/* .eh_frame section optimization.
- Copyright (C) 2001-2015 Free Software Foundation, Inc.
+ Copyright (C) 2001-2020 Free Software Foundation, Inc.
Written by Jakub Jelinek <jakub@redhat.com>.
This file is part of BFD, the Binary File Descriptor library.
return size;
}
-/* Return the size that ENTRY will have in the output. ALIGNMENT is the
- required alignment of ENTRY in bytes. */
+/* Return the size that ENTRY will have in the output. */
static unsigned int
-size_of_output_cie_fde (struct eh_cie_fde *entry, unsigned int alignment)
+size_of_output_cie_fde (struct eh_cie_fde *entry)
{
if (entry->removed)
return 0;
return 4;
return (entry->size
+ extra_augmentation_string_bytes (entry)
- + extra_augmentation_data_bytes (entry)
- + alignment - 1) & -alignment;
+ + extra_augmentation_data_bytes (entry));
+}
+
+/* Return the offset of the FDE or CIE after ENT. */
+
+static unsigned int
+next_cie_fde_offset (const struct eh_cie_fde *ent,
+ const struct eh_cie_fde *last,
+ const asection *sec)
+{
+ while (++ent < last)
+ {
+ if (!ent->removed)
+ return ent->new_offset;
+ }
+ return sec->size;
}
/* Assume that the bytes between *ITER and END are CFA instructions.
hdr_info->array_count--;
hdr_info->u.compact.entries[hdr_info->array_count] = NULL;
i--;
- }
+ }
}
}
REQUIRE (bfd_malloc_and_get_section (abfd, sec, &ehbuf));
- if (sec->size >= 4
- && bfd_get_32 (abfd, ehbuf) == 0
- && cookie->rel == cookie->relend)
- {
- /* Empty .eh_frame section. */
- free (ehbuf);
- return;
- }
-
/* If .eh_frame section size doesn't fit into int, we cannot handle
it (it would need to use 64-bit .eh_frame format anyway). */
REQUIRE (sec->size == (unsigned int) sec->size);
sec_info = (struct eh_frame_sec_info *)
bfd_zmalloc (sizeof (struct eh_frame_sec_info)
- + (num_entries - 1) * sizeof (struct eh_cie_fde));
+ + (num_entries - 1) * sizeof (struct eh_cie_fde));
REQUIRE (sec_info);
/* 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);
+ if (num_cies)
+ {
+ local_cies = (struct cie *) bfd_zmalloc (num_cies * sizeof (*local_cies));
+ REQUIRE (local_cies);
+ }
/* FIXME: octets_per_byte. */
#define ENSURE_NO_RELOCS(buf) \
if (hdr_length == 0)
{
/* A zero-length CIE should only be found at the end of
- the section. */
+ the section, but allow multiple terminators. */
+ while (skip_bytes (&buf, ehbuf + sec->size, 4))
+ REQUIRE (bfd_get_32 (abfd, buf - 4) == 0);
REQUIRE ((bfd_size_type) (buf - ehbuf) == sec->size);
ENSURE_NO_RELOCS (buf);
sec_info->count++;
strcpy (cie->augmentation, (char *) buf);
buf = (bfd_byte *) strchr ((char *) buf, '\0') + 1;
+ this_inf->u.cie.aug_str_len = buf - start - 1;
ENSURE_NO_RELOCS (buf);
if (buf[0] == 'e' && buf[1] == 'h')
{
{
aug++;
REQUIRE (read_uleb128 (&buf, end, &cie->augmentation_size));
- ENSURE_NO_RELOCS (buf);
+ ENSURE_NO_RELOCS (buf);
}
while (*aug != '\0')
switch (*aug++)
{
+ case 'B':
+ break;
case 'L':
REQUIRE (read_byte (&buf, end, &cie->lsda_encoding));
ENSURE_NO_RELOCS (buf);
{
length = -(buf - ehbuf) & (per_width - 1);
REQUIRE (skip_bytes (&buf, end, length));
+ if (per_width == 8)
+ this_inf->u.cie.per_encoding_aligned8 = 1;
}
this_inf->u.cie.personality_offset = buf - start;
ENSURE_NO_RELOCS (buf);
goto free_no_table;
}
}
+ this_inf->u.cie.aug_data_len
+ = buf - start - 1 - this_inf->u.cie.aug_str_len;
/* For shared libraries, try to get rid of as many RELATIVE relocs
as possible. */
- if (info->shared
- && !info->relocatable
+ if (bfd_link_pic (info)
