bfd/elfxx-x86.h

   1 /* x86 specific support for ELF
   2    Copyright (C) 2017-2021 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 /* Don't generate unused section symbols.  */
  22 #define TARGET_KEEP_UNUSED_SECTION_SYMBOLS false
  23
  24 #include "sysdep.h"
  25 #include "bfd.h"
  26 #include "bfdlink.h"
  27 #include "libbfd.h"
  28 #include "elf-bfd.h"
  29 #include "hashtab.h"
  30 #include "elf-linker-x86.h"
  31
  32 #define PLT_CIE_LENGTH          20
  33 #define PLT_FDE_LENGTH          36
  34 #define PLT_FDE_START_OFFSET    4 + PLT_CIE_LENGTH + 8
  35 #define PLT_FDE_LEN_OFFSET      4 + PLT_CIE_LENGTH + 12
  36
  37 #define ABI_64_P(abfd) \
  38   (get_elf_backend_data (abfd)->s->elfclass == ELFCLASS64)
  39
  40 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
  41    copying dynamic variables from a shared lib into an app's dynbss
  42    section, and instead use a dynamic relocation to point into the
  43    shared lib.  */
  44 #define ELIMINATE_COPY_RELOCS 1
  45
  46 #define elf_x86_hash_table(p, id) \
  47   (is_elf_hash_table ((p)->hash) \
  48    && elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) == (id) \
  49     ? ((struct elf_x86_link_hash_table *) ((p)->hash)) : NULL)
  50
  51 /* Will references to this symbol always be local in this object?  */
  52 #define SYMBOL_REFERENCES_LOCAL_P(INFO, H) \
  53   _bfd_x86_elf_link_symbol_references_local ((INFO), (H))
  54
  55 /* TRUE if an undefined weak symbol should be resolved to 0.  Local
  56    undefined weak symbol is always resolved to 0.  Reference to an
  57    undefined weak symbol is resolved to 0 in executable if undefined
  58    weak symbol should be resolved to 0 (zero_undefweak > 0).  */
  59 #define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, EH) \
  60   ((EH)->elf.root.type == bfd_link_hash_undefweak                \
  61    && (SYMBOL_REFERENCES_LOCAL_P ((INFO), &(EH)->elf)            \
  62        || (bfd_link_executable (INFO)                            \
  63            && (EH)->zero_undefweak > 0)))
  64
  65 /* Should copy relocation be generated for a symbol.  Don't generate
  66    copy relocation against a protected symbol defined in a shared
  67    object with GNU_PROPERTY_NO_COPY_ON_PROTECTED.  */
  68 #define SYMBOL_NO_COPYRELOC(INFO, EH) \
  69   ((EH)->def_protected \
  70    && ((EH)->elf.root.type == bfd_link_hash_defined \
  71        || (EH)->elf.root.type == bfd_link_hash_defweak) \
  72    && elf_has_no_copy_on_protected ((EH)->elf.root.u.def.section->owner) \
  73    && ((EH)->elf.root.u.def.section->owner->flags & DYNAMIC) != 0 \
  74    && ((EH)->elf.root.u.def.section->flags & SEC_CODE) == 0)
  75
  76 /* TRUE if dynamic relocation is needed.  If we are creating a shared
  77    library, and this is a reloc against a global symbol, or a non PC
  78    relative reloc against a local symbol, then we need to copy the reloc
  79    into the shared library.  However, if we are linking with -Bsymbolic,
  80    we do not need to copy a reloc against a global symbol which is
  81    defined in an object we are including in the link (i.e., DEF_REGULAR
  82    is set).
  83
  84    If PCREL_PLT is true, don't generate dynamic relocation in PIE for
  85    PC-relative relocation against a dynamic function definition in data
  86    section when PLT address can be used.
  87
  88    If on the other hand, we are creating an executable, we may need to
  89    keep relocations for symbols satisfied by a dynamic library if we
  90    manage to avoid copy relocs for the symbol.
