[ bfd/ChangeLog ]
[deliverable/binutils-gdb.git] / bfd / elf64-x86-64.c
1 /* X86-64 specific support for 64-bit ELF
2 Copyright 2000, 2001, 2002, 2003, 2004 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 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
30 #define MINUS_ONE (~ (bfd_vma) 0)
31
32 /* The relocation "howto" table. Order of fields:
33 type, size, bitsize, pc_relative, complain_on_overflow,
34 special_function, name, partial_inplace, src_mask, dst_pack, pcrel_offset. */
35 static reloc_howto_type x86_64_elf_howto_table[] =
36 {
37 HOWTO(R_X86_64_NONE, 0, 0, 0, FALSE, 0, complain_overflow_dont,
38 bfd_elf_generic_reloc, "R_X86_64_NONE", FALSE, 0x00000000, 0x00000000,
39 FALSE),
40 HOWTO(R_X86_64_64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
41 bfd_elf_generic_reloc, "R_X86_64_64", FALSE, MINUS_ONE, MINUS_ONE,
42 FALSE),
43 HOWTO(R_X86_64_PC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
44 bfd_elf_generic_reloc, "R_X86_64_PC32", FALSE, 0xffffffff, 0xffffffff,
45 TRUE),
46 HOWTO(R_X86_64_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
47 bfd_elf_generic_reloc, "R_X86_64_GOT32", FALSE, 0xffffffff, 0xffffffff,
48 FALSE),
49 HOWTO(R_X86_64_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
50 bfd_elf_generic_reloc, "R_X86_64_PLT32", FALSE, 0xffffffff, 0xffffffff,
51 TRUE),
52 HOWTO(R_X86_64_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
53 bfd_elf_generic_reloc, "R_X86_64_COPY", FALSE, 0xffffffff, 0xffffffff,
54 FALSE),
55 HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
56 bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", FALSE, MINUS_ONE,
57 MINUS_ONE, FALSE),
58 HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
59 bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", FALSE, MINUS_ONE,
60 MINUS_ONE, FALSE),
61 HOWTO(R_X86_64_RELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
62 bfd_elf_generic_reloc, "R_X86_64_RELATIVE", FALSE, MINUS_ONE,
63 MINUS_ONE, FALSE),
64 HOWTO(R_X86_64_GOTPCREL, 0, 2, 32, TRUE, 0, complain_overflow_signed,
65 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", FALSE, 0xffffffff,
66 0xffffffff, TRUE),
67 HOWTO(R_X86_64_32, 0, 2, 32, FALSE, 0, complain_overflow_unsigned,
68 bfd_elf_generic_reloc, "R_X86_64_32", FALSE, 0xffffffff, 0xffffffff,
69 FALSE),
70 HOWTO(R_X86_64_32S, 0, 2, 32, FALSE, 0, complain_overflow_signed,
71 bfd_elf_generic_reloc, "R_X86_64_32S", FALSE, 0xffffffff, 0xffffffff,
72 FALSE),
73 HOWTO(R_X86_64_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
74 bfd_elf_generic_reloc, "R_X86_64_16", FALSE, 0xffff, 0xffff, FALSE),
75 HOWTO(R_X86_64_PC16,0, 1, 16, TRUE, 0, complain_overflow_bitfield,
76 bfd_elf_generic_reloc, "R_X86_64_PC16", FALSE, 0xffff, 0xffff, TRUE),
77 HOWTO(R_X86_64_8, 0, 0, 8, FALSE, 0, complain_overflow_signed,
78 bfd_elf_generic_reloc, "R_X86_64_8", FALSE, 0xff, 0xff, FALSE),
79 HOWTO(R_X86_64_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed,
80 bfd_elf_generic_reloc, "R_X86_64_PC8", FALSE, 0xff, 0xff, TRUE),
81 HOWTO(R_X86_64_DTPMOD64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
82 bfd_elf_generic_reloc, "R_X86_64_DTPMOD64", FALSE, MINUS_ONE,
83 MINUS_ONE, FALSE),
84 HOWTO(R_X86_64_DTPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
85 bfd_elf_generic_reloc, "R_X86_64_DTPOFF64", FALSE, MINUS_ONE,
86 MINUS_ONE, FALSE),
87 HOWTO(R_X86_64_TPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
88 bfd_elf_generic_reloc, "R_X86_64_TPOFF64", FALSE, MINUS_ONE,
89 MINUS_ONE, FALSE),
90 HOWTO(R_X86_64_TLSGD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
91 bfd_elf_generic_reloc, "R_X86_64_TLSGD", FALSE, 0xffffffff,
92 0xffffffff, TRUE),
93 HOWTO(R_X86_64_TLSLD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
94 bfd_elf_generic_reloc, "R_X86_64_TLSLD", FALSE, 0xffffffff,
95 0xffffffff, TRUE),
96 HOWTO(R_X86_64_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
97 bfd_elf_generic_reloc, "R_X86_64_DTPOFF32", FALSE, 0xffffffff,
98 0xffffffff, FALSE),
99 HOWTO(R_X86_64_GOTTPOFF, 0, 2, 32, TRUE, 0, complain_overflow_signed,
100 bfd_elf_generic_reloc, "R_X86_64_GOTTPOFF", FALSE, 0xffffffff,
101 0xffffffff, TRUE),
102 HOWTO(R_X86_64_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
103 bfd_elf_generic_reloc, "R_X86_64_TPOFF32", FALSE, 0xffffffff,
104 0xffffffff, FALSE),
105
106 /* GNU extension to record C++ vtable hierarchy. */
107 HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, FALSE, 0, complain_overflow_dont,
108 NULL, "R_X86_64_GNU_VTINHERIT", FALSE, 0, 0, FALSE),
109
110 /* GNU extension to record C++ vtable member usage. */
111 HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, FALSE, 0, complain_overflow_dont,
112 _bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", FALSE, 0, 0,
113 FALSE)
114 };
115
116 /* Map BFD relocs to the x86_64 elf relocs. */
117 struct elf_reloc_map
118 {
119 bfd_reloc_code_real_type bfd_reloc_val;
120 unsigned char elf_reloc_val;
121 };
122
123 static const struct elf_reloc_map x86_64_reloc_map[] =
124 {
125 { BFD_RELOC_NONE, R_X86_64_NONE, },
126 { BFD_RELOC_64, R_X86_64_64, },
127 { BFD_RELOC_32_PCREL, R_X86_64_PC32, },
128 { BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,},
129 { BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,},
130 { BFD_RELOC_X86_64_COPY, R_X86_64_COPY, },
131 { BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, },
132 { BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, },
133 { BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, },
134 { BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, },
135 { BFD_RELOC_32, R_X86_64_32, },
136 { BFD_RELOC_X86_64_32S, R_X86_64_32S, },
137 { BFD_RELOC_16, R_X86_64_16, },
138 { BFD_RELOC_16_PCREL, R_X86_64_PC16, },
139 { BFD_RELOC_8, R_X86_64_8, },
140 { BFD_RELOC_8_PCREL, R_X86_64_PC8, },
141 { BFD_RELOC_X86_64_DTPMOD64, R_X86_64_DTPMOD64, },
142 { BFD_RELOC_X86_64_DTPOFF64, R_X86_64_DTPOFF64, },
143 { BFD_RELOC_X86_64_TPOFF64, R_X86_64_TPOFF64, },
144 { BFD_RELOC_X86_64_TLSGD, R_X86_64_TLSGD, },
145 { BFD_RELOC_X86_64_TLSLD, R_X86_64_TLSLD, },
146 { BFD_RELOC_X86_64_DTPOFF32, R_X86_64_DTPOFF32, },
147 { BFD_RELOC_X86_64_GOTTPOFF, R_X86_64_GOTTPOFF, },
148 { BFD_RELOC_X86_64_TPOFF32, R_X86_64_TPOFF32, },
149 { BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
150 { BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
151 };
152
153
154 /* Given a BFD reloc type, return a HOWTO structure. */
155 static reloc_howto_type *
156 elf64_x86_64_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
157 bfd_reloc_code_real_type code)
158 {
159 unsigned int i;
160
161 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
162 i++)
163 {
164 if (x86_64_reloc_map[i].bfd_reloc_val == code)
165 return &x86_64_elf_howto_table[i];
166 }
167 return 0;
168 }
169
170 /* Given an x86_64 ELF reloc type, fill in an arelent structure. */
171
172 static void
173 elf64_x86_64_info_to_howto (bfd *abfd ATTRIBUTE_UNUSED, arelent *cache_ptr,
174 Elf_Internal_Rela *dst)
175 {
176 unsigned r_type, i;
177
178 r_type = ELF64_R_TYPE (dst->r_info);
179 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT)
180 {
181 BFD_ASSERT (r_type <= (unsigned int) R_X86_64_TPOFF32);
182 i = r_type;
183 }
184 else
185 {
186 BFD_ASSERT (r_type < (unsigned int) R_X86_64_max);
187 i = r_type - ((unsigned int) R_X86_64_GNU_VTINHERIT - R_X86_64_TPOFF32 - 1);
188 }
189 cache_ptr->howto = &x86_64_elf_howto_table[i];
190 BFD_ASSERT (r_type == cache_ptr->howto->type);
191 }
192 \f
193 /* Support for core dump NOTE sections. */
194 static bfd_boolean
195 elf64_x86_64_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
196 {
197 int offset;
198 size_t raw_size;
199
200 switch (note->descsz)
201 {
202 default:
203 return FALSE;
204
205 case 336: /* sizeof(istruct elf_prstatus) on Linux/x86_64 */
206 /* pr_cursig */
207 elf_tdata (abfd)->core_signal
208 = bfd_get_16 (abfd, note->descdata + 12);
209
210 /* pr_pid */
211 elf_tdata (abfd)->core_pid
212 = bfd_get_32 (abfd, note->descdata + 32);
213
214 /* pr_reg */
215 offset = 112;
216 raw_size = 216;
217
218 break;
219 }
220
221 /* Make a ".reg/999" section. */
222 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
223 raw_size, note->descpos + offset);
224 }
225
226 static bfd_boolean
227 elf64_x86_64_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
228 {
229 switch (note->descsz)
230 {
231 default:
232 return FALSE;
233
234 case 136: /* sizeof(struct elf_prpsinfo) on Linux/x86_64 */
235 elf_tdata (abfd)->core_program
236 = _bfd_elfcore_strndup (abfd, note->descdata + 40, 16);
237 elf_tdata (abfd)->core_command
238 = _bfd_elfcore_strndup (abfd, note->descdata + 56, 80);
239 }
240
241 /* Note that for some reason, a spurious space is tacked
242 onto the end of the args in some (at least one anyway)
243 implementations, so strip it off if it exists. */
244
245 {
246 char *command = elf_tdata (abfd)->core_command;
247 int n = strlen (command);
248
249 if (0 < n && command[n - 1] == ' ')
250 command[n - 1] = '\0';
251 }
252
253 return TRUE;
254 }
255 \f
256 /* Functions for the x86-64 ELF linker. */
257
258 /* The name of the dynamic interpreter. This is put in the .interp
259 section. */
260
261 #define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
262
263 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
264 copying dynamic variables from a shared lib into an app's dynbss
265 section, and instead use a dynamic relocation to point into the
266 shared lib. */
267 #define ELIMINATE_COPY_RELOCS 1
268
269 /* The size in bytes of an entry in the global offset table. */
270
271 #define GOT_ENTRY_SIZE 8
272
273 /* The size in bytes of an entry in the procedure linkage table. */
274
275 #define PLT_ENTRY_SIZE 16
276
277 /* The first entry in a procedure linkage table looks like this. See the
278 SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
279
280 static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
281 {
282 0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
283 0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
284 0x90, 0x90, 0x90, 0x90 /* pad out to 16 bytes with nops. */
285 };
286
287 /* Subsequent entries in a procedure linkage table look like this. */
288
289 static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
290 {
291 0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
292 0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
293 0x68, /* pushq immediate */
294 0, 0, 0, 0, /* replaced with index into relocation table. */
295 0xe9, /* jmp relative */
296 0, 0, 0, 0 /* replaced with offset to start of .plt0. */
297 };
298
299 /* The x86-64 linker needs to keep track of the number of relocs that
300 it decides to copy as dynamic relocs in check_relocs for each symbol.
