[thirdparty/binutils-gdb.git] / bfd / elfxx-x86.h

/* x86 specific support for ELF
   Copyright (C) 2017 Free Software Foundation, Inc.

   This file is part of BFD, the Binary File Descriptor library.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#include "sysdep.h"
#include "bfd.h"
#include "bfdlink.h"
#include "libbfd.h"
#include "elf-bfd.h"
#include "bfd_stdint.h"
#include "hashtab.h"

#define PLT_CIE_LENGTH		20
#define PLT_FDE_LENGTH		36
#define PLT_FDE_START_OFFSET	4 + PLT_CIE_LENGTH + 8
#define PLT_FDE_LEN_OFFSET	4 + PLT_CIE_LENGTH + 12

#define ABI_64_P(abfd) \
  (get_elf_backend_data (abfd)->s->elfclass == ELFCLASS64)

/* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
   copying dynamic variables from a shared lib into an app's dynbss
   section, and instead use a dynamic relocation to point into the
   shared lib.  */
#define ELIMINATE_COPY_RELOCS 1

#define elf_x86_hash_table(p, id) \
  (elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) == (id) \
    ? ((struct elf_x86_link_hash_table *) ((p)->hash)) : NULL)

/* Is a undefined weak symbol which is resolved to 0.  Reference to an
   undefined weak symbol is resolved to 0 when building executable if
   it isn't dynamic and
   1. Has non-GOT/non-PLT relocations in text section.  Or
   2. Has no GOT/PLT relocation.
   Local undefined weak symbol is always resolved to 0.
 */
#define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, ID, GOT_RELOC, EH) \
  ((EH)->elf.root.type == bfd_link_hash_undefweak		 \
   && ((EH)->elf.forced_local					 \
       || (bfd_link_executable (INFO)				 \
	   && (elf_x86_hash_table ((INFO), (ID))->interp == NULL \
	       || !(GOT_RELOC)					 \
	       || (EH)->has_non_got_reloc			 \
	       || !(INFO)->dynamic_undefined_weak))))

/* Should copy relocation be generated for a symbol.  Don't generate
   copy relocation against a protected symbol defined in a shared
   object with GNU_PROPERTY_NO_COPY_ON_PROTECTED.  */
#define SYMBOL_NO_COPYRELOC(INFO, EH) \
  ((EH)->def_protected \
   && ((EH)->elf.root.type == bfd_link_hash_defined \
       || (EH)->elf.root.type == bfd_link_hash_defweak) \
   && elf_has_no_copy_on_protected ((EH)->elf.root.u.def.section->owner) \
   && ((EH)->elf.root.u.def.section->owner->flags & DYNAMIC) != 0 \
   && ((EH)->elf.root.u.def.section->flags & SEC_CODE) == 0)

/* x86 ELF linker hash entry.  */

struct elf_x86_link_hash_entry
{
  struct elf_link_hash_entry elf;

  /* Track dynamic relocs copied for this symbol.  */
  struct elf_dyn_relocs *dyn_relocs;

  unsigned char tls_type;

  /* TRUE if symbol has GOT or PLT relocations.  */
  unsigned int has_got_reloc : 1;

  /* TRUE if symbol has non-GOT/non-PLT relocations in text sections.  */
  unsigned int has_non_got_reloc : 1;

  /* Don't call finish_dynamic_symbol on this symbol.  */
  unsigned int no_finish_dynamic_symbol : 1;

  /* TRUE if symbol is __tls_get_addr.  */
  unsigned int tls_get_addr : 1;

  /* TRUE if symbol is defined as a protected symbol.  */
  unsigned int def_protected : 1;

  /* Symbol is referenced by R_386_GOTOFF relocation.  This is only used
     by i386.  */
  unsigned int gotoff_ref : 1;

  /* TRUE if a weak symbol with a real definition needs a copy reloc.
     When there is a weak symbol with a real definition, the processor
     independent code will have arranged for us to see the real
     definition first.  We need to copy the needs_copy bit from the
     real definition and check it when allowing copy reloc in PIE.  This
     is only used by x86-64.  */
  unsigned int needs_copy : 1;

