940 lines
31 KiB
C
940 lines
31 KiB
C
/* x86 specific support for ELF
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Copyright (C) 2017-2022 Free Software Foundation, Inc.
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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 3 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., 51 Franklin Street - Fifth Floor, Boston,
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MA 02110-1301, USA. */
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/* Don't generate unused section symbols. */
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#define TARGET_KEEP_UNUSED_SECTION_SYMBOLS false
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#include "sysdep.h"
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#include "bfd.h"
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#include "bfdlink.h"
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#include "libbfd.h"
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#include "elf-bfd.h"
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#include "hashtab.h"
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#include "elf-linker-x86.h"
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#include "elf/i386.h"
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#include "elf/x86-64.h"
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#define X86_64_PCREL_TYPE_P(TYPE) \
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((TYPE) == R_X86_64_PC8 \
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|| (TYPE) == R_X86_64_PC16 \
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|| (TYPE) == R_X86_64_PC32 \
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|| (TYPE) == R_X86_64_PC32_BND \
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|| (TYPE) == R_X86_64_PC64)
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#define I386_PCREL_TYPE_P(TYPE) ((TYPE) == R_386_PC32)
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#define X86_PCREL_TYPE_P(IS_X86_64, TYPE) \
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((IS_X86_64) ? X86_64_PCREL_TYPE_P (TYPE) : I386_PCREL_TYPE_P (TYPE))
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#define X86_64_SIZE_TYPE_P(TYPE) \
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((TYPE) == R_X86_64_SIZE32 || (TYPE) == R_X86_64_SIZE64)
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#define I386_SIZE_TYPE_P(TYPE) ((TYPE) == R_386_SIZE32)
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#define X86_SIZE_TYPE_P(IS_X86_64, TYPE) \
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((IS_X86_64) ? X86_64_SIZE_TYPE_P(TYPE) : I386_SIZE_TYPE_P (TYPE))
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#define X86_64_GOT_TYPE_P(TYPE) \
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((TYPE) == R_X86_64_GOTPCREL \
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|| (TYPE) == R_X86_64_GOTPCRELX \
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|| (TYPE) == R_X86_64_REX_GOTPCRELX \
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|| (TYPE) == R_X86_64_GOT32 \
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|| (TYPE) == R_X86_64_GOT64 \
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|| (TYPE) == R_X86_64_GOTPCREL64 \
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|| (TYPE) == R_X86_64_GOTPLT64)
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#define I386_GOT_TYPE_P(TYPE) \
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((TYPE) == R_386_GOT32 || (TYPE) == R_386_GOT32X)
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#define X86_GOT_TYPE_P(IS_X86_64, TYPE) \
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((IS_X86_64) ? X86_64_GOT_TYPE_P (TYPE) : I386_GOT_TYPE_P (TYPE))
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#define X86_64_RELATIVE_RELOC_TYPE_P(TYPE) \
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(X86_64_PCREL_TYPE_P (TYPE) \
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|| (TYPE) == R_X86_64_8 \
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|| (TYPE) == R_X86_64_16 \
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|| (TYPE) == R_X86_64_32 \
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|| (TYPE) == R_X86_64_32S \
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|| (TYPE) == R_X86_64_64)
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#define I386_RELATIVE_RELOC_TYPE_P(TYPE) \
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((TYPE) == R_386_32 || (TYPE) == R_386_PC32)
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#define X86_RELATIVE_RELOC_TYPE_P(IS_X86_64, TYPE) \
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((IS_X86_64) \
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? X86_64_RELATIVE_RELOC_TYPE_P (TYPE) \
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: I386_RELATIVE_RELOC_TYPE_P(TYPE))
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#define X86_64_NEED_DYNAMIC_RELOC_TYPE_P(TYPE) \
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(X86_64_SIZE_TYPE_P (TYPE) \
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|| X86_64_RELATIVE_RELOC_TYPE_P (TYPE))
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#define I386_NEED_DYNAMIC_RELOC_TYPE_P(TYPE) \
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(I386_SIZE_TYPE_P (TYPE) \
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|| I386_RELATIVE_RELOC_TYPE_P (TYPE) \
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|| (TYPE) == R_386_TLS_IE \
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|| (TYPE) == R_386_TLS_LE \
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|| (TYPE) == R_386_TLS_LE_32)
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#define X86_NEED_DYNAMIC_RELOC_TYPE_P(IS_X86_64, TYPE) \
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((IS_X86_64) \
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? X86_64_NEED_DYNAMIC_RELOC_TYPE_P (TYPE) \
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: I386_NEED_DYNAMIC_RELOC_TYPE_P (TYPE))
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#define X86_LOCAL_GOT_RELATIVE_RELOC_P(IS_X86_64, INFO, SYM) \
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(bfd_link_pic (INFO) \
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&& (!(IS_X86_64) || ((SYM) != NULL && (SYM)->st_shndx != SHN_ABS)))
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#define PLT_CIE_LENGTH 20
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#define PLT_FDE_LENGTH 36
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#define PLT_FDE_START_OFFSET 4 + PLT_CIE_LENGTH + 8
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#define PLT_FDE_LEN_OFFSET 4 + PLT_CIE_LENGTH + 12
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#define I386_PCREL_TYPE_P(TYPE) ((TYPE) == R_386_PC32)
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#define X86_64_PCREL_TYPE_P(TYPE) \
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((TYPE) == R_X86_64_PC8 \
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|| (TYPE) == R_X86_64_PC16 \
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|| (TYPE) == R_X86_64_PC32 \
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|| (TYPE) == R_X86_64_PC32_BND \
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|| (TYPE) == R_X86_64_PC64)
