summaryrefslogtreecommitdiff
path: root/bfd/elf32-i386.c
diff options
context:
space:
mode:
Diffstat (limited to 'bfd/elf32-i386.c')
-rw-r--r--bfd/elf32-i386.c265
1 files changed, 166 insertions, 99 deletions
diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c
index e4dbf9da096..8434053f2df 100644
--- a/bfd/elf32-i386.c
+++ b/bfd/elf32-i386.c
@@ -439,7 +439,7 @@ elf_i386_check_relocs (abfd, info, sec, relocs)
bfd *dynobj;
Elf_Internal_Shdr *symtab_hdr;
struct elf_link_hash_entry **sym_hashes;
- bfd_vma *local_got_offsets;
+ bfd_signed_vma *local_got_refcounts;
const Elf_Internal_Rela *rel;
const Elf_Internal_Rela *rel_end;
asection *sgot;
@@ -452,7 +452,7 @@ elf_i386_check_relocs (abfd, info, sec, relocs)
dynobj = elf_hash_table (info)->dynobj;
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
sym_hashes = elf_sym_hashes (abfd);
- local_got_offsets = elf_local_got_offsets (abfd);
+ local_got_refcounts = elf_local_got_refcounts (abfd);
sgot = NULL;
srelgot = NULL;
@@ -522,57 +522,54 @@ elf_i386_check_relocs (abfd, info, sec, relocs)
if (h != NULL)
{
- if (h->got.offset != (bfd_vma) -1)
+ if (h->got.refcount == -1)
{
- /* We have already allocated space in the .got. */
- break;
- }
- h->got.offset = sgot->_raw_size;
+ h->got.refcount = 1;
- /* Make sure this symbol is output as a dynamic symbol. */
- if (h->dynindx == -1)
- {
- if (! bfd_elf32_link_record_dynamic_symbol (info, h))
- return false;
- }
+ /* Make sure this symbol is output as a dynamic symbol. */
+ if (h->dynindx == -1)
+ {
+ if (! bfd_elf32_link_record_dynamic_symbol (info, h))
+ return false;
+ }
- srelgot->_raw_size += sizeof (Elf32_External_Rel);
+ sgot->_raw_size += 4;
+ srelgot->_raw_size += sizeof (Elf32_External_Rel);
+ }
+ else
+ h->got.refcount += 1;
}
else
{
- /* This is a global offset table entry for a local
- symbol. */
- if (local_got_offsets == NULL)
+ /* This is a global offset table entry for a local symbol. */
+ if (local_got_refcounts == NULL)
{
size_t size;
- register unsigned int i;
- size = symtab_hdr->sh_info * sizeof (bfd_vma);
- local_got_offsets = (bfd_vma *) bfd_alloc (abfd, size);
- if (local_got_offsets == NULL)
+ size = symtab_hdr->sh_info * sizeof (bfd_signed_vma);
+ local_got_refcounts = ((bfd_signed_vma *)
+ bfd_alloc (abfd, size));
+ if (local_got_refcounts == NULL)
return false;
- elf_local_got_offsets (abfd) = local_got_offsets;
- for (i = 0; i < symtab_hdr->sh_info; i++)
- local_got_offsets[i] = (bfd_vma) -1;
+ elf_local_got_refcounts (abfd) = local_got_refcounts;
+ memset (local_got_refcounts, -1, size);
}
- if (local_got_offsets[r_symndx] != (bfd_vma) -1)
+ if (local_got_refcounts[r_symndx] == -1)
{
- /* We have already allocated space in the .got. */
- break;
- }
- local_got_offsets[r_symndx] = sgot->_raw_size;
+ local_got_refcounts[r_symndx] = 1;
- if (info->shared)
- {
- /* If we are generating a shared object, we need to
- output a R_386_RELATIVE reloc so that the dynamic
- linker can adjust this GOT entry. */
- srelgot->_raw_size += sizeof (Elf32_External_Rel);
+ sgot->_raw_size += 4;
+ if (info->shared)
+ {
+ /* If we are generating a shared object, we need to
+ output a R_386_RELATIVE reloc so that the dynamic
+ linker can adjust this GOT entry. */
+ srelgot->_raw_size += sizeof (Elf32_External_Rel);
