readelf: Add option to display the names of sections referenced by symbols.
[binutils-gdb.git] / bfd / elfxx-x86.h
blob3b4644ca4789465404625dbdba6b798866b0abec
1 /* x86 specific support for ELF
2 Copyright (C) 2017-2023 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
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.
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.
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. */
21 /* Don't generate unused section symbols. */
22 #define TARGET_KEEP_UNUSED_SECTION_SYMBOLS false
24 #include "sysdep.h"
25 #include "bfd.h"
26 #include "bfdlink.h"
27 #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"
35 #define X86_64_PCREL_TYPE_P(TYPE) \
36 ((TYPE) == R_X86_64_PC8 \
37 || (TYPE) == R_X86_64_PC16 \
38 || (TYPE) == R_X86_64_PC32 \
39 || (TYPE) == R_X86_64_PC64)
40 #define I386_PCREL_TYPE_P(TYPE) ((TYPE) == R_386_PC32)
41 #define X86_PCREL_TYPE_P(IS_X86_64, TYPE) \
42 ((IS_X86_64) ? X86_64_PCREL_TYPE_P (TYPE) : I386_PCREL_TYPE_P (TYPE))
44 #define X86_64_SIZE_TYPE_P(TYPE) \
45 ((TYPE) == R_X86_64_SIZE32 || (TYPE) == R_X86_64_SIZE64)
46 #define I386_SIZE_TYPE_P(TYPE) ((TYPE) == R_386_SIZE32)
47 #define X86_SIZE_TYPE_P(IS_X86_64, TYPE) \
48 ((IS_X86_64) ? X86_64_SIZE_TYPE_P(TYPE) : I386_SIZE_TYPE_P (TYPE))
50 #define X86_64_GOT_TYPE_P(TYPE) \
51 ((TYPE) == R_X86_64_GOTPCREL \
52 || (TYPE) == R_X86_64_GOTPCRELX \
53 || (TYPE) == R_X86_64_REX_GOTPCRELX \
54 || (TYPE) == R_X86_64_GOT32 \
55 || (TYPE) == R_X86_64_GOT64 \
56 || (TYPE) == R_X86_64_GOTPCREL64 \
57 || (TYPE) == R_X86_64_GOTPLT64)
58 #define I386_GOT_TYPE_P(TYPE) \
59 ((TYPE) == R_386_GOT32 || (TYPE) == R_386_GOT32X)
60 #define X86_GOT_TYPE_P(IS_X86_64, TYPE) \
61 ((IS_X86_64) ? X86_64_GOT_TYPE_P (TYPE) : I386_GOT_TYPE_P (TYPE))
63 #define X86_64_RELATIVE_RELOC_TYPE_P(TYPE) \
64 (X86_64_PCREL_TYPE_P (TYPE) \
65 || (TYPE) == R_X86_64_8 \
66 || (TYPE) == R_X86_64_16 \
67 || (TYPE) == R_X86_64_32 \
68 || (TYPE) == R_X86_64_32S \
69 || (TYPE) == R_X86_64_64)
70 #define I386_RELATIVE_RELOC_TYPE_P(TYPE) \
71 ((TYPE) == R_386_32 || (TYPE) == R_386_PC32)
72 #define X86_RELATIVE_RELOC_TYPE_P(IS_X86_64, TYPE) \
73 ((IS_X86_64) \
74 ? X86_64_RELATIVE_RELOC_TYPE_P (TYPE) \
75 : I386_RELATIVE_RELOC_TYPE_P(TYPE))
77 #define X86_64_NEED_DYNAMIC_RELOC_TYPE_P(TYPE) \
78 (X86_64_SIZE_TYPE_P (TYPE) \
79 || X86_64_RELATIVE_RELOC_TYPE_P (TYPE))
80 #define I386_NEED_DYNAMIC_RELOC_TYPE_P(TYPE) \
81 (I386_SIZE_TYPE_P (TYPE) \
82 || I386_RELATIVE_RELOC_TYPE_P (TYPE) \
83 || (TYPE) == R_386_TLS_IE \
84 || (TYPE) == R_386_TLS_LE \
85 || (TYPE) == R_386_TLS_LE_32)
86 #define X86_NEED_DYNAMIC_RELOC_TYPE_P(IS_X86_64, TYPE) \
87 ((IS_X86_64) \
88 ? X86_64_NEED_DYNAMIC_RELOC_TYPE_P (TYPE) \
89 : I386_NEED_DYNAMIC_RELOC_TYPE_P (TYPE))
91 #define X86_LOCAL_GOT_RELATIVE_RELOC_P(IS_X86_64, INFO, SYM) \