  /* Reference count of C/C++ function pointer relocations in read-write
     section which can be resolved at run-time.  */
  bfd_signed_vma func_pointer_refcount;

  /* Information about the GOT PLT entry. Filled when there are both
     GOT and PLT relocations against the same function.  */
  union gotplt_union plt_got;

  /* Information about the second PLT entry.   */
  union gotplt_union plt_second;

  /* Offset of the GOTPLT entry reserved for the TLS descriptor,
     starting at the end of the jump table.  */
  bfd_vma tlsdesc_got;
};

struct elf_x86_lazy_plt_layout
{
  /* The first entry in an absolute lazy procedure linkage table looks
     like this.  */
  const bfd_byte *plt0_entry;
  unsigned int plt0_entry_size;          /* Size of PLT0 entry.  */

  /* Later entries in an absolute lazy procedure linkage table look
     like this.  */
  const bfd_byte *plt_entry;
  unsigned int plt_entry_size;          /* Size of each PLT entry.  */

  /* 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 an absolute 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.  */
  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.
     This is only used for i386 where absolute PLT0 and PIC PLT0 are
     different.  */
  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;

  /* .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_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))

/* 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;

  /* Small local sym cache.  */
  struct sym_cache sym_cache;

  /* _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 offset into splt of the PLT entry for the TLS descriptor
     resolver.  Special values are 0, if not necessary (or not found
     to be necessary yet), and -1 if needed but not determined
     yet.  */
  bfd_vma tlsdesc_plt;

  /* The offset into sgot of the GOT entry used by the PLT entry
     above.  */
  bfd_vma tlsdesc_got;

  /* 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;

  /* TRUE if there are dynamic relocs against IFUNC symbols that apply
     to read-only sections.  */
  bfd_boolean readonly_dynrelocs_against_ifunc;

  /* TRUE if this is a VxWorks x86 target.  */
  bfd_boolean is_vxworks;

  /* 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 used for i386 only.  */
  bfd_vma next_tls_desc_index;

  bfd_vma (*r_info) (bfd_vma, bfd_vma);
  bfd_vma (*r_sym) (bfd_vma);
  enum elf_target_id target_id;
  unsigned int sizeof_reloc;
  unsigned int got_entry_size;
  unsigned int pointer_r_type;
  int dynamic_interpreter_size;
  const char *dynamic_interpreter;
  const char *tls_get_addr;
};

struct elf_x86_plt_layout_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;

  /* TRUE if this is a normal x86 target.  */
  bfd_boolean normal_target;

  /* TRUE if this is a VxWorks x86 target.  */
  bfd_boolean is_vxworks;
};

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;
};

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;
};

#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_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)->target_id)

extern bfd_boolean _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 bfd_boolean _bfd_x86_elf_allocate_dynrelocs
  (struct elf_link_hash_entry *, void *);

extern bfd_boolean _bfd_x86_elf_allocate_local_dynrelocs
  (void **, void *);

extern bfd_boolean _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 *,
   bfd_boolean);

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 bfd_boolean _bfd_x86_elf_link_check_relocs
  (bfd *, struct bfd_link_info *);

extern bfd_boolean _bfd_x86_elf_always_size_sections
  (bfd *, struct bfd_link_info *);

extern void _bfd_x86_elf_merge_symbol_attribute
  (struct elf_link_hash_entry *, const Elf_Internal_Sym *,
   bfd_boolean, bfd_boolean);

extern void _bfd_x86_elf_copy_indirect_symbol
  (struct bfd_link_info *, struct elf_link_hash_entry *,
   struct elf_link_hash_entry *);

extern bfd_boolean _bfd_x86_elf_fixup_symbol
  (struct bfd_link_info *, struct elf_link_hash_entry *);

extern bfd_boolean _bfd_x86_elf_hash_symbol
  (struct elf_link_hash_entry *);

extern bfd_boolean _bfd_x86_elf_adjust_dynamic_symbol
  (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 bfd_boolean _bfd_x86_elf_merge_gnu_properties
  (struct bfd_link_info *, bfd *, elf_property *, elf_property *);

extern bfd * _bfd_x86_elf_link_setup_gnu_properties
  (struct bfd_link_info *, struct elf_x86_plt_layout_table *);

