bfd/elfxx-x86.h

   1 /* x86 specific support for ELF
   2    Copyright (C) 2017-2018 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 /* TRUE if an undefined weak symbol should be resolved to 0.  Local
  53    undefined weak symbol is always resolved to 0.  Reference to an
  54    undefined weak symbol is resolved to 0 in executable if undefined
  55    weak symbol should be resolved to 0 (zero_undefweak > 0).  */
  56 #define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, EH) \
  57   ((EH)->elf.root.type == bfd_link_hash_undefweak                \
  58    && (SYMBOL_REFERENCES_LOCAL_P ((INFO), &(EH)->elf)            \
  59        || (bfd_link_executable (INFO)                            \
  60            && (EH)->zero_undefweak > 0)))
  61
  62 /* Should copy relocation be generated for a symbol.  Don't generate
  63    copy relocation against a protected symbol defined in a shared
  64    object with GNU_PROPERTY_NO_COPY_ON_PROTECTED.  */
  65 #define SYMBOL_NO_COPYRELOC(INFO, EH) \
  66   ((EH)->def_protected \
  67    && ((EH)->elf.root.type == bfd_link_hash_defined \
  68        || (EH)->elf.root.type == bfd_link_hash_defweak) \
  69    && elf_has_no_copy_on_protected ((EH)->elf.root.u.def.section->owner) \
  70    && ((EH)->elf.root.u.def.section->owner->flags & DYNAMIC) != 0 \
  71    && ((EH)->elf.root.u.def.section->flags & SEC_CODE) == 0)
  72
  73 /* TRUE if dynamic relocation is needed.  If we are creating a shared
  74    library, and this is a reloc against a global symbol, or a non PC
  75    relative reloc against a local symbol, then we need to copy the reloc
  76    into the shared library.  However, if we are linking with -Bsymbolic,
  77    we do not need to copy a reloc against a global symbol which is
  78    defined in an object we are including in the link (i.e., DEF_REGULAR
  79    is set).
  80
  81    If PCREL_PLT is true, don't generate dynamic relocation in PIE for
  82    PC-relative relocation against a dynamic function definition in data
  83    section when PLT address can be used.
  84
  85    If on the other hand, we are creating an executable, we may need to
  86    keep relocations for symbols satisfied by a dynamic library if we
  87    manage to avoid copy relocs for the symbol.
  88
  89    We also need to generate dynamic pointer relocation against
  90    STT_GNU_IFUNC symbol in the non-code section.  */
  91 #define NEED_DYNAMIC_RELOCATION_P(INFO, PCREL_PLT, H, SEC, R_TYPE, \
  92                                   POINTER_TYPE) \
  93   ((bfd_link_pic (INFO) \
  94     && (! X86_PCREL_TYPE_P (R_TYPE) \
  95         || ((H) != NULL \
  96             && (! (bfd_link_pie (INFO) \
  97                    || SYMBOLIC_BIND ((INFO), (H))) \
  98                 || (H)->root.type == bfd_link_hash_defweak \
  99                 || (!(bfd_link_pie (INFO) \
 100                       && (PCREL_PLT) \
 101                       && (H)->plt.refcount > 0 \
 102                       && ((SEC)->flags & SEC_CODE) == 0 \
 103                       && (H)->type == STT_FUNC \
 104                       && (H)->def_dynamic) \
 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)->elf.root.type == bfd_link_hash_undefweak \
 141                && !(RESOLVED_TO_ZERO))) \
 142                && (((EH)->elf.def_dynamic && !(EH)->elf.def_regular) \
 143                    || (EH)->elf.root.type == bfd_link_hash_undefined)))
 144
 145 /* TRUE if this input relocation should be copied to output.  H->dynindx
 146    may be -1 if this symbol was marked to become local.  */
 147 #define COPY_INPUT_RELOC_P(INFO, H, R_TYPE) \
