;
+
+ return FALSE;
+}
+
+/* Return true if there is at least one .eh_frame_entry section in
+ input files. */
+
+bfd_boolean
+_bfd_elf_eh_frame_entry_present (struct bfd_link_info *info)
+{
+ asection *o;
+ bfd *abfd;
+
+ for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link.next)
+ {
+ for (o = abfd->sections; o; o = o->next)
+ {
+ const char *name = bfd_section_name (o);
+
+ if (strcmp (name, ".eh_frame_entry")
+ && !bfd_is_abs_section (o->output_section))
+ return TRUE;
+ }
+ }
+ return FALSE;
+}
+
/* This function is called from size_dynamic_sections.
It needs to decide whether .eh_frame_hdr should be output or not,
because when the dynamic symbol table has been sized it is too late
bfd_boolean
_bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info)
{
- asection *o;
- bfd *abfd;
struct elf_link_hash_table *htab;
struct eh_frame_hdr_info *hdr_info;
+ struct bfd_link_hash_entry *bh = NULL;
+ struct elf_link_hash_entry *h;
htab = elf_hash_table (info);
hdr_info = &htab->eh_info;
if (hdr_info->hdr_sec == NULL)
return TRUE;
- if (bfd_is_abs_section (hdr_info->hdr_sec->output_section))
+ if (bfd_is_abs_section (hdr_info->hdr_sec->output_section)
+ || info->eh_frame_hdr_type == 0
+ || (info->eh_frame_hdr_type == DWARF2_EH_HDR
+ && !_bfd_elf_eh_frame_present (info))
+ || (info->eh_frame_hdr_type == COMPACT_EH_HDR
+ && !_bfd_elf_eh_frame_entry_present (info)))
{
+ hdr_info->hdr_sec->flags |= SEC_EXCLUDE;
hdr_info->hdr_sec = NULL;
return TRUE;
}
- abfd = NULL;
- if (info->eh_frame_hdr)
- for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
- {
- /* Count only sections which have at least a single CIE or FDE.
- There cannot be any CIE or FDE <= 8 bytes. */
- o = bfd_get_section_by_name (abfd, ".eh_frame");
- if (o && o->size > 8 && !bfd_is_abs_section (o->output_section))
- break;
- }
+ /* Add a hidden symbol so that systems without access to PHDRs can
+ find the table. */
+ if (! (_bfd_generic_link_add_one_symbol
+ (info, info->output_bfd, "__GNU_EH_FRAME_HDR", BSF_LOCAL,
+ hdr_info->hdr_sec, 0, NULL, FALSE, FALSE, &bh)))
+ return FALSE;
- if (abfd == NULL)
- {
- hdr_info->hdr_sec->flags |= SEC_EXCLUDE;
- hdr_info->hdr_sec = NULL;
- return TRUE;
- }
+ h = (struct elf_link_hash_entry *) bh;
+ h->def_regular = 1;
+ h->other = STV_HIDDEN;
+ get_elf_backend_data
+ (info->output_bfd)->elf_backend_hide_symbol (info, h, TRUE);
- hdr_info->table = TRUE;
+ if (!hdr_info->frame_hdr_is_compact)
+ hdr_info->u.dwarf.table = TRUE;
return TRUE;
}
bfd_vma
_bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED,
- struct bfd_link_info *info,
+ struct bfd_link_info *info ATTRIBUTE_UNUSED,
asection *sec,
bfd_vma offset)
{
struct eh_frame_sec_info *sec_info;
- struct elf_link_hash_table *htab;
- struct eh_frame_hdr_info *hdr_info;
unsigned int lo, hi, mid;
- if (sec->sec_info_type != ELF_INFO_TYPE_EH_FRAME)
+ if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME)
return offset;
- sec_info = elf_section_data (sec)->sec_info;
+ sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info;
if (offset >= sec->rawsize)
return offset - sec->rawsize + sec->size;
- htab = elf_hash_table (info);
- hdr_info = &htab->eh_info;
- if (hdr_info->offsets_adjusted)
- offset += sec->output_offset;
-
lo = 0;
hi = sec_info->count;
mid = 0;
if (sec_info->entry[mid].removed)
return (bfd_vma) -1;