#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
#define bfd_elf32_bfd_link_check_relocs \
  _bfd_x86_elf_link_check_relocs

#define elf_backend_always_size_sections \
  _bfd_x86_elf_always_size_sections
#define elf_backend_merge_symbol_attribute \
  _bfd_x86_elf_merge_symbol_attribute
#define elf_backend_copy_indirect_symbol \
  _bfd_x86_elf_copy_indirect_symbol
#define elf_backend_fixup_symbol \
  _bfd_x86_elf_fixup_symbol
#define elf_backend_hash_symbol \
  _bfd_x86_elf_hash_symbol
#define elf_backend_adjust_dynamic_symbol \
  _bfd_x86_elf_adjust_dynamic_symbol
#define elf_backend_gc_mark_hook \
  _bfd_x86_elf_gc_mark_hook
#define elf_backend_omit_section_dynsym \
  ((bfd_boolean (*) (bfd *, struct bfd_link_info *, asection *)) bfd_true)
#define elf_backend_parse_gnu_properties \
  _bfd_x86_elf_parse_gnu_properties
#define elf_backend_merge_gnu_properties \
  _bfd_x86_elf_merge_gnu_properties
Commit	Line	Data
0afcef53 L	1	/* x86 specific support for ELF
	2	Copyright (C) 2017 Free Software Foundation, Inc.
	3
	4	This file is part of BFD, the Binary File Descriptor library.
	5
	6	This program is free software; you can redistribute it and/or modify
	7	it under the terms of the GNU General Public License as published by
	8	the Free Software Foundation; either version 3 of the License, or
	9	(at your option) any later version.
	10
	11	This program is distributed in the hope that it will be useful,
	12	but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	GNU General Public License for more details.
	15
	16	You should have received a copy of the GNU General Public License
	17	along with this program; if not, write to the Free Software
	18	Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
	19	MA 02110-1301, USA. */
	20
	21	#include "sysdep.h"
	22	#include "bfd.h"
	23	#include "bfdlink.h"
	24	#include "libbfd.h"
	25	#include "elf-bfd.h"
	26	#include "bfd_stdint.h"
0afcef53 L	27	#include "hashtab.h"
0afcef53 L	28
aa595247 L	29	#define PLT_CIE_LENGTH 20
	30	#define PLT_FDE_LENGTH 36
	31	#define PLT_FDE_START_OFFSET 4 + PLT_CIE_LENGTH + 8
	32	#define PLT_FDE_LEN_OFFSET 4 + PLT_CIE_LENGTH + 12
	33
765e526c L	34	#define ABI_64_P(abfd) \
	35	(get_elf_backend_data (abfd)->s->elfclass == ELFCLASS64)
	36
0afcef53 L	37	/* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
	38	copying dynamic variables from a shared lib into an app's dynbss
	39	section, and instead use a dynamic relocation to point into the
	40	shared lib. */
	41	#define ELIMINATE_COPY_RELOCS 1
	42
	43	#define elf_x86_hash_table(p, id) \
	44	(elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) == (id) \
	45	? ((struct elf_x86_link_hash_table *) ((p)->hash)) : NULL)
	46
	47	/* Is a undefined weak symbol which is resolved to 0. Reference to an
	48	undefined weak symbol is resolved to 0 when building executable if
	49	it isn't dynamic and
	50	1. Has non-GOT/non-PLT relocations in text section. Or
	51	2. Has no GOT/PLT relocation.
	52	Local undefined weak symbol is always resolved to 0.
	53	*/
	54	#define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, ID, GOT_RELOC, EH) \
	55	((EH)->elf.root.type == bfd_link_hash_undefweak \
	56	&& ((EH)->elf.forced_local \