301 This is so that it can later discard them if they are found to be
302 unnecessary. We store the information in a field extending the
303 regular ELF linker hash table. */
304
305 struct elf64_x86_64_dyn_relocs
306 {
307 /* Next section. */
308 struct elf64_x86_64_dyn_relocs *next;
309
310 /* The input section of the reloc. */
311 asection *sec;
312
313 /* Total number of relocs copied for the input section. */
314 bfd_size_type count;
315
316 /* Number of pc-relative relocs copied for the input section. */
317 bfd_size_type pc_count;
318 };
319
320 /* x86-64 ELF linker hash entry. */
321
322 struct elf64_x86_64_link_hash_entry
323 {
324 struct elf_link_hash_entry elf;
325
326 /* Track dynamic relocs copied for this symbol. */
327 struct elf64_x86_64_dyn_relocs *dyn_relocs;
328
329 #define GOT_UNKNOWN 0
330 #define GOT_NORMAL 1
331 #define GOT_TLS_GD 2
332 #define GOT_TLS_IE 3
333 unsigned char tls_type;
334 };
335
336 #define elf64_x86_64_hash_entry(ent) \
337 ((struct elf64_x86_64_link_hash_entry *)(ent))
338
339 struct elf64_x86_64_obj_tdata
340 {
341 struct elf_obj_tdata root;
342
343 /* tls_type for each local got entry. */
344 char *local_got_tls_type;
345 };
346
347 #define elf64_x86_64_tdata(abfd) \
348 ((struct elf64_x86_64_obj_tdata *) (abfd)->tdata.any)
349
350 #define elf64_x86_64_local_got_tls_type(abfd) \
351 (elf64_x86_64_tdata (abfd)->local_got_tls_type)
352
353
354 /* x86-64 ELF linker hash table. */
355
356 struct elf64_x86_64_link_hash_table
357 {
358 struct elf_link_hash_table elf;
359
360 /* Short-cuts to get to dynamic linker sections. */
361 asection *sgot;
362 asection *sgotplt;
363 asection *srelgot;
364 asection *splt;
365 asection *srelplt;
366 asection *sdynbss;
367 asection *srelbss;
368
369 union {
370 bfd_signed_vma refcount;
371 bfd_vma offset;
372 } tls_ld_got;
373
374 /* Small local sym to section mapping cache. */
375 struct sym_sec_cache sym_sec;
376 };
377
378 /* Get the x86-64 ELF linker hash table from a link_info structure. */
379
380 #define elf64_x86_64_hash_table(p) \
381 ((struct elf64_x86_64_link_hash_table *) ((p)->hash))
382
383 /* Create an entry in an x86-64 ELF linker hash table. */
384
385 static struct bfd_hash_entry *
386 link_hash_newfunc (struct bfd_hash_entry *entry, struct bfd_hash_table *table,
387 const char *string)
388 {
389 /* Allocate the structure if it has not already been allocated by a
390 subclass. */
391 if (entry == NULL)
392 {
393 entry = bfd_hash_allocate (table,
394 sizeof (struct elf64_x86_64_link_hash_entry));
395 if (entry == NULL)
396 return entry;
397 }
398
399 /* Call the allocation method of the superclass. */
400 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
401 if (entry != NULL)
402 {
403 struct elf64_x86_64_link_hash_entry *eh;
404
405 eh = (struct elf64_x86_64_link_hash_entry *) entry;
406 eh->dyn_relocs = NULL;
407 eh->tls_type = GOT_UNKNOWN;
408 }
409
410 return entry;
411 }
412
413 /* Create an X86-64 ELF linker hash table. */
414
415 static struct bfd_link_hash_table *
416 elf64_x86_64_link_hash_table_create (bfd *abfd)
417 {
418 struct elf64_x86_64_link_hash_table *ret;
419 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table);
420
421 ret = (struct elf64_x86_64_link_hash_table *) bfd_malloc (amt);
422 if (ret == NULL)
423 return NULL;
424
425 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc))
426 {
427 free (ret);
428 return NULL;
429 }
430
431 ret->sgot = NULL;
432 ret->sgotplt = NULL;
433 ret->srelgot = NULL;
434 ret->splt = NULL;
435 ret->srelplt = NULL;
436 ret->sdynbss = NULL;
437 ret->srelbss = NULL;
438 ret->sym_sec.abfd = NULL;
439 ret->tls_ld_got.refcount = 0;
440
441 return &ret->elf.root;
442 }
443
444 /* Create .got, .gotplt, and .rela.got sections in DYNOBJ, and set up
445 shortcuts to them in our hash table. */
446
447 static bfd_boolean
448 create_got_section (bfd *dynobj, struct bfd_link_info *info)
449 {
450 struct elf64_x86_64_link_hash_table *htab;
451
452 if (! _bfd_elf_create_got_section (dynobj, info))
453 return FALSE;
454
455 htab = elf64_x86_64_hash_table (info);
456 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
457 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
458 if (!htab->sgot || !htab->sgotplt)
459 abort ();
460
461 htab->srelgot = bfd_make_section (dynobj, ".rela.got");
462 if (htab->srelgot == NULL
463 || ! bfd_set_section_flags (dynobj, htab->srelgot,
464 (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
465 | SEC_IN_MEMORY | SEC_LINKER_CREATED
466 | SEC_READONLY))
467 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 3))
468 return FALSE;
469 return TRUE;
470 }
471
472 /* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and
473 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our
474 hash table. */
475
476 static bfd_boolean
477 elf64_x86_64_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info)
478 {
479 struct elf64_x86_64_link_hash_table *htab;
480
481 htab = elf64_x86_64_hash_table (info);
482 if (!htab->sgot && !create_got_section (dynobj, info))
483 return FALSE;
484
485 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
486 return FALSE;
487
488 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
489 htab->srelplt = bfd_get_section_by_name (dynobj, ".rela.plt");
490 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
491 if (!info->shared)
492 htab->srelbss = bfd_get_section_by_name (dynobj, ".rela.bss");
493
494 if (!htab->splt || !htab->srelplt || !htab->sdynbss
495 || (!info->shared && !htab->srelbss))
496 abort ();
497
498 return TRUE;
499 }
500
501 /* Copy the extra info we tack onto an elf_link_hash_entry. */
502
503 static void
504 elf64_x86_64_copy_indirect_symbol (const struct elf_backend_data *bed,
505 struct elf_link_hash_entry *dir,
506 struct elf_link_hash_entry *ind)
507 {
508 struct elf64_x86_64_link_hash_entry *edir, *eind;
509
510 edir = (struct elf64_x86_64_link_hash_entry *) dir;
511 eind = (struct elf64_x86_64_link_hash_entry *) ind;
512
513 if (eind->dyn_relocs != NULL)
514 {
515 if (edir->dyn_relocs != NULL)
516 {
517 struct elf64_x86_64_dyn_relocs **pp;
518 struct elf64_x86_64_dyn_relocs *p;
519
520 if (ind->root.type == bfd_link_hash_indirect)
521 abort ();
522
523 /* Add reloc counts against the weak sym to the strong sym
524 list. Merge any entries against the same section. */
525 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
526 {
527 struct elf64_x86_64_dyn_relocs *q;
528
529 for (q = edir->dyn_relocs; q != NULL; q = q->next)
530 if (q->sec == p->sec)
531 {
532 q->pc_count += p->pc_count;
533 q->count += p->count;
534 *pp = p->next;
535 break;
536 }
537 if (q == NULL)
538 pp = &p->next;
539 }
540 *pp = edir->dyn_relocs;
541 }
542
543 edir->dyn_relocs = eind->dyn_relocs;
544 eind->dyn_relocs = NULL;
545 }
546
547 if (ind->root.type == bfd_link_hash_indirect
548 && dir->got.refcount <= 0)
549 {
550 edir->tls_type = eind->tls_type;
551 eind->tls_type = GOT_UNKNOWN;
552 }
553
554 if (ELIMINATE_COPY_RELOCS
555 && ind->root.type != bfd_link_hash_indirect
556 && (dir->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
557 /* If called to transfer flags for a weakdef during processing
558 of elf_adjust_dynamic_symbol, don't copy ELF_LINK_NON_GOT_REF.
559 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
560 dir->elf_link_hash_flags |=
561 (ind->elf_link_hash_flags & (ELF_LINK_HASH_REF_DYNAMIC
562 | ELF_LINK_HASH_REF_REGULAR
563 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
564 | ELF_LINK_HASH_NEEDS_PLT
565 | ELF_LINK_POINTER_EQUALITY_NEEDED));
566 else
567 _bfd_elf_link_hash_copy_indirect (bed, dir, ind);
568 }
569
570 static bfd_boolean
571 elf64_x86_64_mkobject (bfd *abfd)
572 {
573 bfd_size_type amt = sizeof (struct elf64_x86_64_obj_tdata);
574 abfd->tdata.any = bfd_zalloc (abfd, amt);
575 if (abfd->tdata.any == NULL)
576 return FALSE;
577 return TRUE;
578 }
579
580 static bfd_boolean
581 elf64_x86_64_elf_object_p (bfd *abfd)
582 {
583 /* Set the right machine number for an x86-64 elf64 file. */
584 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
585 return TRUE;
586 }
587
588 static int
589 elf64_x86_64_tls_transition (struct bfd_link_info *info, int r_type, int is_local)
590 {
591 if (info->shared)
592 return r_type;
593
594 switch (r_type)
595 {
596 case R_X86_64_TLSGD:
597 case R_X86_64_GOTTPOFF:
598 if (is_local)
599 return R_X86_64_TPOFF32;
600 return R_X86_64_GOTTPOFF;
601 case R_X86_64_TLSLD:
602 return R_X86_64_TPOFF32;
603 }
604
605 return r_type;
606 }
607
608 /* Look through the relocs for a section during the first phase, and
609 calculate needed space in the global offset table, procedure
610 linkage table, and dynamic reloc sections. */
611
612 static bfd_boolean
613 elf64_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info, asection *sec,
614 const Elf_Internal_Rela *relocs)
615 {
616 struct elf64_x86_64_link_hash_table *htab;
617 Elf_Internal_Shdr *symtab_hdr;
618 struct elf_link_hash_entry **sym_hashes;
619 const Elf_Internal_Rela *rel;
620 const Elf_Internal_Rela *rel_end;
621 asection *sreloc;
622
623 if (info->relocatable)
624 return TRUE;
625
626 htab = elf64_x86_64_hash_table (info);
627 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
628 sym_hashes = elf_sym_hashes (abfd);
629
630 sreloc = NULL;
631
632 rel_end = relocs + sec->reloc_count;
633 for (rel = relocs; rel < rel_end; rel++)
634 {
635 unsigned int r_type;
636 unsigned long r_symndx;
637 struct elf_link_hash_entry *h;
638
