bfd/elfxx-x86.h

   1 /* x86 specific support for ELF
   2    Copyright (C) 2017-2020 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 #include "elf-linker-x86.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.  Don't generate dynamic relocations against
 123    non-preemptible absolute symbol.  */
 124 #define GENERATE_DYNAMIC_RELOCATION_P(INFO, EH, R_TYPE, SEC, \
 125                                       NEED_COPY_RELOC_IN_PIE, \
 126                                       RESOLVED_TO_ZERO, PC32_RELOC) \
 127   ((bfd_link_pic (INFO) \
 128     && !(bfd_is_abs_section (SEC) \
 129          && ((EH) == NULL \
 130              || SYMBOL_REFERENCES_LOCAL (INFO, &(EH)->elf))) \
 131     && !(NEED_COPY_RELOC_IN_PIE) \
 132     && ((EH) == NULL \
 133         || ((ELF_ST_VISIBILITY ((EH)->elf.other) == STV_DEFAULT \
 134              && (!(RESOLVED_TO_ZERO) || PC32_RELOC)) \
 135             || (EH)->elf.root.type != bfd_link_hash_undefweak)) \
 136     && ((!X86_PCREL_TYPE_P (R_TYPE) && !X86_SIZE_TYPE_P (R_TYPE)) \
 137         || ! SYMBOL_CALLS_LOCAL ((INFO), \
 138                                  (struct elf_link_hash_entry *) (EH)))) \
 139    || (ELIMINATE_COPY_RELOCS \
 140        && !bfd_link_pic (INFO) \
 141        && (EH) != NULL \
 142        && (EH)->elf.dynindx != -1 \
 143        && (!(EH)->elf.non_got_ref \
 144            || ((EH)->elf.root.type == bfd_link_hash_undefweak \
 145                && !(RESOLVED_TO_ZERO))) \
 146                && (((EH)->elf.def_dynamic && !(EH)->elf.def_regular) \
 147                    || (EH)->elf.root.type == bfd_link_hash_undefined)))
 148
 149 /* TRUE if this input relocation should be copied to output.  H->dynindx
 150    may be -1 if this symbol was marked to become local.  */
 151 #define COPY_INPUT_RELOC_P(INFO, H, R_TYPE) \
 152   ((H) != NULL \
 153    && (H)->dynindx != -1 \
 154    && (X86_PCREL_TYPE_P (R_TYPE) \
 155        || !(bfd_link_executable (INFO) || SYMBOLIC_BIND ((INFO), (H))) \
 156        || !(H)->def_regular))
 157
 158 /* TRUE if this is actually a static link, or it is a -Bsymbolic link
 159    and the symbol is defined locally, or the symbol was forced to be
 160    local because of a version file.  */
 161 #define RESOLVED_LOCALLY_P(INFO, H, HTAB) \
 162   (!WILL_CALL_FINISH_DYNAMIC_SYMBOL ((HTAB)->elf.dynamic_sections_created, \
 163                                      bfd_link_pic (INFO), (H)) \
 164    || (bfd_link_pic (INFO) \
 165        && SYMBOL_REFERENCES_LOCAL_P ((INFO), (H))) \
 166        || (ELF_ST_VISIBILITY ((H)->other) \
 167            && (H)->root.type == bfd_link_hash_undefweak))
 168
 169 /* TRUE if this symbol isn't defined by a shared object.  */
 170 #define SYMBOL_DEFINED_NON_SHARED_P(H) \
 171   ((H)->def_regular \
 172    || (H)->root.linker_def \
 173    || (H)->root.ldscript_def \
 174    || ((struct elf_x86_link_hash_entry *) (H))->linker_def \
 175    || ELF_COMMON_DEF_P (H))
 176
 177 /* Return TRUE if the symbol described by a linker hash entry H is
 178    going to be absolute.  Similar to bfd_is_abs_symbol, but excluding
 179    all linker-script defined symbols.  */
 180 #define ABS_SYMBOL_P(H) \
 181   (bfd_is_abs_symbol (&(H)->root) && !(H)->root.ldscript_def)
 182
 183 /* TRUE if relative relocation should be generated.  GOT reference to
