bfd/elfxx-x86.h

   1 /* x86 specific support for ELF
   2    Copyright (C) 2017-2019 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 "hashtab.h"
  27
  28 #define PLT_CIE_LENGTH          20
  29 #define PLT_FDE_LENGTH          36
  30 #define PLT_FDE_START_OFFSET    4 + PLT_CIE_LENGTH + 8
  31 #define PLT_FDE_LEN_OFFSET      4 + PLT_CIE_LENGTH + 12
  32
  33 #define ABI_64_P(abfd) \
  34   (get_elf_backend_data (abfd)->s->elfclass == ELFCLASS64)
  35
  36 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
  37    copying dynamic variables from a shared lib into an app's dynbss
  38    section, and instead use a dynamic relocation to point into the
  39    shared lib.  */
  40 #define ELIMINATE_COPY_RELOCS 1
  41
  42 #define elf_x86_hash_table(p, id) \
  43   (is_elf_hash_table ((p)->hash) \
  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 /* Will references to this symbol always be local in this object?  */
  48 #define SYMBOL_REFERENCES_LOCAL_P(INFO, H) \
  49   _bfd_x86_elf_link_symbol_references_local ((INFO), (H))
  50
  51 /* TRUE if an undefined weak symbol should be resolved to 0.  Local
  52    undefined weak symbol is always resolved to 0.  Reference to an
  53    undefined weak symbol is resolved to 0 in executable if undefined
  54    weak symbol should be resolved to 0 (zero_undefweak > 0).  */
  55 #define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, EH) \
  56   ((EH)->elf.root.type == bfd_link_hash_undefweak                \
  57    && (SYMBOL_REFERENCES_LOCAL_P ((INFO), &(EH)->elf)            \
  58        || (bfd_link_executable (INFO)                            \
  59            && (EH)->zero_undefweak > 0)))
  60
  61 /* Should copy relocation be generated for a symbol.  Don't generate
  62    copy relocation against a protected symbol defined in a shared
  63    object with GNU_PROPERTY_NO_COPY_ON_PROTECTED.  */
  64 #define SYMBOL_NO_COPYRELOC(INFO, EH) \
  65   ((EH)->def_protected \
  66    && ((EH)->elf.root.type == bfd_link_hash_defined \
  67        || (EH)->elf.root.type == bfd_link_hash_defweak) \
  68    && elf_has_no_copy_on_protected ((EH)->elf.root.u.def.section->owner) \
  69    && ((EH)->elf.root.u.def.section->owner->flags & DYNAMIC) != 0 \
  70    && ((EH)->elf.root.u.def.section->flags & SEC_CODE) == 0)
  71
  72 /* TRUE if dynamic relocation is needed.  If we are creating a shared
  73    library, and this is a reloc against a global symbol, or a non PC
  74    relative reloc against a local symbol, then we need to copy the reloc
  75    into the shared library.  However, if we are linking with -Bsymbolic,
  76    we do not need to copy a reloc against a global symbol which is
  77    defined in an object we are including in the link (i.e., DEF_REGULAR
  78    is set).
  79
  80    If PCREL_PLT is true, don't generate dynamic relocation in PIE for
  81    PC-relative relocation against a dynamic function definition in data
  82    section when PLT address can be used.
  83
  84    If on the other hand, we are creating an executable, we may need to
  85    keep relocations for symbols satisfied by a dynamic library if we
  86    manage to avoid copy relocs for the symbol.