 148   ((H) != NULL \
 149    && (H)->dynindx != -1 \
 150    && (X86_PCREL_TYPE_P (R_TYPE) \
 151        || !(bfd_link_executable (INFO) || SYMBOLIC_BIND ((INFO), (H))) \
 152        || !(H)->def_regular))
 153
 154 /* TRUE if this is actually a static link, or it is a -Bsymbolic link
 155    and the symbol is defined locally, or the symbol was forced to be
 156    local because of a version file.  */
 157 #define RESOLVED_LOCALLY_P(INFO, H, HTAB) \
 158   (!WILL_CALL_FINISH_DYNAMIC_SYMBOL ((HTAB)->elf.dynamic_sections_created, \
 159                                      bfd_link_pic (INFO), (H)) \
 160    || (bfd_link_pic (INFO) \
 161        && SYMBOL_REFERENCES_LOCAL_P ((INFO), (H))) \
 162        || (ELF_ST_VISIBILITY ((H)->other) \
 163            && (H)->root.type == bfd_link_hash_undefweak))
 164
 165 /* TRUE if relative relocation should be generated.  GOT reference to
 166    global symbol in PIC will lead to dynamic symbol.  It becomes a
 167    problem when "time" or "times" is defined as a variable in an
 168    executable, clashing with functions of the same name in libc.  If a
 169    symbol isn't undefined weak symbol, don't make it dynamic in PIC and
 170    generate relative relocation.  */
 171 #define GENERATE_RELATIVE_RELOC_P(INFO, H) \
 172   ((H)->dynindx == -1 \
 173    && !(H)->forced_local \
 174    && (H)->root.type != bfd_link_hash_undefweak \
 175    && bfd_link_pic (INFO))
 176
 177 /* TRUE if this is a pointer reference to a local IFUNC.  */
 178 #define POINTER_LOCAL_IFUNC_P(INFO, H) \
 179   ((H)->dynindx == -1 \
 180    || (H)->forced_local \
 181    || bfd_link_executable (INFO))
 182
 183 /* TRUE if this is a PLT reference to a local IFUNC.  */
 184 #define PLT_LOCAL_IFUNC_P(INFO, H) \
 185   ((H)->dynindx == -1 \
 186    || ((bfd_link_executable (INFO) \
 187         || ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT) \
 188         && (H)->def_regular \
 189         && (H)->type == STT_GNU_IFUNC))
 190
 191 /* TRUE if TLS IE->LE transition is OK.  */
 192 #define TLS_TRANSITION_IE_TO_LE_P(INFO, H, TLS_TYPE) \
 193   (bfd_link_executable (INFO) \
 194    && (H) != NULL \
 195    && (H)->dynindx == -1 \
 196    && (TLS_TYPE & GOT_TLS_IE))
 197
 198 /* Verify that the symbol has an entry in the procedure linkage table.  */
 199 #define VERIFY_PLT_ENTRY(INFO, H, PLT, GOTPLT, RELPLT, LOCAL_UNDEFWEAK) \
 200   do \
 201     { \
 202       if (((H)->dynindx == -1 \
 203            && !LOCAL_UNDEFWEAK \
 204            && !(((H)->forced_local || bfd_link_executable (INFO)) \
 205                 && (H)->def_regular \
 206                 && (H)->type == STT_GNU_IFUNC)) \
 207           || (PLT) == NULL \
 208           || (GOTPLT) == NULL \
 209           || (RELPLT) == NULL) \
 210         abort (); \
 211     } \
 212   while (0);
 213
 214 /* Verify that the symbol supports copy relocation.  */
 215 #define VERIFY_COPY_RELOC(H, HTAB) \
 216   do \
 217     { \
 218       if ((H)->dynindx == -1 \
 219           || ((H)->root.type != bfd_link_hash_defined \
 220               && (H)->root.type != bfd_link_hash_defweak) \
 221           || (HTAB)->elf.srelbss == NULL \
 222           || (HTAB)->elf.sreldynrelro == NULL) \
 223         abort (); \
 224     } \
 225   while (0);
 226
 227 /* x86 ELF linker hash entry.  */
 228
 229 struct elf_x86_link_hash_entry
 230 {
 231   struct elf_link_hash_entry elf;
 232
 233   /* Track dynamic relocs copied for this symbol.  */
 234   struct elf_dyn_relocs *dyn_relocs;
 235
 236   unsigned char tls_type;
 237
 238   /* Bit 0: Symbol has no GOT nor PLT relocations.
