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authorH.J. Lu <hjl.tools@gmail.com>2012-08-31 20:41:41 +0000
committerH.J. Lu <hjl.tools@gmail.com>2012-08-31 20:41:41 +0000
commitdaa67607072dd28275d2a54d6fba1623094905e8 (patch)
tree2bbe90dd3eb861e98df4643fb5b48db2b222f0da /bfd/elf64-x86-64.c
parentb192990071091aa44c292fc8c3cd6d1ae4ee8327 (diff)
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Convert mov to lea in size_dynamic_sections
bfd/ * elf32-i386.c (elf_i386_convert_mov_to_lea): New. (elf_i386_size_dynamic_sections): Use it on input sections. (elf_i386_relocate_section): Don't convert "mov foo@GOT(%reg), %reg" to "lea foo@GOTOFF(%reg), %reg" for local symbols here. * elf64-x86-64.c (elf_x86_64_convert_mov_to_lea): New. (elf_x86_64_size_dynamic_sections): Use it on input sections. (elf_x86_64_relocate_section): Don't convert "mov foo@GOTPCREL(%rip), %reg" to "lea foo@GOTOFF(%reg), %reg" for local symbols. ld/testsuite/ * ld-i386/i386.exp: Run lea1d, lea1f, lea1f. * ld-x86-64/x86-64.exp: Run lea1g, lea1h, lea1i, lea1j, lea1k, lea1l. * ld-ifunc/ifunc-13-i386.d: Remove R_386_RELATIVE entry. * ld-i386/lea1d.d: New file. * ld-i386/lea1e.d: Likewise. * ld-i386/lea1f.d: Likewise. * ld-x86-64/lea1g.d: Likewise. * ld-x86-64/lea1h.d: Likewise. * ld-x86-64/lea1i.d: Likewise. * ld-x86-64/lea1j.d: Likewise. * ld-x86-64/lea1k.d: Likewise. * ld-x86-64/lea1l.d: Likewise.
Diffstat (limited to 'bfd/elf64-x86-64.c')
-rw-r--r--bfd/elf64-x86-64.c163
1 files changed, 147 insertions, 16 deletions
diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index cc40404..0c37cd3 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -2572,6 +2572,150 @@ elf_x86_64_readonly_dynrelocs (struct elf_link_hash_entry *h,
return TRUE;
}
+/* Convert
+ mov foo@GOTPCREL(%rip), %reg
+ to
+ lea foo(%rip), %reg
+ with the local symbol, foo. */
+
+static bfd_boolean
+elf_x86_64_convert_mov_to_lea (bfd *abfd, asection *sec,
+ struct bfd_link_info *link_info)
+{
+ Elf_Internal_Shdr *symtab_hdr;
+ Elf_Internal_Rela *internal_relocs;
+ Elf_Internal_Rela *irel, *irelend;
+ bfd_byte *contents;
+ struct elf_x86_64_link_hash_table *htab;
+ bfd_boolean changed_contents;
+ bfd_boolean changed_relocs;
+ bfd_signed_vma *local_got_refcounts;
+
+ /* Don't even try to convert non-ELF outputs. */
+ if (!is_elf_hash_table (link_info->hash))
+ return FALSE;
+
+ /* Nothing to do if there are no codes or no relocations. */
+ if ((sec->flags & (SEC_CODE | SEC_RELOC)) != (SEC_CODE | SEC_RELOC)
+ || sec->reloc_count == 0)
+ return TRUE;
+
+ symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
+
+ /* Load the relocations for this section. */
+ internal_relocs = (_bfd_elf_link_read_relocs
+ (abfd, sec, NULL, (Elf_Internal_Rela *) NULL,
+ link_info->keep_memory));
+ if (internal_relocs == NULL)
+ return FALSE;
+
+ htab = elf_x86_64_hash_table (link_info);
+ changed_contents = FALSE;
+ changed_relocs = FALSE;
+ local_got_refcounts = elf_local_got_refcounts (abfd);
+
+ /* Get the section contents. */
+ if (elf_section_data (sec)->this_hdr.contents != NULL)
+ contents = elf_section_data (sec)->this_hdr.contents;
+ else
+ {
+ if (!bfd_malloc_and_get_section (abfd, sec, &contents))
+ goto error_return;
+ }
+