92 (bfd_link_pic (INFO) \
93 && (!(IS_X86_64) || ((SYM) != NULL && (SYM)->st_shndx != SHN_ABS)))
95 #define PLT_CIE_LENGTH 20
96 #define PLT_FDE_LENGTH 36
97 #define PLT_FDE_START_OFFSET 4 + PLT_CIE_LENGTH + 8
98 #define PLT_FDE_LEN_OFFSET 4 + PLT_CIE_LENGTH + 12
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 #define PLT_SFRAME_FDE_START_OFFSET sizeof (sframe_header)
105 #define ABI_64_P(abfd) \
106 (get_elf_backend_data (abfd)->s->elfclass == ELFCLASS64)
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 #define ELIMINATE_COPY_RELOCS 1
114 #define elf_x86_hash_table(p, id) \
115 (is_elf_hash_table ((p)->hash) \
116 && elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) == (id) \
117 ? ((struct elf_x86_link_hash_table *) ((p)->hash)) : NULL)
119 /* Will references to this symbol always be local in this object? */
120 #define SYMBOL_REFERENCES_LOCAL_P(INFO, H) \
121 _bfd_x86_elf_link_symbol_references_local ((INFO), (H))
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 ((EH)->elf.root.type == bfd_link_hash_undefweak \
129 && (SYMBOL_REFERENCES_LOCAL_P ((INFO), &(EH)->elf) \
130 || (bfd_link_executable (INFO) \
131 && (EH)->zero_undefweak > 0)))
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 ((EH)->def_protected \
138 && ((EH)->elf.root.type == bfd_link_hash_defined \
139 || (EH)->elf.root.type == bfd_link_hash_defweak) \
140 && ((EH)->elf.root.u.def.section->owner->flags & DYNAMIC) != 0 \
141 && ((EH)->elf.root.u.def.section->flags & SEC_CODE) == 0)
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).
151 If PCREL_PLT is true, don't generate dynamic relocation in PIE for
152 PC-relative relocation against a dynamic function definition in data
153 section when PLT address can be used.
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.
159 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 ((bfd_link_pic (INFO) \
164 && (! X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
165 || ((H) != NULL \
166 && (! (bfd_link_pie (INFO) \
167 || SYMBOLIC_BIND ((INFO), (H))) \
168 || (H)->root.type == bfd_link_hash_defweak \
169 || (!(bfd_link_pie (INFO) \
170 && (PCREL_PLT) \
171 && (H)->plt.refcount > 0 \
172 && ((SEC)->flags & SEC_CODE) == 0 \
173 && (H)->type == STT_FUNC \
174 && (H)->def_dynamic) \
175 && !(H)->def_regular))))) \
176 || ((H) != NULL \
177 && (H)->type == STT_GNU_IFUNC \
178 && (R_TYPE) == POINTER_TYPE \
179 && ((SEC)->flags & SEC_CODE) == 0) \
180 || (ELIMINATE_COPY_RELOCS \
181 && !bfd_link_pic (INFO) \
182 && (H) != NULL \
183 && ((H)->root.type == bfd_link_hash_defweak \
184 || !(H)->def_regular)))
186 /* TRUE if dynamic relocation should be generated. Don't copy a
187 pc-relative relocation into the output file if the symbol needs
188 copy reloc or the symbol is undefined when building executable.
