2004-06-24 H.J. Lu <hongjiu.lu@intel.com>
[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 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 size = 216;
217
218 break;
219 }
220
221 /* Make a ".reg/999" section. */
222 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
223 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 against `%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 (h) ? h->root.root.string : "a local symbol");
670 bfd_set_error (bfd_error_bad_value);
671 return FALSE;
672 }
673 break;
674
675 case R_X86_64_GOTTPOFF:
676 if (info->shared)
677 info->flags |= DF_STATIC_TLS;
678 /* Fall through */
679
680 case R_X86_64_GOT32:
681 case R_X86_64_GOTPCREL:
682 case R_X86_64_TLSGD:
683 /* This symbol requires a global offset table entry. */
684 {
685 int tls_type, old_tls_type;
686
687 switch (r_type)
688 {
689 default: tls_type = GOT_NORMAL; break;
690 case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
691 case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
692 }
693
694 if (h != NULL)
695 {
696 h->got.refcount += 1;
697 old_tls_type = elf64_x86_64_hash_entry (h)->tls_type;
698 }
699 else
700 {
701 bfd_signed_vma *local_got_refcounts;
702
703 /* This is a global offset table entry for a local symbol. */
704 local_got_refcounts = elf_local_got_refcounts (abfd);
705 if (local_got_refcounts == NULL)
706 {
707 bfd_size_type size;
708
709 size = symtab_hdr->sh_info;
710 size *= sizeof (bfd_signed_vma) + sizeof (char);
711 local_got_refcounts = ((bfd_signed_vma *)
712 bfd_zalloc (abfd, size));
713 if (local_got_refcounts == NULL)
714 return FALSE;
715 elf_local_got_refcounts (abfd) = local_got_refcounts;
716 elf64_x86_64_local_got_tls_type (abfd)
717 = (char *) (local_got_refcounts + symtab_hdr->sh_info);
718 }
719 local_got_refcounts[r_symndx] += 1;
720 old_tls_type
721 = elf64_x86_64_local_got_tls_type (abfd) [r_symndx];
722 }
723
724 /* If a TLS symbol is accessed using IE at least once,
725 there is no point to use dynamic model for it. */
726 if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
727 && (old_tls_type != GOT_TLS_GD || tls_type != GOT_TLS_IE))
728 {
729 if (old_tls_type == GOT_TLS_IE && tls_type == GOT_TLS_GD)
730 tls_type = old_tls_type;
731 else
732 {
733 (*_bfd_error_handler)
734 (_("%s: %s' accessed both as normal and thread local symbol"),
735 bfd_archive_filename (abfd),
736 h ? h->root.root.string : "<local>");
737 return FALSE;
738 }
739 }
740
741 if (old_tls_type != tls_type)
742 {
743 if (h != NULL)
744 elf64_x86_64_hash_entry (h)->tls_type = tls_type;
745 else
746 elf64_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
747 }
748 }
749 /* Fall through */
750
751 //case R_X86_64_GOTPCREL:
752 create_got:
753 if (htab->sgot == NULL)
754 {
755 if (htab->elf.dynobj == NULL)
756 htab->elf.dynobj = abfd;
757 if (!create_got_section (htab->elf.dynobj, info))
758 return FALSE;
759 }
760 break;
761
762 case R_X86_64_PLT32:
763 /* This symbol requires a procedure linkage table entry. We
764 actually build the entry in adjust_dynamic_symbol,
765 because this might be a case of linking PIC code which is
766 never referenced by a dynamic object, in which case we
767 don't need to generate a procedure linkage table entry
768 after all. */
769
770 /* If this is a local symbol, we resolve it directly without
771 creating a procedure linkage table entry. */
772 if (h == NULL)
773 continue;
774
775 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
776 h->plt.refcount += 1;
777 break;
778
779 case R_X86_64_8:
780 case R_X86_64_16:
781 case R_X86_64_32:
782 case R_X86_64_32S:
783 /* Let's help debug shared library creation. These relocs
784 cannot be used in shared libs. Don't error out for
785 sections we don't care about, such as debug sections or
786 non-constant sections. */
787 if (info->shared
788 && (sec->flags & SEC_ALLOC) != 0
789 && (sec->flags & SEC_READONLY) != 0)
790 {
791 (*_bfd_error_handler)
792 (_("%s: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
793 bfd_archive_filename (abfd),
794 x86_64_elf_howto_table[r_type].name,
795 (h) ? h->root.root.string : "a local symbol");
796 bfd_set_error (bfd_error_bad_value);
797 return FALSE;
798 }
799 /* Fall through. */
800
801 case R_X86_64_PC8:
802 case R_X86_64_PC16:
803 case R_X86_64_PC32:
804 case R_X86_64_64:
805 if (h != NULL && !info->shared)
806 {
807 /* If this reloc is in a read-only section, we might
808 need a copy reloc. We can't check reliably at this
809 stage whether the section is read-only, as input
810 sections have not yet been mapped to output sections.