+ /* If converting personality pointers to DW_EH_PE_pcrel, there will be
+ no need for run-time relocation against the personality field. */
+ if (sec_info->entry[mid].cie
+ && sec_info->entry[mid].u.cie.make_per_encoding_relative
+ && offset == (sec_info->entry[mid].offset + 8
+ + sec_info->entry[mid].u.cie.personality_offset))
+ return (bfd_vma) -2;
+
/* If converting to DW_EH_PE_pcrel, there will be no need for run-time
relocation against FDE's initial_location field. */
if (!sec_info->entry[mid].cie
- && sec_info->entry[mid].cie_inf->make_relative
+ && sec_info->entry[mid].make_relative
&& offset == sec_info->entry[mid].offset + 8)
return (bfd_vma) -2;
/* If converting LSDA pointers to DW_EH_PE_pcrel, there will be no need
for run-time relocation against LSDA field. */
if (!sec_info->entry[mid].cie
- && sec_info->entry[mid].cie_inf->make_lsda_relative
- && (offset == (sec_info->entry[mid].offset + 8
- + sec_info->entry[mid].lsda_offset))
- && (sec_info->entry[mid].cie_inf->need_lsda_relative
- || !hdr_info->offsets_adjusted))
- {
- sec_info->entry[mid].cie_inf->need_lsda_relative = 1;
- return (bfd_vma) -2;
- }
+ && sec_info->entry[mid].u.fde.cie_inf->u.cie.make_lsda_relative
+ && offset == (sec_info->entry[mid].offset + 8
+ + sec_info->entry[mid].lsda_offset))
+ return (bfd_vma) -2;
/* If converting to DW_EH_PE_pcrel, there will be no need for run-time
relocation against DW_CFA_set_loc's arguments. */
if (sec_info->entry[mid].set_loc
- && (sec_info->entry[mid].cie
- ? sec_info->entry[mid].make_relative
- : sec_info->entry[mid].cie_inf->make_relative)
+ && sec_info->entry[mid].make_relative
&& (offset >= sec_info->entry[mid].offset + 8
+ sec_info->entry[mid].set_loc[1]))
{
return (bfd_vma) -2;
}
- if (hdr_info->offsets_adjusted)
- offset -= sec->output_offset;
/* Any new augmentation bytes go before the first relocation. */
return (offset + sec_info->entry[mid].new_offset
- sec_info->entry[mid].offset
+ extra_augmentation_data_bytes (sec_info->entry + mid));
}
+/* Write out .eh_frame_entry section. Add CANTUNWIND terminator if needed.
+ Also check that the contents look sane. */
+
+bfd_boolean
+_bfd_elf_write_section_eh_frame_entry (bfd *abfd, struct bfd_link_info *info,
+ asection *sec, bfd_byte *contents)
+{
+ const struct elf_backend_data *bed;
+ bfd_byte cantunwind[8];
+ bfd_vma addr;
+ bfd_vma last_addr;
+ bfd_vma offset;
+ asection *text_sec = (asection *) elf_section_data (sec)->sec_info;
+
+ if (!sec->rawsize)
+ sec->rawsize = sec->size;
+
+ BFD_ASSERT (sec->sec_info_type == SEC_INFO_TYPE_EH_FRAME_ENTRY);
+
+ /* Check to make sure that the text section corresponding to this eh_frame_entry
+ section has not been excluded. In particular, mips16 stub entries will be
+ excluded outside of the normal process. */
+ if (sec->flags & SEC_EXCLUDE
+ || text_sec->flags & SEC_EXCLUDE)
+ return TRUE;
+
+ if (!bfd_set_section_contents (abfd, sec->output_section, contents,
+ sec->output_offset, sec->rawsize))
+ return FALSE;
+
+ last_addr = bfd_get_signed_32 (abfd, contents);
+ /* Check that all the entries are in order. */
+ for (offset = 8; offset < sec->rawsize; offset += 8)
+ {
+ addr = bfd_get_signed_32 (abfd, contents + offset) + offset;
+ if (addr <= last_addr)
+ {
+ /* xgettext:c-format */
+ _bfd_error_handler (_("%pB: %pA not in order"), sec->owner, sec);
+ return FALSE;
+ }
+
