Coverage Report

Created: 2024-05-21 06:29

/src/binutils-gdb/bfd/elfxx-x86.h
Line
Count
Source (jump to first uncovered line)
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/* x86 specific support for ELF
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   Copyright (C) 2017-2024 Free Software Foundation, Inc.
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4
   This file is part of BFD, the Binary File Descriptor library.
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6
   This program is free software; you can redistribute it and/or modify
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   it under the terms of the GNU General Public License as published by
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   the Free Software Foundation; either version 3 of the License, or
9
   (at your option) any later version.
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11
   This program is distributed in the hope that it will be useful,
12
   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14
   GNU General Public License for more details.
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   You should have received a copy of the GNU General Public License
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   along with this program; if not, write to the Free Software
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   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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   MA 02110-1301, USA.  */
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21
/* Don't generate unused section symbols.  */
22
#define TARGET_KEEP_UNUSED_SECTION_SYMBOLS false
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24
#include "sysdep.h"
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#include "bfd.h"
26
#include "bfdlink.h"
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#include "libbfd.h"
28
#include "elf-bfd.h"
29
#include "hashtab.h"
30
#include "elf-linker-x86.h"
31
#include "elf/i386.h"
32
#include "elf/x86-64.h"
33
#include "sframe-api.h"
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35
#define X86_64_PCREL_TYPE_P(TYPE) \
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0
  ((TYPE) == R_X86_64_PC8 \
37
0
   || (TYPE) == R_X86_64_PC16 \
38
0
   || (TYPE) == R_X86_64_PC32 \
39
0
   || (TYPE) == R_X86_64_PC64)
40
0
#define I386_PCREL_TYPE_P(TYPE) ((TYPE) == R_386_PC32)
41
#define X86_PCREL_TYPE_P(IS_X86_64, TYPE) \
42
0
  ((IS_X86_64) ? X86_64_PCREL_TYPE_P (TYPE) : I386_PCREL_TYPE_P (TYPE))
43
44
#define X86_64_SIZE_TYPE_P(TYPE) \
45
0
  ((TYPE) == R_X86_64_SIZE32 || (TYPE) == R_X86_64_SIZE64)
46
0
#define I386_SIZE_TYPE_P(TYPE) ((TYPE) == R_386_SIZE32)
47
#define X86_SIZE_TYPE_P(IS_X86_64, TYPE) \
48
0
  ((IS_X86_64) ? X86_64_SIZE_TYPE_P(TYPE) : I386_SIZE_TYPE_P (TYPE))
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50
#define X86_64_GOT_TYPE_P(TYPE) \
51
0
  ((TYPE) == R_X86_64_GOTPCREL \
52
0
   || (TYPE) == R_X86_64_GOTPCRELX \
53
0
   || (TYPE) == R_X86_64_REX_GOTPCRELX \
54
0
   || (TYPE) == R_X86_64_GOT32 \
55
0
   || (TYPE) == R_X86_64_GOT64 \
56
0
   || (TYPE) == R_X86_64_GOTPCREL64 \
57
0
   || (TYPE) == R_X86_64_GOTPLT64)
58
#define I386_GOT_TYPE_P(TYPE) \
59
0
  ((TYPE) == R_386_GOT32 || (TYPE) == R_386_GOT32X)
60
#define X86_GOT_TYPE_P(IS_X86_64, TYPE) \
61
0
  ((IS_X86_64) ? X86_64_GOT_TYPE_P (TYPE) : I386_GOT_TYPE_P (TYPE))
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63
#define X86_64_RELATIVE_RELOC_TYPE_P(TYPE) \
64
0
  (X86_64_PCREL_TYPE_P (TYPE) \
65
0
   || (TYPE) == R_X86_64_8 \
66
0
   || (TYPE) == R_X86_64_16 \
67
0
   || (TYPE) == R_X86_64_32 \
68
0
   || (TYPE) == R_X86_64_32S \
69
0
   || (TYPE) == R_X86_64_64)
70
#define I386_RELATIVE_RELOC_TYPE_P(TYPE) \
71
0
  ((TYPE) == R_386_32 || (TYPE) == R_386_PC32)
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#define X86_RELATIVE_RELOC_TYPE_P(IS_X86_64, TYPE) \
73
0
  ((IS_X86_64) \
74
0
   ? X86_64_RELATIVE_RELOC_TYPE_P (TYPE) \
75
0
   : I386_RELATIVE_RELOC_TYPE_P(TYPE))
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#define X86_64_NEED_DYNAMIC_RELOC_TYPE_P(TYPE) \
78
0
  (X86_64_SIZE_TYPE_P (TYPE) \
79
0
   || X86_64_RELATIVE_RELOC_TYPE_P (TYPE))
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#define I386_NEED_DYNAMIC_RELOC_TYPE_P(TYPE) \
81
0
  (I386_SIZE_TYPE_P (TYPE) \
82
0
   || I386_RELATIVE_RELOC_TYPE_P (TYPE) \
83
0
   || (TYPE) == R_386_TLS_IE \
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0
   || (TYPE) == R_386_TLS_LE \
85
0
   || (TYPE) == R_386_TLS_LE_32)
86
#define X86_NEED_DYNAMIC_RELOC_TYPE_P(IS_X86_64, TYPE) \
87
0
  ((IS_X86_64) \
88
0
   ? X86_64_NEED_DYNAMIC_RELOC_TYPE_P (TYPE) \
89
0
   : I386_NEED_DYNAMIC_RELOC_TYPE_P (TYPE))
90
91
#define X86_LOCAL_GOT_RELATIVE_RELOC_P(IS_X86_64, INFO, SYM) \
92
0
  (bfd_link_pic (INFO) \
93
0
   && (!(IS_X86_64) || ((SYM) != NULL && (SYM)->st_shndx != SHN_ABS)))
94
95
0
#define PLT_CIE_LENGTH    20
96
#define PLT_FDE_LENGTH    36
97
0
#define PLT_FDE_START_OFFSET  4 + PLT_CIE_LENGTH + 8
98
#define PLT_FDE_LEN_OFFSET  4 + PLT_CIE_LENGTH + 12
99
100
/* This must be the same as sframe_get_hdr_size (sfh).  For x86-64, this value