811 Tentatively set the flag for now, and correct in
812 adjust_dynamic_symbol. */
813 h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF;
814
815 /* We may need a .plt entry if the function this reloc
816 refers to is in a shared lib. */
817 h->plt.refcount += 1;
818 if (r_type != R_X86_64_PC32)
819 h->elf_link_hash_flags |= ELF_LINK_POINTER_EQUALITY_NEEDED;
820 }
821
822 /* If we are creating a shared library, and this is a reloc
823 against a global symbol, or a non PC relative reloc
824 against a local symbol, then we need to copy the reloc
825 into the shared library. However, if we are linking with
826 -Bsymbolic, we do not need to copy a reloc against a
827 global symbol which is defined in an object we are
828 including in the link (i.e., DEF_REGULAR is set). At
829 this point we have not seen all the input files, so it is
830 possible that DEF_REGULAR is not set now but will be set
831 later (it is never cleared). In case of a weak definition,
832 DEF_REGULAR may be cleared later by a strong definition in
833 a shared library. We account for that possibility below by
834 storing information in the relocs_copied field of the hash
835 table entry. A similar situation occurs when creating
836 shared libraries and symbol visibility changes render the
837 symbol local.
838
839 If on the other hand, we are creating an executable, we
840 may need to keep relocations for symbols satisfied by a
841 dynamic library if we manage to avoid copy relocs for the
842 symbol. */
843 if ((info->shared
844 && (sec->flags & SEC_ALLOC) != 0
845 && (((r_type != R_X86_64_PC8)
846 && (r_type != R_X86_64_PC16)
847 && (r_type != R_X86_64_PC32))
848 || (h != NULL
849 && (! info->symbolic
850 || h->root.type == bfd_link_hash_defweak
851 || (h->elf_link_hash_flags
852 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
853 || (ELIMINATE_COPY_RELOCS
854 && !info->shared
855 && (sec->flags & SEC_ALLOC) != 0
856 && h != NULL
857 && (h->root.type == bfd_link_hash_defweak
858 || (h->elf_link_hash_flags
859 & ELF_LINK_HASH_DEF_REGULAR) == 0)))
860 {
861 struct elf64_x86_64_dyn_relocs *p;
862 struct elf64_x86_64_dyn_relocs **head;
863
864 /* We must copy these reloc types into the output file.