+ last_addr = addr;
+ }
+
+ addr = text_sec->output_section->vma + text_sec->output_offset
+ + text_sec->size;
+ addr &= ~1;
+ addr -= (sec->output_section->vma + sec->output_offset + sec->rawsize);
+ if (addr & 1)
+ {
+ /* xgettext:c-format */
+ _bfd_error_handler (_("%pB: %pA invalid input section size"),
+ sec->owner, sec);
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+ }
+ if (last_addr >= addr + sec->rawsize)
+ {
+ /* xgettext:c-format */
+ _bfd_error_handler (_("%pB: %pA points past end of text section"),
+ sec->owner, sec);
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+ }
+
+ if (sec->size == sec->rawsize)
+ return TRUE;
+
+ bed = get_elf_backend_data (abfd);
+ BFD_ASSERT (sec->size == sec->rawsize + 8);
+ BFD_ASSERT ((addr & 1) == 0);
+ BFD_ASSERT (bed->cant_unwind_opcode);
+
+ bfd_put_32 (abfd, addr, cantunwind);
+ bfd_put_32 (abfd, (*bed->cant_unwind_opcode) (info), cantunwind + 4);
+ return bfd_set_section_contents (abfd, sec->output_section, cantunwind,
+ sec->output_offset + sec->rawsize, 8);
+}
+
/* Write out .eh_frame section. This is called with the relocated
contents. */
struct elf_link_hash_table *htab;
struct eh_frame_hdr_info *hdr_info;
unsigned int ptr_size;
- struct eh_cie_fde *ent;
+ struct eh_cie_fde *ent, *last_ent;
- if (sec->sec_info_type != ELF_INFO_TYPE_EH_FRAME)
+ if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME)
+ /* FIXME: octets_per_byte. */
return bfd_set_section_contents (abfd, sec->output_section, contents,
sec->output_offset, sec->size);
->elf_backend_eh_frame_address_size (abfd, sec));
BFD_ASSERT (ptr_size != 0);
- sec_info = elf_section_data (sec)->sec_info;
+ sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info;
htab = elf_hash_table (info);
hdr_info = &htab->eh_info;
- /* First convert all offsets to output section offsets, so that a
- CIE offset is valid if the CIE is used by a FDE from some other
- section. This can happen when duplicate CIEs are deleted in
- _bfd_elf_discard_section_eh_frame. We do all sections here because
- this function might not be called on sections in the same order as
- _bfd_elf_discard_section_eh_frame. */
- if (!hdr_info->offsets_adjusted)
+ if (hdr_info->u.dwarf.table && hdr_info->u.dwarf.array == NULL)
{
- bfd *ibfd;
- asection *eh;
- struct eh_frame_sec_info *eh_inf;
-
- for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
- {
- if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour
- || (ibfd->flags & DYNAMIC) != 0)
- continue;
-
- eh = bfd_get_section_by_name (ibfd, ".eh_frame");
- if (eh == NULL || eh->sec_info_type != ELF_INFO_TYPE_EH_FRAME)
- continue;
-
- eh_inf = elf_section_data (eh)->sec_info;
- for (ent = eh_inf->entry; ent < eh_inf->entry + eh_inf->count; ++ent)
- {
- ent->offset += eh->output_offset;
- ent->new_offset += eh->output_offset;
- }
- }
- hdr_info->offsets_adjusted = TRUE;
+ hdr_info->frame_hdr_is_compact = FALSE;
+ hdr_info->u.dwarf.array = (struct eh_frame_array_ent *)
+ bfd_malloc (hdr_info->u.dwarf.fde_count
+ * sizeof (*hdr_info->u.dwarf.array));
}
-
- if (hdr_info->table && hdr_info->array == NULL)
- hdr_info->array
- = bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array));
- if (hdr_info->array == NULL)
+ if (hdr_info->u.dwarf.array == NULL)
hdr_info = NULL;
/* The new offsets can be bigger or smaller than the original offsets.
