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8df9fc9d6a
the reloc is against read-only section. (elf64_x86_64_size_dynamic_sections): Use DF_TEXTREL flag instead of looking up section names for DT_TEXTREL. (elf64_x86_64_reloc_type_class): New. (elf_backend_reloc_type_class): Define.
1983 lines
61 KiB
C
1983 lines
61 KiB
C
/* X86-64 specific support for 64-bit ELF
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Copyright 2000, 2001 Free Software Foundation, Inc.
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Contributed by Jan Hubicka <jh@suse.cz>.
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This file is part of BFD, the Binary File Descriptor library.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
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#include "bfd.h"
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#include "sysdep.h"
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#include "libbfd.h"
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#include "elf-bfd.h"
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#include "elf/x86-64.h"
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/* We use only the RELA entries. */
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#define USE_RELA
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/* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
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#define MINUS_ONE (~ (bfd_vma) 0)
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/* The relocation "howto" table. Order of fields:
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type, size, bitsize, pc_relative, complain_on_overflow,
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special_function, name, partial_inplace, src_mask, dst_pack, pcrel_offset. */
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static reloc_howto_type x86_64_elf_howto_table[] =
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{
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HOWTO(R_X86_64_NONE, 0, 0, 0, false, 0, complain_overflow_dont,
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bfd_elf_generic_reloc, "R_X86_64_NONE", false, 0x00000000, 0x00000000,
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false),
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HOWTO(R_X86_64_64, 0, 4, 64, false, 0, complain_overflow_bitfield,
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bfd_elf_generic_reloc, "R_X86_64_64", false, MINUS_ONE, MINUS_ONE,
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false),
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HOWTO(R_X86_64_PC32, 0, 4, 32, true, 0, complain_overflow_signed,
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bfd_elf_generic_reloc, "R_X86_64_PC32", false, 0xffffffff, 0xffffffff,
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true),
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HOWTO(R_X86_64_GOT32, 0, 4, 32, false, 0, complain_overflow_signed,
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bfd_elf_generic_reloc, "R_X86_64_GOT32", false, 0xffffffff, 0xffffffff,
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false),
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HOWTO(R_X86_64_PLT32, 0, 4, 32, true, 0, complain_overflow_signed,
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bfd_elf_generic_reloc, "R_X86_64_PLT32", false, 0xffffffff, 0xffffffff,
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true),
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HOWTO(R_X86_64_COPY, 0, 4, 32, false, 0, complain_overflow_bitfield,
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bfd_elf_generic_reloc, "R_X86_64_COPY", false, 0xffffffff, 0xffffffff,
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false),
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HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, false, 0, complain_overflow_bitfield,
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bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", false, MINUS_ONE,
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MINUS_ONE, false),
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HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, false, 0, complain_overflow_bitfield,
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bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", false, MINUS_ONE,
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MINUS_ONE, false),
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HOWTO(R_X86_64_RELATIVE, 0, 4, 64, false, 0, complain_overflow_bitfield,
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bfd_elf_generic_reloc, "R_X86_64_RELATIVE", false, MINUS_ONE,
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MINUS_ONE, false),
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HOWTO(R_X86_64_GOTPCREL, 0, 4, 32, true,0 , complain_overflow_signed,
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bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", false, 0xffffffff,
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0xffffffff, true),
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HOWTO(R_X86_64_32, 0, 4, 32, false, 0, complain_overflow_unsigned,
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bfd_elf_generic_reloc, "R_X86_64_32", false, 0xffffffff, 0xffffffff,
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false),
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HOWTO(R_X86_64_32S, 0, 4, 32, false, 0, complain_overflow_signed,
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bfd_elf_generic_reloc, "R_X86_64_32S", false, 0xffffffff, 0xffffffff,
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false),
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HOWTO(R_X86_64_16, 0, 1, 16, false, 0, complain_overflow_bitfield,
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bfd_elf_generic_reloc, "R_X86_64_16", false, 0xffff, 0xffff, false),
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HOWTO(R_X86_64_PC16,0, 1, 16, true, 0, complain_overflow_bitfield,
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bfd_elf_generic_reloc, "R_X86_64_PC16", false, 0xffff, 0xffff, true),
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HOWTO(R_X86_64_8, 0, 0, 8, false, 0, complain_overflow_signed,
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bfd_elf_generic_reloc, "R_X86_64_8", false, 0xff, 0xff, false),
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HOWTO(R_X86_64_PC8, 0, 0, 8, true, 0, complain_overflow_signed,
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bfd_elf_generic_reloc, "R_X86_64_PC8", false, 0xff, 0xff, true),
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/* GNU extension to record C++ vtable hierarchy. */
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HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, false, 0, complain_overflow_dont,
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NULL, "R_X86_64_GNU_VTINHERIT", false, 0, 0, false),
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/* GNU extension to record C++ vtable member usage. */
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HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, false, 0, complain_overflow_dont,
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_bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", false, 0, 0,
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false)
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};
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/* Map BFD relocs to the x86_64 elf relocs. */
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struct elf_reloc_map
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{
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bfd_reloc_code_real_type bfd_reloc_val;
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unsigned char elf_reloc_val;
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};
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static CONST struct elf_reloc_map x86_64_reloc_map[] =
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{
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{ BFD_RELOC_NONE, R_X86_64_NONE, },
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{ BFD_RELOC_64, R_X86_64_64, },
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{ BFD_RELOC_32_PCREL, R_X86_64_PC32, },
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{ BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,},
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{ BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,},
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{ BFD_RELOC_X86_64_COPY, R_X86_64_COPY, },
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{ BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, },
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{ BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, },
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{ BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, },
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{ BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, },
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{ BFD_RELOC_32, R_X86_64_32, },
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{ BFD_RELOC_X86_64_32S, R_X86_64_32S, },
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{ BFD_RELOC_16, R_X86_64_16, },
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{ BFD_RELOC_16_PCREL, R_X86_64_PC16, },
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{ BFD_RELOC_8, R_X86_64_8, },
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{ BFD_RELOC_8_PCREL, R_X86_64_PC8, },
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{ BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
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{ BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
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};
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static reloc_howto_type *elf64_x86_64_reloc_type_lookup
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PARAMS ((bfd *, bfd_reloc_code_real_type));
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static void elf64_x86_64_info_to_howto
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PARAMS ((bfd *, arelent *, Elf64_Internal_Rela *));
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static struct bfd_link_hash_table *elf64_x86_64_link_hash_table_create
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PARAMS ((bfd *));
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static boolean elf64_x86_64_elf_object_p PARAMS ((bfd *abfd));
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static boolean elf64_x86_64_check_relocs
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PARAMS ((bfd *, struct bfd_link_info *, asection *sec,
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const Elf_Internal_Rela *));
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static asection *elf64_x86_64_gc_mark_hook
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PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
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struct elf_link_hash_entry *, Elf_Internal_Sym *));
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static boolean elf64_x86_64_gc_sweep_hook
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PARAMS ((bfd *, struct bfd_link_info *, asection *,
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const Elf_Internal_Rela *));
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static struct bfd_hash_entry *elf64_x86_64_link_hash_newfunc
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PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
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static boolean elf64_x86_64_adjust_dynamic_symbol
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PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
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static boolean elf64_x86_64_size_dynamic_sections
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PARAMS ((bfd *, struct bfd_link_info *));
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static boolean elf64_x86_64_relocate_section
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PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
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Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
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static boolean elf64_x86_64_finish_dynamic_symbol
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PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
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Elf_Internal_Sym *sym));
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static boolean elf64_x86_64_finish_dynamic_sections
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PARAMS ((bfd *, struct bfd_link_info *));
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static enum elf_reloc_type_class elf64_x86_64_reloc_type_class PARAMS ((int));
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/* Given a BFD reloc type, return a HOWTO structure. */
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static reloc_howto_type *
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elf64_x86_64_reloc_type_lookup (abfd, code)
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bfd *abfd ATTRIBUTE_UNUSED;
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bfd_reloc_code_real_type code;
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{
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unsigned int i;
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for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
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i++)
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{
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if (x86_64_reloc_map[i].bfd_reloc_val == code)
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return &x86_64_elf_howto_table[(int)
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x86_64_reloc_map[i].elf_reloc_val];
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}
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return 0;
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}
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/* Given an x86_64 ELF reloc type, fill in an arelent structure. */
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static void
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elf64_x86_64_info_to_howto (abfd, cache_ptr, dst)
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bfd *abfd ATTRIBUTE_UNUSED;
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arelent *cache_ptr;
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Elf64_Internal_Rela *dst;
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{
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unsigned r_type, i;
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r_type = ELF64_R_TYPE (dst->r_info);
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if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT)
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{
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BFD_ASSERT (r_type <= (unsigned int) R_X86_64_PC8);
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i = r_type;
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}
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else
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{
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BFD_ASSERT (r_type < (unsigned int) R_X86_64_max);
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i = r_type - ((unsigned int) R_X86_64_GNU_VTINHERIT - R_X86_64_PC8 - 1);
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}
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cache_ptr->howto = &x86_64_elf_howto_table[i];
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BFD_ASSERT (r_type == cache_ptr->howto->type);
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}
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/* Functions for the x86-64 ELF linker. */
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/* The name of the dynamic interpreter. This is put in the .interp
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section. */
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#define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
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/* The size in bytes of an entry in the global offset table. */
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#define GOT_ENTRY_SIZE 8
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/* The size in bytes of an entry in the procedure linkage table. */
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#define PLT_ENTRY_SIZE 16
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/* The first entry in a procedure linkage table looks like this. See the
