* elflink.h (elf_gc_mark): Pass in the section whose relocs we are
[deliverable/binutils-gdb.git] / bfd / elf64-x86-64.c
1 /* X86-64 specific support for 64-bit ELF
2 Copyright 2000, 2001, 2002 Free Software Foundation, Inc.
3 Contributed by Jan Hubicka <jh@suse.cz>.
4
5 This file is part of BFD, the Binary File Descriptor library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20
21 #include "bfd.h"
22 #include "sysdep.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #include "elf-bfd.h"
26
27 #include "elf/x86-64.h"
28
29 /* We use only the RELA entries. */
30 #define USE_RELA 1
31
32 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
33 #define MINUS_ONE (~ (bfd_vma) 0)
34
35 /* The relocation "howto" table. Order of fields:
36 type, size, bitsize, pc_relative, complain_on_overflow,
37 special_function, name, partial_inplace, src_mask, dst_pack, pcrel_offset. */
38 static reloc_howto_type x86_64_elf_howto_table[] =
39 {
40 HOWTO(R_X86_64_NONE, 0, 0, 0, false, 0, complain_overflow_dont,
41 bfd_elf_generic_reloc, "R_X86_64_NONE", false, 0x00000000, 0x00000000,
42 false),
43 HOWTO(R_X86_64_64, 0, 4, 64, false, 0, complain_overflow_bitfield,
44 bfd_elf_generic_reloc, "R_X86_64_64", false, MINUS_ONE, MINUS_ONE,
45 false),
46 HOWTO(R_X86_64_PC32, 0, 4, 32, true, 0, complain_overflow_signed,
47 bfd_elf_generic_reloc, "R_X86_64_PC32", false, 0xffffffff, 0xffffffff,
48 true),
49 HOWTO(R_X86_64_GOT32, 0, 4, 32, false, 0, complain_overflow_signed,
50 bfd_elf_generic_reloc, "R_X86_64_GOT32", false, 0xffffffff, 0xffffffff,
51 false),
52 HOWTO(R_X86_64_PLT32, 0, 4, 32, true, 0, complain_overflow_signed,
53 bfd_elf_generic_reloc, "R_X86_64_PLT32", false, 0xffffffff, 0xffffffff,
54 true),
55 HOWTO(R_X86_64_COPY, 0, 4, 32, false, 0, complain_overflow_bitfield,
56 bfd_elf_generic_reloc, "R_X86_64_COPY", false, 0xffffffff, 0xffffffff,
57 false),
58 HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, false, 0, complain_overflow_bitfield,
59 bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", false, MINUS_ONE,
60 MINUS_ONE, false),
61 HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, false, 0, complain_overflow_bitfield,
62 bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", false, MINUS_ONE,
63 MINUS_ONE, false),
64 HOWTO(R_X86_64_RELATIVE, 0, 4, 64, false, 0, complain_overflow_bitfield,
65 bfd_elf_generic_reloc, "R_X86_64_RELATIVE", false, MINUS_ONE,
66 MINUS_ONE, false),
67 HOWTO(R_X86_64_GOTPCREL, 0, 4, 32, true,0 , complain_overflow_signed,
68 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", false, 0xffffffff,
69 0xffffffff, true),
70 HOWTO(R_X86_64_32, 0, 4, 32, false, 0, complain_overflow_unsigned,
71 bfd_elf_generic_reloc, "R_X86_64_32", false, 0xffffffff, 0xffffffff,
72 false),
73 HOWTO(R_X86_64_32S, 0, 4, 32, false, 0, complain_overflow_signed,
74 bfd_elf_generic_reloc, "R_X86_64_32S", false, 0xffffffff, 0xffffffff,
75 false),
76 HOWTO(R_X86_64_16, 0, 1, 16, false, 0, complain_overflow_bitfield,
77 bfd_elf_generic_reloc, "R_X86_64_16", false, 0xffff, 0xffff, false),
78 HOWTO(R_X86_64_PC16,0, 1, 16, true, 0, complain_overflow_bitfield,
79 bfd_elf_generic_reloc, "R_X86_64_PC16", false, 0xffff, 0xffff, true),
80 HOWTO(R_X86_64_8, 0, 0, 8, false, 0, complain_overflow_signed,
81 bfd_elf_generic_reloc, "R_X86_64_8", false, 0xff, 0xff, false),
82 HOWTO(R_X86_64_PC8, 0, 0, 8, true, 0, complain_overflow_signed,
83 bfd_elf_generic_reloc, "R_X86_64_PC8", false, 0xff, 0xff, true),
84
85 /* GNU extension to record C++ vtable hierarchy. */
86 HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, false, 0, complain_overflow_dont,
87 NULL, "R_X86_64_GNU_VTINHERIT", false, 0, 0, false),
88
89 /* GNU extension to record C++ vtable member usage. */
90 HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, false, 0, complain_overflow_dont,
91 _bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", false, 0, 0,
92 false)
93 };
94
95 /* Map BFD relocs to the x86_64 elf relocs. */
96 struct elf_reloc_map
97 {
98 bfd_reloc_code_real_type bfd_reloc_val;
99 unsigned char elf_reloc_val;
100 };
101
102 static const struct elf_reloc_map x86_64_reloc_map[] =
103 {
104 { BFD_RELOC_NONE, R_X86_64_NONE, },
105 { BFD_RELOC_64, R_X86_64_64, },
106 { BFD_RELOC_32_PCREL, R_X86_64_PC32, },
107 { BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,},
108 { BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,},
109 { BFD_RELOC_X86_64_COPY, R_X86_64_COPY, },
110 { BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, },
111 { BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, },
112 { BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, },
113 { BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, },
114 { BFD_RELOC_32, R_X86_64_32, },
115 { BFD_RELOC_X86_64_32S, R_X86_64_32S, },
116 { BFD_RELOC_16, R_X86_64_16, },
117 { BFD_RELOC_16_PCREL, R_X86_64_PC16, },
118 { BFD_RELOC_8, R_X86_64_8, },
119 { BFD_RELOC_8_PCREL, R_X86_64_PC8, },
120 { BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
121 { BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
122 };
123
124 static reloc_howto_type *elf64_x86_64_reloc_type_lookup
125 PARAMS ((bfd *, bfd_reloc_code_real_type));
126 static void elf64_x86_64_info_to_howto
127 PARAMS ((bfd *, arelent *, Elf64_Internal_Rela *));
128 static boolean elf64_x86_64_grok_prstatus
129 PARAMS ((bfd *, Elf_Internal_Note *));
130 static boolean elf64_x86_64_grok_psinfo
131 PARAMS ((bfd *, Elf_Internal_Note *));
132 static struct bfd_link_hash_table *elf64_x86_64_link_hash_table_create
133 PARAMS ((bfd *));
134 static boolean elf64_x86_64_elf_object_p PARAMS ((bfd *abfd));
135 static boolean create_got_section
136 PARAMS((bfd *, struct bfd_link_info *));
137 static boolean elf64_x86_64_create_dynamic_sections
138 PARAMS((bfd *, struct bfd_link_info *));
139 static void elf64_x86_64_copy_indirect_symbol
140 PARAMS ((struct elf_link_hash_entry *, struct elf_link_hash_entry *));
141 static boolean elf64_x86_64_check_relocs
142 PARAMS ((bfd *, struct bfd_link_info *, asection *sec,
143 const Elf_Internal_Rela *));
144 static asection *elf64_x86_64_gc_mark_hook
145 PARAMS ((asection *, struct bfd_link_info *, Elf_Internal_Rela *,
146 struct elf_link_hash_entry *, Elf_Internal_Sym *));
147
148 static boolean elf64_x86_64_gc_sweep_hook
149 PARAMS ((bfd *, struct bfd_link_info *, asection *,
150 const Elf_Internal_Rela *));
151
152 static struct bfd_hash_entry *link_hash_newfunc
153 PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
154 static boolean elf64_x86_64_adjust_dynamic_symbol
155 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
156
157 static boolean allocate_dynrelocs
158 PARAMS ((struct elf_link_hash_entry *, PTR));
159 static boolean readonly_dynrelocs
160 PARAMS ((struct elf_link_hash_entry *, PTR));
161 static boolean elf64_x86_64_size_dynamic_sections
162 PARAMS ((bfd *, struct bfd_link_info *));
163 static boolean elf64_x86_64_relocate_section
164 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
165 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
166 static boolean elf64_x86_64_finish_dynamic_symbol
167 PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
168 Elf_Internal_Sym *sym));
169 static boolean elf64_x86_64_finish_dynamic_sections
170 PARAMS ((bfd *, struct bfd_link_info *));
171 static enum elf_reloc_type_class elf64_x86_64_reloc_type_class
172 PARAMS ((const Elf_Internal_Rela *));
173
174 /* Given a BFD reloc type, return a HOWTO structure. */
175 static reloc_howto_type *
176 elf64_x86_64_reloc_type_lookup (abfd, code)
177 bfd *abfd ATTRIBUTE_UNUSED;
178 bfd_reloc_code_real_type code;
179 {
180 unsigned int i;
181 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
182 i++)
183 {
184 if (x86_64_reloc_map[i].bfd_reloc_val == code)
185 return &x86_64_elf_howto_table[i];
186 }
187 return 0;
188 }
189
190 /* Given an x86_64 ELF reloc type, fill in an arelent structure. */
191
192 static void
193 elf64_x86_64_info_to_howto (abfd, cache_ptr, dst)
194 bfd *abfd ATTRIBUTE_UNUSED;
195 arelent *cache_ptr;
196 Elf64_Internal_Rela *dst;
197 {
198 unsigned r_type, i;
199
200 r_type = ELF64_R_TYPE (dst->r_info);
201 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT)
202 {
203 BFD_ASSERT (r_type <= (unsigned int) R_X86_64_PC8);
204 i = r_type;
205 }
206 else
207 {
208 BFD_ASSERT (r_type < (unsigned int) R_X86_64_max);
209 i = r_type - ((unsigned int) R_X86_64_GNU_VTINHERIT - R_X86_64_PC8 - 1);
210 }
211 cache_ptr->howto = &x86_64_elf_howto_table[i];
212 BFD_ASSERT (r_type == cache_ptr->howto->type);
213 }
214 \f
215 /* Support for core dump NOTE sections. */
216 static boolean
217 elf64_x86_64_grok_prstatus (abfd, note)
218 bfd *abfd;
219 Elf_Internal_Note *note;
220 {
221 int offset;
222 size_t raw_size;
223
224 switch (note->descsz)
225 {
226 default:
227 return false;
228