865 Create a reloc section in dynobj and make room for
866 this reloc. */
867 if (sreloc == NULL)
868 {
869 const char *name;
870 bfd *dynobj;
871
872 name = (bfd_elf_string_from_elf_section
873 (abfd,
874 elf_elfheader (abfd)->e_shstrndx,
875 elf_section_data (sec)->rel_hdr.sh_name));
876 if (name == NULL)
877 return FALSE;
878
879 if (strncmp (name, ".rela", 5) != 0
880 || strcmp (bfd_get_section_name (abfd, sec),
881 name + 5) != 0)
882 {
883 (*_bfd_error_handler)
884 (_("%s: bad relocation section name `%s\'"),
885 bfd_archive_filename (abfd), name);
886 }
887
888 if (htab->elf.dynobj == NULL)
889 htab->elf.dynobj = abfd;
890
891 dynobj = htab->elf.dynobj;
892
893 sreloc = bfd_get_section_by_name (dynobj, name);
894 if (sreloc == NULL)
895 {
896 flagword flags;
897
898 sreloc = bfd_make_section (dynobj, name);
899 flags = (SEC_HAS_CONTENTS | SEC_READONLY
900 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
901 if ((sec->flags & SEC_ALLOC) != 0)
902 flags |= SEC_ALLOC | SEC_LOAD;
903 if (sreloc == NULL
904 || ! bfd_set_section_flags (dynobj, sreloc, flags)
905 || ! bfd_set_section_alignment (dynobj, sreloc, 3))
906 return FALSE;
907 }
908 elf_section_data (sec)->sreloc = sreloc;
909 }
910
911 /* If this is a global symbol, we count the number of
912 relocations we need for this symbol. */
913 if (h != NULL)
914 {
915 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs;
916 }
917 else
918 {
919 /* Track dynamic relocs needed for local syms too.
920 We really need local syms available to do this
921 easily. Oh well. */
922
923 asection *s;
924 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
925 sec, r_symndx);
926 if (s == NULL)
927 return FALSE;
928
929 head = ((struct elf64_x86_64_dyn_relocs **)
930 &elf_section_data (s)->local_dynrel);
931 }
932
933 p = *head;
934 if (p == NULL || p->sec != sec)
935 {
936 bfd_size_type amt = sizeof *p;
937 p = ((struct elf64_x86_64_dyn_relocs *)
938 bfd_alloc (htab->elf.dynobj, amt));
939 if (p == NULL)
940 return FALSE;
941 p->next = *head;
942 *head = p;
943 p->sec = sec;
944 p->count = 0;
945 p->pc_count = 0;
946 }
947
948 p->count += 1;
949 if (r_type == R_X86_64_PC8
950 || r_type == R_X86_64_PC16
951 || r_type == R_X86_64_PC32)
952 p->pc_count += 1;
953 }
954 break;
955
956 /* This relocation describes the C++ object vtable hierarchy.
957 Reconstruct it for later use during GC. */
958 case R_X86_64_GNU_VTINHERIT:
959 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
960 return FALSE;
961 break;
962
963 /* This relocation describes which C++ vtable entries are actually
964 used. Record for later use during GC. */
965 case R_X86_64_GNU_VTENTRY:
966 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
967 return FALSE;
968 break;
969
970 default:
971 break;
972 }
973 }
974
975 return TRUE;
976 }
977
978 /* Return the section that should be marked against GC for a given
979 relocation. */
980
981 static asection *
982 elf64_x86_64_gc_mark_hook (asection *sec,
983 struct bfd_link_info *info ATTRIBUTE_UNUSED,
984 Elf_Internal_Rela *rel,
985 struct elf_link_hash_entry *h,
986 Elf_Internal_Sym *sym)
987 {
988 if (h != NULL)
989 {
990 switch (ELF64_R_TYPE (rel->r_info))
991 {
992 case R_X86_64_GNU_VTINHERIT:
993 case R_X86_64_GNU_VTENTRY:
994 break;
995
996 default:
997 switch (h->root.type)
998 {
999 case bfd_link_hash_defined:
1000 case bfd_link_hash_defweak:
1001 return h->root.u.def.section;
1002
1003 case bfd_link_hash_common:
1004 return h->root.u.c.p->section;
1005
1006 default:
1007 break;
1008 }
1009 }
1010 }
1011 else
1012 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
1013
1014 return NULL;
1015 }
1016
1017 /* Update the got entry reference counts for the section being removed. */
1018
1019 static bfd_boolean
1020 elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
1021 asection *sec, const Elf_Internal_Rela *relocs)
1022 {
1023 Elf_Internal_Shdr *symtab_hdr;