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SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
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static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
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{
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0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
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0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
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0x90, 0x90, 0x90, 0x90 /* pad out to 16 bytes with nops. */
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};
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/* Subsequent entries in a procedure linkage table look like this. */
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static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
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{
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0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
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0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
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0x68, /* pushq immediate */
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0, 0, 0, 0, /* replaced with index into relocation table. */
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0xe9, /* jmp relative */
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0, 0, 0, 0 /* replaced with offset to start of .plt0. */
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};
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/* The x86-64 linker needs to keep track of the number of relocs that
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it decides to copy in check_relocs for each symbol. This is so
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that it can discard PC relative relocs if it doesn't need them when
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linking with -Bsymbolic. We store the information in a field
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extending the regular ELF linker hash table. */
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/* This structure keeps track of the number of PC relative relocs we
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have copied for a given symbol. */
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struct elf64_x86_64_pcrel_relocs_copied
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{
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/* Next section. */
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struct elf64_x86_64_pcrel_relocs_copied *next;
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/* A section in dynobj. */
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asection *section;
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/* Number of relocs copied in this section. */
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bfd_size_type count;
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};
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/* x86-64 ELF linker hash entry. */
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struct elf64_x86_64_link_hash_entry
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{
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struct elf_link_hash_entry root;
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/* Number of PC relative relocs copied for this symbol. */
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struct elf64_x86_64_pcrel_relocs_copied *pcrel_relocs_copied;
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};
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/* x86-64 ELF linker hash table. */
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struct elf64_x86_64_link_hash_table
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{
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struct elf_link_hash_table root;
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};
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/* Declare this now that the above structures are defined. */
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static boolean elf64_x86_64_discard_copies
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PARAMS ((struct elf64_x86_64_link_hash_entry *, PTR));
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/* Traverse an x86-64 ELF linker hash table. */
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#define elf64_x86_64_link_hash_traverse(table, func, info) \
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(elf_link_hash_traverse \
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(&(table)->root, \
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(boolean (*) PARAMS ((struct elf_link_hash_entry *, PTR))) (func), \
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(info)))
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/* Get the x86-64 ELF linker hash table from a link_info structure. */
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#define elf64_x86_64_hash_table(p) \
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((struct elf64_x86_64_link_hash_table *) ((p)->hash))
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/* Create an entry in an x86-64 ELF linker hash table. */
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static struct bfd_hash_entry *
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elf64_x86_64_link_hash_newfunc (entry, table, string)
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struct bfd_hash_entry *entry;
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struct bfd_hash_table *table;
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const char *string;
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{
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struct elf64_x86_64_link_hash_entry *ret =
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(struct elf64_x86_64_link_hash_entry *) entry;
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/* Allocate the structure if it has not already been allocated by a
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subclass. */
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if (ret == (struct elf64_x86_64_link_hash_entry *) NULL)
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ret = ((struct elf64_x86_64_link_hash_entry *)
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bfd_hash_allocate (table,
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sizeof (struct elf64_x86_64_link_hash_entry)));
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if (ret == (struct elf64_x86_64_link_hash_entry *) NULL)
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return (struct bfd_hash_entry *) ret;
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/* Call the allocation method of the superclass. */
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ret = ((struct elf64_x86_64_link_hash_entry *)
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_bfd_elf_link_hash_newfunc ((struct bfd_hash_entry *) ret,
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table, string));
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if (ret != (struct elf64_x86_64_link_hash_entry *) NULL)
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{
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ret->pcrel_relocs_copied = NULL;
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}
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return (struct bfd_hash_entry *) ret;
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}
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/* Create an X86-64 ELF linker hash table. */
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static struct bfd_link_hash_table *
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elf64_x86_64_link_hash_table_create (abfd)
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bfd *abfd;
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{
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struct elf64_x86_64_link_hash_table *ret;
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ret = ((struct elf64_x86_64_link_hash_table *)
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bfd_alloc (abfd, sizeof (struct elf64_x86_64_link_hash_table)));
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if (ret == (struct elf64_x86_64_link_hash_table *) NULL)
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return NULL;
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if (! _bfd_elf_link_hash_table_init (&ret->root, abfd,
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elf64_x86_64_link_hash_newfunc))
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{
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bfd_release (abfd, ret);
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return NULL;
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}
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return &ret->root.root;
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}
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static boolean
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elf64_x86_64_elf_object_p (abfd)
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bfd *abfd;
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{
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/* Set the right machine number for an x86-64 elf64 file. */
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bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
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return true;
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}
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/* Look through the relocs for a section during the first phase, and
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allocate space in the global offset table or procedure linkage
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table. */
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static boolean
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elf64_x86_64_check_relocs (abfd, info, sec, relocs)
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bfd *abfd;
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struct bfd_link_info *info;
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asection *sec;
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const Elf_Internal_Rela *relocs;
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{
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bfd *dynobj;
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Elf_Internal_Shdr *symtab_hdr;
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struct elf_link_hash_entry **sym_hashes;
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bfd_signed_vma *local_got_refcounts;
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const Elf_Internal_Rela *rel;
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const Elf_Internal_Rela *rel_end;
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asection *sgot;
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asection *srelgot;
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asection *sreloc;
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if (info->relocateable)
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return true;
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dynobj = elf_hash_table (info)->dynobj;
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symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
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sym_hashes = elf_sym_hashes (abfd);
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local_got_refcounts = elf_local_got_refcounts (abfd);
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sgot = srelgot = sreloc = NULL;
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rel_end = relocs + sec->reloc_count;
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for (rel = relocs; rel < rel_end; rel++)
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{
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unsigned long r_symndx;
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struct elf_link_hash_entry *h;
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r_symndx = ELF64_R_SYM (rel->r_info);
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if (r_symndx < symtab_hdr->sh_info)
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h = NULL;
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else
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h = sym_hashes[r_symndx - symtab_hdr->sh_info];
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/* Some relocs require a global offset table. */
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if (dynobj == NULL)
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{
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switch (ELF64_R_TYPE (rel->r_info))
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{
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case R_X86_64_GOT32:
|
||
case R_X86_64_GOTPCREL:
|
||
elf_hash_table (info)->dynobj = dynobj = abfd;
|
||
if (! _bfd_elf_create_got_section (dynobj, info))
|
||
return false;
|
||
break;
|
||
}
|
||
}
|
||
|
||
switch (ELF64_R_TYPE (rel->r_info))
|
||
{
|
||
case R_X86_64_GOTPCREL:
|
||
case R_X86_64_GOT32:
|
||
/* This symbol requires a global offset table entry. */
|
||
|
||
if (sgot == NULL)
|
||
{
|
||
sgot = bfd_get_section_by_name (dynobj, ".got");
|
||
BFD_ASSERT (sgot != NULL);
|
||
}
|
||
|
||
if (srelgot == NULL && (h != NULL || info->shared))
|
||
{
|
||
srelgot = bfd_get_section_by_name (dynobj, ".rela.got");
|
||
if (srelgot == NULL)
|
||
{
|
||
srelgot = bfd_make_section (dynobj, ".rela.got");
|
||
if (srelgot == NULL
|
||
|| ! bfd_set_section_flags (dynobj, srelgot,
|
||
(SEC_ALLOC
|
||
| SEC_LOAD
|
||
| SEC_HAS_CONTENTS
|
||
| SEC_IN_MEMORY
|
||
| SEC_LINKER_CREATED
|
||
| SEC_READONLY))
|
||
|| ! bfd_set_section_alignment (dynobj, srelgot, 3))
|
||
return false;
|
||
}
|
||
}
|
||
|
||
if (h != NULL)
|
||
{
|
||
if (h->got.refcount == -1)
|
||
{
|
||
h->got.refcount = 1;
|
||
|
||
/* Make sure this symbol is output as a dynamic symbol. */
|
||
if (h->dynindx == -1)
|
||
{
|
||
if (! bfd_elf64_link_record_dynamic_symbol (info, h))
|
||
return false;
|
||
}
|
||
|
||
sgot->_raw_size += GOT_ENTRY_SIZE;
|
||
srelgot->_raw_size += sizeof (Elf64_External_Rela);
|
||
}
|
||
else
|
||
h->got.refcount += 1;
|
||
}
|
||
else
|
||
{
|
||
/* This is a global offset table entry for a local symbol. */
|
||
if (local_got_refcounts == NULL)
|
||
{
|
||
size_t size;
|
||
|
||
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_refcounts (abfd) = local_got_refcounts;
|
||
memset (local_got_refcounts, -1, size);
|
||
}
|
||
if (local_got_refcounts[r_symndx] == -1)
|
||
{
|
||
local_got_refcounts[r_symndx] = 1;
|
||
|
||
sgot->_raw_size += GOT_ENTRY_SIZE;
|
||
if (info->shared)
|
||
{
|
||
/* If we are generating a shared object, we need to
|
||
output a R_X86_64_RELATIVE reloc so that the dynamic
|
||
linker can adjust this GOT entry. */
|
||
srelgot->_raw_size += sizeof (Elf64_External_Rela);
|
||
}
|
||
}
|
||
else
|
||
local_got_refcounts[r_symndx] += 1;
|
||
}
|
||
break;
|
||
|
||
case R_X86_64_PLT32:
|
||
/* This symbol requires a procedure linkage table entry. We
|
||
actually build the entry in adjust_dynamic_symbol,
|
||
because this might be a case of linking PIC code which is
|
||
never referenced by a dynamic object, in which case we
|
||
don't need to generate a procedure linkage table entry
|
||
after all. */
|
||
|
||
/* If this is a local symbol, we resolve it directly without
|
||
creating a procedure linkage table entry. */
|
||
if (h == NULL)
|
||
continue;
|
||
|
||
h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
|
||
if (h->plt.refcount == -1)
|
||
h->plt.refcount = 1;
|
||
else
|
||
h->plt.refcount += 1;
|
||
break;
|
||
|
||
case R_X86_64_8:
|
||
case R_X86_64_16:
|
||
case R_X86_64_32:
|
||
case R_X86_64_64:
|
||
case R_X86_64_32S:
|
||
case R_X86_64_PC32:
|
||
if (h != NULL)
|
||
h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF;
|
||
|
||
/* If we are creating a shared library, and this is a reloc
|
||
against a global symbol, or a non PC relative reloc
|
||
against a local symbol, then we need to copy the reloc
|
||
into the shared library. However, if we are linking with
|
||
-Bsymbolic, we do not need to copy a reloc against a
|
||
global symbol which is defined in an object we are
|
||
including in the link (i.e., DEF_REGULAR is set). At
|
||
this point we have not seen all the input files, so it is
|
||
possible that DEF_REGULAR is not set now but will be set
|
||
later (it is never cleared). We account for that
|
||
possibility below by storing information in the
|
||
pcrel_relocs_copied field of the hash table entry.
