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authorRichard Sandiford <rdsandiford@googlemail.com>2008-01-09 09:36:11 +0000
committerRichard Sandiford <rdsandiford@googlemail.com>2008-01-09 09:36:11 +0000
commit184d07da89afd7b64fedf2360e9412f3f221b5f8 (patch)
tree86d884295ea4540e85611148f03072cca17887ae /bfd/elf-eh-frame.c
parent137033e97482d340139b1499c6db4236f35c8577 (diff)
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PR ld/5526 * elf-bfd.h (eh_cie_fde): Add u.cie.u.full_cie and u.cie.merged fields. Rename u.cie.u.merged to u.cie.u.merged_with. (eh_frame_sec_info): Add a cies field. (eh_frame_hdr_info): Add a merge_cies field. * elf-eh-frame.c (cie): Add a reloc_index member to the personality union. (_bfd_elf_begin_eh_frame_parsing): Set hdr_info->merge_cies instead of hdr_info->cies. (_bfd_elf_parse_eh_frame): Remove tmp_cie. Ccreate an array of cie structures in all cases and use it instead of extended_cies. If merging, store the cie array in sec_info->cies and point each CIE's eh_fde_cie at the associated element. Do not try to calculate the value of the personality routine here; record the offset of the relocation instead. Do not merge CIEs here. (_bfd_elf_end_eh_frame_parsing): Do not free hdr_info->cies here... (_bfd_elf_discard_section_eh_frame_hdr): ...do it here instead. (_bfd_elf_gc_mark_fdes): Mark the original (unmerged) CIE. (find_merged_cie): New function. (_bfd_elf_gc_mark_fdes): Use it. Free sec_info->cies. ld/testsuite/ PR ld/5526 * ld-elf/eh6.s, ld-elf/eh6.d: New test.
Diffstat (limited to 'bfd/elf-eh-frame.c')
-rw-r--r--bfd/elf-eh-frame.c323
1 files changed, 170 insertions, 153 deletions
diff --git a/bfd/elf-eh-frame.c b/bfd/elf-eh-frame.c
index f8386d3..087c6b0 100644
--- a/bfd/elf-eh-frame.c
+++ b/bfd/elf-eh-frame.c
@@ -42,6 +42,7 @@ struct cie
union {
struct elf_link_hash_entry *h;
bfd_vma val;
+ unsigned int reloc_index;
} personality;
asection *output_sec;
struct eh_cie_fde *cie_inf;
@@ -431,8 +432,7 @@ _bfd_elf_begin_eh_frame_parsing (struct bfd_link_info *info)
struct eh_frame_hdr_info *hdr_info;
hdr_info = &elf_hash_table (info)->eh_info;
- if (!hdr_info->parsed_eh_frames && !info->relocatable)
- hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free);
+ hdr_info->merge_cies = !info->relocatable;
}
/* Try to parse .eh_frame section SEC, which belongs to ABFD. Store the
@@ -453,13 +453,8 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
bfd_byte *last_fde;
struct eh_cie_fde *this_inf;
unsigned int hdr_length, hdr_id;
- struct extended_cie
- {
- struct cie *cie;
- struct eh_cie_fde *local_cie;
- } *ecies = NULL, *ecie;
- unsigned int ecie_count;
- struct cie *cie, *local_cies = NULL, tmp_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;
@@ -538,16 +533,9 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
+ (num_entries - 1) * sizeof (struct eh_cie_fde));
REQUIRE (sec_info);
- ecies = bfd_zmalloc (num_cies * sizeof (*ecies));
- REQUIRE (ecies);
-
- /* If we're not merging CIE entries (such as for a relocatable link),
- we need to have a "struct cie" for each CIE in this section. */
- if (hdr_info->cies == NULL)
- {
- local_cies = bfd_zmalloc (num_cies * sizeof (*local_cies));
- REQUIRE (local_cies);
- }
+ /* We need to have a "struct cie" for each CIE in this section. */
+ local_cies = bfd_zmalloc (num_cies * sizeof (*local_cies));
+ REQUIRE (local_cies);
#define ENSURE_NO_RELOCS(buf) \
REQUIRE (!(cookie->rel < cookie->relend \
@@ -568,7 +556,7 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
? cookie->rel : NULL)
buf = ehbuf;
- ecie_count = 0;
+ cie_count = 0;
gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