  91
  92    We also need to generate dynamic pointer relocation against
  93    STT_GNU_IFUNC symbol in the non-code section.  */
  94 #define NEED_DYNAMIC_RELOCATION_P(INFO, PCREL_PLT, H, SEC, R_TYPE, \
  95                                   POINTER_TYPE) \
  96   ((bfd_link_pic (INFO) \
  97     && (! X86_PCREL_TYPE_P (R_TYPE) \
  98         || ((H) != NULL \
  99             && (! (bfd_link_pie (INFO) \
 100                    || SYMBOLIC_BIND ((INFO), (H))) \
 101                 || (H)->root.type == bfd_link_hash_defweak \
 102                 || (!(bfd_link_pie (INFO) \
 103                       && (PCREL_PLT) \
 104                       && (H)->plt.refcount > 0 \
 105                       && ((SEC)->flags & SEC_CODE) == 0 \
 106                       && (H)->type == STT_FUNC \
 107                       && (H)->def_dynamic) \
 108                     && !(H)->def_regular))))) \
 109    || ((H) != NULL \
 110        && (H)->type == STT_GNU_IFUNC \
 111        && (R_TYPE) == POINTER_TYPE \
 112        && ((SEC)->flags & SEC_CODE) == 0) \
 113    || (ELIMINATE_COPY_RELOCS \
 114        && !bfd_link_pic (INFO) \
 115        && (H) != NULL \
 116        && ((H)->root.type == bfd_link_hash_defweak \
 117            || !(H)->def_regular)))
 118
 119 /* TRUE if dynamic relocation should be generated.  Don't copy a
 120    pc-relative relocation into the output file if the symbol needs
 121    copy reloc or the symbol is undefined when building executable.
 122    Copy dynamic function pointer relocations.  Don't generate dynamic
 123    relocations against resolved undefined weak symbols in PIE, except
 124    when PC32_RELOC is TRUE.  Undefined weak symbol is bound locally
 125    when PIC is false.  Don't generate dynamic relocations against
 126    non-preemptible absolute symbol.  */
 127 #define GENERATE_DYNAMIC_RELOCATION_P(INFO, EH, R_TYPE, SEC, \
 128                                       NEED_COPY_RELOC_IN_PIE, \
 129                                       RESOLVED_TO_ZERO, PC32_RELOC) \
 130   ((bfd_link_pic (INFO) \
 131     && !(bfd_is_abs_section (SEC) \
 132          && ((EH) == NULL \
 133              || SYMBOL_REFERENCES_LOCAL (INFO, &(EH)->elf))) \
 134     && !(NEED_COPY_RELOC_IN_PIE) \
 135     && ((EH) == NULL \
 136         || ((ELF_ST_VISIBILITY ((EH)->elf.other) == STV_DEFAULT \
 137              && (!(RESOLVED_TO_ZERO) || PC32_RELOC)) \
 138             || (EH)->elf.root.type != bfd_link_hash_undefweak)) \
 139     && ((!X86_PCREL_TYPE_P (R_TYPE) && !X86_SIZE_TYPE_P (R_TYPE)) \
 140         || ! SYMBOL_CALLS_LOCAL ((INFO), \
 141                                  (struct elf_link_hash_entry *) (EH)))) \
 142    || (ELIMINATE_COPY_RELOCS \
 143        && !bfd_link_pic (INFO) \
 144        && (EH) != NULL \
 145        && (EH)->elf.dynindx != -1 \
 146        && (!(EH)->elf.non_got_ref \
 147            || ((EH)->elf.root.type == bfd_link_hash_undefweak \
 148                && !(RESOLVED_TO_ZERO))) \
 149                && (((EH)->elf.def_dynamic && !(EH)->elf.def_regular) \
 150                    || (EH)->elf.root.type == bfd_link_hash_undefined)))
 151
 152 /* TRUE if this input relocation should be copied to output.  H->dynindx
 153    may be -1 if this symbol was marked to become local.  */
 154 #define COPY_INPUT_RELOC_P(INFO, H, R_TYPE) \
 155   ((H) != NULL \
 156    && (H)->dynindx != -1 \
 157    && (X86_PCREL_TYPE_P (R_TYPE) \
 158        || !(bfd_link_executable (INFO) || SYMBOLIC_BIND ((INFO), (H))) \
 159        || !(H)->def_regular))
 160
 161 /* TRUE if this is actually a static link, or it is a -Bsymbolic link
 162    and the symbol is defined locally, or the symbol was forced to be
 163    local because of a version file.  */
 164 #define RESOLVED_LOCALLY_P(INFO, H, HTAB) \