  87
  88    We also need to generate dynamic pointer relocation against
  89    STT_GNU_IFUNC symbol in the non-code section.  */
  90 #define NEED_DYNAMIC_RELOCATION_P(INFO, PCREL_PLT, H, SEC, R_TYPE, \
  91                                   POINTER_TYPE) \
  92   ((bfd_link_pic (INFO) \
  93     && (! X86_PCREL_TYPE_P (R_TYPE) \
  94         || ((H) != NULL \
  95             && (! (bfd_link_pie (INFO) \
  96                    || SYMBOLIC_BIND ((INFO), (H))) \
  97                 || (H)->root.type == bfd_link_hash_defweak \
  98                 || (!(bfd_link_pie (INFO) \
  99                       && (PCREL_PLT) \
 100                       && (H)->plt.refcount > 0 \
 101                       && ((SEC)->flags & SEC_CODE) == 0 \
 102                       && (H)->type == STT_FUNC \
 103                       && (H)->def_dynamic) \
 104                     && !(H)->def_regular))))) \
 105    || ((H) != NULL \
 106        && (H)->type == STT_GNU_IFUNC \
 107        && (R_TYPE) == POINTER_TYPE \
 108        && ((SEC)->flags & SEC_CODE) == 0) \
 109    || (ELIMINATE_COPY_RELOCS \
 110        && !bfd_link_pic (INFO) \
 111        && (H) != NULL \
 112        && ((H)->root.type == bfd_link_hash_defweak \
 113            || !(H)->def_regular)))
 114
 115 /* TRUE if dynamic relocation should be generated.  Don't copy a
 116    pc-relative relocation into the output file if the symbol needs
 117    copy reloc or the symbol is undefined when building executable.
 118    Copy dynamic function pointer relocations.  Don't generate dynamic
 119    relocations against resolved undefined weak symbols in PIE, except
 120    when PC32_RELOC is TRUE.  Undefined weak symbol is bound locally
 121    when PIC is false.  */
 122 #define GENERATE_DYNAMIC_RELOCATION_P(INFO, EH, R_TYPE, \
 123                                       NEED_COPY_RELOC_IN_PIE, \
 124                                       RESOLVED_TO_ZERO, PC32_RELOC) \
 125   ((bfd_link_pic (INFO) \
 126     && !(NEED_COPY_RELOC_IN_PIE) \
 127     && ((EH) == NULL \
 128         || ((ELF_ST_VISIBILITY ((EH)->elf.other) == STV_DEFAULT \
 129              && (!(RESOLVED_TO_ZERO) || PC32_RELOC)) \
 130             || (EH)->elf.root.type != bfd_link_hash_undefweak)) \
 131     && ((!X86_PCREL_TYPE_P (R_TYPE) \
 132          && !X86_SIZE_TYPE_P (R_TYPE)) \
 133          || ! SYMBOL_CALLS_LOCAL ((INFO), &(EH)->elf))) \
 134    || (ELIMINATE_COPY_RELOCS \
 135        && !bfd_link_pic (INFO) \
 136        && (EH) != NULL \
 137        && (EH)->elf.dynindx != -1 \
 138        && (!(EH)->elf.non_got_ref \
 139            || ((EH)->elf.root.type == bfd_link_hash_undefweak \
 140                && !(RESOLVED_TO_ZERO))) \
 141                && (((EH)->elf.def_dynamic && !(EH)->elf.def_regular) \
 142                    || (EH)->elf.root.type == bfd_link_hash_undefined)))
 143
 144 /* TRUE if this input relocation should be copied to output.  H->dynindx
 145    may be -1 if this symbol was marked to become local.  */
 146 #define COPY_INPUT_RELOC_P(INFO, H, R_TYPE) \
 147   ((H) != NULL \
 148    && (H)->dynindx != -1 \
 149    && (X86_PCREL_TYPE_P (R_TYPE) \
 150        || !(bfd_link_executable (INFO) || SYMBOLIC_BIND ((INFO), (H))) \
 151        || !(H)->def_regular))
 152
 153 /* TRUE if this is actually a static link, or it is a -Bsymbolic link
 154    and the symbol is defined locally, or the symbol was forced to be
 155    local because of a version file.  */
 156 #define RESOLVED_LOCALLY_P(INFO, H, HTAB) \
 157   (!WILL_CALL_FINISH_DYNAMIC_SYMBOL ((HTAB)->elf.dynamic_sections_created, \
 158                                      bfd_link_pic (INFO), (H)) \
 159    || (bfd_link_pic (INFO) \
 160        && SYMBOL_REFERENCES_LOCAL_P ((INFO), (H))) \