&& (get_elf_backend_data (abfd)
->elf_backend_can_make_relative_eh_frame
(abfd, info, sec)))
buf += initial_insn_length;
ENSURE_NO_RELOCS (buf);
- if (!info->relocatable)
+ if (!bfd_link_relocatable (info))
{
/* Keep info for merging cies. */
this_inf->u.cie.u.full_cie = cie;
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)
&& read_value (abfd, buf - length, length, FALSE) == 0)
{
(*info->callbacks->minfo)
- (_("discarding zero address range FDE in %B(%A).\n"),
+ /* xgettext:c-format */
+ (_("discarding zero address range FDE in %pB(%pA).\n"),
abfd, sec);
this_inf->u.fde.cie_inf = NULL;
}
bfd_byte *p;
this_inf->set_loc = (unsigned int *)
- bfd_malloc ((set_loc_count + 1) * sizeof (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;
elf_section_data (sec)->sec_info = sec_info;
sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME;
- if (!info->relocatable)
+ if (!bfd_link_relocatable (info))
{
/* Keep info for merging cies. */
sec_info->cies = local_cies;
goto success;
free_no_table:
- (*info->callbacks->einfo)
- (_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"),
+ _bfd_error_handler
+ /* xgettext:c-format */
+ (_("error in %pB(%pA); no .eh_frame_hdr table will be created"),
abfd, sec);
hdr_info->u.dwarf.table = FALSE;
- if (sec_info)
- free (sec_info);
+ free (sec_info);
success:
- if (ehbuf)
- free (ehbuf);
- if (local_cies)
- free (local_cies);
+ free (ehbuf);
+ free (local_cies);
#undef REQUIRE
}
if (!sec->rawsize)
sec->rawsize = sec->size;
- bfd_set_section_size (sec->owner, sec, sec->size + 8);
+ bfd_set_section_size (sec, sec->size + 8);
}
/* Finish a pass over all .eh_frame_entry sections. */
}
if (per_binds_local
- && info->shared
- && !info->relocatable
+ && 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)))
return new_cie->cie_inf;
}
+/* For a given OFFSET in SEC, return the delta to the new location
+ after .eh_frame editing. */
+
+static bfd_signed_vma
+offset_adjust (bfd_vma offset, const asection *sec)
+{
+ struct eh_frame_sec_info *sec_info
+ = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info;
+ unsigned int lo, hi, mid;
+ struct eh_cie_fde *ent = NULL;
+ bfd_signed_vma delta;
+
+ lo = 0;
+ hi = sec_info->count;
+ if (hi == 0)
+ return 0;
+
+ while (lo < hi)
+ {
+ mid = (lo + hi) / 2;
+ ent = &sec_info->entry[mid];
+ if (offset < ent->offset)
+ hi = mid;
+ else if (mid + 1 >= hi)
+ break;
+ else if (offset >= ent[1].offset)
+ lo = mid + 1;
+ else
+ break;
+ }
+
+ if (!ent->removed)
+ delta = (bfd_vma) ent->new_offset - (bfd_vma) ent->offset;
+ else if (ent->cie && ent->u.cie.merged)
+ {
+ struct eh_cie_fde *cie = ent->u.cie.u.merged_with;
+ delta = ((bfd_vma) cie->new_offset + cie->u.cie.u.sec->output_offset
+ - (bfd_vma) ent->offset - sec->output_offset);
+ }
+ else
+ {
+ /* Is putting the symbol on the next entry best for a deleted
+ CIE/FDE? */
+ struct eh_cie_fde *last = sec_info->entry + sec_info->count;
+ delta = ((bfd_vma) next_cie_fde_offset (ent, last, sec)
+ - (bfd_vma) ent->offset);
+ return delta;
+ }
+
+ /* Account for editing within this CIE/FDE. */
+ offset -= ent->offset;
+ if (ent->cie)
+ {
+ unsigned int extra
+ = ent->add_augmentation_size + ent->u.cie.add_fde_encoding;
+ if (extra == 0
+ || offset <= 9u + ent->u.cie.aug_str_len)
+ return delta;
+ delta += extra;
+ if (offset <= 9u + ent->u.cie.aug_str_len + ent->u.cie.aug_data_len)
+ return delta;
+ delta += extra;
+ }
+ else
+ {
+ unsigned int ptr_size, width, extra = ent->add_augmentation_size;