1024 struct elf_link_hash_entry **sym_hashes;
1025 bfd_signed_vma *local_got_refcounts;
1026 const Elf_Internal_Rela *rel, *relend;
1027
1028 elf_section_data (sec)->local_dynrel = NULL;
1029
1030 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1031 sym_hashes = elf_sym_hashes (abfd);
1032 local_got_refcounts = elf_local_got_refcounts (abfd);
1033
1034 relend = relocs + sec->reloc_count;
1035 for (rel = relocs; rel < relend; rel++)
1036 {
1037 unsigned long r_symndx;
1038 unsigned int r_type;
1039 struct elf_link_hash_entry *h = NULL;
1040
1041 r_symndx = ELF64_R_SYM (rel->r_info);
1042 if (r_symndx >= symtab_hdr->sh_info)
1043 {
1044 struct elf64_x86_64_link_hash_entry *eh;
1045 struct elf64_x86_64_dyn_relocs **pp;
1046 struct elf64_x86_64_dyn_relocs *p;
1047
1048 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1049 eh = (struct elf64_x86_64_link_hash_entry *) h;
1050
1051 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1052 if (p->sec == sec)
1053 {
1054 /* Everything must go for SEC. */
1055 *pp = p->next;
1056 break;
1057 }
1058 }
1059
1060 r_type = ELF64_R_TYPE (rel->r_info);
1061 r_type = elf64_x86_64_tls_transition (info, r_type, h != NULL);
1062 switch (r_type)
1063 {
1064 case R_X86_64_TLSLD:
1065 if (elf64_x86_64_hash_table (info)->tls_ld_got.refcount > 0)
1066 elf64_x86_64_hash_table (info)->tls_ld_got.refcount -= 1;
1067 break;
1068
1069 case R_X86_64_TLSGD:
1070 case R_X86_64_GOTTPOFF:
1071 case R_X86_64_GOT32:
1072 case R_X86_64_GOTPCREL:
1073 if (h != NULL)
1074 {
1075 if (h->got.refcount > 0)
1076 h->got.refcount -= 1;
1077 }
1078 else if (local_got_refcounts != NULL)
1079 {
1080 if (local_got_refcounts[r_symndx] > 0)
1081 local_got_refcounts[r_symndx] -= 1;
1082 }
1083 break;
1084
1085 case R_X86_64_8:
1086 case R_X86_64_16:
1087 case R_X86_64_32:
1088 case R_X86_64_64:
1089 case R_X86_64_32S:
1090 case R_X86_64_PC8:
1091 case R_X86_64_PC16:
1092 case R_X86_64_PC32:
1093 if (info->shared)
1094 break;
1095 /* Fall thru */
1096
1097 case R_X86_64_PLT32:
1098 if (h != NULL)
1099 {
1100 if (h->plt.refcount > 0)
1101 h->plt.refcount -= 1;
1102 }
1103 break;
1104
1105 default:
1106 break;
1107 }
1108 }
1109
1110 return TRUE;
1111 }
1112
1113 /* Adjust a symbol defined by a dynamic object and referenced by a
1114 regular object. The current definition is in some section of the
1115 dynamic object, but we're not including those sections. We have to
1116 change the definition to something the rest of the link can
1117 understand. */
1118
1119 static bfd_boolean
1120 elf64_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
1121 struct elf_link_hash_entry *h)
1122 {
1123 struct elf64_x86_64_link_hash_table *htab;
1124 asection *s;
1125 unsigned int power_of_two;
1126
1127 /* If this is a function, put it in the procedure linkage table. We
1128 will fill in the contents of the procedure linkage table later,
1129 when we know the address of the .got section. */
1130 if (h->type == STT_FUNC
1131 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
1132 {
1133 if (h->plt.refcount <= 0
1134 || SYMBOL_CALLS_LOCAL (info, h)
1135 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1136 && h->root.type == bfd_link_hash_undefweak))
1137 {
1138 /* This case can occur if we saw a PLT32 reloc in an input
1139 file, but the symbol was never referred to by a dynamic
1140 object, or if all references were garbage collected. In
1141 such a case, we don't actually need to build a procedure
1142 linkage table, and we can just do a PC32 reloc instead. */
1143 h->plt.offset = (bfd_vma) -1;
1144 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1145 }
1146
1147 return TRUE;
1148 }
1149 else
1150 /* It's possible that we incorrectly decided a .plt reloc was
1151 needed for an R_X86_64_PC32 reloc to a non-function sym in
1152 check_relocs. We can't decide accurately between function and