 239      Bit 1: Symbol has non-GOT/non-PLT relocations in text sections.
 240      zero_undefweak is initialized to 1 and undefined weak symbol
 241      should be resolved to 0 if zero_undefweak > 0.  */
 242   unsigned int zero_undefweak : 2;
 243
 244   /* Don't call finish_dynamic_symbol on this symbol.  */
 245   unsigned int no_finish_dynamic_symbol : 1;
 246
 247   /* TRUE if symbol is __tls_get_addr.  */
 248   unsigned int tls_get_addr : 1;
 249
 250   /* TRUE if symbol is defined as a protected symbol.  */
 251   unsigned int def_protected : 1;
 252
 253   /* 0: Symbol references are unknown.
 254      1: Symbol references aren't local.
 255      2: Symbol references are local.
 256    */
 257   unsigned int local_ref : 2;
 258
 259   /* TRUE if symbol is defined by linker.  */
 260   unsigned int linker_def : 1;
 261
 262   /* TRUE if symbol is referenced by R_386_GOTOFF relocation.  This is
 263      only used by i386.  */
 264   unsigned int gotoff_ref : 1;
 265
 266   /* TRUE if a weak symbol with a real definition needs a copy reloc.
 267      When there is a weak symbol with a real definition, the processor
 268      independent code will have arranged for us to see the real
 269      definition first.  We need to copy the needs_copy bit from the
 270      real definition and check it when allowing copy reloc in PIE.  This
 271      is only used by x86-64.  */
 272   unsigned int needs_copy : 1;
 273
 274   /* Information about the GOT PLT entry. Filled when there are both
 275      GOT and PLT relocations against the same function.  */
 276   union gotplt_union plt_got;
 277
 278   /* Information about the second PLT entry.   */
 279   union gotplt_union plt_second;
 280
 281   /* Offset of the GOTPLT entry reserved for the TLS descriptor,
 282      starting at the end of the jump table.  */
 283   bfd_vma tlsdesc_got;
 284 };
 285
 286 struct elf_x86_lazy_plt_layout
 287 {
 288   /* The first entry in a lazy procedure linkage table looks like this.  */
 289   const bfd_byte *plt0_entry;
 290   unsigned int plt0_entry_size;          /* Size of PLT0 entry.  */
 291
 292   /* Later entries in a lazy procedure linkage table look like this.  */
 293   const bfd_byte *plt_entry;
 294   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 295
 296   /* The TLSDESC entry in a lazy procedure linkage table looks like
 297      this.  This is for x86-64 only.  */
 298   const bfd_byte *plt_tlsdesc_entry;
 299   unsigned int plt_tlsdesc_entry_size;   /* Size of TLSDESC entry.  */
 300
 301   /* Offsets into the TLSDESC entry that are to be replaced with
 302      GOT+8 and GOT+TDG.  These are for x86-64 only.  */
 303   unsigned int plt_tlsdesc_got1_offset;
 304   unsigned int plt_tlsdesc_got2_offset;
 305
 306   /* Offset of the end of the PC-relative instructions containing
 307      plt_tlsdesc_got1_offset and plt_tlsdesc_got2_offset.  These
 308      are for x86-64 only.  */
 309   unsigned int plt_tlsdesc_got1_insn_end;
 310   unsigned int plt_tlsdesc_got2_insn_end;
 311
 312   /* Offsets into plt0_entry that are to be replaced with GOT[1] and
 313      GOT[2].  */
 314   unsigned int plt0_got1_offset;
 315   unsigned int plt0_got2_offset;
 316
 317   /* Offset of the end of the PC-relative instruction containing
 318      plt0_got2_offset.  This is for x86-64 only.  */
 319   unsigned int plt0_got2_insn_end;
 320
 321   /* Offsets into plt_entry that are to be replaced with...  */
 322   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 323   unsigned int plt_reloc_offset;  /* ... offset into relocation table. */
 324   unsigned int plt_plt_offset;    /* ... offset to start of .plt. */
 325
 326   /* Length of the PC-relative instruction containing plt_got_offset.
