mirror of
https://github.com/espressif/binutils-gdb.git
synced 2025-06-26 22:07:58 +08:00
Extract convert_load_reloc from x86 convert_load
* elf32-i386.c (elf_i386_convert_load): Extract the GOT load conversion to ... (elf_i386_convert_load_reloc): This. New function. * elf64-x86-64.c (elf_x86_64_convert_load): Extract the GOT load conversion to ... (elf_x86_64_convert_load_reloc): This. New function.
This commit is contained in:
H.J. Lu
@ -1,3 +1,12 @@
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2016-05-05 H.J. Lu <hongjiu.lu@intel.com>
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* elf32-i386.c (elf_i386_convert_load): Extract the GOT load
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conversion to ...
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(elf_i386_convert_load_reloc): This. New function.
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* elf64-x86-64.c (elf_x86_64_convert_load): Extract the GOT load
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conversion to ...
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(elf_x86_64_convert_load_reloc): This. New function.
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2016-05-05 H.J. Lu <hongjiu.lu@intel.com>
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2016-05-05 H.J. Lu <hongjiu.lu@intel.com>
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* elf32-i386.c (elf_i386_check_tls_transition): Remove abfd.
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* elf32-i386.c (elf_i386_check_tls_transition): Remove abfd.
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566
bfd/elf32-i386.c
566
bfd/elf32-i386.c
@ -1499,6 +1499,255 @@ elf_i386_tls_transition (struct bfd_link_info *info, bfd *abfd,
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return TRUE;
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return TRUE;
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}
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}
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/* With the local symbol, foo, we convert
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mov foo@GOT[(%reg1)], %reg2
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to
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lea foo[@GOTOFF(%reg1)], %reg2
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and convert
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call/jmp *foo@GOT[(%reg)]
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to
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nop call foo/jmp foo nop
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When PIC is false, convert
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test %reg1, foo@GOT[(%reg2)]
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to
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test $foo, %reg1
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and convert
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binop foo@GOT[(%reg1)], %reg2
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to
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binop $foo, %reg2
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where binop is one of adc, add, and, cmp, or, sbb, sub, xor
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instructions. */
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static
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bfd_boolean
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elf_i386_convert_load_reloc (bfd *abfd, Elf_Internal_Shdr *symtab_hdr,
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bfd_byte *contents,
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Elf_Internal_Rela *irel,
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struct elf_link_hash_entry *h,
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bfd_boolean *converted,
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struct bfd_link_info *link_info)
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{
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struct elf_i386_link_hash_table *htab;
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unsigned int opcode;
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unsigned int modrm;
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bfd_boolean baseless;
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Elf_Internal_Sym *isym;
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unsigned int addend;
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unsigned int nop;
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bfd_vma nop_offset;
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bfd_boolean is_pic;
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bfd_boolean to_reloc_32;
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unsigned int r_type;
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unsigned int r_symndx;
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bfd_vma roff = irel->r_offset;
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if (roff < 2)
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return TRUE;
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/* Addend for R_386_GOT32 and R_386_GOT32X relocations must be 0. */
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addend = bfd_get_32 (abfd, contents + roff);
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if (addend != 0)
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return TRUE;
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htab = elf_i386_hash_table (link_info);
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is_pic = bfd_link_pic (link_info);
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r_type = ELF32_R_TYPE (irel->r_info);
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r_symndx = ELF32_R_SYM (irel->r_info);
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modrm = bfd_get_8 (abfd, contents + roff - 1);
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baseless = (modrm & 0xc7) == 0x5;
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if (r_type == R_386_GOT32X && baseless && is_pic)
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{
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/* For PIC, disallow R_386_GOT32X without a base register
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since we don't know what the GOT base is. Allow
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R_386_GOT32 for existing object files. */
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const char *name;
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if (h == NULL)
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{
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isym = bfd_sym_from_r_symndx (&htab->sym_cache, abfd,
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r_symndx);
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name = bfd_elf_sym_name (abfd, symtab_hdr, isym, NULL);
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}
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else
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name = h->root.root.string;
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(*_bfd_error_handler)
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(_("%B: direct GOT relocation R_386_GOT32X against `%s' without base register can not be used when making a shared object"),
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abfd, name);
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return FALSE;
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}
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opcode = bfd_get_8 (abfd, contents + roff - 2);
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/* Convert mov to lea since it has been done for a while. */
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if (opcode != 0x8b)
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{
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/* Only convert R_386_GOT32X relocation for call, jmp or
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one of adc, add, and, cmp, or, sbb, sub, test, xor
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instructions. */
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if (r_type != R_386_GOT32X)
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return TRUE;
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}
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/* Convert to R_386_32 if PIC is false or there is no base
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register. */
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to_reloc_32 = !is_pic || baseless;
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/* Try to convert R_386_GOT32 and R_386_GOT32X. Get the symbol
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referred to by the reloc. */
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if (h == NULL)
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{
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if (opcode == 0x0ff)
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/* Convert "call/jmp *foo@GOT[(%reg)]". */
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goto convert_branch;
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else
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/* Convert "mov foo@GOT[(%reg1)], %reg2",
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"test %reg1, foo@GOT(%reg2)" and
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"binop foo@GOT[(%reg1)], %reg2". */
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goto convert_load;
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}
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/* Undefined weak symbol is only bound locally in executable
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and its reference is resolved as 0. */
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if (UNDEFINED_WEAK_RESOLVED_TO_ZERO (link_info, TRUE,
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elf_i386_hash_entry (h)))
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{
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if (opcode == 0xff)
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{
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/* No direct branch to 0 for PIC. */
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if (is_pic)
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return TRUE;
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else
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goto convert_branch;
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}
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else
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{
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/* We can convert load of address 0 to R_386_32. */
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to_reloc_32 = TRUE;
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goto convert_load;
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}
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}
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if (opcode == 0xff)
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{
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/* We have "call/jmp *foo@GOT[(%reg)]". */
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if ((h->root.type == bfd_link_hash_defined
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|| h->root.type == bfd_link_hash_defweak)
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&& SYMBOL_REFERENCES_LOCAL (link_info, h))
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{
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/* The function is locally defined. */
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convert_branch:
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/* Convert R_386_GOT32X to R_386_PC32. */
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if (modrm == 0x15 || (modrm & 0xf8) == 0x90)
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{
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/* Convert to "nop call foo". ADDR_PREFIX_OPCODE
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is a nop prefix. */
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modrm = 0xe8;
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nop = link_info->call_nop_byte;
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if (link_info->call_nop_as_suffix)
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{
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nop_offset = roff + 3;
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irel->r_offset -= 1;
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}
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else
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nop_offset = roff - 2;
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}
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else
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{
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/* Convert to "jmp foo nop". */
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modrm = 0xe9;
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nop = NOP_OPCODE;
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nop_offset = roff + 3;
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irel->r_offset -= 1;
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}
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bfd_put_8 (abfd, nop, contents + nop_offset);
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bfd_put_8 (abfd, modrm, contents + irel->r_offset - 1);
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/* When converting to PC-relative relocation, we
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need to adjust addend by -4. */
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bfd_put_32 (abfd, -4, contents + irel->r_offset);
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irel->r_info = ELF32_R_INFO (r_symndx, R_386_PC32);
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*converted = TRUE;
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}
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}
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else
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{
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/* We have "mov foo@GOT[(%re1g)], %reg2",
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"test %reg1, foo@GOT(%reg2)" and
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"binop foo@GOT[(%reg1)], %reg2".