 165   (!WILL_CALL_FINISH_DYNAMIC_SYMBOL ((HTAB)->elf.dynamic_sections_created, \
 166                                      bfd_link_pic (INFO), (H)) \
 167    || (bfd_link_pic (INFO) \
 168        && SYMBOL_REFERENCES_LOCAL_P ((INFO), (H))) \
 169        || (ELF_ST_VISIBILITY ((H)->other) \
 170            && (H)->root.type == bfd_link_hash_undefweak))
 171
 172 /* TRUE if this symbol isn't defined by a shared object.  */
 173 #define SYMBOL_DEFINED_NON_SHARED_P(H) \
 174   ((H)->def_regular \
 175    || (H)->root.linker_def \
 176    || (H)->root.ldscript_def \
 177    || ((struct elf_x86_link_hash_entry *) (H))->linker_def \
 178    || ELF_COMMON_DEF_P (H))
 179
 180 /* Return TRUE if the symbol described by a linker hash entry H is
 181    going to be absolute.  Similar to bfd_is_abs_symbol, but excluding
 182    all linker-script defined symbols.  */
 183 #define ABS_SYMBOL_P(H) \
 184   (bfd_is_abs_symbol (&(H)->root) && !(H)->root.ldscript_def)
 185
 186 /* TRUE if relative relocation should be generated.  GOT reference to
 187    global symbol in PIC will lead to dynamic symbol.  It becomes a
 188    problem when "time" or "times" is defined as a variable in an
 189    executable, clashing with functions of the same name in libc.  If a
 190    symbol isn't undefined weak symbol, don't make it dynamic in PIC and
 191    generate relative relocation.   Don't generate relative relocation
 192    against non-preemptible absolute symbol.  */
 193 #define GENERATE_RELATIVE_RELOC_P(INFO, H) \
 194   ((H)->dynindx == -1 \
 195    && !(H)->forced_local \
 196    && (H)->root.type != bfd_link_hash_undefweak \
 197    && bfd_link_pic (INFO) \
 198    && !ABS_SYMBOL_P (H))
 199
 200 /* TRUE if this is a pointer reference to a local IFUNC.  */
 201 #define POINTER_LOCAL_IFUNC_P(INFO, H) \
 202   ((H)->dynindx == -1 \
 203    || (H)->forced_local \
 204    || bfd_link_executable (INFO))
 205
 206 /* TRUE if this is a PLT reference to a local IFUNC.  */
 207 #define PLT_LOCAL_IFUNC_P(INFO, H) \
 208   ((H)->dynindx == -1 \
 209    || ((bfd_link_executable (INFO) \
 210         || ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT) \
 211         && (H)->def_regular \
 212         && (H)->type == STT_GNU_IFUNC))
 213
 214 /* TRUE if TLS IE->LE transition is OK.  */
 215 #define TLS_TRANSITION_IE_TO_LE_P(INFO, H, TLS_TYPE) \
 216   (bfd_link_executable (INFO) \
 217    && (H) != NULL \
 218    && (H)->dynindx == -1 \
 219    && (TLS_TYPE & GOT_TLS_IE))
 220
 221 /* Verify that the symbol has an entry in the procedure linkage table.  */
 222 #define VERIFY_PLT_ENTRY(INFO, H, PLT, GOTPLT, RELPLT, LOCAL_UNDEFWEAK) \
 223   do \
 224     { \
 225       if (((H)->dynindx == -1 \
 226            && !LOCAL_UNDEFWEAK \
 227            && !(((H)->forced_local || bfd_link_executable (INFO)) \
 228                 && (H)->def_regular \
 229                 && (H)->type == STT_GNU_IFUNC)) \
 230           || (PLT) == NULL \
 231           || (GOTPLT) == NULL \
 232           || (RELPLT) == NULL) \
 233         abort (); \
 234     } \
 235   while (0);
 236
 237 /* Verify that the symbol supports copy relocation.  */
 238 #define VERIFY_COPY_RELOC(H, HTAB) \
 239   do \
 240     { \
 241       if ((H)->dynindx == -1 \
 242           || ((H)->root.type != bfd_link_hash_defined \
 243               && (H)->root.type != bfd_link_hash_defweak) \
 244           || (HTAB)->elf.srelbss == NULL \
 245           || (HTAB)->elf.sreldynrelro == NULL) \
 246         abort (); \
 247     } \
 248   while (0);
 249
 250 /* x86 ELF linker hash entry.  */
 251
 252 struct elf_x86_link_hash_entry
 253 {
 254   struct elf_link_hash_entry elf;
 255
 256   unsigned char tls_type;
 257
 258   /* Bit 0: Symbol has no GOT nor PLT relocations.