639 r_symndx = ELF64_R_SYM (rel->r_info);
640 r_type = ELF64_R_TYPE (rel->r_info);
641
642 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
643 {
644 (*_bfd_error_handler) (_("%s: bad symbol index: %d"),
645 bfd_archive_filename (abfd),
646 r_symndx);
647 return FALSE;
648 }
649
650 if (r_symndx < symtab_hdr->sh_info)
651 h = NULL;
652 else
653 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
654
655 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
656 switch (r_type)
657 {
658 case R_X86_64_TLSLD:
659 htab->tls_ld_got.refcount += 1;
660 goto create_got;
661
662 case R_X86_64_TPOFF32:
663 if (info->shared)
664 {
665 (*_bfd_error_handler)
666 (_("%s: relocation %s can not be used when making a shared object; recompile with -fPIC"),
667 bfd_archive_filename (abfd),
668 x86_64_elf_howto_table[r_type].name);
669 bfd_set_error (bfd_error_bad_value);
670 return FALSE;
671 }
672 break;
673
674 case R_X86_64_GOTTPOFF:
675 if (info->shared)
676 info->flags |= DF_STATIC_TLS;
677 /* Fall through */
678
679 case R_X86_64_GOT32:
680 case R_X86_64_GOTPCREL:
681 case R_X86_64_TLSGD:
682 /* This symbol requires a global offset table entry. */
683 {
684 int tls_type, old_tls_type;
685
686 switch (r_type)
687 {
688 default: tls_type = GOT_NORMAL; break;
689 case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
690 case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
691 }
692
693 if (h != NULL)
694 {
695 h->got.refcount += 1;
696 old_tls_type = elf64_x86_64_hash_entry (h)->tls_type;
697 }
698 else
699 {
700 bfd_signed_vma *local_got_refcounts;
701
702 /* This is a global offset table entry for a local symbol. */
703 local_got_refcounts = elf_local_got_refcounts (abfd);
704 if (local_got_refcounts == NULL)
705 {
706 bfd_size_type size;
707
708 size = symtab_hdr->sh_info;
709 size *= sizeof (bfd_signed_vma) + sizeof (char);
710 local_got_refcounts = ((bfd_signed_vma *)
711 bfd_zalloc (abfd, size));
712 if (local_got_refcounts == NULL)
713 return FALSE;
714 elf_local_got_refcounts (abfd) = local_got_refcounts;
715 elf64_x86_64_local_got_tls_type (abfd)
716 = (char *) (local_got_refcounts + symtab_hdr->sh_info);
717 }
718 local_got_refcounts[r_symndx] += 1;
719 old_tls_type
720 = elf64_x86_64_local_got_tls_type (abfd) [r_symndx];
721 }
722
723 /* If a TLS symbol is accessed using IE at least once,
724 there is no point to use dynamic model for it. */
725 if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
726 && (old_tls_type != GOT_TLS_GD || tls_type != GOT_TLS_IE))
727 {
728 if (old_tls_type == GOT_TLS_IE && tls_type == GOT_TLS_GD)
729 tls_type = old_tls_type;
730 else
731 {
732 (*_bfd_error_handler)
733 (_("%s: %s' accessed both as normal and thread local symbol"),
734 bfd_archive_filename (abfd),
735 h ? h->root.root.string : "<local>");
736 return FALSE;
737 }
738 }
739
740 if (old_tls_type != tls_type)
741 {
742 if (h != NULL)
743 elf64_x86_64_hash_entry (h)->tls_type = tls_type;
744 else
745 elf64_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
746 }
747 }
748 /* Fall through */
749
750 //case R_X86_64_GOTPCREL:
751 create_got:
752 if (htab->sgot == NULL)
753 {
754 if (htab->elf.dynobj == NULL)
755 htab->elf.dynobj = abfd;
756 if (!create_got_section (htab->elf.dynobj, info))
757 return FALSE;
758 }
759 break;
760
761 case R_X86_64_PLT32:
762 /* This symbol requires a procedure linkage table entry. We
763 actually build the entry in adjust_dynamic_symbol,
764 because this might be a case of linking PIC code which is
765 never referenced by a dynamic object, in which case we
766 don't need to generate a procedure linkage table entry
767 after all. */
768
769 /* If this is a local symbol, we resolve it directly without
770 creating a procedure linkage table entry. */
771 if (h == NULL)
772 continue;
773
774 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
775 h->plt.refcount += 1;
776 break;
777
778 case R_X86_64_8:
779 case R_X86_64_16:
780 case R_X86_64_32:
781 case R_X86_64_32S:
782 /* Let's help debug shared library creation. These relocs
783 cannot be used in shared libs. Don't error out for
784 sections we don't care about, such as debug sections or
785 non-constant sections. */
786 if (info->shared
787 && (sec->flags & SEC_ALLOC) != 0
788 && (sec->flags & SEC_READONLY) != 0)
789 {
790 (*_bfd_error_handler)
791 (_("%s: relocation %s can not be used when making a shared object; recompile with -fPIC"),
792 bfd_archive_filename (abfd),
793 x86_64_elf_howto_table[r_type].name);
794 bfd_set_error (bfd_error_bad_value);
795 return FALSE;
796 }
797 /* Fall through. */
798
799 case R_X86_64_PC8:
800 case R_X86_64_PC16:
801 case R_X86_64_PC32:
802 case R_X86_64_64:
803 if (h != NULL && !info->shared)
804 {
805 /* If this reloc is in a read-only section, we might
806 need a copy reloc. We can't check reliably at this
807 stage whether the section is read-only, as input
808 sections have not yet been mapped to output sections.
809 Tentatively set the flag for now, and correct in
810 adjust_dynamic_symbol. */
811 h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF;
812
813 /* We may need a .plt entry if the function this reloc
814 refers to is in a shared lib. */
815 h->plt.refcount += 1;
816 if (r_type != R_X86_64_PC32)
817 h->elf_link_hash_flags |= ELF_LINK_POINTER_EQUALITY_NEEDED;
818 }
819
820 /* If we are creating a shared library, and this is a reloc
821 against a global symbol, or a non PC relative reloc
822 against a local symbol, then we need to copy the reloc
823 into the shared library. However, if we are linking with
824 -Bsymbolic, we do not need to copy a reloc against a
825 global symbol which is defined in an object we are
826 including in the link (i.e., DEF_REGULAR is set). At
827 this point we have not seen all the input files, so it is
828 possible that DEF_REGULAR is not set now but will be set
829 later (it is never cleared). In case of a weak definition,
830 DEF_REGULAR may be cleared later by a strong definition in
831 a shared library. We account for that possibility below by
832 storing information in the relocs_copied field of the hash
833 table entry. A similar situation occurs when creating
834 shared libraries and symbol visibility changes render the
835 symbol local.
836
837 If on the other hand, we are creating an executable, we
838 may need to keep relocations for symbols satisfied by a
839 dynamic library if we manage to avoid copy relocs for the
840 symbol. */
841 if ((info->shared
842 && (sec->flags & SEC_ALLOC) != 0
843 && (((r_type != R_X86_64_PC8)
844 && (r_type != R_X86_64_PC16)
845 && (r_type != R_X86_64_PC32))
846 || (h != NULL
847 && (! info->symbolic
848 || h->root.type == bfd_link_hash_defweak
849 || (h->elf_link_hash_flags
850 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
851 || (ELIMINATE_COPY_RELOCS
852 && !info->shared
853 && (sec->flags & SEC_ALLOC) != 0
854 && h != NULL
855 && (h->root.type == bfd_link_hash_defweak
856 || (h->elf_link_hash_flags
857 & ELF_LINK_HASH_DEF_REGULAR) == 0)))
858 {
859 struct elf64_x86_64_dyn_relocs *p;
860 struct elf64_x86_64_dyn_relocs **head;
861
862 /* We must copy these reloc types into the output file.
863 Create a reloc section in dynobj and make room for
864 this reloc. */
865 if (sreloc == NULL)
866 {
867 const char *name;
868 bfd *dynobj;
869
870 name = (bfd_elf_string_from_elf_section
871 (abfd,
872 elf_elfheader (abfd)->e_shstrndx,
873 elf_section_data (sec)->rel_hdr.sh_name));
874 if (name == NULL)
875 return FALSE;
876
877 if (strncmp (name, ".rela", 5) != 0
878 || strcmp (bfd_get_section_name (abfd, sec),
879 name + 5) != 0)
880 {
881 (*_bfd_error_handler)
882 (_("%s: bad relocation section name `%s\'"),
883 bfd_archive_filename (abfd), name);
884 }
885
886 if (htab->elf.dynobj == NULL)
887 htab->elf.dynobj = abfd;
888
889 dynobj = htab->elf.dynobj;
890
891 sreloc = bfd_get_section_by_name (dynobj, name);
892 if (sreloc == NULL)
893 {
894 flagword flags;
895
896 sreloc = bfd_make_section (dynobj, name);
897 flags = (SEC_HAS_CONTENTS | SEC_READONLY
898 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
899 if ((sec->flags & SEC_ALLOC) != 0)
900 flags |= SEC_ALLOC | SEC_LOAD;
901 if (sreloc == NULL
902 || ! bfd_set_section_flags (dynobj, sreloc, flags)
903 || ! bfd_set_section_alignment (dynobj, sreloc, 3))
904 return FALSE;
905 }
906 elf_section_data (sec)->sreloc = sreloc;
907 }
908
909 /* If this is a global symbol, we count the number of
910 relocations we need for this symbol. */
911 if (h != NULL)
912 {
913 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs;
914 }
915 else
916 {
917 /* Track dynamic relocs needed for local syms too.
918 We really need local syms available to do this
919 easily. Oh well. */
920
921 asection *s;
922 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
923 sec, r_symndx);
924 if (s == NULL)
925 return FALSE;
926
927 head = ((struct elf64_x86_64_dyn_relocs **)
928 &elf_section_data (s)->local_dynrel);
929 }
930
931 p = *head;
932 if (p == NULL || p->sec != sec)
933 {
934 bfd_size_type amt = sizeof *p;
935 p = ((struct elf64_x86_64_dyn_relocs *)
936 bfd_alloc (htab->elf.dynobj, amt));
937 if (p == NULL)
938 return FALSE;
939 p->next = *head;
940 *head = p;
941 p->sec = sec;
942 p->count = 0;
943 p->pc_count = 0;
944 }
945
946 p->count += 1;
947 if (r_type == R_X86_64_PC8
948 || r_type == R_X86_64_PC16
949 || r_type == R_X86_64_PC32)
950 p->pc_count += 1;
951 }
952 break;
953
954 /* This relocation describes the C++ object vtable hierarchy.