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Avoid optimizing _DYNAMIC since ld.so may use its
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link-time address. */
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if (h == htab->elf.hdynamic)
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return TRUE;
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/* def_regular is set by an assignment in a linker script in
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bfd_elf_record_link_assignment. */
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if ((h->def_regular
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|| h->root.type == bfd_link_hash_defined
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|| h->root.type == bfd_link_hash_defweak)
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&& SYMBOL_REFERENCES_LOCAL (link_info, h))
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{
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convert_load:
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if (opcode == 0x8b)
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{
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if (to_reloc_32)
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{
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/* Convert "mov foo@GOT[(%reg1)], %reg2" to
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"mov $foo, %reg2" with R_386_32. */
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r_type = R_386_32;
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modrm = 0xc0 | (modrm & 0x38) >> 3;
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bfd_put_8 (abfd, modrm, contents + roff - 1);
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opcode = 0xc7;
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}
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else
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{
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/* Convert "mov foo@GOT(%reg1), %reg2" to
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"lea foo@GOTOFF(%reg1), %reg2". */
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r_type = R_386_GOTOFF;
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opcode = 0x8d;
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}
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}
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else
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{
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/* Only R_386_32 is supported. */
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if (!to_reloc_32)
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return TRUE;
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if (opcode == 0x85)
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|
{
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|
/* Convert "test %reg1, foo@GOT(%reg2)" to
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|
"test $foo, %reg1". */
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|
modrm = 0xc0 | (modrm & 0x38) >> 3;
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|
opcode = 0xf7;
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|
}
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|
else
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|
{
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|
/* Convert "binop foo@GOT(%reg1), %reg2" to
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|
"binop $foo, %reg2". */
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|
modrm = (0xc0
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|
| (modrm & 0x38) >> 3
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|
| (opcode & 0x3c));
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|
opcode = 0x81;
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||||||
|
}
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|
bfd_put_8 (abfd, modrm, contents + roff - 1);
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|
r_type = R_386_32;
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|
}
|
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|
|
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|
bfd_put_8 (abfd, opcode, contents + roff - 2);
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|
irel->r_info = ELF32_R_INFO (r_symndx, r_type);
|
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|
|
||||||
|
*converted = TRUE;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
return TRUE;
|
||||||
|
}
|
||||||
|
|
||||||
/* Rename some of the generic section flags to better document how they
|
/* Rename some of the generic section flags to better document how they
|
||||||
are used here. */
|
are used here. */
|
||||||
#define need_convert_load sec_flg0
|
#define need_convert_load sec_flg0
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@ -2718,37 +2967,18 @@ elf_i386_readonly_dynrelocs (struct elf_link_hash_entry *h, void *inf)
|
|||||||
return TRUE;
|
return TRUE;
|
||||||
}
|
}
|
||||||
|
|
||||||
/* With the local symbol, foo, we convert
|
/* Convert load via the GOT slot to load immediate. */
|
||||||
mov foo@GOT[(%reg1)], %reg2
|
|
||||||
to
|
|
||||||
lea foo[@GOTOFF(%reg1)], %reg2
|
|
||||||
and convert
|
|
||||||
call/jmp *foo@GOT[(%reg)]
|
|
||||||
to
|
|
||||||
nop call foo/jmp foo nop
|
|
||||||
When PIC is false, convert
|
|
||||||
test %reg1, foo@GOT[(%reg2)]
|
|
||||||
to
|
|
||||||
test $foo, %reg1
|
|
||||||
and convert
|
|
||||||
binop foo@GOT[(%reg1)], %reg2
|
|
||||||
to
|
|
||||||
binop $foo, %reg2
|
|
||||||
where binop is one of adc, add, and, cmp, or, sbb, sub, xor
|
|
||||||
instructions. */
|
|
||||||
|
|
||||||
static bfd_boolean
|
static bfd_boolean
|
||||||
elf_i386_convert_load (bfd *abfd, asection *sec,
|
elf_i386_convert_load (bfd *abfd, asection *sec,
|
||||||
struct bfd_link_info *link_info)
|
struct bfd_link_info *link_info)
|
||||||
{
|
{
|
||||||
|
struct elf_i386_link_hash_table *htab;
|
||||||
Elf_Internal_Shdr *symtab_hdr;
|
Elf_Internal_Shdr *symtab_hdr;
|
||||||
Elf_Internal_Rela *internal_relocs;
|
Elf_Internal_Rela *internal_relocs;
|
||||||
Elf_Internal_Rela *irel, *irelend;
|
Elf_Internal_Rela *irel, *irelend;
|
||||||
bfd_byte *contents;
|
bfd_byte *contents;
|
||||||
struct elf_i386_link_hash_table *htab;
|
bfd_boolean changed;
|
||||||
bfd_boolean changed_contents;
|
|
||||||
bfd_boolean changed_relocs;
|
|
||||||
bfd_boolean is_pic;
|
|
||||||
bfd_signed_vma *local_got_refcounts;
|
bfd_signed_vma *local_got_refcounts;
|
||||||
|
|
||||||
/* Don't even try to convert non-ELF outputs. */
|
/* Don't even try to convert non-ELF outputs. */
|
||||||
@ -2770,13 +3000,10 @@ elf_i386_convert_load (bfd *abfd, asection *sec,
|
|||||||
if (internal_relocs == NULL)
|
if (internal_relocs == NULL)
|
||||||
return FALSE;
|
return FALSE;
|
||||||
|
|
||||||
|
changed = FALSE;
|
||||||
htab = elf_i386_hash_table (link_info);
|
htab = elf_i386_hash_table (link_info);
|
||||||
changed_contents = FALSE;
|
|
||||||
changed_relocs = FALSE;
|
|
||||||
local_got_refcounts = elf_local_got_refcounts (abfd);
|
local_got_refcounts = elf_local_got_refcounts (abfd);
|
||||||
|
|
||||||
is_pic = bfd_link_pic (link_info);
|
|
||||||
|
|
||||||
/* Get the section contents. */
|
/* Get the section contents. */
|
||||||
if (elf_section_data (sec)->this_hdr.contents != NULL)
|
if (elf_section_data (sec)->this_hdr.contents != NULL)
|
||||||
contents = elf_section_data (sec)->this_hdr.contents;
|
contents = elf_section_data (sec)->this_hdr.contents;
|
||||||
@ -2790,269 +3017,48 @@ elf_i386_convert_load (bfd *abfd, asection *sec,
|
|||||||
for (irel = internal_relocs; irel < irelend; irel++)
|
for (irel = internal_relocs; irel < irelend; irel++)
|
||||||
{
|
{
|
||||||
unsigned int r_type = ELF32_R_TYPE (irel->r_info);
|
unsigned int r_type = ELF32_R_TYPE (irel->r_info);
|
||||||
unsigned int r_symndx = ELF32_R_SYM (irel->r_info);
|
unsigned int r_symndx;
|
||||||
unsigned int indx;
|
|
||||||
struct elf_link_hash_entry *h;
|
struct elf_link_hash_entry *h;
|
||||||
unsigned int opcode;
|
bfd_boolean converted;
|
||||||
unsigned int modrm;
|
|
||||||
bfd_vma roff;
|
|
||||||
bfd_boolean baseless;
|
|
||||||
Elf_Internal_Sym *isym;
|
|
||||||
unsigned int addend;
|
|
||||||
unsigned int nop;
|
|
||||||
bfd_vma nop_offset;
|
|