	57	\|\| (bfd_link_executable (INFO) \
	58	&& (elf_x86_hash_table ((INFO), (ID))->interp == NULL \
	59	\|\| !(GOT_RELOC) \
	60	\|\| (EH)->has_non_got_reloc \
	61	\|\| !(INFO)->dynamic_undefined_weak))))
	62
	63	/* Should copy relocation be generated for a symbol. Don't generate
	64	copy relocation against a protected symbol defined in a shared
	65	object with GNU_PROPERTY_NO_COPY_ON_PROTECTED. */
	66	#define SYMBOL_NO_COPYRELOC(INFO, EH) \
	67	((EH)->def_protected \
	68	&& ((EH)->elf.root.type == bfd_link_hash_defined \
	69	\|\| (EH)->elf.root.type == bfd_link_hash_defweak) \
	70	&& elf_has_no_copy_on_protected ((EH)->elf.root.u.def.section->owner) \
	71	&& ((EH)->elf.root.u.def.section->owner->flags & DYNAMIC) != 0 \
	72	&& ((EH)->elf.root.u.def.section->flags & SEC_CODE) == 0)
	73
	74	/* x86 ELF linker hash entry. */
	75
	76	struct elf_x86_link_hash_entry
	77	{
	78	struct elf_link_hash_entry elf;
	79
	80	/* Track dynamic relocs copied for this symbol. */
	81	struct elf_dyn_relocs *dyn_relocs;
	82
	83	unsigned char tls_type;
	84
	85	/* TRUE if symbol has GOT or PLT relocations. */
	86	unsigned int has_got_reloc : 1;
	87
	88	/* TRUE if symbol has non-GOT/non-PLT relocations in text sections. */
	89	unsigned int has_non_got_reloc : 1;
	90
	91	/* Don't call finish_dynamic_symbol on this symbol. */
	92	unsigned int no_finish_dynamic_symbol : 1;
	93
	94	/* TRUE if symbol is __tls_get_addr. */
	95	unsigned int tls_get_addr : 1;
	96
	97	/* TRUE if symbol is defined as a protected symbol. */
	98	unsigned int def_protected : 1;
	99
	100	/* Symbol is referenced by R_386_GOTOFF relocation. This is only used
101	by i386. */
102	unsigned int gotoff_ref : 1;
103
104	/* TRUE if a weak symbol with a real definition needs a copy reloc.
105	When there is a weak symbol with a real definition, the processor
106	independent code will have arranged for us to see the real
107	definition first. We need to copy the needs_copy bit from the
108	real definition and check it when allowing copy reloc in PIE. This
109	is only used by x86-64. */
110	unsigned int needs_copy : 1;
111
112	/* Reference count of C/C++ function pointer relocations in read-write
113	section which can be resolved at run-time. */
114	bfd_signed_vma func_pointer_refcount;
115
116	/* Information about the GOT PLT entry. Filled when there are both
117	GOT and PLT relocations against the same function. */
118	union gotplt_union plt_got;
119
120	/* Information about the second PLT entry. */
121	union gotplt_union plt_second;
122
123	/* Offset of the GOTPLT entry reserved for the TLS descriptor,
124	starting at the end of the jump table. */
125	bfd_vma tlsdesc_got;
126	};
127
765e526c L	128	struct elf_x86_lazy_plt_layout
	129	{
	130	/* The first entry in an absolute lazy procedure linkage table looks
	131	like this. */
	132	const bfd_byte *plt0_entry;
	133	unsigned int plt0_entry_size; /* Size of PLT0 entry. */
	134
	135	/* Later entries in an absolute lazy procedure linkage table look
	136	like this. */
	137	const bfd_byte *plt_entry;
	138	unsigned int plt_entry_size; /* Size of each PLT entry. */
	139
	140	/* Offsets into plt0_entry that are to be replaced with GOT[1] and
	141	GOT[2]. */
	142	unsigned int plt0_got1_offset;