+ }
}
+ else
+ local_got_refcounts[r_symndx] += 1;
}
-
- sgot->_raw_size += 4;
-
break;
case R_386_PLT32:
@@ -588,8 +585,13 @@ elf_i386_check_relocs (abfd, info, sec, relocs)
if (h == NULL)
continue;
- h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
-
+ if (h->plt.refcount == -1)
+ {
+ h->plt.refcount = 1;
+ h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
+ }
+ else
+ h->plt.refcount += 1;
break;
case R_386_32:
@@ -766,14 +768,81 @@ elf_i386_gc_mark_hook (abfd, info, rel, h, sym)
static boolean
elf_i386_gc_sweep_hook (abfd, info, sec, relocs)
- bfd *abfd ATTRIBUTE_UNUSED;
+ bfd *abfd;
struct bfd_link_info *info ATTRIBUTE_UNUSED;
- asection *sec ATTRIBUTE_UNUSED;
- const Elf_Internal_Rela *relocs ATTRIBUTE_UNUSED;
+ asection *sec;
+ const Elf_Internal_Rela *relocs;
{
- /* ??? It would seem that the existing i386 code does no sort
- of reference counting or whatnot on its GOT and PLT entries,
- so it is not possible to garbage collect them at this time. */
+ Elf_Internal_Shdr *symtab_hdr;
+ struct elf_link_hash_entry **sym_hashes;
+ bfd_signed_vma *local_got_refcounts;
+ const Elf_Internal_Rela *rel, *relend;
+ unsigned long r_symndx;
+ struct elf_link_hash_entry *h;
+ bfd *dynobj;
+ asection *sgot;
+ asection *srelgot;
+
+ symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
+ sym_hashes = elf_sym_hashes (abfd);
+ local_got_refcounts = elf_local_got_refcounts (abfd);
+
+ dynobj = elf_hash_table (info)->dynobj;
+ if (dynobj == NULL)
+ return true;
+
+ sgot = bfd_get_section_by_name (dynobj, ".got");
+ srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
+
+ relend = relocs + sec->reloc_count;
+ for (rel = relocs; rel < relend; rel++)
+ switch (ELF32_R_TYPE (rel->r_info))
+ {
+ case R_386_GOT32:
+ case R_386_GOTOFF:
+ case R_386_GOTPC:
+ r_symndx = ELF32_R_SYM (rel->r_info);
+ if (r_symndx >= symtab_hdr->sh_info)
+ {
+ h = sym_hashes[r_symndx - symtab_hdr->sh_info];
+ if (h->got.refcount > 0)
+ {
+ h->got.refcount -= 1;
+ if (h->got.refcount == 0)
+ {
+ sgot->_raw_size -= 4;
+ srelgot->_raw_size -= sizeof (Elf32_External_Rel);
+ }
+ }
+ }
+ else if (local_got_refcounts != NULL)
+ {
+ if (local_got_refcounts[r_symndx] > 0)
+ {
+ local_got_refcounts[r_symndx] -= 1;
+ if (local_got_refcounts[r_symndx] == 0)
+ {
+ sgot->_raw_size -= 4;
+ if (info->shared)
+ srelgot->_raw_size -= sizeof (Elf32_External_Rel);
+ }
+ }
+ }
+ break;
+
+ case R_386_PLT32:
+ r_symndx = ELF32_R_SYM (rel->r_info);
+ if (r_symndx >= symtab_hdr->sh_info)
+ {
+ h = sym_hashes[r_symndx - symtab_hdr->sh_info];
+ if (h->plt.refcount > 0)
+ h->plt.refcount -= 1;
+ }
+ break;
+
+ default:
+ break;
+ }
return true;
}
@@ -812,16 +881,18 @@ elf_i386_adjust_dynamic_symbol (info, h)
if (h->type == STT_FUNC
|| (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
{
- if (! info->shared
- && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
- && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0)
+ if ((! info->shared
+ && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
+ && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0)
+ || (info->shared && h->plt.refcount <= 0))
{
/* This case can occur if we saw a PLT32 reloc in an input
- file, but the symbol was never referred to by a dynamic
