/* .eh_frame section optimization.
- Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007
+ Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
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
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;
}
return last;
}
+/* Convert absolute encoding ENCODING into PC-relative form.
+ SIZE is the size of a pointer. */
+
+static unsigned char
+make_pc_relative (unsigned char encoding, unsigned int ptr_size)
+{
+ if ((encoding & 0x7f) == DW_EH_PE_absptr)
+ switch (ptr_size)
+ {
+ case 2:
+ encoding |= DW_EH_PE_sdata2;
+ break;
+ case 4:
+ encoding |= DW_EH_PE_sdata4;
+ break;
+ case 8:
+ encoding |= DW_EH_PE_sdata8;
+ break;
+ }
+ return encoding | DW_EH_PE_pcrel;
+}
+
/* Called before calling _bfd_elf_parse_eh_frame on every input bfd's
.eh_frame section. */
REQUIRE (skip_bytes (&buf, end, hdr_length - 4));
}
- sec_info = bfd_zmalloc (sizeof (struct eh_frame_sec_info)
- + (num_entries - 1) * sizeof (struct eh_cie_fde));
+ 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);
/* We need to have a "struct cie" for each CIE in this section. */
- local_cies = bfd_zmalloc (num_cies * sizeof (*local_cies));
+ 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 \
REQUIRE (read_byte (&buf, end, &cie->version));
/* Cannot handle unknown versions. */
- REQUIRE (cie->version == 1 || cie->version == 3);
+ REQUIRE (cie->version == 1
+ || cie->version == 3
+ || cie->version == 4);
REQUIRE (strlen ((char *) buf) < sizeof (cie->augmentation));
strcpy (cie->augmentation, (char *) buf);
REQUIRE (skip_bytes (&buf, end, ptr_size));
SKIP_RELOCS (buf);
}
+ if (cie->version >= 4)
+ {
+ REQUIRE (buf + 1 < end);
+ REQUIRE (buf[0] == ptr_size);
+ REQUIRE (buf[1] == 0);
+ buf += 2;
+ }
REQUIRE (read_uleb128 (&buf, end, &cie->code_align));
REQUIRE (read_sleb128 (&buf, end, &cie->data_align));
if (cie->version == 1)
per_width = get_DW_EH_PE_width (cie->per_encoding,
ptr_size);
REQUIRE (per_width);
- if ((cie->per_encoding & 0xf0) == DW_EH_PE_aligned)
+ if ((cie->per_encoding & 0x70) == DW_EH_PE_aligned)
{
length = -(buf - ehbuf) & (per_width - 1);
REQUIRE (skip_bytes (&buf, end, length));
}
+ this_inf->u.cie.personality_offset = buf - start;
ENSURE_NO_RELOCS (buf);
/* Ensure we have a reloc here. */
REQUIRE (GET_RELOC (buf));
->elf_backend_can_make_relative_eh_frame
(abfd, info, sec)))
{
- if ((cie->fde_encoding & 0xf0) == DW_EH_PE_absptr)
+ if ((cie->fde_encoding & 0x70) == DW_EH_PE_absptr)
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. */
else if (cie->fde_encoding == DW_EH_PE_omit
- && (cie->per_encoding & 0xf0) != DW_EH_PE_aligned)
+ && (cie->per_encoding & 0x70) != DW_EH_PE_aligned)
{
if (*cie->augmentation == 0)
this_inf->add_augmentation_size = 1;
this_inf->u.cie.add_fde_encoding = 1;
this_inf->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->can_make_lsda_relative = 1;
+ if ((cie->lsda_encoding & 0x70) == DW_EH_PE_absptr)
+ cie->can_make_lsda_relative = 1;
+ }
/* If FDE encoding was not specified, it defaults to
DW_EH_absptr. */
/* Chain together the FDEs for each section. */
rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie);
- REQUIRE (rsec && rsec->owner == abfd);
- this_inf->u.fde.next_for_section = elf_fde_list (rsec);
- elf_fde_list (rsec) = this_inf;
+ /* RSEC will be NULL if FDE was cleared out as it was belonging to
+ a discarded SHT_GROUP. */
+ if (rsec)
+ {
+ 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. */
start = buf;
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);
}
cie->length -= end - insns_end;
}
if (set_loc_count
- && ((cie->fde_encoding & 0xf0) == DW_EH_PE_pcrel
+ && ((cie->fde_encoding & 0x70) == DW_EH_PE_pcrel
|| 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;
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;
relocations in REL. */
static struct eh_cie_fde *
-find_merged_cie (bfd *abfd, asection *sec,
+find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec,
struct eh_frame_hdr_info *hdr_info,
struct elf_reloc_cookie *cookie,
struct eh_cie_fde *cie_inf)
if (cie->per_encoding != DW_EH_PE_omit)
{
+ bfd_boolean per_binds_local;
+
/* Work out the address of personality routine, either as an absolute
value or as a symbol. */
rel = cookie->rels + cie->personality.reloc_index;
h = (struct elf_link_hash_entry *) h->root.u.i.link;
cie->personality.h = h;
+ per_binds_local = SYMBOL_REFERENCES_LOCAL (info, h);
}
else
{
cie->personality.val = (sym->st_value
+ sym_sec->output_offset
+ sym_sec->output_section->vma);
+ per_binds_local = TRUE;
+ }
+
+ if (per_binds_local
+ && info->shared
+ && (cie->per_encoding & 0x70) == DW_EH_PE_absptr
+ && (get_elf_backend_data (abfd)
+ ->elf_backend_can_make_relative_eh_frame (abfd, info, sec)))
+ {