229 case 336: /* sizeof(istruct elf_prstatus) on Linux/x86_64 */
230 /* pr_cursig */
231 elf_tdata (abfd)->core_signal
232 = bfd_get_16 (abfd, note->descdata + 12);
233
234 /* pr_pid */
235 elf_tdata (abfd)->core_pid
236 = bfd_get_32 (abfd, note->descdata + 32);
237
238 /* pr_reg */
239 offset = 112;
240 raw_size = 216;
241
242 break;
243 }
244
245 /* Make a ".reg/999" section. */
246 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
247 raw_size, note->descpos + offset);
248 }
249
250 static boolean
251 elf64_x86_64_grok_psinfo (abfd, note)
252 bfd *abfd;
253 Elf_Internal_Note *note;
254 {
255 switch (note->descsz)
256 {
257 default:
258 return false;
259
260 case 136: /* sizeof(struct elf_prpsinfo) on Linux/x86_64 */
261 elf_tdata (abfd)->core_program
262 = _bfd_elfcore_strndup (abfd, note->descdata + 40, 16);
263 elf_tdata (abfd)->core_command
264 = _bfd_elfcore_strndup (abfd, note->descdata + 56, 80);
265 }
266
267 /* Note that for some reason, a spurious space is tacked
268 onto the end of the args in some (at least one anyway)
269 implementations, so strip it off if it exists. */
270
271 {
272 char *command = elf_tdata (abfd)->core_command;
273 int n = strlen (command);
274
275 if (0 < n && command[n - 1] == ' ')
276 command[n - 1] = '\0';
277 }
278
279 return true;
280 }
281 \f
282 /* Functions for the x86-64 ELF linker. */
283
284 /* The name of the dynamic interpreter. This is put in the .interp
285 section. */
286
287 #define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
288
289 /* The size in bytes of an entry in the global offset table. */
290
291 #define GOT_ENTRY_SIZE 8
292
293 /* The size in bytes of an entry in the procedure linkage table. */
294
295 #define PLT_ENTRY_SIZE 16
296
297 /* The first entry in a procedure linkage table looks like this. See the
298 SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
299
300 static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
301 {
302 0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
303 0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
304 0x90, 0x90, 0x90, 0x90 /* pad out to 16 bytes with nops. */
305 };
306
307 /* Subsequent entries in a procedure linkage table look like this. */
308
309 static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
310 {
311 0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
312 0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
313 0x68, /* pushq immediate */
314 0, 0, 0, 0, /* replaced with index into relocation table. */
315 0xe9, /* jmp relative */
316 0, 0, 0, 0 /* replaced with offset to start of .plt0. */
317 };
318
319 /* The x86-64 linker needs to keep track of the number of relocs that
320 it decides to copy as dynamic relocs in check_relocs for each symbol.
321 This is so that it can later discard them if they are found to be
322 unnecessary. We store the information in a field extending the
323 regular ELF linker hash table. */
324
325 struct elf64_x86_64_dyn_relocs
326 {
327 /* Next section. */
328 struct elf64_x86_64_dyn_relocs *next;
329
330 /* The input section of the reloc. */
331 asection *sec;
332
333 /* Total number of relocs copied for the input section. */
334 bfd_size_type count;
335
336 /* Number of pc-relative relocs copied for the input section. */
337 bfd_size_type pc_count;
338 };
339
340 /* x86-64 ELF linker hash entry. */
341
342 struct elf64_x86_64_link_hash_entry
343 {
344 struct elf_link_hash_entry elf;
345
346 /* Track dynamic relocs copied for this symbol. */
347 struct elf64_x86_64_dyn_relocs *dyn_relocs;
348 };
349
350 /* x86-64 ELF linker hash table. */
351
352 struct elf64_x86_64_link_hash_table
353 {
354 struct elf_link_hash_table elf;
355
356 /* Short-cuts to get to dynamic linker sections. */
357 asection *sgot;
358 asection *sgotplt;
359 asection *srelgot;
360 asection *splt;
361 asection *srelplt;
362 asection *sdynbss;
363 asection *srelbss;
364
365 /* Small local sym to section mapping cache. */
366 struct sym_sec_cache sym_sec;
367 };
368
369 /* Get the x86-64 ELF linker hash table from a link_info structure. */
370
371 #define elf64_x86_64_hash_table(p) \
372 ((struct elf64_x86_64_link_hash_table *) ((p)->hash))
373
374 /* Create an entry in an x86-64 ELF linker hash table. */
375
376 static struct bfd_hash_entry *
377 link_hash_newfunc (entry, table, string)
378 struct bfd_hash_entry *entry;
379 struct bfd_hash_table *table;
380 const char *string;
381 {
382 /* Allocate the structure if it has not already been allocated by a
383 subclass. */
384 if (entry == NULL)
385 {
386 entry = bfd_hash_allocate (table,
387 sizeof (struct elf64_x86_64_link_hash_entry));
388 if (entry == NULL)
389 return entry;
390 }
391
392 /* Call the allocation method of the superclass. */
393 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
394 if (entry != NULL)
395 {
396 struct elf64_x86_64_link_hash_entry *eh;
397
398 eh = (struct elf64_x86_64_link_hash_entry *) entry;
399 eh->dyn_relocs = NULL;
400 }
401
402 return entry;
403 }
404
405 /* Create an X86-64 ELF linker hash table. */
406
407 static struct bfd_link_hash_table *
408 elf64_x86_64_link_hash_table_create (abfd)
409 bfd *abfd;
410 {
411 struct elf64_x86_64_link_hash_table *ret;
412 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table);
413
414 ret = (struct elf64_x86_64_link_hash_table *) bfd_malloc (amt);
415 if (ret == NULL)
416 return NULL;
417
418 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc))
419 {
420 free (ret);
421 return NULL;
422 }
423
424 ret->sgot = NULL;
425 ret->sgotplt = NULL;
426 ret->srelgot = NULL;
427 ret->splt = NULL;
428 ret->srelplt = NULL;
429 ret->sdynbss = NULL;
430 ret->srelbss = NULL;
431 ret->sym_sec.abfd = NULL;
432
433 return &ret->elf.root;
434 }
435
436 /* Create .got, .gotplt, and .rela.got sections in DYNOBJ, and set up
437 shortcuts to them in our hash table. */
438
439 static boolean
440 create_got_section (dynobj, info)
441 bfd *dynobj;
442 struct bfd_link_info *info;
443 {
444 struct elf64_x86_64_link_hash_table *htab;
445
446 if (! _bfd_elf_create_got_section (dynobj, info))
447 return false;
448
449 htab = elf64_x86_64_hash_table (info);
450 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
451 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
452 if (!htab->sgot || !htab->sgotplt)
453 abort ();
454
455 htab->srelgot = bfd_make_section (dynobj, ".rela.got");
456 if (htab->srelgot == NULL
457 || ! bfd_set_section_flags (dynobj, htab->srelgot,
458 (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
459 | SEC_IN_MEMORY | SEC_LINKER_CREATED
460 | SEC_READONLY))
461 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 3))
462 return false;
463 return true;
464 }
465
466 /* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and
467 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our
468 hash table. */
469
470 static boolean
471 elf64_x86_64_create_dynamic_sections (dynobj, info)
472 bfd *dynobj;
473 struct bfd_link_info *info;
474 {
475 struct elf64_x86_64_link_hash_table *htab;
476
477 htab = elf64_x86_64_hash_table (info);
478 if (!htab->sgot && !create_got_section (dynobj, info))
479 return false;
480
481 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
482 return false;
483
484 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
485 htab->srelplt = bfd_get_section_by_name (dynobj, ".rela.plt");
486 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
487 if (!info->shared)
488 htab->srelbss = bfd_get_section_by_name (dynobj, ".rela.bss");
489
490 if (!htab->splt || !htab->srelplt || !htab->sdynbss
491 || (!info->shared && !htab->srelbss))
492 abort ();
493
494 return true;
495 }
496
497 /* Copy the extra info we tack onto an elf_link_hash_entry. */
498
499 static void
500 elf64_x86_64_copy_indirect_symbol (dir, ind)
501 struct elf_link_hash_entry *dir, *ind;
502 {
503 struct elf64_x86_64_link_hash_entry *edir, *eind;
504
505 edir = (struct elf64_x86_64_link_hash_entry *) dir;
506 eind = (struct elf64_x86_64_link_hash_entry *) ind;
507
508 if (eind->dyn_relocs != NULL)
509 {
510 if (edir->dyn_relocs != NULL)
511 {
512 struct elf64_x86_64_dyn_relocs **pp;
513 struct elf64_x86_64_dyn_relocs *p;
514
515 if (ind->root.type == bfd_link_hash_indirect)
516 abort ();
517
518 /* Add reloc counts against the weak sym to the strong sym
519 list. Merge any entries against the same section. */
520 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
521 {
522 struct elf64_x86_64_dyn_relocs *q;
523
524 for (q = edir->dyn_relocs; q != NULL; q = q->next)
525 if (q->sec == p->sec)
526 {
527 q->pc_count += p->pc_count;
528 q->count += p->count;
529 *pp = p->next;
530 break;
531 }
532 if (q == NULL)
533 pp = &p->next;
534 }
535 *pp = edir->dyn_relocs;
536 }
537
538 edir->dyn_relocs = eind->dyn_relocs;
539 eind->dyn_relocs = NULL;
540 }
541
542 _bfd_elf_link_hash_copy_indirect (dir, ind);