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#define ABI_64_P(abfd) \
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(get_elf_backend_data (abfd)->s->elfclass == ELFCLASS64)
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/* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
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copying dynamic variables from a shared lib into an app's dynbss
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section, and instead use a dynamic relocation to point into the
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shared lib. */
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#define ELIMINATE_COPY_RELOCS 1
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#define elf_x86_hash_table(p, id) \
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(is_elf_hash_table ((p)->hash) \
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&& elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) == (id) \
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? ((struct elf_x86_link_hash_table *) ((p)->hash)) : NULL)
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/* Will references to this symbol always be local in this object? */
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#define SYMBOL_REFERENCES_LOCAL_P(INFO, H) \
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_bfd_x86_elf_link_symbol_references_local ((INFO), (H))
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/* TRUE if an undefined weak symbol should be resolved to 0. Local
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undefined weak symbol is always resolved to 0. Reference to an
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undefined weak symbol is resolved to 0 in executable if undefined
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weak symbol should be resolved to 0 (zero_undefweak > 0). */
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#define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, EH) \
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((EH)->elf.root.type == bfd_link_hash_undefweak \
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&& (SYMBOL_REFERENCES_LOCAL_P ((INFO), &(EH)->elf) \
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|| (bfd_link_executable (INFO) \
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&& (EH)->zero_undefweak > 0)))
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/* Should copy relocation be generated for a symbol. Don't generate
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copy relocation against a protected symbol defined in a shared
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object. */
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#define SYMBOL_NO_COPYRELOC(INFO, EH) \
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((EH)->def_protected \
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&& ((EH)->elf.root.type == bfd_link_hash_defined \
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|| (EH)->elf.root.type == bfd_link_hash_defweak) \
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&& ((EH)->elf.root.u.def.section->owner->flags & DYNAMIC) != 0 \
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&& ((EH)->elf.root.u.def.section->flags & SEC_CODE) == 0)
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/* TRUE if dynamic relocation is needed. If we are creating a shared
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library, and this is a reloc against a global symbol, or a non PC
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relative reloc against a local symbol, then we need to copy the reloc
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into the shared library. However, if we are linking with -Bsymbolic,
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we do not need to copy a reloc against a global symbol which is
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defined in an object we are including in the link (i.e., DEF_REGULAR
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is set).
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If PCREL_PLT is true, don't generate dynamic relocation in PIE for
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PC-relative relocation against a dynamic function definition in data
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section when PLT address can be used.
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If on the other hand, we are creating an executable, we may need to
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keep relocations for symbols satisfied by a dynamic library if we
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manage to avoid copy relocs for the symbol.
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We also need to generate dynamic pointer relocation against
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STT_GNU_IFUNC symbol in the non-code section. */
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#define NEED_DYNAMIC_RELOCATION_P(IS_X86_64, INFO, PCREL_PLT, H, SEC, \
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R_TYPE, POINTER_TYPE) \
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((bfd_link_pic (INFO) \
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&& (! X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
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|| ((H) != NULL \
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&& (! (bfd_link_pie (INFO) \
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|| SYMBOLIC_BIND ((INFO), (H))) \
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|| (H)->root.type == bfd_link_hash_defweak \
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|| (!(bfd_link_pie (INFO) \
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&& (PCREL_PLT) \
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&& (H)->plt.refcount > 0 \
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&& ((SEC)->flags & SEC_CODE) == 0 \
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&& (H)->type == STT_FUNC \
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&& (H)->def_dynamic) \
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&& !(H)->def_regular))))) \
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|| ((H) != NULL \
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&& (H)->type == STT_GNU_IFUNC \
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&& (R_TYPE) == POINTER_TYPE \
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&& ((SEC)->flags & SEC_CODE) == 0) \
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|| (ELIMINATE_COPY_RELOCS \
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&& !bfd_link_pic (INFO) \
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&& (H) != NULL \
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&& ((H)->root.type == bfd_link_hash_defweak \
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|| !(H)->def_regular)))
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/* TRUE if dynamic relocation should be generated. Don't copy a
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pc-relative relocation into the output file if the symbol needs
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copy reloc or the symbol is undefined when building executable.