	143	unsigned int plt0_got2_offset;
	144
	145	/* Offset of the end of the PC-relative instruction containing
	146	plt0_got2_offset. This is for x86-64 only. */
	147	unsigned int plt0_got2_insn_end;
	148
	149	/* Offsets into plt_entry that are to be replaced with... */
	150	unsigned int plt_got_offset; /* ... address of this symbol in .got. */
	151	unsigned int plt_reloc_offset; /* ... offset into relocation table. */
	152	unsigned int plt_plt_offset; /* ... offset to start of .plt. */
	153
	154	/* Length of the PC-relative instruction containing plt_got_offset.
	155	This is used for x86-64 only. */
	156	unsigned int plt_got_insn_size;
	157
	158	/* Offset of the end of the PC-relative jump to plt0_entry. This is
	159	used for x86-64 only. */
	160	unsigned int plt_plt_insn_end;
	161
	162	/* Offset into plt_entry where the initial value of the GOT entry
	163	points. */
	164	unsigned int plt_lazy_offset;
	165
	166	/* The first entry in a PIC lazy procedure linkage table looks like
a6798bab	167	this. */
765e526c L	168	const bfd_byte *pic_plt0_entry;
	169
	170	/* Subsequent entries in a PIC lazy procedure linkage table look
a6798bab	171	like this. */
765e526c L	172	const bfd_byte *pic_plt_entry;
	173
	174	/* .eh_frame covering the lazy .plt section. */
	175	const bfd_byte *eh_frame_plt;
	176	unsigned int eh_frame_plt_size;
	177	};
	178
	179	struct elf_x86_non_lazy_plt_layout
	180	{
	181	/* Entries in an absolute non-lazy procedure linkage table look like
	182	this. */
	183	const bfd_byte *plt_entry;
a6798bab	184	/* Entries in a PIC non-lazy procedure linkage table look like this. */
765e526c L	185	const bfd_byte *pic_plt_entry;
	186
	187	unsigned int plt_entry_size; /* Size of each PLT entry. */
	188
	189	/* Offsets into plt_entry that are to be replaced with... */
	190	unsigned int plt_got_offset; /* ... address of this symbol in .got. */
	191
	192	/* Length of the PC-relative instruction containing plt_got_offset.
	193	This is used for x86-64 only. */
	194	unsigned int plt_got_insn_size;
	195
	196	/* .eh_frame covering the non-lazy .plt section. */
	197	const bfd_byte *eh_frame_plt;
	198	unsigned int eh_frame_plt_size;
	199	};
	200
	201	struct elf_x86_plt_layout
	202	{
	203	/* The first entry in a lazy procedure linkage table looks like this.
	204	This is only used for i386 where absolute PLT0 and PIC PLT0 are
	205	different. */
	206	const bfd_byte *plt0_entry;
	207	/* Entries in a procedure linkage table look like this. */
	208	const bfd_byte *plt_entry;
	209	unsigned int plt_entry_size; /* Size of each PLT entry. */
	210
	211	/* 1 has PLT0. */
	212	unsigned int has_plt0;
	213
	214	/* Offsets into plt_entry that are to be replaced with... */
	215	unsigned int plt_got_offset; /* ... address of this symbol in .got. */
	216
	217	/* Length of the PC-relative instruction containing plt_got_offset.
	218	This is only used for x86-64. */
	219	unsigned int plt_got_insn_size;
	220
	221	/* .eh_frame covering the .plt section. */
	222	const bfd_byte *eh_frame_plt;
	223	unsigned int eh_frame_plt_size;
	224	};
	225
6b9553e2	226	/* Values in tls_type of x86 ELF linker hash entry. */
0afcef53 L	227	#define GOT_UNKNOWN 0
	228	#define GOT_NORMAL 1