543 }
544
545 static boolean
546 elf64_x86_64_elf_object_p (abfd)
547 bfd *abfd;
548 {
549 /* Set the right machine number for an x86-64 elf64 file. */
550 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
551 return true;
552 }
553
554 /* Look through the relocs for a section during the first phase, and
555 calculate needed space in the global offset table, procedure
556 linkage table, and dynamic reloc sections. */
557
558 static boolean
559 elf64_x86_64_check_relocs (abfd, info, sec, relocs)
560 bfd *abfd;
561 struct bfd_link_info *info;
562 asection *sec;
563 const Elf_Internal_Rela *relocs;
564 {
565 struct elf64_x86_64_link_hash_table *htab;
566 Elf_Internal_Shdr *symtab_hdr;
567 struct elf_link_hash_entry **sym_hashes;
568 const Elf_Internal_Rela *rel;
569 const Elf_Internal_Rela *rel_end;
570 asection *sreloc;
571
572 if (info->relocateable)
573 return true;
574
575 htab = elf64_x86_64_hash_table (info);
576 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
577 sym_hashes = elf_sym_hashes (abfd);
578
579 sreloc = NULL;
580
581 rel_end = relocs + sec->reloc_count;
582 for (rel = relocs; rel < rel_end; rel++)
583 {
584 unsigned long r_symndx;
585 struct elf_link_hash_entry *h;
586
587 r_symndx = ELF64_R_SYM (rel->r_info);
588
589 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
590 {
591 (*_bfd_error_handler) (_("%s: bad symbol index: %d"),
592 bfd_archive_filename (abfd),
593 r_symndx);
594 return false;
595 }
596
597 if (r_symndx < symtab_hdr->sh_info)
598 h = NULL;
599 else
600 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
601
602 switch (ELF64_R_TYPE (rel->r_info))
603 {
604 case R_X86_64_GOT32:
605 case R_X86_64_GOTPCREL:
606 /* This symbol requires a global offset table entry. */
607 if (h != NULL)
608 {
609 h->got.refcount += 1;
610 }
611 else
612 {
613 bfd_signed_vma *local_got_refcounts;
614
615 /* This is a global offset table entry for a local symbol. */
616 local_got_refcounts = elf_local_got_refcounts (abfd);
617 if (local_got_refcounts == NULL)
618 {
619 bfd_size_type size;
620
621 size = symtab_hdr->sh_info;
622 size *= sizeof (bfd_signed_vma);
623 local_got_refcounts = ((bfd_signed_vma *)
624 bfd_zalloc (abfd, size));
625 if (local_got_refcounts == NULL)
626 return false;
627 elf_local_got_refcounts (abfd) = local_got_refcounts;
628 }
629 local_got_refcounts[r_symndx] += 1;
630 }
631 /* Fall through */
632
633 //case R_X86_64_GOTPCREL:
634 if (htab->sgot == NULL)
635 {
636 if (htab->elf.dynobj == NULL)
637 htab->elf.dynobj = abfd;
638 if (!create_got_section (htab->elf.dynobj, info))
639 return false;
640 }
641 break;
642
643 case R_X86_64_PLT32:
644 /* This symbol requires a procedure linkage table entry. We
645 actually build the entry in adjust_dynamic_symbol,
646 because this might be a case of linking PIC code which is
647 never referenced by a dynamic object, in which case we
648 don't need to generate a procedure linkage table entry
649 after all. */
650
651 /* If this is a local symbol, we resolve it directly without
652 creating a procedure linkage table entry. */
653 if (h == NULL)
654 continue;
655
656 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
657 h->plt.refcount += 1;
658 break;
659
660 case R_X86_64_8:
661 case R_X86_64_16:
662 case R_X86_64_32:
663 case R_X86_64_32S:
664 /* Let's help debug shared library creation. These relocs
665 cannot be used in shared libs. Don't error out for
666 sections we don't care about, such as debug sections or
667 non-constant sections. */
668 if (info->shared
669 && (sec->flags & SEC_ALLOC) != 0
670 && (sec->flags & SEC_READONLY) != 0)
671 {
672 (*_bfd_error_handler)
673 (_("%s: relocation %s can not be used when making a shared object; recompile with -fPIC"),
674 bfd_archive_filename (abfd),
675 x86_64_elf_howto_table[ELF64_R_TYPE (rel->r_info)].name);
676 bfd_set_error (bfd_error_bad_value);
677 return false;
678 }
679 /* Fall through. */
680
681 case R_X86_64_PC8:
682 case R_X86_64_PC16:
683 case R_X86_64_PC32:
684 case R_X86_64_64:
685 if (h != NULL && !info->shared)
686 {
687 /* If this reloc is in a read-only section, we might
688 need a copy reloc. We can't check reliably at this
689 stage whether the section is read-only, as input
690 sections have not yet been mapped to output sections.
691 Tentatively set the flag for now, and correct in
692 adjust_dynamic_symbol. */
693 h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF;
694
695 /* We may need a .plt entry if the function this reloc
696 refers to is in a shared lib. */
697 h->plt.refcount += 1;
698 }
699
700 /* If we are creating a shared library, and this is a reloc
701 against a global symbol, or a non PC relative reloc
702 against a local symbol, then we need to copy the reloc
703 into the shared library. However, if we are linking with
704 -Bsymbolic, we do not need to copy a reloc against a
705 global symbol which is defined in an object we are
706 including in the link (i.e., DEF_REGULAR is set). At
707 this point we have not seen all the input files, so it is
708 possible that DEF_REGULAR is not set now but will be set
709 later (it is never cleared). In case of a weak definition,
710 DEF_REGULAR may be cleared later by a strong definition in
711 a shared library. We account for that possibility below by
712 storing information in the relocs_copied field of the hash
713 table entry. A similar situation occurs when creating
714 shared libraries and symbol visibility changes render the
715 symbol local.
716
717 If on the other hand, we are creating an executable, we
718 may need to keep relocations for symbols satisfied by a
719 dynamic library if we manage to avoid copy relocs for the
720 symbol. */
721 if ((info->shared
722 && (sec->flags & SEC_ALLOC) != 0
723 && (((ELF64_R_TYPE (rel->r_info) != R_X86_64_PC8)
724 && (ELF64_R_TYPE (rel->r_info) != R_X86_64_PC16)
725 && (ELF64_R_TYPE (rel->r_info) != R_X86_64_PC32))
726 || (h != NULL
727 && (! info->symbolic
728 || h->root.type == bfd_link_hash_defweak
729 || (h->elf_link_hash_flags
730 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
731 || (!info->shared
732 && (sec->flags & SEC_ALLOC) != 0
733 && h != NULL
734 && (h->root.type == bfd_link_hash_defweak
735 || (h->elf_link_hash_flags
736 & ELF_LINK_HASH_DEF_REGULAR) == 0)))
737 {
738 struct elf64_x86_64_dyn_relocs *p;
739 struct elf64_x86_64_dyn_relocs **head;
740
741 /* We must copy these reloc types into the output file.
742 Create a reloc section in dynobj and make room for
743 this reloc. */
744 if (sreloc == NULL)
745 {
746 const char *name;
747 bfd *dynobj;
748
749 name = (bfd_elf_string_from_elf_section
750 (abfd,
751 elf_elfheader (abfd)->e_shstrndx,
752 elf_section_data (sec)->rel_hdr.sh_name));
753 if (name == NULL)
754 return false;
755
756 if (strncmp (name, ".rela", 5) != 0
757 || strcmp (bfd_get_section_name (abfd, sec),
758 name + 5) != 0)
759 {
760 (*_bfd_error_handler)
761 (_("%s: bad relocation section name `%s\'"),
762 bfd_archive_filename (abfd), name);
763 }
764
765 if (htab->elf.dynobj == NULL)
766 htab->elf.dynobj = abfd;
767
768 dynobj = htab->elf.dynobj;
769
770 sreloc = bfd_get_section_by_name (dynobj, name);
771 if (sreloc == NULL)
772 {
773 flagword flags;
774
775 sreloc = bfd_make_section (dynobj, name);
776 flags = (SEC_HAS_CONTENTS | SEC_READONLY
777 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
778 if ((sec->flags & SEC_ALLOC) != 0)
779 flags |= SEC_ALLOC | SEC_LOAD;
780 if (sreloc == NULL
781 || ! bfd_set_section_flags (dynobj, sreloc, flags)
782 || ! bfd_set_section_alignment (dynobj, sreloc, 3))
783 return false;
784 }
785 elf_section_data (sec)->sreloc = sreloc;
786 }
787
788 /* If this is a global symbol, we count the number of
789 relocations we need for this symbol. */
790 if (h != NULL)
791 {
792 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs;
793 }
794 else
795 {
796 /* Track dynamic relocs needed for local syms too.
797 We really need local syms available to do this
798 easily. Oh well. */
799
800 asection *s;
801 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
802 sec, r_symndx);
803 if (s == NULL)
804 return false;
805
806 head = ((struct elf64_x86_64_dyn_relocs **)
807 &elf_section_data (s)->local_dynrel);
808 }
809
810 p = *head;
811 if (p == NULL || p->sec != sec)
812 {
813 bfd_size_type amt = sizeof *p;
814 p = ((struct elf64_x86_64_dyn_relocs *)
815 bfd_alloc (htab->elf.dynobj, amt));
816 if (p == NULL)
817 return false;
818 p->next = *head;
819 *head = p;
820 p->sec = sec;
821 p->count = 0;
822 p->pc_count = 0;
823 }
824
825 p->count += 1;
826 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_PC8
827 || ELF64_R_TYPE (rel->r_info) == R_X86_64_PC16
828 || ELF64_R_TYPE (rel->r_info) == R_X86_64_PC32)
829 p->pc_count += 1;
830 }
831 break;
832
833 /* This relocation describes the C++ object vtable hierarchy.