||||||
bfd_boolean to_reloc_32;
|
|
||||||
|
|
||||||
if (r_type != R_386_GOT32 && r_type != R_386_GOT32X)
|
if (r_type != R_386_GOT32 && r_type != R_386_GOT32X)
|
||||||
continue;
|
continue;
|
||||||
|
|
||||||
roff = irel->r_offset;
|
r_symndx = ELF32_R_SYM (irel->r_info);
|
||||||
if (roff < 2)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
/* Addend for R_386_GOT32 and R_386_GOT32X relocations must be 0. */
|
|
||||||
addend = bfd_get_32 (abfd, contents + roff);
|
|
||||||
if (addend != 0)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
modrm = bfd_get_8 (abfd, contents + roff - 1);
|
|
||||||
baseless = (modrm & 0xc7) == 0x5;
|
|
||||||
|
|
||||||
if (r_type == R_386_GOT32X && baseless && is_pic)
|
|
||||||
{
|
|
||||||
/* For PIC, disallow R_386_GOT32X without a base register
|
|
||||||
since we don't know what the GOT base is. Allow
|
|
||||||
R_386_GOT32 for existing object files. */
|
|
||||||
const char *name;
|
|
||||||
|
|
||||||
if (r_symndx < symtab_hdr->sh_info)
|
|
||||||
{
|
|
||||||
isym = bfd_sym_from_r_symndx (&htab->sym_cache, abfd,
|
|
||||||
r_symndx);
|
|
||||||
name = bfd_elf_sym_name (abfd, symtab_hdr, isym, NULL);
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
indx = r_symndx - symtab_hdr->sh_info;
|
|
||||||
h = elf_sym_hashes (abfd)[indx];
|
|
||||||
BFD_ASSERT (h != NULL);
|
|
||||||
name = h->root.root.string;
|
|
||||||
}
|
|
||||||
|
|
||||||
(*_bfd_error_handler)
|
|
||||||
(_("%B: direct GOT relocation R_386_GOT32X against `%s' without base register can not be used when making a shared object"),
|
|
||||||
abfd, name);
|
|
||||||
goto error_return;
|
|
||||||
}
|
|
||||||
|
|
||||||
opcode = bfd_get_8 (abfd, contents + roff - 2);
|
|
||||||
|
|
||||||
/* Convert mov to lea since it has been done for a while. */
|
|
||||||
if (opcode != 0x8b)
|
|
||||||
{
|
|
||||||
/* Only convert R_386_GOT32X relocation for call, jmp or
|
|
||||||
one of adc, add, and, cmp, or, sbb, sub, test, xor
|
|
||||||
instructions. */
|
|
||||||
if (r_type != R_386_GOT32X)
|
|
||||||
continue;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Convert to R_386_32 if PIC is false or there is no base
|
|
||||||
register. */
|
|
||||||
to_reloc_32 = !is_pic || baseless;
|
|
||||||
|
|
||||||
/* Try to convert R_386_GOT32 and R_386_GOT32X. Get the symbol
|
|
||||||
referred to by the reloc. */
|
|
||||||
if (r_symndx < symtab_hdr->sh_info)
|
if (r_symndx < symtab_hdr->sh_info)
|
||||||
{
|
h = elf_i386_get_local_sym_hash (htab, sec->owner,
|
||||||
isym = bfd_sym_from_r_symndx (&htab->sym_cache,
|
(const Elf_Internal_Rela *) irel,
|
||||||
abfd, r_symndx);
|
FALSE);
|
||||||
|
|
||||||
/* STT_GNU_IFUNC must keep GOT32 relocations. */
|
|
||||||
if (ELF_ST_TYPE (isym->st_info) == STT_GNU_IFUNC)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
h = NULL;
|
|
||||||
if (opcode == 0x0ff)
|
|
||||||
/* Convert "call/jmp *foo@GOT[(%reg)]". */
|
|
||||||
goto convert_branch;
|
|
||||||
else
|
|
||||||
/* Convert "mov foo@GOT[(%reg1)], %reg2",
|
|
||||||
"test %reg1, foo@GOT(%reg2)" and
|
|
||||||
"binop foo@GOT[(%reg1)], %reg2". */
|
|
||||||
goto convert_load;
|
|
||||||
}
|
|
||||||
|
|
||||||
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 GOT32 relocations. */
|
|
||||||
if (h->type == STT_GNU_IFUNC)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
/* Undefined weak symbol is only bound locally in executable
|
|
||||||
and its reference is resolved as 0. */
|
|
||||||
if (UNDEFINED_WEAK_RESOLVED_TO_ZERO (link_info, TRUE,
|
|
||||||
elf_i386_hash_entry (h)))
|
|
||||||
{
|
|
||||||
if (opcode == 0xff)
|
|
||||||
{
|
|
||||||
/* No direct branch to 0 for PIC. */
|
|
||||||
if (is_pic)
|
|
||||||
continue;
|
|
||||||
else
|
|
||||||
goto convert_branch;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* We can convert load of address 0 to R_386_32. */
|
|
||||||
to_reloc_32 = TRUE;
|
|
||||||
goto convert_load;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
if (opcode == 0xff)
|
|
||||||
{
|
|
||||||
/* We have "call/jmp *foo@GOT[(%reg)]". */
|
|
||||||
if ((h->root.type == bfd_link_hash_defined
|
|
||||||
|| h->root.type == bfd_link_hash_defweak)
|
|
||||||
&& SYMBOL_REFERENCES_LOCAL (link_info, h))
|
|
||||||
{
|
|
||||||
/* The function is locally defined. */
|
|
||||||
convert_branch:
|
|
||||||
/* Convert R_386_GOT32X to R_386_PC32. */
|
|
||||||
if (modrm == 0x15 || (modrm & 0xf8) == 0x90)
|
|
||||||
{
|
|
||||||
/* Convert to "nop call foo". ADDR_PREFIX_OPCODE
|
|
||||||
is a nop prefix. */
|
|
||||||
modrm = 0xe8;
|
|
||||||
nop = link_info->call_nop_byte;
|
|
||||||
if (link_info->call_nop_as_suffix)
|
|
||||||
{
|
|
||||||
nop_offset = roff + 3;
|
|
||||||
irel->r_offset -= 1;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
nop_offset = roff - 2;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* Convert to "jmp foo nop". */
|
|
||||||
modrm = 0xe9;
|
|
||||||
nop = NOP_OPCODE;
|
|
||||||
nop_offset = roff + 3;
|
|
||||||
irel->r_offset -= 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
bfd_put_8 (abfd, nop, contents + nop_offset);
|
|
||||||
bfd_put_8 (abfd, modrm, contents + irel->r_offset - 1);
|
|
||||||
/* When converting to PC-relative relocation, we
|
|
||||||
need to adjust addend by -4. */
|
|
||||||
bfd_put_32 (abfd, -4, contents + irel->r_offset);
|
|
||||||
irel->r_info = ELF32_R_INFO (r_symndx, R_386_PC32);
|
|
||||||
|
|
||||||
if (h)
|
|
||||||
{
|
|
||||||
if (h->got.refcount > 0)
|
|
||||||
h->got.refcount -= 1;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
if (local_got_refcounts != NULL
|
|
||||||
&& local_got_refcounts[r_symndx] > 0)
|
|
||||||
local_got_refcounts[r_symndx] -= 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
changed_contents = TRUE;
|
|
||||||
changed_relocs = TRUE;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
else
|
else
|
||||||
{
|
{
|
||||||
/* We have "mov foo@GOT[(%re1g)], %reg2",
|
h = elf_sym_hashes (abfd)[r_symndx - symtab_hdr->sh_info];
|
||||||
"test %reg1, foo@GOT(%reg2)" and
|
while (h->root.type == bfd_link_hash_indirect
|
||||||
"binop foo@GOT[(%reg1)], %reg2".
|
|| h->root.type == bfd_link_hash_warning)
|
||||||
|
h = (struct elf_link_hash_entry *) h->root.u.i.link;
|
||||||
|
}
|
||||||
|
|
||||||
Avoid optimizing _DYNAMIC since ld.so may use its
|
/* STT_GNU_IFUNC must keep GOT32 relocations. */
|
||||||
link-time address. */
|
if (h != NULL && h->type == STT_GNU_IFUNC)
|
||||||
if (h == htab->elf.hdynamic)
|
continue;
|
||||||
continue;
|
|
||||||
|
|
||||||
/* def_regular is set by an assignment in a linker script in
|
converted = FALSE;
|
||||||
bfd_elf_record_link_assignment. */
|
if (!elf_i386_convert_load_reloc (abfd, symtab_hdr, contents,
|
||||||
if ((h->def_regular
|
irel, h, &converted, link_info))
|
||||||
|| h->root.type == bfd_link_hash_defined
|
goto error_return;
|
||||||
|| h->root.type == bfd_link_hash_defweak)
|
|
||||||
&& SYMBOL_REFERENCES_LOCAL (link_info, h))
|
if (converted)
|
||||||
|
{
|
||||||
|
changed = converted;
|
||||||
|
if (h)
|
||||||
{
|
{
|
||||||
convert_load:
|
if (h->got.refcount > 0)
|
||||||
if (opcode == 0x8b)
|
h->got.refcount -= 1;
|
||||||
{
|
}
|
||||||
if (to_reloc_32)
|
else
|
||||||
{
|
{
|
||||||
/* Convert "mov foo@GOT[(%reg1)], %reg2" to
|
if (local_got_refcounts != NULL
|
||||||
"mov $foo, %reg2" with R_386_32. */
|
&& local_got_refcounts[r_symndx] > 0)
|
||||||
r_type = R_386_32;
|
local_got_refcounts[r_symndx] -= 1;
|
||||||
modrm = 0xc0 | (modrm & 0x38) >> 3;
|
|
||||||
bfd_put_8 (abfd, modrm, contents + roff - 1);
|
|
||||||
opcode = 0xc7;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* Convert "mov foo@GOT(%reg1), %reg2" to
|
|
||||||
"lea foo@GOTOFF(%reg1), %reg2". */
|
|
||||||
r_type = R_386_GOTOFF;
|
|
||||||
opcode = 0x8d;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* Only R_386_32 is supported. */
|
|
||||||
if (!to_reloc_32)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
if (opcode == 0x85)
|
|
||||||
{
|
|
||||||
/* Convert "test %reg1, foo@GOT(%reg2)" to
|
|
||||||
"test $foo, %reg1". */
|
|
||||||
modrm = 0xc0 | (modrm & 0x38) >> 3;
|
|
||||||
opcode = 0xf7;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* Convert "binop foo@GOT(%reg1), %reg2" to
|
|
||||||
"binop $foo, %reg2". */
|
|
||||||
modrm = (0xc0
|
|
||||||
| (modrm & 0x38) >> 3
|
|
||||||
| (opcode & 0x3c));
|
|
||||||