not reordered */
for (ent = sec_info->entry + sec_info->count; ent-- != sec_info->entry;)
if (!ent->removed && ent->new_offset > ent->offset)
- memmove (contents + ent->new_offset - sec->output_offset,
- contents + ent->offset - sec->output_offset, ent->size);
+ memmove (contents + ent->new_offset, contents + ent->offset, ent->size);
for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent)
if (!ent->removed && ent->new_offset < ent->offset)
- memmove (contents + ent->new_offset - sec->output_offset,
- contents + ent->offset - sec->output_offset, ent->size);
+ memmove (contents + ent->new_offset, contents + ent->offset, ent->size);
- for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent)
+ last_ent = sec_info->entry + sec_info->count;
+ for (ent = sec_info->entry; ent < last_ent; ++ent)
{
unsigned char *buf, *end;
unsigned int new_size;
if (ent->size == 4)
{
/* Any terminating FDE must be at the end of the section. */
- BFD_ASSERT (ent == sec_info->entry + sec_info->count - 1);
+ BFD_ASSERT (ent == last_ent - 1);
continue;
}
- buf = contents + ent->new_offset - sec->output_offset;
+ buf = contents + ent->new_offset;
end = buf + ent->size;
- new_size = size_of_output_cie_fde (ent, ptr_size);
+ new_size = next_cie_fde_offset (ent, last_ent, sec) - ent->new_offset;
/* Update the size. It may be shrinked. */
bfd_put_32 (abfd, new_size - 4, buf);
{
/* CIE */
if (ent->make_relative
- || ent->need_lsda_relative
- || ent->per_encoding_relative)
+ || ent->u.cie.make_lsda_relative
+ || ent->u.cie.per_encoding_relative)
{
char *aug;
- unsigned int action, extra_string, extra_data;
+ unsigned int version, action, extra_string, extra_data;
unsigned int per_width, per_encoding;
/* Need to find 'R' or 'L' augmentation's argument and modify
DW_EH_PE_* value. */
action = ((ent->make_relative ? 1 : 0)
- | (ent->need_lsda_relative ? 2 : 0)
- | (ent->per_encoding_relative ? 4 : 0));
+ | (ent->u.cie.make_lsda_relative ? 2 : 0)
+ | (ent->u.cie.per_encoding_relative ? 4 : 0));
extra_string = extra_augmentation_string_bytes (ent);
extra_data = extra_augmentation_data_bytes (ent);
- /* Skip length, id and version. */
- buf += 9;
+ /* Skip length, id. */
+ buf += 8;
+ version = *buf++;
aug = (char *) buf;
buf += strlen (aug) + 1;
skip_leb128 (&buf, end);
skip_leb128 (&buf, end);
- skip_leb128 (&buf, end);
+ if (version == 1)
+ skip_bytes (&buf, end, 1);
+ else
+ skip_leb128 (&buf, end);
if (*aug == 'z')
{
/* The uleb128 will always be a single byte for the kind
*aug++ = 'z';
*buf++ = extra_data - 1;
}
- if (ent->add_fde_encoding)
+ if (ent->u.cie.add_fde_encoding)
{
BFD_ASSERT (action & 1);
*aug++ = 'R';
- *buf++ = DW_EH_PE_pcrel;
+ *buf++ = make_pc_relative (DW_EH_PE_absptr, ptr_size);
action &= ~1;
}
if (action & 2)
{
BFD_ASSERT (*buf == ent->lsda_encoding);
- *buf |= DW_EH_PE_pcrel;
+ *buf = make_pc_relative (*buf, ptr_size);
action &= ~2;
}
buf++;
break;
case 'P':
+ if (ent->u.cie.make_per_encoding_relative)
+ *buf = make_pc_relative (*buf, ptr_size);
per_encoding = *buf++;
per_width = get_DW_EH_PE_width (per_encoding, ptr_size);
BFD_ASSERT (per_width != 0);
BFD_ASSERT (((per_encoding & 0x70) == DW_EH_PE_pcrel)
- == ent->per_encoding_relative);
- if ((per_encoding & 0xf0) == DW_EH_PE_aligned)
+ == ent->u.cie.per_encoding_relative);
+ if ((per_encoding & 0x70) == DW_EH_PE_aligned)
buf = (contents
+ ((buf - contents + per_width - 1)
& ~((bfd_size_type) per_width - 1)));
val = read_value (abfd, buf, per_width,
get_DW_EH_PE_signed (per_encoding));
- val += ent->offset - ent->new_offset;
- val -= extra_string + extra_data;
