bfd/elfxx-x86.h

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