/* .eh_frame section optimization.
- Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
- Free Software Foundation, Inc.
+ Copyright (C) 2001-2014 Free Software Foundation, Inc.
Written by Jakub Jelinek <jakub@redhat.com>.
This file is part of BFD, the Binary File Descriptor library.
bfd_vma augmentation_size;
union {
struct elf_link_hash_entry *h;
- bfd_vma val;
+ struct {
+ unsigned int bfd_id;
+ unsigned int index;
+ } sym;
unsigned int reloc_index;
} personality;
- asection *output_sec;
struct eh_cie_fde *cie_inf;
unsigned char per_encoding;
unsigned char lsda_encoding;
&& c1->augmentation_size == c2->augmentation_size
&& memcmp (&c1->personality, &c2->personality,
sizeof (c1->personality)) == 0
- && c1->output_sec == c2->output_sec
+ && (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)
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;
}
return encoding | DW_EH_PE_pcrel;
}
-/* Called before calling _bfd_elf_parse_eh_frame on every input bfd's
- .eh_frame section. */
-
-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. */
htab = elf_hash_table (info);
hdr_info = &htab->eh_info;
- if (hdr_info->parsed_eh_frames)
- return;
if (sec->size == 0
- || sec->sec_info_type != ELF_INFO_TYPE_NONE)
+ || sec->sec_info_type != SEC_INFO_TYPE_NONE)
{
/* This file does not contain .eh_frame information. */
return;
/* 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) \
cie->cie_inf = this_inf;
cie->length = hdr_length;
- cie->output_sec = sec->output_section;
start = buf;
REQUIRE (read_byte (&buf, end, &cie->version));
/* For shared libraries, try to get rid of as many RELATIVE relocs
as possible. */
if (info->shared
+ && !info->relocatable
&& (get_elf_backend_data (abfd)
->elf_backend_can_make_relative_eh_frame
(abfd, info, sec)))
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 (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;
+ if (!info->relocatable)
+ {
+ /* 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
{
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)
+ (_("discarding zero address range FDE in %B(%A).\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));
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->sec_info_type = SEC_INFO_TYPE_EH_FRAME;
+ if (!info->relocatable)
{
+ /* Keep info for merging cies. */
sec_info->cies = local_cies;
local_cies = NULL;
}
#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. */
/* 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)
+ 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))
{
bfd_boolean per_binds_local;
- /* Work out the address of personality routine, either as an absolute
- value or as a symbol. */
+ /* 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
return cie_inf;
cie->local_personality = 1;
- cie->personality.val = (sym->st_value
- + sym_sec->output_offset
- + sym_sec->output_section->vma);
+ cie->personality.sym.bfd_id = abfd->id;
+ cie->personality.sym.index = r_symndx;
per_binds_local = TRUE;
}
if (per_binds_local
&& info->shared
+ && !info->relocatable
&& (cie->per_encoding & 0x70) == DW_EH_PE_absptr
&& (get_elf_backend_data (abfd)
->elf_backend_can_make_relative_eh_frame (abfd, info, sec)))
}
/* 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)
{
struct eh_frame_hdr_info *hdr_info;
unsigned int ptr_size, offset;
- if (sec->sec_info_type != ELF_INFO_TYPE_EH_FRAME)
+ if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME)
return FALSE;
sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info;
/* 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)
+ else if (!ent->cie && ent->u.fde.cie_inf != NULL)
{
bfd_boolean keep;
if ((sec->flags & SEC_LINKER_CREATED) != 0 && cookie->rels == NULL)
since it is affected by runtime relocations. */
hdr_info->table = FALSE;
(*info->callbacks->einfo)
- (_("%P: fde encoding in %B(%A) prevents .eh_frame_hdr"
+ (_("%P: FDE encoding in %B(%A) prevents .eh_frame_hdr"
" table being created.\n"), abfd, sec);
}
ent->removed = 0;
if (hdr_info->table)
sec->size += 4 + hdr_info->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;
+}
+
/* 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;
if (hdr_info->hdr_sec == NULL)
return TRUE;
- if (bfd_is_abs_section (hdr_info->hdr_sec->output_section))
- {
- 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;
- }
-
- if (abfd == NULL)
+ if (bfd_is_abs_section (hdr_info->hdr_sec->output_section)
+ || !info->eh_frame_hdr
+ || !_bfd_elf_eh_frame_present (info))
{