 161        || (ELF_ST_VISIBILITY ((H)->other) \
 162            && (H)->root.type == bfd_link_hash_undefweak))
 163
 164 /* TRUE if this symbol isn't defined by a shared object.  */
 165 #define SYMBOL_DEFINED_NON_SHARED_P(H) \
 166   ((H)->def_regular \
 167    || (H)->root.linker_def \
 168    || (H)->root.ldscript_def \
 169    || ELF_COMMON_DEF_P (H))
 170
 171 /* TRUE if relative relocation should be generated.  GOT reference to
 172    global symbol in PIC will lead to dynamic symbol.  It becomes a
 173    problem when "time" or "times" is defined as a variable in an
 174    executable, clashing with functions of the same name in libc.  If a
 175    symbol isn't undefined weak symbol, don't make it dynamic in PIC and
 176    generate relative relocation.  */
 177 #define GENERATE_RELATIVE_RELOC_P(INFO, H) \
 178   ((H)->dynindx == -1 \
 179    && !(H)->forced_local \
 180    && (H)->root.type != bfd_link_hash_undefweak \
 181    && bfd_link_pic (INFO))
 182
 183 /* TRUE if this is a pointer reference to a local IFUNC.  */
 184 #define POINTER_LOCAL_IFUNC_P(INFO, H) \
 185   ((H)->dynindx == -1 \
 186    || (H)->forced_local \
 187    || bfd_link_executable (INFO))
 188
 189 /* TRUE if this is a PLT reference to a local IFUNC.  */
 190 #define PLT_LOCAL_IFUNC_P(INFO, H) \
 191   ((H)->dynindx == -1 \
 192    || ((bfd_link_executable (INFO) \
 193         || ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT) \
 194         && (H)->def_regular \
 195         && (H)->type == STT_GNU_IFUNC))
 196
 197 /* TRUE if TLS IE->LE transition is OK.  */
 198 #define TLS_TRANSITION_IE_TO_LE_P(INFO, H, TLS_TYPE) \
 199   (bfd_link_executable (INFO) \
 200    && (H) != NULL \
 201    && (H)->dynindx == -1 \
 202    && (TLS_TYPE & GOT_TLS_IE))
 203
 204 /* Verify that the symbol has an entry in the procedure linkage table.  */
 205 #define VERIFY_PLT_ENTRY(INFO, H, PLT, GOTPLT, RELPLT, LOCAL_UNDEFWEAK) \
 206   do \
 207     { \
 208       if (((H)->dynindx == -1 \
 209            && !LOCAL_UNDEFWEAK \
 210            && !(((H)->forced_local || bfd_link_executable (INFO)) \
 211                 && (H)->def_regular \
 212                 && (H)->type == STT_GNU_IFUNC)) \
 213           || (PLT) == NULL \
 214           || (GOTPLT) == NULL \
 215           || (RELPLT) == NULL) \
 216         abort (); \
 217     } \
 218   while (0);
 219
 220 /* Verify that the symbol supports copy relocation.  */
 221 #define VERIFY_COPY_RELOC(H, HTAB) \
 222   do \
 223     { \
 224       if ((H)->dynindx == -1 \
 225           || ((H)->root.type != bfd_link_hash_defined \
 226               && (H)->root.type != bfd_link_hash_defweak) \
 227           || (HTAB)->elf.srelbss == NULL \
 228           || (HTAB)->elf.sreldynrelro == NULL) \
 229         abort (); \
 230     } \
 231   while (0);
 232
 233 /* x86 ELF linker hash entry.  */
 234
 235 struct elf_x86_link_hash_entry
 236 {
 237   struct elf_link_hash_entry elf;
 238
 239   /* Track dynamic relocs copied for this symbol.  */
 240   struct elf_dyn_relocs *dyn_relocs;
 241
 242   unsigned char tls_type;
 243
 244   /* Bit 0: Symbol has no GOT nor PLT relocations.
 245      Bit 1: Symbol has non-GOT/non-PLT relocations in text sections.
 246      zero_undefweak is initialized to 1 and undefined weak symbol
 247      should be resolved to 0 if zero_undefweak > 0.  */
 248   unsigned int zero_undefweak : 2;
 249
 250   /* Don't call finish_dynamic_symbol on this symbol.  */
 251   unsigned int no_finish_dynamic_symbol : 1;
 252
 253   /* TRUE if symbol is __tls_get_addr.  */
 254   unsigned int tls_get_addr : 1;
 255
 256   /* TRUE if symbol is defined as a protected symbol.  */
 257   unsigned int def_protected : 1;
 258
 259   /* 0: Symbol references are unknown.