|
||
A similar situation occurs when creating shared libraries
|
||
and symbol visibility changes render the symbol local. */
|
||
if (info->shared
|
||
&& (sec->flags & SEC_ALLOC) != 0
|
||
&& (((ELF64_R_TYPE (rel->r_info) != R_X86_64_PC8)
|
||
&& (ELF64_R_TYPE (rel->r_info) != R_X86_64_PC16)
|
||
&& (ELF64_R_TYPE (rel->r_info) != R_X86_64_PC32))
|
||
|| (h != NULL
|
||
&& (! info->symbolic
|
||
|| (h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_DEF_REGULAR) == 0))))
|
||
{
|
||
/* When creating a shared object, we must copy these
|
||
reloc types into the output file. We create a reloc
|
||
section in dynobj and make room for this reloc. */
|
||
if (sreloc == NULL)
|
||
{
|
||
const char *name;
|
||
|
||
name = (bfd_elf_string_from_elf_section
|
||
(abfd,
|
||
elf_elfheader (abfd)->e_shstrndx,
|
||
elf_section_data (sec)->rel_hdr.sh_name));
|
||
if (name == NULL)
|
||
return false;
|
||
|
||
BFD_ASSERT (strncmp (name, ".rela", 5) == 0
|
||
&& strcmp (bfd_get_section_name (abfd, sec),
|
||
name + 5) == 0);
|
||
|
||
sreloc = bfd_get_section_by_name (dynobj, name);
|
||
if (sreloc == NULL)
|
||
{
|
||
flagword flags;
|
||
|
||
sreloc = bfd_make_section (dynobj, name);
|
||
flags = (SEC_HAS_CONTENTS | SEC_READONLY
|
||
| SEC_IN_MEMORY | SEC_LINKER_CREATED);
|
||
if ((sec->flags & SEC_ALLOC) != 0)
|
||
flags |= SEC_ALLOC | SEC_LOAD;
|
||
if (sreloc == NULL
|
||
|| ! bfd_set_section_flags (dynobj, sreloc, flags)
|
||
|| ! bfd_set_section_alignment (dynobj, sreloc, 3))
|
||
return false;
|
||
}
|
||
if (sec->flags & SEC_READONLY)
|
||
info->flags |= DF_TEXTREL;
|
||
}
|
||
|
||
sreloc->_raw_size += sizeof (Elf64_External_Rela);
|
||
|
||
/* If this is a global symbol, we count the number of PC
|
||
relative relocations we have entered for this symbol,
|
||
so that we can discard them later as necessary. Note
|
||
that this function is only called if we are using an
|
||
elf64_x86_64 linker hash table, which means that h is
|
||
really a pointer to an elf64_x86_64_link_hash_entry. */
|
||
if (h != NULL
|
||
&& ((ELF64_R_TYPE (rel->r_info) == R_X86_64_PC8)
|
||
|| (ELF64_R_TYPE (rel->r_info) == R_X86_64_PC16)
|
||
|| (ELF64_R_TYPE (rel->r_info) == R_X86_64_PC32)))
|
||
{
|
||
struct elf64_x86_64_link_hash_entry *eh;
|
||
struct elf64_x86_64_pcrel_relocs_copied *p;
|
||
|
||
eh = (struct elf64_x86_64_link_hash_entry *) h;
|
||
|
||
for (p = eh->pcrel_relocs_copied; p != NULL; p = p->next)
|
||
if (p->section == sreloc)
|
||
break;
|
||
|
||
if (p == NULL)
|
||
{
|
||
p = ((struct elf64_x86_64_pcrel_relocs_copied *)
|
||
bfd_alloc (dynobj, sizeof *p));
|
||
if (p == NULL)
|
||
return false;
|
||
p->next = eh->pcrel_relocs_copied;
|
||
eh->pcrel_relocs_copied = p;
|
||
p->section = sreloc;
|
||
p->count = 0;
|
||
}
|
||
|
||
++p->count;
|
||
}
|
||
}
|
||
break;
|
||
|
||
/* This relocation describes the C++ object vtable hierarchy.
