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)
{
#define REQUIRE(COND) \
do \
if (!(COND)) \
goto free_no_table; \
while (0)
bfd_byte *ehbuf = NULL, *buf;
bfd_byte *last_cie, *last_fde;
struct eh_cie_fde *ent, *last_cie_inf, *this_inf;
struct cie_header hdr;
struct cie cie;
struct elf_link_hash_table *htab;
struct eh_frame_hdr_info *hdr_info;
struct eh_frame_sec_info *sec_info = NULL;
unsigned int cie_usage_count, offset;
unsigned int ptr_size;
if (sec->size == 0)
{
/* This file does not contain .eh_frame information. */
return FALSE;
}
if ((sec->output_section != NULL
&& 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;
}
htab = elf_hash_table (info);
hdr_info = &htab->eh_info;
/* Read the frame unwind information from abfd. */
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 FALSE;
}
/* 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);
ptr_size = (get_elf_backend_data (abfd)
->elf_backend_eh_frame_address_size (abfd, sec));
REQUIRE (ptr_size != 0);
buf = ehbuf;
last_cie = NULL;
last_cie_inf = NULL;
memset (&cie, 0, sizeof (cie));
cie_usage_count = 0;
sec_info = bfd_zmalloc (sizeof (struct eh_frame_sec_info)
+ 99 * sizeof (struct eh_cie_fde));
REQUIRE (sec_info);
sec_info->alloced = 100;
#define ENSURE_NO_RELOCS(buf) \
REQUIRE (!(cookie->rel < cookie->relend \
&& (cookie->rel->r_offset \
< (bfd_size_type) ((buf) - ehbuf)) \
&& cookie->rel->r_info != 0))
#define SKIP_RELOCS(buf) \
while (cookie->rel < cookie->relend \
&& (cookie->rel->r_offset \
< (bfd_size_type) ((buf) - ehbuf))) \
cookie->rel++
#define GET_RELOC(buf) \
((cookie->rel < cookie->relend \
&& (cookie->rel->r_offset \
== (bfd_size_type) ((buf) - ehbuf))) \
? cookie->rel : NULL)
for (;;)
{
char *aug;
bfd_byte *start, *end, *insns;
bfd_size_type length;
if (sec_info->count == sec_info->alloced)
{
struct eh_cie_fde *old_entry = sec_info->entry;
sec_info = bfd_realloc (sec_info,
sizeof (struct eh_frame_sec_info)
+ ((sec_info->alloced + 99)
* sizeof (struct eh_cie_fde)));
REQUIRE (sec_info);
memset (&sec_info->entry[sec_info->alloced], 0,
100 * sizeof (struct eh_cie_fde));
sec_info->alloced += 100;
/* Now fix any pointers into the array. */
if (last_cie_inf >= old_entry
&& last_cie_inf < old_entry + sec_info->count)
last_cie_inf = sec_info->entry + (last_cie_inf - old_entry);
}
this_inf = sec_info->entry + sec_info->count;
last_fde = buf;
/* If we are at the end of the section, we still need to decide
on whether to output or discard last encountered CIE (if any). */
if ((bfd_size_type) (buf - ehbuf) == sec->size)
{
hdr.length = 0;
hdr.id = (unsigned int) -1;
end = buf;
}
else
{
/* 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;
if (hdr.length == 0)
{
/* A zero-length CIE should only be found at the end of
the section. */
REQUIRE ((bfd_size_type) (buf - ehbuf) == sec->size);
ENSURE_NO_RELOCS (buf);
sec_info->count++;
/* Now just finish last encountered CIE processing and break
the loop. */
hdr.id = (unsigned int) -1;
}
else
{
REQUIRE (skip_bytes (&buf, end, 4));
hdr.id = bfd_get_32 (abfd, buf - 4);
REQUIRE (hdr.id != (unsigned int) -1);
}
}
if (hdr.id == 0 || hdr.id == (unsigned int) -1)
{
unsigned int initial_insn_length;
/* CIE */
if (last_cie != NULL)
{
/* Now check if this CIE is identical to the last CIE,
in which case we can remove it provided we adjust
all FDEs. Also, it can be removed if we have removed
all FDEs using it. */