 260      1: Symbol references aren't local.
 261      2: Symbol references are local.
 262    */
 263   unsigned int local_ref : 2;
 264
 265   /* TRUE if symbol is defined by linker.  */
 266   unsigned int linker_def : 1;
 267
 268   /* TRUE if symbol is referenced by R_386_GOTOFF relocation.  This is
 269      only used by i386.  */
 270   unsigned int gotoff_ref : 1;
 271
 272   /* TRUE if a weak symbol with a real definition needs a copy reloc.
 273      When there is a weak symbol with a real definition, the processor
 274      independent code will have arranged for us to see the real
 275      definition first.  We need to copy the needs_copy bit from the
 276      real definition and check it when allowing copy reloc in PIE.  This
 277      is only used by x86-64.  */
 278   unsigned int needs_copy : 1;
 279
 280   /* Information about the GOT PLT entry. Filled when there are both
 281      GOT and PLT relocations against the same function.  */
 282   union gotplt_union plt_got;
 283
 284   /* Information about the second PLT entry.   */
 285   union gotplt_union plt_second;
 286
 287   /* Offset of the GOTPLT entry reserved for the TLS descriptor,
 288      starting at the end of the jump table.  */
 289   bfd_vma tlsdesc_got;
 290 };
 291
 292 struct elf_x86_lazy_plt_layout
 293 {
 294   /* The first entry in a lazy procedure linkage table looks like this.  */
 295   const bfd_byte *plt0_entry;
 296   unsigned int plt0_entry_size;          /* Size of PLT0 entry.  */
 297
 298   /* Later entries in a lazy procedure linkage table look like this.  */
 299   const bfd_byte *plt_entry;
 300   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 301
 302   /* The TLSDESC entry in a lazy procedure linkage table looks like
 303      this.  This is for x86-64 only.  */
 304   const bfd_byte *plt_tlsdesc_entry;
 305   unsigned int plt_tlsdesc_entry_size;   /* Size of TLSDESC entry.  */
 306
 307   /* Offsets into the TLSDESC entry that are to be replaced with
 308      GOT+8 and GOT+TDG.  These are for x86-64 only.  */
 309   unsigned int plt_tlsdesc_got1_offset;
 310   unsigned int plt_tlsdesc_got2_offset;
 311
 312   /* Offset of the end of the PC-relative instructions containing
 313      plt_tlsdesc_got1_offset and plt_tlsdesc_got2_offset.  These
 314      are for x86-64 only.  */
 315   unsigned int plt_tlsdesc_got1_insn_end;
 316   unsigned int plt_tlsdesc_got2_insn_end;
 317
 318   /* Offsets into plt0_entry that are to be replaced with GOT[1] and
 319      GOT[2].  */
 320   unsigned int plt0_got1_offset;
 321   unsigned int plt0_got2_offset;
 322
 323   /* Offset of the end of the PC-relative instruction containing
 324      plt0_got2_offset.  This is for x86-64 only.  */
 325   unsigned int plt0_got2_insn_end;
 326
 327   /* Offsets into plt_entry that are to be replaced with...  */
 328   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 329   unsigned int plt_reloc_offset;  /* ... offset into relocation table. */
 330   unsigned int plt_plt_offset;    /* ... offset to start of .plt. */
 331
 332   /* Length of the PC-relative instruction containing plt_got_offset.