+ if (ent->u.cie.make_per_encoding_relative)
+ val -= (sec->output_section->vma
+ + sec->output_offset
+ + (buf - contents));
+ else
+ {
+ val += (bfd_vma) ent->offset - ent->new_offset;
+ val -= extra_string + extra_data;
+ }
write_value (abfd, buf, val, per_width);
action &= ~4;
}
if (action & 1)
{
BFD_ASSERT (*buf == ent->fde_encoding);
- *buf |= DW_EH_PE_pcrel;
+ *buf = make_pc_relative (*buf, ptr_size);
action &= ~1;
}
buf++;
bfd_vma value, address;
unsigned int width;
bfd_byte *start;
+ struct eh_cie_fde *cie;
/* Skip length. */
+ cie = ent->u.fde.cie_inf;
buf += 4;
- value = ent->new_offset + 4 - ent->cie_inf->new_offset;
+ value = ((ent->new_offset + sec->output_offset + 4)
+ - (cie->new_offset + cie->u.cie.u.sec->output_offset));
bfd_put_32 (abfd, value, buf);
+ if (bfd_link_relocatable (info))
+ continue;
buf += 4;
width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
value = read_value (abfd, buf, width,
address = value;
if (value)
{
- switch (ent->fde_encoding & 0xf0)
+ switch (ent->fde_encoding & 0x70)
{
- case DW_EH_PE_indirect:
case DW_EH_PE_textrel:
BFD_ASSERT (hdr_info == NULL);
break;
case DW_EH_PE_datarel:
{
- asection *got = bfd_get_section_by_name (abfd, ".got");
-
- BFD_ASSERT (got != NULL);
- address += got->vma;
+ switch (abfd->arch_info->arch)
+ {
+ case bfd_arch_ia64:
+ BFD_ASSERT (elf_gp (abfd) != 0);
+ address += elf_gp (abfd);
+ break;
+ default:
+ _bfd_error_handler
+ (_("DW_EH_PE_datarel unspecified"
+ " for this architecture"));
+ /* Fall thru */
+ case bfd_arch_frv:
+ case bfd_arch_i386:
+ case bfd_arch_nios2:
+ BFD_ASSERT (htab->hgot != NULL
+ && ((htab->hgot->root.type
+ == bfd_link_hash_defined)
+ || (htab->hgot->root.type
+ == bfd_link_hash_defweak)));
+ address
+ += (htab->hgot->root.u.def.value
+ + htab->hgot->root.u.def.section->output_offset
+ + (htab->hgot->root.u.def.section->output_section
+ ->vma));
+ break;
+ }
}
break;
case DW_EH_PE_pcrel:
- value += ent->offset - ent->new_offset;
- address += sec->output_section->vma + ent->offset + 8;
+ value += (bfd_vma) ent->offset - ent->new_offset;
+ address += (sec->output_section->vma
+ + sec->output_offset
+ + ent->offset + 8);
break;
}
- if (ent->cie_inf->make_relative)
- value -= sec->output_section->vma + ent->new_offset + 8;
+ if (ent->make_relative)
+ value -= (sec->output_section->vma
+ + sec->output_offset
+ + ent->new_offset + 8);
write_value (abfd, buf, value, width);
}
if (hdr_info)
{
- hdr_info->array[hdr_info->array_count].initial_loc = address;
- hdr_info->array[hdr_info->array_count++].fde
- = sec->output_section->vma + ent->new_offset;
+ /* The address calculation may overflow, giving us a
+ value greater than 4G on a 32-bit target when
+ dwarf_vma is 64-bit. */
+ if (sizeof (address) > 4 && ptr_size == 4)
+ address &= 0xffffffff;
+ hdr_info->u.dwarf.array[hdr_info->array_count].initial_loc
+ = address;
+ hdr_info->u.dwarf.array[hdr_info->array_count].range
+ = read_value (abfd, buf + width, width, FALSE);
+ hdr_info->u.dwarf.array[hdr_info->array_count++].fde
+ = (sec->output_section->vma
+ + sec->output_offset
+ + ent->new_offset);
}
- if ((ent->lsda_encoding & 0xf0) == DW_EH_PE_pcrel
- || ent->cie_inf->need_lsda_relative)
+ if ((ent->lsda_encoding & 0x70) == DW_EH_PE_pcrel
+ || cie->u.cie.make_lsda_relative)
{
buf += ent->lsda_offset;
width = get_DW_EH_PE_width (ent->lsda_encoding, ptr_size);
get_DW_EH_PE_signed (ent->lsda_encoding));
if (value)
{
- if ((ent->lsda_encoding & 0xf0) == DW_EH_PE_pcrel)
- value += ent->offset - ent->new_offset;
- else if (ent->cie_inf->need_lsda_relative)
- value -= (sec->output_section->vma + ent->new_offset + 8