 259      Bit 1: Symbol has non-GOT/non-PLT relocations in text sections.
 260      zero_undefweak is initialized to 1 and undefined weak symbol
 261      should be resolved to 0 if zero_undefweak > 0.  */
 262   unsigned int zero_undefweak : 2;
 263
 264   /* Don't call finish_dynamic_symbol on this symbol.  */
 265   unsigned int no_finish_dynamic_symbol : 1;
 266
 267   /* TRUE if symbol is __tls_get_addr.  */
 268   unsigned int tls_get_addr : 1;
 269
 270   /* TRUE if symbol is defined as a protected symbol.  */
 271   unsigned int def_protected : 1;
 272
 273   /* 0: Symbol references are unknown.
 274      1: Symbol references aren't local.
 275      2: Symbol references are local.
 276    */
 277   unsigned int local_ref : 2;
 278
 279   /* TRUE if symbol is defined by linker.  */
 280   unsigned int linker_def : 1;
 281
 282   /* TRUE if symbol is referenced by R_386_GOTOFF relocation.  This is
 283      only used by i386.  */
 284   unsigned int gotoff_ref : 1;
 285
 286   /* TRUE if a weak symbol with a real definition needs a copy reloc.
 287      When there is a weak symbol with a real definition, the processor
 288      independent code will have arranged for us to see the real
 289      definition first.  We need to copy the needs_copy bit from the
 290      real definition and check it when allowing copy reloc in PIE.  This
 291      is only used by x86-64.  */
 292   unsigned int needs_copy : 1;
 293
 294   /* Information about the GOT PLT entry. Filled when there are both
 295      GOT and PLT relocations against the same function.  */
 296   union gotplt_union plt_got;
 297
 298   /* Information about the second PLT entry.   */
 299   union gotplt_union plt_second;
 300
 301   /* Offset of the GOTPLT entry reserved for the TLS descriptor,
 302      starting at the end of the jump table.  */
 303   bfd_vma tlsdesc_got;
 304 };
 305
 306 struct elf_x86_lazy_plt_layout
 307 {
 308   /* The first entry in a lazy procedure linkage table looks like this.  */
 309   const bfd_byte *plt0_entry;
 310   unsigned int plt0_entry_size;          /* Size of PLT0 entry.  */
 311
 312   /* Later entries in a lazy procedure linkage table look like this.  */
 313   const bfd_byte *plt_entry;
 314   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 315
 316   /* The TLSDESC entry in a lazy procedure linkage table looks like
 317      this.  This is for x86-64 only.  */
 318   const bfd_byte *plt_tlsdesc_entry;
 319   unsigned int plt_tlsdesc_entry_size;   /* Size of TLSDESC entry.  */
 320
 321   /* Offsets into the TLSDESC entry that are to be replaced with
 322      GOT+8 and GOT+TDG.  These are for x86-64 only.  */
 323   unsigned int plt_tlsdesc_got1_offset;
 324   unsigned int plt_tlsdesc_got2_offset;
 325
 326   /* Offset of the end of the PC-relative instructions containing
 327      plt_tlsdesc_got1_offset and plt_tlsdesc_got2_offset.  These
 328      are for x86-64 only.  */
 329   unsigned int plt_tlsdesc_got1_insn_end;
 330   unsigned int plt_tlsdesc_got2_insn_end;
 331
 332   /* Offsets into plt0_entry that are to be replaced with GOT[1] and
 333      GOT[2].  */
 334   unsigned int plt0_got1_offset;
 335   unsigned int plt0_got2_offset;
 336
 337   /* Offset of the end of the PC-relative instruction containing
 338      plt0_got2_offset.  This is for x86-64 only.  */
 339   unsigned int plt0_got2_insn_end;
 340
 341   /* Offsets into plt_entry that are to be replaced with...  */
 342   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 343   unsigned int plt_reloc_offset;  /* ... offset into relocation table. */
 344   unsigned int plt_plt_offset;    /* ... offset to start of .plt. */
 345
 346   /* Length of the PC-relative instruction containing plt_got_offset.