1153 non-function syms in check-relocs; Objects loaded later in
1154 the link may change h->type. So fix it now. */
1155 h->plt.offset = (bfd_vma) -1;
1156
1157 /* If this is a weak symbol, and there is a real definition, the
1158 processor independent code will have arranged for us to see the
1159 real definition first, and we can just use the same value. */
1160 if (h->weakdef != NULL)
1161 {
1162 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
1163 || h->weakdef->root.type == bfd_link_hash_defweak);
1164 h->root.u.def.section = h->weakdef->root.u.def.section;
1165 h->root.u.def.value = h->weakdef->root.u.def.value;
1166 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1167 h->elf_link_hash_flags
1168 = ((h->elf_link_hash_flags & ~ELF_LINK_NON_GOT_REF)
1169 | (h->weakdef->elf_link_hash_flags & ELF_LINK_NON_GOT_REF));
1170 return TRUE;
1171 }
1172
1173 /* This is a reference to a symbol defined by a dynamic object which
1174 is not a function. */
1175
1176 /* If we are creating a shared library, we must presume that the
1177 only references to the symbol are via the global offset table.
1178 For such cases we need not do anything here; the relocations will
1179 be handled correctly by relocate_section. */
1180 if (info->shared)
1181 return TRUE;
1182
1183 /* If there are no references to this symbol that do not use the
1184 GOT, we don't need to generate a copy reloc. */
1185 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0)
1186 return TRUE;
1187
1188 /* If -z nocopyreloc was given, we won't generate them either. */
1189 if (info->nocopyreloc)
1190 {
1191 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1192 return TRUE;
1193 }
1194
1195 if (ELIMINATE_COPY_RELOCS)
1196 {
1197 struct elf64_x86_64_link_hash_entry * eh;
1198 struct elf64_x86_64_dyn_relocs *p;
1199
1200 eh = (struct elf64_x86_64_link_hash_entry *) h;
1201 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1202 {
1203 s = p->sec->output_section;
1204 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1205 break;
1206 }
1207
1208 /* If we didn't find any dynamic relocs in read-only sections, then
1209 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1210 if (p == NULL)
1211 {
1212 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1213 return TRUE;
1214 }
1215 }
1216
1217 /* We must allocate the symbol in our .dynbss section, which will
1218 become part of the .bss section of the executable. There will be
1219 an entry for this symbol in the .dynsym section. The dynamic
1220 object will contain position independent code, so all references
1221 from the dynamic object to this symbol will go through the global
1222 offset table. The dynamic linker will use the .dynsym entry to
1223 determine the address it must put in the global offset table, so
1224 both the dynamic object and the regular object will refer to the
1225 same memory location for the variable. */
1226
1227 htab = elf64_x86_64_hash_table (info);
1228
1229 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
1230 to copy the initial value out of the dynamic object and into the
1231 runtime process image. */
1232 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1233 {
1234 htab->srelbss->size += sizeof (Elf64_External_Rela);
1235 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
1236 }
1237
1238 /* We need to figure out the alignment required for this symbol. I
1239 have no idea how ELF linkers handle this. 16-bytes is the size
1240 of the largest type that requires hard alignment -- long double. */
1241 /* FIXME: This is VERY ugly. Should be fixed for all architectures using
1242 this construct. */
1243 power_of_two = bfd_log2 (h->size);
1244 if (power_of_two > 4)
1245 power_of_two = 4;
1246
1247 /* Apply the required alignment. */
1248 s = htab->sdynbss;
1249 s->size = BFD_ALIGN (s->size, (bfd_size_type) (1 << power_of_two));
1250 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1251 {
