/* .eh_frame section optimization.
- Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011,
- 2012 Free Software Foundation, Inc.
+ Copyright (C) 2001-2016 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. */
+/* Examine each .eh_frame_entry section and discard those
+ those that are marked SEC_EXCLUDE. */
-void
-_bfd_elf_begin_eh_frame_parsing (struct bfd_link_info *info)
+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_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;
- hdr_info = &elf_hash_table (info)->eh_info;
- hdr_info->merge_cies = !info->relocatable;
+ 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
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 != SEC_INFO_TYPE_NONE)
/* 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
+ if (bfd_link_pic (info)
&& (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 (!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
{
REQUIRE (GET_RELOC (buf));
/* Chain together the FDEs for each section. */
- rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie);
+ 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)
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));
elf_section_data (sec)->sec_info = sec_info;
sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME;
- if (hdr_info->merge_cies)
+ if (!bfd_link_relocatable (info))
{
+ /* Keep info for merging cies. */
sec_info->cies = local_cies;
local_cies = NULL;
}
(*info->callbacks->einfo)
(_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"),
abfd, sec);
- hdr_info->table = FALSE;
+ hdr_info->u.dwarf.table = FALSE;
if (sec_info)
free (sec_info);
success:
#undef REQUIRE
}
-/* Finish a pass over all .eh_frame sections. */
+/* Order eh_frame_hdr entries by the VMA of their text section. */
-void
+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->owner, 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;
- hdr_info->parsed_eh_frames = TRUE;
+
+ 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
/* 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
+ && 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)))
}
/* 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)
+ if (hdr_info->u.dwarf.cies == NULL)
{
- hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free);
- if (hdr_info->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->cies, cie, cie->hash, INSERT);
+ loc = htab_find_slot_with_hash (hdr_info->u.dwarf.cies, cie,
+ cie->hash, INSERT);
if (loc == NULL)
return cie_inf;
/* 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)
}
if (keep)
{
- if (info->shared
+ 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->table = FALSE;
- (*info->callbacks->einfo)
- (_("%P: fde encoding in %B(%A) prevents .eh_frame_hdr"
- " table being created.\n"), abfd, sec);
+ hdr_info->u.dwarf.table = FALSE;
+ if (num_warnings_issued < 10)
+ {
+ (*info->callbacks->einfo)
+ (_("%P: FDE encoding in %B(%A) prevents .eh_frame_hdr"
+ " table being created.\n"), abfd, sec);
+ num_warnings_issued ++;
+ }
+ else if (num_warnings_issued == 10)
+ {
+ (*info->callbacks->einfo)
+ (_("%P: Further warnings about FDE encoding preventing .eh_frame_hdr generation dropped.\n"));
+ num_warnings_issued ++;
+ }
}
ent->removed = 0;
- hdr_info->fde_count++;
+ 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);
}
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)
{
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_get_section_name (abfd, 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
{
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;
return TRUE;
if (bfd_is_abs_section (hdr_info->hdr_sec->output_section)
- || !info->eh_frame_hdr
- || !_bfd_elf_eh_frame_present (info))
+ || 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;
}
- hdr_info->table = TRUE;
+ /* 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;
+
+ 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);
+
+ if (!hdr_info->frame_hdr_is_compact)
+ hdr_info->u.dwarf.table = TRUE;
return TRUE;
}
+ 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)
+ {
+ (*_bfd_error_handler) (_("%B: %s not in order"), sec->owner, sec->name);
+ 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)
+ {
+ (*_bfd_error_handler) (_("%B: %s invalid input section size"),
+ sec->owner, sec->name);
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+ }
+ if (last_addr >= addr + sec->rawsize)
+ {
+ (*_bfd_error_handler) (_("%B: %s points past end of text section"),
+ sec->owner, sec->name);
+ 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 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 != SEC_INFO_TYPE_EH_FRAME)
/* FIXME: octets_per_byte. */
htab = elf_hash_table (info);
hdr_info = &htab->eh_info;
- if (hdr_info->table && hdr_info->array == NULL)
- hdr_info->array = (struct eh_frame_array_ent *)
- bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array));
- if (hdr_info->array == NULL)
+ if (hdr_info->u.dwarf.table && hdr_info->u.dwarf.array == NULL)
+ {
+ 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->u.dwarf.array == NULL)
hdr_info = NULL;
/* The new offsets can be bigger or smaller than the original offsets.
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,
dwarf_vma is 64-bit. */
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++].fde
+ 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);
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;
}
-/* 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: %s"),
+ sec->output_section->name);
+ 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 %s section"), osec->name);
+ 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
.eh_frame section)
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;
htab = elf_hash_table (info);
hdr_info = &htab->eh_info;
sec = hdr_info->hdr_sec;
+ bfd_byte *contents;
+ asection *eh_frame_sec;
+ bfd_size_type size;
+ bfd_vma encoded_eh_frame;
+
+ size = EH_FRAME_HDR_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;
- if (info->eh_frame_hdr && sec != NULL)
+ eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame");
+ if (eh_frame_sec == NULL)
{
- 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;
+ free (contents);
+ return FALSE;
+ }
- eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame");
- if (eh_frame_sec == NULL)
- {
- free (contents);
- return FALSE;
- }
+ 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);
- 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 (hdr_info->u.dwarf.array
+ && hdr_info->array_count == hdr_info->u.dwarf.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);
- if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count)
+ if (contents[2] != DW_EH_PE_omit)
+ {
+ unsigned int 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++)
{
- /* FDE count encoding. */
- contents[2] = DW_EH_PE_udata4;
- /* Search table encoding. */
- contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4;
+ 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;
}
- else
+ if (overflow)
+ (*info->callbacks->einfo) (_("%P: .eh_frame_hdr entry overflow.\n"));
+ if (overlap)
+ (*info->callbacks->einfo)
+ (_("%P: .eh_frame_hdr refers to overlapping FDEs.\n"));
+ if (overflow || overlap)
{
- contents[2] = DW_EH_PE_omit;
- contents[3] = DW_EH_PE_omit;
+ bfd_set_error (bfd_error_bad_value);
+ retval = FALSE;
}
- bfd_put_32 (abfd, encoded_eh_frame, contents + 4);
+ }
- if (contents[2] != DW_EH_PE_omit)
- {
- unsigned int i;
+ /* 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->u.dwarf.array != NULL)
+ free (hdr_info->u.dwarf.array);
+ return retval;
+}
- 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_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);
- }
- }
+/* 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. */
- /* FIXME: octets_per_byte. */
- retval = bfd_set_section_contents (abfd, sec->output_section, contents,
- (file_ptr) sec->output_offset,
- sec->size);
- free (contents);
- }
- if (hdr_info->array != NULL)
- free (hdr_info->array);
- return retval;
+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. */
projects / deliverable / binutils-gdb.git / blobdiff