if ((!info->relocatable
&& hdr_info->last_cie_sec
&& (sec->output_section
== hdr_info->last_cie_sec->output_section)
&& cie_compare (&cie, &hdr_info->last_cie) == 0)
|| cie_usage_count == 0)
last_cie_inf->removed = 1;
else
{
hdr_info->last_cie = cie;
hdr_info->last_cie_sec = sec;
last_cie_inf->make_relative = cie.make_relative;
last_cie_inf->make_lsda_relative = cie.make_lsda_relative;
last_cie_inf->per_encoding_relative
= (cie.per_encoding & 0x70) == DW_EH_PE_pcrel;
}
}
if (hdr.id == (unsigned int) -1)
break;
last_cie_inf = this_inf;
this_inf->cie = 1;
cie_usage_count = 0;
memset (&cie, 0, sizeof (cie));
cie.hdr = hdr;
REQUIRE (read_byte (&buf, end, &cie.version));
/* Cannot handle unknown versions. */
REQUIRE (cie.version == 1 || cie.version == 3);
REQUIRE (strlen ((char *) buf) < sizeof (cie.augmentation));
strcpy (cie.augmentation, (char *) buf);
buf = (bfd_byte *) strchr ((char *) buf, '\0') + 1;
ENSURE_NO_RELOCS (buf);
if (buf[0] == 'e' && buf[1] == 'h')
{
/* GCC < 3.0 .eh_frame CIE */
/* We cannot merge "eh" CIEs because __EXCEPTION_TABLE__
is private to each CIE, so we don't need it for anything.
Just skip it. */
REQUIRE (skip_bytes (&buf, end, ptr_size));
SKIP_RELOCS (buf);
}
REQUIRE (read_uleb128 (&buf, end, &cie.code_align));
REQUIRE (read_sleb128 (&buf, end, &cie.data_align));
if (cie.version == 1)
{
REQUIRE (buf < end);
cie.ra_column = *buf++;
}
else
REQUIRE (read_uleb128 (&buf, end, &cie.ra_column));
ENSURE_NO_RELOCS (buf);
cie.lsda_encoding = DW_EH_PE_omit;
cie.fde_encoding = DW_EH_PE_omit;
cie.per_encoding = DW_EH_PE_omit;
aug = cie.augmentation;
if (aug[0] != 'e' || aug[1] != 'h')
{
if (*aug == 'z')
{
aug++;
REQUIRE (read_uleb128 (&buf, end, &cie.augmentation_size));
ENSURE_NO_RELOCS (buf);
}
while (*aug != '\0')
switch (*aug++)
{
case 'L':
REQUIRE (read_byte (&buf, end, &cie.lsda_encoding));
ENSURE_NO_RELOCS (buf);
REQUIRE (get_DW_EH_PE_width (cie.lsda_encoding, ptr_size));
break;
case 'R':
REQUIRE (read_byte (&buf, end, &cie.fde_encoding));
ENSURE_NO_RELOCS (buf);
REQUIRE (get_DW_EH_PE_width (cie.fde_encoding, ptr_size));
break;
case 'P':
{
int per_width;
REQUIRE (read_byte (&buf, end, &cie.per_encoding));
per_width = get_DW_EH_PE_width (cie.per_encoding,
ptr_size);
REQUIRE (per_width);
if ((cie.per_encoding & 0xf0) == DW_EH_PE_aligned)
{
length = -(buf - ehbuf) & (per_width - 1);
REQUIRE (skip_bytes (&buf, end, length));
}
ENSURE_NO_RELOCS (buf);
/* Ensure we have a reloc here, against
a global symbol. */
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)
{
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;
}
/* Cope with MIPS-style composite relocations. */
do
cookie->rel++;
while (GET_RELOC (buf) != NULL);
}
REQUIRE (skip_bytes (&buf, end, per_width));
}
break;
default:
/* Unrecognized augmentation. Better bail out. */
goto free_no_table;
}
}
/* For shared libraries, try to get rid of as many RELATIVE relocs
as possible. */
if (info->shared
&& (get_elf_backend_data (abfd)
->elf_backend_can_make_relative_eh_frame
(abfd, info, sec)))
{
if ((cie.fde_encoding & 0xf0) == DW_EH_PE_absptr)
cie.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. */
else if (cie.fde_encoding == DW_EH_PE_omit
&& (cie.per_encoding & 0xf0) != DW_EH_PE_aligned)
{
if (*cie.augmentation == 0)
this_inf->add_augmentation_size = 1;
this_inf->add_fde_encoding = 1;
cie.make_relative = 1;
}
}
if (info->shared