	229	#define GOT_TLS_GD 2
6b9553e2 L	230	#define GOT_TLS_IE 4
	231	#define GOT_TLS_IE_POS 5
	232	#define GOT_TLS_IE_NEG 6
	233	#define GOT_TLS_IE_BOTH 7
	234	#define GOT_TLS_GDESC 8
	235	#define GOT_TLS_GD_BOTH_P(type) \
	236	((type) == (GOT_TLS_GD \| GOT_TLS_GDESC))
	237	#define GOT_TLS_GD_P(type) \
	238	((type) == GOT_TLS_GD \|\| GOT_TLS_GD_BOTH_P (type))
	239	#define GOT_TLS_GDESC_P(type) \
	240	((type) == GOT_TLS_GDESC \|\| GOT_TLS_GD_BOTH_P (type))
	241	#define GOT_TLS_GD_ANY_P(type) \
	242	(GOT_TLS_GD_P (type) \|\| GOT_TLS_GDESC_P (type))
0afcef53 L	243
	244	#define elf_x86_hash_entry(ent) \
	245	((struct elf_x86_link_hash_entry *)(ent))
	246
	247	/* x86 ELF linker hash table. */
	248
	249	struct elf_x86_link_hash_table
	250	{
	251	struct elf_link_hash_table elf;
	252
	253	/* Short-cuts to get to dynamic linker sections. */
	254	asection *interp;
	255	asection *plt_eh_frame;
	256	asection *plt_second;
	257	asection *plt_second_eh_frame;
	258	asection *plt_got;
	259	asection *plt_got_eh_frame;
	260
765e526c L	261	/* Parameters describing PLT generation, lazy or non-lazy. */
	262	struct elf_x86_plt_layout plt;
	263
	264	/* Parameters describing lazy PLT generation. */
	265	const struct elf_x86_lazy_plt_layout *lazy_plt;
	266
	267	/* Parameters describing non-lazy PLT generation. */
	268	const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
	269
0afcef53 L	270	union
	271	{
	272	bfd_signed_vma refcount;
	273	bfd_vma offset;
	274	} tls_ld_or_ldm_got;
	275
	276	/* The amount of space used by the jump slots in the GOT. */
	277	bfd_vma sgotplt_jump_table_size;
	278
	279	/* Small local sym cache. */
	280	struct sym_cache sym_cache;
	281
	282	/* _TLS_MODULE_BASE_ symbol. */
	283	struct bfd_link_hash_entry *tls_module_base;
	284
	285	/* Used by local STT_GNU_IFUNC symbols. */
	286	htab_t loc_hash_table;
	287	void * loc_hash_memory;
	288
	289	/* The offset into splt of the PLT entry for the TLS descriptor
	290	resolver. Special values are 0, if not necessary (or not found
	291	to be necessary yet), and -1 if needed but not determined
	292	yet. */
	293	bfd_vma tlsdesc_plt;
	294
	295	/* The offset into sgot of the GOT entry used by the PLT entry
	296	above. */
	297	bfd_vma tlsdesc_got;
	298
	299	/* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt. */
	300	bfd_vma next_jump_slot_index;
	301	/* The index of the next R_X86_64_IRELATIVE entry in .rela.plt. */
	302	bfd_vma next_irelative_index;
	303
	304	/* TRUE if there are dynamic relocs against IFUNC symbols that apply
	305	to read-only sections. */
	306	bfd_boolean readonly_dynrelocs_against_ifunc;
	307
eeb2f20a L	308	/* TRUE if this is a VxWorks x86 target. */
	309	bfd_boolean is_vxworks;
	310
765e526c L	311	/* The (unloaded but important) .rel.plt.unloaded section on VxWorks.
	312	This is used for i386 only. */
	313	asection *srelplt2;
	314
	315	/* The index of the next unused R_386_TLS_DESC slot in .rel.plt. This
	316	is used for i386 only. */
	317	bfd_vma next_tls_desc_index;
	318
0afcef53 L	319	bfd_vma (*r_info) (bfd_vma, bfd_vma);
0afcef53 L	320	bfd_vma (*r_sym) (bfd_vma);
fe53b4a4	321	enum elf_target_id target_id;
503294e7	322	unsigned int sizeof_reloc;
9ff114ca	323	unsigned int got_entry_size;