955 Reconstruct it for later use during GC. */
956 case R_X86_64_GNU_VTINHERIT:
957 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
958 return FALSE;
959 break;
960
961 /* This relocation describes which C++ vtable entries are actually
962 used. Record for later use during GC. */
963 case R_X86_64_GNU_VTENTRY:
964 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
965 return FALSE;
966 break;
967
968 default:
969 break;
970 }
971 }
972
973 return TRUE;
974 }
975
976 /* Return the section that should be marked against GC for a given
977 relocation. */
978
979 static asection *
980 elf64_x86_64_gc_mark_hook (asection *sec,
981 struct bfd_link_info *info ATTRIBUTE_UNUSED,
982 Elf_Internal_Rela *rel,
983 struct elf_link_hash_entry *h,
984 Elf_Internal_Sym *sym)
985 {
986 if (h != NULL)
987 {
988 switch (ELF64_R_TYPE (rel->r_info))
989 {
990 case R_X86_64_GNU_VTINHERIT:
991 case R_X86_64_GNU_VTENTRY:
992 break;
993
994 default:
995 switch (h->root.type)
996 {
997 case bfd_link_hash_defined:
998 case bfd_link_hash_defweak:
999 return h->root.u.def.section;
1000
1001 case bfd_link_hash_common:
1002 return h->root.u.c.p->section;
1003
1004 default:
1005 break;
1006 }
1007 }
1008 }
1009 else
1010 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
1011
1012 return NULL;
1013 }
1014
1015 /* Update the got entry reference counts for the section being removed. */
1016
1017 static bfd_boolean
1018 elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
1019 asection *sec, const Elf_Internal_Rela *relocs)
1020 {
1021 Elf_Internal_Shdr *symtab_hdr;
1022 struct elf_link_hash_entry **sym_hashes;
1023 bfd_signed_vma *local_got_refcounts;
1024 const Elf_Internal_Rela *rel, *relend;
1025
1026 elf_section_data (sec)->local_dynrel = NULL;
1027
1028 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1029 sym_hashes = elf_sym_hashes (abfd);
1030 local_got_refcounts = elf_local_got_refcounts (abfd);
1031
1032 relend = relocs + sec->reloc_count;
1033 for (rel = relocs; rel < relend; rel++)
1034 {
1035 unsigned long r_symndx;
1036 unsigned int r_type;
1037 struct elf_link_hash_entry *h = NULL;
1038
1039 r_symndx = ELF64_R_SYM (rel->r_info);
1040 if (r_symndx >= symtab_hdr->sh_info)
1041 {
1042 struct elf64_x86_64_link_hash_entry *eh;
1043 struct elf64_x86_64_dyn_relocs **pp;
1044 struct elf64_x86_64_dyn_relocs *p;
1045
1046 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1047 eh = (struct elf64_x86_64_link_hash_entry *) h;
1048
1049 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1050 if (p->sec == sec)
1051 {
1052 /* Everything must go for SEC. */
1053 *pp = p->next;
1054 break;
1055 }
1056 }
1057
1058 r_type = ELF64_R_TYPE (rel->r_info);
1059 r_type = elf64_x86_64_tls_transition (info, r_type, h != NULL);
1060 switch (r_type)
1061 {
1062 case R_X86_64_TLSLD:
1063 if (elf64_x86_64_hash_table (info)->tls_ld_got.refcount > 0)
1064 elf64_x86_64_hash_table (info)->tls_ld_got.refcount -= 1;
1065 break;
1066
1067 case R_X86_64_TLSGD:
1068 case R_X86_64_GOTTPOFF:
1069 case R_X86_64_GOT32:
1070 case R_X86_64_GOTPCREL:
1071 if (h != NULL)
1072 {
1073 if (h->got.refcount > 0)
1074 h->got.refcount -= 1;
1075 }
1076 else if (local_got_refcounts != NULL)
1077 {
1078 if (local_got_refcounts[r_symndx] > 0)
1079 local_got_refcounts[r_symndx] -= 1;
1080 }
1081 break;
1082
1083 case R_X86_64_8:
1084 case R_X86_64_16:
1085 case R_X86_64_32:
1086 case R_X86_64_64:
1087 case R_X86_64_32S:
1088 case R_X86_64_PC8:
1089 case R_X86_64_PC16:
1090 case R_X86_64_PC32:
1091 if (info->shared)
1092 break;
1093 /* Fall thru */
1094
1095 case R_X86_64_PLT32:
1096 if (h != NULL)
1097 {
1098 if (h->plt.refcount > 0)
1099 h->plt.refcount -= 1;
1100 }
1101 break;
1102
1103 default:
1104 break;
1105 }
1106 }
1107
1108 return TRUE;
1109 }
1110
1111 /* Adjust a symbol defined by a dynamic object and referenced by a
1112 regular object. The current definition is in some section of the
1113 dynamic object, but we're not including those sections. We have to
1114 change the definition to something the rest of the link can
1115 understand. */
1116
1117 static bfd_boolean
1118 elf64_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
1119 struct elf_link_hash_entry *h)
1120 {
1121 struct elf64_x86_64_link_hash_table *htab;
1122 asection *s;
1123 unsigned int power_of_two;
1124
1125 /* If this is a function, put it in the procedure linkage table. We
1126 will fill in the contents of the procedure linkage table later,
1127 when we know the address of the .got section. */
1128 if (h->type == STT_FUNC
1129 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
1130 {
1131 if (h->plt.refcount <= 0
1132 || SYMBOL_CALLS_LOCAL (info, h)
1133 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1134 && h->root.type == bfd_link_hash_undefweak))
1135 {
1136 /* This case can occur if we saw a PLT32 reloc in an input
1137 file, but the symbol was never referred to by a dynamic
1138 object, or if all references were garbage collected. In
1139 such a case, we don't actually need to build a procedure
1140 linkage table, and we can just do a PC32 reloc instead. */
1141 h->plt.offset = (bfd_vma) -1;
1142 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1143 }
1144
1145 return TRUE;
1146 }
1147 else
1148 /* It's possible that we incorrectly decided a .plt reloc was
1149 needed for an R_X86_64_PC32 reloc to a non-function sym in
1150 check_relocs. We can't decide accurately between function and
1151 non-function syms in check-relocs; Objects loaded later in
1152 the link may change h->type. So fix it now. */
1153 h->plt.offset = (bfd_vma) -1;
1154
1155 /* If this is a weak symbol, and there is a real definition, the
1156 processor independent code will have arranged for us to see the
1157 real definition first, and we can just use the same value. */
1158 if (h->weakdef != NULL)
1159 {
1160 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
1161 || h->weakdef->root.type == bfd_link_hash_defweak);
1162 h->root.u.def.section = h->weakdef->root.u.def.section;
1163 h->root.u.def.value = h->weakdef->root.u.def.value;
1164 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1165 h->elf_link_hash_flags
1166 = ((h->elf_link_hash_flags & ~ELF_LINK_NON_GOT_REF)
1167 | (h->weakdef->elf_link_hash_flags & ELF_LINK_NON_GOT_REF));
1168 return TRUE;
1169 }
1170
1171 /* This is a reference to a symbol defined by a dynamic object which
1172 is not a function. */
1173
1174 /* If we are creating a shared library, we must presume that the
1175 only references to the symbol are via the global offset table.
1176 For such cases we need not do anything here; the relocations will
1177 be handled correctly by relocate_section. */
1178 if (info->shared)
1179 return TRUE;
1180
1181 /* If there are no references to this symbol that do not use the
1182 GOT, we don't need to generate a copy reloc. */
1183 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0)
1184 return TRUE;
1185
1186 /* If -z nocopyreloc was given, we won't generate them either. */
1187 if (info->nocopyreloc)
1188 {
1189 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1190 return TRUE;
1191 }
1192
1193 if (ELIMINATE_COPY_RELOCS)
1194 {
1195 struct elf64_x86_64_link_hash_entry * eh;
1196 struct elf64_x86_64_dyn_relocs *p;
1197
1198 eh = (struct elf64_x86_64_link_hash_entry *) h;
1199 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1200 {
1201 s = p->sec->output_section;
1202 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1203 break;
1204 }
1205
1206 /* If we didn't find any dynamic relocs in read-only sections, then
1207 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1208 if (p == NULL)
1209 {
1210 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1211 return TRUE;
1212 }
1213 }
1214
1215 /* We must allocate the symbol in our .dynbss section, which will
1216 become part of the .bss section of the executable. There will be
1217 an entry for this symbol in the .dynsym section. The dynamic
1218 object will contain position independent code, so all references
1219 from the dynamic object to this symbol will go through the global
1220 offset table. The dynamic linker will use the .dynsym entry to
1221 determine the address it must put in the global offset table, so
1222 both the dynamic object and the regular object will refer to the
1223 same memory location for the variable. */
1224
1225 htab = elf64_x86_64_hash_table (info);
1226
1227 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
1228 to copy the initial value out of the dynamic object and into the
1229 runtime process image. */
1230 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1231 {
1232 htab->srelbss->_raw_size += sizeof (Elf64_External_Rela);
1233 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
1234 }
1235
1236 /* We need to figure out the alignment required for this symbol. I
1237 have no idea how ELF linkers handle this. 16-bytes is the size
1238 of the largest type that requires hard alignment -- long double. */
1239 /* FIXME: This is VERY ugly. Should be fixed for all architectures using
1240 this construct. */
1241 power_of_two = bfd_log2 (h->size);
1242 if (power_of_two > 4)
1243 power_of_two = 4;
1244
1245 /* Apply the required alignment. */
1246 s = htab->sdynbss;
1247 s->_raw_size = BFD_ALIGN (s->_raw_size, (bfd_size_type) (1 << power_of_two));
1248 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1249 {
1250 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1251 return FALSE;
1252 }
1253
1254 /* Define the symbol as being at this point in the section. */
1255 h->root.u.def.section = s;
1256 h->root.u.def.value = s->_raw_size;
1257
1258 /* Increment the section size to make room for the symbol. */
1259 s->_raw_size += h->size;
1260
1261 return TRUE;
1262 }
1263
1264 /* Allocate space in .plt, .got and associated reloc sections for
1265 dynamic relocs. */
1266
1267 static bfd_boolean
1268 allocate_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1269 {
1270 struct bfd_link_info *info;
1271 struct elf64_x86_64_link_hash_table *htab;
1272 struct elf64_x86_64_link_hash_entry *eh;
1273 struct elf64_x86_64_dyn_relocs *p;
1274
1275 if (h->root.type == bfd_link_hash_indirect)
1276 return TRUE;
1277
1278 if (h->root.type == bfd_link_hash_warning)
1279 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1280
1281 info = (struct bfd_link_info *) inf;
1282 htab = elf64_x86_64_hash_table (info);
1283
1284 if (htab->elf.dynamic_sections_created
1285 && h->plt.refcount > 0)
1286 {
1287 /* Make sure this symbol is output as a dynamic symbol.
1288 Undefined weak syms won't yet be marked as dynamic. */
1289 if (h->dynindx == -1
1290 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1291 {
1292 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1293 return FALSE;
1294 }
1295
1296 if (info->shared
1297 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
1298 {
1299 asection *s = htab->splt;
1300
1301 /* If this is the first .plt entry, make room for the special
1302 first entry. */
1303 if (s->_raw_size == 0)
1304 s->_raw_size += PLT_ENTRY_SIZE;
1305
1306 h->plt.offset = s->_raw_size;
1307
1308 /* If this symbol is not defined in a regular file, and we are
1309 not generating a shared library, then set the symbol to this
1310 location in the .plt. This is required to make function
1311 pointers compare as equal between the normal executable and
1312 the shared library. */
1313 if (! info->shared
1314 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1315 {
1316 h->root.u.def.section = s;
1317 h->root.u.def.value = h->plt.offset;
1318 }
1319
1320 /* Make room for this entry. */
1321 s->_raw_size += PLT_ENTRY_SIZE;
1322
1323 /* We also need to make an entry in the .got.plt section, which
1324 will be placed in the .got section by the linker script. */
1325 htab->sgotplt->_raw_size += GOT_ENTRY_SIZE;
1326
1327 /* We also need to make an entry in the .rela.plt section. */
1328 htab->srelplt->_raw_size += sizeof (Elf64_External_Rela);
1329 }
1330 else
1331 {
1332 h->plt.offset = (bfd_vma) -1;
1333 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1334 }
1335 }
1336 else
1337 {
1338 h->plt.offset = (bfd_vma) -1;
1339 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1340 }
1341
1342 /* If R_X86_64_GOTTPOFF symbol is now local to the binary,
1343 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
1344 if (h->got.refcount > 0
1345 && !info->shared
1346 && h->dynindx == -1
1347 && elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
1348 h->got.offset = (bfd_vma) -1;
1349 else if (h->got.refcount > 0)
1350 {
1351 asection *s;
1352 bfd_boolean dyn;
1353 int tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1354
1355 /* Make sure this symbol is output as a dynamic symbol.
1356 Undefined weak syms won't yet be marked as dynamic. */
1357 if (h->dynindx == -1
1358 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1359 {
1360 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1361 return FALSE;
1362 }
1363
1364 s = htab->sgot;
1365 h->got.offset = s->_raw_size;
1366 s->_raw_size += GOT_ENTRY_SIZE;
1367 /* R_X86_64_TLSGD needs 2 consecutive GOT slots. */
1368 if (tls_type == GOT_TLS_GD)
1369 s->_raw_size += GOT_ENTRY_SIZE;
1370 dyn = htab->elf.dynamic_sections_created;
1371 /* R_X86_64_TLSGD needs one dynamic relocation if local symbol
1372 and two if global.
1373 R_X86_64_GOTTPOFF needs one dynamic relocation. */
1374 if ((tls_type == GOT_TLS_GD && h->dynindx == -1)
1375 || tls_type == GOT_TLS_IE)
1376 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1377 else if (tls_type == GOT_TLS_GD)
1378 htab->srelgot->_raw_size += 2 * sizeof (Elf64_External_Rela);
1379 else if ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1380 || h->root.type != bfd_link_hash_undefweak)
1381 && (info->shared
1382 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
1383 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1384 }
1385 else
1386 h->got.offset = (bfd_vma) -1;
1387
1388 eh = (struct elf64_x86_64_link_hash_entry *) h;
1389 if (eh->dyn_relocs == NULL)
1390 return TRUE;
1391
1392 /* In the shared -Bsymbolic case, discard space allocated for
1393 dynamic pc-relative relocs against symbols which turn out to be
1394 defined in regular objects. For the normal shared case, discard
1395 space for pc-relative relocs that have become local due to symbol
1396 visibility changes. */
1397
1398 if (info->shared)
1399 {
1400 /* Relocs that use pc_count are those that appear on a call
1401 insn, or certain REL relocs that can generated via assembly.