 333      This is used for x86-64 only.  */
 334   unsigned int plt_got_insn_size;
 335
 336   /* Offset of the end of the PC-relative jump to plt0_entry.  This is
 337      used for x86-64 only.  */
 338   unsigned int plt_plt_insn_end;
 339
 340   /* Offset into plt_entry where the initial value of the GOT entry
 341      points.  */
 342   unsigned int plt_lazy_offset;
 343
 344   /* The first entry in a PIC lazy procedure linkage table looks like
 345      this.  */
 346   const bfd_byte *pic_plt0_entry;
 347
 348   /* Subsequent entries in a PIC lazy procedure linkage table look
 349      like this.  */
 350   const bfd_byte *pic_plt_entry;
 351
 352   /* .eh_frame covering the lazy .plt section.  */
 353   const bfd_byte *eh_frame_plt;
 354   unsigned int eh_frame_plt_size;
 355 };
 356
 357 struct elf_x86_non_lazy_plt_layout
 358 {
 359   /* Entries in a non-lazy procedure linkage table look like this.  */
 360   const bfd_byte *plt_entry;
 361   /* Entries in a PIC non-lazy procedure linkage table look like this.
 362      This is only used for i386 where absolute PLT and PIC PLT are
 363      different.  */
 364   const bfd_byte *pic_plt_entry;
 365
 366   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 367
 368   /* Offsets into plt_entry that are to be replaced with...  */
 369   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 370
 371   /* Length of the PC-relative instruction containing plt_got_offset.
 372      This is used for x86-64 only.  */
 373   unsigned int plt_got_insn_size;
 374
 375   /* .eh_frame covering the non-lazy .plt section.  */
 376   const bfd_byte *eh_frame_plt;
 377   unsigned int eh_frame_plt_size;
 378 };
 379
 380 struct elf_x86_plt_layout
 381 {
 382   /* The first entry in a lazy procedure linkage table looks like this.  */
 383   const bfd_byte *plt0_entry;
 384   /* Entries in a procedure linkage table look like this.  */
 385   const bfd_byte *plt_entry;
 386   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 387
 388   /* 1 has PLT0.  */
 389   unsigned int has_plt0;
 390
 391   /* Offsets into plt_entry that are to be replaced with...  */
 392   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 393
 394   /* Length of the PC-relative instruction containing plt_got_offset.
 395      This is only used for x86-64.  */
 396   unsigned int plt_got_insn_size;
 397
 398   /* Alignment of the .iplt section.  */
 399   unsigned int iplt_alignment;
 400
 401   /* .eh_frame covering the .plt section.  */
 402   const bfd_byte *eh_frame_plt;
 403   unsigned int eh_frame_plt_size;
 404 };
 405
 406 /* Values in tls_type of x86 ELF linker hash entry.  */
 407 #define GOT_UNKNOWN     0
 408 #define GOT_NORMAL      1
 409 #define GOT_TLS_GD      2
 410 #define GOT_TLS_IE      4
 411 #define GOT_TLS_IE_POS  5
 412 #define GOT_TLS_IE_NEG  6
 413 #define GOT_TLS_IE_BOTH 7
 414 #define GOT_TLS_GDESC   8
 415 #define GOT_TLS_GD_BOTH_P(type) \
 416   ((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
 417 #define GOT_TLS_GD_P(type) \
 418   ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
 419 #define GOT_TLS_GDESC_P(type) \
 420   ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
 421 #define GOT_TLS_GD_ANY_P(type) \
 422   (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
 423
 424 #define elf_x86_hash_entry(ent) \
 425   ((struct elf_x86_link_hash_entry *)(ent))
 426
 427 enum elf_x86_target_os
 428 {
 429   is_normal,
 430   is_solaris,
 431   is_vxworks,
 432   is_nacl
 433 };
 434
 435 /* x86 ELF linker hash table.  */
 436
 437 struct elf_x86_link_hash_table
 438 {
 439   struct elf_link_hash_table elf;
 440
 441   /* Short-cuts to get to dynamic linker sections.  */
 442   asection *interp;
 443   asection *plt_eh_frame;
 444   asection *plt_second;
 445   asection *plt_second_eh_frame;
 446   asection *plt_got;
 447   asection *plt_got_eh_frame;
 448
 449   /* Parameters describing PLT generation, lazy or non-lazy.  */
 450   struct elf_x86_plt_layout plt;
 451
 452   /* Parameters describing lazy PLT generation.  */
 453   const struct elf_x86_lazy_plt_layout *lazy_plt;
 454
 455   /* Parameters describing non-lazy PLT generation.  */
 456   const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
 457
 458   union
 459   {
 460     bfd_signed_vma refcount;
 461     bfd_vma offset;
 462   } tls_ld_or_ldm_got;
 463
 464   /* The amount of space used by the jump slots in the GOT.  */
 465   bfd_vma sgotplt_jump_table_size;
 466
 467   /* Small local sym cache.  */
 468   struct sym_cache sym_cache;
 469
 470   /* _TLS_MODULE_BASE_ symbol.  */
 471   struct bfd_link_hash_entry *tls_module_base;
 472
 473   /* Used by local STT_GNU_IFUNC symbols.  */
 474   htab_t loc_hash_table;
 475   void * loc_hash_memory;
 476
 477   /* The offset into sgot of the GOT entry used by the PLT entry
 478      above.  */
 479   bfd_vma tlsdesc_got;
 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   /* TRUE if there are dynamic relocs against IFUNC symbols that apply
 487      to read-only sections.  */
 488   bfd_boolean readonly_dynrelocs_against_ifunc;
 489
 490   /* The (unloaded but important) .rel.plt.unloaded section on VxWorks.