1252 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1253 return FALSE;
1254 }
1255
1256 /* Define the symbol as being at this point in the section. */
1257 h->root.u.def.section = s;
1258 h->root.u.def.value = s->size;
1259
1260 /* Increment the section size to make room for the symbol. */
1261 s->size += h->size;
1262
1263 return TRUE;
1264 }
1265
1266 /* Allocate space in .plt, .got and associated reloc sections for
1267 dynamic relocs. */
1268
1269 static bfd_boolean
1270 allocate_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1271 {
1272 struct bfd_link_info *info;
1273 struct elf64_x86_64_link_hash_table *htab;
1274 struct elf64_x86_64_link_hash_entry *eh;
1275 struct elf64_x86_64_dyn_relocs *p;
1276
1277 if (h->root.type == bfd_link_hash_indirect)
1278 return TRUE;
1279
1280 if (h->root.type == bfd_link_hash_warning)
1281 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1282
1283 info = (struct bfd_link_info *) inf;
1284 htab = elf64_x86_64_hash_table (info);
1285
1286 if (htab->elf.dynamic_sections_created
1287 && h->plt.refcount > 0)
1288 {
1289 /* Make sure this symbol is output as a dynamic symbol.
1290 Undefined weak syms won't yet be marked as dynamic. */
1291 if (h->dynindx == -1
1292 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1293 {
1294 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1295 return FALSE;
1296 }
1297
1298 if (info->shared
1299 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
1300 {
1301 asection *s = htab->splt;
1302
1303 /* If this is the first .plt entry, make room for the special
1304 first entry. */
1305 if (s->size == 0)
1306 s->size += PLT_ENTRY_SIZE;
1307
1308 h->plt.offset = s->size;
1309
1310 /* If this symbol is not defined in a regular file, and we are
1311 not generating a shared library, then set the symbol to this
1312 location in the .plt. This is required to make function
1313 pointers compare as equal between the normal executable and
1314 the shared library. */
1315 if (! info->shared
1316 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1317 {
1318 h->root.u.def.section = s;
1319 h->root.u.def.value = h->plt.offset;
1320 }
1321
1322 /* Make room for this entry. */
1323 s->size += PLT_ENTRY_SIZE;
1324
1325 /* We also need to make an entry in the .got.plt section, which
1326 will be placed in the .got section by the linker script. */
1327 htab->sgotplt->size += GOT_ENTRY_SIZE;
1328
1329 /* We also need to make an entry in the .rela.plt section. */
1330 htab->srelplt->size += sizeof (Elf64_External_Rela);
1331 }
1332 else
1333 {
1334 h->plt.offset = (bfd_vma) -1;
1335 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1336 }
1337 }
1338 else
1339 {
1340 h->plt.offset = (bfd_vma) -1;
1341 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1342 }
1343
1344 /* If R_X86_64_GOTTPOFF symbol is now local to the binary,
1345 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
1346 if (h->got.refcount > 0
1347 && !info->shared
1348 && h->dynindx == -1
1349 && elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
1350 h->got.offset = (bfd_vma) -1;
1351 else if (h->got.refcount > 0)
1352 {
1353 asection *s;
1354 bfd_boolean dyn;
1355 int tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1356
1357 /* Make sure this symbol is output as a dynamic symbol.
1358 Undefined weak syms won't yet be marked as dynamic. */
1359 if (h->dynindx == -1
1360 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1361 {
1362 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1363 return FALSE;
1364 }
1365
1366 s = htab->sgot;
1367 h->got.offset = s->size;
1368 s->size += GOT_ENTRY_SIZE;
1369 /* R_X86_64_TLSGD needs 2 consecutive GOT slots. */
1370 if (tls_type == GOT_TLS_GD)
1371 s->size += GOT_ENTRY_SIZE;
1372 dyn = htab->elf.dynamic_sections_created;
1373 /* R_X86_64_TLSGD needs one dynamic relocation if local symbol
1374 and two if global.