189 Copy dynamic function pointer relocations. Don't generate dynamic
190 relocations against resolved undefined weak symbols in PIE, except
191 when PC32_RELOC is TRUE. Undefined weak symbol is bound locally
192 when PIC is false. Don't generate dynamic relocations against
193 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
196 absolute to section-relative in set_sym_sections called from
197 ldexp_finalize_syms after ldemul_finish. */
198 #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) \
201 ((bfd_link_pic (INFO) \
202 && !(bfd_is_abs_section (SEC) \
203 && ((EH) == NULL \
204 || (EH)->elf.root.rel_from_abs == 0) \
205 && ((EH) == NULL \
206 || SYMBOL_REFERENCES_LOCAL (INFO, &(EH)->elf))) \
207 && !(NEED_COPY_RELOC_IN_PIE) \
208 && ((EH) == NULL \
209 || ((ELF_ST_VISIBILITY ((EH)->elf.other) == STV_DEFAULT \
210 && (!(RESOLVED_TO_ZERO) || PC32_RELOC)) \
211 || (EH)->elf.root.type != bfd_link_hash_undefweak)) \
212 && ((!X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
213 && !X86_SIZE_TYPE_P (IS_X86_64, R_TYPE)) \
214 || ! SYMBOL_CALLS_LOCAL ((INFO), \
215 (struct elf_link_hash_entry *) (EH)))) \
216 || (ELIMINATE_COPY_RELOCS \
217 && !bfd_link_pic (INFO) \
218 && (EH) != NULL \
219 && (EH)->elf.dynindx != -1 \
220 && (!(EH)->elf.non_got_ref \
221 || ((EH)->elf.root.type == bfd_link_hash_undefweak \
222 && !(RESOLVED_TO_ZERO))) \
223 && (((EH)->elf.def_dynamic && !(EH)->elf.def_regular) \
224 || (EH)->elf.root.type == bfd_link_hash_undefined)))
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 ((H) != NULL \
230 && (H)->dynindx != -1 \
231 && (X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
232 || !(bfd_link_executable (INFO) || SYMBOLIC_BIND ((INFO), (H))) \
233 || !(H)->def_regular))
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 (!WILL_CALL_FINISH_DYNAMIC_SYMBOL ((HTAB)->elf.dynamic_sections_created, \
240 bfd_link_pic (INFO), (H)) \
241 || (bfd_link_pic (INFO) \
242 && SYMBOL_REFERENCES_LOCAL_P ((INFO), (H))) \
243 || (ELF_ST_VISIBILITY ((H)->other) \
244 && (H)->root.type == bfd_link_hash_undefweak))
246 /* TRUE if this symbol isn't defined by a shared object. */
247 #define SYMBOL_DEFINED_NON_SHARED_P(H) \
248 ((H)->def_regular \
249 || (H)->root.linker_def \
250 || (H)->root.ldscript_def \
251 || ((struct elf_x86_link_hash_entry *) (H))->linker_def \
252 || ELF_COMMON_DEF_P (H))
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 (bfd_is_abs_symbol (&(H)->root) && !(H)->root.ldscript_def)
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 ((H)->dynindx == -1 \
269 && !(H)->forced_local \
270 && (H)->root.type != bfd_link_hash_undefweak \
271 && bfd_link_pic (INFO) \
272 && !ABS_SYMBOL_P (H))
274 /* TRUE if this is a pointer reference to a local IFUNC. */
275 #define POINTER_LOCAL_IFUNC_P(INFO, H) \
276 ((H)->dynindx == -1 \
277 || (H)->forced_local \
278 || bfd_link_executable (INFO))
280 /* TRUE if this is a PLT reference to a local IFUNC. */
281 #define PLT_LOCAL_IFUNC_P(INFO, H) \
282 ((H)->dynindx == -1 \
283 || ((bfd_link_executable (INFO) \
284 || ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT) \
285 && (H)->def_regular \
286 && (H)->type == STT_GNU_IFUNC))
288 /* TRUE if TLS IE->LE transition is OK. */
289 #define TLS_TRANSITION_IE_TO_LE_P(INFO, H, TLS_TYPE) \
290 (bfd_link_executable (INFO) \
291 && (H) != NULL \
292 && (H)->dynindx == -1 \
293 && (TLS_TYPE & GOT_TLS_IE))
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 do \
299 if (((H)->dynindx == -1 \
300 && !LOCAL_UNDEFWEAK \
301 && !(((H)->forced_local || bfd_link_executable (INFO)) \
302 && (H)->def_regular \
303 && (H)->type == STT_GNU_IFUNC)) \
304 || (PLT) == NULL \
305 || (GOTPLT) == NULL \
306 || (RELPLT) == NULL) \
307 abort (); \
309 while (0);
311 /* Verify that the symbol supports copy relocation. */
312 #define VERIFY_COPY_RELOC(H, HTAB) \
313 do \
315 if ((H)->dynindx == -1 \
316 || ((H)->root.type != bfd_link_hash_defined \
317 && (H)->root.type != bfd_link_hash_defweak) \
318 || (HTAB)->elf.srelbss == NULL \
319 || (HTAB)->elf.sreldynrelro == NULL) \
320 abort (); \
322 while (0);
324 /* x86 ELF linker hash entry. */
326 struct elf_x86_link_hash_entry
328 struct elf_link_hash_entry elf;
330 unsigned char tls_type;
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;
338 /* Don't call finish_dynamic_symbol on this symbol. */
339 unsigned int no_finish_dynamic_symbol : 1;
341 /* R_*_RELATIVE relocation in GOT for this symbol has been
342 processed. */
343 unsigned int got_relative_reloc_done : 1;
345 /* TRUE if symbol is __tls_get_addr. */
346 unsigned int tls_get_addr : 1;
348 /* TRUE if symbol is defined as a protected symbol. */
349 unsigned int def_protected : 1;
351 /* 0: Symbol references are unknown.