834 Reconstruct it for later use during GC. */
835 case R_X86_64_GNU_VTINHERIT:
836 if (!_bfd_elf64_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
837 return false;
838 break;
839
840 /* This relocation describes which C++ vtable entries are actually
841 used. Record for later use during GC. */
842 case R_X86_64_GNU_VTENTRY:
843 if (!_bfd_elf64_gc_record_vtentry (abfd, sec, h, rel->r_addend))
844 return false;
845 break;
846
847 default:
848 break;
849 }
850 }
851
852 return true;
853 }
854
855 /* Return the section that should be marked against GC for a given
856 relocation. */
857
858 static asection *
859 elf64_x86_64_gc_mark_hook (sec, info, rel, h, sym)
860 asection *sec;
861 struct bfd_link_info *info ATTRIBUTE_UNUSED;
862 Elf_Internal_Rela *rel;
863 struct elf_link_hash_entry *h;
864 Elf_Internal_Sym *sym;
865 {
866 if (h != NULL)
867 {
868 switch (ELF64_R_TYPE (rel->r_info))
869 {
870 case R_X86_64_GNU_VTINHERIT:
871 case R_X86_64_GNU_VTENTRY:
872 break;
873
874 default:
875 switch (h->root.type)
876 {
877 case bfd_link_hash_defined:
878 case bfd_link_hash_defweak:
879 return h->root.u.def.section;
880
881 case bfd_link_hash_common:
882 return h->root.u.c.p->section;
883
884 default:
885 break;
886 }
887 }
888 }
889 else
890 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
891
892 return NULL;
893 }
894
895 /* Update the got entry reference counts for the section being removed. */
896
897 static boolean
898 elf64_x86_64_gc_sweep_hook (abfd, info, sec, relocs)
899 bfd *abfd;
900 struct bfd_link_info *info;
901 asection *sec;
902 const Elf_Internal_Rela *relocs;
903 {
904 Elf_Internal_Shdr *symtab_hdr;
905 struct elf_link_hash_entry **sym_hashes;
906 bfd_signed_vma *local_got_refcounts;
907 const Elf_Internal_Rela *rel, *relend;
908 unsigned long r_symndx;
909 struct elf_link_hash_entry *h;
910
911 elf_section_data (sec)->local_dynrel = NULL;
912
913 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
914 sym_hashes = elf_sym_hashes (abfd);
915 local_got_refcounts = elf_local_got_refcounts (abfd);
916
917 relend = relocs + sec->reloc_count;
918 for (rel = relocs; rel < relend; rel++)
919 switch (ELF64_R_TYPE (rel->r_info))
920 {
921 case R_X86_64_GOT32:
922 case R_X86_64_GOTPCREL:
923 r_symndx = ELF64_R_SYM (rel->r_info);
924 if (r_symndx >= symtab_hdr->sh_info)
925 {
926 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
927 if (h->got.refcount > 0)
928 h->got.refcount -= 1;
929 }
930 else if (local_got_refcounts != NULL)
931 {
932 if (local_got_refcounts[r_symndx] > 0)
933 local_got_refcounts[r_symndx] -= 1;
934 }
935 break;
936
937 case R_X86_64_8:
938 case R_X86_64_16:
939 case R_X86_64_32:
940 case R_X86_64_64:
941 case R_X86_64_32S:
942 case R_X86_64_PC8:
943 case R_X86_64_PC16:
944 case R_X86_64_PC32:
945 r_symndx = ELF64_R_SYM (rel->r_info);
946 if (r_symndx >= symtab_hdr->sh_info)
947 {
948 struct elf64_x86_64_link_hash_entry *eh;
949 struct elf64_x86_64_dyn_relocs **pp;
950 struct elf64_x86_64_dyn_relocs *p;
951
952 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
953
954 if (!info->shared && h->plt.refcount > 0)
955 h->plt.refcount -= 1;
956
957 eh = (struct elf64_x86_64_link_hash_entry *) h;
958
959 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
960 if (p->sec == sec)
961 {
962 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_PC8
963 || ELF64_R_TYPE (rel->r_info) == R_X86_64_PC16
964 || ELF64_R_TYPE (rel->r_info) == R_X86_64_PC32)
965 p->pc_count -= 1;
966 p->count -= 1;
967 if (p->count == 0)
968 *pp = p->next;
969 break;
970 }
971 }
972 break;
973
974
975 case R_X86_64_PLT32:
976 r_symndx = ELF64_R_SYM (rel->r_info);
977 if (r_symndx >= symtab_hdr->sh_info)
978 {
979 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
980 if (h->plt.refcount > 0)
981 h->plt.refcount -= 1;
982 }
983 break;
984
985 default:
986 break;
987 }
988
989 return true;
990 }
991
992 /* Adjust a symbol defined by a dynamic object and referenced by a
993 regular object. The current definition is in some section of the
994 dynamic object, but we're not including those sections. We have to
995 change the definition to something the rest of the link can
996 understand. */
997
998 static boolean
999 elf64_x86_64_adjust_dynamic_symbol (info, h)
1000 struct bfd_link_info *info;
1001 struct elf_link_hash_entry *h;
1002 {
1003 struct elf64_x86_64_link_hash_table *htab;
1004 struct elf64_x86_64_link_hash_entry * eh;
1005 struct elf64_x86_64_dyn_relocs *p;
1006 asection *s;
1007 unsigned int power_of_two;
1008
1009 /* If this is a function, put it in the procedure linkage table. We
1010 will fill in the contents of the procedure linkage table later,
1011 when we know the address of the .got section. */
1012 if (h->type == STT_FUNC
1013 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
1014 {
1015 if (h->plt.refcount <= 0
1016 || (! info->shared
1017 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
1018 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0
1019 && h->root.type != bfd_link_hash_undefweak
1020 && h->root.type != bfd_link_hash_undefined))
1021 {
1022 /* This case can occur if we saw a PLT32 reloc in an input
1023 file, but the symbol was never referred to by a dynamic
1024 object, or if all references were garbage collected. In
1025 such a case, we don't actually need to build a procedure
1026 linkage table, and we can just do a PC32 reloc instead. */
1027 h->plt.offset = (bfd_vma) -1;
1028 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1029 }
1030
1031 return true;
1032 }
1033 else
1034 /* It's possible that we incorrectly decided a .plt reloc was
1035 needed for an R_X86_64_PC32 reloc to a non-function sym in
1036 check_relocs. We can't decide accurately between function and
1037 non-function syms in check-relocs; Objects loaded later in
1038 the link may change h->type. So fix it now. */
1039 h->plt.offset = (bfd_vma) -1;
1040
1041 /* If this is a weak symbol, and there is a real definition, the
1042 processor independent code will have arranged for us to see the
1043 real definition first, and we can just use the same value. */
1044 if (h->weakdef != NULL)
1045 {
1046 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
1047 || h->weakdef->root.type == bfd_link_hash_defweak);
1048 h->root.u.def.section = h->weakdef->root.u.def.section;
1049 h->root.u.def.value = h->weakdef->root.u.def.value;
1050 return true;
1051 }
1052
1053 /* This is a reference to a symbol defined by a dynamic object which
1054 is not a function. */
1055
1056 /* If we are creating a shared library, we must presume that the
1057 only references to the symbol are via the global offset table.
1058 For such cases we need not do anything here; the relocations will
1059 be handled correctly by relocate_section. */
1060 if (info->shared)
1061 return true;
1062
1063 /* If there are no references to this symbol that do not use the
1064 GOT, we don't need to generate a copy reloc. */
1065 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0)
1066 return true;
1067
1068 /* If -z nocopyreloc was given, we won't generate them either. */
1069 if (info->nocopyreloc)
1070 {
1071 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1072 return true;
1073 }
1074
1075 eh = (struct elf64_x86_64_link_hash_entry *) h;
1076 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1077 {
1078 s = p->sec->output_section;
1079 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1080 break;
1081 }
1082
1083 /* If we didn't find any dynamic relocs in read-only sections, then
1084 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1085 if (p == NULL)
1086 {
1087 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1088 return true;
1089 }
1090
1091 /* We must allocate the symbol in our .dynbss section, which will
1092 become part of the .bss section of the executable. There will be
1093 an entry for this symbol in the .dynsym section. The dynamic
1094 object will contain position independent code, so all references
1095 from the dynamic object to this symbol will go through the global
1096 offset table. The dynamic linker will use the .dynsym entry to
1097 determine the address it must put in the global offset table, so
1098 both the dynamic object and the regular object will refer to the
1099 same memory location for the variable. */
1100
1101 htab = elf64_x86_64_hash_table (info);
1102
1103 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
1104 to copy the initial value out of the dynamic object and into the
1105 runtime process image. */
1106 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1107 {
1108 htab->srelbss->_raw_size += sizeof (Elf64_External_Rela);
1109 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
1110 }
1111
1112 /* We need to figure out the alignment required for this symbol. I
1113 have no idea how ELF linkers handle this. 16-bytes is the size
1114 of the largest type that requires hard alignment -- long double. */
1115 /* FIXME: This is VERY ugly. Should be fixed for all architectures using
1116 this construct. */
1117 power_of_two = bfd_log2 (h->size);
1118 if (power_of_two > 4)
1119 power_of_two = 4;
1120
1121 /* Apply the required alignment. */
1122 s = htab->sdynbss;
1123 s->_raw_size = BFD_ALIGN (s->_raw_size, (bfd_size_type) (1 << power_of_two));
1124 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1125 {
1126 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1127 return false;
1128 }
1129
1130 /* Define the symbol as being at this point in the section. */
1131 h->root.u.def.section = s;
1132 h->root.u.def.value = s->_raw_size;
1133
1134 /* Increment the section size to make room for the symbol. */
1135 s->_raw_size += h->size;
1136
1137 return true;
1138 }
1139
1140 /* This is the condition under which elf64_x86_64_finish_dynamic_symbol
1141 will be called from elflink.h. If elflink.h doesn't call our
1142 finish_dynamic_symbol routine, we'll need to do something about
1143 initializing any .plt and .got entries in elf64_x86_64_relocate_section. */
1144 #define WILL_CALL_FINISH_DYNAMIC_SYMBOL(DYN, INFO, H) \
1145 ((DYN) \
1146 && ((INFO)->shared \
1147 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) \
1148 && ((H)->dynindx != -1 \
1149 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0))
1150
1151 /* Allocate space in .plt, .got and associated reloc sections for
1152 dynamic relocs. */
1153
1154 static boolean
1155 allocate_dynrelocs (h, inf)
1156 struct elf_link_hash_entry *h;
1157 PTR inf;
1158 {
1159 struct bfd_link_info *info;
1160 struct elf64_x86_64_link_hash_table *htab;
1161 struct elf64_x86_64_link_hash_entry *eh;
1162 struct elf64_x86_64_dyn_relocs *p;
1163
1164 if (h->root.type == bfd_link_hash_indirect)
1165 return true;
1166
1167 if (h->root.type == bfd_link_hash_warning)
1168 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1169
1170 info = (struct bfd_link_info *) inf;
1171 htab = elf64_x86_64_hash_table (info);
1172
1173 if (htab->elf.dynamic_sections_created
1174 && h->plt.refcount > 0)
1175 {
1176 /* Make sure this symbol is output as a dynamic symbol.