+ if (offset <= 12 || extra == 0)
+ return delta;
+ ptr_size = (get_elf_backend_data (sec->owner)
+ ->elf_backend_eh_frame_address_size (sec->owner, sec));
+ width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
+ if (offset <= 8 + 2 * width)
+ return delta;
+ delta += extra;
+ }
+
+ return delta;
+}
+
+/* Adjust a global symbol defined in .eh_frame, so that it stays
+ relative to its original CIE/FDE. It is assumed that a symbol
+ defined at the beginning of a CIE/FDE belongs to that CIE/FDE
+ rather than marking the end of the previous CIE/FDE. This matters
+ when a CIE is merged with a previous CIE, since the symbol is
+ moved to the merged CIE. */
+
+bfd_boolean
+_bfd_elf_adjust_eh_frame_global_symbol (struct elf_link_hash_entry *h,
+ void *arg ATTRIBUTE_UNUSED)
+{
+ asection *sym_sec;
+ bfd_signed_vma delta;
+
+ if (h->root.type != bfd_link_hash_defined
+ && h->root.type != bfd_link_hash_defweak)
+ return TRUE;
+
+ sym_sec = h->root.u.def.section;
+ if (sym_sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME
+ || elf_section_data (sym_sec)->sec_info == NULL)
+ return TRUE;
+
+ delta = offset_adjust (h->root.u.def.value, sym_sec);
+ h->root.u.def.value += delta;
+
+ return TRUE;
+}
+
+/* The same for all local symbols defined in .eh_frame. Returns true
+ if any symbol was changed. */
+
+static int
+adjust_eh_frame_local_symbols (const asection *sec,
+ struct elf_reloc_cookie *cookie)
+{
+ unsigned int shndx;
+ Elf_Internal_Sym *sym;
+ Elf_Internal_Sym *end_sym;
+ int adjusted = 0;
+
+ shndx = elf_section_data (sec)->this_idx;
+ end_sym = cookie->locsyms + cookie->locsymcount;
+ for (sym = cookie->locsyms + 1; sym < end_sym; ++sym)
+ if (sym->st_info <= ELF_ST_INFO (STB_LOCAL, STT_OBJECT)
+ && sym->st_shndx == shndx)
+ {
+ bfd_signed_vma delta = offset_adjust (sym->st_value, sec);
+
+ if (delta != 0)
+ {
+ adjusted = 1;
+ sym->st_value += delta;
+ }
+ }
+ return adjusted;
+}
+
/* This 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
struct eh_cie_fde *ent;
struct eh_frame_sec_info *sec_info;
struct eh_frame_hdr_info *hdr_info;
- unsigned int ptr_size, offset;
+ unsigned int ptr_size, offset, eh_alignment;
+ int changed;
if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME)
return FALSE;
}
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->u.dwarf.table = FALSE;
- (*info->callbacks->einfo)
- (_("%P: FDE encoding in %B(%A) prevents .eh_frame_hdr"
- " table being created.\n"), abfd, sec);
+ /* Only warn if --eh-frame-hdr was specified. */
+ if (info->eh_frame_hdr_type != 0)
+ {
+ if (num_warnings_issued < 10)
+ {
+ _bfd_error_handler
+ /* xgettext:c-format */
+ (_("FDE encoding in %pB(%pA) prevents .eh_frame_hdr"
+ " table being created"), abfd, sec);
+ num_warnings_issued ++;
+ }
+ else if (num_warnings_issued == 10)
+ {
+ _bfd_error_handler
+ (_("further warnings about FDE encoding preventing .eh_frame_hdr generation dropped"));
+ num_warnings_issued ++;
+ }
+ }
}
ent->removed = 0;
hdr_info->u.dwarf.fde_count++;
}
}
- if (sec_info->cies)
- {
- free (sec_info->cies);
- sec_info->cies = NULL;
- }
+ free (sec_info->cies);
+ sec_info->cies = NULL;
+ /* It may be that some .eh_frame input section has greater alignment
+ than other .eh_frame sections. In that case we run the risk of
+ padding with zeros before that section, which would be seen as a
+ zero terminator. Alignment padding must be added *inside* the
+ last FDE instead. For other FDEs we align according to their