|
||
Reconstruct it for later use during GC. */
|
||
case R_X86_64_GNU_VTINHERIT:
|
||
if (!_bfd_elf64_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
|
||
return false;
|
||
break;
|
||
|
||
/* This relocation describes which C++ vtable entries are actually
|
||
used. Record for later use during GC. */
|
||
case R_X86_64_GNU_VTENTRY:
|
||
if (!_bfd_elf64_gc_record_vtentry (abfd, sec, h, rel->r_addend))
|
||
return false;
|
||
break;
|
||
}
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Return the section that should be marked against GC for a given
|
||
relocation. */
|
||
|
||
static asection *
|
||
elf64_x86_64_gc_mark_hook (abfd, info, rel, h, sym)
|
||
bfd *abfd;
|
||
struct bfd_link_info *info ATTRIBUTE_UNUSED;
|
||
Elf_Internal_Rela *rel ATTRIBUTE_UNUSED;
|
||
struct elf_link_hash_entry *h;
|
||
Elf_Internal_Sym *sym;
|
||
{
|
||
if (h != NULL)
|
||
{
|
||
switch (ELF64_R_TYPE (rel->r_info))
|
||
{
|
||
case R_X86_64_GNU_VTINHERIT:
|
||
case R_X86_64_GNU_VTENTRY:
|
||
break;
|
||
|
||
default:
|
||
switch (h->root.type)
|
||
{
|
||
case bfd_link_hash_defined:
|
||
case bfd_link_hash_defweak:
|
||
return h->root.u.def.section;
|
||
|
||
case bfd_link_hash_common:
|
||
return h->root.u.c.p->section;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
else
|
||
{
|
||
if (!(elf_bad_symtab (abfd)
|
||
&& ELF_ST_BIND (sym->st_info) != STB_LOCAL)
|
||
&& ! ((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
|
||
&& sym->st_shndx != SHN_COMMON))
|
||
{
|
||
return bfd_section_from_elf_index (abfd, sym->st_shndx);
|
||
}
|
||
}
|
||
|
||
return NULL;
|
||
}
|
||
|
||
/* Update the got entry reference counts for the section being removed. */
|
||
|
||
static boolean
|
||
elf64_x86_64_gc_sweep_hook (abfd, info, sec, relocs)
|
||
bfd *abfd;
|
||
struct bfd_link_info *info ATTRIBUTE_UNUSED;
|
||
asection *sec;
|
||
const Elf_Internal_Rela *relocs;
|
||
{
|
||
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, ".rela.got");
|
||
|
||
relend = relocs + sec->reloc_count;
|
||
for (rel = relocs; rel < relend; rel++)
|
||
switch (ELF64_R_TYPE (rel->r_info))
|
||
{
|
||
case R_X86_64_GOT32:
|
||
case R_X86_64_GOTPCREL:
|
||
r_symndx = ELF64_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 -= GOT_ENTRY_SIZE;
|
||
srelgot->_raw_size -= sizeof (Elf64_External_Rela);
|
||
}
|
||
}
|
||
}
|
||
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 -= GOT_ENTRY_SIZE;
|
||
if (info->shared)
|
||
srelgot->_raw_size -= sizeof (Elf64_External_Rela);
|
||
}
|
||
}
|
||
}
|
||
break;
|
||
|
||
case R_X86_64_PLT32:
|
||
r_symndx = ELF64_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;
|
||
}
|
||
|
||
/* Adjust a symbol defined by a dynamic object and referenced by a
|
||
regular object. The current definition is in some section of the
|
||
dynamic object, but we're not including those sections. We have to
|
||
change the definition to something the rest of the link can
|
||
understand. */
|
||
|
||
static boolean
|
||
elf64_x86_64_adjust_dynamic_symbol (info, h)
|
||
struct bfd_link_info *info;
|
||
struct elf_link_hash_entry *h;
|
||
{
|
||
bfd *dynobj;
|
||
asection *s;
|
||
unsigned int power_of_two;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
|
||
/* Make sure we know what is going on here. */
|
||
BFD_ASSERT (dynobj != NULL
|
||
&& ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
|
||
|| h->weakdef != NULL
|
||
|| ((h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_DEF_DYNAMIC) != 0
|
||
&& (h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_REF_REGULAR) != 0
|
||
&& (h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_DEF_REGULAR) == 0)));
|
||
|
||
/* If this is a function, put it in the procedure linkage table. We
|
||
will fill in the contents of the procedure linkage table later,
|
||
when we know the address of the .got section. */
|
||
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)
|
||
|| (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, 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;
|
||
}
|
||
|
||
/* Make sure this symbol is output as a dynamic symbol. */
|
||
if (h->dynindx == -1)
|
||
{
|
||
if (! bfd_elf64_link_record_dynamic_symbol (info, h))
|
||
return false;
|
||
}
|
||
|
||
s = bfd_get_section_by_name (dynobj, ".plt");
|
||
BFD_ASSERT (s != NULL);
|
||
|
||
/* If this is the first .plt entry, make room for the special
|
||
first entry. */
|
||
if (s->_raw_size == 0)
|
||
s->_raw_size = PLT_ENTRY_SIZE;
|
||
|
||
/* If this symbol is not defined in a regular file, and we are
|
||
not generating a shared library, then set the symbol to this
|
||
location in the .plt. This is required to make function
|
||
pointers compare as equal between the normal executable and
|
||
the shared library. */
|
||
if (! info->shared
|
||
&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
|
||
{
|
||
h->root.u.def.section = s;
|
||
h->root.u.def.value = s->_raw_size;
|
||
}
|
||
|
||
h->plt.offset = s->_raw_size;
|
||
|
||
/* Make room for this entry. */
|
||
s->_raw_size += PLT_ENTRY_SIZE;
|
||
|
||
/* 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 += GOT_ENTRY_SIZE;
|
||
|
||
/* We also need to make an entry in the .rela.plt section. */
|
||
s = bfd_get_section_by_name (dynobj, ".rela.plt");
|
||
BFD_ASSERT (s != NULL);
|
||
s->_raw_size += sizeof (Elf64_External_Rela);
|
||
|
||
return true;
|
||
}
|
||
|
||
/* If this is a weak symbol, and there is a real definition, the
|
||
processor independent code will have arranged for us to see the
|
||
real definition first, and we can just use the same value. */
|
||
if (h->weakdef != NULL)
|
||
{
|
||
BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
|
||
|| h->weakdef->root.type == bfd_link_hash_defweak);
|
||
h->root.u.def.section = h->weakdef->root.u.def.section;
|
||
h->root.u.def.value = h->weakdef->root.u.def.value;
|
||
return true;
|
||
}
|
||
|
||
/* This is a reference to a symbol defined by a dynamic object which
|
||
is not a function. */
|
||
|
||
/* If we are creating a shared library, we must presume that the
|
||
only references to the symbol are via the global offset table.
|
||
For such cases we need not do anything here; the relocations will
|
||
be handled correctly by relocate_section. */
|
||
if (info->shared)
|
||
return true;
|
||
|
||
/* If there are no references to this symbol that do not use the
|
||
GOT, we don't need to generate a copy reloc. */
|
||
if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0)
|
||
return true;
|
||
|
||
/* We must allocate the symbol in our .dynbss section, which will
|
||
become part of the .bss section of the executable. There will be
|
||
an entry for this symbol in the .dynsym section. The dynamic
|
||
object will contain position independent code, so all references
|
||
from the dynamic object to this symbol will go through the global
|
||
offset table. The dynamic linker will use the .dynsym entry to
|
||
determine the address it must put in the global offset table, so
|
||
both the dynamic object and the regular object will refer to the
|
||
same memory location for the variable. */
|
||
|
||
s = bfd_get_section_by_name (dynobj, ".dynbss");
|
||
BFD_ASSERT (s != NULL);
|
||
|
||
/* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
|
||
to copy the initial value out of the dynamic object and into the
|
||
runtime process image. We need to remember the offset into the
|
||
.rela.bss section we are going to use. */
|
||
if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
|
||
{
|
||
asection *srel;
|
||
|
||
srel = bfd_get_section_by_name (dynobj, ".rela.bss");
|
||
BFD_ASSERT (srel != NULL);
|
||
srel->_raw_size += sizeof (Elf64_External_Rela);
|
||
h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
|
||
}
|
||
|
||
/* We need to figure out the alignment required for this symbol. I
|
||
have no idea how ELF linkers handle this. 16-bytes is the size
|
||
of the largest type that requires hard alignment -- long double. */
|
||
/* FIXME: This is VERY ugly. Should be fixed for all architectures using
|
||
this construct. */
|
||
power_of_two = bfd_log2 (h->size);
|
||
if (power_of_two > 4)
|
||
power_of_two = 4;
|
||
|
||
/* Apply the required alignment. */
|
||
s->_raw_size = BFD_ALIGN (s->_raw_size, (bfd_size_type) (1 << power_of_two));
|
||
if (power_of_two > bfd_get_section_alignment (dynobj, s))
|
||
{
|
||
if (! bfd_set_section_alignment (dynobj, s, power_of_two))
|
||
return false;
|
||
}
|
||
|
||
/* Define the symbol as being at this point in the section. */
|
||
h->root.u.def.section = s;
|
||
h->root.u.def.value = s->_raw_size;
|
||
|
||
/* Increment the section size to make room for the symbol. */
|
||
s->_raw_size += h->size;
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Set the sizes of the dynamic sections. */
|
||
|
||
static boolean
|
||
elf64_x86_64_size_dynamic_sections (output_bfd, info)
|
||
bfd *output_bfd ATTRIBUTE_UNUSED;
|
||
struct bfd_link_info *info;
|
||
{
|
||
bfd *dynobj;
|
||
asection *s;
|
||
boolean plt;
|
||
boolean relocs;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
BFD_ASSERT (dynobj != NULL);
|
||
|
||
if (elf_hash_table (info)->dynamic_sections_created)
|
||
{
|
||
/* Set the contents of the .interp section to the interpreter. */
|
||
if (! info->shared)
|
||
{
|
||
s = bfd_get_section_by_name (dynobj, ".interp");
|
||
BFD_ASSERT (s != NULL);
|
||
s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
|
||
s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* We may have created entries in the .rela.got section.
|
||
However, if we are not creating the dynamic sections, we will
|
||
not actually use these entries. Reset the size of .rela.got,
|
||
which will cause it to get stripped from the output file
|
||
below. */
|
||
s = bfd_get_section_by_name (dynobj, ".rela.got");
|
||
if (s != NULL)
|
||
s->_raw_size = 0;
|
||
}
|
||
|
||
/* If this is a -Bsymbolic shared link, then we need to discard all
|
||
PC relative relocs against symbols defined in a regular object.