 327      This is used for x86-64 only.  */
 328   unsigned int plt_got_insn_size;
 329
 330   /* Offset of the end of the PC-relative jump to plt0_entry.  This is
 331      used for x86-64 only.  */
 332   unsigned int plt_plt_insn_end;
 333
 334   /* Offset into plt_entry where the initial value of the GOT entry
 335      points.  */
 336   unsigned int plt_lazy_offset;
 337
 338   /* The first entry in a PIC lazy procedure linkage table looks like
 339      this.  */
 340   const bfd_byte *pic_plt0_entry;
 341
 342   /* Subsequent entries in a PIC lazy procedure linkage table look
 343      like this.  */
 344   const bfd_byte *pic_plt_entry;
 345
 346   /* .eh_frame covering the lazy .plt section.  */
 347   const bfd_byte *eh_frame_plt;
 348   unsigned int eh_frame_plt_size;
 349 };
 350
 351 struct elf_x86_non_lazy_plt_layout
 352 {
 353   /* Entries in a non-lazy procedure linkage table look like this.  */
 354   const bfd_byte *plt_entry;
 355   /* Entries in a PIC non-lazy procedure linkage table look like this.
 356      This is only used for i386 where absolute PLT and PIC PLT are
 357      different.  */
 358   const bfd_byte *pic_plt_entry;
 359
 360   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 361
 362   /* Offsets into plt_entry that are to be replaced with...  */
 363   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 364
 365   /* Length of the PC-relative instruction containing plt_got_offset.
 366      This is used for x86-64 only.  */
 367   unsigned int plt_got_insn_size;
 368
 369   /* .eh_frame covering the non-lazy .plt section.  */
 370   const bfd_byte *eh_frame_plt;
 371   unsigned int eh_frame_plt_size;
 372 };
 373
 374 struct elf_x86_plt_layout
 375 {
 376   /* The first entry in a lazy procedure linkage table looks like this.  */
 377   const bfd_byte *plt0_entry;
 378   /* Entries in a procedure linkage table look like this.  */
 379   const bfd_byte *plt_entry;
 380   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 381
 382   /* 1 has PLT0.  */
 383   unsigned int has_plt0;
 384
 385   /* Offsets into plt_entry that are to be replaced with...  */
 386   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 387
 388   /* Length of the PC-relative instruction containing plt_got_offset.
 389      This is only used for x86-64.  */
 390   unsigned int plt_got_insn_size;
 391
 392   /* .eh_frame covering the .plt section.  */
 393   const bfd_byte *eh_frame_plt;
 394   unsigned int eh_frame_plt_size;
 395 };
 396
 397 /* Values in tls_type of x86 ELF linker hash entry.  */
 398 #define GOT_UNKNOWN     0
 399 #define GOT_NORMAL      1
 400 #define GOT_TLS_GD      2
 401 #define GOT_TLS_IE      4
 402 #define GOT_TLS_IE_POS  5
 403 #define GOT_TLS_IE_NEG  6
 404 #define GOT_TLS_IE_BOTH 7
 405 #define GOT_TLS_GDESC   8
 406 #define GOT_TLS_GD_BOTH_P(type) \
 407   ((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
 408 #define GOT_TLS_GD_P(type) \
 409   ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
 410 #define GOT_TLS_GDESC_P(type) \
 411   ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
 412 #define GOT_TLS_GD_ANY_P(type) \
 413   (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
 414
 415 #define elf_x86_hash_entry(ent) \
 416   ((struct elf_x86_link_hash_entry *)(ent))
 417
 418 enum elf_x86_target_os
 419 {
 420   is_normal,
 421   is_solaris,
 422   is_vxworks,
 423   is_nacl
 424 };
 425
 426 /* x86 ELF linker hash table.  */
 427
 428 struct elf_x86_link_hash_table
 429 {
 430   struct elf_link_hash_table elf;