1402 We want calls to protected symbols to resolve directly to the
1403 function rather than going via the plt. If people want
1404 function pointer comparisons to work as expected then they
1405 should avoid writing weird assembly. */
1406 if (SYMBOL_CALLS_LOCAL (info, h))
1407 {
1408 struct elf64_x86_64_dyn_relocs **pp;
1409
1410 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1411 {
1412 p->count -= p->pc_count;
1413 p->pc_count = 0;
1414 if (p->count == 0)
1415 *pp = p->next;
1416 else
1417 pp = &p->next;
1418 }
1419 }
1420
1421 /* Also discard relocs on undefined weak syms with non-default
1422 visibility. */
1423 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1424 && h->root.type == bfd_link_hash_undefweak)
1425 eh->dyn_relocs = NULL;
1426 }
1427 else if (ELIMINATE_COPY_RELOCS)
1428 {
1429 /* For the non-shared case, discard space for relocs against
1430 symbols which turn out to need copy relocs or are not
1431 dynamic. */
1432
1433 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1434 && (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1435 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1436 || (htab->elf.dynamic_sections_created
1437 && (h->root.type == bfd_link_hash_undefweak
1438 || h->root.type == bfd_link_hash_undefined))))
1439 {
1440 /* Make sure this symbol is output as a dynamic symbol.
1441 Undefined weak syms won't yet be marked as dynamic. */
1442 if (h->dynindx == -1
1443 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1444 {
1445 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1446 return FALSE;
1447 }
1448
1449 /* If that succeeded, we know we'll be keeping all the
1450 relocs. */
1451 if (h->dynindx != -1)
1452 goto keep;
1453 }
1454
1455 eh->dyn_relocs = NULL;
1456
1457 keep: ;
1458 }
1459
1460 /* Finally, allocate space. */
1461 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1462 {
1463 asection *sreloc = elf_section_data (p->sec)->sreloc;
1464 sreloc->_raw_size += p->count * sizeof (Elf64_External_Rela);
1465 }
1466
1467 return TRUE;
1468 }
1469
1470 /* Find any dynamic relocs that apply to read-only sections. */
1471
1472 static bfd_boolean
1473 readonly_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1474 {
1475 struct elf64_x86_64_link_hash_entry *eh;
1476 struct elf64_x86_64_dyn_relocs *p;
1477
1478 if (h->root.type == bfd_link_hash_warning)
1479 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1480
1481 eh = (struct elf64_x86_64_link_hash_entry *) h;
1482 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1483 {
1484 asection *s = p->sec->output_section;
1485
1486 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1487 {
1488 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1489
1490 info->flags |= DF_TEXTREL;
1491
1492 /* Not an error, just cut short the traversal. */
1493 return FALSE;
1494 }
1495 }
1496 return TRUE;
1497 }
1498
1499 /* Set the sizes of the dynamic sections. */
1500
1501 static bfd_boolean
1502 elf64_x86_64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
1503 struct bfd_link_info *info)
1504 {
1505 struct elf64_x86_64_link_hash_table *htab;
1506 bfd *dynobj;
1507 asection *s;
1508 bfd_boolean relocs;
1509 bfd *ibfd;
1510
1511 htab = elf64_x86_64_hash_table (info);
1512 dynobj = htab->elf.dynobj;
1513 if (dynobj == NULL)
1514 abort ();
1515
1516 if (htab->elf.dynamic_sections_created)
1517 {
1518 /* Set the contents of the .interp section to the interpreter. */
1519 if (info->executable)
1520 {
1521 s = bfd_get_section_by_name (dynobj, ".interp");
1522 if (s == NULL)
1523 abort ();
1524 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
1525 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1526 }
1527 }
1528
1529 /* Set up .got offsets for local syms, and space for local dynamic
1530 relocs. */
1531 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1532 {
1533 bfd_signed_vma *local_got;
1534 bfd_signed_vma *end_local_got;
1535 char *local_tls_type;
1536 bfd_size_type locsymcount;
1537 Elf_Internal_Shdr *symtab_hdr;
1538 asection *srel;
1539
1540 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1541 continue;
1542
1543 for (s = ibfd->sections; s != NULL; s = s->next)
1544 {
1545 struct elf64_x86_64_dyn_relocs *p;
1546
1547 for (p = *((struct elf64_x86_64_dyn_relocs **)
1548 &elf_section_data (s)->local_dynrel);
1549 p != NULL;
1550 p = p->next)
1551 {
1552 if (!bfd_is_abs_section (p->sec)
1553 && bfd_is_abs_section (p->sec->output_section))
1554 {
1555 /* Input section has been discarded, either because
1556 it is a copy of a linkonce section or due to
1557 linker script /DISCARD/, so we'll be discarding
1558 the relocs too. */
1559 }
1560 else if (p->count != 0)
1561 {
1562 srel = elf_section_data (p->sec)->sreloc;
1563 srel->_raw_size += p->count * sizeof (Elf64_External_Rela);
1564 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1565 info->flags |= DF_TEXTREL;
1566
1567 }
1568 }
1569 }
1570
1571 local_got = elf_local_got_refcounts (ibfd);
1572 if (!local_got)
1573 continue;
1574
1575 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1576 locsymcount = symtab_hdr->sh_info;
1577 end_local_got = local_got + locsymcount;
1578 local_tls_type = elf64_x86_64_local_got_tls_type (ibfd);
1579 s = htab->sgot;
1580 srel = htab->srelgot;
1581 for (; local_got < end_local_got; ++local_got, ++local_tls_type)
1582 {
1583 if (*local_got > 0)
1584 {
1585 *local_got = s->_raw_size;
1586 s->_raw_size += GOT_ENTRY_SIZE;
1587 if (*local_tls_type == GOT_TLS_GD)
1588 s->_raw_size += GOT_ENTRY_SIZE;
1589 if (info->shared
1590 || *local_tls_type == GOT_TLS_GD
1591 || *local_tls_type == GOT_TLS_IE)
1592 srel->_raw_size += sizeof (Elf64_External_Rela);
1593 }
1594 else
1595 *local_got = (bfd_vma) -1;
1596 }
1597 }
1598
1599 if (htab->tls_ld_got.refcount > 0)
1600 {
1601 /* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD
1602 relocs. */
1603 htab->tls_ld_got.offset = htab->sgot->_raw_size;
1604 htab->sgot->_raw_size += 2 * GOT_ENTRY_SIZE;
1605 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1606 }
1607 else
1608 htab->tls_ld_got.offset = -1;
1609
1610 /* Allocate global sym .plt and .got entries, and space for global
1611 sym dynamic relocs. */
1612 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1613
1614 /* We now have determined the sizes of the various dynamic sections.
1615 Allocate memory for them. */
1616 relocs = FALSE;
1617 for (s = dynobj->sections; s != NULL; s = s->next)
1618 {
1619 if ((s->flags & SEC_LINKER_CREATED) == 0)
1620 continue;
1621
1622 if (s == htab->splt
1623 || s == htab->sgot
1624 || s == htab->sgotplt)
1625 {
1626 /* Strip this section if we don't need it; see the
1627 comment below. */
1628 }
1629 else if (strncmp (bfd_get_section_name (dynobj, s), ".rela", 5) == 0)
1630 {
1631 if (s->_raw_size != 0 && s != htab->srelplt)
1632 relocs = TRUE;
1633
1634 /* We use the reloc_count field as a counter if we need
1635 to copy relocs into the output file. */
1636 s->reloc_count = 0;
1637 }
1638 else
1639 {
1640 /* It's not one of our sections, so don't allocate space. */
1641 continue;
1642 }
1643
1644 if (s->_raw_size == 0)
1645 {
1646 /* If we don't need this section, strip it from the
1647 output file. This is mostly to handle .rela.bss and
1648 .rela.plt. We must create both sections in
1649 create_dynamic_sections, because they must be created
1650 before the linker maps input sections to output
1651 sections. The linker does that before
1652 adjust_dynamic_symbol is called, and it is that
1653 function which decides whether anything needs to go
1654 into these sections. */
1655
1656 _bfd_strip_section_from_output (info, s);
1657 continue;
1658 }
1659
1660 /* Allocate memory for the section contents. We use bfd_zalloc
1661 here in case unused entries are not reclaimed before the
1662 section's contents are written out. This should not happen,
1663 but this way if it does, we get a R_X86_64_NONE reloc instead
1664 of garbage. */
1665 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
1666 if (s->contents == NULL)
1667 return FALSE;
1668 }
1669
1670 if (htab->elf.dynamic_sections_created)
1671 {
1672 /* Add some entries to the .dynamic section. We fill in the
1673 values later, in elf64_x86_64_finish_dynamic_sections, but we
1674 must add the entries now so that we get the correct size for
1675 the .dynamic section. The DT_DEBUG entry is filled in by the
1676 dynamic linker and used by the debugger. */
1677 #define add_dynamic_entry(TAG, VAL) \
1678 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1679
1680 if (info->executable)
1681 {
1682 if (!add_dynamic_entry (DT_DEBUG, 0))
1683 return FALSE;
1684 }
1685
1686 if (htab->splt->_raw_size != 0)
1687 {
1688 if (!add_dynamic_entry (DT_PLTGOT, 0)
1689 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1690 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1691 || !add_dynamic_entry (DT_JMPREL, 0))
1692 return FALSE;
1693 }
1694
1695 if (relocs)
1696 {
1697 if (!add_dynamic_entry (DT_RELA, 0)
1698 || !add_dynamic_entry (DT_RELASZ, 0)
1699 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
1700 return FALSE;
1701
1702 /* If any dynamic relocs apply to a read-only section,
1703 then we need a DT_TEXTREL entry. */
1704 if ((info->flags & DF_TEXTREL) == 0)
1705 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
1706 (PTR) info);
1707
1708 if ((info->flags & DF_TEXTREL) != 0)
1709 {
1710 if (!add_dynamic_entry (DT_TEXTREL, 0))
1711 return FALSE;
1712 }
1713 }
1714 }
1715 #undef add_dynamic_entry
1716
1717 return TRUE;
1718 }
1719
1720 /* Return the base VMA address which should be subtracted from real addresses
1721 when resolving @dtpoff relocation.