101
   is the same as sizeof (sframe_header) because there is no SFrame auxilliary
102
   header.  */
103
0
#define PLT_SFRAME_FDE_START_OFFSET sizeof (sframe_header)
104
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#define ABI_64_P(abfd) \
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65.9k
  (get_elf_backend_data (abfd)->s->elfclass == ELFCLASS64)
107
108
/* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
109
   copying dynamic variables from a shared lib into an app's dynbss
110
   section, and instead use a dynamic relocation to point into the
111
   shared lib.  */
112
0
#define ELIMINATE_COPY_RELOCS 1
113
114
#define elf_x86_hash_table(p, id) \
115
0
  (is_elf_hash_table ((p)->hash) \
116
0
   && elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) == (id) \
117
0
    ? ((struct elf_x86_link_hash_table *) ((p)->hash)) : NULL)
118
119
/* Will references to this symbol always be local in this object?  */
120
#define SYMBOL_REFERENCES_LOCAL_P(INFO, H) \
121
0
  _bfd_x86_elf_link_symbol_references_local ((INFO), (H))
122
123
/* TRUE if an undefined weak symbol should be resolved to 0.  Local
124
   undefined weak symbol is always resolved to 0.  Reference to an
125
   undefined weak symbol is resolved to 0 in executable if undefined
126
   weak symbol should be resolved to 0 (zero_undefweak > 0).  */
127
#define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, EH) \
128
0
  ((EH)->elf.root.type == bfd_link_hash_undefweak     \
129
0
   && (SYMBOL_REFERENCES_LOCAL_P ((INFO), &(EH)->elf)    \
130
0
       || (bfd_link_executable (INFO)        \
131
0
     && (EH)->zero_undefweak > 0)))
132
133
/* Should copy relocation be generated for a symbol.  Don't generate
134
   copy relocation against a protected symbol defined in a shared
135
   object.  */
136
#define SYMBOL_NO_COPYRELOC(INFO, EH) \
137
0
  ((EH)->def_protected \
138
0
   && ((EH)->elf.root.type == bfd_link_hash_defined \
139
0
       || (EH)->elf.root.type == bfd_link_hash_defweak) \
140
0
   && ((EH)->elf.root.u.def.section->owner->flags & DYNAMIC) != 0 \
141
0
   && ((EH)->elf.root.u.def.section->flags & SEC_CODE) == 0)
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143
/* TRUE if dynamic relocation is needed.  If we are creating a shared
144
   library, and this is a reloc against a global symbol, or a non PC
145
   relative reloc against a local symbol, then we need to copy the reloc
146
   into the shared library.  However, if we are linking with -Bsymbolic,
147
   we do not need to copy a reloc against a global symbol which is
148
   defined in an object we are including in the link (i.e., DEF_REGULAR
149
   is set).
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151
   If PCREL_PLT is true, don't generate dynamic relocation in PIE for
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   PC-relative relocation against a dynamic function definition in data
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   section when PLT address can be used.
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155
   If on the other hand, we are creating an executable, we may need to
156
   keep relocations for symbols satisfied by a dynamic library if we
157
   manage to avoid copy relocs for the symbol.
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   We also need to generate dynamic pointer relocation against
160
   STT_GNU_IFUNC symbol in the non-code section.  */
161
#define NEED_DYNAMIC_RELOCATION_P(IS_X86_64, INFO, PCREL_PLT, H, SEC, \
162
          R_TYPE, POINTER_TYPE) \
163
0
  ((bfd_link_pic (INFO) \
164
0
    && (! X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
165
0
  || ((H) != NULL \
166
0
      && (! (bfd_link_pie (INFO) \
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0
       || SYMBOLIC_BIND ((INFO), (H))) \
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0
    || (H)->root.type == bfd_link_hash_defweak \
169
0
    || (!(bfd_link_pie (INFO) \
170
0
          && (PCREL_PLT) \
171
0
          && (H)->plt.refcount > 0 \
172
0
          && ((SEC)->flags & SEC_CODE) == 0 \
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0
          && (H)->type == STT_FUNC \
174
0
          && (H)->def_dynamic) \
175
0
        && !(H)->def_regular))))) \
176
0
   || ((H) != NULL \
177
0
       && (H)->type == STT_GNU_IFUNC \
178
0
       && (R_TYPE) == POINTER_TYPE \
179
0
       && ((SEC)->flags & SEC_CODE) == 0) \
180
0
   || (ELIMINATE_COPY_RELOCS \
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0
       && !bfd_link_pic (INFO) \
182
0
       && (H) != NULL \
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0
       && ((H)->root.type == bfd_link_hash_defweak \
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0
     || !(H)->def_regular)))
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186
/* TRUE if dynamic relocation should be generated.  Don't copy a
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   pc-relative relocation into the output file if the symbol needs
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   copy reloc or the symbol is undefined when building executable.