 184    global symbol in PIC will lead to dynamic symbol.  It becomes a
 185    problem when "time" or "times" is defined as a variable in an
 186    executable, clashing with functions of the same name in libc.  If a
 187    symbol isn't undefined weak symbol, don't make it dynamic in PIC and
 188    generate relative relocation.   Don't generate relative relocation
 189    against non-preemptible absolute symbol.  */
 190 #define GENERATE_RELATIVE_RELOC_P(INFO, H) \
 191   ((H)->dynindx == -1 \
 192    && !(H)->forced_local \
 193    && (H)->root.type != bfd_link_hash_undefweak \
 194    && bfd_link_pic (INFO) \
 195    && !ABS_SYMBOL_P (H))
 196
 197 /* TRUE if this is a pointer reference to a local IFUNC.  */
 198 #define POINTER_LOCAL_IFUNC_P(INFO, H) \
 199   ((H)->dynindx == -1 \
 200    || (H)->forced_local \
 201    || bfd_link_executable (INFO))
 202
 203 /* TRUE if this is a PLT reference to a local IFUNC.  */
 204 #define PLT_LOCAL_IFUNC_P(INFO, H) \
 205   ((H)->dynindx == -1 \
 206    || ((bfd_link_executable (INFO) \
 207         || ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT) \
 208         && (H)->def_regular \
 209         && (H)->type == STT_GNU_IFUNC))
 210
 211 /* TRUE if TLS IE->LE transition is OK.  */
 212 #define TLS_TRANSITION_IE_TO_LE_P(INFO, H, TLS_TYPE) \
 213   (bfd_link_executable (INFO) \
 214    && (H) != NULL \
 215    && (H)->dynindx == -1 \
 216    && (TLS_TYPE & GOT_TLS_IE))
 217
 218 /* Verify that the symbol has an entry in the procedure linkage table.  */
 219 #define VERIFY_PLT_ENTRY(INFO, H, PLT, GOTPLT, RELPLT, LOCAL_UNDEFWEAK) \
 220   do \
 221     { \
 222       if (((H)->dynindx == -1 \
 223            && !LOCAL_UNDEFWEAK \
 224            && !(((H)->forced_local || bfd_link_executable (INFO)) \
 225                 && (H)->def_regular \
 226                 && (H)->type == STT_GNU_IFUNC)) \
 227           || (PLT) == NULL \
 228           || (GOTPLT) == NULL \
 229           || (RELPLT) == NULL) \
 230         abort (); \
 231     } \
 232   while (0);
 233
 234 /* Verify that the symbol supports copy relocation.  */
 235 #define VERIFY_COPY_RELOC(H, HTAB) \
 236   do \
 237     { \
 238       if ((H)->dynindx == -1 \
 239           || ((H)->root.type != bfd_link_hash_defined \
 240               && (H)->root.type != bfd_link_hash_defweak) \
 241           || (HTAB)->elf.srelbss == NULL \
 242           || (HTAB)->elf.sreldynrelro == NULL) \
 243         abort (); \
 244     } \
 245   while (0);
 246
 247 /* x86 ELF linker hash entry.  */
 248
 249 struct elf_x86_link_hash_entry
 250 {
 251   struct elf_link_hash_entry elf;
 252
 253   unsigned char tls_type;
 254
 255   /* Bit 0: Symbol has no GOT nor PLT relocations.
 256      Bit 1: Symbol has non-GOT/non-PLT relocations in text sections.
 257      zero_undefweak is initialized to 1 and undefined weak symbol
 258      should be resolved to 0 if zero_undefweak > 0.  */
 259   unsigned int zero_undefweak : 2;
 260
 261   /* Don't call finish_dynamic_symbol on this symbol.  */
 262   unsigned int no_finish_dynamic_symbol : 1;
 263
 264   /* TRUE if symbol is __tls_get_addr.  */
 265   unsigned int tls_get_addr : 1;
 266
 267   /* TRUE if symbol is defined as a protected symbol.  */
 268   unsigned int def_protected : 1;
 269
 270   /* 0: Symbol references are unknown.