 491      This is used for i386 only.  */
 492   asection *srelplt2;
 493
 494   /* The index of the next unused R_386_TLS_DESC slot in .rel.plt.  This
 495      is only used for i386.  */
 496   bfd_vma next_tls_desc_index;
 497
 498   /* The offset into splt of the PLT entry for the TLS descriptor
 499      resolver.  Special values are 0, if not necessary (or not found
 500      to be necessary yet), and -1 if needed but not determined
 501      yet.  This is only used for x86-64.  */
 502   bfd_vma tlsdesc_plt;
 503
 504    /* Value used to fill the unused bytes of the first PLT entry.  This
 505       is only used for i386.  */
 506   bfd_byte plt0_pad_byte;
 507
 508   /* TRUE if GOT is referenced.  */
 509   unsigned int got_referenced : 1;
 510
 511   /* TRUE if PLT is PC-relative.  PLT in PDE and PC-relative PLT in PIE
 512      can be used as function address.
 513
 514      NB: i386 has non-PIC PLT and PIC PLT.  Only non-PIC PLT in PDE can
 515      be used as function address.  PIC PLT in PIE can't be used as
 516      function address.  */
 517   unsigned int pcrel_plt : 1;
 518
 519   bfd_vma (*r_info) (bfd_vma, bfd_vma);
 520   bfd_vma (*r_sym) (bfd_vma);
 521   bfd_boolean (*is_reloc_section) (const char *);
 522   enum elf_target_id target_id;
 523   enum elf_x86_target_os target_os;
 524   unsigned int sizeof_reloc;
 525   unsigned int dt_reloc;
 526   unsigned int dt_reloc_sz;
 527   unsigned int dt_reloc_ent;
 528   unsigned int got_entry_size;
 529   unsigned int pointer_r_type;
 530   int dynamic_interpreter_size;
 531   const char *dynamic_interpreter;
 532   const char *tls_get_addr;
 533 };
 534
 535 /* Architecture-specific backend data for x86.  */
 536
 537 struct elf_x86_backend_data
 538 {
 539   /* Target system.  */
 540   enum elf_x86_target_os target_os;
 541 };
 542
 543 #define get_elf_x86_backend_data(abfd) \
 544   ((const struct elf_x86_backend_data *) \
 545    get_elf_backend_data (abfd)->arch_data)
 546
 547 struct elf_x86_init_table
 548 {
 549   /* The lazy PLT layout.  */
 550   const struct elf_x86_lazy_plt_layout *lazy_plt;
 551
 552   /* The non-lazy PLT layout.  */
 553   const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
 554
 555   /* The lazy PLT layout for IBT.  */
 556   const struct elf_x86_lazy_plt_layout *lazy_ibt_plt;
 557
 558   /* The non-lazy PLT layout for IBT.  */
 559   const struct elf_x86_non_lazy_plt_layout *non_lazy_ibt_plt;
 560
 561   bfd_byte plt0_pad_byte;
 562
 563   bfd_vma (*r_info) (bfd_vma, bfd_vma);
 564   bfd_vma (*r_sym) (bfd_vma);
 565 };
 566
 567 struct elf_x86_obj_tdata
 568 {
 569   struct elf_obj_tdata root;
 570
 571   /* tls_type for each local got entry.  */
 572   char *local_got_tls_type;
 573
 574   /* GOTPLT entries for TLS descriptors.  */
 575   bfd_vma *local_tlsdesc_gotent;
 576 };
 577
 578 enum elf_x86_plt_type
 579 {
 580   plt_non_lazy = 0,
 581   plt_lazy = 1 << 0,
 582   plt_pic = 1 << 1,