|
||
We allocated space for them in the check_relocs routine, but we
|
||
will not fill them in in the relocate_section routine. */
|
||
if (info->shared)
|
||
elf64_x86_64_link_hash_traverse (elf64_x86_64_hash_table (info),
|
||
elf64_x86_64_discard_copies,
|
||
(PTR) info);
|
||
|
||
/* The check_relocs and adjust_dynamic_symbol entry points have
|
||
determined the sizes of the various dynamic sections. Allocate
|
||
memory for them. */
|
||
plt = relocs = false;
|
||
for (s = dynobj->sections; s != NULL; s = s->next)
|
||
{
|
||
const char *name;
|
||
boolean strip;
|
||
|
||
if ((s->flags & SEC_LINKER_CREATED) == 0)
|
||
continue;
|
||
|
||
/* It's OK to base decisions on the section name, because none
|
||
of the dynobj section names depend upon the input files. */
|
||
name = bfd_get_section_name (dynobj, s);
|
||
|
||
strip = false;
|
||
if (strcmp (name, ".plt") == 0)
|
||
{
|
||
if (s->_raw_size == 0)
|
||
{
|
||
/* Strip this section if we don't need it; see the
|
||
comment below. */
|
||
strip = true;
|
||
}
|
||
else
|
||
{
|
||
/* Remember whether there is a PLT. */
|
||
plt = true;
|
||
}
|
||
}
|
||
else if (strncmp (name, ".rela", 5) == 0)
|
||
{
|
||
if (s->_raw_size == 0)
|
||
{
|
||
/* If we don't need this section, strip it from the
|
||
output file. This is mostly to handle .rela.bss and
|
||
.rela.plt. We must create both sections in
|
||
create_dynamic_sections, because they must be created
|
||
before the linker maps input sections to output
|
||
sections. The linker does that before
|
||
adjust_dynamic_symbol is called, and it is that
|
||
function which decides whether anything needs to go
|
||
into these sections. */
|
||
strip = true;
|
||
}
|
||
else
|
||
{
|
||
if (strcmp (name, ".rela.plt") != 0)
|
||
relocs = true;
|
||
|
||
/* We use the reloc_count field as a counter if we need
|
||
to copy relocs into the output file. */
|
||
s->reloc_count = 0;
|
||
}
|
||
}
|
||
else if (strncmp (name, ".got", 4) != 0)
|
||
{
|
||
/* It's not one of our sections, so don't allocate space. */
|
||
continue;
|
||
}
|
||
|
||
if (strip)
|
||
{
|
||
_bfd_strip_section_from_output (info, s);
|
||
continue;
|
||
}
|
||
|
||
/* Allocate memory for the section contents. We use bfd_zalloc
|
||
here in case unused entries are not reclaimed before the
|
||
section's contents are written out. This should not happen,
|
||
but this way if it does, we get a R_X86_64_NONE reloc instead
|
||
of garbage. */
|
||
s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
|
||
if (s->contents == NULL && s->_raw_size != 0)
|
||
return false;
|
||
}
|
||
|
||
if (elf_hash_table (info)->dynamic_sections_created)
|
||
{
|
||
/* Add some entries to the .dynamic section. We fill in the
|
||
values later, in elf64_x86_64_finish_dynamic_sections, but we
|
||
must add the entries now so that we get the correct size for
|
||
the .dynamic section. The DT_DEBUG entry is filled in by the
|
||
dynamic linker and used by the debugger. */
|
||
if (! info->shared)
|
||
{
|
||
if (! bfd_elf64_add_dynamic_entry (info, DT_DEBUG, 0))
|
||
return false;
|
||
}
|
||
|
||
if (plt)
|
||
{
|
||
if (! bfd_elf64_add_dynamic_entry (info, DT_PLTGOT, 0)
|
||
|| ! bfd_elf64_add_dynamic_entry (info, DT_PLTRELSZ, 0)
|
||
|| ! bfd_elf64_add_dynamic_entry (info, DT_PLTREL, DT_RELA)
|
||
|| ! bfd_elf64_add_dynamic_entry (info, DT_JMPREL, 0))
|
||
return false;
|
||
}
|
||
|
||
if (relocs)
|
||
{
|
||
if (! bfd_elf64_add_dynamic_entry (info, DT_RELA, 0)
|
||
|| ! bfd_elf64_add_dynamic_entry (info, DT_RELASZ, 0)
|
||
|| ! bfd_elf64_add_dynamic_entry (info, DT_RELAENT,
|
||
sizeof (Elf64_External_Rela)))
|
||
return false;
|
||
}
|
||
|
||
if ((info->flags & DF_TEXTREL) != 0)
|
||
{
|
||
if (! bfd_elf64_add_dynamic_entry (info, DT_TEXTREL, 0))
|
||
return false;
|
||
}
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
/* This function is called via elf64_x86_64_link_hash_traverse if we are
|
||
creating a shared object. In the -Bsymbolic case, it discards the
|
||
space allocated to copy PC relative relocs against symbols which
|
||
are defined in regular objects. For the normal non-symbolic case,
|
||
we also discard space for relocs that have become local due to
|
||
symbol visibility changes. We allocated space for them in the
|
||
check_relocs routine, but we won't fill them in in the
|
||
relocate_section routine. */
|
||
|
||
static boolean
|
||
elf64_x86_64_discard_copies (h, inf)
|
||
struct elf64_x86_64_link_hash_entry *h;
|
||
PTR inf;
|
||
{
|
||
struct elf64_x86_64_pcrel_relocs_copied *s;
|
||
struct bfd_link_info *info = (struct bfd_link_info *) inf;
|
||
|
||
/* If a symbol has been forced local or we have found a regular
|
||
definition for the symbolic link case, then we won't be needing
|
||
any relocs. */
|
||
if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
|
||
&& ((h->root.elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0
|
||
|| info->symbolic))
|
||
{
|
||
for (s = h->pcrel_relocs_copied; s != NULL; s = s->next)
|
||
s->section->_raw_size -= s->count * sizeof (Elf64_External_Rela);
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Relocate an x86_64 ELF section. */
|
||
|
||
static boolean
|
||
elf64_x86_64_relocate_section (output_bfd, info, input_bfd, input_section,
|
||
contents, relocs, local_syms, local_sections)
|
||
bfd *output_bfd;
|
||
struct bfd_link_info *info;
|
||
bfd *input_bfd;
|
||
asection *input_section;
|
||
bfd_byte *contents;
|
||
Elf_Internal_Rela *relocs;
|
||
Elf_Internal_Sym *local_syms;
|
||
asection **local_sections;
|
||
{
|
||
bfd *dynobj;
|
||
Elf_Internal_Shdr *symtab_hdr;
|
||
struct elf_link_hash_entry **sym_hashes;
|
||
bfd_vma *local_got_offsets;
|
||
asection *sgot;
|
||
asection *splt;
|
||
asection *sreloc;
|
||
Elf_Internal_Rela *rela;
|
||
Elf_Internal_Rela *relend;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
|
||
sym_hashes = elf_sym_hashes (input_bfd);
|
||
local_got_offsets = elf_local_got_offsets (input_bfd);
|
||
|
||
sreloc = splt = sgot = NULL;
|
||
if (dynobj != NULL)
|
||
{
|
||
splt = bfd_get_section_by_name (dynobj, ".plt");
|
||
sgot = bfd_get_section_by_name (dynobj, ".got");
|
||
}
|
||
|
||
rela = relocs;
|
||
relend = relocs + input_section->reloc_count;
|
||
for (; rela < relend; rela++)
|
||
{
|
||
int r_type;
|
||
reloc_howto_type *howto;
|
||
unsigned long r_symndx;
|
||
struct elf_link_hash_entry *h;
|
||
Elf_Internal_Sym *sym;
|
||
asection *sec;
|
||
bfd_vma relocation;
|
||
bfd_reloc_status_type r;
|
||
unsigned int indx;
|
||
|
||
r_type = ELF64_R_TYPE (rela->r_info);
|
||
if (r_type == (int) R_X86_64_GNU_VTINHERIT
|
||
|| r_type == (int) R_X86_64_GNU_VTENTRY)
|
||
continue;
|
||
|
||
if ((indx = (unsigned) r_type) >= R_X86_64_max)
|
||
{
|
||
bfd_set_error (bfd_error_bad_value);
|
||
return false;
|
||
}
|
||
howto = x86_64_elf_howto_table + indx;
|
||
|
||
r_symndx = ELF64_R_SYM (rela->r_info);
|
||
|
||
if (info->relocateable)
|
||
{
|
||
/* This is a relocateable link. We don't have to change
|
||
anything, unless the reloc is against a section symbol,
|
||
in which case we have to adjust according to where the
|
||
section symbol winds up in the output section. */
|
||