&& (get_elf_backend_data (abfd)
->elf_backend_can_make_lsda_relative_eh_frame
(abfd, info, sec))
&& (cie.lsda_encoding & 0xf0) == DW_EH_PE_absptr)
cie.make_lsda_relative = 1;
/* If FDE encoding was not specified, it defaults to
DW_EH_absptr. */
if (cie.fde_encoding == DW_EH_PE_omit)
cie.fde_encoding = DW_EH_PE_absptr;
initial_insn_length = end - buf;
if (initial_insn_length <= 50)
{
cie.initial_insn_length = initial_insn_length;
memcpy (cie.initial_instructions, buf, initial_insn_length);
}
insns = buf;
buf += initial_insn_length;
ENSURE_NO_RELOCS (buf);
last_cie = last_fde;
}
else
{
/* Ensure this FDE uses the last CIE encountered. */
REQUIRE (last_cie);
REQUIRE (hdr.id == (unsigned int) (buf - 4 - last_cie));
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
{
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;
}
cie_usage_count++;
hdr_info->fde_count++;
}
/* Skip the initial location and address range. */
start = buf;
length = get_DW_EH_PE_width (cie.fde_encoding, ptr_size);
REQUIRE (skip_bytes (&buf, end, 2 * length));
/* Skip the augmentation size, if present. */
if (cie.augmentation[0] == 'z')
REQUIRE (read_uleb128 (&buf, end, &length));
else
length = 0;
/* Of the supported augmentation characters above, only 'L'
adds augmentation data to the FDE. This code would need to
be adjusted if any future augmentations do the same thing. */
if (cie.lsda_encoding != DW_EH_PE_omit)
{
this_inf->lsda_offset = buf - start;
/* If there's no 'z' augmentation, we don't know where the
CFA insns begin. Assume no padding. */
if (cie.augmentation[0] != 'z')
length = end - buf;
}
/* Skip over the augmentation data. */
REQUIRE (skip_bytes (&buf, end, length));
insns = buf;
buf = last_fde + 4 + hdr.length;
SKIP_RELOCS (buf);
}
/* Try to interpret the CFA instructions and find the first
padding nop. Shrink this_inf's size so that it doesn't
including the padding. */
length = get_DW_EH_PE_width (cie.fde_encoding, ptr_size);
insns = skip_non_nops (insns, end, length);
if (insns != 0)
this_inf->size -= end - insns;
this_inf->fde_encoding = cie.fde_encoding;
this_inf->lsda_encoding = cie.lsda_encoding;
sec_info->count++;
}
elf_section_data (sec)->sec_info = sec_info;
sec->sec_info_type = ELF_INFO_TYPE_EH_FRAME;
/* Ok, now we can assign new offsets. */
offset = 0;
last_cie_inf = hdr_info->last_cie_inf;
for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent)
if (!ent->removed)
{
if (ent->cie)
last_cie_inf = ent;
else
ent->cie_inf = last_cie_inf;
ent->new_offset = offset;
offset += size_of_output_cie_fde (ent, ptr_size);
}
hdr_info->last_cie_inf = last_cie_inf;
/* Resize the sec as needed. */
sec->rawsize = sec->size;
sec->size = offset;
if (sec->size == 0)
sec->flags |= SEC_EXCLUDE;
free (ehbuf);
return offset != sec->rawsize;
free_no_table:
if (ehbuf)
free (ehbuf);
if (sec_info)
free (sec_info);
hdr_info->table = FALSE;
hdr_info->last_cie.hdr.length = 0;
return FALSE;
#undef REQUIRE
}
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)
{
bfd_byte *ehbuf = NULL, *buf;
bfd_byte *last_cie, *last_fde;
struct cie_header hdr;
struct cie cie;
struct elf_link_hash_table *htab;
struct eh_frame_hdr_info *hdr_info;
struct eh_frame_sec_info *sec_info = NULL;
unsigned int leb128_tmp;
unsigned int cie_usage_count, last_cie_ndx, i, offset;
unsigned int make_relative, make_lsda_relative;
bfd_size_type new_size;
unsigned int ptr_size;
if (sec->_raw_size == 0)