 347      This is used for x86-64 only.  */
 348   unsigned int plt_got_insn_size;
 349
 350   /* Offset of the end of the PC-relative jump to plt0_entry.  This is
 351      used for x86-64 only.  */
 352   unsigned int plt_plt_insn_end;
 353
 354   /* Offset into plt_entry where the initial value of the GOT entry
 355      points.  */
 356   unsigned int plt_lazy_offset;
 357
 358   /* The first entry in a PIC lazy procedure linkage table looks like
 359      this.  */
 360   const bfd_byte *pic_plt0_entry;
 361
 362   /* Subsequent entries in a PIC lazy procedure linkage table look
 363      like this.  */
 364   const bfd_byte *pic_plt_entry;
 365
 366   /* .eh_frame covering the lazy .plt section.  */
 367   const bfd_byte *eh_frame_plt;
 368   unsigned int eh_frame_plt_size;
 369 };
 370
 371 struct elf_x86_non_lazy_plt_layout
 372 {
 373   /* Entries in a non-lazy procedure linkage table look like this.  */
 374   const bfd_byte *plt_entry;
 375   /* Entries in a PIC non-lazy procedure linkage table look like this.
 376      This is only used for i386 where absolute PLT and PIC PLT are
 377      different.  */
 378   const bfd_byte *pic_plt_entry;
 379
 380   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 381
 382   /* Offsets into plt_entry that are to be replaced with...  */
 383   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 384
 385   /* Length of the PC-relative instruction containing plt_got_offset.
 386      This is used for x86-64 only.  */
 387   unsigned int plt_got_insn_size;
 388
 389   /* .eh_frame covering the non-lazy .plt section.  */
 390   const bfd_byte *eh_frame_plt;
 391   unsigned int eh_frame_plt_size;
 392 };
 393
 394 struct elf_x86_plt_layout
 395 {
 396   /* The first entry in a lazy procedure linkage table looks like this.  */
 397   const bfd_byte *plt0_entry;
 398   /* Entries in a procedure linkage table look like this.  */
 399   const bfd_byte *plt_entry;
 400   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 401
 402   /* 1 has PLT0.  */
 403   unsigned int has_plt0;
 404
 405   /* Offsets into plt_entry that are to be replaced with...  */
 406   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 407
 408   /* Length of the PC-relative instruction containing plt_got_offset.
 409      This is only used for x86-64.  */
 410   unsigned int plt_got_insn_size;
 411
 412   /* Alignment of the .iplt section.  */
 413   unsigned int iplt_alignment;
 414
 415   /* .eh_frame covering the .plt section.  */
 416   const bfd_byte *eh_frame_plt;
 417   unsigned int eh_frame_plt_size;
 418 };
 419
 420 /* Values in tls_type of x86 ELF linker hash entry.  */
 421 #define GOT_UNKNOWN     0
 422 #define GOT_NORMAL      1
 423 #define GOT_TLS_GD      2
 424 #define GOT_TLS_IE      4
 425 #define GOT_TLS_IE_POS  5
 426 #define GOT_TLS_IE_NEG  6
 427 #define GOT_TLS_IE_BOTH 7
 428 #define GOT_TLS_GDESC   8
 429 #define GOT_ABS         9
 430 #define GOT_TLS_GD_BOTH_P(type) \
 431   ((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
 432 #define GOT_TLS_GD_P(type) \
 433   ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
 434 #define GOT_TLS_GDESC_P(type) \
 435   ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
 436 #define GOT_TLS_GD_ANY_P(type) \
 437   (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
 438
 439 #define elf_x86_hash_entry(ent) \