- + ent->lsda_offset);
+ if ((ent->lsda_encoding & 0x70) == DW_EH_PE_pcrel)
+ value += (bfd_vma) ent->offset - ent->new_offset;
+ else if (cie->u.cie.make_lsda_relative)
+ value -= (sec->output_section->vma
+ + sec->output_offset
+ + ent->new_offset + 8 + ent->lsda_offset);
write_value (abfd, buf, value, width);
}
}
- else if (ent->cie_inf->add_augmentation_size)
+ else if (ent->add_augmentation_size)
{
/* Skip the PC and length and insert a zero byte for the
augmentation size. */
if (ent->set_loc)
{
/* Adjust DW_CFA_set_loc. */
- unsigned int cnt, width;
+ unsigned int cnt;
bfd_vma new_offset;
width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
for (cnt = 1; cnt <= ent->set_loc[0]; cnt++)
{
- bfd_vma value;
buf = start + ent->set_loc[cnt];
value = read_value (abfd, buf, width,
if (!value)
continue;
- if ((ent->fde_encoding & 0xf0) == DW_EH_PE_pcrel)
- value += ent->offset + 8 - new_offset;
- if (ent->cie_inf->make_relative)
- value -= sec->output_section->vma + new_offset
- + ent->set_loc[cnt];
+ if ((ent->fde_encoding & 0x70) == DW_EH_PE_pcrel)
+ value += (bfd_vma) ent->offset + 8 - new_offset;
+ if (ent->make_relative)
+ value -= (sec->output_section->vma
+ + sec->output_offset
+ + new_offset + ent->set_loc[cnt]);
write_value (abfd, buf, value, width);
}
}
}
}
- /* We don't align the section to its section alignment since the
- runtime library only expects all CIE/FDE records aligned at
- the pointer size. _bfd_elf_discard_section_eh_frame should
- have padded CIE/FDE records to multiple of pointer size with
- size_of_output_cie_fde. */
- if ((sec->size % ptr_size) != 0)
- abort ();
-
+ /* FIXME: octets_per_byte. */
return bfd_set_section_contents (abfd, sec->output_section,
contents, (file_ptr) sec->output_offset,
sec->size);
static int
vma_compare (const void *a, const void *b)
{
- const struct eh_frame_array_ent *p = a;
- const struct eh_frame_array_ent *q = b;
+ const struct eh_frame_array_ent *p = (const struct eh_frame_array_ent *) a;
+ const struct eh_frame_array_ent *q = (const struct eh_frame_array_ent *) b;
if (p->initial_loc > q->initial_loc)
return 1;
if (p->initial_loc < q->initial_loc)
return -1;
+ if (p->range > q->range)
+ return 1;
+ if (p->range < q->range)
+ return -1;
return 0;
}
-/* Write out .eh_frame_hdr section. This must be called after
- _bfd_elf_write_section_eh_frame has been called on all input
- .eh_frame sections.
- .eh_frame_hdr format:
+/* Reorder .eh_frame_entry sections to match the associated text sections.
+ This routine is called during the final linking step, just before writing
+ the contents. At this stage, sections in the eh_frame_hdr_info are already
+ sorted in order of increasing text section address and so we simply need
+ to make the .eh_frame_entrys follow that same order. Note that it is
+ invalid for a linker script to try to force a particular order of
+ .eh_frame_entry sections. */
+
+bfd_boolean
+_bfd_elf_fixup_eh_frame_hdr (struct bfd_link_info *info)
+{
+ asection *sec = NULL;
+ asection *osec;
+ struct eh_frame_hdr_info *hdr_info;
+ unsigned int i;
+ bfd_vma offset;
+ struct bfd_link_order *p;
+
+ hdr_info = &elf_hash_table (info)->eh_info;
+
+ if (hdr_info->hdr_sec == NULL
+ || info->eh_frame_hdr_type != COMPACT_EH_HDR
+ || hdr_info->array_count == 0)
+ return TRUE;
+
+ /* Change section output offsets to be in text section order. */
+ offset = 8;
+ osec = hdr_info->u.compact.entries[0]->output_section;
+ for (i = 0; i < hdr_info->array_count; i++)
+ {
+ sec = hdr_info->u.compact.entries[i];
+ if (sec->output_section != osec)
+ {
+ _bfd_error_handler