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   Copy dynamic function pointer relocations.  Don't generate dynamic
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   relocations against resolved undefined weak symbols in PIE, except
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   when PC32_RELOC is TRUE.  Undefined weak symbol is bound locally
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   when PIC is false.  Don't generate dynamic relocations against
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   non-preemptible absolute symbol.  NB: rel_from_abs is set on symbols
194
   defined by linker scripts from "dot" (also SEGMENT_START or ORIGIN)
195
   outside of an output section statement, which will be converted from
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   absolute to section-relative in set_sym_sections called from
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   ldexp_finalize_syms after ldemul_finish.   */
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#define GENERATE_DYNAMIC_RELOCATION_P(IS_X86_64, INFO, EH, R_TYPE, \
199
              SEC, NEED_COPY_RELOC_IN_PIE, \
200
              RESOLVED_TO_ZERO, PC32_RELOC) \
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0
  ((bfd_link_pic (INFO) \
202
0
    && !(bfd_is_abs_section (SEC) \
203
0
   && ((EH) == NULL \
204
0
       || (EH)->elf.root.rel_from_abs == 0) \
205
0
   && ((EH) == NULL \
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0
       || SYMBOL_REFERENCES_LOCAL (INFO, &(EH)->elf))) \
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0
    && !(NEED_COPY_RELOC_IN_PIE) \
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0
    && ((EH) == NULL \
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0
  || ((ELF_ST_VISIBILITY ((EH)->elf.other) == STV_DEFAULT \
210
0
       && (!(RESOLVED_TO_ZERO) || PC32_RELOC)) \
211
0
      || (EH)->elf.root.type != bfd_link_hash_undefweak)) \
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0
    && ((!X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
213
0
   && !X86_SIZE_TYPE_P (IS_X86_64, R_TYPE)) \
214
0
  || ! SYMBOL_CALLS_LOCAL ((INFO), \
215
0
         (struct elf_link_hash_entry *) (EH)))) \
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0
   || (ELIMINATE_COPY_RELOCS \
217
0
       && !bfd_link_pic (INFO) \
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0
       && (EH) != NULL \
219
0
       && (EH)->elf.dynindx != -1 \
220
0
       && (!(EH)->elf.non_got_ref \
221
0
     || ((EH)->elf.root.type == bfd_link_hash_undefweak \
222
0
         && !(RESOLVED_TO_ZERO))) \
223
0
         && (((EH)->elf.def_dynamic && !(EH)->elf.def_regular) \
224
0
       || (EH)->elf.root.type == bfd_link_hash_undefined)))
225
226
/* TRUE if this input relocation should be copied to output.  H->dynindx
227
   may be -1 if this symbol was marked to become local.  */
228
#define COPY_INPUT_RELOC_P(IS_X86_64, INFO, H, R_TYPE) \
229
0
  ((H) != NULL \
230
0
   && (H)->dynindx != -1 \
231
0
   && (X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
232
0
       || !(bfd_link_executable (INFO) || SYMBOLIC_BIND ((INFO), (H))) \
233
0
       || !(H)->def_regular))
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235
/* TRUE if this is actually a static link, or it is a -Bsymbolic link
236
   and the symbol is defined locally, or the symbol was forced to be
237
   local because of a version file.  */
238
#define RESOLVED_LOCALLY_P(INFO, H, HTAB) \
239
0
  (!WILL_CALL_FINISH_DYNAMIC_SYMBOL ((HTAB)->elf.dynamic_sections_created, \
240
0
             bfd_link_pic (INFO), (H)) \
241
0
   || (bfd_link_pic (INFO) \
242
0
       && SYMBOL_REFERENCES_LOCAL_P ((INFO), (H))) \
243
0
       || (ELF_ST_VISIBILITY ((H)->other) \
244
0
     && (H)->root.type == bfd_link_hash_undefweak))
245
246
/* TRUE if this symbol isn't defined by a shared object.  */
247
#define SYMBOL_DEFINED_NON_SHARED_P(H) \
248
0
  ((H)->def_regular \
249
0
   || (H)->root.linker_def \
250
0
   || (H)->root.ldscript_def \
251
0
   || ((struct elf_x86_link_hash_entry *) (H))->linker_def \
252
0
   || ELF_COMMON_DEF_P (H))
253
254
/* Return TRUE if the symbol described by a linker hash entry H is
255
   going to be absolute.  Similar to bfd_is_abs_symbol, but excluding
256
   all linker-script defined symbols.  */
257
#define ABS_SYMBOL_P(H) \
258
0
  (bfd_is_abs_symbol (&(H)->root) && !(H)->root.ldscript_def)
259
260
/* TRUE if relative relocation should be generated.  GOT reference to
261
   global symbol in PIC will lead to dynamic symbol.  It becomes a
262
   problem when "time" or "times" is defined as a variable in an
263
   executable, clashing with functions of the same name in libc.  If a
264
   symbol isn't undefined weak symbol, don't make it dynamic in PIC and
265
   generate relative relocation.   Don't generate relative relocation
266
   against non-preemptible absolute symbol.  */
267
#define GENERATE_RELATIVE_RELOC_P(INFO, H) \
268
0
  ((H)->dynindx == -1 \
269
0
   && !(H)->forced_local \
270
0
   && (H)->root.type != bfd_link_hash_undefweak \
271
0
   && bfd_link_pic (INFO) \
272
0
   && !ABS_SYMBOL_P (H))
273
274
/* TRUE if this is a pointer reference to a local IFUNC.  */
275
#define POINTER_LOCAL_IFUNC_P(INFO, H) \
276
0
  ((H)->dynindx == -1 \
277
0
   || (H)->forced_local \
278
0
   || bfd_link_executable (INFO))
279
280
/* TRUE if this is a PLT reference to a local IFUNC.  */
281
#define PLT_LOCAL_IFUNC_P(INFO, H) \
282
0
  ((H)->dynindx == -1 \
283
0
   || ((bfd_link_executable (INFO) \
284
0
  || ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT) \
285
0
  && (H)->def_regular \
286
0
  && (H)->type == STT_GNU_IFUNC))
287
288
/* TRUE if TLS IE->LE transition is OK.  */
289
#define TLS_TRANSITION_IE_TO_LE_P(INFO, H, TLS_TYPE) \
290
0
  (bfd_link_executable (INFO) \
291
0
   && (H) != NULL \
292
0
   && (H)->dynindx == -1 \
293
0
   && (TLS_TYPE & GOT_TLS_IE))
294
295
/* Verify that the symbol has an entry in the procedure linkage table.  */
296
#define VERIFY_PLT_ENTRY(INFO, H, PLT, GOTPLT, RELPLT, LOCAL_UNDEFWEAK) \
297
0
  do \
298
0
    { \
299
0
      if (((H)->dynindx == -1 \
300
0
     && !LOCAL_UNDEFWEAK \
301
0
     && !(((H)->forced_local || bfd_link_executable (INFO)) \
302
0
    && (H)->def_regular \
303
0
    && (H)->type == STT_GNU_IFUNC)) \
304
0
    || (PLT) == NULL \
305
0
    || (GOTPLT) == NULL \
306
0
    || (RELPLT) == NULL) \
307
0
  abort (); \
308
0
    } \
309
0
  while (0);
310
311
/* Verify that the symbol supports copy relocation.  */
312
#define VERIFY_COPY_RELOC(H, HTAB) \
313
0
  do \
314
0
    { \
315
0
      if ((H)->dynindx == -1 \
316
0
    || ((H)->root.type != bfd_link_hash_defined \
317
0
        && (H)->root.type != bfd_link_hash_defweak) \
318
0
    || (HTAB)->elf.srelbss == NULL \
319
0
    || (HTAB)->elf.sreldynrelro == NULL) \
320
0
  abort (); \
321
0
    } \
322
0
  while (0);
323
324
/* x86 ELF linker hash entry.  */
325
326
struct elf_x86_link_hash_entry
327
{
328
  struct elf_link_hash_entry elf;
329
330
  unsigned char tls_type;
331
332
  /* Bit 0: Symbol has no GOT nor PLT relocations.