if (r_symndx < symtab_hdr->sh_info)
|
||
{
|
||
sym = local_syms + r_symndx;
|
||
if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
|
||
{
|
||
sec = local_sections[r_symndx];
|
||
rela->r_addend += sec->output_offset + sym->st_value;
|
||
}
|
||
}
|
||
|
||
continue;
|
||
}
|
||
|
||
/* This is a final link. */
|
||
h = NULL;
|
||
sym = NULL;
|
||
sec = NULL;
|
||
if (r_symndx < symtab_hdr->sh_info)
|
||
{
|
||
sym = local_syms + r_symndx;
|
||
sec = local_sections[r_symndx];
|
||
relocation = (sec->output_section->vma
|
||
+ sec->output_offset
|
||
+ sym->st_value);
|
||
}
|
||
else
|
||
{
|
||
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
|
||
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;
|
||
if (h->root.type == bfd_link_hash_defined
|
||
|| h->root.type == bfd_link_hash_defweak)
|
||
{
|
||
sec = h->root.u.def.section;
|
||
if ((r_type == R_X86_64_PLT32
|
||
&& splt != NULL
|
||
&& h->plt.offset != (bfd_vma) -1)
|
||
|| ((r_type == R_X86_64_GOT32 || r_type == R_X86_64_GOTPCREL)
|
||
&& elf_hash_table (info)->dynamic_sections_created
|
||
&& (!info->shared
|
||
|| (! info->symbolic && h->dynindx != -1)
|
||
|| (h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_DEF_REGULAR) == 0))
|
||
|| (info->shared
|
||
&& ((! info->symbolic && h->dynindx != -1)
|
||
|| (h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_DEF_REGULAR) == 0)
|
||
&& (r_type == R_X86_64_8
|
||
|| r_type == R_X86_64_16
|
||
|| r_type == R_X86_64_32
|
||
|| r_type == R_X86_64_64
|
||
|| r_type == R_X86_64_PC8
|
||
|| r_type == R_X86_64_PC16
|
||
|| r_type == R_X86_64_PC32)
|
||
&& ((input_section->flags & SEC_ALLOC) != 0
|
||
/* DWARF will emit R_X86_64_32 relocations in its
|
||
sections against symbols defined externally
|
||
in shared libraries. We can't do anything
|
||
with them here. */
|
||
|| ((input_section->flags & SEC_DEBUGGING) != 0
|
||
&& (h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_DEF_DYNAMIC) != 0))))
|
||
{
|
||
/* In these cases, we don't need the relocation
|
||
value. We check specially because in some
|
||
obscure cases sec->output_section will be NULL. */
|
||
relocation = 0;
|
||
}
|
||
else if (sec->output_section == NULL)
|
||
{
|
||
(*_bfd_error_handler)
|
||
(_("%s: warning: unresolvable relocation against symbol `%s' from %s section"),
|
||
bfd_get_filename (input_bfd), h->root.root.string,
|
||
bfd_get_section_name (input_bfd, input_section));
|
||
relocation = 0;
|
||
}
|
||
else
|
||
relocation = (h->root.u.def.value
|
||
+ sec->output_section->vma
|
||
+ sec->output_offset);
|
||
}
|
||
else if (h->root.type == bfd_link_hash_undefweak)
|
||
relocation = 0;
|
||
else if (info->shared && !info->symbolic && !info->no_undefined
|
||
&& ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
|
||
relocation = 0;
|
||
else
|
||
{
|
||
if (! ((*info->callbacks->undefined_symbol)
|
||
(info, h->root.root.string, input_bfd,
|
||
input_section, rela->r_offset,
|
||
(!info->shared || info->no_undefined
|
||
|| ELF_ST_VISIBILITY (h->other)))))
|
||
return false;
|
||
relocation = 0;
|
||
}
|
||
}
|
||
|
||
/* When generating a shared object, the relocations handled here are
|
||
copied into the output file to be resolved at run time. */
|
||
switch (r_type)
|
||
{
|
||
case R_X86_64_GOT32:
|
||
/* Relocation is to the entry for this symbol in the global
|
||
offset table. */
|
||
case R_X86_64_GOTPCREL:
|
||
/* Use global offset table as symbol value. */
|
||
BFD_ASSERT (sgot != NULL);
|
||
|
||
if (h != NULL)
|
||
{
|
||
bfd_vma off = h->got.offset;
|
||
BFD_ASSERT (off != (bfd_vma) -1);
|
||
|
||
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)))
|
||
{
|
||
/* This is actually a static link, or it is a -Bsymbolic
|
||
link and the symbol is defined locally, or the symbol
|
||
was forced to be local because of a version file. We
|
||
must initialize this entry in the global offset table.
|
||
Since the offset must always be a multiple of 8, we
|
||
use the least significant bit to record whether we
|
||
have initialized it already.
|
||
|
||
When doing a dynamic link, we create a .rela.got
|
||
relocation entry to initialize the value. This is
|
||
done in the finish_dynamic_symbol routine. */
|
||
if ((off & 1) != 0)
|
||
off &= ~1;
|
||
else
|
||
{
|
||
bfd_put_64 (output_bfd, relocation,
|
||
sgot->contents + off);
|
||
h->got.offset |= 1;
|
||
}
|
||
}
|
||
if (r_type == R_X86_64_GOTPCREL)
|
||
relocation = sgot->output_section->vma + sgot->output_offset + off;
|
||
else
|
||
relocation = sgot->output_offset + off;
|
||
}
|
||
else
|
||
{
|
||
bfd_vma off;
|
||
|
||
BFD_ASSERT (local_got_offsets != NULL
|
||
&& local_got_offsets[r_symndx] != (bfd_vma) -1);
|
||
|
||
off = local_got_offsets[r_symndx];
|
||
|
||
/* The offset must always be a multiple of 8. We use
|
||
the least significant bit to record whether we have
|
||
already generated the necessary reloc. */
|
||
if ((off & 1) != 0)
|
||
off &= ~1;
|
||
else
|
||
{
|
||
bfd_put_64 (output_bfd, relocation, sgot->contents + off);
|
||
|
||
if (info->shared)
|
||
{
|
||
asection *srelgot;
|
||
Elf_Internal_Rela outrel;
|
||
|
||
/* We need to generate a R_X86_64_RELATIVE reloc
|
||
for the dynamic linker. */
|
||
srelgot = bfd_get_section_by_name (dynobj, ".rela.got");
|
||
BFD_ASSERT (srelgot != NULL);
|
||
|
||
outrel.r_offset = (sgot->output_section->vma
|
||
+ sgot->output_offset
|
||
+ off);
|
||
outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
|
||
outrel.r_addend = relocation;
|
||
bfd_elf64_swap_reloca_out (output_bfd, &outrel,
|
||
(((Elf64_External_Rela *)
|
||
srelgot->contents)
|
||
+ srelgot->reloc_count));
|
||
++srelgot->reloc_count;
|
||
}
|
||
|
||
local_got_offsets[r_symndx] |= 1;
|
||
}
|
||
|
||
if (r_type == R_X86_64_GOTPCREL)
|
||
relocation = sgot->output_section->vma + sgot->output_offset + off;
|
||
else
|
||
relocation = sgot->output_offset + off;
|
||
}
|
||
|
||
break;
|
||
|
||
case R_X86_64_PLT32:
|
||
/* Relocation is to the entry for this symbol in the
|
||
procedure linkage table. */
|
||
|
||
/* 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 || splt == NULL)
|
||
{
|
||
/* We didn't make a PLT entry for this symbol. This
|
||
happens when statically linking PIC code, or when
|
||
using -Bsymbolic. */
|
||
break;
|
||
}
|
||
|
||
relocation = (splt->output_section->vma
|
||
+ splt->output_offset
|
||
+ h->plt.offset);
|
||
break;
|
||
|
||
case R_X86_64_PC8:
|
||
case R_X86_64_PC16:
|
||
case R_X86_64_PC32:
|
||
if (h == NULL || h->dynindx == -1
|
||
|| (info->symbolic
|
||
&& h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
|
||
break;
|
||
/* Fall through. */
|
||
case R_X86_64_8:
|
||
case R_X86_64_16:
|
||
case R_X86_64_32:
|
||
case R_X86_64_64:
|
||
/* FIXME: The ABI says the linker should make sure the value is
|
||
the same when it's zeroextended to 64 bit. */
|
||
if (info->shared && (input_section->flags & SEC_ALLOC) != 0)
|
||
{
|
||
Elf_Internal_Rela outrel;
|
||
boolean skip, relocate;
|
||
|
||
/* When generating a shared object, these relocations
|
||
are copied into the output file to be resolved at run
|
||
time. */
|
||
|
||
if (sreloc == NULL)
|
||
{
|
||
const char *name;
|
||
|
||
