/* .eh_frame section optimization.
- Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007
+ Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
Free Software Foundation, Inc.
Written by Jakub Jelinek <jakub@redhat.com>.
#include "bfd.h"
#include "libbfd.h"
#include "elf-bfd.h"
-#include "elf/dwarf2.h"
+#include "dwarf2.h"
#define EH_FRAME_HDR_SIZE 8
union {
struct elf_link_hash_entry *h;
bfd_vma val;
+ unsigned int reloc_index;
} personality;
asection *output_sec;
struct eh_cie_fde *cie_inf;
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
static hashval_t
cie_hash (const void *e)
{
- const struct cie *c = e;
+ const struct cie *c = (const struct cie *) e;
return c->hash;
}
{
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 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. */
+/* Called before calling _bfd_elf_parse_eh_frame on every input bfd's
+ .eh_frame section. */
-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)
+void
+_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;
+ hdr_info->merge_cies = !info->relocatable;
+}
+
+/* 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;
+
+ htab = elf_hash_table (info);
+ hdr_info = &htab->eh_info;
+ if (hdr_info->parsed_eh_frames)
+ return;
if (sec->size == 0)
{
/* 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));
{
/* Empty .eh_frame section. */
free (ehbuf);
- return FALSE;
+ return;
}
/* If .eh_frame section size doesn't fit into int, we cannot handle
->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. */
+ 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))
+ /* 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)
{
/* 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;
+ cie->output_sec = sec->output_section;
start = buf;
REQUIRE (read_byte (&buf, end, &cie->version));
}
ENSURE_NO_RELOCS (buf);
/* Ensure we have a reloc here. */
- 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
- || 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:
(abfd, info, sec)))
{
if ((cie->fde_encoding & 0xf0) == DW_EH_PE_absptr)
- cie->make_relative = 1;
+ 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. */
{
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;
}
}
->elf_backend_can_make_lsda_relative_eh_frame
(abfd, info, sec))
&& (cie->lsda_encoding & 0xf0) == DW_EH_PE_absptr)
- cie->make_lsda_relative = 1;
+ cie->can_make_lsda_relative = 1;
/* If FDE encoding was not specified, it defaults to
DW_EH_absptr. */
insns = buf;
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;
}
else
{
+ asection *rsec;
+
/* 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
+ /* Chain together the FDEs for each section. */
+ rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie);
+ /* RSEC will be NULL if FDE was cleared out as it was belonging to
+ a discarded SHT_GROUP. */
+ if (rsec)
{
- if (info->shared
- && (((cie->fde_encoding & 0xf0) == DW_EH_PE_absptr
- && cie->make_relative == 0)
- || (cie->fde_encoding & 0xf0) == DW_EH_PE_aligned))
- {
- /* 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);
- }
- ecie->usage_count++;
- hdr_info->fde_count++;
- this_inf->cie_inf = (void *) (ecie - ecies);
+ REQUIRE (rsec->owner == abfd);
+ this_inf->u.fde.next_for_section = elf_fde_list (rsec);
+ elf_fde_list (rsec) = this_inf;
}
/* Skip the initial location and address range. */
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);
}
}
if (set_loc_count
&& ((cie->fde_encoding & 0xf0) == DW_EH_PE_pcrel
- || cie->make_relative))
+ || this_inf->make_relative))
{
unsigned int cnt;
bfd_byte *p;
- this_inf->set_loc = bfd_malloc ((set_loc_count + 1)
- * sizeof (unsigned int));
+ 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;
}
}
+ 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 = ELF_INFO_TYPE_EH_FRAME;
+ if (hdr_info->merge_cies)
+ {
+ sec_info->cies = local_cies;
+ local_cies = NULL;
+ }
+ goto success;
+
+ free_no_table:
+ (*info->callbacks->einfo)
+ (_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"),
+ abfd, sec);
+ hdr_info->table = FALSE;
+ if (sec_info)
+ free (sec_info);
+ success:
+ if (ehbuf)
+ free (ehbuf);
+ if (local_cies)
+ free (local_cies);
+#undef REQUIRE
+}
+
+/* Finish a pass over all .eh_frame sections. */
+
+void
+_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;
+ hdr_info->parsed_eh_frames = 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;
- /* 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)
+ 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 (ecie->usage_count == 0)
+ 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->u.cie.gc_mark)
{
- sec_info->entry[ecie->entry].removed = 1;
- continue;
+ cie->u.cie.gc_mark = 1;