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Copy dynamic function pointer relocations. Don't generate dynamic
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relocations against resolved undefined weak symbols in PIE, except
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when PC32_RELOC is TRUE. Undefined weak symbol is bound locally
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when PIC is false. Don't generate dynamic relocations against
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non-preemptible absolute symbol. NB: rel_from_abs is set on symbols
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defined by linker scripts from "dot" (also SEGMENT_START or ORIGIN)
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outside of an output section statement, which will be converted from
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absolute to section-relative in set_sym_sections called from
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ldexp_finalize_syms after ldemul_finish. */
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#define GENERATE_DYNAMIC_RELOCATION_P(IS_X86_64, INFO, EH, R_TYPE, \
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SEC, NEED_COPY_RELOC_IN_PIE, \
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RESOLVED_TO_ZERO, PC32_RELOC) \
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((bfd_link_pic (INFO) \
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&& !(bfd_is_abs_section (SEC) \
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&& ((EH) == NULL \
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|| (EH)->elf.root.rel_from_abs == 0) \
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&& ((EH) == NULL \
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|| SYMBOL_REFERENCES_LOCAL (INFO, &(EH)->elf))) \
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&& !(NEED_COPY_RELOC_IN_PIE) \
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&& ((EH) == NULL \
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|| ((ELF_ST_VISIBILITY ((EH)->elf.other) == STV_DEFAULT \
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&& (!(RESOLVED_TO_ZERO) || PC32_RELOC)) \
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|| (EH)->elf.root.type != bfd_link_hash_undefweak)) \
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&& ((!X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
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&& !X86_SIZE_TYPE_P (IS_X86_64, R_TYPE)) \
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|| ! SYMBOL_CALLS_LOCAL ((INFO), \
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(struct elf_link_hash_entry *) (EH)))) \
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|| (ELIMINATE_COPY_RELOCS \
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&& !bfd_link_pic (INFO) \
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&& (EH) != NULL \
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&& (EH)->elf.dynindx != -1 \
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&& (!(EH)->elf.non_got_ref \
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|| ((EH)->elf.root.type == bfd_link_hash_undefweak \
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&& !(RESOLVED_TO_ZERO))) \
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&& (((EH)->elf.def_dynamic && !(EH)->elf.def_regular) \
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|| (EH)->elf.root.type == bfd_link_hash_undefined)))
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/* TRUE if this input relocation should be copied to output. H->dynindx
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may be -1 if this symbol was marked to become local. */
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#define COPY_INPUT_RELOC_P(IS_X86_64, INFO, H, R_TYPE) \
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((H) != NULL \
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&& (H)->dynindx != -1 \
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&& (X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
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|| !(bfd_link_executable (INFO) || SYMBOLIC_BIND ((INFO), (H))) \
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|| !(H)->def_regular))
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/* TRUE if this is actually a static link, or it is a -Bsymbolic link
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and the symbol is defined locally, or the symbol was forced to be
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local because of a version file. */
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#define RESOLVED_LOCALLY_P(INFO, H, HTAB) \
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(!WILL_CALL_FINISH_DYNAMIC_SYMBOL ((HTAB)->elf.dynamic_sections_created, \
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bfd_link_pic (INFO), (H)) \
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|| (bfd_link_pic (INFO) \
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&& SYMBOL_REFERENCES_LOCAL_P ((INFO), (H))) \
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|| (ELF_ST_VISIBILITY ((H)->other) \
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&& (H)->root.type == bfd_link_hash_undefweak))
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/* TRUE if this symbol isn't defined by a shared object. */
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#define SYMBOL_DEFINED_NON_SHARED_P(H) \
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((H)->def_regular \
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|| (H)->root.linker_def \
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|| (H)->root.ldscript_def \
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|| ((struct elf_x86_link_hash_entry *) (H))->linker_def \
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|| ELF_COMMON_DEF_P (H))
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/* Return TRUE if the symbol described by a linker hash entry H is
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going to be absolute. Similar to bfd_is_abs_symbol, but excluding
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all linker-script defined symbols. */
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#define ABS_SYMBOL_P(H) \
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(bfd_is_abs_symbol (&(H)->root) && !(H)->root.ldscript_def)
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/* TRUE if relative relocation should be generated. GOT reference to
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global symbol in PIC will lead to dynamic symbol. It becomes a
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problem when "time" or "times" is defined as a variable in an
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executable, clashing with functions of the same name in libc. If a
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symbol isn't undefined weak symbol, don't make it dynamic in PIC and
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generate relative relocation. Don't generate relative relocation
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against non-preemptible absolute symbol. */
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#define GENERATE_RELATIVE_RELOC_P(INFO, H) \
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((H)->dynindx == -1 \
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&& !(H)->forced_local \
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&& (H)->root.type != bfd_link_hash_undefweak \
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&& bfd_link_pic (INFO) \
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&& !ABS_SYMBOL_P (H))
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/* TRUE if this is a pointer reference to a local IFUNC. */
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#define POINTER_LOCAL_IFUNC_P(INFO, H) \
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((H)->dynindx == -1 \
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|| (H)->forced_local \
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|| bfd_link_executable (INFO))
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/* TRUE if this is a PLT reference to a local IFUNC. */
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#define PLT_LOCAL_IFUNC_P(INFO, H) \
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((H)->dynindx == -1 \
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|| ((bfd_link_executable (INFO) \
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|| ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT) \
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&& (H)->def_regular \
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&& (H)->type == STT_GNU_IFUNC))
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/* TRUE if TLS IE->LE transition is OK. */
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#define TLS_TRANSITION_IE_TO_LE_P(INFO, H, TLS_TYPE) \
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(bfd_link_executable (INFO) \
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&& (H) != NULL \
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&& (H)->dynindx == -1 \
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&& (TLS_TYPE & GOT_TLS_IE))
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/* Verify that the symbol has an entry in the procedure linkage table. */
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#define VERIFY_PLT_ENTRY(INFO, H, PLT, GOTPLT, RELPLT, LOCAL_UNDEFWEAK) \
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do \
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{ \
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if (((H)->dynindx == -1 \
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&& !LOCAL_UNDEFWEAK \
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&& !(((H)->forced_local || bfd_link_executable (INFO)) \
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&& (H)->def_regular \
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&& (H)->type == STT_GNU_IFUNC)) \
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|| (PLT) == NULL \
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|| (GOTPLT) == NULL \
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|| (RELPLT) == NULL) \
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abort (); \
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} \
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while (0);
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/* Verify that the symbol supports copy relocation. */
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#define VERIFY_COPY_RELOC(H, HTAB) \
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do \
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{ \
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if ((H)->dynindx == -1 \
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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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|| (HTAB)->elf.srelbss == NULL \
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|| (HTAB)->elf.sreldynrelro == NULL) \
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abort (); \
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} \
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while (0);
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/* x86 ELF linker hash entry. */
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struct elf_x86_link_hash_entry
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{
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struct elf_link_hash_entry elf;
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unsigned char tls_type;
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/* Bit 0: Symbol has no GOT nor PLT relocations.