opcode = 0x81;
|
|
||||||
}
|
|
||||||
bfd_put_8 (abfd, modrm, contents + roff - 1);
|
|
||||||
r_type = R_386_32;
|
|
||||||
}
|
|
||||||
|
|
||||||
bfd_put_8 (abfd, opcode, contents + roff - 2);
|
|
||||||
irel->r_info = ELF32_R_INFO (r_symndx, r_type);
|
|
||||||
|
|
||||||
if (h)
|
|
||||||
{
|
|
||||||
if (h->got.refcount > 0)
|
|
||||||
h->got.refcount -= 1;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
if (local_got_refcounts != NULL
|
|
||||||
&& local_got_refcounts[r_symndx] > 0)
|
|
||||||
local_got_refcounts[r_symndx] -= 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
changed_contents = TRUE;
|
|
||||||
changed_relocs = TRUE;
|
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
@ -3060,7 +3066,7 @@ convert_load:
|
|||||||
if (contents != NULL
|
if (contents != NULL
|
||||||
&& elf_section_data (sec)->this_hdr.contents != contents)
|
&& elf_section_data (sec)->this_hdr.contents != contents)
|
||||||
{
|
{
|
||||||
if (!changed_contents && !link_info->keep_memory)
|
if (!changed && !link_info->keep_memory)
|
||||||
free (contents);
|
free (contents);
|
||||||
else
|
else
|
||||||
{
|
{
|
||||||
@ -3071,7 +3077,7 @@ convert_load:
|
|||||||
|
|
||||||
if (elf_section_data (sec)->relocs != internal_relocs)
|
if (elf_section_data (sec)->relocs != internal_relocs)
|
||||||
{
|
{
|
||||||
if (!changed_relocs)
|
if (!changed)
|
||||||
free (internal_relocs);
|
free (internal_relocs);
|
||||||
else
|
else
|
||||||
elf_section_data (sec)->relocs = internal_relocs;
|
elf_section_data (sec)->relocs = internal_relocs;
|
||||||
|
|||||||
@ -1634,6 +1634,401 @@ elf_x86_64_need_pic (bfd *input_bfd, asection *sec,
|
|||||||
return FALSE;
|
return FALSE;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
/* With the local symbol, foo, we convert
|
||||||
|
mov foo@GOTPCREL(%rip), %reg
|
||||||
|
to
|
||||||
|
lea foo(%rip), %reg
|
||||||
|
and convert
|
||||||
|
call/jmp *foo@GOTPCREL(%rip)
|
||||||
|
to
|
||||||
|
nop call foo/jmp foo nop
|
||||||
|
When PIC is false, convert
|
||||||
|
test %reg, foo@GOTPCREL(%rip)
|
||||||
|
to
|
||||||
|
test $foo, %reg
|
||||||
|
and convert
|
||||||
|
binop foo@GOTPCREL(%rip), %reg
|
||||||
|
to
|
||||||
|
binop $foo, %reg
|
||||||
|
where binop is one of adc, add, and, cmp, or, sbb, sub, xor
|
||||||
|
instructions. */
|
||||||
|
|
||||||
|
static bfd_boolean
|
||||||
|
elf_x86_64_convert_load_reloc (bfd *abfd, asection *sec,
|
||||||
|
bfd_byte *contents,
|
||||||
|
Elf_Internal_Rela *irel,
|
||||||
|
struct elf_link_hash_entry *h,
|
||||||
|
bfd_boolean *converted,
|
||||||
|
struct bfd_link_info *link_info)
|
||||||
|
{
|
||||||
|
struct elf_x86_64_link_hash_table *htab;
|
||||||
|
bfd_boolean is_pic;
|
||||||
|
bfd_boolean require_reloc_pc32;
|
||||||
|
bfd_boolean relocx;
|
||||||
|
bfd_boolean to_reloc_pc32;
|
||||||
|
asection *tsec;
|
||||||
|
char symtype;
|
||||||
|
bfd_signed_vma raddend;
|
||||||
|
unsigned int opcode;
|
||||||
|
unsigned int modrm;
|
||||||
|
unsigned int r_type = ELF32_R_TYPE (irel->r_info);
|
||||||
|
unsigned int r_symndx;
|
||||||
|
bfd_vma toff;
|
||||||
|
bfd_vma roff = irel->r_offset;
|
||||||
|
|
||||||
|
if (roff < (r_type == R_X86_64_REX_GOTPCRELX ? 3 : 2))
|
||||||
|
return TRUE;
|
||||||
|
|
||||||
|
raddend = irel->r_addend;
|
||||||
|
/* Addend for 32-bit PC-relative relocation must be -4. */
|
||||||
|
if (raddend != -4)
|
||||||
|
return TRUE;
|
||||||
|
|
||||||
|
htab = elf_x86_64_hash_table (link_info);
|
||||||
|
is_pic = bfd_link_pic (link_info);
|
||||||
|
|
||||||
|
relocx = (r_type == R_X86_64_GOTPCRELX
|
||||||
|
|| r_type == R_X86_64_REX_GOTPCRELX);
|
||||||
|
|
||||||
|
/* TRUE if we can convert only to R_X86_64_PC32. Enable it for
|
||||||
|
--no-relax. */
|
||||||
|
require_reloc_pc32
|
||||||
|
= link_info->disable_target_specific_optimizations > 1;
|
||||||
|
|
||||||
|
r_symndx = htab->r_sym (irel->r_info);
|
||||||
|
|
||||||
|
opcode = bfd_get_8 (abfd, contents + roff - 2);
|
||||||
|
|
||||||
|
/* Convert mov to lea since it has been done for a while. */
|
||||||
|
if (opcode != 0x8b)
|
||||||
|
{
|
||||||
|
/* Only convert R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX
|
||||||
|
for call, jmp or one of adc, add, and, cmp, or, sbb, sub,
|
||||||
|
test, xor instructions. */
|
||||||
|
if (!relocx)
|
||||||
|
return TRUE;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* We convert only to R_X86_64_PC32:
|
||||||
|
1. Branch.
|
||||||
|
2. R_X86_64_GOTPCREL since we can't modify REX byte.
|
||||||
|
3. require_reloc_pc32 is true.
|
||||||
|
4. PIC.
|
||||||
|
*/
|
||||||
|
to_reloc_pc32 = (opcode == 0xff
|
||||||
|
|| !relocx
|
||||||
|
|| require_reloc_pc32
|
||||||
|
|| is_pic);
|
||||||
|
|
||||||
|
/* Get the symbol referred to by the reloc. */
|
||||||
|
if (h == NULL)
|
||||||
|
{
|
||||||
|
Elf_Internal_Sym *isym
|
||||||
|
= bfd_sym_from_r_symndx (&htab->sym_cache, abfd, r_symndx);
|
||||||
|
|
||||||
|
/* Skip relocation against undefined symbols. */
|
||||||
|
if (isym->st_shndx == SHN_UNDEF)
|
||||||
|
return TRUE;
|
||||||
|
|
||||||
|
symtype = ELF_ST_TYPE (isym->st_info);
|
||||||
|
|
||||||
|
if (isym->st_shndx == SHN_ABS)
|
||||||
|
tsec = bfd_abs_section_ptr;
|
||||||
|
else if (isym->st_shndx == SHN_COMMON)
|
||||||
|
tsec = bfd_com_section_ptr;
|
||||||
|
else if (isym->st_shndx == SHN_X86_64_LCOMMON)
|
||||||
|
tsec = &_bfd_elf_large_com_section;
|
||||||
|
else
|
||||||
|
tsec = bfd_section_from_elf_index (abfd, isym->st_shndx);
|
||||||
|
|
||||||
|
toff = isym->st_value;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
/* Undefined weak symbol is only bound locally in executable
|
||||||
|
and its reference is resolved as 0 without relocation
|
||||||
|
overflow. We can only perform this optimization for
|
||||||
|
GOTPCRELX relocations since we need to modify REX byte.
|
||||||
|
It is OK convert mov with R_X86_64_GOTPCREL to
|
||||||
|
R_X86_64_PC32. */
|
||||||
|
if ((relocx || opcode == 0x8b)
|
||||||
|
&& UNDEFINED_WEAK_RESOLVED_TO_ZERO (link_info,
|
||||||
|
TRUE,
|
||||||
|
elf_x86_64_hash_entry (h)))
|
||||||
|
{
|
||||||
|
if (opcode == 0xff)
|
||||||
|
{
|
||||||
|
/* Skip for branch instructions since R_X86_64_PC32
|
||||||
|
may overflow. */
|
||||||
|
if (require_reloc_pc32)
|
||||||
|
return TRUE;
|
||||||
|
}
|
||||||
|
else if (relocx)
|
||||||
|
{
|
||||||
|
/* For non-branch instructions, we can convert to
|
||||||
|
R_X86_64_32/R_X86_64_32S since we know if there
|
||||||
|
is a REX byte. */
|
||||||
|
to_reloc_pc32 = FALSE;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Since we don't know the current PC when PIC is true,
|
||||||
|
we can't convert to R_X86_64_PC32. */
|
||||||
|
if (to_reloc_pc32 && is_pic)
|
||||||
|
return TRUE;
|
||||||
|
|
||||||
|
goto convert;
|
||||||
|
}
|
||||||
|
/* Avoid optimizing GOTPCREL relocations againt _DYNAMIC since
|
||||||
|
ld.so may use its link-time address. */
|
||||||
|
else if ((h->def_regular
|
||||||
|
|| h->root.type == bfd_link_hash_defined
|
||||||
|
|| h->root.type == bfd_link_hash_defweak)
|
||||||
|
&& h != htab->elf.hdynamic
|
||||||
|
&& SYMBOL_REFERENCES_LOCAL (link_info, h))
|
||||||
|
{
|
||||||
|
/* bfd_link_hash_new or bfd_link_hash_undefined is
|
||||||
|
set by an assignment in a linker script in
|
||||||
|
bfd_elf_record_link_assignment. */
|
||||||
|
if (h->def_regular
|
||||||
|
&& (h->root.type == bfd_link_hash_new
|
||||||
|
|| h->root.type == bfd_link_hash_undefined))
|
||||||
|
{
|
||||||
|
/* Skip since R_X86_64_32/R_X86_64_32S may overflow. */
|
||||||
|
if (require_reloc_pc32)
|
||||||
|
return TRUE;
|
||||||
|
goto convert;
|
||||||
|
}
|
||||||
|
tsec = h->root.u.def.section;
|
||||||
|
toff = h->root.u.def.value;
|
||||||
|
symtype = h->type;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
return TRUE;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* We can only estimate relocation overflow for R_X86_64_PC32. */
|
||||||
|
if (!to_reloc_pc32)
|
||||||
|
goto convert;
|
||||||
|
|
||||||
|
if (tsec->sec_info_type == SEC_INFO_TYPE_MERGE)
|
||||||
|
{
|
||||||
|
/* At this stage in linking, no SEC_MERGE symbol has been
|
||||||
|
adjusted, so all references to such symbols need to be
|
||||||
|
passed through _bfd_merged_section_offset. (Later, in
|
||||||
|
relocate_section, all SEC_MERGE symbols *except* for
|
||||||
|
section symbols have been adjusted.)