 271      1: Symbol references aren't local.
 272      2: Symbol references are local.
 273    */
 274   unsigned int local_ref : 2;
 275
 276   /* TRUE if symbol is defined by linker.  */
 277   unsigned int linker_def : 1;
 278
 279   /* TRUE if symbol is referenced by R_386_GOTOFF relocation.  This is
 280      only used by i386.  */
 281   unsigned int gotoff_ref : 1;
 282
 283   /* TRUE if a weak symbol with a real definition needs a copy reloc.
 284      When there is a weak symbol with a real definition, the processor
 285      independent code will have arranged for us to see the real
 286      definition first.  We need to copy the needs_copy bit from the
 287      real definition and check it when allowing copy reloc in PIE.  This
 288      is only used by x86-64.  */
 289   unsigned int needs_copy : 1;
 290
 291   /* Information about the GOT PLT entry. Filled when there are both
 292      GOT and PLT relocations against the same function.  */
 293   union gotplt_union plt_got;
 294
 295   /* Information about the second PLT entry.   */
 296   union gotplt_union plt_second;
 297
 298   /* Offset of the GOTPLT entry reserved for the TLS descriptor,
 299      starting at the end of the jump table.  */
 300   bfd_vma tlsdesc_got;
 301 };
 302
 303 struct elf_x86_lazy_plt_layout
 304 {
 305   /* The first entry in a lazy procedure linkage table looks like this.  */
 306   const bfd_byte *plt0_entry;
 307   unsigned int plt0_entry_size;          /* Size of PLT0 entry.  */
 308
 309   /* Later entries in a lazy procedure linkage table look like this.  */
 310   const bfd_byte *plt_entry;
 311   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 312
 313   /* The TLSDESC entry in a lazy procedure linkage table looks like
 314      this.  This is for x86-64 only.  */
 315   const bfd_byte *plt_tlsdesc_entry;
 316   unsigned int plt_tlsdesc_entry_size;   /* Size of TLSDESC entry.  */
 317
 318   /* Offsets into the TLSDESC entry that are to be replaced with
 319      GOT+8 and GOT+TDG.  These are for x86-64 only.  */
 320   unsigned int plt_tlsdesc_got1_offset;
 321   unsigned int plt_tlsdesc_got2_offset;
 322
 323   /* Offset of the end of the PC-relative instructions containing
 324      plt_tlsdesc_got1_offset and plt_tlsdesc_got2_offset.  These
 325      are for x86-64 only.  */
 326   unsigned int plt_tlsdesc_got1_insn_end;
 327   unsigned int plt_tlsdesc_got2_insn_end;
 328
 329   /* Offsets into plt0_entry that are to be replaced with GOT[1] and
 330      GOT[2].  */
 331   unsigned int plt0_got1_offset;
 332   unsigned int plt0_got2_offset;
 333
 334   /* Offset of the end of the PC-relative instruction containing
 335      plt0_got2_offset.  This is for x86-64 only.  */
 336   unsigned int plt0_got2_insn_end;
 337
 338   /* Offsets into plt_entry that are to be replaced with...  */
 339   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 340   unsigned int plt_reloc_offset;  /* ... offset into relocation table. */
 341   unsigned int plt_plt_offset;    /* ... offset to start of .plt. */
 342
 343   /* Length of the PC-relative instruction containing plt_got_offset.
 344      This is used for x86-64 only.  */
 345   unsigned int plt_got_insn_size;
 346
 347   /* Offset of the end of the PC-relative jump to plt0_entry.  This is
 348      used for x86-64 only.  */
 349   unsigned int plt_plt_insn_end;
 350
 351   /* Offset into plt_entry where the initial value of the GOT entry
 352      points.  */
 353   unsigned int plt_lazy_offset;
 354
 355   /* The first entry in a PIC lazy procedure linkage table looks like
 356      this.  */
 357   const bfd_byte *pic_plt0_entry;
 358
 359   /* Subsequent entries in a PIC lazy procedure linkage table look
 360      like this.  */
 361   const bfd_byte *pic_plt_entry;
 362
 363   /* .eh_frame covering the lazy .plt section.  */
 364   const bfd_byte *eh_frame_plt;
 365   unsigned int eh_frame_plt_size;
 366 };
 367
 368 struct elf_x86_non_lazy_plt_layout
 369 {
 370   /* Entries in a non-lazy procedure linkage table look like this.  */
 371   const bfd_byte *plt_entry;
 372   /* Entries in a PIC non-lazy procedure linkage table look like this.