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Bit 1: Symbol has non-GOT/non-PLT relocations in text sections.
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zero_undefweak is initialized to 1 and undefined weak symbol
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should be resolved to 0 if zero_undefweak > 0. */
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unsigned int zero_undefweak : 2;
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/* Don't call finish_dynamic_symbol on this symbol. */
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unsigned int no_finish_dynamic_symbol : 1;
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/* R_*_RELATIVE relocation in GOT for this symbol has been
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processed. */
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unsigned int got_relative_reloc_done : 1;
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/* TRUE if symbol is __tls_get_addr. */
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unsigned int tls_get_addr : 1;
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/* TRUE if symbol is defined as a protected symbol. */
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unsigned int def_protected : 1;
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/* 0: Symbol references are unknown.
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1: Symbol references aren't local.
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2: Symbol references are local.
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*/
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unsigned int local_ref : 2;
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/* TRUE if symbol is defined by linker. */
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unsigned int linker_def : 1;
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/* TRUE if symbol is referenced by a non-GOT/non-PLT relocation in a
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relocatable object file without indirect external access marker. */
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unsigned int non_got_ref_without_indirect_extern_access : 1;
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/* TRUE if symbol is referenced by R_386_GOTOFF relocation. This is
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only used by i386. */
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unsigned int gotoff_ref : 1;
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/* TRUE if a weak symbol with a real definition needs a copy reloc.
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When there is a weak symbol with a real definition, the processor
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independent code will have arranged for us to see the real
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definition first. We need to copy the needs_copy bit from the
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real definition and check it when allowing copy reloc in PIE. This
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is only used by x86-64. */
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unsigned int needs_copy : 1;
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/* Information about the GOT PLT entry. Filled when there are both
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GOT and PLT relocations against the same function. */
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union gotplt_union plt_got;
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/* Information about the second PLT entry. */
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union gotplt_union plt_second;
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/* Offset of the GOTPLT entry reserved for the TLS descriptor,
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starting at the end of the jump table. */
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bfd_vma tlsdesc_got;
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};
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struct elf_x86_lazy_plt_layout
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{
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/* The first entry in a lazy procedure linkage table looks like this. */
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const bfd_byte *plt0_entry;
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unsigned int plt0_entry_size; /* Size of PLT0 entry. */
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/* Later entries in a lazy procedure linkage table look like this. */
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const bfd_byte *plt_entry;
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unsigned int plt_entry_size; /* Size of each PLT entry. */
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/* The TLSDESC entry in a lazy procedure linkage table looks like
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this. This is for x86-64 only. */
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const bfd_byte *plt_tlsdesc_entry;
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unsigned int plt_tlsdesc_entry_size; /* Size of TLSDESC entry. */
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|
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/* Offsets into the TLSDESC entry that are to be replaced with
|
|
GOT+8 and GOT+TDG. These are for x86-64 only. */
|
|
unsigned int plt_tlsdesc_got1_offset;
|
|
unsigned int plt_tlsdesc_got2_offset;
|
|
|
|
/* Offset of the end of the PC-relative instructions containing
|
|
plt_tlsdesc_got1_offset and plt_tlsdesc_got2_offset. These
|
|
are for x86-64 only. */
|
|
unsigned int plt_tlsdesc_got1_insn_end;
|
|
unsigned int plt_tlsdesc_got2_insn_end;
|
|
|
|
/* Offsets into plt0_entry that are to be replaced with GOT[1] and
|
|
GOT[2]. */
|
|
unsigned int plt0_got1_offset;
|
|
unsigned int plt0_got2_offset;
|
|
|
|
/* Offset of the end of the PC-relative instruction containing
|
|
plt0_got2_offset. This is for x86-64 only. */
|
|
unsigned int plt0_got2_insn_end;
|
|
|
|
/* Offsets into plt_entry that are to be replaced with... */
|
|
unsigned int plt_got_offset; /* ... address of this symbol in .got. */
|
|
unsigned int plt_reloc_offset; /* ... offset into relocation table. */
|
|
unsigned int plt_plt_offset; /* ... offset to start of .plt. */
|
|
|
|
/* Length of the PC-relative instruction containing plt_got_offset.
|
|
This is used for x86-64 only. */
|
|
unsigned int plt_got_insn_size;
|
|
|
|
/* Offset of the end of the PC-relative jump to plt0_entry. This is
|
|
used for x86-64 only. */
|
|
unsigned int plt_plt_insn_end;
|
|
|
|
/* Offset into plt_entry where the initial value of the GOT entry
|
|
points. */
|
|
unsigned int plt_lazy_offset;
|
|
|
|
/* The first entry in a PIC lazy procedure linkage table looks like
|
|
this. */
|
|
const bfd_byte *pic_plt0_entry;
|
|
|
|
/* Subsequent entries in a PIC lazy procedure linkage table look
|
|
like this. */
|
|
const bfd_byte *pic_plt_entry;
|
|
|
|
/* .eh_frame covering the lazy .plt section. */
|
|
const bfd_byte *eh_frame_plt;
|
|
unsigned int eh_frame_plt_size;
|
|
};
|
|
|
|
struct elf_x86_non_lazy_plt_layout
|
|
{
|
|
/* Entries in a non-lazy procedure linkage table look like this. */
|
|
const bfd_byte *plt_entry;
|
|
/* Entries in a PIC non-lazy procedure linkage table look like this.