while ((bfd_size_type) (buf - ehbuf) != sec->size)
{
@@ -612,16 +600,9 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
/* CIE */
this_inf->cie = 1;
- /* If we're merging CIEs, construct the struct cie in TMP_CIE;
- we'll enter it into the global pool later. Otherwise point
- CIE to one of the section-local cie structures. */
- if (local_cies)
- cie = local_cies + ecie_count;
- else
- {
- cie = &tmp_cie;
- memset (cie, 0, sizeof (*cie));
- }
+ /* Point CIE to one of the section-local cie structures. */
+ cie = local_cies + cie_count++;
+
cie->cie_inf = this_inf;
cie->length = hdr_length;
cie->output_sec = sec->output_section;
@@ -697,64 +678,14 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
}
ENSURE_NO_RELOCS (buf);
/* Ensure we have a reloc here. */
- if (GET_RELOC (buf) != NULL)
- {
- unsigned long r_symndx;
-
-#ifdef BFD64
- if (elf_elfheader (abfd)->e_ident[EI_CLASS]
- == ELFCLASS64)
- 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
- || 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;
- }
- else
- {
- Elf_Internal_Sym *sym;
- asection *sym_sec;
- bfd_vma val;
-
- sym = &cookie->locsyms[r_symndx];
- sym_sec = (bfd_section_from_elf_index
- (abfd, sym->st_shndx));
- if (sym_sec != NULL)
- {
- if (sym_sec->kept_section != NULL)
- sym_sec = sym_sec->kept_section;
- if (sym_sec->output_section != NULL)
- {
- val = (sym->st_value
- + sym_sec->output_offset
- + sym_sec->output_section->vma);
- cie->personality.val = val;
- cie->local_personality = 1;
- }
- }
- }
-
- /* Cope with MIPS-style composite relocations. */
- do
- cookie->rel++;
- while (GET_RELOC (buf) != NULL);
- }
+ 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->local_personality || cie->personality.h);
}
break;
default:
@@ -807,6 +738,8 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
buf += initial_insn_length;
ENSURE_NO_RELOCS (buf);
+ if (hdr_info->merge_cies)
+ this_inf->u.cie.u.full_cie = cie;
this_inf->u.cie.per_encoding_relative
= (cie->per_encoding & 0x70) == DW_EH_PE_pcrel;
}
@@ -816,18 +749,17 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
/* 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->local_cie->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;
- this_inf->u.fde.cie_inf = ecie->local_cie;
- this_inf->make_relative = ecie->local_cie->make_relative;
+ 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
- = ecie->local_cie->add_augmentation_size;
+ = cie->cie_inf->add_augmentation_size;
ENSURE_NO_RELOCS (buf);
REQUIRE (GET_RELOC (buf));
@@ -915,37 +847,18 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
this_inf->removed = 1;
this_inf->fde_encoding = cie->fde_encoding;
this_inf->lsda_encoding = cie->lsda_encoding;
- if (this_inf->cie)
- {
- /* We have now finished constructing the struct cie. */
- if (hdr_info->cies != NULL)
- {
- /* See if we can merge this CIE with an earlier one. */
- void **loc;
-
- cie_compute_hash (cie);
- loc = htab_find_slot_with_hash (hdr_info->cies, cie,
- cie->hash, INSERT);
- REQUIRE (loc);
- if (*loc == HTAB_EMPTY_ENTRY)
- {
- *loc = malloc (sizeof (struct cie));
- REQUIRE (*loc);
- memcpy (*loc, cie, sizeof (struct cie));
- }
- cie = (struct cie *) *loc;
- }
- this_inf->u.cie.u.merged = cie->cie_inf;
- ecies[ecie_count].cie = cie;
- ecies[ecie_count++].local_cie = this_inf;
- }
sec_info->count++;
}
BFD_ASSERT (sec_info->count == num_entries);
- BFD_ASSERT (ecie_count == num_cies);
+ BFD_ASSERT (cie_count == num_cies);
elf_section_data (sec)->sec_info = sec_info;
sec->sec_info_type = ELF_INFO_TYPE_EH_FRAME;
+ if (hdr_info->merge_cies)
+ {
+ sec_info->cies = local_cies;
+ local_cies = NULL;
+ }
goto success;
free_no_table:
@@ -958,8 +871,6 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
success:
if (ehbuf)
free (ehbuf);
- if (ecies)
- free (ecies);
if (local_cies)
free (local_cies);
#undef REQUIRE
@@ -973,11 +884,6 @@ _bfd_elf_end_eh_frame_parsing (struct bfd_link_info *info)
struct eh_frame_hdr_info *hdr_info;
hdr_info = &elf_hash_table (info)->eh_info;
- if (hdr_info->cies != NULL)
- {
- htab_delete (hdr_info->cies);
- hdr_info->cies = NULL;
- }
hdr_info->parsed_eh_frames = TRUE;
}
@@ -1009,7 +915,7 @@ _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, *merged;
+ struct eh_cie_fde *fde, *cie;
for (fde = elf_fde_list (sec); fde; fde = fde->u.fde.next_for_section)
{
@@ -1019,10 +925,9 @@ _bfd_elf_gc_mark_fdes (struct bfd_link_info *info, asection *sec,
/* 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;
- merged = cie->u.cie.u.merged;
- if (!merged->u.cie.gc_mark)
+ if (!cie->u.cie.gc_mark)
{
- merged->u.cie.gc_mark = 1;
+ cie->u.cie.gc_mark = 1;
if (!mark_entry (info, eh_frame, cie, gc_mark_hook, cookie))
return FALSE;
}
@@ -1030,6 +935,126 @@ _bfd_elf_gc_mark_fdes (struct bfd_link_info *info, asection *sec,
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, 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)
+ {
+ /* Work out the address of personality routine, either as an absolute
+ value or as a symbol. */
+ 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;
+ }
+ 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.val = (sym->st_value
+ + sym_sec->output_offset
+ + sym_sec->output_section->vma);
+ }
+ }
+
+ /* See if we can merge this CIE with an earlier one. */
+ cie->output_sec = sec->output_section;
+ cie_compute_hash (cie);
+ if (hdr_info->cies == NULL)
+ {
+ hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free);
+ if (hdr_info->cies == NULL)
+ return cie_inf;
+ }
+ loc = htab_find_slot_with_hash (hdr_info->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 = 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;
+}
+
/* 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
@@ -1041,7 +1066,7 @@ _bfd_elf_discard_section_eh_frame
bfd_boolean (*reloc_symbol_deleted_p) (bfd_vma, void *),
struct elf_reloc_cookie *cookie)
{
- struct eh_cie_fde *ent, *cie, *merged;
+ struct eh_cie_fde *ent;
struct eh_frame_sec_info *sec_info;
struct eh_frame_hdr_info *hdr_info;
unsigned int ptr_size, offset;
@@ -1075,31 +1100,17 @@ _bfd_elf_discard_section_eh_frame
}
ent->removed = 0;
hdr_info->fde_count++;
-
- cie = ent->u.fde.cie_inf;
- if (cie->removed)
- {
- merged = cie->u.cie.u.merged;
- if (!merged->removed)
- /* We have decided to keep the group representative. */
- ent->u.fde.cie_inf = merged;
- else if (merged->u.cie.u.merged != merged)
- /* We didn't keep the original group representative,
- but we did keep an alternative. */
- ent->u.fde.cie_inf = merged->u.cie.u.merged;
- else
- {
- /* Make the local CIE represent the merged group. */
- merged->u.cie.u.merged = cie;
- cie->removed = 0;
- cie->u.cie.u.sec = sec;
- cie->u.cie.make_lsda_relative
- = merged->u.cie.make_lsda_relative;
- }
- }
+ ent->u.fde.cie_inf = find_merged_cie (abfd, sec, hdr_info, cookie,
+ ent->u.fde.cie_inf);
}
}
+ if (sec_info->cies)
+ {
+ free (sec_info->cies);
+ sec_info->cies = NULL;
+ }
+
ptr_size = (get_elf_backend_data (sec->owner)
->elf_backend_eh_frame_address_size (sec->owner, sec));
offset = 0;
@@ -1129,6 +1140,12 @@ _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
htab = elf_hash_table (info);
hdr_info = &htab->eh_info;
+ if (hdr_info->cies != NULL)
+ {
+ htab_delete (hdr_info->cies);
+ hdr_info->cies = NULL;
+ }
+
sec = hdr_info->hdr_sec;
if (sec == NULL)
return FALSE;