 431
 432   /* Short-cuts to get to dynamic linker sections.  */
 433   asection *interp;
 434   asection *plt_eh_frame;
 435   asection *plt_second;
 436   asection *plt_second_eh_frame;
 437   asection *plt_got;
 438   asection *plt_got_eh_frame;
 439
 440   /* Parameters describing PLT generation, lazy or non-lazy.  */
 441   struct elf_x86_plt_layout plt;
 442
 443   /* Parameters describing lazy PLT generation.  */
 444   const struct elf_x86_lazy_plt_layout *lazy_plt;
 445
 446   /* Parameters describing non-lazy PLT generation.  */
 447   const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
 448
 449   union
 450   {
 451     bfd_signed_vma refcount;
 452     bfd_vma offset;
 453   } tls_ld_or_ldm_got;
 454
 455   /* The amount of space used by the jump slots in the GOT.  */
 456   bfd_vma sgotplt_jump_table_size;
 457
 458   /* Small local sym cache.  */
 459   struct sym_cache sym_cache;
 460
 461   /* _TLS_MODULE_BASE_ symbol.  */
 462   struct bfd_link_hash_entry *tls_module_base;
 463
 464   /* Used by local STT_GNU_IFUNC symbols.  */
 465   htab_t loc_hash_table;
 466   void * loc_hash_memory;
 467
 468   /* The offset into sgot of the GOT entry used by the PLT entry
 469      above.  */
 470   bfd_vma tlsdesc_got;
 471
 472   /* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt.  */
 473   bfd_vma next_jump_slot_index;
 474   /* The index of the next R_X86_64_IRELATIVE entry in .rela.plt.  */
 475   bfd_vma next_irelative_index;
 476
 477   /* TRUE if there are dynamic relocs against IFUNC symbols that apply
 478      to read-only sections.  */
 479   bfd_boolean readonly_dynrelocs_against_ifunc;
 480
 481   /* The (unloaded but important) .rel.plt.unloaded section on VxWorks.
 482      This is used for i386 only.  */
 483   asection *srelplt2;
 484
 485   /* The index of the next unused R_386_TLS_DESC slot in .rel.plt.  This
 486      is only used for i386.  */
 487   bfd_vma next_tls_desc_index;
 488
 489   /* The offset into splt of the PLT entry for the TLS descriptor
 490      resolver.  Special values are 0, if not necessary (or not found
 491      to be necessary yet), and -1 if needed but not determined
 492      yet.  This is only used for x86-64.  */
 493   bfd_vma tlsdesc_plt;
 494
 495    /* Value used to fill the unused bytes of the first PLT entry.  This
 496       is only used for i386.  */
 497   bfd_byte plt0_pad_byte;
 498
 499   /* TRUE if GOT is referenced.  */
 500   unsigned int got_referenced : 1;
 501
 502   /* TRUE if PLT is PC-relative.  PLT in PDE and PC-relative PLT in PIE
 503      can be used as function address.
 504
 505      NB: i386 has non-PIC PLT and PIC PLT.  Only non-PIC PLT in PDE can
 506      be used as function address.  PIC PLT in PIE can't be used as
 507      function address.  */
 508   unsigned int pcrel_plt : 1;
 509
 510   bfd_vma (*r_info) (bfd_vma, bfd_vma);
 511   bfd_vma (*r_sym) (bfd_vma);
 512   bfd_boolean (*is_reloc_section) (const char *);
 513   enum elf_target_id target_id;
 514   enum elf_x86_target_os target_os;
 515   unsigned int sizeof_reloc;
 516   unsigned int dt_reloc;
 517   unsigned int dt_reloc_sz;
 518   unsigned int dt_reloc_ent;
 519   unsigned int got_entry_size;
 520   unsigned int pointer_r_type;
 521   int dynamic_interpreter_size;
 522   const char *dynamic_interpreter;
 523   const char *tls_get_addr;
 524 };
 525
 526 /* Architecture-specific backend data for x86.  */
 527
 528 struct elf_x86_backend_data
 529 {
 530   /* Target system.  */
 531   enum elf_x86_target_os target_os;