1177 Undefined weak syms won't yet be marked as dynamic. */
1178 if (h->dynindx == -1
1179 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1180 {
1181 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1182 return false;
1183 }
1184
1185 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, info, h))
1186 {
1187 asection *s = htab->splt;
1188
1189 /* If this is the first .plt entry, make room for the special
1190 first entry. */
1191 if (s->_raw_size == 0)
1192 s->_raw_size += PLT_ENTRY_SIZE;
1193
1194 h->plt.offset = s->_raw_size;
1195
1196 /* If this symbol is not defined in a regular file, and we are
1197 not generating a shared library, then set the symbol to this
1198 location in the .plt. This is required to make function
1199 pointers compare as equal between the normal executable and
1200 the shared library. */
1201 if (! info->shared
1202 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1203 {
1204 h->root.u.def.section = s;
1205 h->root.u.def.value = h->plt.offset;
1206 }
1207
1208 /* Make room for this entry. */
1209 s->_raw_size += PLT_ENTRY_SIZE;
1210
1211 /* We also need to make an entry in the .got.plt section, which
1212 will be placed in the .got section by the linker script. */
1213 htab->sgotplt->_raw_size += GOT_ENTRY_SIZE;
1214
1215 /* We also need to make an entry in the .rela.plt section. */
1216 htab->srelplt->_raw_size += sizeof (Elf64_External_Rela);
1217 }
1218 else
1219 {
1220 h->plt.offset = (bfd_vma) -1;
1221 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1222 }
1223 }
1224 else
1225 {
1226 h->plt.offset = (bfd_vma) -1;
1227 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1228 }
1229
1230 if (h->got.refcount > 0)
1231 {
1232 asection *s;
1233 boolean dyn;
1234
1235 /* Make sure this symbol is output as a dynamic symbol.
1236 Undefined weak syms won't yet be marked as dynamic. */
1237 if (h->dynindx == -1
1238 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1239 {
1240 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1241 return false;
1242 }
1243
1244 s = htab->sgot;
1245 h->got.offset = s->_raw_size;
1246 s->_raw_size += GOT_ENTRY_SIZE;
1247 dyn = htab->elf.dynamic_sections_created;
1248 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h))
1249 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1250 }
1251 else
1252 h->got.offset = (bfd_vma) -1;
1253
1254 eh = (struct elf64_x86_64_link_hash_entry *) h;
1255 if (eh->dyn_relocs == NULL)
1256 return true;
1257
1258 /* In the shared -Bsymbolic case, discard space allocated for
1259 dynamic pc-relative relocs against symbols which turn out to be
1260 defined in regular objects. For the normal shared case, discard
1261 space for pc-relative relocs that have become local due to symbol
1262 visibility changes. */
1263
1264 if (info->shared)
1265 {
1266 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
1267 && ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0
1268 || info->symbolic))
1269 {
1270 struct elf64_x86_64_dyn_relocs **pp;
1271
1272 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1273 {
1274 p->count -= p->pc_count;
1275 p->pc_count = 0;
1276 if (p->count == 0)
1277 *pp = p->next;
1278 else
1279 pp = &p->next;
1280 }
1281 }
1282 }
1283 else
1284 {
1285 /* For the non-shared case, discard space for relocs against
1286 symbols which turn out to need copy relocs or are not
1287 dynamic. */
1288
1289 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1290 && (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1291 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1292 || (htab->elf.dynamic_sections_created
1293 && (h->root.type == bfd_link_hash_undefweak
1294 || h->root.type == bfd_link_hash_undefined))))
1295 {
1296 /* Make sure this symbol is output as a dynamic symbol.
1297 Undefined weak syms won't yet be marked as dynamic. */
1298 if (h->dynindx == -1
1299 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1300 {
1301 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1302 return false;
1303 }
1304
1305 /* If that succeeded, we know we'll be keeping all the
1306 relocs. */
1307 if (h->dynindx != -1)
1308 goto keep;
1309 }
1310
1311 eh->dyn_relocs = NULL;
1312
1313 keep: ;
1314 }
1315
1316 /* Finally, allocate space. */
1317 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1318 {
1319 asection *sreloc = elf_section_data (p->sec)->sreloc;
1320 sreloc->_raw_size += p->count * sizeof (Elf64_External_Rela);
1321 }
1322
1323 return true;
1324 }
1325
1326 /* Find any dynamic relocs that apply to read-only sections. */
1327
1328 static boolean
1329 readonly_dynrelocs (h, inf)
1330 struct elf_link_hash_entry *h;
1331 PTR inf;
1332 {
1333 struct elf64_x86_64_link_hash_entry *eh;
1334 struct elf64_x86_64_dyn_relocs *p;
1335
1336 if (h->root.type == bfd_link_hash_warning)
1337 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1338
1339 eh = (struct elf64_x86_64_link_hash_entry *) h;
1340 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1341 {
1342 asection *s = p->sec->output_section;
1343
1344 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1345 {
1346 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1347
1348 info->flags |= DF_TEXTREL;
1349
1350 /* Not an error, just cut short the traversal. */
1351 return false;
1352 }
1353 }
1354 return true;
1355 }
1356
1357 /* Set the sizes of the dynamic sections. */
1358
1359 static boolean
1360 elf64_x86_64_size_dynamic_sections (output_bfd, info)
1361 bfd *output_bfd ATTRIBUTE_UNUSED;
1362 struct bfd_link_info *info;
1363 {
1364 struct elf64_x86_64_link_hash_table *htab;
1365 bfd *dynobj;
1366 asection *s;
1367 boolean relocs;
1368 bfd *ibfd;
1369
1370 htab = elf64_x86_64_hash_table (info);
1371 dynobj = htab->elf.dynobj;
1372 if (dynobj == NULL)
1373 abort ();
1374
1375 if (htab->elf.dynamic_sections_created)
1376 {
1377 /* Set the contents of the .interp section to the interpreter. */
1378 if (! info->shared)
1379 {
1380 s = bfd_get_section_by_name (dynobj, ".interp");
1381 if (s == NULL)
1382 abort ();
1383 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
1384 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1385 }
1386 }
1387
1388 /* Set up .got offsets for local syms, and space for local dynamic
1389 relocs. */
1390 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1391 {
1392 bfd_signed_vma *local_got;
1393 bfd_signed_vma *end_local_got;
1394 bfd_size_type locsymcount;
1395 Elf_Internal_Shdr *symtab_hdr;
1396 asection *srel;
1397
1398 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1399 continue;
1400
1401 for (s = ibfd->sections; s != NULL; s = s->next)
1402 {
1403 struct elf64_x86_64_dyn_relocs *p;
1404
1405 for (p = *((struct elf64_x86_64_dyn_relocs **)
1406 &elf_section_data (s)->local_dynrel);
1407 p != NULL;
1408 p = p->next)
1409 {
1410 if (!bfd_is_abs_section (p->sec)
1411 && bfd_is_abs_section (p->sec->output_section))
1412 {
1413 /* Input section has been discarded, either because
1414 it is a copy of a linkonce section or due to
1415 linker script /DISCARD/, so we'll be discarding
1416 the relocs too. */
1417 }
1418 else if (p->count != 0)
1419 {
1420 srel = elf_section_data (p->sec)->sreloc;
1421 srel->_raw_size += p->count * sizeof (Elf64_External_Rela);
1422 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1423 info->flags |= DF_TEXTREL;
1424
1425 }
1426 }
1427 }
1428
1429 local_got = elf_local_got_refcounts (ibfd);
1430 if (!local_got)
1431 continue;
1432
1433 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1434 locsymcount = symtab_hdr->sh_info;
1435 end_local_got = local_got + locsymcount;
1436 s = htab->sgot;
1437 srel = htab->srelgot;
1438 for (; local_got < end_local_got; ++local_got)
1439 {
1440 if (*local_got > 0)
1441 {
1442 *local_got = s->_raw_size;
1443 s->_raw_size += GOT_ENTRY_SIZE;
1444 if (info->shared)
1445 srel->_raw_size += sizeof (Elf64_External_Rela);
1446 }
1447 else
1448 *local_got = (bfd_vma) -1;
1449 }
1450 }
1451
1452 /* Allocate global sym .plt and .got entries, and space for global
1453 sym dynamic relocs. */
1454 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1455
1456 /* We now have determined the sizes of the various dynamic sections.