352 1: Symbol references aren't local.
353 2: Symbol references are local.
355 unsigned int local_ref : 2;
357 /* TRUE if symbol is defined by linker. */
358 unsigned int linker_def : 1;
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;
364 /* TRUE if symbol is referenced by R_386_GOTOFF relocation. This is
365 only used by i386. */
366 unsigned int gotoff_ref : 1;
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;
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;
380 /* Information about the second PLT entry. */
381 union gotplt_union plt_second;
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;
388 #define SFRAME_PLT0_MAX_NUM_FRES 2
389 #define SFRAME_PLTN_MAX_NUM_FRES 2
391 struct elf_x86_sframe_plt
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];
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];
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];
406 struct elf_x86_lazy_plt_layout
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. */
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. */
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. */
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;
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;
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;
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;
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. */
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;
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;
454 /* Offset into plt_entry where the initial value of the GOT entry
455 points. */
456 unsigned int plt_lazy_offset;
458 /* The first entry in a PIC lazy procedure linkage table looks like
459 this. */
460 const bfd_byte *pic_plt0_entry;
462 /* Subsequent entries in a PIC lazy procedure linkage table look
463 like this. */
464 const bfd_byte *pic_plt_entry;
466 /* .eh_frame covering the lazy .plt section. */
467 const bfd_byte *eh_frame_plt;
468 unsigned int eh_frame_plt_size;
471 struct elf_x86_non_lazy_plt_layout
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;
480 unsigned int plt_entry_size; /* Size of each PLT entry. */
482 /* Offsets into plt_entry that are to be replaced with... */
483 unsigned int plt_got_offset; /* ... address of this symbol in .got. */
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;
489 /* .eh_frame covering the non-lazy .plt section. */
490 const bfd_byte *eh_frame_plt;
491 unsigned int eh_frame_plt_size;
494 struct elf_x86_plt_layout
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. */
502 /* 1 has PLT0. */
503 unsigned int has_plt0;
505 /* Offsets into plt_entry that are to be replaced with... */
506 unsigned int plt_got_offset; /* ... address of this symbol in .got. */
508 /* Length of the PC-relative instruction containing plt_got_offset.