 532 };
 533
 534 #define get_elf_x86_backend_data(abfd) \
 535   ((const struct elf_x86_backend_data *) \
 536    get_elf_backend_data (abfd)->arch_data)
 537
 538 struct elf_x86_init_table
 539 {
 540   /* The lazy PLT layout.  */
 541   const struct elf_x86_lazy_plt_layout *lazy_plt;
 542
 543   /* The non-lazy PLT layout.  */
 544   const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
 545
 546   /* The lazy PLT layout for IBT.  */
 547   const struct elf_x86_lazy_plt_layout *lazy_ibt_plt;
 548
 549   /* The non-lazy PLT layout for IBT.  */
 550   const struct elf_x86_non_lazy_plt_layout *non_lazy_ibt_plt;
 551
 552   bfd_byte plt0_pad_byte;
 553
 554   bfd_vma (*r_info) (bfd_vma, bfd_vma);
 555   bfd_vma (*r_sym) (bfd_vma);
 556 };
 557
 558 struct elf_x86_obj_tdata
 559 {
 560   struct elf_obj_tdata root;
 561
 562   /* tls_type for each local got entry.  */
 563   char *local_got_tls_type;
 564
 565   /* GOTPLT entries for TLS descriptors.  */
 566   bfd_vma *local_tlsdesc_gotent;
 567 };
 568
 569 enum elf_x86_plt_type
 570 {
 571   plt_non_lazy = 0,
 572   plt_lazy = 1 << 0,
 573   plt_pic = 1 << 1,
 574   plt_second = 1 << 2,
 575   plt_unknown = -1
 576 };
 577
 578 struct elf_x86_plt
 579 {
 580   const char *name;
 581   asection *sec;
 582   bfd_byte *contents;
 583   enum elf_x86_plt_type type;
 584   unsigned int plt_got_offset;
 585   unsigned int plt_entry_size;
 586   unsigned int plt_got_insn_size;       /* Only used for x86-64.  */
 587   long count;
 588 };
 589
 590 #define elf_x86_tdata(abfd) \
 591   ((struct elf_x86_obj_tdata *) (abfd)->tdata.any)
 592
 593 #define elf_x86_local_got_tls_type(abfd) \
 594   (elf_x86_tdata (abfd)->local_got_tls_type)
 595
 596 #define elf_x86_local_tlsdesc_gotent(abfd) \
 597   (elf_x86_tdata (abfd)->local_tlsdesc_gotent)
 598
 599 #define elf_x86_compute_jump_table_size(htab) \
 600   ((htab)->elf.srelplt->reloc_count * (htab)->got_entry_size)
 601
 602 #define is_x86_elf(bfd, htab)                           \
 603   (bfd_get_flavour (bfd) == bfd_target_elf_flavour      \
 604    && elf_tdata (bfd) != NULL                           \
 605    && elf_object_id (bfd) == (htab)->target_id)
 606
 607 extern bfd_boolean _bfd_x86_elf_mkobject
 608   (bfd *);
 609
 610 extern void _bfd_x86_elf_set_tls_module_base
 611   (struct bfd_link_info *);
 612
 613 extern bfd_vma _bfd_x86_elf_dtpoff_base
 614   (struct bfd_link_info *);
 615
 616 extern bfd_boolean _bfd_x86_elf_readonly_dynrelocs
 617   (struct elf_link_hash_entry *, void *);
 618
 619 extern struct elf_link_hash_entry * _bfd_elf_x86_get_local_sym_hash
 620   (struct elf_x86_link_hash_table *, bfd *, const Elf_Internal_Rela *,
 621    bfd_boolean);
 622
 623 extern hashval_t _bfd_x86_elf_local_htab_hash
 624   (const void *);
 625
 626 extern int _bfd_x86_elf_local_htab_eq
 627   (const void *, const void *);
 628
 629 extern struct bfd_hash_entry * _bfd_x86_elf_link_hash_newfunc
 630   (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
 631
 632 extern struct bfd_link_hash_table * _bfd_x86_elf_link_hash_table_create
 633   (bfd *);
 634
 635 extern int _bfd_x86_elf_compare_relocs
 636   (const void *, const void *);
 637
 638 extern bfd_boolean _bfd_x86_elf_link_check_relocs
 639   (bfd *, struct bfd_link_info *);
 640
 641 extern bfd_boolean _bfd_x86_elf_size_dynamic_sections
 642   (bfd *, struct bfd_link_info *);
 643
 644 extern struct elf_x86_link_hash_table *_bfd_x86_elf_finish_dynamic_sections
 645   (bfd *, struct bfd_link_info *);
 646