1457 Allocate memory for them. */
1458 relocs = false;
1459 for (s = dynobj->sections; s != NULL; s = s->next)
1460 {
1461 if ((s->flags & SEC_LINKER_CREATED) == 0)
1462 continue;
1463
1464 if (s == htab->splt
1465 || s == htab->sgot
1466 || s == htab->sgotplt)
1467 {
1468 /* Strip this section if we don't need it; see the
1469 comment below. */
1470 }
1471 else if (strncmp (bfd_get_section_name (dynobj, s), ".rela", 5) == 0)
1472 {
1473 if (s->_raw_size != 0 && s != htab->srelplt)
1474 relocs = true;
1475
1476 /* We use the reloc_count field as a counter if we need
1477 to copy relocs into the output file. */
1478 s->reloc_count = 0;
1479 }
1480 else
1481 {
1482 /* It's not one of our sections, so don't allocate space. */
1483 continue;
1484 }
1485
1486 if (s->_raw_size == 0)
1487 {
1488 /* If we don't need this section, strip it from the
1489 output file. This is mostly to handle .rela.bss and
1490 .rela.plt. We must create both sections in
1491 create_dynamic_sections, because they must be created
1492 before the linker maps input sections to output
1493 sections. The linker does that before
1494 adjust_dynamic_symbol is called, and it is that
1495 function which decides whether anything needs to go
1496 into these sections. */
1497
1498 _bfd_strip_section_from_output (info, s);
1499 continue;
1500 }
1501
1502 /* Allocate memory for the section contents. We use bfd_zalloc
1503 here in case unused entries are not reclaimed before the
1504 section's contents are written out. This should not happen,
1505 but this way if it does, we get a R_X86_64_NONE reloc instead
1506 of garbage. */
1507 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
1508 if (s->contents == NULL)
1509 return false;
1510 }
1511
1512 if (htab->elf.dynamic_sections_created)
1513 {
1514 /* Add some entries to the .dynamic section. We fill in the
1515 values later, in elf64_x86_64_finish_dynamic_sections, but we
1516 must add the entries now so that we get the correct size for
1517 the .dynamic section. The DT_DEBUG entry is filled in by the
1518 dynamic linker and used by the debugger. */
1519 #define add_dynamic_entry(TAG, VAL) \
1520 bfd_elf64_add_dynamic_entry (info, (bfd_vma) (TAG), (bfd_vma) (VAL))
1521
1522 if (! info->shared)
1523 {
1524 if (!add_dynamic_entry (DT_DEBUG, 0))
1525 return false;
1526 }
1527
1528 if (htab->splt->_raw_size != 0)
1529 {
1530 if (!add_dynamic_entry (DT_PLTGOT, 0)
1531 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1532 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1533 || !add_dynamic_entry (DT_JMPREL, 0))
1534 return false;
1535 }
1536
1537 if (relocs)
1538 {
1539 if (!add_dynamic_entry (DT_RELA, 0)
1540 || !add_dynamic_entry (DT_RELASZ, 0)
1541 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
1542 return false;
1543
1544 /* If any dynamic relocs apply to a read-only section,
1545 then we need a DT_TEXTREL entry. */
1546 if ((info->flags & DF_TEXTREL) == 0)
1547 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
1548 (PTR) info);
1549
1550 if ((info->flags & DF_TEXTREL) != 0)
1551 {
1552 if (!add_dynamic_entry (DT_TEXTREL, 0))
1553 return false;
1554 }
1555 }
1556 }
1557 #undef add_dynamic_entry
1558
1559 return true;
1560 }
1561
1562 /* Relocate an x86_64 ELF section. */
1563
1564 static boolean
1565 elf64_x86_64_relocate_section (output_bfd, info, input_bfd, input_section,
1566 contents, relocs, local_syms, local_sections)
1567 bfd *output_bfd;
1568 struct bfd_link_info *info;
1569 bfd *input_bfd;
1570 asection *input_section;
1571 bfd_byte *contents;
1572 Elf_Internal_Rela *relocs;
1573 Elf_Internal_Sym *local_syms;
1574 asection **local_sections;
1575 {
1576 struct elf64_x86_64_link_hash_table *htab;
1577 Elf_Internal_Shdr *symtab_hdr;
1578 struct elf_link_hash_entry **sym_hashes;
1579 bfd_vma *local_got_offsets;
1580 Elf_Internal_Rela *rel;
1581 Elf_Internal_Rela *relend;
1582
1583 if (info->relocateable)
1584 return true;
1585
1586 htab = elf64_x86_64_hash_table (info);
1587 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1588 sym_hashes = elf_sym_hashes (input_bfd);
1589 local_got_offsets = elf_local_got_offsets (input_bfd);
1590
1591 rel = relocs;
1592 relend = relocs + input_section->reloc_count;
1593 for (; rel < relend; rel++)
1594 {
1595 int r_type;
1596 reloc_howto_type *howto;
1597 unsigned long r_symndx;
1598 struct elf_link_hash_entry *h;
1599 Elf_Internal_Sym *sym;
1600 asection *sec;
1601 bfd_vma off;
1602 bfd_vma relocation;
1603 boolean unresolved_reloc;
1604 bfd_reloc_status_type r;
1605
1606 r_type = ELF64_R_TYPE (rel->r_info);
1607 if (r_type == (int) R_X86_64_GNU_VTINHERIT
1608 || r_type == (int) R_X86_64_GNU_VTENTRY)
1609 continue;
1610
1611 if (r_type < 0 || r_type >= R_X86_64_max)
1612 {
1613 bfd_set_error (bfd_error_bad_value);
1614 return false;
1615 }
1616
1617 howto = x86_64_elf_howto_table + r_type;
1618 r_symndx = ELF64_R_SYM (rel->r_info);
1619 h = NULL;
1620 sym = NULL;
1621 sec = NULL;
1622 unresolved_reloc = false;
1623 if (r_symndx < symtab_hdr->sh_info)
1624 {
1625 sym = local_syms + r_symndx;
1626 sec = local_sections[r_symndx];
1627
1628 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, sec, rel);
1629 }
1630 else
1631 {
1632 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1633 while (h->root.type == bfd_link_hash_indirect
1634 || h->root.type == bfd_link_hash_warning)
1635 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1636
1637 if (h->root.type == bfd_link_hash_defined
1638 || h->root.type == bfd_link_hash_defweak)
1639 {
1640 sec = h->root.u.def.section;
1641 if (sec->output_section == NULL)
1642 {
1643 /* Set a flag that will be cleared later if we find a
1644 relocation value for this symbol. output_section
1645 is typically NULL for symbols satisfied by a shared
1646 library. */
1647 unresolved_reloc = true;
1648 relocation = 0;
1649 }
1650 else
1651 relocation = (h->root.u.def.value
1652 + sec->output_section->vma
1653 + sec->output_offset);
1654 }
1655 else if (h->root.type == bfd_link_hash_undefweak)
1656 relocation = 0;
1657 else if (info->shared
1658 && (!info->symbolic || info->allow_shlib_undefined)
1659 && !info->no_undefined
1660 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
1661 relocation = 0;
1662 else
1663 {
1664 if (! ((*info->callbacks->undefined_symbol)
1665 (info, h->root.root.string, input_bfd,
1666 input_section, rel->r_offset,
1667 (!info->shared || info->no_undefined
1668 || ELF_ST_VISIBILITY (h->other)))))
1669 return false;
1670 relocation = 0;
1671 }
1672 }
1673 /* When generating a shared object, the relocations handled here are
1674 copied into the output file to be resolved at run time. */
1675 switch (r_type)
1676 {
1677 case R_X86_64_GOT32:
1678 /* Relocation is to the entry for this symbol in the global
1679 offset table. */
1680 case R_X86_64_GOTPCREL:
1681 /* Use global offset table as symbol value. */
1682 if (htab->sgot == NULL)
1683 abort ();
1684
1685 if (h != NULL)
1686 {
1687 boolean dyn;
1688
1689 off = h->got.offset;
1690 dyn = htab->elf.dynamic_sections_created;
1691
1692 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h)
1693 || (info->shared
1694 && (info->symbolic
1695 || h->dynindx == -1
1696 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
1697 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1698 {
1699 /* This is actually a static link, or it is a -Bsymbolic
1700 link and the symbol is defined locally, or the symbol
1701 was forced to be local because of a version file. We
1702 must initialize this entry in the global offset table.
1703 Since the offset must always be a multiple of 8, we
1704 use the least significant bit to record whether we
1705 have initialized it already.