333
     Bit 1: Symbol has non-GOT/non-PLT relocations in text sections.
334
     zero_undefweak is initialized to 1 and undefined weak symbol
335
     should be resolved to 0 if zero_undefweak > 0.  */
336
  unsigned int zero_undefweak : 2;
337
338
  /* Don't call finish_dynamic_symbol on this symbol.  */
339
  unsigned int no_finish_dynamic_symbol : 1;
340
341
  /* R_*_RELATIVE relocation in GOT for this symbol has been
342
     processed.  */
343
  unsigned int got_relative_reloc_done : 1;
344
345
  /* TRUE if symbol is __tls_get_addr.  */
346
  unsigned int tls_get_addr : 1;
347
348
  /* TRUE if symbol is defined as a protected symbol.  */
349
  unsigned int def_protected : 1;
350
351
  /* 0: Symbol references are unknown.
352
     1: Symbol references aren't local.
353
     2: Symbol references are local.
354
   */
355
  unsigned int local_ref : 2;
356
357
  /* TRUE if symbol is defined by linker.  */
358
  unsigned int linker_def : 1;
359
360
  /* TRUE if symbol is referenced by a non-GOT/non-PLT relocation in a
361
     relocatable object file without indirect external access marker.  */
362
  unsigned int non_got_ref_without_indirect_extern_access : 1;
363
364
  /* TRUE if symbol is referenced by R_386_GOTOFF relocation.  This is
365
     only used by i386.  */
366
  unsigned int gotoff_ref : 1;
367
368
  /* TRUE if a weak symbol with a real definition needs a copy reloc.
369
     When there is a weak symbol with a real definition, the processor
370
     independent code will have arranged for us to see the real
371
     definition first.  We need to copy the needs_copy bit from the
372
     real definition and check it when allowing copy reloc in PIE.  This
373
     is only used by x86-64.  */
374
  unsigned int needs_copy : 1;
375
376
  /* Information about the GOT PLT entry. Filled when there are both
377
     GOT and PLT relocations against the same function.  */
378
  union gotplt_union plt_got;
379
380
  /* Information about the second PLT entry.   */
381
  union gotplt_union plt_second;
382
383
  /* Offset of the GOTPLT entry reserved for the TLS descriptor,
384
     starting at the end of the jump table.  */
385
  bfd_vma tlsdesc_got;
386
};
387
388
#define SFRAME_PLT0_MAX_NUM_FRES 2
389
#define SFRAME_PLTN_MAX_NUM_FRES 2
390
391
struct elf_x86_sframe_plt
392
{
393
  unsigned int plt0_entry_size;
394
  unsigned int plt0_num_fres;
395
  const sframe_frame_row_entry *plt0_fres[SFRAME_PLT0_MAX_NUM_FRES];
396
397
  unsigned int pltn_entry_size;
398
  unsigned int pltn_num_fres;
399
  const sframe_frame_row_entry *pltn_fres[SFRAME_PLTN_MAX_NUM_FRES];
400
401
  unsigned int sec_pltn_entry_size;
402
  unsigned int sec_pltn_num_fres;
403
  const sframe_frame_row_entry *sec_pltn_fres[SFRAME_PLTN_MAX_NUM_FRES];
404
};
405
406
struct elf_x86_lazy_plt_layout
407
{
408
  /* The first entry in a lazy procedure linkage table looks like this.  */
409
  const bfd_byte *plt0_entry;
410
  unsigned int plt0_entry_size;    /* Size of PLT0 entry.  */
411
412
  /* Later entries in a lazy procedure linkage table look like this.  */
413
  const bfd_byte *plt_entry;
414
  unsigned int plt_entry_size;    /* Size of each PLT entry.  */
415
416
  /* The TLSDESC entry in a lazy procedure linkage table looks like
417
     this.  This is for x86-64 only.  */
418
  const bfd_byte *plt_tlsdesc_entry;
419
  unsigned int plt_tlsdesc_entry_size;   /* Size of TLSDESC entry.  */
420
421
  /* Offsets into the TLSDESC entry that are to be replaced with
422
     GOT+8 and GOT+TDG.  These are for x86-64 only.  */
423
  unsigned int plt_tlsdesc_got1_offset;
424
  unsigned int plt_tlsdesc_got2_offset;
425
426
  /* Offset of the end of the PC-relative instructions containing
427
     plt_tlsdesc_got1_offset and plt_tlsdesc_got2_offset.  These
428
     are for x86-64 only.  */
429
  unsigned int plt_tlsdesc_got1_insn_end;
430
  unsigned int plt_tlsdesc_got2_insn_end;
431
432
  /* Offsets into plt0_entry that are to be replaced with GOT[1] and
433
     GOT[2].  */
434
  unsigned int plt0_got1_offset;
435
  unsigned int plt0_got2_offset;
436
437
  /* Offset of the end of the PC-relative instruction containing
438
     plt0_got2_offset.  This is for x86-64 only.  */
439
  unsigned int plt0_got2_insn_end;
440
441
  /* Offsets into plt_entry that are to be replaced with...  */
442
  unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
443
  unsigned int plt_reloc_offset;  /* ... offset into relocation table. */
444
  unsigned int plt_plt_offset;    /* ... offset to start of .plt. */
445
446
  /* Length of the PC-relative instruction containing plt_got_offset.