 583   plt_second = 1 << 2,
 584   plt_unknown = -1
 585 };
 586
 587 struct elf_x86_plt
 588 {
 589   const char *name;
 590   asection *sec;
 591   bfd_byte *contents;
 592   enum elf_x86_plt_type type;
 593   unsigned int plt_got_offset;
 594   unsigned int plt_entry_size;
 595   unsigned int plt_got_insn_size;       /* Only used for x86-64.  */
 596   long count;
 597 };
 598
 599 #define elf_x86_tdata(abfd) \
 600   ((struct elf_x86_obj_tdata *) (abfd)->tdata.any)
 601
 602 #define elf_x86_local_got_tls_type(abfd) \
 603   (elf_x86_tdata (abfd)->local_got_tls_type)
 604
 605 #define elf_x86_local_tlsdesc_gotent(abfd) \
 606   (elf_x86_tdata (abfd)->local_tlsdesc_gotent)
 607
 608 #define elf_x86_compute_jump_table_size(htab) \
 609   ((htab)->elf.srelplt->reloc_count * (htab)->got_entry_size)
 610
 611 #define is_x86_elf(bfd, htab)                           \
 612   (bfd_get_flavour (bfd) == bfd_target_elf_flavour      \
 613    && elf_tdata (bfd) != NULL                           \
 614    && elf_object_id (bfd) == (htab)->target_id)
 615
 616 extern bfd_boolean _bfd_x86_elf_mkobject
 617   (bfd *);
 618
 619 extern void _bfd_x86_elf_set_tls_module_base
 620   (struct bfd_link_info *);
 621
 622 extern bfd_vma _bfd_x86_elf_dtpoff_base
 623   (struct bfd_link_info *);
 624
 625 extern bfd_boolean _bfd_x86_elf_readonly_dynrelocs
 626   (struct elf_link_hash_entry *, void *);
 627
 628 extern struct elf_link_hash_entry * _bfd_elf_x86_get_local_sym_hash
 629   (struct elf_x86_link_hash_table *, bfd *, const Elf_Internal_Rela *,
 630    bfd_boolean);
 631
 632 extern hashval_t _bfd_x86_elf_local_htab_hash
 633   (const void *);
 634
 635 extern int _bfd_x86_elf_local_htab_eq
 636   (const void *, const void *);
 637
 638 extern struct bfd_hash_entry * _bfd_x86_elf_link_hash_newfunc
 639   (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
 640
 641 extern struct bfd_link_hash_table * _bfd_x86_elf_link_hash_table_create
 642   (bfd *);
 643
 644 extern int _bfd_x86_elf_compare_relocs
 645   (const void *, const void *);
 646
 647 extern bfd_boolean _bfd_x86_elf_link_check_relocs
 648   (bfd *, struct bfd_link_info *);
 649
 650 extern bfd_boolean _bfd_x86_elf_size_dynamic_sections
 651   (bfd *, struct bfd_link_info *);
 652
 653 extern struct elf_x86_link_hash_table *_bfd_x86_elf_finish_dynamic_sections
 654   (bfd *, struct bfd_link_info *);
 655
 656 extern bfd_boolean _bfd_x86_elf_always_size_sections
 657   (bfd *, struct bfd_link_info *);
 658
 659 extern void _bfd_x86_elf_merge_symbol_attribute
 660   (struct elf_link_hash_entry *, const Elf_Internal_Sym *,
 661    bfd_boolean, bfd_boolean);
 662
 663 extern void _bfd_x86_elf_copy_indirect_symbol
 664   (struct bfd_link_info *, struct elf_link_hash_entry *,
 665    struct elf_link_hash_entry *);
 666
 667 extern bfd_boolean _bfd_x86_elf_fixup_symbol
 668   (struct bfd_link_info *, struct elf_link_hash_entry *);
 669
 670 extern bfd_boolean _bfd_x86_elf_hash_symbol