{
/* This file does not contain .eh_frame information. */
return FALSE;
}
if ((sec->output_section != NULL
&& 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;
}
htab = elf_hash_table (info);
hdr_info = &htab->eh_info;
/* Read the frame unwind information from abfd. */
ehbuf = bfd_malloc (sec->_raw_size);
if (ehbuf == NULL)
goto free_no_table;
if (! bfd_get_section_contents (abfd, sec, ehbuf, 0, sec->_raw_size))
goto free_no_table;
if (sec->_raw_size >= 4
&& bfd_get_32 (abfd, ehbuf) == 0
&& cookie->rel == cookie->relend)
{
/* Empty .eh_frame section. */
free (ehbuf);
return FALSE;
}
/* 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). */
if (sec->_raw_size != (unsigned int) sec->_raw_size)
goto free_no_table;
ptr_size = (elf_elfheader (abfd)->e_ident[EI_CLASS]
== ELFCLASS64) ? 8 : 4;
buf = ehbuf;
last_cie = NULL;
last_cie_ndx = 0;
memset (&cie, 0, sizeof (cie));
cie_usage_count = 0;
new_size = sec->_raw_size;
make_relative = hdr_info->last_cie.make_relative;
make_lsda_relative = hdr_info->last_cie.make_lsda_relative;
sec_info = bfd_zmalloc (sizeof (struct eh_frame_sec_info)
+ 99 * sizeof (struct eh_cie_fde));
if (sec_info == NULL)
goto free_no_table;
sec_info->alloced = 100;
#define ENSURE_NO_RELOCS(buf) \
if (cookie->rel < cookie->relend \
&& (cookie->rel->r_offset \
< (bfd_size_type) ((buf) - ehbuf)) \
&& cookie->rel->r_info != 0) \
goto free_no_table
#define SKIP_RELOCS(buf) \
while (cookie->rel < cookie->relend \
&& (cookie->rel->r_offset \
< (bfd_size_type) ((buf) - ehbuf))) \
cookie->rel++
#define GET_RELOC(buf) \
((cookie->rel < cookie->relend \
&& (cookie->rel->r_offset \
== (bfd_size_type) ((buf) - ehbuf))) \
? cookie->rel : NULL)
for (;;)
{
unsigned char *aug;
if (sec_info->count == sec_info->alloced)
{
sec_info = bfd_realloc (sec_info,
sizeof (struct eh_frame_sec_info)
+ (sec_info->alloced + 99)
* sizeof (struct eh_cie_fde));
if (sec_info == NULL)
goto free_no_table;
memset (&sec_info->entry[sec_info->alloced], 0,
100 * sizeof (struct eh_cie_fde));
sec_info->alloced += 100;
}
last_fde = buf;
/* If we are at the end of the section, we still need to decide
on whether to output or discard last encountered CIE (if any). */
if ((bfd_size_type) (buf - ehbuf) == sec->_raw_size)
hdr.id = (unsigned int) -1;
else
{
if ((bfd_size_type) (buf + 4 - ehbuf) > sec->_raw_size)
/* No space for CIE/FDE header length. */
goto free_no_table;
hdr.length = bfd_get_32 (abfd, buf);
if (hdr.length == 0xffffffff)
/* 64-bit .eh_frame is not supported. */
goto free_no_table;
buf += 4;
if ((bfd_size_type) (buf - ehbuf) + hdr.length > sec->_raw_size)
/* CIE/FDE not contained fully in this .eh_frame input section. */
goto free_no_table;
sec_info->entry[sec_info->count].offset = last_fde - ehbuf;
sec_info->entry[sec_info->count].size = 4 + hdr.length;
if (hdr.length == 0)
{
/* CIE with length 0 must be only the last in the section. */
if ((bfd_size_type) (buf - ehbuf) < sec->_raw_size)
goto free_no_table;
ENSURE_NO_RELOCS (buf);
sec_info->count++;
/* Now just finish last encountered CIE processing and break
the loop. */
hdr.id = (unsigned int) -1;
}
else
{
hdr.id = bfd_get_32 (abfd, buf);
buf += 4;
if (hdr.id == (unsigned int) -1)
goto free_no_table;
}
}
if (hdr.id == 0 || hdr.id == (unsigned int) -1)
{
unsigned int initial_insn_length;
/* CIE */
if (last_cie != NULL)
{
/* Now check if this CIE is identical to the last CIE,