+ (_("invalid output section for .eh_frame_entry: %pA"),
+ sec->output_section);
+ return FALSE;
+ }
+ sec->output_offset = offset;
+ offset += sec->size;
+ }
+
+
+ /* Fix the link_order to match. */
+ for (p = sec->output_section->map_head.link_order; p != NULL; p = p->next)
+ {
+ if (p->type != bfd_indirect_link_order)
+ abort();
+
+ p->offset = p->u.indirect.section->output_offset;
+ if (p->next != NULL)
+ i--;
+ }
+
+ if (i != 0)
+ {
+ _bfd_error_handler
+ (_("invalid contents in %pA section"), osec);
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+/* The .eh_frame_hdr format for Compact EH frames:
+ ubyte version (2)
+ ubyte eh_ref_enc (DW_EH_PE_* encoding of typinfo references)
+ uint32_t count (Number of entries in table)
+ [array from .eh_frame_entry sections] */
+
+static bfd_boolean
+write_compact_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
+{
+ struct elf_link_hash_table *htab;
+ struct eh_frame_hdr_info *hdr_info;
+ asection *sec;
+ const struct elf_backend_data *bed;
+ bfd_vma count;
+ bfd_byte contents[8];
+ unsigned int i;
+
+ htab = elf_hash_table (info);
+ hdr_info = &htab->eh_info;
+ sec = hdr_info->hdr_sec;
+
+ if (sec->size != 8)
+ abort();
+
+ for (i = 0; i < sizeof (contents); i++)
+ contents[i] = 0;
+
+ contents[0] = COMPACT_EH_HDR;
+ bed = get_elf_backend_data (abfd);
+
+ BFD_ASSERT (bed->compact_eh_encoding);
+ contents[1] = (*bed->compact_eh_encoding) (info);
+
+ count = (sec->output_section->size - 8) / 8;
+ bfd_put_32 (abfd, count, contents + 4);
+ return bfd_set_section_contents (abfd, sec->output_section, contents,
+ (file_ptr) sec->output_offset, sec->size);
+}
+
+/* The .eh_frame_hdr format for DWARF frames:
+
ubyte version (currently 1)
- ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of
+ ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of
.eh_frame section)
ubyte fde_count_enc (DW_EH_PE_* encoding of total FDE count
number (or DW_EH_PE_omit if there is no
FDE initial_location field and FDE address,
sorted by increasing initial_loc). */
-bfd_boolean
-_bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
+static bfd_boolean
+write_dwarf_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
{
struct elf_link_hash_table *htab;
struct eh_frame_hdr_info *hdr_info;
asection *sec;
- bfd_byte *contents;
- asection *eh_frame_sec;
- bfd_size_type size;
- bfd_boolean retval;
- bfd_vma encoded_eh_frame;
+ bfd_boolean retval = TRUE;
htab = elf_hash_table (info);
hdr_info = &htab->eh_info;
sec = hdr_info->hdr_sec;
- if (sec == NULL)
- return TRUE;
+ bfd_byte *contents;
+ asection *eh_frame_sec;
+ bfd_size_type size;
+ bfd_vma encoded_eh_frame;
size = EH_FRAME_HDR_SIZE;
- if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count)
- size += 4 + hdr_info->fde_count * 8;
- contents = bfd_malloc (size);
+ if (hdr_info->u.dwarf.array
+ && hdr_info->array_count == hdr_info->u.dwarf.fde_count)
+ size += 4 + hdr_info->u.dwarf.fde_count * 8;
+ contents = (bfd_byte *) bfd_malloc (size);
if (contents == NULL)
return FALSE;
}
memset (contents, 0, EH_FRAME_HDR_SIZE);
- contents[0] = 1; /* Version. */
+ /* Version. */
+ contents[0] = 1;
+ /* .eh_frame offset. */
contents[1] = get_elf_backend_data (abfd)->elf_backend_encode_eh_address
- (abfd, info, eh_frame_sec, 0, sec, 4,
- &encoded_eh_frame); /* .eh_frame offset. */
+ (abfd, info, eh_frame_sec, 0, sec, 4, &encoded_eh_frame);
- if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count)
+ if (hdr_info->u.dwarf.array
+ && hdr_info->array_count == hdr_info->u.dwarf.fde_count)
{
- contents[2] = DW_EH_PE_udata4; /* FDE count encoding. */
- contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; /* Search table enc. */
+ /* FDE count encoding. */
+ contents[2] = DW_EH_PE_udata4;
+ /* Search table encoding. */
+ contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4;
}
else
{
if (contents[2] != DW_EH_PE_omit)
{
unsigned int i;
-
- bfd_put_32 (abfd, hdr_info->fde_count, contents + EH_FRAME_HDR_SIZE);
- qsort (hdr_info->array, hdr_info->fde_count, sizeof (*hdr_info->array),
- vma_compare);
- for (i = 0; i < hdr_info->fde_count; i++)
+ bfd_boolean overlap, overflow;
+
+ bfd_put_32 (abfd, hdr_info->u.dwarf.fde_count,
+ contents + EH_FRAME_HDR_SIZE);
+ qsort (hdr_info->u.dwarf.array, hdr_info->u.dwarf.fde_count,
+ sizeof (*hdr_info->u.dwarf.array), vma_compare);
+ overlap = FALSE;
+ overflow = FALSE;
+ for (i = 0; i < hdr_info->u.dwarf.fde_count; i++)
+ {
+ bfd_vma val;
+
+ val = hdr_info->u.dwarf.array[i].initial_loc
+ - sec->output_section->vma;
+ val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000;
+ if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64
+ && (hdr_info->u.dwarf.array[i].initial_loc
+ != sec->output_section->vma + val))
+ overflow = TRUE;
+ bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 4);
+ val = hdr_info->u.dwarf.array[i].fde - sec->output_section->vma;
+ val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000;
+ if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64
+ && (hdr_info->u.dwarf.array[i].fde
+ != sec->output_section->vma + val))
+ overflow = TRUE;
+ bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 8);
+ if (i != 0
+ && (hdr_info->u.dwarf.array[i].initial_loc
+ < (hdr_info->u.dwarf.array[i - 1].initial_loc
+ + hdr_info->u.dwarf.array[i - 1].range)))
+ overlap = TRUE;
+ }
+ if (overflow)
+ _bfd_error_handler (_(".eh_frame_hdr entry overflow"));
+ if (overlap)
+ _bfd_error_handler (_(".eh_frame_hdr refers to overlapping FDEs"));
+ if (overflow || overlap)
{
- bfd_put_32 (abfd,
- hdr_info->array[i].initial_loc
- - sec->output_section->vma,
- contents + EH_FRAME_HDR_SIZE + i * 8 + 4);
- bfd_put_32 (abfd,
- hdr_info->array[i].fde - sec->output_section->vma,
- contents + EH_FRAME_HDR_SIZE + i * 8 + 8);
+ bfd_set_error (bfd_error_bad_value);
+ retval = FALSE;
}
}
- retval = bfd_set_section_contents (abfd, sec->output_section,
- contents, (file_ptr) sec->output_offset,
- sec->size);
+ /* FIXME: octets_per_byte. */
+ if (!bfd_set_section_contents (abfd, sec->output_section, contents,
+ (file_ptr) sec->output_offset,
+ sec->size))
+ retval = FALSE;
free (contents);
+
+ free (hdr_info->u.dwarf.array);
return retval;
}
+/* Write out .eh_frame_hdr section. This must be called after
+ _bfd_elf_write_section_eh_frame has been called on all input
+ .eh_frame sections. */
+
+bfd_boolean
+_bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
+{
+ struct elf_link_hash_table *htab;
+ struct eh_frame_hdr_info *hdr_info;
+ asection *sec;
+
+ htab = elf_hash_table (info);
+ hdr_info = &htab->eh_info;
+ sec = hdr_info->hdr_sec;
+
+ if (info->eh_frame_hdr_type == 0 || sec == NULL)
+ return TRUE;
+
+ if (info->eh_frame_hdr_type == COMPACT_EH_HDR)
+ return write_compact_eh_frame_hdr (abfd, info);
+ else
+ return write_dwarf_eh_frame_hdr (abfd, info);
+}
+
/* Return the width of FDE addresses. This is the default implementation. */
unsigned int
-_bfd_elf_eh_frame_address_size (bfd *abfd, asection *sec ATTRIBUTE_UNUSED)
+_bfd_elf_eh_frame_address_size (bfd *abfd, const asection *sec ATTRIBUTE_UNUSED)
{
return elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 ? 8 : 4;
}
projects / deliverable / binutils-gdb.git / blobdiff