0afcef53 L	324	unsigned int pointer_r_type;
	325	int dynamic_interpreter_size;
	326	const char *dynamic_interpreter;
	327	const char *tls_get_addr;
	328	};
	329
a6798bab L	330	struct elf_x86_plt_layout_table
	331	{
	332	/* The lazy PLT layout. */
	333	const struct elf_x86_lazy_plt_layout *lazy_plt;
	334
	335	/* The non-lazy PLT layout. */
	336	const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
	337
	338	/* The lazy PLT layout for IBT. */
	339	const struct elf_x86_lazy_plt_layout *lazy_ibt_plt;
	340
	341	/* The non-lazy PLT layout for IBT. */
	342	const struct elf_x86_non_lazy_plt_layout *non_lazy_ibt_plt;
	343
c6295c22	344	/* TRUE if this is a normal x86 target. */
a6798bab L	345	bfd_boolean normal_target;
	346
	347	/* TRUE if this is a VxWorks x86 target. */
	348	bfd_boolean is_vxworks;
	349	};
	350
0afcef53 L	351	struct elf_x86_obj_tdata
	352	{
	353	struct elf_obj_tdata root;
	354
	355	/* tls_type for each local got entry. */
	356	char *local_got_tls_type;
	357
	358	/* GOTPLT entries for TLS descriptors. */
	359	bfd_vma *local_tlsdesc_gotent;
	360	};
	361
f493882d L	362	enum elf_x86_plt_type
	363	{
	364	plt_non_lazy = 0,
	365	plt_lazy = 1 << 0,
	366	plt_pic = 1 << 1,
	367	plt_second = 1 << 2,
	368	plt_unknown = -1
	369	};
	370
	371	struct elf_x86_plt
	372	{
	373	const char *name;
	374	asection *sec;
	375	bfd_byte *contents;
	376	enum elf_x86_plt_type type;
	377	unsigned int plt_got_offset;
	378	unsigned int plt_entry_size;
	379	unsigned int plt_got_insn_size; /* Only used for x86-64. */
	380	long count;
	381	};
	382
0afcef53 L	383	#define elf_x86_tdata(abfd) \
	384	((struct elf_x86_obj_tdata *) (abfd)->tdata.any)
	385
	386	#define elf_x86_local_got_tls_type(abfd) \
	387	(elf_x86_tdata (abfd)->local_got_tls_type)
	388
	389	#define elf_x86_local_tlsdesc_gotent(abfd) \
	390	(elf_x86_tdata (abfd)->local_tlsdesc_gotent)
	391
9ff114ca L	392	#define elf_x86_compute_jump_table_size(htab) \
	393	((htab)->elf.srelplt->reloc_count * (htab)->got_entry_size)
	394
fe53b4a4 L	395	#define is_x86_elf(bfd, htab) \
	396	(bfd_get_flavour (bfd) == bfd_target_elf_flavour \
	397	&& elf_tdata (bfd) != NULL \
	398	&& elf_object_id (bfd) == (htab)->target_id)
	399
39946cc2 L	400	extern bfd_boolean _bfd_x86_elf_mkobject
	401	(bfd *);
	402
0afcef53 L	403	extern void _bfd_x86_elf_set_tls_module_base
	404	(struct bfd_link_info *);
	405
	406	extern bfd_vma _bfd_x86_elf_dtpoff_base
	407	(struct bfd_link_info *);
	408
b9ce864c L	409	extern bfd_boolean _bfd_x86_elf_allocate_dynrelocs
	410	(struct elf_link_hash_entry , void );
	411
	412	extern bfd_boolean _bfd_x86_elf_allocate_local_dynrelocs
	413	(void *, void );
	414
0afcef53 L	415	extern bfd_boolean _bfd_x86_elf_readonly_dynrelocs
	416	(struct elf_link_hash_entry , void );
	417
	418	extern struct elf_link_hash_entry * _bfd_elf_x86_get_local_sym_hash
	419	(struct elf_x86_link_hash_table , bfd , const Elf_Internal_Rela *,
	420	bfd_boolean);
	421
	422	extern hashval_t _bfd_x86_elf_local_htab_hash
	423	(const void *);
	424
	425	extern int _bfd_x86_elf_local_htab_eq
	426	(const void , const void );
	427
	428	extern struct bfd_hash_entry * _bfd_x86_elf_link_hash_newfunc
	429	(struct bfd_hash_entry , struct bfd_hash_table , const char *);