+ encoding, in order to align FDE address range entries naturally. */
offset = 0;
+ changed = 0;
for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent)
if (!ent->removed)
{
+ eh_alignment = 4;
+ if (ent->size == 4)
+ ;
+ else if (ent->cie)
+ {
+ if (ent->u.cie.per_encoding_aligned8)
+ eh_alignment = 8;
+ }
+ else
+ {
+ eh_alignment = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
+ if (eh_alignment < 4)
+ eh_alignment = 4;
+ }
+ offset = (offset + eh_alignment - 1) & -eh_alignment;
ent->new_offset = offset;
- offset += size_of_output_cie_fde (ent, ptr_size);
+ if (ent->new_offset != ent->offset)
+ changed = 1;
+ offset += size_of_output_cie_fde (ent);
}
+ eh_alignment = 4;
+ offset = (offset + eh_alignment - 1) & -eh_alignment;
sec->rawsize = sec->size;
sec->size = offset;
- return offset != sec->rawsize;
+ if (sec->size != sec->rawsize)
+ changed = 1;
+
+ if (changed && adjust_eh_frame_local_symbols (sec, cookie))
+ {
+ Elf_Internal_Shdr *symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
+ symtab_hdr->contents = (unsigned char *) cookie->locsyms;
+ }
+ return changed;
}
/* This function is called for .eh_frame_hdr section after
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. */
+ from the .eh_frame_entry sections. */
sec->size = 8;
}
else
{
for (o = abfd->sections; o; o = o->next)
{
- const char *name = bfd_get_section_name (abfd, o);
+ const char *name = bfd_section_name (o);
if (strcmp (name, ".eh_frame_entry")
&& !bfd_is_abs_section (o->output_section))
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);
+ /* xgettext:c-format */
+ _bfd_error_handler (_("%pB: %pA not in order"), sec->owner, sec);
return FALSE;
}
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);
+ /* xgettext:c-format */
+ _bfd_error_handler (_("%pB: %pA invalid input section size"),
+ sec->owner, sec);
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
if (last_addr >= addr + sec->rawsize)
{
- (*_bfd_error_handler) (_("%B: %s points past end of text section"),
- sec->owner, sec->name);
+ /* xgettext:c-format */
+ _bfd_error_handler (_("%pB: %pA points past end of text section"),
+ sec->owner, sec);
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
struct elf_link_hash_table *htab;
struct eh_frame_hdr_info *hdr_info;
unsigned int ptr_size;
- struct eh_cie_fde *ent;
- bfd_size_type sec_size;
+ struct eh_cie_fde *ent, *last_ent;
if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME)
/* FIXME: octets_per_byte. */
{
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
+ bfd_malloc (hdr_info->u.dwarf.fde_count
* sizeof (*hdr_info->u.dwarf.array));
}
if (hdr_info->u.dwarf.array == NULL)
if (!ent->removed && ent->new_offset < ent->offset)
memmove (contents + ent->new_offset, contents + ent->offset, ent->size);
- for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent)
+ last_ent = sec_info->entry + sec_info->count;
+ for (ent = sec_info->entry; ent < last_ent; ++ent)
{
unsigned char *buf, *end;
unsigned int new_size;
if (ent->size == 4)
{
/* Any terminating FDE must be at the end of the section. */
- BFD_ASSERT (ent == sec_info->entry + sec_info->count - 1);
+ BFD_ASSERT (ent == last_ent - 1);
continue;
}
buf = contents + ent->new_offset;
end = buf + ent->size;
- new_size = size_of_output_cie_fde (ent, ptr_size);
+ new_size = next_cie_fde_offset (ent, last_ent, sec) - ent->new_offset;
/* Update the size. It may be shrinked. */
bfd_put_32 (abfd, new_size - 4, buf);