- object. In such a case, we don't actually need to build
- a procedure linkage table, and we can just do a PC32
- reloc instead. */
- BFD_ASSERT ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0);
+ file, but the symbol was never referred to by a dynamic
+ object, or if all references were garbage collected. In
+ such a case, we don't actually need to build a procedure
+ linkage table, and we can just do a PC32 reloc instead. */
+ h->plt.offset = (bfd_vma) -1;
+ h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
return true;
}
@@ -859,13 +930,11 @@ elf_i386_adjust_dynamic_symbol (info, h)
/* We also need to make an entry in the .got.plt section, which
will be placed in the .got section by the linker script. */
-
s = bfd_get_section_by_name (dynobj, ".got.plt");
BFD_ASSERT (s != NULL);
s->_raw_size += 4;
/* We also need to make an entry in the .rel.plt section. */
-
s = bfd_get_section_by_name (dynobj, ".rel.plt");
BFD_ASSERT (s != NULL);
s->_raw_size += sizeof (Elf32_External_Rel);
@@ -1193,9 +1262,14 @@ elf_i386_relocate_section (output_bfd, info, input_bfd, input_section,
sym_hashes = elf_sym_hashes (input_bfd);
local_got_offsets = elf_local_got_offsets (input_bfd);
- sgot = NULL;
- splt = NULL;
sreloc = NULL;
+ splt = NULL;
+ sgot = NULL;
+ if (dynobj != NULL)
+ {
+ splt = bfd_get_section_by_name (dynobj, ".plt");
+ sgot = bfd_get_section_by_name (dynobj, ".got");
+ }
rel = relocs;
relend = relocs + input_section->reloc_count;
@@ -1273,6 +1347,7 @@ elf_i386_relocate_section (output_bfd, info, input_bfd, input_section,
sec = h->root.u.def.section;
if (r_type == R_386_GOTPC
|| (r_type == R_386_PLT32
+ && splt != NULL
&& h->plt.offset != (bfd_vma) -1)
|| (r_type == R_386_GOT32
&& elf_hash_table (info)->dynamic_sections_created
@@ -1333,11 +1408,7 @@ elf_i386_relocate_section (output_bfd, info, input_bfd, input_section,
case R_386_GOT32:
/* Relocation is to the entry for this symbol in the global
offset table. */
- if (sgot == NULL)
- {
- sgot = bfd_get_section_by_name (dynobj, ".got");
- BFD_ASSERT (sgot != NULL);
- }
+ BFD_ASSERT (sgot != NULL);
if (h != NULL)
{
@@ -1456,12 +1527,13 @@ elf_i386_relocate_section (output_bfd, info, input_bfd, input_section,
/* Relocation is to the entry for this symbol in the
procedure linkage table. */
- /* Resolve a PLT32 reloc again a local symbol directly,
+ /* Resolve a PLT32 reloc against a local symbol directly,
without using the procedure linkage table. */
if (h == NULL)
break;
- if (h->plt.offset == (bfd_vma) -1)
+ if (h->plt.offset == (bfd_vma) -1
+ || splt == NULL)
{
/* We didn't make a PLT entry for this symbol. This
happens when statically linking PIC code, or when
@@ -1469,12 +1541,6 @@ elf_i386_relocate_section (output_bfd, info, input_bfd, input_section,
break;
}
- if (splt == NULL)
- {
- splt = bfd_get_section_by_name (dynobj, ".plt");
- BFD_ASSERT (splt != NULL);
- }
-
relocation = (splt->output_section->vma
+ splt->output_offset
+ h->plt.offset);
@@ -1741,17 +1807,21 @@ elf_i386_finish_dynamic_symbol (output_bfd, info, h, sym)
+ sgot->output_offset
+ (h->got.offset &~ 1));
- /* If this is a -Bsymbolic link, and the symbol is defined
- locally, we just want to emit a RELATIVE reloc. Likewise if
- the symbol was forced to be local because of a version file.