509 This is only used for x86-64. */
510 unsigned int plt_got_insn_size;
512 /* Alignment of the .iplt section. */
513 unsigned int iplt_alignment;
515 /* .eh_frame covering the .plt section. */
516 const bfd_byte *eh_frame_plt;
517 unsigned int eh_frame_plt_size;
520 /* Values in tls_type of x86 ELF linker hash entry. */
521 #define GOT_UNKNOWN 0
522 #define GOT_NORMAL 1
523 #define GOT_TLS_GD 2
524 #define GOT_TLS_IE 4
525 #define GOT_TLS_IE_POS 5
526 #define GOT_TLS_IE_NEG 6
527 #define GOT_TLS_IE_BOTH 7
528 #define GOT_TLS_GDESC 8
529 #define GOT_ABS 9
530 #define GOT_TLS_GD_BOTH_P(type) \
531 ((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
532 #define GOT_TLS_GD_P(type) \
533 ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
534 #define GOT_TLS_GDESC_P(type) \
535 ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
536 #define GOT_TLS_GD_ANY_P(type) \
537 (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
539 #define elf_x86_hash_entry(ent) \
540 ((struct elf_x86_link_hash_entry *)(ent))
542 /* Information of an input relocation used to compute its contribution
543 to the DT_RELR section size. */
545 struct elf_x86_relative_reloc_record
547 /* The original relocation info. */
548 Elf_Internal_Rela rel;
549 /* The input or the GOT section where the relocation is applied. */
550 asection *sec;
551 /* Local symbol info. NULL for global symbol. */
552 Elf_Internal_Sym *sym;
553 union
555 /* Section where the local symbol is defined. */
556 asection *sym_sec;
557 /* Global symbol hash. */
558 struct elf_link_hash_entry *h;
559 } u;
560 /* The offset into the output section where the relative relocation
561 will be applied at run-time. */
562 bfd_vma offset;
563 /* The run-time address. */
564 bfd_vma address;
567 struct elf_x86_relative_reloc_data
569 bfd_size_type count;
570 bfd_size_type size;
571 struct elf_x86_relative_reloc_record *data;
574 /* DT_RELR bitmap. */
575 struct elf_dt_relr_bitmap
577 bfd_size_type count;
578 bfd_size_type size;
579 union
581 /* 32-bit bitmap. */
582 uint32_t *elf32;
583 /* 64-bit bitmap. */
584 uint64_t *elf64;
585 } u;
588 /* x86 ELF linker hash table. */
590 struct elf_x86_link_hash_table
592 struct elf_link_hash_table elf;
594 /* Short-cuts to get to dynamic linker sections. */
595 asection *interp;
596 asection *plt_eh_frame;
597 asection *plt_second;
598 asection *plt_second_eh_frame;
599 asection *plt_got;
600 asection *plt_got_eh_frame;
602 sframe_encoder_ctx *plt_cfe_ctx;
603 asection *plt_sframe;
604 sframe_encoder_ctx *plt_second_cfe_ctx;
605 asection *plt_second_sframe;
607 /* Parameters describing PLT generation, lazy or non-lazy. */
608 struct elf_x86_plt_layout plt;
610 /* Parameters describing lazy PLT generation. */
611 const struct elf_x86_lazy_plt_layout *lazy_plt;
613 /* Parameters describing non-lazy PLT generation. */
614 const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
616 /* The .sframe helper object for .plt section.
617 This is used for x86-64 only. */
618 const struct elf_x86_sframe_plt *sframe_plt;
620 union
622 bfd_signed_vma refcount;
623 bfd_vma offset;
624 } tls_ld_or_ldm_got;
626 /* The amount of space used by the jump slots in the GOT. */
627 bfd_vma sgotplt_jump_table_size;
629 /* _TLS_MODULE_BASE_ symbol. */
630 struct bfd_link_hash_entry *tls_module_base;
632 /* Used by local STT_GNU_IFUNC symbols. */
633 htab_t loc_hash_table;
634 void * loc_hash_memory;
636 /* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt. */
637 bfd_vma next_jump_slot_index;
638 /* The index of the next R_X86_64_IRELATIVE entry in .rela.plt. */
639 bfd_vma next_irelative_index;
641 /* The (unloaded but important) .rel.plt.unloaded section on VxWorks.
642 This is used for i386 only. */
643 asection *srelplt2;
645 /* The index of the next unused R_386_TLS_DESC slot in .rel.plt. This
646 is only used for i386. */
647 bfd_vma next_tls_desc_index;
649 /* DT_RELR bitmap. */
650 struct elf_dt_relr_bitmap dt_relr_bitmap;
652 /* Relative relocation data. */
653 struct elf_x86_relative_reloc_data relative_reloc;
655 /* Unaligned relative relocation data. */
656 struct elf_x86_relative_reloc_data unaligned_relative_reloc;
658 /* Number of relative reloc generation pass. */
659 unsigned int generate_relative_reloc_pass;
661 /* Value used to fill the unused bytes of the first PLT entry. This
662 is only used for i386. */
663 bfd_byte plt0_pad_byte;
665 /* TRUE if GOT is referenced. */
666 unsigned int got_referenced : 1;
668 /* TRUE if PLT is PC-relative. PLT in PDE and PC-relative PLT in PIE
669 can be used as function address.