|
||||||
|
|
||||||
|
gas may reduce relocations against symbols in SEC_MERGE
|
||||||
|
sections to a relocation against the section symbol when
|
||||||
|
the original addend was zero. When the reloc is against
|
||||||
|
a section symbol we should include the addend in the
|
||||||
|
offset passed to _bfd_merged_section_offset, since the
|
||||||
|
location of interest is the original symbol. On the
|
||||||
|
other hand, an access to "sym+addend" where "sym" is not
|
||||||
|
a section symbol should not include the addend; Such an
|
||||||
|
access is presumed to be an offset from "sym"; The
|
||||||
|
location of interest is just "sym". */
|
||||||
|
if (symtype == STT_SECTION)
|
||||||
|
toff += raddend;
|
||||||
|
|
||||||
|
toff = _bfd_merged_section_offset (abfd, &tsec,
|
||||||
|
elf_section_data (tsec)->sec_info,
|
||||||
|
toff);
|
||||||
|
|
||||||
|
if (symtype != STT_SECTION)
|
||||||
|
toff += raddend;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
toff += raddend;
|
||||||
|
|
||||||
|
/* Don't convert if R_X86_64_PC32 relocation overflows. */
|
||||||
|
if (tsec->output_section == sec->output_section)
|
||||||
|
{
|
||||||
|
if ((toff - roff + 0x80000000) > 0xffffffff)
|
||||||
|
return TRUE;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
bfd_signed_vma distance;
|
||||||
|
|
||||||
|
/* At this point, we don't know the load addresses of TSEC
|
||||||
|
section nor SEC section. We estimate the distrance between
|
||||||
|
SEC and TSEC. We store the estimated distances in the
|
||||||
|
compressed_size field of the output section, which is only
|
||||||
|
used to decompress the compressed input section. */
|
||||||
|
if (sec->output_section->compressed_size == 0)
|
||||||
|
{
|
||||||
|
asection *asect;
|
||||||
|
bfd_size_type size = 0;
|
||||||
|
for (asect = link_info->output_bfd->sections;
|
||||||
|
asect != NULL;
|
||||||
|
asect = asect->next)
|
||||||
|
/* Skip debug sections since compressed_size is used to
|
||||||
|
compress debug sections. */
|
||||||
|
if ((asect->flags & SEC_DEBUGGING) == 0)
|
||||||
|
{
|
||||||
|
asection *i;
|
||||||
|
for (i = asect->map_head.s;
|
||||||
|
i != NULL;
|
||||||
|
i = i->map_head.s)
|
||||||
|
{
|
||||||
|
size = align_power (size, i->alignment_power);
|
||||||
|
size += i->size;
|
||||||
|
}
|
||||||
|
asect->compressed_size = size;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Don't convert GOTPCREL relocations if TSEC isn't placed
|
||||||
|
after SEC. */
|
||||||
|
distance = (tsec->output_section->compressed_size
|
||||||
|
- sec->output_section->compressed_size);
|
||||||
|
if (distance < 0)
|
||||||
|
return TRUE;
|
||||||
|
|
||||||
|
/* Take PT_GNU_RELRO segment into account by adding
|
||||||
|
maxpagesize. */
|
||||||
|
if ((toff + distance + get_elf_backend_data (abfd)->maxpagesize
|
||||||
|
- roff + 0x80000000) > 0xffffffff)
|
||||||
|
return TRUE;
|
||||||
|
}
|
||||||
|
|
||||||
|
convert:
|
||||||
|
if (opcode == 0xff)
|
||||||
|
{
|
||||||
|
/* We have "call/jmp *foo@GOTPCREL(%rip)". */
|
||||||
|
unsigned int nop;
|
||||||
|
unsigned int disp;
|
||||||
|
bfd_vma nop_offset;
|
||||||
|
|
||||||
|
/* Convert R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX to
|
||||||
|
R_X86_64_PC32. */
|
||||||
|
modrm = bfd_get_8 (abfd, contents + roff - 1);
|
||||||
|
if (modrm == 0x25)
|
||||||
|
{
|
||||||
|
/* Convert to "jmp foo nop". */
|
||||||
|
modrm = 0xe9;
|
||||||
|
nop = NOP_OPCODE;
|
||||||
|
nop_offset = irel->r_offset + 3;
|
||||||
|
disp = bfd_get_32 (abfd, contents + irel->r_offset);
|
||||||
|
irel->r_offset -= 1;
|
||||||
|
bfd_put_32 (abfd, disp, contents + irel->r_offset);
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
/* Convert to "nop call foo". ADDR_PREFIX_OPCODE
|
||||||
|
is a nop prefix. */
|
||||||
|
modrm = 0xe8;
|
||||||
|
nop = link_info->call_nop_byte;
|
||||||
|
if (link_info->call_nop_as_suffix)
|
||||||
|
{
|
||||||
|
nop_offset = irel->r_offset + 3;
|
||||||
|
disp = bfd_get_32 (abfd, contents + irel->r_offset);
|
||||||
|
irel->r_offset -= 1;
|
||||||
|
bfd_put_32 (abfd, disp, contents + irel->r_offset);
|
||||||
|
}
|
||||||
|
else
|
||||||
|
nop_offset = irel->r_offset - 2;
|
||||||
|
}
|
||||||
|
bfd_put_8 (abfd, nop, contents + nop_offset);
|
||||||
|
bfd_put_8 (abfd, modrm, contents + irel->r_offset - 1);
|
||||||
|
r_type = R_X86_64_PC32;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
unsigned int rex;
|
||||||
|
unsigned int rex_mask = REX_R;
|
||||||
|
|
||||||
|
if (r_type == R_X86_64_REX_GOTPCRELX)
|
||||||
|
rex = bfd_get_8 (abfd, contents + roff - 3);
|
||||||
|
else
|
||||||
|
rex = 0;
|
||||||
|
|
||||||
|
if (opcode == 0x8b)
|
||||||
|
{
|
||||||
|
if (to_reloc_pc32)
|
||||||
|
{
|
||||||
|
/* Convert "mov foo@GOTPCREL(%rip), %reg" to
|
||||||
|
"lea foo(%rip), %reg". */
|
||||||
|
opcode = 0x8d;
|
||||||
|
r_type = R_X86_64_PC32;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
/* Convert "mov foo@GOTPCREL(%rip), %reg" to
|
||||||
|
"mov $foo, %reg". */
|
||||||
|
opcode = 0xc7;
|
||||||
|
modrm = bfd_get_8 (abfd, contents + roff - 1);
|
||||||
|
modrm = 0xc0 | (modrm & 0x38) >> 3;
|
||||||
|
if ((rex & REX_W) != 0
|
||||||
|
&& ABI_64_P (link_info->output_bfd))
|
||||||
|
{
|
||||||
|
/* Keep the REX_W bit in REX byte for LP64. */
|
||||||
|
r_type = R_X86_64_32S;
|
||||||
|
goto rewrite_modrm_rex;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
/* If the REX_W bit in REX byte isn't needed,
|
||||||
|
use R_X86_64_32 and clear the W bit to avoid
|
||||||
|
sign-extend imm32 to imm64. */
|
||||||
|
r_type = R_X86_64_32;
|
||||||
|
/* Clear the W bit in REX byte. */
|
||||||
|
rex_mask |= REX_W;
|
||||||
|
goto rewrite_modrm_rex;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
/* R_X86_64_PC32 isn't supported. */
|
||||||
|
if (to_reloc_pc32)
|
||||||
|
return TRUE;
|
||||||
|
|
||||||
|
modrm = bfd_get_8 (abfd, contents + roff - 1);
|
||||||
|
if (opcode == 0x85)
|
||||||
|
{
|
||||||
|
/* Convert "test %reg, foo@GOTPCREL(%rip)" to
|
||||||
|
"test $foo, %reg". */
|
||||||
|
modrm = 0xc0 | (modrm & 0x38) >> 3;
|
||||||
|
opcode = 0xf7;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
/* Convert "binop foo@GOTPCREL(%rip), %reg" to
|
||||||
|
"binop $foo, %reg". */
|
||||||
|
modrm = 0xc0 | (modrm & 0x38) >> 3 | (opcode & 0x3c);
|
||||||
|
opcode = 0x81;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Use R_X86_64_32 with 32-bit operand to avoid relocation