+ irelend = internal_relocs + sec->reloc_count;
+ for (irel = internal_relocs; irel < irelend; irel++)
+ {
+ unsigned int r_type = ELF32_R_TYPE (irel->r_info);
+ unsigned int r_symndx = htab->r_sym (irel->r_info);
+ unsigned int indx;
+ struct elf_link_hash_entry *h;
+
+ if (r_type != R_X86_64_GOTPCREL)
+ continue;
+
+ /* Get the symbol referred to by the reloc. */
+ if (r_symndx < symtab_hdr->sh_info)
+ {
+ Elf_Internal_Sym *isym;
+
+ isym = bfd_sym_from_r_symndx (&htab->sym_cache,
+ abfd, r_symndx);
+
+ /* STT_GNU_IFUNC must keep R_X86_64_GOTPCREL relocation. */
+ if (ELF_ST_TYPE (isym->st_info) != STT_GNU_IFUNC
+ && bfd_get_8 (input_bfd,
+ contents + irel->r_offset - 2) == 0x8b)
+ {
+ bfd_put_8 (output_bfd, 0x8d,
+ contents + irel->r_offset - 2);
+ irel->r_info = htab->r_info (r_symndx, R_X86_64_PC32);
+ if (local_got_refcounts != NULL
+ && local_got_refcounts[r_symndx] > 0)
+ local_got_refcounts[r_symndx] -= 1;
+ changed_contents = TRUE;
+ changed_relocs = TRUE;
+ }
+ continue;
+ }
+
+ indx = r_symndx - symtab_hdr->sh_info;
+ h = elf_sym_hashes (abfd)[indx];
+ BFD_ASSERT (h != NULL);
+
+ 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;
+
+ /* STT_GNU_IFUNC must keep R_X86_64_GOTPCREL relocation. */
+ if (h->def_regular
+ && h->type != STT_GNU_IFUNC
+ && SYMBOL_REFERENCES_LOCAL (link_info, h)
+ && bfd_get_8 (input_bfd,
+ contents + irel->r_offset - 2) == 0x8b)
+ {
+ bfd_put_8 (output_bfd, 0x8d,
+ contents + irel->r_offset - 2);
+ irel->r_info = htab->r_info (r_symndx, R_X86_64_PC32);
+ if (h->got.refcount > 0)
+ h->got.refcount -= 1;
+ changed_contents = TRUE;
+ changed_relocs = TRUE;
+ }
+ }
+
+ if (contents != NULL
+ && elf_section_data (sec)->this_hdr.contents != contents)
+ {
+ if (!changed_contents && !link_info->keep_memory)
+ free (contents);
+ else
+ {
+ /* Cache the section contents for elf_link_input_bfd. */
+ elf_section_data (sec)->this_hdr.contents = contents;
+ }
+ }
+
+ if (elf_section_data (sec)->relocs != internal_relocs)
+ {
+ if (!changed_relocs)
+ free (internal_relocs);
+ else
+ elf_section_data (sec)->relocs = internal_relocs;
+ }
+
+ return TRUE;
+
+ error_return:
+ if (contents != NULL
+ && elf_section_data (sec)->this_hdr.contents != contents)
+ free (contents);
+ if (internal_relocs != NULL
+ && elf_section_data (sec)->relocs != internal_relocs)
+ free (internal_relocs);
+ return FALSE;
+}
+
/* Set the sizes of the dynamic sections. */
static bfd_boolean
@@ -2626,6 +2770,9 @@ elf_x86_64_size_dynamic_sections (bfd *output_bfd,
{
struct elf_dyn_relocs *p;
+ if (!elf_x86_64_convert_mov_to_lea (ibfd, s, info))
+ return FALSE;
+
for (p = (struct elf_dyn_relocs *)
(elf_section_data (s)->local_dynrel);
p != NULL;
@@ -3460,22 +3607,6 @@ elf_x86_64_relocate_section (bfd *output_bfd,
if (off >= (bfd_vma) -2)
abort ();
- if (r_type == R_X86_64_GOTPCREL
- && h->def_regular
- && SYMBOL_REFERENCES_LOCAL (info, h)
- && bfd_get_8 (input_bfd,
- contents + rel->r_offset - 2) == 0x8b)
- {
- /* Convert
- mov foo@GOTPCREL(%rip), %reg
- to
- lea foo(%rip), %reg
- */
- bfd_put_8 (output_bfd, 0x8d,
- contents + rel->r_offset - 2);
- break;
- }
-
relocation = base_got->output_section->vma
+ base_got->output_offset + off;
if (r_type != R_X86_64_GOTPCREL && r_type != R_X86_64_GOTPCREL64)