671 NB: i386 has non-PIC PLT and PIC PLT. Only non-PIC PLT in PDE can
672 be used as function address. PIC PLT in PIE can't be used as
673 function address. */
674 unsigned int pcrel_plt : 1;
676 bfd_vma (*r_info) (bfd_vma, bfd_vma);
677 bfd_vma (*r_sym) (bfd_vma);
678 bool (*is_reloc_section) (const char *);
679 unsigned int sizeof_reloc;
680 unsigned int got_entry_size;
681 unsigned int pointer_r_type;
682 unsigned int relative_r_type;
683 int dynamic_interpreter_size;
684 const char *dynamic_interpreter;
685 const char *tls_get_addr;
686 const char *relative_r_name;
687 void (*elf_append_reloc) (bfd *, asection *, Elf_Internal_Rela *);
688 void (*elf_write_addend) (bfd *, uint64_t, void *);
689 void (*elf_write_addend_in_got) (bfd *, uint64_t, void *);
691 /* Options passed from the linker. */
692 struct elf_linker_x86_params *params;
695 struct elf_x86_init_table
697 /* The lazy PLT layout. */
698 const struct elf_x86_lazy_plt_layout *lazy_plt;
700 /* The non-lazy PLT layout. */
701 const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
703 /* The lazy PLT layout for IBT. */
704 const struct elf_x86_lazy_plt_layout *lazy_ibt_plt;
706 /* The non-lazy PLT layout for IBT. */
707 const struct elf_x86_non_lazy_plt_layout *non_lazy_ibt_plt;
709 /* The .sframe helper object for lazy .plt section.
710 This is used for x86-64 only. */
711 const struct elf_x86_sframe_plt *sframe_lazy_plt;
713 /* The .sframe helper object for non-lazy .plt section.
714 This is used for x86-64 only. */
715 const struct elf_x86_sframe_plt *sframe_non_lazy_plt;
717 /* The .sframe helper object for lazy IBT .plt section.
718 This is used for x86-64 only. */
719 const struct elf_x86_sframe_plt *sframe_lazy_ibt_plt;
721 /* The .sframe helper object for non-lazy IBT .plt section.
722 This is used for x86-64 only. */
723 const struct elf_x86_sframe_plt *sframe_non_lazy_ibt_plt;
725 bfd_byte plt0_pad_byte;
727 bfd_vma (*r_info) (bfd_vma, bfd_vma);
728 bfd_vma (*r_sym) (bfd_vma);
731 struct elf_x86_obj_tdata
733 struct elf_obj_tdata root;
735 /* tls_type for each local got entry. */
736 char *local_got_tls_type;
738 /* GOTPLT entries for TLS descriptors. */
739 bfd_vma *local_tlsdesc_gotent;
741 /* R_*_RELATIVE relocation in GOT for this local symbol has been
742 processed. */
743 char *relative_reloc_done;
746 enum elf_x86_plt_type
748 plt_non_lazy = 0,
749 plt_lazy = 1 << 0,
750 plt_pic = 1 << 1,
751 plt_second = 1 << 2,
752 plt_unknown = -1
755 struct elf_x86_plt
757 const char *name;
758 asection *sec;
759 bfd_byte *contents;
760 enum elf_x86_plt_type type;
761 unsigned int plt_got_offset;
762 unsigned int plt_entry_size;
763 unsigned int plt_got_insn_size; /* Only used for x86-64. */
764 long count;
767 /* Set if a relocation is converted from a GOTPCREL relocation. */
768 #define R_X86_64_converted_reloc_bit (1 << 7)
770 #define elf_x86_tdata(abfd) \
771 ((struct elf_x86_obj_tdata *) (abfd)->tdata.any)
773 #define elf_x86_local_got_tls_type(abfd) \
774 (elf_x86_tdata (abfd)->local_got_tls_type)
776 #define elf_x86_local_tlsdesc_gotent(abfd) \
777 (elf_x86_tdata (abfd)->local_tlsdesc_gotent)
779 #define elf_x86_relative_reloc_done(abfd) \
780 (elf_x86_tdata (abfd)->relative_reloc_done)
782 #define elf_x86_compute_jump_table_size(htab) \
783 ((htab)->elf.srelplt->reloc_count * (htab)->got_entry_size)
785 #define is_x86_elf(bfd, htab) \
786 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \
787 && elf_tdata (bfd) != NULL \
788 && elf_object_id (bfd) == (htab)->elf.hash_table_id)
790 /* Rename some of the generic section flags to better document how they
791 are used here. */
792 #define check_relocs_failed sec_flg0
793 #define relative_reloc_packed sec_flg1
795 extern bool _bfd_x86_elf_mkobject
796 (bfd *);
798 extern void _bfd_x86_elf_set_tls_module_base
799 (struct bfd_link_info *);
801 extern bfd_vma _bfd_x86_elf_dtpoff_base
802 (struct bfd_link_info *);
804 extern bool _bfd_x86_elf_readonly_dynrelocs
805 (struct elf_link_hash_entry *, void *);
807 extern struct elf_link_hash_entry * _bfd_elf_x86_get_local_sym_hash
808 (struct elf_x86_link_hash_table *, bfd *, const Elf_Internal_Rela *,
809 bool);
811 extern hashval_t _bfd_x86_elf_local_htab_hash
812 (const void *);
814 extern int _bfd_x86_elf_local_htab_eq
815 (const void *, const void *);
817 extern struct bfd_hash_entry * _bfd_x86_elf_link_hash_newfunc
818 (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
820 extern struct bfd_link_hash_table * _bfd_x86_elf_link_hash_table_create
821 (bfd *);
823 extern int _bfd_x86_elf_compare_relocs
824 (const void *, const void *);
826 extern bool _bfd_x86_elf_link_check_relocs
827 (bfd *, struct bfd_link_info *);
829 extern bool _bfd_x86_elf_check_relocs
830 (bfd *, struct bfd_link_info *, asection *,
831 const Elf_Internal_Rela *);
833 extern bool _bfd_x86_elf_link_relax_section
834 (bfd *, asection *, struct bfd_link_info *, bool *);
836 extern bool _bfd_elf_x86_size_relative_relocs
837 (struct bfd_link_info *, bool *);
839 extern bool _bfd_elf_x86_finish_relative_relocs
840 (struct bfd_link_info *);
842 extern void _bfd_elf32_write_addend (bfd *, uint64_t, void *);
843 extern void _bfd_elf64_write_addend (bfd *, uint64_t, void *);
845 extern bool _bfd_elf_x86_valid_reloc_p
846 (asection *, struct bfd_link_info *, struct elf_x86_link_hash_table *,
847 const Elf_Internal_Rela *, struct elf_link_hash_entry *,
848 Elf_Internal_Sym *, Elf_Internal_Shdr *, bool *);
850 extern bool _bfd_x86_elf_size_dynamic_sections
851 (bfd *, struct bfd_link_info *);
853 extern struct elf_x86_link_hash_table *_bfd_x86_elf_finish_dynamic_sections
854 (bfd *, struct bfd_link_info *);
856 extern bool _bfd_x86_elf_always_size_sections
857 (bfd *, struct bfd_link_info *);
859 extern void _bfd_x86_elf_merge_symbol_attribute
860 (struct elf_link_hash_entry *, unsigned int, bool, bool);
862 extern void _bfd_x86_elf_copy_indirect_symbol
863 (struct bfd_link_info *, struct elf_link_hash_entry *,
864 struct elf_link_hash_entry *);
866 extern bool _bfd_x86_elf_fixup_symbol
867 (struct bfd_link_info *, struct elf_link_hash_entry *);
869 extern bool _bfd_x86_elf_hash_symbol
870 (struct elf_link_hash_entry *);
872 extern bool _bfd_x86_elf_adjust_dynamic_symbol
873 (struct bfd_link_info *, struct elf_link_hash_entry *);
875 extern void _bfd_x86_elf_hide_symbol
876 (struct bfd_link_info *, struct elf_link_hash_entry *, bool);
878 extern bool _bfd_x86_elf_link_symbol_references_local
879 (struct bfd_link_info *, struct elf_link_hash_entry *);
881 extern asection * _bfd_x86_elf_gc_mark_hook
882 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
883 struct elf_link_hash_entry *, Elf_Internal_Sym *);
885 extern long _bfd_x86_elf_get_synthetic_symtab
886 (bfd *, long, long, bfd_vma, struct elf_x86_plt [], asymbol **,
887 asymbol **);
889 extern enum elf_property_kind _bfd_x86_elf_parse_gnu_properties