|
|
This is only used for i386 where absolute PLT and PIC PLT are
|
|
different. */
|
|
const bfd_byte *pic_plt_entry;
|
|
|
|
unsigned int plt_entry_size; /* Size of each PLT entry. */
|
|
|
|
/* Offsets into plt_entry that are to be replaced with... */
|
|
unsigned int plt_got_offset; /* ... address of this symbol in .got. */
|
|
|
|
/* Length of the PC-relative instruction containing plt_got_offset.
|
|
This is used for x86-64 only. */
|
|
unsigned int plt_got_insn_size;
|
|
|
|
/* .eh_frame covering the non-lazy .plt section. */
|
|
const bfd_byte *eh_frame_plt;
|
|
unsigned int eh_frame_plt_size;
|
|
};
|
|
|
|
struct elf_x86_plt_layout
|
|
{
|
|
/* The first entry in a lazy procedure linkage table looks like this. */
|
|
const bfd_byte *plt0_entry;
|
|
/* Entries in a procedure linkage table look like this. */
|
|
const bfd_byte *plt_entry;
|
|
unsigned int plt_entry_size; /* Size of each PLT entry. */
|
|
|
|
/* 1 has PLT0. */
|
|
unsigned int has_plt0;
|
|
|
|
/* Offsets into plt_entry that are to be replaced with... */
|
|
unsigned int plt_got_offset; /* ... address of this symbol in .got. */
|
|
|
|
/* Length of the PC-relative instruction containing plt_got_offset.
|
|
This is only used for x86-64. */
|
|
unsigned int plt_got_insn_size;
|
|
|
|
/* Alignment of the .iplt section. */
|
|
unsigned int iplt_alignment;
|
|
|
|
/* .eh_frame covering the .plt section. */
|
|
const bfd_byte *eh_frame_plt;
|
|
unsigned int eh_frame_plt_size;
|
|
};
|
|
|
|
/* Values in tls_type of x86 ELF linker hash entry. */
|
|
#define GOT_UNKNOWN 0
|
|
#define GOT_NORMAL 1
|
|
#define GOT_TLS_GD 2
|
|
#define GOT_TLS_IE 4
|
|
#define GOT_TLS_IE_POS 5
|
|
#define GOT_TLS_IE_NEG 6
|
|
#define GOT_TLS_IE_BOTH 7
|
|
#define GOT_TLS_GDESC 8
|
|
#define GOT_ABS 9
|
|
#define GOT_TLS_GD_BOTH_P(type) \
|
|
((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
|
|
#define GOT_TLS_GD_P(type) \
|
|
((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
|
|
#define GOT_TLS_GDESC_P(type) \
|
|
((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
|
|
#define GOT_TLS_GD_ANY_P(type) \
|
|
(GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
|
|
|
|
#define elf_x86_hash_entry(ent) \
|
|
((struct elf_x86_link_hash_entry *)(ent))
|
|
|
|
/* Information of an input relocation used to compute its contribution
|
|
to the DT_RELR section size. */
|
|
|
|
struct elf_x86_relative_reloc_record
|
|
{
|
|
/* The original relocation info. */
|
|
Elf_Internal_Rela rel;
|
|
/* The input or the GOT section where the relocation is applied. */
|
|
asection *sec;
|
|
/* Local symbol info. NULL for global symbol. */
|
|
Elf_Internal_Sym *sym;
|
|
union
|
|
{
|
|
/* Section where the local symbol is defined. */
|
|
asection *sym_sec;
|
|
/* Global symbol hash. */
|
|
struct elf_link_hash_entry *h;
|
|
} u;
|
|
/* The offset into the output section where the relative relocation
|
|
will be applied at run-time. */
|
|
bfd_vma offset;
|
|
/* The run-time address. */
|
|
bfd_vma address;
|
|
};
|
|
|
|
struct elf_x86_relative_reloc_data
|
|
{
|
|
bfd_size_type count;
|
|
bfd_size_type size;
|
|
struct elf_x86_relative_reloc_record *data;
|
|
};
|
|
|
|
/* DT_RELR bitmap. */
|
|
struct elf_dt_relr_bitmap
|
|
{
|
|
bfd_size_type count;
|
|
bfd_size_type size;
|
|
union
|
|
{
|
|
/* 32-bit bitmap. */
|
|
uint32_t *elf32;
|
|
/* 64-bit bitmap. */
|
|
uint64_t *elf64;
|
|
} u;
|
|
};
|
|
|
|
/* x86 ELF linker hash table. */
|
|
|
|
struct elf_x86_link_hash_table
|
|
{
|
|
struct elf_link_hash_table elf;
|
|
|
|
/* Short-cuts to get to dynamic linker sections. */
|
|
asection *interp;
|
|
asection *plt_eh_frame;
|
|
asection *plt_second;
|
|
asection *plt_second_eh_frame;
|
|
asection *plt_got;
|
|
asection *plt_got_eh_frame;
|
|
|
|
/* Parameters describing PLT generation, lazy or non-lazy. */
|
|
struct elf_x86_plt_layout plt;
|
|
|
|
/* Parameters describing lazy PLT generation. */
|
|
const struct elf_x86_lazy_plt_layout *lazy_plt;
|
|
|
|
/* Parameters describing non-lazy PLT generation. */
|
|
const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
|
|
|
|
union
|
|
{
|
|
bfd_signed_vma refcount;
|
|
bfd_vma offset;
|
|
} tls_ld_or_ldm_got;
|
|
|
|
/* The amount of space used by the jump slots in the GOT. */
|
|
bfd_vma sgotplt_jump_table_size;
|
|
|
|
/* _TLS_MODULE_BASE_ symbol. */
|
|
struct bfd_link_hash_entry *tls_module_base;
|
|
|
|
/* Used by local STT_GNU_IFUNC symbols. */
|
|
htab_t loc_hash_table;
|
|
void * loc_hash_memory;
|
|
|
|
/* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt. */
|
|
bfd_vma next_jump_slot_index;
|
|
/* The index of the next R_X86_64_IRELATIVE entry in .rela.plt. */
|
|
bfd_vma next_irelative_index;
|
|
|
|
/* The (unloaded but important) .rel.plt.unloaded section on VxWorks.