|
||||||
|
overflow when sign-extending imm32 to imm64. */
|
||||||
|
r_type = (rex & REX_W) != 0 ? R_X86_64_32S : R_X86_64_32;
|
||||||
|
|
||||||
|
rewrite_modrm_rex:
|
||||||
|
bfd_put_8 (abfd, modrm, contents + roff - 1);
|
||||||
|
|
||||||
|
if (rex)
|
||||||
|
{
|
||||||
|
/* Move the R bit to the B bit in REX byte. */
|
||||||
|
rex = (rex & ~rex_mask) | (rex & REX_R) >> 2;
|
||||||
|
bfd_put_8 (abfd, rex, contents + roff - 3);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* No addend for R_X86_64_32/R_X86_64_32S relocations. */
|
||||||
|
irel->r_addend = 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
bfd_put_8 (abfd, opcode, contents + roff - 2);
|
||||||
|
}
|
||||||
|
|
||||||
|
irel->r_info = htab->r_info (r_symndx, r_type);
|
||||||
|
|
||||||
|
*converted = TRUE;
|
||||||
|
|
||||||
|
return TRUE;
|
||||||
|
}
|
||||||
|
|
||||||
/* Look through the relocs for a section during the first phase, and
|
/* Look through the relocs for a section during the first phase, and
|
||||||
calculate needed space in the global offset table, procedure
|
calculate needed space in the global offset table, procedure
|
||||||
linkage table, and dynamic reloc sections. */
|
linkage table, and dynamic reloc sections. */
|
||||||
@ -2946,24 +3341,7 @@ elf_x86_64_readonly_dynrelocs (struct elf_link_hash_entry *h,
|
|||||||
return TRUE;
|
return TRUE;
|
||||||
}
|
}
|
||||||
|
|
||||||
/* With the local symbol, foo, we convert
|
/* Convert load via the GOT slot to load immediate. */
|
||||||
mov foo@GOTPCREL(%rip), %reg
|
|
||||||
to
|
|
||||||
lea foo(%rip), %reg
|
|
||||||
and convert
|
|
||||||
call/jmp *foo@GOTPCREL(%rip)
|
|
||||||
to
|
|
||||||
nop call foo/jmp foo nop
|
|
||||||
When PIC is false, convert
|
|
||||||
test %reg, foo@GOTPCREL(%rip)
|
|
||||||
to
|
|
||||||
test $foo, %reg
|
|
||||||
and convert
|
|
||||||
binop foo@GOTPCREL(%rip), %reg
|
|
||||||
to
|
|
||||||
binop $foo, %reg
|
|
||||||
where binop is one of adc, add, and, cmp, or, sbb, sub, xor
|
|
||||||
instructions. */
|
|
||||||
|
|
||||||
static bfd_boolean
|
static bfd_boolean
|
||||||
elf_x86_64_convert_load (bfd *abfd, asection *sec,
|
elf_x86_64_convert_load (bfd *abfd, asection *sec,
|
||||||
@ -2974,12 +3352,8 @@ elf_x86_64_convert_load (bfd *abfd, asection *sec,
|
|||||||
Elf_Internal_Rela *irel, *irelend;
|
Elf_Internal_Rela *irel, *irelend;
|
||||||
bfd_byte *contents;
|
bfd_byte *contents;
|
||||||
struct elf_x86_64_link_hash_table *htab;
|
struct elf_x86_64_link_hash_table *htab;
|
||||||
bfd_boolean changed_contents;
|
bfd_boolean changed;
|
||||||
bfd_boolean changed_relocs;
|
|
||||||
bfd_signed_vma *local_got_refcounts;
|
bfd_signed_vma *local_got_refcounts;
|
||||||
bfd_vma maxpagesize;
|
|
||||||
bfd_boolean is_pic;
|
|
||||||
bfd_boolean require_reloc_pc32;
|
|
||||||
|
|
||||||
/* Don't even try to convert non-ELF outputs. */
|
/* Don't even try to convert non-ELF outputs. */
|
||||||
if (!is_elf_hash_table (link_info->hash))
|
if (!is_elf_hash_table (link_info->hash))
|
||||||
@ -3000,11 +3374,9 @@ elf_x86_64_convert_load (bfd *abfd, asection *sec,
|
|||||||
if (internal_relocs == NULL)
|
if (internal_relocs == NULL)
|
||||||
return FALSE;
|
return FALSE;
|
||||||
|
|
||||||
|
changed = FALSE;
|
||||||
htab = elf_x86_64_hash_table (link_info);
|
htab = elf_x86_64_hash_table (link_info);
|
||||||
changed_contents = FALSE;
|
|
||||||
changed_relocs = FALSE;
|
|
||||||
local_got_refcounts = elf_local_got_refcounts (abfd);
|
local_got_refcounts = elf_local_got_refcounts (abfd);
|
||||||
maxpagesize = get_elf_backend_data (abfd)->maxpagesize;
|
|
||||||
|
|
||||||
/* Get the section contents. */
|
/* Get the section contents. */
|
||||||
if (elf_section_data (sec)->this_hdr.contents != NULL)
|
if (elf_section_data (sec)->this_hdr.contents != NULL)
|
||||||
@ -3015,405 +3387,62 @@ elf_x86_64_convert_load (bfd *abfd, asection *sec,
|
|||||||
goto error_return;
|
goto error_return;
|
||||||
}
|
}
|
||||||
|
|
||||||
is_pic = bfd_link_pic (link_info);
|
|
||||||
|
|
||||||
/* TRUE if we can convert only to R_X86_64_PC32. Enable it for
|
|
||||||
--no-relax. */
|
|
||||||
require_reloc_pc32
|
|
||||||
= link_info->disable_target_specific_optimizations > 1;
|
|
||||||
|
|
||||||
irelend = internal_relocs + sec->reloc_count;
|
irelend = internal_relocs + sec->reloc_count;
|
||||||
for (irel = internal_relocs; irel < irelend; irel++)
|
for (irel = internal_relocs; irel < irelend; irel++)
|
||||||
{
|
{
|
||||||
unsigned int r_type = ELF32_R_TYPE (irel->r_info);
|
unsigned int r_type = ELF32_R_TYPE (irel->r_info);
|
||||||
unsigned int r_symndx = htab->r_sym (irel->r_info);
|
unsigned int r_symndx;
|
||||||
unsigned int indx;
|
|
||||||
struct elf_link_hash_entry *h;
|
struct elf_link_hash_entry *h;
|
||||||
asection *tsec;
|
bfd_boolean converted;
|
||||||
char symtype;
|
|
||||||
bfd_vma toff, roff;
|
|
||||||
bfd_signed_vma raddend;
|
|
||||||
unsigned int opcode;
|
|
||||||
unsigned int modrm;
|
|
||||||
bfd_boolean relocx;
|
|
||||||
bfd_boolean to_reloc_pc32;
|
|
||||||
|
|
||||||
relocx = (r_type == R_X86_64_GOTPCRELX
|
if (r_type != R_X86_64_GOTPCRELX
|
||||||
|| r_type == R_X86_64_REX_GOTPCRELX);
|
&& r_type != R_X86_64_REX_GOTPCRELX
|
||||||
if (!relocx && r_type != R_X86_64_GOTPCREL)
|
&& r_type != R_X86_64_GOTPCREL)
|
||||||
continue;
|
continue;
|
||||||
|
|
||||||
roff = irel->r_offset;
|
r_symndx = htab->r_sym (irel->r_info);
|
||||||
if (roff < (r_type == R_X86_64_REX_GOTPCRELX ? 3 : 2))
|
|
||||||
continue;
|
|
||||||
|
|
||||||
raddend = irel->r_addend;
|
|
||||||
/* Addend for 32-bit PC-relative relocation must be -4. */
|
|
||||||
if (raddend != -4)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
opcode = bfd_get_8 (abfd, contents + roff - 2);
|
|
||||||
|
|
||||||
/* Convert mov to lea since it has been done for a while. */
|
|
||||||
if (opcode != 0x8b)
|
|
||||||
{
|
|
||||||
/* Only convert R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX
|
|
||||||
for call, jmp or one of adc, add, and, cmp, or, sbb, sub,
|
|
||||||
test, xor instructions. */
|
|
||||||
if (!relocx)
|
|
||||||
continue;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* We convert only to R_X86_64_PC32:
|
|
||||||
1. Branch.
|
|
||||||
2. R_X86_64_GOTPCREL since we can't modify REX byte.
|
|
||||||
3. require_reloc_pc32 is true.