 440   ((struct elf_x86_link_hash_entry *)(ent))
 441
 442 /* x86 ELF linker hash table.  */
 443
 444 struct elf_x86_link_hash_table
 445 {
 446   struct elf_link_hash_table elf;
 447
 448   /* Short-cuts to get to dynamic linker sections.  */
 449   asection *interp;
 450   asection *plt_eh_frame;
 451   asection *plt_second;
 452   asection *plt_second_eh_frame;
 453   asection *plt_got;
 454   asection *plt_got_eh_frame;
 455
 456   /* Parameters describing PLT generation, lazy or non-lazy.  */
 457   struct elf_x86_plt_layout plt;
 458
 459   /* Parameters describing lazy PLT generation.  */
 460   const struct elf_x86_lazy_plt_layout *lazy_plt;
 461
 462   /* Parameters describing non-lazy PLT generation.  */
 463   const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
 464
 465   union
 466   {
 467     bfd_signed_vma refcount;
 468     bfd_vma offset;
 469   } tls_ld_or_ldm_got;
 470
 471   /* The amount of space used by the jump slots in the GOT.  */
 472   bfd_vma sgotplt_jump_table_size;
 473
 474   /* _TLS_MODULE_BASE_ symbol.  */
 475   struct bfd_link_hash_entry *tls_module_base;
 476
 477   /* Used by local STT_GNU_IFUNC symbols.  */
 478   htab_t loc_hash_table;
 479   void * loc_hash_memory;
 480
 481   /* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt.  */
 482   bfd_vma next_jump_slot_index;
 483   /* The index of the next R_X86_64_IRELATIVE entry in .rela.plt.  */
 484   bfd_vma next_irelative_index;
 485
 486   /* The (unloaded but important) .rel.plt.unloaded section on VxWorks.
 487      This is used for i386 only.  */
 488   asection *srelplt2;
 489
 490   /* The index of the next unused R_386_TLS_DESC slot in .rel.plt.  This
 491      is only used for i386.  */
 492   bfd_vma next_tls_desc_index;
 493
 494    /* Value used to fill the unused bytes of the first PLT entry.  This
 495       is only used for i386.  */
 496   bfd_byte plt0_pad_byte;
 497
 498   /* TRUE if GOT is referenced.  */
 499   unsigned int got_referenced : 1;
 500
 501   /* TRUE if PLT is PC-relative.  PLT in PDE and PC-relative PLT in PIE
 502      can be used as function address.
 503
 504      NB: i386 has non-PIC PLT and PIC PLT.  Only non-PIC PLT in PDE can
 505      be used as function address.  PIC PLT in PIE can't be used as
 506      function address.  */
 507   unsigned int pcrel_plt : 1;
 508
 509   bfd_vma (*r_info) (bfd_vma, bfd_vma);
 510   bfd_vma (*r_sym) (bfd_vma);
 511   bool (*is_reloc_section) (const char *);
 512   unsigned int sizeof_reloc;
 513   unsigned int got_entry_size;
 514   unsigned int pointer_r_type;
 515   int dynamic_interpreter_size;
 516   const char *dynamic_interpreter;
 517   const char *tls_get_addr;
 518
 519   /* Options passed from the linker.  */
 520   struct elf_linker_x86_params *params;
 521 };
 522
 523 struct elf_x86_init_table
 524 {
 525   /* The lazy PLT layout.  */
 526   const struct elf_x86_lazy_plt_layout *lazy_plt;
 527
 528   /* The non-lazy PLT layout.  */
 529   const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
 530
 531   /* The lazy PLT layout for IBT.  */
 532   const struct elf_x86_lazy_plt_layout *lazy_ibt_plt;
 533
 534   /* The non-lazy PLT layout for IBT.  */
 535   const struct elf_x86_non_lazy_plt_layout *non_lazy_ibt_plt;
 536
 537   bfd_byte plt0_pad_byte;
 538
 539   bfd_vma (*r_info) (bfd_vma, bfd_vma);
 540   bfd_vma (*r_sym) (bfd_vma);
 541 };
 542