1706
1707 When doing a dynamic link, we create a .rela.got
1708 relocation entry to initialize the value. This is
1709 done in the finish_dynamic_symbol routine. */
1710 if ((off & 1) != 0)
1711 off &= ~1;
1712 else
1713 {
1714 bfd_put_64 (output_bfd, relocation,
1715 htab->sgot->contents + off);
1716 h->got.offset |= 1;
1717 }
1718 }
1719 else
1720 unresolved_reloc = false;
1721 }
1722 else
1723 {
1724 if (local_got_offsets == NULL)
1725 abort ();
1726
1727 off = local_got_offsets[r_symndx];
1728
1729 /* The offset must always be a multiple of 8. We use
1730 the least significant bit to record whether we have
1731 already generated the necessary reloc. */
1732 if ((off & 1) != 0)
1733 off &= ~1;
1734 else
1735 {
1736 bfd_put_64 (output_bfd, relocation,
1737 htab->sgot->contents + off);
1738
1739 if (info->shared)
1740 {
1741 asection *srelgot;
1742 Elf_Internal_Rela outrel;
1743 Elf64_External_Rela *loc;
1744
1745 /* We need to generate a R_X86_64_RELATIVE reloc
1746 for the dynamic linker. */
1747 srelgot = htab->srelgot;
1748 if (srelgot == NULL)
1749 abort ();
1750
1751 outrel.r_offset = (htab->sgot->output_section->vma
1752 + htab->sgot->output_offset
1753 + off);
1754 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
1755 outrel.r_addend = relocation;
1756 loc = (Elf64_External_Rela *) srelgot->contents;
1757 loc += srelgot->reloc_count++;
1758 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
1759 }
1760
1761 local_got_offsets[r_symndx] |= 1;
1762 }
1763 }
1764
1765 if (off >= (bfd_vma) -2)
1766 abort ();
1767
1768 relocation = htab->sgot->output_offset + off;
1769 if (r_type == R_X86_64_GOTPCREL)
1770 relocation += htab->sgot->output_section->vma;
1771
1772 break;
1773
1774 case R_X86_64_PLT32:
1775 /* Relocation is to the entry for this symbol in the
1776 procedure linkage table. */
1777
1778 /* Resolve a PLT32 reloc against a local symbol directly,
1779 without using the procedure linkage table. */
1780 if (h == NULL)
1781 break;
1782
1783 if (h->plt.offset == (bfd_vma) -1
1784 || htab->splt == NULL)
1785 {
1786 /* We didn't make a PLT entry for this symbol. This
1787 happens when statically linking PIC code, or when
1788 using -Bsymbolic. */
1789 break;
1790 }
1791
1792 relocation = (htab->splt->output_section->vma
1793 + htab->splt->output_offset
1794 + h->plt.offset);
1795 unresolved_reloc = false;
1796 break;
1797
1798 case R_X86_64_PC8:
1799 case R_X86_64_PC16:
1800 case R_X86_64_PC32:
1801 case R_X86_64_8:
1802 case R_X86_64_16:
1803 case R_X86_64_32:
1804 case R_X86_64_64:
1805 /* FIXME: The ABI says the linker should make sure the value is
1806 the same when it's zeroextended to 64 bit. */
1807
1808 /* r_symndx will be zero only for relocs against symbols
1809 from removed linkonce sections, or sections discarded by
1810 a linker script. */
1811 if (r_symndx == 0
1812 || (input_section->flags & SEC_ALLOC) == 0)
1813 break;
1814
1815 if ((info->shared
1816 && ((r_type != R_X86_64_PC8
1817 && r_type != R_X86_64_PC16
1818 && r_type != R_X86_64_PC32)
1819 || (h != NULL
1820 && h->dynindx != -1
1821 && (! info->symbolic
1822 || (h->elf_link_hash_flags
1823 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
1824 || (!info->shared
1825 && h != NULL
1826 && h->dynindx != -1
1827 && (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1828 && (((h->elf_link_hash_flags
1829 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1830 && (h->elf_link_hash_flags
1831 & ELF_LINK_HASH_DEF_REGULAR) == 0)
1832 || h->root.type == bfd_link_hash_undefweak
1833 || h->root.type == bfd_link_hash_undefined)))
1834 {
1835 Elf_Internal_Rela outrel;
1836 boolean skip, relocate;
1837 asection *sreloc;
1838 Elf64_External_Rela *loc;
1839
1840 /* When generating a shared object, these relocations
1841 are copied into the output file to be resolved at run
1842 time. */
1843
1844 skip = false;
1845 relocate = false;
1846
1847 outrel.r_offset =
1848 _bfd_elf_section_offset (output_bfd, info, input_section,
1849 rel->r_offset);
1850 if (outrel.r_offset == (bfd_vma) -1)
1851 skip = true;
1852 else if (outrel.r_offset == (bfd_vma) -2)
1853 skip = true, relocate = true;
1854
1855 outrel.r_offset += (input_section->output_section->vma
1856 + input_section->output_offset);
1857
1858 if (skip)
1859 memset (&outrel, 0, sizeof outrel);
1860
1861 /* h->dynindx may be -1 if this symbol was marked to
1862 become local. */
1863 else if (h != NULL
1864 && h->dynindx != -1
1865 && (r_type == R_X86_64_PC8
1866 || r_type == R_X86_64_PC16
1867 || r_type == R_X86_64_PC32
1868 || !info->shared
1869 || !info->symbolic
1870 || (h->elf_link_hash_flags
1871 & ELF_LINK_HASH_DEF_REGULAR) == 0))
1872 {
1873 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
1874 outrel.r_addend = rel->r_addend;
1875 }
1876 else
1877 {
1878 /* This symbol is local, or marked to become local. */
1879 relocate = true;
1880 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
1881 outrel.r_addend = relocation + rel->r_addend;
1882 }
1883
1884 sreloc = elf_section_data (input_section)->sreloc;
1885 if (sreloc == NULL)
1886 abort ();
1887
1888 loc = (Elf64_External_Rela *) sreloc->contents;
1889 loc += sreloc->reloc_count++;
1890 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
1891
1892 /* If this reloc is against an external symbol, we do
1893 not want to fiddle with the addend. Otherwise, we
1894 need to include the symbol value so that it becomes
1895 an addend for the dynamic reloc. */
1896 if (! relocate)
1897 continue;
1898 }
1899
1900 break;
1901
1902 default:
1903 break;
1904 }
1905
1906 /* FIXME: Why do we allow debugging sections to escape this error?
1907 More importantly, why do we not emit dynamic relocs for
1908 R_386_32 above in debugging sections (which are ! SEC_ALLOC)?
1909 If we had emitted the dynamic reloc, we could remove the
1910 fudge here. */
1911 if (unresolved_reloc
1912 && !(info->shared
1913 && (input_section->flags & SEC_DEBUGGING) != 0
1914 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
1915 (*_bfd_error_handler)
1916 (_("%s(%s+0x%lx): unresolvable relocation against symbol `%s'"),
1917 bfd_archive_filename (input_bfd),
1918 bfd_get_section_name (input_bfd, input_section),
1919 (long) rel->r_offset,
1920 h->root.root.string);
1921
1922 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
1923 contents, rel->r_offset,
1924 relocation, rel->r_addend);
1925
1926 if (r != bfd_reloc_ok)
1927 {
1928 const char *name;
1929
1930 if (h != NULL)
1931 name = h->root.root.string;
1932 else
1933 {
1934 name = bfd_elf_string_from_elf_section (input_bfd,
1935 symtab_hdr->sh_link,
1936 sym->st_name);
1937 if (name == NULL)
1938 return false;
1939 if (*name == '\0')
1940 name = bfd_section_name (input_bfd, sec);
1941 }
1942
1943 if (r == bfd_reloc_overflow)
1944 {
1945
1946 if (! ((*info->callbacks->reloc_overflow)
1947 (info, name, howto->name, (bfd_vma) 0,
1948 input_bfd, input_section, rel->r_offset)))
1949 return false;
1950 }
1951 else
1952 {
1953 (*_bfd_error_handler)
1954 (_("%s(%s+0x%lx): reloc against `%s': error %d"),
1955 bfd_archive_filename (input_bfd),
1956 bfd_get_section_name (input_bfd, input_section),
1957 (long) rel->r_offset, name, (int) r);
1958 return false;
1959 }
1960 }
1961 }
1962
1963 return true;
1964 }
1965
1966 /* Finish up dynamic symbol handling. We set the contents of various
1967 dynamic sections here. */
1968
1969 static boolean
1970 elf64_x86_64_finish_dynamic_symbol (output_bfd, info, h, sym)
1971 bfd *output_bfd;
1972 struct bfd_link_info *info;
1973 struct elf_link_hash_entry *h;
1974 Elf_Internal_Sym *sym;
1975 {
1976 struct elf64_x86_64_link_hash_table *htab;
1977
1978 htab = elf64_x86_64_hash_table (info);
1979
1980 if (h->plt.offset != (bfd_vma) -1)
1981 {
1982 bfd_vma plt_index;
1983 bfd_vma got_offset;
1984 Elf_Internal_Rela rela;
1985 Elf64_External_Rela *loc;
1986
1987 /* This symbol has an entry in the procedure linkage table. Set
1988 it up. */
1989
1990 if (h->dynindx == -1
1991 || htab->splt == NULL
1992 || htab->sgotplt == NULL
1993 || htab->srelplt == NULL)
1994 abort ();
1995
1996 /* Get the index in the procedure linkage table which
1997 corresponds to this symbol. This is the index of this symbol
1998 in all the symbols for which we are making plt entries. The
1999 first entry in the procedure linkage table is reserved. */
2000 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2001
2002 /* Get the offset into the .got table of the entry that
2003 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
2004 bytes. The first three are reserved for the dynamic linker. */
2005 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
2006
2007 /* Fill in the entry in the procedure linkage table. */
2008 memcpy (htab->splt->contents + h->plt.offset, elf64_x86_64_plt_entry,
2009 PLT_ENTRY_SIZE);
2010
2011 /* Insert the relocation positions of the plt section. The magic
2012 numbers at the end of the statements are the positions of the
2013 relocations in the plt section. */
2014 /* Put offset for jmp *name@GOTPCREL(%rip), since the
2015 instruction uses 6 bytes, subtract this value. */
2016 bfd_put_32 (output_bfd,
2017 (htab->sgotplt->output_section->vma
2018 + htab->sgotplt->output_offset
2019 + got_offset
2020 - htab->splt->output_section->vma
2021 - htab->splt->output_offset
2022 - h->plt.offset
2023 - 6),
2024 htab->splt->contents + h->plt.offset + 2);
2025 /* Put relocation index. */
2026 bfd_put_32 (output_bfd, plt_index,
2027 htab->splt->contents + h->plt.offset + 7);
2028 /* Put offset for jmp .PLT0. */
2029 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
2030 htab->splt->contents + h->plt.offset + 12);
2031
2032 /* Fill in the entry in the global offset table, initially this
2033 points to the pushq instruction in the PLT which is at offset 6. */
2034 bfd_put_64 (output_bfd, (htab->splt->output_section->vma
2035 + htab->splt->output_offset
2036 + h->plt.offset + 6),
2037 htab->sgotplt->contents + got_offset);
2038
2039 /* Fill in the entry in the .rela.plt section. */
2040 rela.r_offset = (htab->sgotplt->output_section->vma
2041 + htab->sgotplt->output_offset
2042 + got_offset);
2043 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
2044 rela.r_addend = 0;
2045 loc = (Elf64_External_Rela *) htab->srelplt->contents + plt_index;
2046 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2047
2048 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2049 {
2050 /* Mark the symbol as undefined, rather than as defined in
2051 the .plt section. Leave the value alone. This is a clue
2052 for the dynamic linker, to make function pointer
2053 comparisons work between an application and shared
2054 library. */
2055 sym->st_shndx = SHN_UNDEF;
2056 }
2057 }
2058
2059 if (h->got.offset != (bfd_vma) -1)
2060 {
2061 Elf_Internal_Rela rela;
2062 Elf64_External_Rela *loc;
2063
2064 /* This symbol has an entry in the global offset table. Set it
2065 up. */
2066
2067 if (htab->sgot == NULL || htab->srelgot == NULL)
2068 abort ();
2069
2070 rela.r_offset = (htab->sgot->output_section->vma
2071 + htab->sgot->output_offset
2072 + (h->got.offset &~ (bfd_vma) 1));
2073
2074 /* If this is a static link, or it is a -Bsymbolic link and the
2075 symbol is defined locally or was forced to be local because
2076 of a version file, we just want to emit a RELATIVE reloc.