1375 R_X86_64_GOTTPOFF needs one dynamic relocation. */
1376 if ((tls_type == GOT_TLS_GD && h->dynindx == -1)
1377 || tls_type == GOT_TLS_IE)
1378 htab->srelgot->size += sizeof (Elf64_External_Rela);
1379 else if (tls_type == GOT_TLS_GD)
1380 htab->srelgot->size += 2 * sizeof (Elf64_External_Rela);
1381 else if ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1382 || h->root.type != bfd_link_hash_undefweak)
1383 && (info->shared
1384 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
1385 htab->srelgot->size += sizeof (Elf64_External_Rela);
1386 }
1387 else
1388 h->got.offset = (bfd_vma) -1;
1389
1390 eh = (struct elf64_x86_64_link_hash_entry *) h;
1391 if (eh->dyn_relocs == NULL)
1392 return TRUE;
1393
1394 /* In the shared -Bsymbolic case, discard space allocated for
1395 dynamic pc-relative relocs against symbols which turn out to be
1396 defined in regular objects. For the normal shared case, discard
1397 space for pc-relative relocs that have become local due to symbol
1398 visibility changes. */
1399
1400 if (info->shared)
1401 {
1402 /* Relocs that use pc_count are those that appear on a call
1403 insn, or certain REL relocs that can generated via assembly.
1404 We want calls to protected symbols to resolve directly to the
1405 function rather than going via the plt. If people want
1406 function pointer comparisons to work as expected then they
1407 should avoid writing weird assembly. */
1408 if (SYMBOL_CALLS_LOCAL (info, h))
1409 {
1410 struct elf64_x86_64_dyn_relocs **pp;
1411
1412 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1413 {
1414 p->count -= p->pc_count;
1415 p->pc_count = 0;
1416 if (p->count == 0)
1417 *pp = p->next;
1418 else
1419 pp = &p->next;
1420 }
1421 }
1422
1423 /* Also discard relocs on undefined weak syms with non-default
1424 visibility. */
1425 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1426 && h->root.type == bfd_link_hash_undefweak)
1427 eh->dyn_relocs = NULL;
1428 }
1429 else if (ELIMINATE_COPY_RELOCS)
1430 {
1431 /* For the non-shared case, discard space for relocs against
1432 symbols which turn out to need copy relocs or are not
1433 dynamic. */
1434
1435 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1436 && (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1437 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1438 || (htab->elf.dynamic_sections_created
1439 && (h->root.type == bfd_link_hash_undefweak
1440 || h->root.type == bfd_link_hash_undefined))))
1441 {
1442 /* Make sure this symbol is output as a dynamic symbol.
1443 Undefined weak syms won't yet be marked as dynamic. */
1444 if (h->dynindx == -1
1445 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1446 {
1447 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1448 return FALSE;
1449 }
1450
1451 /* If that succeeded, we know we'll be keeping all the
1452 relocs. */
1453 if (h->dynindx != -1)
1454 goto keep;
1455 }
1456
1457 eh->dyn_relocs = NULL;
1458
1459 keep: ;
1460 }
1461
1462 /* Finally, allocate space. */
1463 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1464 {
1465 asection *sreloc = elf_section_data (p->sec)->sreloc;
1466 sreloc->size += p->count * sizeof (Elf64_External_Rela);
1467 }
1468
1469 return TRUE;
1470 }
1471
1472 /* Find any dynamic relocs that apply to read-only sections. */
1473
1474 static bfd_boolean
1475 readonly_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1476 {
1477 struct elf64_x86_64_link_hash_entry *eh;
1478 struct elf64_x86_64_dyn_relocs *p;
1479
1480 if (h->root.type == bfd_link_hash_warning)
1481 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1482