|| ent->u.cie.per_encoding_relative)
{
char *aug;
- unsigned int action, extra_string, extra_data;
+ unsigned int version, action, extra_string, extra_data;
unsigned int per_width, per_encoding;
/* Need to find 'R' or 'L' augmentation's argument and modify
extra_string = extra_augmentation_string_bytes (ent);
extra_data = extra_augmentation_data_bytes (ent);
- /* Skip length, id and version. */
- buf += 9;
+ /* Skip length, id. */
+ buf += 8;
+ version = *buf++;
aug = (char *) buf;
buf += strlen (aug) + 1;
skip_leb128 (&buf, end);
skip_leb128 (&buf, end);
- skip_leb128 (&buf, end);
+ if (version == 1)
+ skip_bytes (&buf, end, 1);
+ else
+ skip_leb128 (&buf, end);
if (*aug == 'z')
{
/* The uleb128 will always be a single byte for the kind
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)
+ if (bfd_link_relocatable (info))
continue;
buf += 4;
width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
address += elf_gp (abfd);
break;
default:
- (*info->callbacks->einfo)
- (_("%P: DW_EH_PE_datarel unspecified"
- " for this architecture.\n"));
+ _bfd_error_handler
+ (_("DW_EH_PE_datarel unspecified"
+ " for this architecture"));
/* Fall thru */
case bfd_arch_frv:
case bfd_arch_i386:
+ case bfd_arch_nios2:
BFD_ASSERT (htab->hgot != NULL
&& ((htab->hgot->root.type
== bfd_link_hash_defined)
}
}
- /* We don't align the section to its section alignment since the
- runtime library only expects all CIE/FDE records aligned at
- the pointer size. _bfd_elf_discard_section_eh_frame should
- have padded CIE/FDE records to multiple of pointer size with
- size_of_output_cie_fde. */
- 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 bfd_set_section_contents (abfd, sec->output_section,
contents, (file_ptr) sec->output_offset,
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);
+ _bfd_error_handler
+ (_("invalid output section for .eh_frame_entry: %pA"),
+ sec->output_section);
return FALSE;
}
sec->output_offset = offset;
p->offset = p->u.indirect.section->output_offset;
if (p->next != NULL)
- i--;
+ i--;
}
if (i != 0)
{
- (*_bfd_error_handler)
- (_("Invalid contents in %s section"), osec->name);
+ _bfd_error_handler
+ (_("invalid contents in %pA section"), osec);
return FALSE;
}
/* The .eh_frame_hdr format for DWARF frames:
ubyte version (currently 1)
- ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of
+ ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of
.eh_frame section)
ubyte fde_count_enc (DW_EH_PE_* encoding of total FDE count
number (or DW_EH_PE_omit if there is no
overlap = TRUE;
}
if (overflow)
- (*info->callbacks->einfo) (_("%P: .eh_frame_hdr entry overflow.\n"));
+ _bfd_error_handler (_(".eh_frame_hdr entry overflow"));
if (overlap)
- (*info->callbacks->einfo)
- (_("%P: .eh_frame_hdr refers to overlapping FDEs.\n"));
+ _bfd_error_handler (_(".eh_frame_hdr refers to overlapping FDEs"));
if (overflow || overlap)
{
bfd_set_error (bfd_error_bad_value);
retval = FALSE;
free (contents);
- if (hdr_info->u.dwarf.array != NULL)
- free (hdr_info->u.dwarf.array);
+ free (hdr_info->u.dwarf.array);
return retval;
}
/* Return the width of FDE addresses. This is the default implementation. */
unsigned int
-_bfd_elf_eh_frame_address_size (bfd *abfd, asection *sec ATTRIBUTE_UNUSED)
+_bfd_elf_eh_frame_address_size (bfd *abfd, const asection *sec ATTRIBUTE_UNUSED)
{
return elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 ? 8 : 4;
}
projects / thirdparty / binutils-gdb.git / blobdiff