447
     This is used for x86-64 only.  */
448
  unsigned int plt_got_insn_size;
449
450
  /* Offset of the end of the PC-relative jump to plt0_entry.  This is
451
     used for x86-64 only.  */
452
  unsigned int plt_plt_insn_end;
453
454
  /* Offset into plt_entry where the initial value of the GOT entry
455
     points.  */
456
  unsigned int plt_lazy_offset;
457
458
  /* The first entry in a PIC lazy procedure linkage table looks like
459
     this.  */
460
  const bfd_byte *pic_plt0_entry;
461
462
  /* Subsequent entries in a PIC lazy procedure linkage table look
463
     like this.  */
464
  const bfd_byte *pic_plt_entry;
465
466
  /* .eh_frame covering the lazy .plt section.  */
467
  const bfd_byte *eh_frame_plt;
468
  unsigned int eh_frame_plt_size;
469
};
470
471
struct elf_x86_non_lazy_plt_layout
472
{
473
  /* Entries in a non-lazy procedure linkage table look like this.  */
474
  const bfd_byte *plt_entry;
475
  /* Entries in a PIC non-lazy procedure linkage table look like this.
476
     This is only used for i386 where absolute PLT and PIC PLT are
477
     different.  */
478
  const bfd_byte *pic_plt_entry;
479
480
  unsigned int plt_entry_size;    /* Size of each PLT entry.  */
481
482
  /* Offsets into plt_entry that are to be replaced with...  */
483
  unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
484
485
  /* Length of the PC-relative instruction containing plt_got_offset.
486
     This is used for x86-64 only.  */
487
  unsigned int plt_got_insn_size;
488
489
  /* .eh_frame covering the non-lazy .plt section.  */
490
  const bfd_byte *eh_frame_plt;
491
  unsigned int eh_frame_plt_size;
492
};
493
494
struct elf_x86_plt_layout
495
{
496
  /* The first entry in a lazy procedure linkage table looks like this.  */
497
  const bfd_byte *plt0_entry;
498
  /* Entries in a procedure linkage table look like this.  */
499
  const bfd_byte *plt_entry;
500
  unsigned int plt_entry_size;    /* Size of each PLT entry.  */
501
502
  /* 1 has PLT0.  */
503
  unsigned int has_plt0;
504
505
  /* Offset of indirect branch in plt_entry.  */
506
  unsigned int plt_indirect_branch_offset;
507
508
  /* Offsets into plt_entry that are to be replaced with...  */
509
  unsigned int plt_got_offset;    /* ... address of this symbol in .got. */
510
511
  /* Length of the PC-relative instruction containing plt_got_offset.
512
     This is only used for x86-64.  */
513
  unsigned int plt_got_insn_size;
514
515
  /* Alignment of the .iplt section.  */
516
  unsigned int iplt_alignment;
517
518
  /* .eh_frame covering the .plt section.  */
519
  const bfd_byte *eh_frame_plt;
520
  unsigned int eh_frame_plt_size;
521
};
522
523
/* Values in tls_type of x86 ELF linker hash entry.  */
524
0
#define GOT_UNKNOWN 0
525
0
#define GOT_NORMAL  1
526
0
#define GOT_TLS_GD  2
527
0
#define GOT_TLS_IE  4
528
0
#define GOT_TLS_IE_POS  5
529
0
#define GOT_TLS_IE_NEG  6
530
0
#define GOT_TLS_IE_BOTH 7
531
0
#define GOT_TLS_GDESC 8
532
0
#define GOT_ABS   9
533
#define GOT_TLS_GD_BOTH_P(type) \
534
0
  ((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
535
#define GOT_TLS_GD_P(type) \
536
0
  ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
537
#define GOT_TLS_GDESC_P(type) \
538
0
  ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
539
#define GOT_TLS_GD_ANY_P(type) \
540
0
  (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
541
542
#define elf_x86_hash_entry(ent) \
543
0
  ((struct elf_x86_link_hash_entry *)(ent))
544
545
/* Information of an input relocation used to compute its contribution
546
   to the DT_RELR section size.  */
547
548
struct elf_x86_relative_reloc_record
549
{
550
  /* The original relocation info.  */
551
  Elf_Internal_Rela rel;
552
  /* The input or the GOT section where the relocation is applied.  */
553
  asection *sec;
554
  /* Local symbol info.  NULL for global symbol.  */
555
  Elf_Internal_Sym *sym;
556
  union
557
    {
558
      /* Section where the local symbol is defined.  */
559
      asection *sym_sec;
560
      /* Global symbol hash.  */
561
      struct elf_link_hash_entry *h;
562
    } u;
563
  /* The offset into the output section where the relative relocation
564
     will be applied at run-time.  */
565
  bfd_vma offset;
566
  /* The run-time address.  */
567
  bfd_vma address;
568
};
569
570
struct elf_x86_relative_reloc_data
571
{
572
  bfd_size_type count;
573
  bfd_size_type size;
574
  struct elf_x86_relative_reloc_record *data;
575
};
576
577
/* DT_RELR bitmap.  */
578
struct elf_dt_relr_bitmap
579
{
580
  bfd_size_type count;
581
  bfd_size_type size;
582
  union
583
    {
584
      /* 32-bit bitmap.  */
585
      uint32_t *elf32;
586
      /* 64-bit bitmap.  */
587
      uint64_t *elf64;
588
    } u;
589
};
590
591
/* x86 ELF linker hash table.  */
592
593
struct elf_x86_link_hash_table
594
{
595
  struct elf_link_hash_table elf;
596
597
  /* Short-cuts to get to dynamic linker sections.  */
598
  asection *interp;
599
  asection *plt_eh_frame;
600
  asection *plt_second;
601
  asection *plt_second_eh_frame;
602
  asection *plt_got;
603
  asection *plt_got_eh_frame;
604
605
  sframe_encoder_ctx *plt_cfe_ctx;
606
  asection *plt_sframe;
607
  sframe_encoder_ctx *plt_second_cfe_ctx;
608
  asection *plt_second_sframe;
609
610
  /* Parameters describing PLT generation, lazy or non-lazy.  */
611
  struct elf_x86_plt_layout plt;
612
613
  /* Parameters describing lazy PLT generation.  */
614
  const struct elf_x86_lazy_plt_layout *lazy_plt;
615
616
  /* Parameters describing non-lazy PLT generation.  */
617
  const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
618
619
  /* The .sframe helper object for .plt section.