1722 This is PT_TLS segment p_vaddr. */
1723
1724 static bfd_vma
1725 dtpoff_base (struct bfd_link_info *info)
1726 {
1727 /* If tls_sec is NULL, we should have signalled an error already. */
1728 if (elf_hash_table (info)->tls_sec == NULL)
1729 return 0;
1730 return elf_hash_table (info)->tls_sec->vma;
1731 }
1732
1733 /* Return the relocation value for @tpoff relocation
1734 if STT_TLS virtual address is ADDRESS. */
1735
1736 static bfd_vma
1737 tpoff (struct bfd_link_info *info, bfd_vma address)
1738 {
1739 struct elf_link_hash_table *htab = elf_hash_table (info);
1740
1741 /* If tls_segment is NULL, we should have signalled an error already. */
1742 if (htab->tls_sec == NULL)
1743 return 0;
1744 return address - htab->tls_size - htab->tls_sec->vma;
1745 }
1746
1747 /* Relocate an x86_64 ELF section. */
1748
1749 static bfd_boolean
1750 elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
1751 bfd *input_bfd, asection *input_section,
1752 bfd_byte *contents, Elf_Internal_Rela *relocs,
1753 Elf_Internal_Sym *local_syms,
1754 asection **local_sections)
1755 {
1756 struct elf64_x86_64_link_hash_table *htab;
1757 Elf_Internal_Shdr *symtab_hdr;
1758 struct elf_link_hash_entry **sym_hashes;
1759 bfd_vma *local_got_offsets;
1760 Elf_Internal_Rela *rel;
1761 Elf_Internal_Rela *relend;
1762
1763 if (info->relocatable)
1764 return TRUE;
1765
1766 htab = elf64_x86_64_hash_table (info);
1767 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1768 sym_hashes = elf_sym_hashes (input_bfd);
1769 local_got_offsets = elf_local_got_offsets (input_bfd);
1770
1771 rel = relocs;
1772 relend = relocs + input_section->reloc_count;
1773 for (; rel < relend; rel++)
1774 {
1775 unsigned int r_type;
1776 reloc_howto_type *howto;
1777 unsigned long r_symndx;
1778 struct elf_link_hash_entry *h;
1779 Elf_Internal_Sym *sym;
1780 asection *sec;
1781 bfd_vma off;
1782 bfd_vma relocation;
1783 bfd_boolean unresolved_reloc;
1784 bfd_reloc_status_type r;
1785 int tls_type;
1786
1787 r_type = ELF64_R_TYPE (rel->r_info);
1788 if (r_type == (int) R_X86_64_GNU_VTINHERIT
1789 || r_type == (int) R_X86_64_GNU_VTENTRY)
1790 continue;
1791
1792 if (r_type >= R_X86_64_max)
1793 {
1794 bfd_set_error (bfd_error_bad_value);
1795 return FALSE;
1796 }
1797
1798 howto = x86_64_elf_howto_table + r_type;
1799 r_symndx = ELF64_R_SYM (rel->r_info);
1800 h = NULL;
1801 sym = NULL;
1802 sec = NULL;
1803 unresolved_reloc = FALSE;
1804 if (r_symndx < symtab_hdr->sh_info)
1805 {
1806 sym = local_syms + r_symndx;
1807 sec = local_sections[r_symndx];
1808
1809 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
1810 }
1811 else
1812 {
1813 bfd_boolean warned;
1814
1815 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
1816 r_symndx, symtab_hdr, sym_hashes,
1817 h, sec, relocation,
1818 unresolved_reloc, warned);
1819 }
1820 /* When generating a shared object, the relocations handled here are
1821 copied into the output file to be resolved at run time. */
1822 switch (r_type)
1823 {
1824 case R_X86_64_GOT32:
1825 /* Relocation is to the entry for this symbol in the global
1826 offset table. */
1827 case R_X86_64_GOTPCREL:
1828 /* Use global offset table as symbol value. */
1829 if (htab->sgot == NULL)
1830 abort ();
1831
1832 if (h != NULL)
1833 {
1834 bfd_boolean dyn;
1835
1836 off = h->got.offset;
1837 dyn = htab->elf.dynamic_sections_created;
1838
1839 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
1840 || (info->shared
1841 && SYMBOL_REFERENCES_LOCAL (info, h))
1842 || (ELF_ST_VISIBILITY (h->other)
1843 && h->root.type == bfd_link_hash_undefweak))
1844 {
1845 /* This is actually a static link, or it is a -Bsymbolic
1846 link and the symbol is defined locally, or the symbol
1847 was forced to be local because of a version file. We
1848 must initialize this entry in the global offset table.
1849 Since the offset must always be a multiple of 8, we
1850 use the least significant bit to record whether we
1851 have initialized it already.
1852
1853 When doing a dynamic link, we create a .rela.got
1854 relocation entry to initialize the value. This is
1855 done in the finish_dynamic_symbol routine. */
1856 if ((off & 1) != 0)
1857 off &= ~1;
1858 else
1859 {
1860 bfd_put_64 (output_bfd, relocation,
1861 htab->sgot->contents + off);
1862 h->got.offset |= 1;
1863 }
1864 }
1865 else
1866 unresolved_reloc = FALSE;
1867 }
1868 else
1869 {
1870 if (local_got_offsets == NULL)
1871 abort ();
1872
1873 off = local_got_offsets[r_symndx];
1874
1875 /* The offset must always be a multiple of 8. We use
1876 the least significant bit to record whether we have
1877 already generated the necessary reloc. */
1878 if ((off & 1) != 0)
1879 off &= ~1;
1880 else
1881 {
1882 bfd_put_64 (output_bfd, relocation,
1883 htab->sgot->contents + off);
1884
1885 if (info->shared)
1886 {
1887 asection *s;
1888 Elf_Internal_Rela outrel;
1889 bfd_byte *loc;
1890
1891 /* We need to generate a R_X86_64_RELATIVE reloc
1892 for the dynamic linker. */
1893 s = htab->srelgot;
1894 if (s == NULL)
1895 abort ();
1896
1897 outrel.r_offset = (htab->sgot->output_section->vma
1898 + htab->sgot->output_offset
1899 + off);
1900 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
1901 outrel.r_addend = relocation;
1902 loc = s->contents;
1903 loc += s->reloc_count++ * sizeof (Elf64_External_Rela);
1904 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
1905 }
1906
1907 local_got_offsets[r_symndx] |= 1;
1908 }
1909 }
1910
1911 if (off >= (bfd_vma) -2)
1912 abort ();
1913
1914 relocation = htab->sgot->output_offset + off;
1915 if (r_type == R_X86_64_GOTPCREL)
1916 relocation += htab->sgot->output_section->vma;
1917
1918 break;
1919
1920 case R_X86_64_PLT32:
1921 /* Relocation is to the entry for this symbol in the
1922 procedure linkage table. */
1923
1924 /* Resolve a PLT32 reloc against a local symbol directly,
1925 without using the procedure linkage table. */
1926 if (h == NULL)
1927 break;
1928
1929 if (h->plt.offset == (bfd_vma) -1
1930 || htab->splt == NULL)
1931 {
1932 /* We didn't make a PLT entry for this symbol. This
1933 happens when statically linking PIC code, or when
1934 using -Bsymbolic. */
1935 break;
1936 }
1937
1938 relocation = (htab->splt->output_section->vma
1939 + htab->splt->output_offset
1940 + h->plt.offset);
1941 unresolved_reloc = FALSE;
1942 break;
1943
1944 case R_X86_64_PC8:
1945 case R_X86_64_PC16:
1946 case R_X86_64_PC32:
1947 case R_X86_64_8:
1948 case R_X86_64_16:
1949 case R_X86_64_32:
1950 case R_X86_64_64:
1951 /* FIXME: The ABI says the linker should make sure the value is
1952 the same when it's zeroextended to 64 bit. */
1953
1954 /* r_symndx will be zero only for relocs against symbols
1955 from removed linkonce sections, or sections discarded by
1956 a linker script. */
1957 if (r_symndx == 0
1958 || (input_section->flags & SEC_ALLOC) == 0)
1959 break;
1960
1961 if ((info->shared
1962 && (h == NULL
1963 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1964 || h->root.type != bfd_link_hash_undefweak)
1965 && ((r_type != R_X86_64_PC8
1966 && r_type != R_X86_64_PC16
1967 && r_type != R_X86_64_PC32)
1968 || !SYMBOL_CALLS_LOCAL (info, h)))
1969 || (ELIMINATE_COPY_RELOCS
1970 && !info->shared
1971 && h != NULL
1972 && h->dynindx != -1
1973 && (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1974 && (((h->elf_link_hash_flags
1975 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1976 && (h->elf_link_hash_flags
1977 & ELF_LINK_HASH_DEF_REGULAR) == 0)
1978 || h->root.type == bfd_link_hash_undefweak
1979 || h->root.type == bfd_link_hash_undefined)))
1980 {
1981 Elf_Internal_Rela outrel;
1982 bfd_byte *loc;
1983 bfd_boolean skip, relocate;
1984 asection *sreloc;
1985
1986 /* When generating a shared object, these relocations
1987 are copied into the output file to be resolved at run
1988 time. */
1989 skip = FALSE;
1990 relocate = FALSE;
1991
1992 outrel.r_offset =
1993 _bfd_elf_section_offset (output_bfd, info, input_section,
1994 rel->r_offset);
1995 if (outrel.r_offset == (bfd_vma) -1)
1996 skip = TRUE;
1997 else if (outrel.r_offset == (bfd_vma) -2)
1998 skip = TRUE, relocate = TRUE;
1999
2000 outrel.r_offset += (input_section->output_section->vma
2001 + input_section->output_offset);
2002
2003 if (skip)
2004 memset (&outrel, 0, sizeof outrel);
2005
2006 /* h->dynindx may be -1 if this symbol was marked to
2007 become local. */
2008 else if (h != NULL
2009 && h->dynindx != -1
2010 && (r_type == R_X86_64_PC8
2011 || r_type == R_X86_64_PC16
2012 || r_type == R_X86_64_PC32
2013 || !info->shared
2014 || !info->symbolic
2015 || (h->elf_link_hash_flags
2016 & ELF_LINK_HASH_DEF_REGULAR) == 0))
2017 {
2018 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
2019 outrel.r_addend = rel->r_addend;
2020 }
2021 else
2022 {
2023 /* This symbol is local, or marked to become local. */
2024 if (r_type == R_X86_64_64)
2025 {
2026 relocate = TRUE;
2027 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2028 outrel.r_addend = relocation + rel->r_addend;
2029 }
2030 else
2031 {
2032 long sindx;
2033
2034 if (bfd_is_abs_section (sec))
2035 sindx = 0;
2036 else if (sec == NULL || sec->owner == NULL)
2037 {
2038 bfd_set_error (bfd_error_bad_value);
2039 return FALSE;
2040 }
2041 else
2042 {
2043 asection *osec;
2044
2045 osec = sec->output_section;
2046 sindx = elf_section_data (osec)->dynindx;
2047 BFD_ASSERT (sindx > 0);
2048 }
2049
2050 outrel.r_info = ELF64_R_INFO (sindx, r_type);
2051 outrel.r_addend = relocation + rel->r_addend;
2052 }
2053 }
2054
2055 sreloc = elf_section_data (input_section)->sreloc;
2056 if (sreloc == NULL)
2057 abort ();
2058
2059 loc = sreloc->contents;
2060 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
2061 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2062
2063 /* If this reloc is against an external symbol, we do
2064 not want to fiddle with the addend. Otherwise, we
2065 need to include the symbol value so that it becomes
2066 an addend for the dynamic reloc. */
2067 if (! relocate)
2068 continue;
2069 }
2070
2071 break;
2072
2073 case R_X86_64_TLSGD:
2074 case R_X86_64_GOTTPOFF:
2075 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
2076 tls_type = GOT_UNKNOWN;
2077 if (h == NULL && local_got_offsets)
2078 tls_type = elf64_x86_64_local_got_tls_type (input_bfd) [r_symndx];
2079 else if (h != NULL)
2080 {
2081 tls_type = elf64_x86_64_hash_entry (h)->tls_type;
2082 if (!info->shared && h->dynindx == -1 && tls_type == GOT_TLS_IE)
2083 r_type = R_X86_64_TPOFF32;
2084 }
2085 if (r_type == R_X86_64_TLSGD)
2086 {
2087 if (tls_type == GOT_TLS_IE)
2088 r_type = R_X86_64_GOTTPOFF;
2089 }
2090
2091 if (r_type == R_X86_64_TPOFF32)
2092 {
2093 BFD_ASSERT (! unresolved_reloc);
2094 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
2095 {
2096 unsigned int i;
2097 static unsigned char tlsgd[8]
2098 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2099
2100 /* GD->LE transition.