+ if (!mark_entry (info, eh_frame, cie, gc_mark_hook, cookie))
+ return FALSE;
}
- 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)
+ }
+ 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)
{
- 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;
- }
+ struct elf_link_hash_entry *h;
- *loc = malloc (sizeof (struct cie));
- if (*loc == NULL)
- *loc = HTAB_DELETED_ENTRY;
- else
- memcpy (*loc, &ecie->cie, sizeof (struct cie));
- }
+ 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);
}
- 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;
}
- /* Ok, now we can assign new offsets. */
- offset = 0;
+ /* 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 = (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;
+}
+
+/* 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. */
+
+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;
+
+ sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info;
+ if (sec_info == NULL)
+ return FALSE;
+
+ hdr_info = &elf_hash_table (info)->eh_info;
for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent)
- if (!ent->removed)
+ 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)
{
- if (!ent->cie)
+ cookie->rel = cookie->rels + ent->reloc_index;
+ /* FIXME: octets_per_byte. */
+ BFD_ASSERT (cookie->rel < cookie->relend
+ && cookie->rel->r_offset == ent->offset + 8);
+ if (!(*reloc_symbol_deleted_p) (ent->offset + 8, cookie))
{
- ecie = ecies + (bfd_hostptr_t) ent->cie_inf;
- ent->cie_inf = ecie->cie.cie_inf;
+ if (info->shared
+ && (((ent->fde_encoding & 0xf0) == DW_EH_PE_absptr
+ && ent->make_relative == 0)
+ || (ent->fde_encoding & 0xf0) == DW_EH_PE_aligned))
+ {
+ /* 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);
+ }
+ ent->removed = 0;
+ hdr_info->fde_count++;
+ 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;
+ for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent)
+ if (!ent->removed)
+ {
ent->new_offset = offset;
offset += size_of_output_cie_fde (ent, ptr_size);
}
- /* Resize the sec as needed. */
sec->rawsize = sec->size;
sec->size = offset;
-
- 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
}
/* This function is called for .eh_frame_hdr section after
if (sec->sec_info_type != ELF_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;
/* 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
struct eh_cie_fde *ent;
if (sec->sec_info_type != ELF_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)
- {
- 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;
- }
-
if (hdr_info->table && hdr_info->array == NULL)
- hdr_info->array
- = bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array));
+ hdr_info->array = (struct eh_frame_array_ent *)
+ bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array));
if (hdr_info->array == NULL)
hdr_info = NULL;
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)
{
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);
{
/* 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;
/* 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);
*aug++ = 'z';
*buf++ = extra_data - 1;
}
- if (ent->add_fde_encoding)
+ if (ent->u.cie.add_fde_encoding)
{
BFD_ASSERT (action & 1);
*aug++ = 'R';
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);
+ == ent->u.cie.per_encoding_relative);
if ((per_encoding & 0xf0) == DW_EH_PE_aligned)
buf = (contents
+ ((buf - contents + per_width - 1)
val = read_value (abfd, buf, per_width,
get_DW_EH_PE_signed (per_encoding));
- val += ent->offset - ent->new_offset;
+ val += (bfd_vma) ent->offset - ent->new_offset;
val -= extra_string + extra_data;
write_value (abfd, buf, val, per_width);
action &= ~4;
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);
buf += 4;
width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
}
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);
}
{
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;
+ = (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)
+ || cie->u.cie.make_lsda_relative)
{
buf += ent->lsda_offset;
width = get_DW_EH_PE_width (ent->lsda_encoding, ptr_size);
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);
+ 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. */
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];
+ 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);
}
}
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)
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);
+ contents = (bfd_byte *) bfd_malloc (size);
if (contents == NULL)
return FALSE;
}
}
+ /* FIXME: octets_per_byte. */
retval = bfd_set_section_contents (abfd, sec->output_section,
contents, (file_ptr) sec->output_offset,
sec->size);
projects / msp430-binutils.git / blobdiff