 373      This is only used for i386 where absolute PLT and PIC PLT are
 374      different.  */
 375   const bfd_byte *pic_plt_entry;
 376
 377   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 378
 379   /* Offsets into plt_entry that are to be replaced with...  */
 380   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 381
 382   /* Length of the PC-relative instruction containing plt_got_offset.
 383      This is used for x86-64 only.  */
 384   unsigned int plt_got_insn_size;
 385
 386   /* .eh_frame covering the non-lazy .plt section.  */
 387   const bfd_byte *eh_frame_plt;
 388   unsigned int eh_frame_plt_size;
 389 };
 390
 391 struct elf_x86_plt_layout
 392 {
 393   /* The first entry in a lazy procedure linkage table looks like this.  */
 394   const bfd_byte *plt0_entry;
 395   /* Entries in a procedure linkage table look like this.  */
 396   const bfd_byte *plt_entry;
 397   unsigned int plt_entry_size;          /* Size of each PLT entry.  */
 398
 399   /* 1 has PLT0.  */
 400   unsigned int has_plt0;
 401
 402   /* Offsets into plt_entry that are to be replaced with...  */
 403   unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
 404
 405   /* Length of the PC-relative instruction containing plt_got_offset.
 406      This is only used for x86-64.  */
 407   unsigned int plt_got_insn_size;
 408
 409   /* Alignment of the .iplt section.  */
 410   unsigned int iplt_alignment;
 411
 412   /* .eh_frame covering the .plt section.  */
 413   const bfd_byte *eh_frame_plt;
 414   unsigned int eh_frame_plt_size;
 415 };
 416
 417 /* Values in tls_type of x86 ELF linker hash entry.  */
 418 #define GOT_UNKNOWN     0
 419 #define GOT_NORMAL      1
 420 #define GOT_TLS_GD      2
 421 #define GOT_TLS_IE      4
 422 #define GOT_TLS_IE_POS  5
 423 #define GOT_TLS_IE_NEG  6
 424 #define GOT_TLS_IE_BOTH 7
 425 #define GOT_TLS_GDESC   8
 426 #define GOT_ABS         9
 427 #define GOT_TLS_GD_BOTH_P(type) \
 428   ((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
 429 #define GOT_TLS_GD_P(type) \
 430   ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
 431 #define GOT_TLS_GDESC_P(type) \
 432   ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
 433 #define GOT_TLS_GD_ANY_P(type) \
 434   (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
 435
 436 #define elf_x86_hash_entry(ent) \
 437   ((struct elf_x86_link_hash_entry *)(ent))
 438
 439 /* x86 ELF linker hash table.  */
 440
 441 struct elf_x86_link_hash_table
 442 {
 443   struct elf_link_hash_table elf;
 444
 445   /* Short-cuts to get to dynamic linker sections.  */
 446   asection *interp;
 447   asection *plt_eh_frame;
 448   asection *plt_second;
 449   asection *plt_second_eh_frame;
 450   asection *plt_got;
 451   asection *plt_got_eh_frame;
 452
 453   /* Parameters describing PLT generation, lazy or non-lazy.  */
 454   struct elf_x86_plt_layout plt;
 455
 456   /* Parameters describing lazy PLT generation.  */
 457   const struct elf_x86_lazy_plt_layout *lazy_plt;
 458
 459   /* Parameters describing non-lazy PLT generation.  */
 460   const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
 461
 462   union
 463   {
 464     bfd_signed_vma refcount;
 465     bfd_vma offset;
 466   } tls_ld_or_ldm_got;
 467
 468   /* The amount of space used by the jump slots in the GOT.  */
 469   bfd_vma sgotplt_jump_table_size;
 470
 471   /* Small local sym cache.  */
 472   struct sym_cache sym_cache;
 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 offset into sgot of the GOT entry used by the PLT entry
 482      above.  */
 483   bfd_vma tlsdesc_got;
 484
 485   /* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt.  */
 486   bfd_vma next_jump_slot_index;
 487   /* The index of the next R_X86_64_IRELATIVE entry in .rela.plt.  */
 488   bfd_vma next_irelative_index;
 489
 490   /* TRUE if there are dynamic relocs against IFUNC symbols that apply
 491      to read-only sections.  */
 492   bfd_boolean readonly_dynrelocs_against_ifunc;
 493
 494   /* The (unloaded but important) .rel.plt.unloaded section on VxWorks.