name = (bfd_elf_string_from_elf_section
|
||
(input_bfd,
|
||
elf_elfheader (input_bfd)->e_shstrndx,
|
||
elf_section_data (input_section)->rel_hdr.sh_name));
|
||
if (name == NULL)
|
||
return false;
|
||
|
||
BFD_ASSERT (strncmp (name, ".rela", 5) == 0
|
||
&& strcmp (bfd_get_section_name (input_bfd,
|
||
input_section),
|
||
name + 5) == 0);
|
||
|
||
sreloc = bfd_get_section_by_name (dynobj, name);
|
||
BFD_ASSERT (sreloc != NULL);
|
||
}
|
||
|
||
skip = false;
|
||
|
||
if (elf_section_data (input_section)->stab_info == NULL)
|
||
outrel.r_offset = rela->r_offset;
|
||
else
|
||
{
|
||
bfd_vma off;
|
||
|
||
off = (_bfd_stab_section_offset
|
||
(output_bfd, &elf_hash_table (info)->stab_info,
|
||
input_section,
|
||
&elf_section_data (input_section)->stab_info,
|
||
rela->r_offset));
|
||
if (off == (bfd_vma) -1)
|
||
skip = true;
|
||
outrel.r_offset = off;
|
||
}
|
||
|
||
outrel.r_offset += (input_section->output_section->vma
|
||
+ input_section->output_offset);
|
||
|
||
if (skip)
|
||
{
|
||
memset (&outrel, 0, sizeof outrel);
|
||
relocate = false;
|
||
}
|
||
/* h->dynindx may be -1 if this symbol was marked to
|
||
become local. */
|
||
else if (h != NULL
|
||
&& ((! info->symbolic && h->dynindx != -1)
|
||
|| (h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_DEF_REGULAR) == 0))
|
||
{
|
||
BFD_ASSERT (h->dynindx != -1);
|
||
relocate = false;
|
||
outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
|
||
outrel.r_addend = relocation + rela->r_addend;
|
||
}
|
||
else
|
||
{
|
||
if (r_type == R_X86_64_64)
|
||
{
|
||
relocate = true;
|
||
outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
|
||
outrel.r_addend = relocation + rela->r_addend;
|
||
}
|
||
else
|
||
{
|
||
long indx;
|
||
|
||
if (h == NULL)
|
||
sec = local_sections[r_symndx];
|
||
else
|
||
{
|
||
BFD_ASSERT (h->root.type == bfd_link_hash_defined
|
||
|| (h->root.type
|
||
== bfd_link_hash_defweak));
|
||
sec = h->root.u.def.section;
|
||
}
|
||
if (sec != NULL && bfd_is_abs_section (sec))
|
||
indx = 0;
|
||
else if (sec == NULL || sec->owner == NULL)
|
||
{
|
||
bfd_set_error (bfd_error_bad_value);
|
||
return false;
|
||
}
|
||
else
|
||
{
|
||
asection *osec;
|
||
|
||
osec = sec->output_section;
|
||
indx = elf_section_data (osec)->dynindx;
|
||
BFD_ASSERT (indx > 0);
|
||
}
|
||
|
||
relocate = false;
|
||
outrel.r_info = ELF64_R_INFO (indx, r_type);
|
||
outrel.r_addend = relocation + rela->r_addend;
|
||
}
|
||
|
||
}
|
||
|
||
bfd_elf64_swap_reloca_out (output_bfd, &outrel,
|
||
(((Elf64_External_Rela *)
|
||
sreloc->contents)
|
||
+ sreloc->reloc_count));
|
||
++sreloc->reloc_count;
|
||
|
||
/* If this reloc is against an external symbol, we do
|
||
not want to fiddle with the addend. Otherwise, we
|
||
need to include the symbol value so that it becomes
|
||
an addend for the dynamic reloc. */
|
||
if (! relocate)
|
||
continue;
|
||
}
|
||
|
||
break;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
r = _bfd_final_link_relocate (howto, input_bfd, input_section,
|
||
contents, rela->r_offset,
|
||
relocation, rela->r_addend);
|
||
|
||
if (r != bfd_reloc_ok)
|
||
{
|
||
switch (r)
|
||
{
|
||
default:
|
||
case bfd_reloc_outofrange:
|
||
abort ();
|
||
case bfd_reloc_overflow:
|
||
{
|
||
const char *name;
|
||
|
||
if (h != NULL)
|
||
name = h->root.root.string;
|
||
else
|
||
{
|
||
name = bfd_elf_string_from_elf_section (input_bfd,
|
||
symtab_hdr->sh_link,
|
||
sym->st_name);
|
||
if (name == NULL)
|
||
return false;
|
||
if (*name == '\0')
|
||
name = bfd_section_name (input_bfd, sec);
|
||
}
|
||
if (! ((*info->callbacks->reloc_overflow)
|
||
(info, name, howto->name, (bfd_vma) 0,
|
||
input_bfd, input_section, rela->r_offset)))
|
||
return false;
|
||
}
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Finish up dynamic symbol handling. We set the contents of various
|
||
dynamic sections here. */
|
||
|
||
static boolean
|
||
elf64_x86_64_finish_dynamic_symbol (output_bfd, info, h, sym)
|
||
bfd *output_bfd;
|
||
struct bfd_link_info *info;
|
||
struct elf_link_hash_entry *h;
|
||
Elf_Internal_Sym *sym;
|
||
{
|
||
bfd *dynobj;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
|
||
if (h->plt.offset != (bfd_vma) -1)
|
||
{
|
||
asection *splt;
|
||
asection *sgot;
|
||
asection *srela;
|
||
bfd_vma plt_index;
|
||
bfd_vma got_offset;
|
||
Elf_Internal_Rela rela;
|
||
|
||
/* This symbol has an entry in the procedure linkage table. Set
|
||
it up. */
|
||
|
||
BFD_ASSERT (h->dynindx != -1);
|
||
|
||
splt = bfd_get_section_by_name (dynobj, ".plt");
|
||
sgot = bfd_get_section_by_name (dynobj, ".got.plt");
|
||
srela = bfd_get_section_by_name (dynobj, ".rela.plt");
|
||
BFD_ASSERT (splt != NULL && sgot != NULL && srela != NULL);
|
||
|
||
/* Get the index in the procedure linkage table which
|
||
corresponds to this symbol. This is the index of this symbol
|
||
in all the symbols for which we are making plt entries. The
|
||
first entry in the procedure linkage table is reserved. */
|
||
plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
|
||
|
||
/* Get the offset into the .got table of the entry that
|
||
corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
|
||
bytes. The first three are reserved for the dynamic linker. */
|
||
got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
|
||
|
||
/* Fill in the entry in the procedure linkage table. */
|
||
memcpy (splt->contents + h->plt.offset, elf64_x86_64_plt_entry,
|
||
PLT_ENTRY_SIZE);
|
||
|
||
/* Insert the relocation positions of the plt section. The magic
|
||
numbers at the end of the statements are the positions of the
|
||
relocations in the plt section. */
|
||
/* Put offset for jmp *name@GOTPCREL(%rip), since the
|
||
instruction uses 6 bytes, subtract this value. */
|
||
bfd_put_32 (output_bfd,
|
||
(sgot->output_section->vma
|
||
+ sgot->output_offset
|
||
+ got_offset
|
||
- splt->output_section->vma
|
||
- splt->output_offset
|
||
- h->plt.offset
|
||
- 6),
|
||
splt->contents + h->plt.offset + 2);
|
||
/* Put relocation index. */
|
||
bfd_put_32 (output_bfd, plt_index,
|
||
splt->contents + h->plt.offset + 7);
|
||
/* Put offset for jmp .PLT0. */
|
||
bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
|
||
splt->contents + h->plt.offset + 12);
|
||
|
||
/* Fill in the entry in the global offset table, initially this
|
||
points to the pushq instruction in the PLT which is at offset 6. */
|
||
bfd_put_64 (output_bfd, (splt->output_section->vma + splt->output_offset
|
||
+ h->plt.offset + 6),
|
||
sgot->contents + got_offset);
|
||
|
||
/* Fill in the entry in the .rela.plt section. */
|
||
rela.r_offset = (sgot->output_section->vma
|
||
+ sgot->output_offset
|
||
+ got_offset);
|
||
rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
|
||
rela.r_addend = 0;
|
||
bfd_elf64_swap_reloca_out (output_bfd, &rela,
|
||
((Elf64_External_Rela *) srela->contents
|
||
+ plt_index));
|
||
|
||
if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
|
||
{
|
||
/* Mark the symbol as undefined, rather than as defined in
|
||
the .plt section. Leave the value alone. */
|
||
sym->st_shndx = SHN_UNDEF;
|
||
/* If the symbol is weak, we do need to clear the value.