|
|
||||||
4. PIC.
|
|
||||||
*/
|
|
||||||
to_reloc_pc32 = (opcode == 0xff
|
|
||||||
|| !relocx
|
|
||||||
|| require_reloc_pc32
|
|
||||||
|| is_pic);
|
|
||||||
|
|
||||||
/* Get the symbol referred to by the reloc. */
|
|
||||||
if (r_symndx < symtab_hdr->sh_info)
|
if (r_symndx < symtab_hdr->sh_info)
|
||||||
{
|
h = elf_x86_64_get_local_sym_hash (htab, sec->owner,
|
||||||
Elf_Internal_Sym *isym;
|
(const Elf_Internal_Rela *) irel,
|
||||||
|
FALSE);
|
||||||
isym = bfd_sym_from_r_symndx (&htab->sym_cache,
|
|
||||||
abfd, r_symndx);
|
|
||||||
|
|
||||||
symtype = ELF_ST_TYPE (isym->st_info);
|
|
||||||
|
|
||||||
/* STT_GNU_IFUNC must keep GOTPCREL relocations and skip
|
|
||||||
relocation against undefined symbols. */
|
|
||||||
if (symtype == STT_GNU_IFUNC || isym->st_shndx == SHN_UNDEF)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
if (isym->st_shndx == SHN_ABS)
|
|
||||||
tsec = bfd_abs_section_ptr;
|
|
||||||
else if (isym->st_shndx == SHN_COMMON)
|
|
||||||
tsec = bfd_com_section_ptr;
|
|
||||||
else if (isym->st_shndx == SHN_X86_64_LCOMMON)
|
|
||||||
tsec = &_bfd_elf_large_com_section;
|
|
||||||
else
|
|
||||||
tsec = bfd_section_from_elf_index (abfd, isym->st_shndx);
|
|
||||||
|
|
||||||
h = NULL;
|
|
||||||
toff = isym->st_value;
|
|
||||||
}
|
|
||||||
else
|
else
|
||||||
{
|
{
|
||||||
indx = r_symndx - symtab_hdr->sh_info;
|
h = elf_sym_hashes (abfd)[r_symndx - symtab_hdr->sh_info];
|
||||||
h = elf_sym_hashes (abfd)[indx];
|
|
||||||
BFD_ASSERT (h != NULL);
|
|
||||||
|
|
||||||
while (h->root.type == bfd_link_hash_indirect
|
while (h->root.type == bfd_link_hash_indirect
|
||||||
|| h->root.type == bfd_link_hash_warning)
|
|| h->root.type == bfd_link_hash_warning)
|
||||||
h = (struct elf_link_hash_entry *) h->root.u.i.link;
|
h = (struct elf_link_hash_entry *) h->root.u.i.link;
|
||||||
|
|
||||||
/* STT_GNU_IFUNC must keep GOTPCREL relocations. We also
|
|
||||||
avoid optimizing GOTPCREL relocations againt _DYNAMIC
|
|
||||||
since ld.so may use its link-time address. */
|
|
||||||
if (h->type == STT_GNU_IFUNC)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
/* Undefined weak symbol is only bound locally in executable
|
|
||||||
and its reference is resolved as 0 without relocation
|
|
||||||
overflow. We can only perform this optimization for
|
|
||||||
GOTPCRELX relocations since we need to modify REX byte.
|
|
||||||
It is OK convert mov with R_X86_64_GOTPCREL to
|
|
||||||
R_X86_64_PC32. */
|
|
||||||
if ((relocx || opcode == 0x8b)
|
|
||||||
&& UNDEFINED_WEAK_RESOLVED_TO_ZERO (link_info,
|
|
||||||
TRUE,
|
|
||||||
elf_x86_64_hash_entry (h)))
|
|
||||||
{
|
|
||||||
if (opcode == 0xff)
|
|
||||||
{
|
|
||||||
/* Skip for branch instructions since R_X86_64_PC32
|
|
||||||
may overflow. */
|
|
||||||
if (require_reloc_pc32)
|
|
||||||
continue;
|
|
||||||
}
|
|
||||||
else if (relocx)
|
|
||||||
{
|
|
||||||
/* For non-branch instructions, we can convert to
|
|
||||||
R_X86_64_32/R_X86_64_32S since we know if there
|
|
||||||
is a REX byte. */
|
|
||||||
to_reloc_pc32 = FALSE;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Since we don't know the current PC when PIC is true,
|
|
||||||
we can't convert to R_X86_64_PC32. */
|
|
||||||
if (to_reloc_pc32 && is_pic)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
goto convert;
|
|
||||||
}
|
|
||||||
else if ((h->def_regular
|
|
||||||
|| h->root.type == bfd_link_hash_defined
|
|
||||||
|| h->root.type == bfd_link_hash_defweak)
|
|
||||||
&& h != htab->elf.hdynamic
|
|
||||||
&& SYMBOL_REFERENCES_LOCAL (link_info, h))
|
|
||||||
{
|
|
||||||
/* bfd_link_hash_new or bfd_link_hash_undefined is
|
|
||||||
set by an assignment in a linker script in
|
|
||||||
bfd_elf_record_link_assignment. */
|
|
||||||
if (h->def_regular
|
|
||||||
&& (h->root.type == bfd_link_hash_new
|
|
||||||
|| h->root.type == bfd_link_hash_undefined))
|
|
||||||
{
|
|
||||||
/* Skip since R_X86_64_32/R_X86_64_32S may overflow. */
|
|
||||||
if (require_reloc_pc32)
|
|
||||||
continue;
|
|
||||||
goto convert;
|
|
||||||
}
|
|
||||||
tsec = h->root.u.def.section;
|
|
||||||
toff = h->root.u.def.value;
|
|
||||||
symtype = h->type;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
continue;
|
|
||||||
}
|
}
|
||||||
|
|
||||||
/* We can only estimate relocation overflow for R_X86_64_PC32. */
|
/* STT_GNU_IFUNC must keep GOTPCREL relocations. */
|
||||||
if (!to_reloc_pc32)
|
if (h != NULL && h->type == STT_GNU_IFUNC)
|
||||||
goto convert;
|
continue;
|
||||||
|
|
||||||
if (tsec->sec_info_type == SEC_INFO_TYPE_MERGE)
|
converted = FALSE;
|
||||||
|
if (!elf_x86_64_convert_load_reloc (abfd, sec, contents, irel, h,
|
||||||
|
&converted, link_info))
|
||||||
|
goto error_return;
|
||||||
|
|
||||||
|
if (converted)
|
||||||
{
|
{
|
||||||
/* At this stage in linking, no SEC_MERGE symbol has been
|
changed = converted;
|
||||||
adjusted, so all references to such symbols need to be
|
if (h)
|
||||||
passed through _bfd_merged_section_offset. (Later, in
|
|
||||||
relocate_section, all SEC_MERGE symbols *except* for
|
|
||||||
section symbols have been adjusted.)