 543 struct elf_x86_obj_tdata
 544 {
 545   struct elf_obj_tdata root;
 546
 547   /* tls_type for each local got entry.  */
 548   char *local_got_tls_type;
 549
 550   /* GOTPLT entries for TLS descriptors.  */
 551   bfd_vma *local_tlsdesc_gotent;
 552 };
 553
 554 enum elf_x86_plt_type
 555 {
 556   plt_non_lazy = 0,
 557   plt_lazy = 1 << 0,
 558   plt_pic = 1 << 1,
 559   plt_second = 1 << 2,
 560   plt_unknown = -1
 561 };
 562
 563 struct elf_x86_plt
 564 {
 565   const char *name;
 566   asection *sec;
 567   bfd_byte *contents;
 568   enum elf_x86_plt_type type;
 569   unsigned int plt_got_offset;
 570   unsigned int plt_entry_size;
 571   unsigned int plt_got_insn_size;       /* Only used for x86-64.  */
 572   long count;
 573 };
 574
 575 /* Set if a relocation is converted from a GOTPCREL relocation.  */
 576 #define R_X86_64_converted_reloc_bit (1 << 7)
 577
 578 #define elf_x86_tdata(abfd) \
 579   ((struct elf_x86_obj_tdata *) (abfd)->tdata.any)
 580
 581 #define elf_x86_local_got_tls_type(abfd) \
 582   (elf_x86_tdata (abfd)->local_got_tls_type)
 583
 584 #define elf_x86_local_tlsdesc_gotent(abfd) \
 585   (elf_x86_tdata (abfd)->local_tlsdesc_gotent)
 586
 587 #define elf_x86_compute_jump_table_size(htab) \
 588   ((htab)->elf.srelplt->reloc_count * (htab)->got_entry_size)
 589
 590 #define is_x86_elf(bfd, htab)                           \
 591   (bfd_get_flavour (bfd) == bfd_target_elf_flavour      \
 592    && elf_tdata (bfd) != NULL                           \
 593    && elf_object_id (bfd) == (htab)->elf.hash_table_id)
 594
 595 extern bool _bfd_x86_elf_mkobject
 596   (bfd *);
 597
 598 extern void _bfd_x86_elf_set_tls_module_base
 599   (struct bfd_link_info *);
 600
 601 extern bfd_vma _bfd_x86_elf_dtpoff_base
 602   (struct bfd_link_info *);
 603
 604 extern bool _bfd_x86_elf_readonly_dynrelocs
 605   (struct elf_link_hash_entry *, void *);
 606
 607 extern struct elf_link_hash_entry * _bfd_elf_x86_get_local_sym_hash
 608   (struct elf_x86_link_hash_table *, bfd *, const Elf_Internal_Rela *,
 609    bool);
 610
 611 extern hashval_t _bfd_x86_elf_local_htab_hash
 612   (const void *);
 613
 614 extern int _bfd_x86_elf_local_htab_eq
 615   (const void *, const void *);
 616
 617 extern struct bfd_hash_entry * _bfd_x86_elf_link_hash_newfunc
 618   (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
 619
 620 extern struct bfd_link_hash_table * _bfd_x86_elf_link_hash_table_create
 621   (bfd *);
 622
 623 extern int _bfd_x86_elf_compare_relocs
 624   (const void *, const void *);
 625
 626 extern bool _bfd_x86_elf_link_check_relocs
 627   (bfd *, struct bfd_link_info *);
 628
 629 extern bool _bfd_elf_x86_valid_reloc_p
 630   (asection *, struct bfd_link_info *, struct elf_x86_link_hash_table *,
 631    const Elf_Internal_Rela *, struct elf_link_hash_entry *,
 632    Elf_Internal_Sym *, Elf_Internal_Shdr *, bool *);
 633
 634 extern bool _bfd_x86_elf_size_dynamic_sections
 635   (bfd *, struct bfd_link_info *);
 636
 637 extern struct elf_x86_link_hash_table *_bfd_x86_elf_finish_dynamic_sections
 638   (bfd *, struct bfd_link_info *);
 639
 640 extern bool _bfd_x86_elf_always_size_sections
 641   (bfd *, struct bfd_link_info *);
 642
 643 extern void _bfd_x86_elf_merge_symbol_attribute
 644   (struct elf_link_hash_entry *, unsigned int, bool, bool);
 645
 646 extern void _bfd_x86_elf_copy_indirect_symbol