hdr_info->hdr_sec->flags |= SEC_EXCLUDE;
hdr_info->hdr_sec = NULL;
struct eh_frame_sec_info *sec_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 = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info;
struct eh_frame_hdr_info *hdr_info;
unsigned int ptr_size;
struct eh_cie_fde *ent;
+ bfd_size_type sec_size;
- 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);
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 (info->relocatable)
+ continue;
buf += 4;
width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
value = read_value (abfd, buf, width,
if (sizeof (address) > 4 && ptr_size == 4)
address &= 0xffffffff;
hdr_info->array[hdr_info->array_count].initial_loc = address;
+ hdr_info->array[hdr_info->array_count].range
+ = read_value (abfd, buf + width, width, FALSE);
hdr_info->array[hdr_info->array_count++].fde
= (sec->output_section->vma
+ sec->output_offset
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)
+ sec_size = sec->size;
+ if (sec_info->count != 0
+ && sec_info->entry[sec_info->count - 1].size == 4)
+ sec_size -= 4;
+ if ((sec_size % ptr_size) != 0)
abort ();
/* FIXME: octets_per_byte. */
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;
}
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;
-
- 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_byte *) bfd_malloc (size);
- if (contents == NULL)
- return FALSE;
- eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame");
- if (eh_frame_sec == NULL)
+ if (info->eh_frame_hdr && sec != NULL)
{
- free (contents);
- return FALSE;
- }
+ 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_byte *) bfd_malloc (size);
+ if (contents == NULL)
+ return FALSE;
- memset (contents, 0, EH_FRAME_HDR_SIZE);
- contents[0] = 1; /* Version. */
- 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. */
+ eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame");
+ if (eh_frame_sec == NULL)
+ {
+ free (contents);
+ return FALSE;
+ }
- if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count)
- {
- contents[2] = DW_EH_PE_udata4; /* FDE count encoding. */
- contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; /* Search table enc. */
- }
- else
- {
- contents[2] = DW_EH_PE_omit;
- contents[3] = DW_EH_PE_omit;
- }
- bfd_put_32 (abfd, encoded_eh_frame, contents + 4);
+ memset (contents, 0, EH_FRAME_HDR_SIZE);
+ /* 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);
- if (contents[2] != DW_EH_PE_omit)
- {
- unsigned int i;
+ if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count)
+ {
+ /* FDE count encoding. */
+ contents[2] = DW_EH_PE_udata4;
+ /* Search table encoding. */
+ contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4;
+ }
+ else
+ {
+ contents[2] = DW_EH_PE_omit;
+ contents[3] = DW_EH_PE_omit;
+ }
+ bfd_put_32 (abfd, encoded_eh_frame, contents + 4);
- 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++)
+ if (contents[2] != DW_EH_PE_omit)
{
- 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);
+ 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_vma val;
+
+ val = hdr_info->array[i].initial_loc - sec->output_section->vma;
+ val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000;
+ if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64
+ && (hdr_info->array[i].initial_loc
+ != sec->output_section->vma + val))
+ (*info->callbacks->einfo)
+ (_("%X%P: .eh_frame_hdr table[%u] PC overflow.\n"), i);
+ bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 4);
+
+ val = hdr_info->array[i].fde - sec->output_section->vma;
+ val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000;
+ if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64
+ && (hdr_info->array[i].fde
+ != sec->output_section->vma + val))
+ (*info->callbacks->einfo)
+ (_("%X%P: .eh_frame_hdr table[%u] FDE overflow.\n"), i);
+ bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 8);
+
+ if (i != 0
+ && (hdr_info->array[i].initial_loc
+ < (hdr_info->array[i - 1].initial_loc
+ + hdr_info->array[i - 1].range)))
+ (*info->callbacks->einfo)
+ (_("%X%P: .eh_frame_hdr table[%u] FDE at %V overlaps "
+ "table[%u] FDE at %V.\n"),
+ i - 1, hdr_info->array[i - 1].fde,
+ i, hdr_info->array[i].fde);
+ }
}
- }
- /* FIXME: octets_per_byte. */
- retval = bfd_set_section_contents (abfd, sec->output_section,
- contents, (file_ptr) sec->output_offset,
- sec->size);
- free (contents);
+ /* 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);
+ }
+ if (hdr_info->array != NULL)
+ free (hdr_info->array);
return retval;
}