 671   (struct elf_link_hash_entry *);
 672
 673 extern bfd_boolean _bfd_x86_elf_adjust_dynamic_symbol
 674   (struct bfd_link_info *, struct elf_link_hash_entry *);
 675
 676 extern void _bfd_x86_elf_hide_symbol
 677   (struct bfd_link_info *, struct elf_link_hash_entry *, bfd_boolean);
 678
 679 extern bfd_boolean _bfd_x86_elf_link_symbol_references_local
 680   (struct bfd_link_info *, struct elf_link_hash_entry *);
 681
 682 extern asection * _bfd_x86_elf_gc_mark_hook
 683   (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
 684    struct elf_link_hash_entry *, Elf_Internal_Sym *);
 685
 686 extern long _bfd_x86_elf_get_synthetic_symtab
 687   (bfd *, long, long, bfd_vma, struct elf_x86_plt [], asymbol **,
 688    asymbol **);
 689
 690 extern enum elf_property_kind _bfd_x86_elf_parse_gnu_properties
 691   (bfd *, unsigned int, bfd_byte *, unsigned int);
 692
 693 extern bfd_boolean _bfd_x86_elf_merge_gnu_properties
 694   (struct bfd_link_info *, bfd *, elf_property *, elf_property *);
 695
 696 extern void _bfd_x86_elf_link_fixup_gnu_properties
 697   (struct bfd_link_info *, elf_property_list **);
 698
 699 extern bfd * _bfd_x86_elf_link_setup_gnu_properties
 700   (struct bfd_link_info *, struct elf_x86_init_table *);
 701
 702 extern void _bfd_x86_elf_link_fixup_ifunc_symbol
 703   (struct bfd_link_info *, struct elf_x86_link_hash_table *,
 704    struct elf_link_hash_entry *, Elf_Internal_Sym *sym);
 705
 706 #define bfd_elf64_mkobject \
 707   _bfd_x86_elf_mkobject
 708 #define bfd_elf32_mkobject \
 709   _bfd_x86_elf_mkobject
 710 #define bfd_elf64_bfd_link_hash_table_create \
 711   _bfd_x86_elf_link_hash_table_create
 712 #define bfd_elf32_bfd_link_hash_table_create \
 713   _bfd_x86_elf_link_hash_table_create
 714 #define bfd_elf64_bfd_link_check_relocs \
 715   _bfd_x86_elf_link_check_relocs
 716 #define bfd_elf32_bfd_link_check_relocs \
 717   _bfd_x86_elf_link_check_relocs
 718
 719 #define elf_backend_size_dynamic_sections \
 720   _bfd_x86_elf_size_dynamic_sections
 721 #define elf_backend_always_size_sections \
 722   _bfd_x86_elf_always_size_sections
 723 #define elf_backend_merge_symbol_attribute \
 724   _bfd_x86_elf_merge_symbol_attribute
 725 #define elf_backend_copy_indirect_symbol \
 726   _bfd_x86_elf_copy_indirect_symbol
 727 #define elf_backend_fixup_symbol \
 728   _bfd_x86_elf_fixup_symbol
 729 #define elf_backend_hash_symbol \
 730   _bfd_x86_elf_hash_symbol
 731 #define elf_backend_adjust_dynamic_symbol \
 732   _bfd_x86_elf_adjust_dynamic_symbol
 733 #define elf_backend_gc_mark_hook \
 734   _bfd_x86_elf_gc_mark_hook
 735 #define elf_backend_omit_section_dynsym \
 736   _bfd_elf_omit_section_dynsym_all
 737 #define elf_backend_parse_gnu_properties \
 738   _bfd_x86_elf_parse_gnu_properties
 739 #define elf_backend_merge_gnu_properties \
 740   _bfd_x86_elf_merge_gnu_properties
 741 #define elf_backend_fixup_gnu_properties \
 742   _bfd_x86_elf_link_fixup_gnu_properties