2077 The entry in the global offset table will already have been
2078 initialized in the relocate_section function. */
2079 if (info->shared
2080 && (info->symbolic
2081 || h->dynindx == -1
2082 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
2083 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
2084 {
2085 BFD_ASSERT((h->got.offset & 1) != 0);
2086 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2087 rela.r_addend = (h->root.u.def.value
2088 + h->root.u.def.section->output_section->vma
2089 + h->root.u.def.section->output_offset);
2090 }
2091 else
2092 {
2093 BFD_ASSERT((h->got.offset & 1) == 0);
2094 bfd_put_64 (output_bfd, (bfd_vma) 0,
2095 htab->sgot->contents + h->got.offset);
2096 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
2097 rela.r_addend = 0;
2098 }
2099
2100 loc = (Elf64_External_Rela *) htab->srelgot->contents;
2101 loc += htab->srelgot->reloc_count++;
2102 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2103 }
2104
2105 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
2106 {
2107 Elf_Internal_Rela rela;
2108 Elf64_External_Rela *loc;
2109
2110 /* This symbol needs a copy reloc. Set it up. */
2111
2112 if (h->dynindx == -1
2113 || (h->root.type != bfd_link_hash_defined
2114 && h->root.type != bfd_link_hash_defweak)
2115 || htab->srelbss == NULL)
2116 abort ();
2117
2118 rela.r_offset = (h->root.u.def.value
2119 + h->root.u.def.section->output_section->vma
2120 + h->root.u.def.section->output_offset);
2121 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
2122 rela.r_addend = 0;
2123 loc = (Elf64_External_Rela *) htab->srelbss->contents;
2124 loc += htab->srelbss->reloc_count++;
2125 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2126 }
2127
2128 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
2129 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
2130 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
2131 sym->st_shndx = SHN_ABS;
2132
2133 return true;
2134 }
2135
2136 /* Used to decide how to sort relocs in an optimal manner for the
2137 dynamic linker, before writing them out. */
2138
2139 static enum elf_reloc_type_class
2140 elf64_x86_64_reloc_type_class (rela)
2141 const Elf_Internal_Rela *rela;
2142 {
2143 switch ((int) ELF64_R_TYPE (rela->r_info))
2144 {
2145 case R_X86_64_RELATIVE:
2146 return reloc_class_relative;
2147 case R_X86_64_JUMP_SLOT:
2148 return reloc_class_plt;
2149 case R_X86_64_COPY:
2150 return reloc_class_copy;
2151 default:
2152 return reloc_class_normal;
2153 }
2154 }
2155
2156 /* Finish up the dynamic sections. */
2157
2158 static boolean
2159 elf64_x86_64_finish_dynamic_sections (output_bfd, info)
2160 bfd *output_bfd;
2161 struct bfd_link_info *info;
2162 {
2163 struct elf64_x86_64_link_hash_table *htab;
2164 bfd *dynobj;
2165 asection *sdyn;
2166
2167 htab = elf64_x86_64_hash_table (info);
2168 dynobj = htab->elf.dynobj;
2169 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2170
2171 if (htab->elf.dynamic_sections_created)
2172 {
2173 Elf64_External_Dyn *dyncon, *dynconend;
2174
2175 if (sdyn == NULL || htab->sgot == NULL)
2176 abort ();
2177
2178 dyncon = (Elf64_External_Dyn *) sdyn->contents;
2179 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
2180 for (; dyncon < dynconend; dyncon++)
2181 {
2182 Elf_Internal_Dyn dyn;
2183 asection *s;
2184
2185 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
2186
2187 switch (dyn.d_tag)
2188 {
2189 default:
2190 continue;
2191
2192 case DT_PLTGOT:
2193 dyn.d_un.d_ptr = htab->sgot->output_section->vma;
2194 break;
2195
2196 case DT_JMPREL:
2197 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
2198 break;
2199
2200 case DT_PLTRELSZ:
2201 s = htab->srelplt->output_section;
2202 if (s->_cooked_size != 0)
2203 dyn.d_un.d_val = s->_cooked_size;
2204 else
2205 dyn.d_un.d_val = s->_raw_size;
2206 break;
2207
2208 case DT_RELASZ:
2209 /* The procedure linkage table relocs (DT_JMPREL) should
2210 not be included in the overall relocs (DT_RELA).
2211 Therefore, we override the DT_RELASZ entry here to
2212 make it not include the JMPREL relocs. Since the
2213 linker script arranges for .rela.plt to follow all
2214 other relocation sections, we don't have to worry
2215 about changing the DT_RELA entry. */
2216 if (htab->srelplt != NULL)
2217 {
2218 s = htab->srelplt->output_section;
2219 if (s->_cooked_size != 0)
2220 dyn.d_un.d_val -= s->_cooked_size;
2221 else
2222 dyn.d_un.d_val -= s->_raw_size;
2223 }
2224 break;
2225 }
2226
2227 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
2228 }
2229
2230 /* Fill in the special first entry in the procedure linkage table. */
2231 if (htab->splt && htab->splt->_raw_size > 0)
2232 {
2233 /* Fill in the first entry in the procedure linkage table. */
2234 memcpy (htab->splt->contents, elf64_x86_64_plt0_entry,
2235 PLT_ENTRY_SIZE);
2236 /* Add offset for pushq GOT+8(%rip), since the instruction
2237 uses 6 bytes subtract this value. */
2238 bfd_put_32 (output_bfd,
2239 (htab->sgotplt->output_section->vma
2240 + htab->sgotplt->output_offset
2241 + 8
2242 - htab->splt->output_section->vma
2243 - htab->splt->output_offset
2244 - 6),
2245 htab->splt->contents + 2);
2246 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
2247 the end of the instruction. */
2248 bfd_put_32 (output_bfd,
2249 (htab->sgotplt->output_section->vma
2250 + htab->sgotplt->output_offset
2251 + 16
2252 - htab->splt->output_section->vma
2253 - htab->splt->output_offset
2254 - 12),
2255 htab->splt->contents + 8);
2256
2257 elf_section_data (htab->splt->output_section)->this_hdr.sh_entsize =
2258 PLT_ENTRY_SIZE;
2259 }
2260 }
2261
2262 if (htab->sgotplt)
2263 {
2264 /* Fill in the first three entries in the global offset table. */
2265 if (htab->sgotplt->_raw_size > 0)
2266 {
2267 /* Set the first entry in the global offset table to the address of
2268 the dynamic section. */
2269 if (sdyn == NULL)
2270 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents);
2271 else
2272 bfd_put_64 (output_bfd,
2273 sdyn->output_section->vma + sdyn->output_offset,
2274 htab->sgotplt->contents);
2275 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
2276 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE);
2277 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE*2);
2278 }
2279
2280 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize =
2281 GOT_ENTRY_SIZE;
2282 }
2283
2284 return true;
2285 }
2286
2287
2288 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
2289 #define TARGET_LITTLE_NAME "elf64-x86-64"
2290 #define ELF_ARCH bfd_arch_i386
2291 #define ELF_MACHINE_CODE EM_X86_64
2292 #define ELF_MAXPAGESIZE 0x100000
2293
2294 #define elf_backend_can_gc_sections 1
2295 #define elf_backend_can_refcount 1
2296 #define elf_backend_want_got_plt 1
2297 #define elf_backend_plt_readonly 1
2298 #define elf_backend_want_plt_sym 0
2299 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
2300 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
2301 #define elf_backend_rela_normal 1
2302
2303 #define elf_info_to_howto elf64_x86_64_info_to_howto
2304
2305 #define bfd_elf64_bfd_link_hash_table_create \
2306 elf64_x86_64_link_hash_table_create
2307 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
2308
2309 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
2310 #define elf_backend_check_relocs elf64_x86_64_check_relocs
2311 #define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol
2312 #define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections
2313 #define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections
2314 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
2315 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
2316 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
2317 #define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus
2318 #define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo
2319 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
2320 #define elf_backend_relocate_section elf64_x86_64_relocate_section
2321 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
2322 #define elf_backend_object_p elf64_x86_64_elf_object_p
2323
2324 #include "elf64-target.h"
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