+ cie_inf->u.cie.make_per_encoding_relative = 1;
+ cie_inf->u.cie.per_encoding_relative = 1;
}
}
if (new_cie == NULL)
{
/* Keep CIE_INF and record it in the hash table. */
- new_cie = malloc (sizeof (struct cie));
+ new_cie = (struct cie *) malloc (sizeof (struct cie));
if (new_cie == NULL)
return cie_inf;
else 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))
{
if (info->shared
- && (((ent->fde_encoding & 0xf0) == DW_EH_PE_absptr
+ && (((ent->fde_encoding & 0x70) == DW_EH_PE_absptr
&& ent->make_relative == 0)
- || (ent->fde_encoding & 0xf0) == DW_EH_PE_aligned))
+ || (ent->fde_encoding & 0x70) == DW_EH_PE_aligned))
{
/* If a shared library uses absolute pointers
which we cannot turn into PC relative,
}
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);
+ ent->u.fde.cie_inf = find_merged_cie (abfd, info, sec, hdr_info,
+ cookie, ent->u.fde.cie_inf);
}
}
bfd_vma
_bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED,
- struct bfd_link_info *info,
+ struct bfd_link_info *info ATTRIBUTE_UNUSED,
asection *sec,
bfd_vma offset)
{
struct eh_frame_sec_info *sec_info;
- struct elf_link_hash_table *htab;
- struct eh_frame_hdr_info *hdr_info;
unsigned int lo, hi, mid;
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;
-
lo = 0;
hi = sec_info->count;
mid = 0;
if (sec_info->entry[mid].removed)
return (bfd_vma) -1;
+ /* If converting personality pointers to DW_EH_PE_pcrel, there will be
+ no need for run-time relocation against the personality field. */
+ if (sec_info->entry[mid].cie
+ && sec_info->entry[mid].u.cie.make_per_encoding_relative
+ && offset == (sec_info->entry[mid].offset + 8
+ + sec_info->entry[mid].u.cie.personality_offset))
+ return (bfd_vma) -2;
+
/* 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
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;
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;
{
BFD_ASSERT (action & 1);
*aug++ = 'R';
- *buf++ = DW_EH_PE_pcrel;
+ *buf++ = make_pc_relative (DW_EH_PE_absptr, ptr_size);
action &= ~1;
}
if (action & 2)
{
BFD_ASSERT (*buf == ent->lsda_encoding);
- *buf |= DW_EH_PE_pcrel;
+ *buf = make_pc_relative (*buf, ptr_size);
action &= ~2;
}
buf++;
break;
case 'P':
+ if (ent->u.cie.make_per_encoding_relative)
+ *buf = make_pc_relative (*buf, ptr_size);
per_encoding = *buf++;
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->u.cie.per_encoding_relative);
- if ((per_encoding & 0xf0) == DW_EH_PE_aligned)
+ if ((per_encoding & 0x70) == DW_EH_PE_aligned)
buf = (contents
+ ((buf - contents + per_width - 1)
& ~((bfd_size_type) per_width - 1)));
val = read_value (abfd, buf, per_width,
get_DW_EH_PE_signed (per_encoding));
- val += ent->offset - ent->new_offset;
- val -= extra_string + extra_data;
+ if (ent->u.cie.make_per_encoding_relative)
+ val -= (sec->output_section->vma
+ + sec->output_offset
+ + (buf - contents));
+ else
+ {
+ val += (bfd_vma) ent->offset - ent->new_offset;
+ val -= extra_string + extra_data;
+ }
write_value (abfd, buf, val, per_width);
action &= ~4;
}
if (action & 1)
{
BFD_ASSERT (*buf == ent->fde_encoding);
- *buf |= DW_EH_PE_pcrel;
+ *buf = make_pc_relative (*buf, ptr_size);
action &= ~1;
}
buf++;
address = value;
if (value)
{
- switch (ent->fde_encoding & 0xf0)
+ switch (ent->fde_encoding & 0x70)
{
- case DW_EH_PE_indirect:
case DW_EH_PE_textrel:
BFD_ASSERT (hdr_info == NULL);
break;
}
break;
case DW_EH_PE_pcrel:
- value += ent->offset - ent->new_offset;
+ value += (bfd_vma) ent->offset - ent->new_offset;
address += (sec->output_section->vma
+ sec->output_offset
+ ent->offset + 8);
+ ent->new_offset);
}
- if ((ent->lsda_encoding & 0xf0) == DW_EH_PE_pcrel
+ if ((ent->lsda_encoding & 0x70) == DW_EH_PE_pcrel
|| cie->u.cie.make_lsda_relative)
{
buf += ent->lsda_offset;
get_DW_EH_PE_signed (ent->lsda_encoding));
if (value)
{
- if ((ent->lsda_encoding & 0xf0) == DW_EH_PE_pcrel)
- value += ent->offset - ent->new_offset;
+ if ((ent->lsda_encoding & 0x70) == DW_EH_PE_pcrel)
+ value += (bfd_vma) ent->offset - ent->new_offset;
else if (cie->u.cie.make_lsda_relative)
value -= (sec->output_section->vma
+ sec->output_offset
if (ent->set_loc)
{
/* Adjust DW_CFA_set_loc. */
- unsigned int cnt, width;
+ unsigned int cnt;
bfd_vma new_offset;
width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
for (cnt = 1; cnt <= ent->set_loc[0]; cnt++)
{
- bfd_vma value;
buf = start + ent->set_loc[cnt];
value = read_value (abfd, buf, width,
if (!value)
continue;
- if ((ent->fde_encoding & 0xf0) == DW_EH_PE_pcrel)
- value += ent->offset + 8 - new_offset;
+ if ((ent->fde_encoding & 0x70) == DW_EH_PE_pcrel)
+ value += (bfd_vma) ent->offset + 8 - new_offset;
if (ent->make_relative)
value -= (sec->output_section->vma
+ sec->output_offset
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);