 647 extern bfd_boolean _bfd_x86_elf_always_size_sections
 648   (bfd *, struct bfd_link_info *);
 649
 650 extern void _bfd_x86_elf_merge_symbol_attribute
 651   (struct elf_link_hash_entry *, const Elf_Internal_Sym *,
 652    bfd_boolean, bfd_boolean);
 653
 654 extern void _bfd_x86_elf_copy_indirect_symbol
 655   (struct bfd_link_info *, struct elf_link_hash_entry *,
 656    struct elf_link_hash_entry *);
 657
 658 extern bfd_boolean _bfd_x86_elf_fixup_symbol
 659   (struct bfd_link_info *, struct elf_link_hash_entry *);
 660
 661 extern bfd_boolean _bfd_x86_elf_hash_symbol
 662   (struct elf_link_hash_entry *);
 663
 664 extern bfd_boolean _bfd_x86_elf_adjust_dynamic_symbol
 665   (struct bfd_link_info *, struct elf_link_hash_entry *);
 666
 667 extern void _bfd_x86_elf_hide_symbol
 668   (struct bfd_link_info *, struct elf_link_hash_entry *, bfd_boolean);
 669
 670 extern bfd_boolean _bfd_x86_elf_link_symbol_references_local
 671   (struct bfd_link_info *, struct elf_link_hash_entry *);
 672
 673 extern asection * _bfd_x86_elf_gc_mark_hook
 674   (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
 675    struct elf_link_hash_entry *, Elf_Internal_Sym *);
 676
 677 extern long _bfd_x86_elf_get_synthetic_symtab
 678   (bfd *, long, long, bfd_vma, struct elf_x86_plt [], asymbol **,
 679    asymbol **);
 680
 681 extern enum elf_property_kind _bfd_x86_elf_parse_gnu_properties
 682   (bfd *, unsigned int, bfd_byte *, unsigned int);
 683
 684 extern bfd_boolean _bfd_x86_elf_merge_gnu_properties
 685   (struct bfd_link_info *, bfd *, elf_property *, elf_property *);
 686
 687 extern void _bfd_x86_elf_link_fixup_gnu_properties
 688   (struct bfd_link_info *, elf_property_list **);
 689
 690 extern bfd * _bfd_x86_elf_link_setup_gnu_properties
 691   (struct bfd_link_info *, struct elf_x86_init_table *);
 692
 693 extern void _bfd_x86_elf_link_fixup_ifunc_symbol
 694   (struct bfd_link_info *, struct elf_x86_link_hash_table *,
 695    struct elf_link_hash_entry *, Elf_Internal_Sym *sym);
 696
 697 #define bfd_elf64_mkobject \
 698   _bfd_x86_elf_mkobject
 699 #define bfd_elf32_mkobject \
 700   _bfd_x86_elf_mkobject
 701 #define bfd_elf64_bfd_link_hash_table_create \
 702   _bfd_x86_elf_link_hash_table_create
 703 #define bfd_elf32_bfd_link_hash_table_create \
 704   _bfd_x86_elf_link_hash_table_create
 705 #define bfd_elf64_bfd_link_check_relocs \
 706   _bfd_x86_elf_link_check_relocs
 707 #define bfd_elf32_bfd_link_check_relocs \
 708   _bfd_x86_elf_link_check_relocs
 709
 710 #define elf_backend_size_dynamic_sections \
 711   _bfd_x86_elf_size_dynamic_sections
 712 #define elf_backend_always_size_sections \
 713   _bfd_x86_elf_always_size_sections
 714 #define elf_backend_merge_symbol_attribute \
 715   _bfd_x86_elf_merge_symbol_attribute
 716 #define elf_backend_copy_indirect_symbol \
 717   _bfd_x86_elf_copy_indirect_symbol
 718 #define elf_backend_fixup_symbol \
 719   _bfd_x86_elf_fixup_symbol
 720 #define elf_backend_hash_symbol \
 721   _bfd_x86_elf_hash_symbol
 722 #define elf_backend_adjust_dynamic_symbol \
 723   _bfd_x86_elf_adjust_dynamic_symbol
 724 #define elf_backend_gc_mark_hook \
 725   _bfd_x86_elf_gc_mark_hook
 726 #define elf_backend_omit_section_dynsym \
 727   _bfd_elf_omit_section_dynsym_all
 728 #define elf_backend_parse_gnu_properties \
 729   _bfd_x86_elf_parse_gnu_properties
 730 #define elf_backend_merge_gnu_properties \
 731   _bfd_x86_elf_merge_gnu_properties
 732 #define elf_backend_fixup_gnu_properties \
 733   _bfd_x86_elf_link_fixup_gnu_properties