in which case we can remove it provided we adjust
all FDEs. Also, it can be removed if we have removed
all FDEs using it. */
if ((!info->relocatable
&& hdr_info->last_cie_sec
&& (sec->output_section
== hdr_info->last_cie_sec->output_section)
&& cie_compare (&cie, &hdr_info->last_cie) == 0)
|| cie_usage_count == 0)
{
new_size -= cie.hdr.length + 4;
sec_info->entry[last_cie_ndx].removed = 1;
sec_info->entry[last_cie_ndx].sec = hdr_info->last_cie_sec;
sec_info->entry[last_cie_ndx].new_offset
= hdr_info->last_cie_offset;
}
else
{
hdr_info->last_cie = cie;
hdr_info->last_cie_sec = sec;
hdr_info->last_cie_offset = last_cie - ehbuf;
sec_info->entry[last_cie_ndx].make_relative
= cie.make_relative;
sec_info->entry[last_cie_ndx].make_lsda_relative
= cie.make_lsda_relative;
sec_info->entry[last_cie_ndx].per_encoding_relative
= (cie.per_encoding & 0x70) == DW_EH_PE_pcrel;
}
}
if (hdr.id == (unsigned int) -1)
break;
last_cie_ndx = sec_info->count;
sec_info->entry[sec_info->count].cie = 1;
cie_usage_count = 0;
memset (&cie, 0, sizeof (cie));
cie.hdr = hdr;
cie.version = *buf++;
/* Cannot handle unknown versions. */
if (cie.version != 1)
goto free_no_table;
if (strlen (buf) > sizeof (cie.augmentation) - 1)
goto free_no_table;
strcpy (cie.augmentation, buf);
buf = strchr (buf, '\0') + 1;
ENSURE_NO_RELOCS (buf);
if (buf[0] == 'e' && buf[1] == 'h')
{
/* GCC < 3.0 .eh_frame CIE */
/* We cannot merge "eh" CIEs because __EXCEPTION_TABLE__
is private to each CIE, so we don't need it for anything.
Just skip it. */
buf += ptr_size;
SKIP_RELOCS (buf);
}
read_uleb128 (cie.code_align, buf);
read_sleb128 (cie.data_align, buf);
/* Note - in DWARF2 the return address column is an unsigned byte.
In DWARF3 it is a ULEB128. We are following DWARF3. For most
ports this will not matter as the value will be less than 128.
For the others (eg FRV, SH, MMIX, IA64) they need a fixed GCC
which conforms to the DWARF3 standard. */
read_uleb128 (cie.ra_column, buf);
ENSURE_NO_RELOCS (buf);
cie.lsda_encoding = DW_EH_PE_omit;
cie.fde_encoding = DW_EH_PE_omit;
cie.per_encoding = DW_EH_PE_omit;
aug = cie.augmentation;
if (aug[0] != 'e' || aug[1] != 'h')
{
if (*aug == 'z')
{
aug++;
read_uleb128 (cie.augmentation_size, buf);
ENSURE_NO_RELOCS (buf);
}
while (*aug != '\0')
switch (*aug++)
{
case 'L':
cie.lsda_encoding = *buf++;
ENSURE_NO_RELOCS (buf);
if (get_DW_EH_PE_width (cie.lsda_encoding, ptr_size) == 0)
goto free_no_table;
break;
case 'R':
cie.fde_encoding = *buf++;
ENSURE_NO_RELOCS (buf);
if (get_DW_EH_PE_width (cie.fde_encoding, ptr_size) == 0)
goto free_no_table;
break;
case 'P':
{
int per_width;
cie.per_encoding = *buf++;
per_width = get_DW_EH_PE_width (cie.per_encoding,
ptr_size);
if (per_width == 0)
goto free_no_table;
if ((cie.per_encoding & 0xf0) == DW_EH_PE_aligned)
buf = (ehbuf
+ ((buf - ehbuf + per_width - 1)
& ~((bfd_size_type) per_width - 1)));
ENSURE_NO_RELOCS (buf);
/* Ensure we have a reloc here, against
a global symbol. */
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)
{
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;
}
cookie->rel++;
}
buf += per_width;
}
break;
default:
/* Unrecognized augmentation. Better bail out. */
goto free_no_table;
}
}
/* For shared libraries, try to get rid of as many RELATIVE relocs
as possible. */
if (info->shared
&& (get_elf_backend_data (abfd)
->elf_backend_can_make_relative_eh_frame
(abfd, info, sec))