|
||
Otherwise, the PLT entry would provide a definition for
|
||
the symbol even if the symbol wasn't defined anywhere,
|
||
and so the symbol would never be NULL. */
|
||
if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK)
|
||
== 0)
|
||
sym->st_value = 0;
|
||
}
|
||
}
|
||
|
||
if (h->got.offset != (bfd_vma) -1)
|
||
{
|
||
asection *sgot;
|
||
asection *srela;
|
||
Elf_Internal_Rela rela;
|
||
|
||
/* This symbol has an entry in the global offset table. Set it
|
||
up. */
|
||
|
||
sgot = bfd_get_section_by_name (dynobj, ".got");
|
||
srela = bfd_get_section_by_name (dynobj, ".rela.got");
|
||
BFD_ASSERT (sgot != NULL && srela != NULL);
|
||
|
||
rela.r_offset = (sgot->output_section->vma
|
||
+ sgot->output_offset
|
||
+ (h->got.offset &~ 1));
|
||
|
||
/* 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 (! elf_hash_table (info)->dynamic_sections_created
|
||
|| (info->shared
|
||
&& (info->symbolic || h->dynindx == -1)
|
||
&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
|
||
{
|
||
BFD_ASSERT((h->got.offset & 1) != 0);
|
||
rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
|
||
rela.r_addend = (h->root.u.def.value
|
||
+ h->root.u.def.section->output_section->vma
|
||
+ h->root.u.def.section->output_offset);
|
||
}
|
||
else
|
||
{
|
||
BFD_ASSERT((h->got.offset & 1) == 0);
|
||
bfd_put_64 (output_bfd, (bfd_vma) 0, sgot->contents + h->got.offset);
|
||
rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
|
||
rela.r_addend = 0;
|
||
}
|
||
|
||
bfd_elf64_swap_reloca_out (output_bfd, &rela,
|
||
((Elf64_External_Rela *) srela->contents
|
||
+ srela->reloc_count));
|
||
++srela->reloc_count;
|
||
}
|
||
|
||
if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
|
||
{
|
||
asection *s;
|
||
Elf_Internal_Rela rela;
|
||
|
||
/* This symbol needs a copy reloc. Set it up. */
|
||
|
||
BFD_ASSERT (h->dynindx != -1
|
||
&& (h->root.type == bfd_link_hash_defined
|
||
|| h->root.type == bfd_link_hash_defweak));
|
||
|
||
s = bfd_get_section_by_name (h->root.u.def.section->owner,
|
||
".rela.bss");
|
||
BFD_ASSERT (s != NULL);
|
||
|
||
rela.r_offset = (h->root.u.def.value
|
||
+ h->root.u.def.section->output_section->vma
|
||
+ h->root.u.def.section->output_offset);
|
||
rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
|
||
rela.r_addend = 0;
|
||
bfd_elf64_swap_reloca_out (output_bfd, &rela,
|
||
((Elf64_External_Rela *) s->contents
|
||
+ s->reloc_count));
|
||
++s->reloc_count;
|
||
}
|
||
|
||
/* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
|
||
if (strcmp (h->root.root.string, "_DYNAMIC") == 0
|
||
|| strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
|
||
sym->st_shndx = SHN_ABS;
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Finish up the dynamic sections. */
|
||
|
||
static boolean
|
||
elf64_x86_64_finish_dynamic_sections (output_bfd, info)
|
||
bfd *output_bfd;
|
||
struct bfd_link_info *info;
|
||
{
|
||
bfd *dynobj;
|
||
asection *sdyn;
|
||
asection *sgot;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
|
||
sgot = bfd_get_section_by_name (dynobj, ".got.plt");
|
||
BFD_ASSERT (sgot != NULL);
|
||
sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
|
||
|
||
if (elf_hash_table (info)->dynamic_sections_created)
|
||
{
|
||
asection *splt;
|
||
Elf64_External_Dyn *dyncon, *dynconend;
|
||
|
||
BFD_ASSERT (sdyn != NULL);
|
||
|
||
dyncon = (Elf64_External_Dyn *) sdyn->contents;
|
||
dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
|
||
for (; dyncon < dynconend; dyncon++)
|
||
{
|
||
Elf_Internal_Dyn dyn;
|
||
const char *name;
|
||
asection *s;
|
||
|
||
bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
|
||
|
||
switch (dyn.d_tag)
|
||
{
|
||
default:
|
||
continue;
|
||
|
||
case DT_PLTGOT:
|
||
name = ".got";
|
||
goto get_vma;
|
||
|
||
case DT_JMPREL:
|
||
name = ".rela.plt";
|
||
|
||
get_vma:
|
||
s = bfd_get_section_by_name (output_bfd, name);
|
||
BFD_ASSERT (s != NULL);
|
||
dyn.d_un.d_ptr = s->vma;
|
||
break;
|
||
|
||
case DT_RELASZ:
|
||
/* FIXME: This comment and code is from elf64-alpha.c: */
|
||
/* My interpretation of the TIS v1.1 ELF document indicates
|
||
that RELASZ should not include JMPREL. This is not what
|
||
the rest of the BFD does. It is, however, what the
|
||
glibc ld.so wants. Do this fixup here until we found
|
||
out who is right. */
|
||
s = bfd_get_section_by_name (output_bfd, ".rela.plt");
|
||
if (s)
|
||
{
|
||
/* Subtract JMPREL size from RELASZ. */
|
||
dyn.d_un.d_val -=
|
||
(s->_cooked_size ? s->_cooked_size : s->_raw_size);
|
||
}
|
||
break;
|
||
|
||
case DT_PLTRELSZ:
|
||
s = bfd_get_section_by_name (output_bfd, ".rela.plt");
|
||
BFD_ASSERT (s != NULL);
|
||
dyn.d_un.d_val =
|
||
(s->_cooked_size != 0 ? s->_cooked_size : s->_raw_size);
|
||
break;
|
||
}
|
||
bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
|
||
}
|
||
|
||
/* Initialize the contents of the .plt section. */
|
||
splt = bfd_get_section_by_name (dynobj, ".plt");
|
||
BFD_ASSERT (splt != NULL);
|
||
if (splt->_raw_size > 0)
|
||
{
|
||
/* Fill in the first entry in the procedure linkage table. */
|
||
memcpy (splt->contents, elf64_x86_64_plt0_entry, PLT_ENTRY_SIZE);
|
||
/* Add offset for pushq GOT+8(%rip), since the instruction
|
||
uses 6 bytes subtract this value. */
|
||
bfd_put_32 (output_bfd,
|
||
(sgot->output_section->vma
|
||
+ sgot->output_offset
|
||
+ 8
|
||
- splt->output_section->vma
|
||
- splt->output_offset
|
||
- 6),
|
||
splt->contents + 2);
|
||
/* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
|
||
the end of the instruction. */
|
||
bfd_put_32 (output_bfd,
|
||
(sgot->output_section->vma
|
||
+ sgot->output_offset
|
||
+ 16
|
||
- splt->output_section->vma
|
||
- splt->output_offset
|
||
- 12),
|
||
splt->contents + 8);
|
||
|
||
}
|
||
|
||
elf_section_data (splt->output_section)->this_hdr.sh_entsize =
|
||
PLT_ENTRY_SIZE;
|
||
}
|
||
|
||
/* Set the first entry in the global offset table to the address of
|
||
the dynamic section. */
|
||
if (sgot->_raw_size > 0)
|
||
{
|
||
if (sdyn == NULL)
|
||
bfd_put_64 (output_bfd, (bfd_vma) 0, sgot->contents);
|
||
else
|
||
bfd_put_64 (output_bfd,
|
||
sdyn->output_section->vma + sdyn->output_offset,
|
||
sgot->contents);
|
||
/* Write GOT[1] and GOT[2], needed for the dynamic linker. */
|
||
bfd_put_64 (output_bfd, (bfd_vma) 0, sgot->contents + GOT_ENTRY_SIZE);
|
||
bfd_put_64 (output_bfd, (bfd_vma) 0, sgot->contents + GOT_ENTRY_SIZE*2);
|
||
}
|
||
|
||
elf_section_data (sgot->output_section)->this_hdr.sh_entsize =
|
||
GOT_ENTRY_SIZE;
|
||
|
||
return true;
|
||
}
|
||
|
||
static enum elf_reloc_type_class
|
||
elf64_x86_64_reloc_type_class (type)
|
||
int type;
|
||
{
|
||
switch (type)
|
||
{
|
||
case R_X86_64_RELATIVE:
|
||
return reloc_class_relative;
|
||
case R_X86_64_JUMP_SLOT:
|
||
return reloc_class_plt;
|
||
case R_X86_64_COPY:
|
||
return reloc_class_copy;
|
||
default:
|
||
return reloc_class_normal;
|
||
}
|
||
}
|
||
|
||
#define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
|
||
#define TARGET_LITTLE_NAME "elf64-x86-64"
|
||
#define ELF_ARCH bfd_arch_i386
|
||
#define ELF_MACHINE_CODE EM_X86_64
|
||
#define ELF_MAXPAGESIZE 0x100000
|
||
|
||
#define elf_backend_can_gc_sections 1
|
||
#define elf_backend_want_got_plt 1
|
||
#define elf_backend_plt_readonly 1
|
||
#define elf_backend_want_plt_sym 0
|
||
#define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
|
||
#define elf_backend_plt_header_size PLT_ENTRY_SIZE
|
||
|
||
#define elf_info_to_howto elf64_x86_64_info_to_howto
|
||
|
||
#define bfd_elf64_bfd_final_link _bfd_elf64_gc_common_final_link
|
||
#define bfd_elf64_bfd_link_hash_table_create \
|
||
elf64_x86_64_link_hash_table_create
|
||
#define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
|
||
|
||
#define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
|
||
#define elf_backend_check_relocs elf64_x86_64_check_relocs
|
||
#define elf_backend_create_dynamic_sections _bfd_elf_create_dynamic_sections
|
||
#define elf_backend_finish_dynamic_sections \
|
||
elf64_x86_64_finish_dynamic_sections
|
||
#define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
|
||
#define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
|
||
#define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
|
||
#define elf_backend_relocate_section elf64_x86_64_relocate_section
|
||
#define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
|
||
#define elf_backend_object_p elf64_x86_64_elf_object_p
|
||
#define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
|
||
|
||
#include "elf64-target.h"
|