	430
765e526c	431	extern struct bfd_link_hash_table * _bfd_x86_elf_link_hash_table_create
0afcef53 L	432	(bfd *);
	433
	434	extern int _bfd_x86_elf_compare_relocs
	435	(const void , const void );
	436
	437	extern bfd_boolean _bfd_x86_elf_link_check_relocs
	438	(bfd , struct bfd_link_info );
	439
	440	extern bfd_boolean _bfd_x86_elf_always_size_sections
	441	(bfd , struct bfd_link_info );
	442
	443	extern void _bfd_x86_elf_merge_symbol_attribute
	444	(struct elf_link_hash_entry , const Elf_Internal_Sym ,
	445	bfd_boolean, bfd_boolean);
	446
	447	extern void _bfd_x86_elf_copy_indirect_symbol
	448	(struct bfd_link_info , struct elf_link_hash_entry ,
	449	struct elf_link_hash_entry *);
	450
	451	extern bfd_boolean _bfd_x86_elf_fixup_symbol
	452	(struct bfd_link_info , struct elf_link_hash_entry );
	453
	454	extern bfd_boolean _bfd_x86_elf_hash_symbol
	455	(struct elf_link_hash_entry *);
	456
eeb2f20a L	457	extern bfd_boolean _bfd_x86_elf_adjust_dynamic_symbol
	458	(struct bfd_link_info , struct elf_link_hash_entry );
	459
4f501a24 L	460	extern asection * _bfd_x86_elf_gc_mark_hook
	461	(asection , struct bfd_link_info , Elf_Internal_Rela *,
	462	struct elf_link_hash_entry , Elf_Internal_Sym );
	463
f493882d L	464	extern long _bfd_x86_elf_get_synthetic_symtab
	465	(bfd , long, long, bfd_vma, struct elf_x86_plt [], asymbol *,
	466	asymbol **);
	467
0afcef53 L	468	extern enum elf_property_kind _bfd_x86_elf_parse_gnu_properties
	469	(bfd , unsigned int, bfd_byte , unsigned int);
	470
	471	extern bfd_boolean _bfd_x86_elf_merge_gnu_properties
	472	(struct bfd_link_info , bfd , elf_property , elf_property );
	473
a6798bab L	474	extern bfd * _bfd_x86_elf_link_setup_gnu_properties
	475	(struct bfd_link_info , struct elf_x86_plt_layout_table );
	476
39946cc2 L	477	#define bfd_elf64_mkobject \
	478	_bfd_x86_elf_mkobject
	479	#define bfd_elf32_mkobject \
	480	_bfd_x86_elf_mkobject
765e526c L	481	#define bfd_elf64_bfd_link_hash_table_create \
	482	_bfd_x86_elf_link_hash_table_create
	483	#define bfd_elf32_bfd_link_hash_table_create \
	484	_bfd_x86_elf_link_hash_table_create
0afcef53 L	485	#define bfd_elf64_bfd_link_check_relocs \
	486	_bfd_x86_elf_link_check_relocs
	487	#define bfd_elf32_bfd_link_check_relocs \
	488	_bfd_x86_elf_link_check_relocs
	489
	490	#define elf_backend_always_size_sections \
	491	_bfd_x86_elf_always_size_sections
	492	#define elf_backend_merge_symbol_attribute \
	493	_bfd_x86_elf_merge_symbol_attribute
	494	#define elf_backend_copy_indirect_symbol \
	495	_bfd_x86_elf_copy_indirect_symbol
	496	#define elf_backend_fixup_symbol \
	497	_bfd_x86_elf_fixup_symbol
	498	#define elf_backend_hash_symbol \
	499	_bfd_x86_elf_hash_symbol
eeb2f20a L	500	#define elf_backend_adjust_dynamic_symbol \
eeb2f20a L	501	_bfd_x86_elf_adjust_dynamic_symbol
4f501a24 L	502	#define elf_backend_gc_mark_hook \
4f501a24 L	503	_bfd_x86_elf_gc_mark_hook
0afcef53 L	504	#define elf_backend_omit_section_dynsym \
	505	((bfd_boolean () (bfd , struct bfd_link_info , asection )) bfd_true)
	506	#define elf_backend_parse_gnu_properties \
	507	_bfd_x86_elf_parse_gnu_properties
	508	#define elf_backend_merge_gnu_properties \
	509	_bfd_x86_elf_merge_gnu_properties