|
|
This is used for i386 only. */
|
|
asection *srelplt2;
|
|
|
|
/* The index of the next unused R_386_TLS_DESC slot in .rel.plt. This
|
|
is only used for i386. */
|
|
bfd_vma next_tls_desc_index;
|
|
|
|
/* DT_RELR bitmap. */
|
|
struct elf_dt_relr_bitmap dt_relr_bitmap;
|
|
|
|
/* Relative relocation data. */
|
|
struct elf_x86_relative_reloc_data relative_reloc;
|
|
|
|
/* Unaligned relative relocation data. */
|
|
struct elf_x86_relative_reloc_data unaligned_relative_reloc;
|
|
|
|
/* Number of relative reloc generation pass. */
|
|
unsigned int generate_relative_reloc_pass;
|
|
|
|
/* Value used to fill the unused bytes of the first PLT entry. This
|
|
is only used for i386. */
|
|
bfd_byte plt0_pad_byte;
|
|
|
|
/* TRUE if GOT is referenced. */
|
|
unsigned int got_referenced : 1;
|
|
|
|
/* TRUE if PLT is PC-relative. PLT in PDE and PC-relative PLT in PIE
|
|
can be used as function address.
|
|
|
|
NB: i386 has non-PIC PLT and PIC PLT. Only non-PIC PLT in PDE can
|
|
be used as function address. PIC PLT in PIE can't be used as
|
|
function address. */
|
|
unsigned int pcrel_plt : 1;
|
|
|
|
bfd_vma (*r_info) (bfd_vma, bfd_vma);
|
|
bfd_vma (*r_sym) (bfd_vma);
|
|
bool (*is_reloc_section) (const char *);
|
|
unsigned int sizeof_reloc;
|
|
unsigned int got_entry_size;
|
|
unsigned int pointer_r_type;
|
|
unsigned int relative_r_type;
|
|
int dynamic_interpreter_size;
|
|
const char *dynamic_interpreter;
|
|
const char *tls_get_addr;
|
|
const char *relative_r_name;
|
|
void (*elf_append_reloc) (bfd *, asection *, Elf_Internal_Rela *);
|
|
void (*elf_write_addend) (bfd *, uint64_t, void *);
|
|
void (*elf_write_addend_in_got) (bfd *, uint64_t, void *);
|
|
|
|
/* Options passed from the linker. */
|
|
struct elf_linker_x86_params *params;
|
|
};
|
|
|
|
struct elf_x86_init_table
|
|
{
|
|
/* The lazy PLT layout. */
|
|
const struct elf_x86_lazy_plt_layout *lazy_plt;
|
|
|
|
/* The non-lazy PLT layout. */
|
|
const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
|
|
|
|
/* The lazy PLT layout for IBT. */
|
|
const struct elf_x86_lazy_plt_layout *lazy_ibt_plt;
|
|
|
|
/* The non-lazy PLT layout for IBT. */
|
|
const struct elf_x86_non_lazy_plt_layout *non_lazy_ibt_plt;
|
|
|
|
bfd_byte plt0_pad_byte;
|
|
|
|
bfd_vma (*r_info) (bfd_vma, bfd_vma);
|
|
bfd_vma (*r_sym) (bfd_vma);
|
|
};
|
|
|
|
struct elf_x86_obj_tdata
|
|
{
|
|
struct elf_obj_tdata root;
|
|
|
|
/* tls_type for each local got entry. */
|
|
char *local_got_tls_type;
|
|
|
|
/* GOTPLT entries for TLS descriptors. */
|
|
bfd_vma *local_tlsdesc_gotent;
|
|
|
|
/* R_*_RELATIVE relocation in GOT for this local symbol has been
|
|
processed. */
|
|
char *relative_reloc_done;
|
|
};
|
|
|
|
enum elf_x86_plt_type
|
|
{
|
|
plt_non_lazy = 0,
|
|
plt_lazy = 1 << 0,
|
|
plt_pic = 1 << 1,
|
|
plt_second = 1 << 2,
|
|
plt_unknown = -1
|
|
};
|
|
|
|
struct elf_x86_plt
|
|
{
|
|
const char *name;
|
|
asection *sec;
|
|
bfd_byte *contents;
|
|
enum elf_x86_plt_type type;
|
|
unsigned int plt_got_offset;
|
|
unsigned int plt_entry_size;
|
|
unsigned int plt_got_insn_size; /* Only used for x86-64. */
|
|
long count;
|
|
};
|
|
|
|
/* Set if a relocation is converted from a GOTPCREL relocation. */
|
|
#define R_X86_64_converted_reloc_bit (1 << 7)
|
|
|
|
#define elf_x86_tdata(abfd) \
|
|
((struct elf_x86_obj_tdata *) (abfd)->tdata.any)
|
|
|
|
#define elf_x86_local_got_tls_type(abfd) \
|
|
(elf_x86_tdata (abfd)->local_got_tls_type)
|
|
|
|
#define elf_x86_local_tlsdesc_gotent(abfd) \
|
|
(elf_x86_tdata (abfd)->local_tlsdesc_gotent)
|
|
|
|
#define elf_x86_relative_reloc_done(abfd) \
|
|
(elf_x86_tdata (abfd)->relative_reloc_done)
|
|
|
|
#define elf_x86_compute_jump_table_size(htab) \
|
|
((htab)->elf.srelplt->reloc_count * (htab)->got_entry_size)
|
|
|
|
#define is_x86_elf(bfd, htab) \
|
|
(bfd_get_flavour (bfd) == bfd_target_elf_flavour \
|
|
&& elf_tdata (bfd) != NULL \
|
|
&& elf_object_id (bfd) == (htab)->elf.hash_table_id)
|
|
|
|
/* Rename some of the generic section flags to better document how they
|
|
are used here. */
|
|
#define check_relocs_failed sec_flg0
|
|
#define relative_reloc_packed sec_flg1
|
|
|
|
extern bool _bfd_x86_elf_mkobject
|
|
(bfd *);
|
|
|
|
extern void _bfd_x86_elf_set_tls_module_base
|
|
(struct bfd_link_info *);
|
|
|
|
extern bfd_vma _bfd_x86_elf_dtpoff_base
|
|
(struct bfd_link_info *);
|
|
|
|
extern bool _bfd_x86_elf_readonly_dynrelocs
|
|
(struct elf_link_hash_entry *, void *);
|
|
|
|
extern struct elf_link_hash_entry * _bfd_elf_x86_get_local_sym_hash
|
|
(struct elf_x86_link_hash_table *, bfd *, const Elf_Internal_Rela *,