 495      This is used for i386 only.  */
 496   asection *srelplt2;
 497
 498   /* The index of the next unused R_386_TLS_DESC slot in .rel.plt.  This
 499      is only used for i386.  */
 500   bfd_vma next_tls_desc_index;
 501
 502   /* The offset into splt of the PLT entry for the TLS descriptor
 503      resolver.  Special values are 0, if not necessary (or not found
 504      to be necessary yet), and -1 if needed but not determined
 505      yet.  This is only used for x86-64.  */
 506   bfd_vma tlsdesc_plt;
 507
 508    /* Value used to fill the unused bytes of the first PLT entry.  This
 509       is only used for i386.  */
 510   bfd_byte plt0_pad_byte;
 511
 512   /* TRUE if GOT is referenced.  */
 513   unsigned int got_referenced : 1;
 514
 515   /* TRUE if PLT is PC-relative.  PLT in PDE and PC-relative PLT in PIE
 516      can be used as function address.
 517
 518      NB: i386 has non-PIC PLT and PIC PLT.  Only non-PIC PLT in PDE can
 519      be used as function address.  PIC PLT in PIE can't be used as
 520      function address.  */
 521   unsigned int pcrel_plt : 1;
 522
 523   bfd_vma (*r_info) (bfd_vma, bfd_vma);
 524   bfd_vma (*r_sym) (bfd_vma);
 525   bfd_boolean (*is_reloc_section) (const char *);
 526   unsigned int sizeof_reloc;
 527   unsigned int dt_reloc;
 528   unsigned int dt_reloc_sz;
 529   unsigned int dt_reloc_ent;
 530   unsigned int got_entry_size;
 531   unsigned int pointer_r_type;
 532   int dynamic_interpreter_size;
 533   const char *dynamic_interpreter;
 534   const char *tls_get_addr;
 535
 536   /* Options passed from the linker.  */
 537   struct elf_linker_x86_params *params;
 538 };
 539
 540 struct elf_x86_init_table
 541 {
 542   /* The lazy PLT layout.  */
 543   const struct elf_x86_lazy_plt_layout *lazy_plt;
 544
 545   /* The non-lazy PLT layout.  */
 546   const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
 547
 548   /* The lazy PLT layout for IBT.  */
 549   const struct elf_x86_lazy_plt_layout *lazy_ibt_plt;
 550
 551   /* The non-lazy PLT layout for IBT.  */
 552   const struct elf_x86_non_lazy_plt_layout *non_lazy_ibt_plt;
 553
 554   bfd_byte plt0_pad_byte;
 555
 556   bfd_vma (*r_info) (bfd_vma, bfd_vma);
 557   bfd_vma (*r_sym) (bfd_vma);
 558 };
 559
 560 struct elf_x86_obj_tdata
 561 {
 562   struct elf_obj_tdata root;
 563
 564   /* tls_type for each local got entry.  */
 565   char *local_got_tls_type;
 566
 567   /* GOTPLT entries for TLS descriptors.  */
 568   bfd_vma *local_tlsdesc_gotent;
 569 };
 570
 571 enum elf_x86_plt_type
 572 {
 573   plt_non_lazy = 0,
 574   plt_lazy = 1 << 0,
 575   plt_pic = 1 << 1,
 576   plt_second = 1 << 2,
 577   plt_unknown = -1
 578 };
 579
 580 struct elf_x86_plt
 581 {
 582   const char *name;
 583   asection *sec;
 584   bfd_byte *contents;
 585   enum elf_x86_plt_type type;
 586   unsigned int plt_got_offset;
 587   unsigned int plt_entry_size;
 588   unsigned int plt_got_insn_size;       /* Only used for x86-64.  */