 647   (struct bfd_link_info *, struct elf_link_hash_entry *,
 648    struct elf_link_hash_entry *);
 649
 650 extern bool _bfd_x86_elf_fixup_symbol
 651   (struct bfd_link_info *, struct elf_link_hash_entry *);
 652
 653 extern bool _bfd_x86_elf_hash_symbol
 654   (struct elf_link_hash_entry *);
 655
 656 extern bool _bfd_x86_elf_adjust_dynamic_symbol
 657   (struct bfd_link_info *, struct elf_link_hash_entry *);
 658
 659 extern void _bfd_x86_elf_hide_symbol
 660   (struct bfd_link_info *, struct elf_link_hash_entry *, bool);
 661
 662 extern bool _bfd_x86_elf_link_symbol_references_local
 663   (struct bfd_link_info *, struct elf_link_hash_entry *);
 664
 665 extern asection * _bfd_x86_elf_gc_mark_hook
 666   (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
 667    struct elf_link_hash_entry *, Elf_Internal_Sym *);
 668
 669 extern long _bfd_x86_elf_get_synthetic_symtab
 670   (bfd *, long, long, bfd_vma, struct elf_x86_plt [], asymbol **,
 671    asymbol **);
 672
 673 extern enum elf_property_kind _bfd_x86_elf_parse_gnu_properties
 674   (bfd *, unsigned int, bfd_byte *, unsigned int);
 675
 676 extern bool _bfd_x86_elf_merge_gnu_properties
 677   (struct bfd_link_info *, bfd *, bfd *, elf_property *, elf_property *);
 678
 679 extern void _bfd_x86_elf_link_fixup_gnu_properties
 680   (struct bfd_link_info *, elf_property_list **);
 681
 682 extern bfd * _bfd_x86_elf_link_setup_gnu_properties
 683   (struct bfd_link_info *, struct elf_x86_init_table *);
 684
 685 extern void _bfd_x86_elf_link_fixup_ifunc_symbol
 686   (struct bfd_link_info *, struct elf_x86_link_hash_table *,
 687    struct elf_link_hash_entry *, Elf_Internal_Sym *sym);
 688
 689 extern void _bfd_x86_elf_link_report_relative_reloc
 690   (struct bfd_link_info *, asection *, struct elf_link_hash_entry *,
 691    Elf_Internal_Sym *, const char *, const void *);
 692
 693 #define bfd_elf64_mkobject \
 694   _bfd_x86_elf_mkobject
 695 #define bfd_elf32_mkobject \
 696   _bfd_x86_elf_mkobject
 697 #define bfd_elf64_bfd_link_hash_table_create \
 698   _bfd_x86_elf_link_hash_table_create
 699 #define bfd_elf32_bfd_link_hash_table_create \
 700   _bfd_x86_elf_link_hash_table_create
 701 #define bfd_elf64_bfd_link_check_relocs \
 702   _bfd_x86_elf_link_check_relocs
 703 #define bfd_elf32_bfd_link_check_relocs \
 704   _bfd_x86_elf_link_check_relocs
 705
 706 #define elf_backend_size_dynamic_sections \
 707   _bfd_x86_elf_size_dynamic_sections
 708 #define elf_backend_always_size_sections \
 709   _bfd_x86_elf_always_size_sections
 710 #define elf_backend_merge_symbol_attribute \
 711   _bfd_x86_elf_merge_symbol_attribute
 712 #define elf_backend_copy_indirect_symbol \
 713   _bfd_x86_elf_copy_indirect_symbol
 714 #define elf_backend_fixup_symbol \
 715   _bfd_x86_elf_fixup_symbol
 716 #define elf_backend_hash_symbol \
 717   _bfd_x86_elf_hash_symbol
 718 #define elf_backend_adjust_dynamic_symbol \
 719   _bfd_x86_elf_adjust_dynamic_symbol
 720 #define elf_backend_gc_mark_hook \
 721   _bfd_x86_elf_gc_mark_hook
 722 #define elf_backend_omit_section_dynsym \
 723   _bfd_elf_omit_section_dynsym_all
 724 #define elf_backend_parse_gnu_properties \
 725   _bfd_x86_elf_parse_gnu_properties
 726 #define elf_backend_merge_gnu_properties \
 727   _bfd_x86_elf_merge_gnu_properties
 728 #define elf_backend_fixup_gnu_properties \
 729   _bfd_x86_elf_link_fixup_gnu_properties