890 (bfd *, unsigned int, bfd_byte *, unsigned int);
892 extern bool _bfd_x86_elf_merge_gnu_properties
893 (struct bfd_link_info *, bfd *, bfd *, elf_property *, elf_property *);
895 extern void _bfd_x86_elf_link_fixup_gnu_properties
896 (struct bfd_link_info *, elf_property_list **);
898 extern bfd * _bfd_x86_elf_link_setup_gnu_properties
899 (struct bfd_link_info *, struct elf_x86_init_table *);
901 extern void _bfd_x86_elf_link_fixup_ifunc_symbol
902 (struct bfd_link_info *, struct elf_x86_link_hash_table *,
903 struct elf_link_hash_entry *, Elf_Internal_Sym *sym);
905 extern void _bfd_x86_elf_link_report_relative_reloc
906 (struct bfd_link_info *, asection *, struct elf_link_hash_entry *,
907 Elf_Internal_Sym *, const char *, const void *);
909 #define bfd_elf64_mkobject \
910 _bfd_x86_elf_mkobject
911 #define bfd_elf32_mkobject \
912 _bfd_x86_elf_mkobject
913 #define bfd_elf64_bfd_link_hash_table_create \
914 _bfd_x86_elf_link_hash_table_create
915 #define bfd_elf32_bfd_link_hash_table_create \
916 _bfd_x86_elf_link_hash_table_create
917 #define bfd_elf64_bfd_link_check_relocs \
918 _bfd_x86_elf_link_check_relocs
919 #define bfd_elf32_bfd_link_check_relocs \
920 _bfd_x86_elf_link_check_relocs
921 #define bfd_elf32_bfd_relax_section \
922 _bfd_x86_elf_link_relax_section
923 #define bfd_elf64_bfd_relax_section \
924 _bfd_x86_elf_link_relax_section
926 #define elf_backend_check_relocs \
927 _bfd_x86_elf_check_relocs
928 #define elf_backend_size_dynamic_sections \
929 _bfd_x86_elf_size_dynamic_sections
930 #define elf_backend_merge_symbol_attribute \
931 _bfd_x86_elf_merge_symbol_attribute
932 #define elf_backend_copy_indirect_symbol \
933 _bfd_x86_elf_copy_indirect_symbol
934 #define elf_backend_fixup_symbol \
935 _bfd_x86_elf_fixup_symbol
936 #define elf_backend_hash_symbol \
937 _bfd_x86_elf_hash_symbol
938 #define elf_backend_adjust_dynamic_symbol \
939 _bfd_x86_elf_adjust_dynamic_symbol
940 #define elf_backend_gc_mark_hook \
941 _bfd_x86_elf_gc_mark_hook
942 #define elf_backend_omit_section_dynsym \
943 _bfd_elf_omit_section_dynsym_all
944 #define elf_backend_parse_gnu_properties \
945 _bfd_x86_elf_parse_gnu_properties
946 #define elf_backend_merge_gnu_properties \
947 _bfd_x86_elf_merge_gnu_properties
948 #define elf_backend_fixup_gnu_properties \
949 _bfd_x86_elf_link_fixup_gnu_properties
950 #define elf_backend_size_relative_relocs \
951 _bfd_elf_x86_size_relative_relocs
952 #define elf_backend_finish_relative_relocs \
953 _bfd_elf_x86_finish_relative_relocs
955 #define ELF_P_ALIGN ELF_MINPAGESIZE
957 /* Allocate x86 GOT info for local symbols. */
959 static inline bool
960 elf_x86_allocate_local_got_info (bfd *abfd, bfd_size_type count)
962 bfd_signed_vma *local_got_refcounts = elf_local_got_refcounts (abfd);
963 if (local_got_refcounts == NULL)
965 bfd_size_type size = count * (sizeof (bfd_signed_vma)
966 + sizeof (bfd_vma)
967 + 2 * sizeof(char));
968 local_got_refcounts = (bfd_signed_vma *) bfd_zalloc (abfd, size);
969 if (local_got_refcounts == NULL)
970 return false;
971 elf_local_got_refcounts (abfd) = local_got_refcounts;
972 elf_x86_local_tlsdesc_gotent (abfd) =
973 (bfd_vma *) (local_got_refcounts + count);
974 elf_x86_local_got_tls_type (abfd) =
975 (char *) (local_got_refcounts + 2 * count);
976 elf_x86_relative_reloc_done (abfd) =
977 ((char *) (local_got_refcounts + 2 * count)) + count;
979 return true;