 589   long count;
 590 };
 591
 592 /* Set if a relocation is converted from a GOTPCREL relocation.  */
 593 #define R_X86_64_converted_reloc_bit (1 << 7)
 594
 595 #define elf_x86_tdata(abfd) \
 596   ((struct elf_x86_obj_tdata *) (abfd)->tdata.any)
 597
 598 #define elf_x86_local_got_tls_type(abfd) \
 599   (elf_x86_tdata (abfd)->local_got_tls_type)
 600
 601 #define elf_x86_local_tlsdesc_gotent(abfd) \
 602   (elf_x86_tdata (abfd)->local_tlsdesc_gotent)
 603
 604 #define elf_x86_compute_jump_table_size(htab) \
 605   ((htab)->elf.srelplt->reloc_count * (htab)->got_entry_size)
 606
 607 #define is_x86_elf(bfd, htab)                           \
 608   (bfd_get_flavour (bfd) == bfd_target_elf_flavour      \
 609    && elf_tdata (bfd) != NULL                           \
 610    && elf_object_id (bfd) == (htab)->elf.hash_table_id)
 611
 612 extern bfd_boolean _bfd_x86_elf_mkobject
 613   (bfd *);
 614
 615 extern void _bfd_x86_elf_set_tls_module_base
 616   (struct bfd_link_info *);
 617
 618 extern bfd_vma _bfd_x86_elf_dtpoff_base
 619   (struct bfd_link_info *);
 620
 621 extern bfd_boolean _bfd_x86_elf_readonly_dynrelocs
 622   (struct elf_link_hash_entry *, void *);
 623
 624 extern struct elf_link_hash_entry * _bfd_elf_x86_get_local_sym_hash
 625   (struct elf_x86_link_hash_table *, bfd *, const Elf_Internal_Rela *,
 626    bfd_boolean);
 627
 628 extern hashval_t _bfd_x86_elf_local_htab_hash
 629   (const void *);
 630
 631 extern int _bfd_x86_elf_local_htab_eq
 632   (const void *, const void *);
 633
 634 extern struct bfd_hash_entry * _bfd_x86_elf_link_hash_newfunc
 635   (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
 636
 637 extern struct bfd_link_hash_table * _bfd_x86_elf_link_hash_table_create
 638   (bfd *);
 639
 640 extern int _bfd_x86_elf_compare_relocs
 641   (const void *, const void *);
 642
 643 extern bfd_boolean _bfd_x86_elf_link_check_relocs
 644   (bfd *, struct bfd_link_info *);
 645
 646 extern bfd_boolean _bfd_elf_x86_valid_reloc_p
 647   (asection *, struct bfd_link_info *, struct elf_x86_link_hash_table *,
 648    const Elf_Internal_Rela *, struct elf_link_hash_entry *,
 649    Elf_Internal_Sym *, Elf_Internal_Shdr *, bfd_boolean *);
 650
 651 extern bfd_boolean _bfd_x86_elf_size_dynamic_sections
 652   (bfd *, struct bfd_link_info *);
 653
 654 extern struct elf_x86_link_hash_table *_bfd_x86_elf_finish_dynamic_sections
 655   (bfd *, struct bfd_link_info *);
 656
 657 extern bfd_boolean _bfd_x86_elf_always_size_sections
 658   (bfd *, struct bfd_link_info *);
 659
 660 extern void _bfd_x86_elf_merge_symbol_attribute
 661   (struct elf_link_hash_entry *, const Elf_Internal_Sym *,
 662    bfd_boolean, bfd_boolean);
 663
 664 extern void _bfd_x86_elf_copy_indirect_symbol
 665   (struct bfd_link_info *, struct elf_link_hash_entry *,
 666    struct elf_link_hash_entry *);
 667
 668 extern bfd_boolean _bfd_x86_elf_fixup_symbol
 669   (struct bfd_link_info *, struct elf_link_hash_entry *);
 670