&& (cie.fde_encoding & 0xf0) == DW_EH_PE_absptr)
cie.make_relative = 1;
if (info->shared
&& (get_elf_backend_data (abfd)
->elf_backend_can_make_lsda_relative_eh_frame
(abfd, info, sec))
&& (cie.lsda_encoding & 0xf0) == DW_EH_PE_absptr)
cie.make_lsda_relative = 1;
/* If FDE encoding was not specified, it defaults to
DW_EH_absptr. */
if (cie.fde_encoding == DW_EH_PE_omit)
cie.fde_encoding = DW_EH_PE_absptr;
initial_insn_length = cie.hdr.length - (buf - last_fde - 4);
if (initial_insn_length <= 50)
{
cie.initial_insn_length = initial_insn_length;
memcpy (cie.initial_instructions, buf, initial_insn_length);
}
buf += initial_insn_length;
ENSURE_NO_RELOCS (buf);
last_cie = last_fde;
}
else
{
/* Ensure this FDE uses the last CIE encountered. */
if (last_cie == NULL
|| hdr.id != (unsigned int) (buf - 4 - last_cie))
goto free_no_table;
ENSURE_NO_RELOCS (buf);
if (GET_RELOC (buf) == NULL)
/* This should not happen. */
goto free_no_table;
if ((*reloc_symbol_deleted_p) (buf - ehbuf, cookie))
{
/* This is a FDE against a discarded section. It should
be deleted. */
new_size -= hdr.length + 4;
sec_info->entry[sec_info->count].removed = 1;
}
else
{
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;
}
cie_usage_count++;
hdr_info->fde_count++;
}
if (cie.lsda_encoding != DW_EH_PE_omit)
{
unsigned int dummy;
aug = buf;
buf += 2 * get_DW_EH_PE_width (cie.fde_encoding, ptr_size);
if (cie.augmentation[0] == 'z')
read_uleb128 (dummy, buf);
/* If some new augmentation data is added before LSDA
in FDE augmentation area, this need to be adjusted. */
sec_info->entry[sec_info->count].lsda_offset = (buf - aug);
}
buf = last_fde + 4 + hdr.length;
SKIP_RELOCS (buf);
}
sec_info->entry[sec_info->count].fde_encoding = cie.fde_encoding;
sec_info->entry[sec_info->count].lsda_encoding = cie.lsda_encoding;
sec_info->count++;
}
elf_section_data (sec)->sec_info = sec_info;
sec->sec_info_type = ELF_INFO_TYPE_EH_FRAME;
/* Ok, now we can assign new offsets. */
offset = 0;
last_cie_ndx = 0;
for (i = 0; i < sec_info->count; i++)
{
if (! sec_info->entry[i].removed)
{
sec_info->entry[i].new_offset = offset;
offset += sec_info->entry[i].size;
if (sec_info->entry[i].cie)
{
last_cie_ndx = i;
make_relative = sec_info->entry[i].make_relative;
make_lsda_relative = sec_info->entry[i].make_lsda_relative;
}
else
{
sec_info->entry[i].make_relative = make_relative;
sec_info->entry[i].make_lsda_relative = make_lsda_relative;
sec_info->entry[i].per_encoding_relative = 0;
}
}
else if (sec_info->entry[i].cie && sec_info->entry[i].sec == sec)
{
/* Need to adjust new_offset too. */
BFD_ASSERT (sec_info->entry[last_cie_ndx].offset
== sec_info->entry[i].new_offset);
sec_info->entry[i].new_offset
= sec_info->entry[last_cie_ndx].new_offset;
}
}
if (hdr_info->last_cie_sec == sec)
{
BFD_ASSERT (sec_info->entry[last_cie_ndx].offset
== hdr_info->last_cie_offset);
hdr_info->last_cie_offset = sec_info->entry[last_cie_ndx].new_offset;
}
/* FIXME: Currently it is not possible to shrink sections to zero size at
this point, so build a fake minimal CIE. */
if (new_size == 0)
new_size = 16;
/* Shrink the sec as needed. */
sec->_cooked_size = new_size;
if (sec->_cooked_size == 0)
sec->flags |= SEC_EXCLUDE;
free (ehbuf);
return new_size != sec->_raw_size;
free_no_table:
if (ehbuf)
free (ehbuf);
if (sec_info)
free (sec_info);
hdr_info->table = FALSE;
hdr_info->last_cie.hdr.length = 0;
return FALSE;
}