|
|
bool);
|
|
|
|
extern hashval_t _bfd_x86_elf_local_htab_hash
|
|
(const void *);
|
|
|
|
extern int _bfd_x86_elf_local_htab_eq
|
|
(const void *, const void *);
|
|
|
|
extern struct bfd_hash_entry * _bfd_x86_elf_link_hash_newfunc
|
|
(struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
|
|
|
|
extern struct bfd_link_hash_table * _bfd_x86_elf_link_hash_table_create
|
|
(bfd *);
|
|
|
|
extern int _bfd_x86_elf_compare_relocs
|
|
(const void *, const void *);
|
|
|
|
extern bool _bfd_x86_elf_link_check_relocs
|
|
(bfd *, struct bfd_link_info *);
|
|
|
|
extern bool _bfd_x86_elf_check_relocs
|
|
(bfd *, struct bfd_link_info *, asection *,
|
|
const Elf_Internal_Rela *);
|
|
|
|
extern bool _bfd_x86_elf_link_relax_section
|
|
(bfd *, asection *, struct bfd_link_info *, bool *);
|
|
|
|
extern bool _bfd_elf_x86_size_relative_relocs
|
|
(struct bfd_link_info *, bool *);
|
|
|
|
extern bool _bfd_elf_x86_finish_relative_relocs
|
|
(struct bfd_link_info *);
|
|
|
|
extern void _bfd_elf32_write_addend (bfd *, uint64_t, void *);
|
|
extern void _bfd_elf64_write_addend (bfd *, uint64_t, void *);
|
|
|
|
extern bool _bfd_elf_x86_valid_reloc_p
|
|
(asection *, struct bfd_link_info *, struct elf_x86_link_hash_table *,
|
|
const Elf_Internal_Rela *, struct elf_link_hash_entry *,
|
|
Elf_Internal_Sym *, Elf_Internal_Shdr *, bool *);
|
|
|
|
extern bool _bfd_x86_elf_size_dynamic_sections
|
|
(bfd *, struct bfd_link_info *);
|
|
|
|
extern struct elf_x86_link_hash_table *_bfd_x86_elf_finish_dynamic_sections
|
|
(bfd *, struct bfd_link_info *);
|
|
|
|
extern bool _bfd_x86_elf_always_size_sections
|
|
(bfd *, struct bfd_link_info *);
|
|
|
|
extern void _bfd_x86_elf_merge_symbol_attribute
|
|
(struct elf_link_hash_entry *, unsigned int, bool, bool);
|
|
|
|
extern void _bfd_x86_elf_copy_indirect_symbol
|
|
(struct bfd_link_info *, struct elf_link_hash_entry *,
|
|
struct elf_link_hash_entry *);
|
|
|
|
extern bool _bfd_x86_elf_fixup_symbol
|
|
(struct bfd_link_info *, struct elf_link_hash_entry *);
|
|
|
|
extern bool _bfd_x86_elf_hash_symbol
|
|
(struct elf_link_hash_entry *);
|
|
|
|
extern bool _bfd_x86_elf_adjust_dynamic_symbol
|
|
(struct bfd_link_info *, struct elf_link_hash_entry *);
|
|
|
|
extern void _bfd_x86_elf_hide_symbol
|
|
(struct bfd_link_info *, struct elf_link_hash_entry *, bool);
|
|
|
|
extern bool _bfd_x86_elf_link_symbol_references_local
|
|
(struct bfd_link_info *, struct elf_link_hash_entry *);
|
|
|
|
extern asection * _bfd_x86_elf_gc_mark_hook
|
|
(asection *, struct bfd_link_info *, Elf_Internal_Rela *,
|
|
struct elf_link_hash_entry *, Elf_Internal_Sym *);
|
|
|
|
extern long _bfd_x86_elf_get_synthetic_symtab
|
|
(bfd *, long, long, bfd_vma, struct elf_x86_plt [], asymbol **,
|
|
asymbol **);
|
|
|
|
extern enum elf_property_kind _bfd_x86_elf_parse_gnu_properties
|
|
(bfd *, unsigned int, bfd_byte *, unsigned int);
|
|
|
|
extern bool _bfd_x86_elf_merge_gnu_properties
|
|
(struct bfd_link_info *, bfd *, bfd *, elf_property *, elf_property *);
|
|
|
|
extern void _bfd_x86_elf_link_fixup_gnu_properties
|
|
(struct bfd_link_info *, elf_property_list **);
|
|
|
|
extern bfd * _bfd_x86_elf_link_setup_gnu_properties
|
|
(struct bfd_link_info *, struct elf_x86_init_table *);
|
|
|
|
extern void _bfd_x86_elf_link_fixup_ifunc_symbol
|
|
(struct bfd_link_info *, struct elf_x86_link_hash_table *,
|
|
struct elf_link_hash_entry *, Elf_Internal_Sym *sym);
|
|
|
|
extern void _bfd_x86_elf_link_report_relative_reloc
|
|
(struct bfd_link_info *, asection *, struct elf_link_hash_entry *,
|
|
Elf_Internal_Sym *, const char *, const void *);
|
|
|
|
#define bfd_elf64_mkobject \
|
|
_bfd_x86_elf_mkobject
|
|
#define bfd_elf32_mkobject \
|
|
_bfd_x86_elf_mkobject
|
|
#define bfd_elf64_bfd_link_hash_table_create \
|
|
_bfd_x86_elf_link_hash_table_create
|
|
#define bfd_elf32_bfd_link_hash_table_create \
|
|
_bfd_x86_elf_link_hash_table_create
|
|
#define bfd_elf64_bfd_link_check_relocs \
|
|
_bfd_x86_elf_link_check_relocs
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#define bfd_elf32_bfd_link_check_relocs \
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_bfd_x86_elf_link_check_relocs
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#define bfd_elf32_bfd_relax_section \
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_bfd_x86_elf_link_relax_section
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#define bfd_elf64_bfd_relax_section \
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_bfd_x86_elf_link_relax_section
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#define elf_backend_check_relocs \