2101 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2102 .word 0x6666; rex64; call __tls_get_addr@plt
2103 Change it into:
2104 movq %fs:0, %rax
2105 leaq foo@tpoff(%rax), %rax */
2106 BFD_ASSERT (rel->r_offset >= 4);
2107 for (i = 0; i < 4; i++)
2108 BFD_ASSERT (bfd_get_8 (input_bfd,
2109 contents + rel->r_offset - 4 + i)
2110 == tlsgd[i]);
2111 BFD_ASSERT (rel->r_offset + 12 <= input_section->_raw_size);
2112 for (i = 0; i < 4; i++)
2113 BFD_ASSERT (bfd_get_8 (input_bfd,
2114 contents + rel->r_offset + 4 + i)
2115 == tlsgd[i+4]);
2116 BFD_ASSERT (rel + 1 < relend);
2117 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2118 memcpy (contents + rel->r_offset - 4,
2119 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0",
2120 16);
2121 bfd_put_32 (output_bfd, tpoff (info, relocation),
2122 contents + rel->r_offset + 8);
2123 /* Skip R_X86_64_PLT32. */
2124 rel++;
2125 continue;
2126 }
2127 else
2128 {
2129 unsigned int val, type, reg;
2130
2131 /* IE->LE transition:
2132 Originally it can be one of:
2133 movq foo@gottpoff(%rip), %reg
2134 addq foo@gottpoff(%rip), %reg
2135 We change it into:
2136 movq $foo, %reg
2137 leaq foo(%reg), %reg
2138 addq $foo, %reg. */
2139 BFD_ASSERT (rel->r_offset >= 3);
2140 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 3);
2141 BFD_ASSERT (val == 0x48 || val == 0x4c);
2142 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2143 BFD_ASSERT (type == 0x8b || type == 0x03);
2144 reg = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2145 BFD_ASSERT ((reg & 0xc7) == 5);
2146 reg >>= 3;
2147 BFD_ASSERT (rel->r_offset + 4 <= input_section->_raw_size);
2148 if (type == 0x8b)
2149 {
2150 /* movq */
2151 if (val == 0x4c)
2152 bfd_put_8 (output_bfd, 0x49,
2153 contents + rel->r_offset - 3);
2154 bfd_put_8 (output_bfd, 0xc7,
2155 contents + rel->r_offset - 2);
2156 bfd_put_8 (output_bfd, 0xc0 | reg,
2157 contents + rel->r_offset - 1);
2158 }
2159 else if (reg == 4)
2160 {
2161 /* addq -> addq - addressing with %rsp/%r12 is
2162 special */
2163 if (val == 0x4c)
2164 bfd_put_8 (output_bfd, 0x49,
2165 contents + rel->r_offset - 3);
2166 bfd_put_8 (output_bfd, 0x81,
2167 contents + rel->r_offset - 2);
2168 bfd_put_8 (output_bfd, 0xc0 | reg,
2169 contents + rel->r_offset - 1);
2170 }
2171 else
2172 {
2173 /* addq -> leaq */
2174 if (val == 0x4c)
2175 bfd_put_8 (output_bfd, 0x4d,
2176 contents + rel->r_offset - 3);
2177 bfd_put_8 (output_bfd, 0x8d,
2178 contents + rel->r_offset - 2);
2179 bfd_put_8 (output_bfd, 0x80 | reg | (reg << 3),
2180 contents + rel->r_offset - 1);
2181 }
2182 bfd_put_32 (output_bfd, tpoff (info, relocation),
2183 contents + rel->r_offset);
2184 continue;
2185 }
2186 }
2187
2188 if (htab->sgot == NULL)
2189 abort ();
2190
2191 if (h != NULL)
2192 off = h->got.offset;
2193 else
2194 {
2195 if (local_got_offsets == NULL)
2196 abort ();
2197
2198 off = local_got_offsets[r_symndx];
2199 }
2200
2201 if ((off & 1) != 0)
2202 off &= ~1;
2203 else
2204 {
2205 Elf_Internal_Rela outrel;
2206 bfd_byte *loc;
2207 int dr_type, indx;
2208
2209 if (htab->srelgot == NULL)
2210 abort ();
2211
2212 outrel.r_offset = (htab->sgot->output_section->vma
2213 + htab->sgot->output_offset + off);
2214
2215 indx = h && h->dynindx != -1 ? h->dynindx : 0;
2216 if (r_type == R_X86_64_TLSGD)
2217 dr_type = R_X86_64_DTPMOD64;
2218 else
2219 dr_type = R_X86_64_TPOFF64;
2220
2221 bfd_put_64 (output_bfd, 0, htab->sgot->contents + off);
2222 outrel.r_addend = 0;
2223 if (dr_type == R_X86_64_TPOFF64 && indx == 0)
2224 outrel.r_addend = relocation - dtpoff_base (info);
2225 outrel.r_info = ELF64_R_INFO (indx, dr_type);
2226
2227 loc = htab->srelgot->contents;
2228 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2229 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2230
2231 if (r_type == R_X86_64_TLSGD)
2232 {
2233 if (indx == 0)
2234 {
2235 BFD_ASSERT (! unresolved_reloc);
2236 bfd_put_64 (output_bfd,
2237 relocation - dtpoff_base (info),
2238 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2239 }
2240 else
2241 {
2242 bfd_put_64 (output_bfd, 0,
2243 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2244 outrel.r_info = ELF64_R_INFO (indx,
2245 R_X86_64_DTPOFF64);
2246 outrel.r_offset += GOT_ENTRY_SIZE;
2247 htab->srelgot->reloc_count++;
2248 loc += sizeof (Elf64_External_Rela);
2249 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2250 }
2251 }
2252
2253 if (h != NULL)
2254 h->got.offset |= 1;
2255 else
2256 local_got_offsets[r_symndx] |= 1;
2257 }
2258
2259 if (off >= (bfd_vma) -2)
2260 abort ();
2261 if (r_type == ELF64_R_TYPE (rel->r_info))
2262 {
2263 relocation = htab->sgot->output_section->vma
2264 + htab->sgot->output_offset + off;
2265 unresolved_reloc = FALSE;
2266 }
2267 else
2268 {
2269 unsigned int i;
2270 static unsigned char tlsgd[8]
2271 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2272
2273 /* GD->IE transition.
2274 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2275 .word 0x6666; rex64; call __tls_get_addr@plt
2276 Change it into:
2277 movq %fs:0, %rax
2278 addq foo@gottpoff(%rip), %rax */
2279 BFD_ASSERT (rel->r_offset >= 4);
2280 for (i = 0; i < 4; i++)
2281 BFD_ASSERT (bfd_get_8 (input_bfd,
2282 contents + rel->r_offset - 4 + i)
2283 == tlsgd[i]);
2284 BFD_ASSERT (rel->r_offset + 12 <= input_section->_raw_size);
2285 for (i = 0; i < 4; i++)
2286 BFD_ASSERT (bfd_get_8 (input_bfd,
2287 contents + rel->r_offset + 4 + i)
2288 == tlsgd[i+4]);
2289 BFD_ASSERT (rel + 1 < relend);
2290 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2291 memcpy (contents + rel->r_offset - 4,
2292 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0",
2293 16);
2294
2295 relocation = (htab->sgot->output_section->vma
2296 + htab->sgot->output_offset + off
2297 - rel->r_offset
2298 - input_section->output_section->vma
2299 - input_section->output_offset
2300 - 12);
2301 bfd_put_32 (output_bfd, relocation,
2302 contents + rel->r_offset + 8);
2303 /* Skip R_X86_64_PLT32. */
2304 rel++;
2305 continue;
2306 }
2307 break;
2308
2309 case R_X86_64_TLSLD:
2310 if (! info->shared)
2311 {
2312 /* LD->LE transition:
2313 Ensure it is:
2314 leaq foo@tlsld(%rip), %rdi; call __tls_get_addr@plt.
2315 We change it into:
2316 .word 0x6666; .byte 0x66; movl %fs:0, %rax. */
2317 BFD_ASSERT (rel->r_offset >= 3);
2318 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 3)
2319 == 0x48);
2320 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 2)
2321 == 0x8d);
2322 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 1)
2323 == 0x3d);
2324 BFD_ASSERT (rel->r_offset + 9 <= input_section->_raw_size);
2325 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2326 == 0xe8);
2327 BFD_ASSERT (rel + 1 < relend);
2328 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2329 memcpy (contents + rel->r_offset - 3,
2330 "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0", 12);
2331 /* Skip R_X86_64_PLT32. */
2332 rel++;
2333 continue;
2334 }
2335
2336 if (htab->sgot == NULL)
2337 abort ();
2338
2339 off = htab->tls_ld_got.offset;
2340 if (off & 1)
2341 off &= ~1;
2342 else
2343 {
2344 Elf_Internal_Rela outrel;
2345 bfd_byte *loc;
2346
2347 if (htab->srelgot == NULL)
2348 abort ();
2349
2350 outrel.r_offset = (htab->sgot->output_section->vma
2351 + htab->sgot->output_offset + off);
2352
2353 bfd_put_64 (output_bfd, 0,
2354 htab->sgot->contents + off);
2355 bfd_put_64 (output_bfd, 0,
2356 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2357 outrel.r_info = ELF64_R_INFO (0, R_X86_64_DTPMOD64);
2358 outrel.r_addend = 0;
2359 loc = htab->srelgot->contents;
2360 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2361 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2362 htab->tls_ld_got.offset |= 1;
2363 }
2364 relocation = htab->sgot->output_section->vma
2365 + htab->sgot->output_offset + off;
2366 unresolved_reloc = FALSE;
2367 break;
2368
2369 case R_X86_64_DTPOFF32:
2370 if (info->shared || (input_section->flags & SEC_CODE) == 0)
2371 relocation -= dtpoff_base (info);
2372 else
2373 relocation = tpoff (info, relocation);
2374 break;
2375
2376 case R_X86_64_TPOFF32:
2377 BFD_ASSERT (! info->shared);
2378 relocation = tpoff (info, relocation);
2379 break;
2380
2381 default:
2382 break;
2383 }
2384
2385 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
2386 because such sections are not SEC_ALLOC and thus ld.so will
2387 not process them. */
2388 if (unresolved_reloc
2389 && !((input_section->flags & SEC_DEBUGGING) != 0
2390 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
2391 (*_bfd_error_handler)
2392 (_("%s(%s+0x%lx): unresolvable relocation against symbol `%s'"),
2393 bfd_archive_filename (input_bfd),
2394 bfd_get_section_name (input_bfd, input_section),
2395 (long) rel->r_offset,
2396 h->root.root.string);
2397
2398 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
2399 contents, rel->r_offset,
2400 relocation, rel->r_addend);
2401
2402 if (r != bfd_reloc_ok)
2403 {
2404 const char *name;
2405
2406 if (h != NULL)
2407 name = h->root.root.string;
2408 else
2409 {
2410 name = bfd_elf_string_from_elf_section (input_bfd,
2411 symtab_hdr->sh_link,
2412 sym->st_name);
2413 if (name == NULL)
2414 return FALSE;
2415 if (*name == '\0')
2416 name = bfd_section_name (input_bfd, sec);
2417 }
2418
2419 if (r == bfd_reloc_overflow)
2420 {
2421
2422 if (! ((*info->callbacks->reloc_overflow)
2423 (info, name, howto->name, (bfd_vma) 0,
2424 input_bfd, input_section, rel->r_offset)))
2425 return FALSE;
2426 }
2427 else
2428 {
2429 (*_bfd_error_handler)
2430 (_("%s(%s+0x%lx): reloc against `%s': error %d"),
2431 bfd_archive_filename (input_bfd),
2432 bfd_get_section_name (input_bfd, input_section),
2433 (long) rel->r_offset, name, (int) r);
2434 return FALSE;
2435 }
2436 }
2437 }
2438
2439 return TRUE;
2440 }
2441
2442 /* Finish up dynamic symbol handling. We set the contents of various
2443 dynamic sections here. */
2444
2445 static bfd_boolean
2446 elf64_x86_64_finish_dynamic_symbol (bfd *output_bfd,
2447 struct bfd_link_info *info,
2448 struct elf_link_hash_entry *h,
2449 Elf_Internal_Sym *sym)
2450 {
2451 struct elf64_x86_64_link_hash_table *htab;
2452
2453 htab = elf64_x86_64_hash_table (info);
2454
2455 if (h->plt.offset != (bfd_vma) -1)
2456 {
2457 bfd_vma plt_index;
2458 bfd_vma got_offset;
2459 Elf_Internal_Rela rela;
2460 bfd_byte *loc;
2461
2462 /* This symbol has an entry in the procedure linkage table. Set
2463 it up. */
2464 if (h->dynindx == -1
2465 || htab->splt == NULL
2466 || htab->sgotplt == NULL
2467 || htab->srelplt == NULL)
2468 abort ();
2469
2470 /* Get the index in the procedure linkage table which
2471 corresponds to this symbol. This is the index of this symbol
2472 in all the symbols for which we are making plt entries. The
2473 first entry in the procedure linkage table is reserved. */
2474 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2475
2476 /* Get the offset into the .got table of the entry that
2477 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
2478 bytes. The first three are reserved for the dynamic linker. */
2479 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
2480
2481 /* Fill in the entry in the procedure linkage table. */
2482 memcpy (htab->splt->contents + h->plt.offset, elf64_x86_64_plt_entry,
2483 PLT_ENTRY_SIZE);
2484