+ /* If this is a static link, or it is a -Bsymbolic link and the
+ symbol is defined locally or was forced to be local because
+ of a version file, we just want to emit a RELATIVE reloc.
The entry in the global offset table will already have been
initialized in the relocate_section function. */
- if (info->shared
- && (info->symbolic || h->dynindx == -1)
- && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
- rel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
+ if (! elf_hash_table (info)->dynamic_sections_created
+ || (info->shared
+ && (info->symbolic || h->dynindx == -1)
+ && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
+ {
+ rel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
+ }
else
{
+ BFD_ASSERT((h->got.offset & 1) == 0);
bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + h->got.offset);
rel.r_info = ELF32_R_INFO (h->dynindx, R_386_GLOB_DAT);
}
@@ -1925,27 +1995,6 @@ elf_i386_finish_dynamic_sections (output_bfd, info)
#define ELF_ARCH bfd_arch_i386
#define ELF_MACHINE_CODE EM_386
#define ELF_MAXPAGESIZE 0x1000
-#define elf_info_to_howto elf_i386_info_to_howto
-#define elf_info_to_howto_rel elf_i386_info_to_howto_rel
-#define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup
-#define bfd_elf32_bfd_is_local_label_name \
- elf_i386_is_local_label_name
-#define elf_backend_create_dynamic_sections \
- _bfd_elf_create_dynamic_sections
-#define bfd_elf32_bfd_link_hash_table_create \
- elf_i386_link_hash_table_create
-#define elf_backend_check_relocs elf_i386_check_relocs
-#define elf_backend_adjust_dynamic_symbol \
- elf_i386_adjust_dynamic_symbol
-#define elf_backend_size_dynamic_sections \
- elf_i386_size_dynamic_sections
-#define elf_backend_relocate_section elf_i386_relocate_section
-#define elf_backend_finish_dynamic_symbol \
- elf_i386_finish_dynamic_symbol
-#define elf_backend_finish_dynamic_sections \
- elf_i386_finish_dynamic_sections
-#define elf_backend_gc_mark_hook elf_i386_gc_mark_hook
-#define elf_backend_gc_sweep_hook elf_i386_gc_sweep_hook
#define elf_backend_can_gc_sections 1
#define elf_backend_want_got_plt 1
@@ -1954,4 +2003,22 @@ elf_i386_finish_dynamic_sections (output_bfd, info)
#define elf_backend_got_header_size 12
#define elf_backend_plt_header_size PLT_ENTRY_SIZE
+#define elf_info_to_howto elf_i386_info_to_howto
+#define elf_info_to_howto_rel elf_i386_info_to_howto_rel
+
+#define bfd_elf32_bfd_final_link _bfd_elf32_gc_common_final_link
+#define bfd_elf32_bfd_is_local_label_name elf_i386_is_local_label_name
+#define bfd_elf32_bfd_link_hash_table_create elf_i386_link_hash_table_create
+#define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup
+
+#define elf_backend_adjust_dynamic_symbol elf_i386_adjust_dynamic_symbol
+#define elf_backend_check_relocs elf_i386_check_relocs
+#define elf_backend_create_dynamic_sections _bfd_elf_create_dynamic_sections
+#define elf_backend_finish_dynamic_sections elf_i386_finish_dynamic_sections
+#define elf_backend_finish_dynamic_symbol elf_i386_finish_dynamic_symbol
+#define elf_backend_gc_mark_hook elf_i386_gc_mark_hook
+#define elf_backend_gc_sweep_hook elf_i386_gc_sweep_hook
+#define elf_backend_relocate_section elf_i386_relocate_section
+#define elf_backend_size_dynamic_sections elf_i386_size_dynamic_sections
+
#include "elf32-target.h"