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_bfd_x86_elf_check_relocs
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#define elf_backend_size_dynamic_sections \
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_bfd_x86_elf_size_dynamic_sections
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#define elf_backend_merge_symbol_attribute \
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_bfd_x86_elf_merge_symbol_attribute
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#define elf_backend_copy_indirect_symbol \
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_bfd_x86_elf_copy_indirect_symbol
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#define elf_backend_fixup_symbol \
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_bfd_x86_elf_fixup_symbol
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#define elf_backend_hash_symbol \
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_bfd_x86_elf_hash_symbol
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#define elf_backend_adjust_dynamic_symbol \
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_bfd_x86_elf_adjust_dynamic_symbol
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#define elf_backend_gc_mark_hook \
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_bfd_x86_elf_gc_mark_hook
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#define elf_backend_omit_section_dynsym \
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_bfd_elf_omit_section_dynsym_all
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#define elf_backend_parse_gnu_properties \
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_bfd_x86_elf_parse_gnu_properties
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#define elf_backend_merge_gnu_properties \
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_bfd_x86_elf_merge_gnu_properties
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#define elf_backend_fixup_gnu_properties \
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_bfd_x86_elf_link_fixup_gnu_properties
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#define elf_backend_size_relative_relocs \
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_bfd_elf_x86_size_relative_relocs
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#define elf_backend_finish_relative_relocs \
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_bfd_elf_x86_finish_relative_relocs
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#define ELF_P_ALIGN ELF_MINPAGESIZE
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/* Allocate x86 GOT info for local symbols. */
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static inline bool
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elf_x86_allocate_local_got_info (bfd *abfd, bfd_size_type count)
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{
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bfd_signed_vma *local_got_refcounts = elf_local_got_refcounts (abfd);
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if (local_got_refcounts == NULL)
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{
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bfd_size_type size = count * (sizeof (bfd_signed_vma)
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+ sizeof (bfd_vma)
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+ 2 * sizeof(char));
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local_got_refcounts = (bfd_signed_vma *) bfd_zalloc (abfd, size);
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if (local_got_refcounts == NULL)
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return false;
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elf_local_got_refcounts (abfd) = local_got_refcounts;
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elf_x86_local_tlsdesc_gotent (abfd) =
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(bfd_vma *) (local_got_refcounts + count);
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elf_x86_local_got_tls_type (abfd) =
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(char *) (local_got_refcounts + 2 * count);
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elf_x86_relative_reloc_done (abfd) =
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((char *) (local_got_refcounts + 2 * count)) + count;
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}
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return true;
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}
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