620
     This is used for x86-64 only.  */
621
  const struct elf_x86_sframe_plt *sframe_plt;
622
623
  union
624
  {
625
    bfd_signed_vma refcount;
626
    bfd_vma offset;
627
  } tls_ld_or_ldm_got;
628
629
  /* The amount of space used by the jump slots in the GOT.  */
630
  bfd_vma sgotplt_jump_table_size;
631
632
  /* _TLS_MODULE_BASE_ symbol.  */
633
  struct bfd_link_hash_entry *tls_module_base;
634
635
  /* Used by local STT_GNU_IFUNC symbols.  */
636
  htab_t loc_hash_table;
637
  void * loc_hash_memory;
638
639
  /* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt.  */
640
  bfd_vma next_jump_slot_index;
641
  /* The index of the next R_X86_64_IRELATIVE entry in .rela.plt.  */
642
  bfd_vma next_irelative_index;
643
644
  /* The (unloaded but important) .rel.plt.unloaded section on VxWorks.
645
     This is used for i386 only.  */
646
  asection *srelplt2;
647
648
  /* The index of the next unused R_386_TLS_DESC slot in .rel.plt.  This
649
     is only used for i386.  */
650
  bfd_vma next_tls_desc_index;
651
652
  /* DT_RELR bitmap.  */
653
  struct elf_dt_relr_bitmap dt_relr_bitmap;
654
655
  /* Relative relocation data.  */
656
  struct elf_x86_relative_reloc_data relative_reloc;
657
658
  /* Unaligned relative relocation data.  */
659
  struct elf_x86_relative_reloc_data unaligned_relative_reloc;
660
661
  /* Number of relative reloc generation pass.  */
662
  unsigned int generate_relative_reloc_pass;
663
664
   /* Value used to fill the unused bytes of the first PLT entry.  This
665
      is only used for i386.  */
666
  bfd_byte plt0_pad_byte;
667
668
  /* TRUE if GOT is referenced.  */
669
  unsigned int got_referenced : 1;
670
671
  /* TRUE if PLT is PC-relative.  PLT in PDE and PC-relative PLT in PIE
672
     can be used as function address.
673
674
     NB: i386 has non-PIC PLT and PIC PLT.  Only non-PIC PLT in PDE can
675
     be used as function address.  PIC PLT in PIE can't be used as
676
     function address.  */
677
  unsigned int pcrel_plt : 1;
678
679
  bfd_vma (*r_info) (bfd_vma, bfd_vma);
680
  bfd_vma (*r_sym) (bfd_vma);
681
  bool (*is_reloc_section) (const char *);
682
  unsigned int sizeof_reloc;
683
  unsigned int got_entry_size;
684
  unsigned int pointer_r_type;
685
  unsigned int relative_r_type;
686
  int dynamic_interpreter_size;
687
  const char *dynamic_interpreter;
688
  const char *tls_get_addr;
689
  const char *relative_r_name;
690
  void (*elf_append_reloc) (bfd *, asection *, Elf_Internal_Rela *);
691
  void (*elf_write_addend) (bfd *, uint64_t, void *);
692
  void (*elf_write_addend_in_got) (bfd *, uint64_t, void *);
693
694
  /* Options passed from the linker.  */
695
  struct elf_linker_x86_params *params;
696
};
697
698
struct elf_x86_init_table
699
{
700
  /* The lazy PLT layout.  */
701
  const struct elf_x86_lazy_plt_layout *lazy_plt;
702
703
  /* The non-lazy PLT layout.  */
704
  const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
705
706
  /* The lazy PLT layout for IBT.  */
707
  const struct elf_x86_lazy_plt_layout *lazy_ibt_plt;
708
709
  /* The non-lazy PLT layout for IBT.  */
710
  const struct elf_x86_non_lazy_plt_layout *non_lazy_ibt_plt;
711
712
  /* The .sframe helper object for lazy .plt section.
713
     This is used for x86-64 only.  */
714
  const struct elf_x86_sframe_plt *sframe_lazy_plt;
715
716
  /* The .sframe helper object for non-lazy .plt section.
717
     This is used for x86-64 only.  */
718
  const struct elf_x86_sframe_plt *sframe_non_lazy_plt;
719
720
  /* The .sframe helper object for lazy IBT .plt section.
721
     This is used for x86-64 only.  */
722
  const struct elf_x86_sframe_plt *sframe_lazy_ibt_plt;
723
724
  /* The .sframe helper object for non-lazy IBT .plt section.