2485 /* Insert the relocation positions of the plt section. The magic
2486 numbers at the end of the statements are the positions of the
2487 relocations in the plt section. */
2488 /* Put offset for jmp *name@GOTPCREL(%rip), since the
2489 instruction uses 6 bytes, subtract this value. */
2490 bfd_put_32 (output_bfd,
2491 (htab->sgotplt->output_section->vma
2492 + htab->sgotplt->output_offset
2493 + got_offset
2494 - htab->splt->output_section->vma
2495 - htab->splt->output_offset
2496 - h->plt.offset
2497 - 6),
2498 htab->splt->contents + h->plt.offset + 2);
2499 /* Put relocation index. */
2500 bfd_put_32 (output_bfd, plt_index,
2501 htab->splt->contents + h->plt.offset + 7);
2502 /* Put offset for jmp .PLT0. */
2503 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
2504 htab->splt->contents + h->plt.offset + 12);
2505
2506 /* Fill in the entry in the global offset table, initially this
2507 points to the pushq instruction in the PLT which is at offset 6. */
2508 bfd_put_64 (output_bfd, (htab->splt->output_section->vma
2509 + htab->splt->output_offset
2510 + h->plt.offset + 6),
2511 htab->sgotplt->contents + got_offset);
2512
2513 /* Fill in the entry in the .rela.plt section. */
2514 rela.r_offset = (htab->sgotplt->output_section->vma
2515 + htab->sgotplt->output_offset
2516 + got_offset);
2517 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
2518 rela.r_addend = 0;
2519 loc = htab->srelplt->contents + plt_index * sizeof (Elf64_External_Rela);
2520 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2521
2522 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2523 {
2524 /* Mark the symbol as undefined, rather than as defined in
2525 the .plt section. Leave the value if there were any
2526 relocations where pointer equality matters (this is a clue
2527 for the dynamic linker, to make function pointer
2528 comparisons work between an application and shared
2529 library), otherwise set it to zero. If a function is only
2530 called from a binary, there is no need to slow down
2531 shared libraries because of that. */
2532 sym->st_shndx = SHN_UNDEF;
2533 if ((h->elf_link_hash_flags & ELF_LINK_POINTER_EQUALITY_NEEDED) == 0)
2534 sym->st_value = 0;
2535 }
2536 }
2537
2538 if (h->got.offset != (bfd_vma) -1
2539 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_GD
2540 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE)
2541 {
2542 Elf_Internal_Rela rela;
2543 bfd_byte *loc;
2544
2545 /* This symbol has an entry in the global offset table. Set it
2546 up. */
2547 if (htab->sgot == NULL || htab->srelgot == NULL)
2548 abort ();
2549
2550 rela.r_offset = (htab->sgot->output_section->vma
2551 + htab->sgot->output_offset
2552 + (h->got.offset &~ (bfd_vma) 1));
2553
2554 /* If this is a static link, or it is a -Bsymbolic link and the
2555 symbol is defined locally or was forced to be local because
2556 of a version file, we just want to emit a RELATIVE reloc.
2557 The entry in the global offset table will already have been
2558 initialized in the relocate_section function. */
2559 if (info->shared
2560 && SYMBOL_REFERENCES_LOCAL (info, h))
2561 {
2562 BFD_ASSERT((h->got.offset & 1) != 0);
2563 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2564 rela.r_addend = (h->root.u.def.value
2565 + h->root.u.def.section->output_section->vma
2566 + h->root.u.def.section->output_offset);
2567 }
2568 else
2569 {
2570 BFD_ASSERT((h->got.offset & 1) == 0);
2571 bfd_put_64 (output_bfd, (bfd_vma) 0,
2572 htab->sgot->contents + h->got.offset);
2573 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
2574 rela.r_addend = 0;
2575 }
2576
2577 loc = htab->srelgot->contents;
2578 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2579 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2580 }
2581
2582 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
2583 {
2584 Elf_Internal_Rela rela;
2585 bfd_byte *loc;
2586
2587 /* This symbol needs a copy reloc. Set it up. */
2588
2589 if (h->dynindx == -1
2590 || (h->root.type != bfd_link_hash_defined
2591 && h->root.type != bfd_link_hash_defweak)
2592 || htab->srelbss == NULL)
2593 abort ();
2594
2595 rela.r_offset = (h->root.u.def.value
2596 + h->root.u.def.section->output_section->vma
2597 + h->root.u.def.section->output_offset);
2598 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
2599 rela.r_addend = 0;
2600 loc = htab->srelbss->contents;
2601 loc += htab->srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
2602 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2603 }
2604
2605 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
2606 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
2607 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
2608 sym->st_shndx = SHN_ABS;
2609
2610 return TRUE;
2611 }
2612
2613 /* Used to decide how to sort relocs in an optimal manner for the
2614 dynamic linker, before writing them out. */
2615
2616 static enum elf_reloc_type_class
2617 elf64_x86_64_reloc_type_class (const Elf_Internal_Rela *rela)
2618 {
2619 switch ((int) ELF64_R_TYPE (rela->r_info))
2620 {
2621 case R_X86_64_RELATIVE:
2622 return reloc_class_relative;
2623 case R_X86_64_JUMP_SLOT:
2624 return reloc_class_plt;
2625 case R_X86_64_COPY:
2626 return reloc_class_copy;
2627 default:
2628 return reloc_class_normal;
2629 }
2630 }
2631
2632 /* Finish up the dynamic sections. */
2633
2634 static bfd_boolean
2635 elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
2636 {
2637 struct elf64_x86_64_link_hash_table *htab;
2638 bfd *dynobj;
2639 asection *sdyn;
2640
2641 htab = elf64_x86_64_hash_table (info);
2642 dynobj = htab->elf.dynobj;
2643 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2644
2645 if (htab->elf.dynamic_sections_created)
2646 {
2647 Elf64_External_Dyn *dyncon, *dynconend;
2648
2649 if (sdyn == NULL || htab->sgot == NULL)
2650 abort ();
2651
2652 dyncon = (Elf64_External_Dyn *) sdyn->contents;
2653 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
2654 for (; dyncon < dynconend; dyncon++)
2655 {
2656 Elf_Internal_Dyn dyn;
2657 asection *s;
2658
2659 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
2660
2661 switch (dyn.d_tag)
2662 {
2663 default:
2664 continue;
2665
2666 case DT_PLTGOT:
2667 dyn.d_un.d_ptr = htab->sgot->output_section->vma;
2668 break;
2669
2670 case DT_JMPREL:
2671 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
2672 break;
2673
2674 case DT_PLTRELSZ:
2675 s = htab->srelplt->output_section;
2676 if (s->_cooked_size != 0)
2677 dyn.d_un.d_val = s->_cooked_size;
2678 else
2679 dyn.d_un.d_val = s->_raw_size;
2680 break;
2681
2682 case DT_RELASZ:
2683 /* The procedure linkage table relocs (DT_JMPREL) should
2684 not be included in the overall relocs (DT_RELA).
2685 Therefore, we override the DT_RELASZ entry here to
2686 make it not include the JMPREL relocs. Since the
2687 linker script arranges for .rela.plt to follow all
2688 other relocation sections, we don't have to worry
2689 about changing the DT_RELA entry. */
2690 if (htab->srelplt != NULL)
2691 {
2692 s = htab->srelplt->output_section;
2693 if (s->_cooked_size != 0)
2694 dyn.d_un.d_val -= s->_cooked_size;
2695 else
2696 dyn.d_un.d_val -= s->_raw_size;
2697 }
2698 break;
2699 }
2700
2701 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
2702 }
2703
2704 /* Fill in the special first entry in the procedure linkage table. */
2705 if (htab->splt && htab->splt->_raw_size > 0)
2706 {
2707 /* Fill in the first entry in the procedure linkage table. */
2708 memcpy (htab->splt->contents, elf64_x86_64_plt0_entry,
2709 PLT_ENTRY_SIZE);
2710 /* Add offset for pushq GOT+8(%rip), since the instruction
2711 uses 6 bytes subtract this value. */
2712 bfd_put_32 (output_bfd,
2713 (htab->sgotplt->output_section->vma
2714 + htab->sgotplt->output_offset
2715 + 8
2716 - htab->splt->output_section->vma
2717 - htab->splt->output_offset
2718 - 6),
2719 htab->splt->contents + 2);
2720 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
2721 the end of the instruction. */
2722 bfd_put_32 (output_bfd,
2723 (htab->sgotplt->output_section->vma
2724 + htab->sgotplt->output_offset
2725 + 16
2726 - htab->splt->output_section->vma
2727 - htab->splt->output_offset
2728 - 12),
2729 htab->splt->contents + 8);
2730
2731 elf_section_data (htab->splt->output_section)->this_hdr.sh_entsize =
2732 PLT_ENTRY_SIZE;
2733 }
2734 }
2735
2736 if (htab->sgotplt)
2737 {
2738 /* Fill in the first three entries in the global offset table. */
2739 if (htab->sgotplt->_raw_size > 0)
2740 {
2741 /* Set the first entry in the global offset table to the address of
2742 the dynamic section. */
2743 if (sdyn == NULL)
2744 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents);
2745 else
2746 bfd_put_64 (output_bfd,
2747 sdyn->output_section->vma + sdyn->output_offset,
2748 htab->sgotplt->contents);
2749 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
2750 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE);
2751 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE*2);
2752 }
2753
2754 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize =
2755 GOT_ENTRY_SIZE;
2756 }
2757
2758 return TRUE;
2759 }
2760
2761 /* Return address for Ith PLT stub in section PLT, for relocation REL
2762 or (bfd_vma) -1 if it should not be included. */
2763
2764 static bfd_vma
2765 elf64_x86_64_plt_sym_val (bfd_vma i, const asection *plt,
2766 const arelent *rel ATTRIBUTE_UNUSED)
2767 {
2768 return plt->vma + (i + 1) * PLT_ENTRY_SIZE;
2769 }
2770
2771 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
2772 #define TARGET_LITTLE_NAME "elf64-x86-64"
2773 #define ELF_ARCH bfd_arch_i386
2774 #define ELF_MACHINE_CODE EM_X86_64
2775 #define ELF_MAXPAGESIZE 0x100000
2776
2777 #define elf_backend_can_gc_sections 1
2778 #define elf_backend_can_refcount 1
2779 #define elf_backend_want_got_plt 1
2780 #define elf_backend_plt_readonly 1
2781 #define elf_backend_want_plt_sym 0
2782 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
2783 #define elf_backend_rela_normal 1
2784
2785 #define elf_info_to_howto elf64_x86_64_info_to_howto
2786
2787 #define bfd_elf64_bfd_link_hash_table_create \
2788 elf64_x86_64_link_hash_table_create
2789 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
2790
2791 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
2792 #define elf_backend_check_relocs elf64_x86_64_check_relocs
2793 #define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol
2794 #define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections
2795 #define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections
2796 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
2797 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
2798 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
2799 #define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus
2800 #define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo
2801 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
2802 #define elf_backend_relocate_section elf64_x86_64_relocate_section
2803 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
2804 #define elf_backend_plt_sym_val elf64_x86_64_plt_sym_val
2805 #define elf_backend_object_p elf64_x86_64_elf_object_p
2806 #define bfd_elf64_mkobject elf64_x86_64_mkobject
2807
2808 #include "elf64-target.h"
This page took 0.168922 seconds and 4 git commands to generate.