|
|
||||||
|
|
||||||
gas may reduce relocations against symbols in SEC_MERGE
|
|
||||||
sections to a relocation against the section symbol when
|
|
||||||
the original addend was zero. When the reloc is against
|
|
||||||
a section symbol we should include the addend in the
|
|
||||||
offset passed to _bfd_merged_section_offset, since the
|
|
||||||
location of interest is the original symbol. On the
|
|
||||||
other hand, an access to "sym+addend" where "sym" is not
|
|
||||||
a section symbol should not include the addend; Such an
|
|
||||||
access is presumed to be an offset from "sym"; The
|
|
||||||
location of interest is just "sym". */
|
|
||||||
if (symtype == STT_SECTION)
|
|
||||||
toff += raddend;
|
|
||||||
|
|
||||||
toff = _bfd_merged_section_offset (abfd, &tsec,
|
|
||||||
elf_section_data (tsec)->sec_info,
|
|
||||||
toff);
|
|
||||||
|
|
||||||
if (symtype != STT_SECTION)
|
|
||||||
toff += raddend;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
toff += raddend;
|
|
||||||
|
|
||||||
/* Don't convert if R_X86_64_PC32 relocation overflows. */
|
|
||||||
if (tsec->output_section == sec->output_section)
|
|
||||||
{
|
|
||||||
if ((toff - roff + 0x80000000) > 0xffffffff)
|
|
||||||
continue;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
bfd_signed_vma distance;
|
|
||||||
|
|
||||||
/* At this point, we don't know the load addresses of TSEC
|
|
||||||
section nor SEC section. We estimate the distrance between
|
|
||||||
SEC and TSEC. We store the estimated distances in the
|
|
||||||
compressed_size field of the output section, which is only
|
|
||||||
used to decompress the compressed input section. */
|
|
||||||
if (sec->output_section->compressed_size == 0)
|
|
||||||
{
|
{
|
||||||
asection *asect;
|
if (h->got.refcount > 0)
|
||||||
bfd_size_type size = 0;
|
h->got.refcount -= 1;
|
||||||
for (asect = link_info->output_bfd->sections;
|
|
||||||
asect != NULL;
|
|
||||||
asect = asect->next)
|
|
||||||
/* Skip debug sections since compressed_size is used to
|
|
||||||
compress debug sections. */
|
|
||||||
if ((asect->flags & SEC_DEBUGGING) == 0)
|
|
||||||
{
|
|
||||||
asection *i;
|
|
||||||
for (i = asect->map_head.s;
|
|
||||||
i != NULL;
|
|
||||||
i = i->map_head.s)
|
|
||||||
{
|
|
||||||
size = align_power (size, i->alignment_power);
|
|
||||||
size += i->size;
|
|
||||||
}
|
|
||||||
asect->compressed_size = size;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Don't convert GOTPCREL relocations if TSEC isn't placed
|
|
||||||
after SEC. */
|
|
||||||
distance = (tsec->output_section->compressed_size
|
|
||||||
- sec->output_section->compressed_size);
|
|
||||||
if (distance < 0)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
/* Take PT_GNU_RELRO segment into account by adding
|
|
||||||
maxpagesize. */
|
|
||||||
if ((toff + distance + maxpagesize - roff + 0x80000000)
|
|
||||||
> 0xffffffff)
|
|
||||||
continue;
|
|
||||||
}
|
|
||||||
|
|
||||||
convert:
|
|
||||||
if (opcode == 0xff)
|
|
||||||
{
|
|
||||||
/* We have "call/jmp *foo@GOTPCREL(%rip)". */
|
|
||||||
unsigned int nop;
|
|
||||||
unsigned int disp;
|
|
||||||
bfd_vma nop_offset;
|
|
||||||
|
|
||||||
/* Convert R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX to
|
|
||||||
R_X86_64_PC32. */
|
|
||||||
modrm = bfd_get_8 (abfd, contents + roff - 1);
|
|
||||||
if (modrm == 0x25)
|
|
||||||
{
|
|
||||||
/* Convert to "jmp foo nop". */
|
|
||||||
modrm = 0xe9;
|
|
||||||
nop = NOP_OPCODE;
|
|
||||||
nop_offset = irel->r_offset + 3;
|
|
||||||
disp = bfd_get_32 (abfd, contents + irel->r_offset);
|
|
||||||
irel->r_offset -= 1;
|
|
||||||
bfd_put_32 (abfd, disp, contents + irel->r_offset);
|
|
||||||
}
|
}
|
||||||
else
|
else
|
||||||
{
|
{
|
||||||
/* Convert to "nop call foo". ADDR_PREFIX_OPCODE
|
if (local_got_refcounts != NULL
|
||||||
is a nop prefix. */
|
&& local_got_refcounts[r_symndx] > 0)
|
||||||
modrm = 0xe8;
|
local_got_refcounts[r_symndx] -= 1;
|
||||||
nop = link_info->call_nop_byte;
|
|
||||||
if (link_info->call_nop_as_suffix)
|
|
||||||
{
|
|
||||||
nop_offset = irel->r_offset + 3;
|
|
||||||
disp = bfd_get_32 (abfd, contents + irel->r_offset);
|
|
||||||
irel->r_offset -= 1;
|
|
||||||
bfd_put_32 (abfd, disp, contents + irel->r_offset);
|
|
||||||
}
|
|
||||||
else
|
|
||||||
nop_offset = irel->r_offset - 2;
|
|
||||||
}
|
}
|
||||||
bfd_put_8 (abfd, nop, contents + nop_offset);
|
|
||||||
bfd_put_8 (abfd, modrm, contents + irel->r_offset - 1);
|
|
||||||
r_type = R_X86_64_PC32;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
unsigned int rex;
|
|
||||||
unsigned int rex_mask = REX_R;
|
|
||||||
|
|
||||||
if (r_type == R_X86_64_REX_GOTPCRELX)
|
|
||||||
rex = bfd_get_8 (abfd, contents + roff - 3);
|
|
||||||
else
|
|
||||||
rex = 0;
|
|
||||||
|
|
||||||
if (opcode == 0x8b)
|
|
||||||
{
|
|
||||||
if (to_reloc_pc32)
|
|
||||||
{
|
|
||||||
/* Convert "mov foo@GOTPCREL(%rip), %reg" to
|
|
||||||
"lea foo(%rip), %reg". */
|
|
||||||
opcode = 0x8d;
|
|
||||||
r_type = R_X86_64_PC32;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* Convert "mov foo@GOTPCREL(%rip), %reg" to
|
|
||||||
"mov $foo, %reg". */
|
|
||||||
opcode = 0xc7;
|
|
||||||
modrm = bfd_get_8 (abfd, contents + roff - 1);
|
|
||||||
modrm = 0xc0 | (modrm & 0x38) >> 3;
|
|
||||||
if ((rex & REX_W) != 0
|
|
||||||
&& ABI_64_P (link_info->output_bfd))
|
|
||||||
{
|
|
||||||
/* Keep the REX_W bit in REX byte for LP64. */
|
|
||||||
r_type = R_X86_64_32S;
|
|
||||||
goto rewrite_modrm_rex;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* If the REX_W bit in REX byte isn't needed,
|
|
||||||
use R_X86_64_32 and clear the W bit to avoid
|
|
||||||
sign-extend imm32 to imm64. */
|
|
||||||
r_type = R_X86_64_32;
|
|
||||||
/* Clear the W bit in REX byte. */
|
|
||||||
rex_mask |= REX_W;
|
|
||||||
goto rewrite_modrm_rex;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* R_X86_64_PC32 isn't supported. */
|
|
||||||
if (to_reloc_pc32)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
modrm = bfd_get_8 (abfd, contents + roff - 1);
|
|
||||||
if (opcode == 0x85)
|
|
||||||
{
|
|
||||||
/* Convert "test %reg, foo@GOTPCREL(%rip)" to
|
|
||||||
"test $foo, %reg". */
|
|
||||||
modrm = 0xc0 | (modrm & 0x38) >> 3;
|
|
||||||
opcode = 0xf7;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* Convert "binop foo@GOTPCREL(%rip), %reg" to
|
|
||||||
"binop $foo, %reg". */
|
|
||||||
modrm = 0xc0 | (modrm & 0x38) >> 3 | (opcode & 0x3c);
|
|
||||||
opcode = 0x81;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Use R_X86_64_32 with 32-bit operand to avoid relocation
|
|
||||||
overflow when sign-extending imm32 to imm64. */
|
|
||||||
r_type = (rex & REX_W) != 0 ? R_X86_64_32S : R_X86_64_32;
|
|
||||||
|
|
||||||
rewrite_modrm_rex:
|
|
||||||
bfd_put_8 (abfd, modrm, contents + roff - 1);
|
|
||||||
|
|
||||||
if (rex)
|
|
||||||
{
|
|
||||||
/* Move the R bit to the B bit in REX byte. */
|
|
||||||
rex = (rex & ~rex_mask) | (rex & REX_R) >> 2;
|
|
||||||
bfd_put_8 (abfd, rex, contents + roff - 3);
|
|
||||||
}
|
|
||||||
|
|
||||||
/* No addend for R_X86_64_32/R_X86_64_32S relocations. */
|
|
||||||
irel->r_addend = 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
bfd_put_8 (abfd, opcode, contents + roff - 2);
|
|
||||||
}
|
|
||||||
|
|
||||||
irel->r_info = htab->r_info (r_symndx, r_type);
|
|
||||||
changed_contents = TRUE;
|
|
||||||
changed_relocs = TRUE;
|
|
||||||
|
|
||||||
if (h)
|
|
||||||
{
|
|
||||||
if (h->got.refcount > 0)
|
|
||||||
h->got.refcount -= 1;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
if (local_got_refcounts != NULL
|
|
||||||
&& local_got_refcounts[r_symndx] > 0)
|
|
||||||
local_got_refcounts[r_symndx] -= 1;
|
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
if (contents != NULL
|
if (contents != NULL
|
||||||
&& elf_section_data (sec)->this_hdr.contents != contents)
|
&& elf_section_data (sec)->this_hdr.contents != contents)
|
||||||
{
|
{
|
||||||
if (!changed_contents && !link_info->keep_memory)
|
if (!changed && !link_info->keep_memory)
|
||||||
free (contents);
|
free (contents);
|
||||||
else
|
else
|
||||||
{
|
{
|
||||||
@ -3424,7 +3453,7 @@ rewrite_modrm_rex:
|
|||||||
|
|
||||||
if (elf_section_data (sec)->relocs != internal_relocs)
|
if (elf_section_data (sec)->relocs != internal_relocs)
|
||||||
{
|
{
|
||||||
if (!changed_relocs)
|
if (!changed)
|
||||||
free (internal_relocs);
|
free (internal_relocs);
|
||||||
else
|
else
|
||||||
elf_section_data (sec)->relocs = internal_relocs;
|
elf_section_data (sec)->relocs = internal_relocs;
|
||||||
|
|||||||
Reference in New Issue
Block a user