 671 extern bfd_boolean _bfd_x86_elf_hash_symbol
 672   (struct elf_link_hash_entry *);
 673
 674 extern bfd_boolean _bfd_x86_elf_adjust_dynamic_symbol
 675   (struct bfd_link_info *, struct elf_link_hash_entry *);
 676
 677 extern void _bfd_x86_elf_hide_symbol
 678   (struct bfd_link_info *, struct elf_link_hash_entry *, bfd_boolean);
 679
 680 extern bfd_boolean _bfd_x86_elf_link_symbol_references_local
 681   (struct bfd_link_info *, struct elf_link_hash_entry *);
 682
 683 extern asection * _bfd_x86_elf_gc_mark_hook
 684   (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
 685    struct elf_link_hash_entry *, Elf_Internal_Sym *);
 686
 687 extern long _bfd_x86_elf_get_synthetic_symtab
 688   (bfd *, long, long, bfd_vma, struct elf_x86_plt [], asymbol **,
 689    asymbol **);
 690
 691 extern enum elf_property_kind _bfd_x86_elf_parse_gnu_properties
 692   (bfd *, unsigned int, bfd_byte *, unsigned int);
 693
 694 extern bfd_boolean _bfd_x86_elf_merge_gnu_properties
 695   (struct bfd_link_info *, bfd *, bfd *, elf_property *, elf_property *);
 696
 697 extern void _bfd_x86_elf_link_fixup_gnu_properties
 698   (struct bfd_link_info *, elf_property_list **);
 699
 700 extern bfd * _bfd_x86_elf_link_setup_gnu_properties
 701   (struct bfd_link_info *, struct elf_x86_init_table *);
 702
 703 extern void _bfd_x86_elf_link_fixup_ifunc_symbol
 704   (struct bfd_link_info *, struct elf_x86_link_hash_table *,
 705    struct elf_link_hash_entry *, Elf_Internal_Sym *sym);
 706
 707 #define bfd_elf64_mkobject \
 708   _bfd_x86_elf_mkobject
 709 #define bfd_elf32_mkobject \
 710   _bfd_x86_elf_mkobject
 711 #define bfd_elf64_bfd_link_hash_table_create \
 712   _bfd_x86_elf_link_hash_table_create
 713 #define bfd_elf32_bfd_link_hash_table_create \
 714   _bfd_x86_elf_link_hash_table_create
 715 #define bfd_elf64_bfd_link_check_relocs \
 716   _bfd_x86_elf_link_check_relocs
 717 #define bfd_elf32_bfd_link_check_relocs \
 718   _bfd_x86_elf_link_check_relocs
 719
 720 #define elf_backend_size_dynamic_sections \
 721   _bfd_x86_elf_size_dynamic_sections
 722 #define elf_backend_always_size_sections \
 723   _bfd_x86_elf_always_size_sections
 724 #define elf_backend_merge_symbol_attribute \
 725   _bfd_x86_elf_merge_symbol_attribute
 726 #define elf_backend_copy_indirect_symbol \
 727   _bfd_x86_elf_copy_indirect_symbol
 728 #define elf_backend_fixup_symbol \
 729   _bfd_x86_elf_fixup_symbol
 730 #define elf_backend_hash_symbol \
 731   _bfd_x86_elf_hash_symbol
 732 #define elf_backend_adjust_dynamic_symbol \
 733   _bfd_x86_elf_adjust_dynamic_symbol
 734 #define elf_backend_gc_mark_hook \
 735   _bfd_x86_elf_gc_mark_hook
 736 #define elf_backend_omit_section_dynsym \
 737   _bfd_elf_omit_section_dynsym_all
 738 #define elf_backend_parse_gnu_properties \
 739   _bfd_x86_elf_parse_gnu_properties
 740 #define elf_backend_merge_gnu_properties \
 741   _bfd_x86_elf_merge_gnu_properties
 742 #define elf_backend_fixup_gnu_properties \
 743   _bfd_x86_elf_link_fixup_gnu_properties