725
     This is used for x86-64 only.  */
726
  const struct elf_x86_sframe_plt *sframe_non_lazy_ibt_plt;
727
728
  bfd_byte plt0_pad_byte;
729
730
  bfd_vma (*r_info) (bfd_vma, bfd_vma);
731
  bfd_vma (*r_sym) (bfd_vma);
732
};
733
734
struct elf_x86_obj_tdata
735
{
736
  struct elf_obj_tdata root;
737
738
  /* tls_type for each local got entry.  */
739
  char *local_got_tls_type;
740
741
  /* GOTPLT entries for TLS descriptors.  */
742
  bfd_vma *local_tlsdesc_gotent;
743
744
  /* R_*_RELATIVE relocation in GOT for this local symbol has been
745
     processed.  */
746
  char *relative_reloc_done;
747
};
748
749
enum elf_x86_plt_type
750
{
751
  plt_non_lazy = 0,
752
  plt_lazy = 1 << 0,
753
  plt_pic = 1 << 1,
754
  plt_second = 1 << 2,
755
  plt_unknown = -1
756
};
757
758
struct elf_x86_plt
759
{
760
  const char *name;
761
  asection *sec;
762
  bfd_byte *contents;
763
  enum elf_x86_plt_type type;
764
  unsigned int plt_got_offset;
765
  unsigned int plt_entry_size;
766
  unsigned int plt_got_insn_size; /* Only used for x86-64.  */
767
  long count;
768
};
769
770
/* Set if a relocation is converted from a GOTPCREL relocation.  */
771
0
#define R_X86_64_converted_reloc_bit (1 << 7)
772
773
#define elf_x86_tdata(abfd) \
774
0
  ((struct elf_x86_obj_tdata *) (abfd)->tdata.any)
775
776
#define elf_x86_local_got_tls_type(abfd) \
777
0
  (elf_x86_tdata (abfd)->local_got_tls_type)
778
779
#define elf_x86_local_tlsdesc_gotent(abfd) \
780
0
  (elf_x86_tdata (abfd)->local_tlsdesc_gotent)
781
782
#define elf_x86_relative_reloc_done(abfd) \
783
0
  (elf_x86_tdata (abfd)->relative_reloc_done)
784
785
#define elf_x86_compute_jump_table_size(htab) \
786
0
  ((htab)->elf.srelplt->reloc_count * (htab)->got_entry_size)
787
788
#define is_x86_elf(bfd, htab)       \
789
0
  (bfd_get_flavour (bfd) == bfd_target_elf_flavour  \
790
0
   && elf_tdata (bfd) != NULL        \
791
0
   && elf_object_id (bfd) == (htab)->elf.hash_table_id)
792
793
/* Rename some of the generic section flags to better document how they
794
   are used here.  */
795
0
#define check_relocs_failed sec_flg0
796
0
#define relative_reloc_packed sec_flg1
797
798
extern bool _bfd_x86_elf_mkobject
799
  (bfd *) ATTRIBUTE_HIDDEN;
800
801
extern void _bfd_x86_elf_set_tls_module_base
802
  (struct bfd_link_info *) ATTRIBUTE_HIDDEN;
803
804
extern bfd_vma _bfd_x86_elf_dtpoff_base
805
  (struct bfd_link_info *) ATTRIBUTE_HIDDEN;
806
807
extern bool _bfd_x86_elf_readonly_dynrelocs
808
  (struct elf_link_hash_entry *, void *) ATTRIBUTE_HIDDEN;
809
810
extern struct elf_link_hash_entry * _bfd_elf_x86_get_local_sym_hash
811
  (struct elf_x86_link_hash_table *, bfd *, const Elf_Internal_Rela *,
812
   bool) ATTRIBUTE_HIDDEN;
813
814
extern hashval_t _bfd_x86_elf_local_htab_hash
815
  (const void *) ATTRIBUTE_HIDDEN;
816
817
extern int _bfd_x86_elf_local_htab_eq
818
  (const void *, const void *) ATTRIBUTE_HIDDEN;
819
820
extern struct bfd_hash_entry * _bfd_x86_elf_link_hash_newfunc
821
  (struct bfd_hash_entry *, struct bfd_hash_table *, const char *)
822
  ATTRIBUTE_HIDDEN;
823
824
extern struct bfd_link_hash_table * _bfd_x86_elf_link_hash_table_create
825
  (bfd *) ATTRIBUTE_HIDDEN;
826
827
extern int _bfd_x86_elf_compare_relocs
828
  (const void *, const void *) ATTRIBUTE_HIDDEN;
829
830
extern bool _bfd_x86_elf_link_check_relocs
831
  (bfd *, struct bfd_link_info *) ATTRIBUTE_HIDDEN;
832
833
extern bool _bfd_x86_elf_check_relocs
834
  (bfd *, struct bfd_link_info *, asection *,
835
   const Elf_Internal_Rela *) ATTRIBUTE_HIDDEN;
836
837
extern bool _bfd_x86_elf_link_relax_section
838
  (bfd *, asection *, struct bfd_link_info *, bool *) ATTRIBUTE_HIDDEN;
839
840
extern bool _bfd_elf_x86_size_relative_relocs
841
  (struct bfd_link_info *, bool *) ATTRIBUTE_HIDDEN;
842
843
extern bool _bfd_elf_x86_finish_relative_relocs
844
  (struct bfd_link_info *) ATTRIBUTE_HIDDEN;
845
846
extern void _bfd_elf32_write_addend 
847
  (bfd *, uint64_t, void *) ATTRIBUTE_HIDDEN;
848
extern void _bfd_elf64_write_addend
849
  (bfd *, uint64_t, void *) ATTRIBUTE_HIDDEN;
850
851
extern bool _bfd_elf_x86_valid_reloc_p
852
  (asection *, struct bfd_link_info *, struct elf_x86_link_hash_table *,
853
   const Elf_Internal_Rela *, struct elf_link_hash_entry *,
854
   Elf_Internal_Sym *, Elf_Internal_Shdr *, bool *) ATTRIBUTE_HIDDEN;
855
856
extern bool _bfd_x86_elf_late_size_sections
857
  (bfd *, struct bfd_link_info *) ATTRIBUTE_HIDDEN;
858
859
extern struct elf_x86_link_hash_table *_bfd_x86_elf_finish_dynamic_sections
860
  (bfd *, struct bfd_link_info *) ATTRIBUTE_HIDDEN;
861
862
extern bool _bfd_x86_elf_early_size_sections
863
  (bfd *, struct bfd_link_info *) ATTRIBUTE_HIDDEN;
864
865
extern void _bfd_x86_elf_merge_symbol_attribute
866
  (struct elf_link_hash_entry *, unsigned int, bool, bool)
867
  ATTRIBUTE_HIDDEN;
868
869
extern void _bfd_x86_elf_copy_indirect_symbol
870
  (struct bfd_link_info *, struct elf_link_hash_entry *,
871
   struct elf_link_hash_entry *) ATTRIBUTE_HIDDEN;
872
873
extern bool _bfd_x86_elf_fixup_symbol
874
  (struct bfd_link_info *, struct elf_link_hash_entry *) ATTRIBUTE_HIDDEN;
875
876
extern bool _bfd_x86_elf_hash_symbol
877
  (struct elf_link_hash_entry *) ATTRIBUTE_HIDDEN;
878
879
extern bool _bfd_x86_elf_adjust_dynamic_symbol
880
  (struct bfd_link_info *, struct elf_link_hash_entry *) ATTRIBUTE_HIDDEN;
881
882
extern void _bfd_x86_elf_hide_symbol
883
  (struct bfd_link_info *, struct elf_link_hash_entry *,
884
   bool) ATTRIBUTE_HIDDEN;
885
886
extern bool _bfd_x86_elf_link_symbol_references_local
887
  (struct bfd_link_info *, struct elf_link_hash_entry *) ATTRIBUTE_HIDDEN;
888
889
extern asection * _bfd_x86_elf_gc_mark_hook
890
  (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
891
   struct elf_link_hash_entry *, Elf_Internal_Sym *) ATTRIBUTE_HIDDEN;
892
893
extern long _bfd_x86_elf_get_synthetic_symtab
894
  (bfd *, long, long, bfd_vma, struct elf_x86_plt [], asymbol **,
895
   asymbol **) ATTRIBUTE_HIDDEN;
896
897
extern enum elf_property_kind _bfd_x86_elf_parse_gnu_properties
898
  (bfd *, unsigned int, bfd_byte *, unsigned int) ATTRIBUTE_HIDDEN;
899
900
extern bool _bfd_x86_elf_merge_gnu_properties
901
  (struct bfd_link_info *, bfd *, bfd *, elf_property *, elf_property *)
902
  ATTRIBUTE_HIDDEN;
903
904
extern void _bfd_x86_elf_link_fixup_gnu_properties
905
  (struct bfd_link_info *, elf_property_list **) ATTRIBUTE_HIDDEN;
906
907
extern bfd * _bfd_x86_elf_link_setup_gnu_properties
908
  (struct bfd_link_info *, struct elf_x86_init_table *) ATTRIBUTE_HIDDEN;
909
910
extern void _bfd_x86_elf_link_fixup_ifunc_symbol
911
  (struct bfd_link_info *, struct elf_x86_link_hash_table *,
912
   struct elf_link_hash_entry *, Elf_Internal_Sym *sym) ATTRIBUTE_HIDDEN;
913
914
extern void _bfd_x86_elf_link_report_relative_reloc
915
  (struct bfd_link_info *, asection *, struct elf_link_hash_entry *,
916
   Elf_Internal_Sym *, const char *, const void *) ATTRIBUTE_HIDDEN;
917
918
#define bfd_elf64_mkobject \
919
  _bfd_x86_elf_mkobject
920
#define bfd_elf32_mkobject \
921
  _bfd_x86_elf_mkobject
922
#define bfd_elf64_bfd_link_hash_table_create \
923
  _bfd_x86_elf_link_hash_table_create
924
#define bfd_elf32_bfd_link_hash_table_create \
925
  _bfd_x86_elf_link_hash_table_create
926
#define bfd_elf64_bfd_link_check_relocs \
927
  _bfd_x86_elf_link_check_relocs
928
#define bfd_elf32_bfd_link_check_relocs \
929
  _bfd_x86_elf_link_check_relocs
930
#define bfd_elf32_bfd_relax_section \
931
  _bfd_x86_elf_link_relax_section
932
#define bfd_elf64_bfd_relax_section \
933
  _bfd_x86_elf_link_relax_section
934
935
#define elf_backend_check_relocs \
936
  _bfd_x86_elf_check_relocs
937
#define elf_backend_late_size_sections \
938
  _bfd_x86_elf_late_size_sections
939
#define elf_backend_merge_symbol_attribute \
940
  _bfd_x86_elf_merge_symbol_attribute
941
#define elf_backend_copy_indirect_symbol \
942
  _bfd_x86_elf_copy_indirect_symbol
943
#define elf_backend_fixup_symbol \
944
  _bfd_x86_elf_fixup_symbol
945
#define elf_backend_hash_symbol \
946
  _bfd_x86_elf_hash_symbol
947
#define elf_backend_adjust_dynamic_symbol \
948
  _bfd_x86_elf_adjust_dynamic_symbol
949
#define elf_backend_gc_mark_hook \
950
  _bfd_x86_elf_gc_mark_hook
951
#define elf_backend_omit_section_dynsym \
952
  _bfd_elf_omit_section_dynsym_all
953
#define elf_backend_parse_gnu_properties \
954
  _bfd_x86_elf_parse_gnu_properties
955
#define elf_backend_merge_gnu_properties \
956
  _bfd_x86_elf_merge_gnu_properties
957
#define elf_backend_fixup_gnu_properties \
958
  _bfd_x86_elf_link_fixup_gnu_properties
959
#define elf_backend_size_relative_relocs \
960
  _bfd_elf_x86_size_relative_relocs
961
#define elf_backend_finish_relative_relocs \
962
  _bfd_elf_x86_finish_relative_relocs
963
#define elf_backend_use_mmap true
964
965
#define ELF_P_ALIGN ELF_MINPAGESIZE
966
967
/* Allocate x86 GOT info for local symbols.  */
968
969
static inline bool
970
elf_x86_allocate_local_got_info (bfd *abfd, bfd_size_type count)
971
0
{
972
0
  bfd_signed_vma *local_got_refcounts = elf_local_got_refcounts (abfd);
973
0
  if (local_got_refcounts == NULL)
974
0
    {
975
0
      bfd_size_type size = count * (sizeof (bfd_signed_vma)
976
0
            + sizeof (bfd_vma)
977
0
            + 2 * sizeof(char));
978
0
      local_got_refcounts = (bfd_signed_vma *) bfd_zalloc (abfd, size);
979
0
      if (local_got_refcounts == NULL)
980
0
  return false;
981
0
      elf_local_got_refcounts (abfd) = local_got_refcounts;
982
0
      elf_x86_local_tlsdesc_gotent (abfd) =
983
0
  (bfd_vma *) (local_got_refcounts + count);
984
0
      elf_x86_local_got_tls_type (abfd) =
985
0
  (char *) (local_got_refcounts + 2 * count);
986
0
      elf_x86_relative_reloc_done (abfd) =
987
0
  ((char *) (local_got_refcounts + 2 * count)) + count;
988
0
    }
989
0
  return true;
990
0
}
Unexecuted instantiation: elf64-x86-64.c:elf_x86_allocate_local_got_info
Unexecuted instantiation: elfxx-x86.c:elf_x86_allocate_local_got_info
Unexecuted instantiation: elf32-i386.c:elf_x86_allocate_local_got_info