1483 eh = (struct elf64_x86_64_link_hash_entry *) h;
1484 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1485 {
1486 asection *s = p->sec->output_section;
1487
1488 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1489 {
1490 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1491
1492 info->flags |= DF_TEXTREL;
1493
1494 /* Not an error, just cut short the traversal. */
1495 return FALSE;
1496 }
1497 }
1498 return TRUE;
1499 }
1500
1501 /* Set the sizes of the dynamic sections. */
1502
1503 static bfd_boolean
1504 elf64_x86_64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
1505 struct bfd_link_info *info)
1506 {
1507 struct elf64_x86_64_link_hash_table *htab;
1508 bfd *dynobj;
1509 asection *s;
1510 bfd_boolean relocs;
1511 bfd *ibfd;
1512
1513 htab = elf64_x86_64_hash_table (info);
1514 dynobj = htab->elf.dynobj;
1515 if (dynobj == NULL)
1516 abort ();
1517
1518 if (htab->elf.dynamic_sections_created)
1519 {
1520 /* Set the contents of the .interp section to the interpreter. */
1521 if (info->executable)
1522 {
1523 s = bfd_get_section_by_name (dynobj, ".interp");
1524 if (s == NULL)
1525 abort ();
1526 s->size = sizeof ELF_DYNAMIC_INTERPRETER;
1527 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1528 }
1529 }
1530
1531 /* Set up .got offsets for local syms, and space for local dynamic
1532 relocs. */
1533 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1534 {
1535 bfd_signed_vma *local_got;
1536 bfd_signed_vma *end_local_got;
1537 char *local_tls_type;
1538 bfd_size_type locsymcount;
1539 Elf_Internal_Shdr *symtab_hdr;
1540 asection *srel;
1541
1542 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1543 continue;
1544
1545 for (s = ibfd->sections; s != NULL; s = s->next)
1546 {
1547 struct elf64_x86_64_dyn_relocs *p;
1548
1549 for (p = *((struct elf64_x86_64_dyn_relocs **)
1550 &elf_section_data (s)->local_dynrel);
1551 p != NULL;
1552 p = p->next)
1553 {
1554 if (!bfd_is_abs_section (p->sec)
1555 && bfd_is_abs_section (p->sec->output_section))
1556 {
1557 /* Input section has been discarded, either because
1558 it is a copy of a linkonce section or due to
1559 linker script /DISCARD/, so we'll be discarding
1560 the relocs too. */
1561 }
1562 else if (p->count != 0)
1563 {
1564 srel = elf_section_data (p->sec)->sreloc;
1565 srel->size += p->count * sizeof (Elf64_External_Rela);
1566 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1567 info->flags |= DF_TEXTREL;
1568
1569 }
1570 }
1571 }
1572
1573 local_got = elf_local_got_refcounts (ibfd);
1574 if (!local_got)
1575 continue;
1576
1577 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1578 locsymcount = symtab_hdr->sh_info;
1579 end_local_got = local_got + locsymcount;
1580 local_tls_type = elf64_x86_64_local_got_tls_type (ibfd);
1581 s = htab->sgot;
1582 srel = htab->srelgot;
1583 for (; local_got < end_local_got; ++local_got, ++local_tls_type)
1584 {
1585 if (*local_got > 0)
1586 {
1587 *local_got = s->size;
1588 s->size += GOT_ENTRY_SIZE;
1589 if (*local_tls_type == GOT_TLS_GD)
1590 s->size += GOT_ENTRY_SIZE;
1591 if (info->shared
1592 || *local_tls_type == GOT_TLS_GD
1593 || *local_tls_type == GOT_TLS_IE)
1594 srel->size += sizeof (Elf64_External_Rela);
1595 }
1596 else
1597 *local_got = (bfd_vma) -1;
1598 }
1599 }
1600
1601 if (htab->tls_ld_got.refcount > 0)
1602 {
1603 /* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD
1604 relocs. */
1605 htab->tls_ld_got.offset = htab->sgot->size;
1606 htab->sgot->size += 2 * GOT_ENTRY_SIZE;
1607 htab->srelgot->size += sizeof (Elf64_External_Rela);
1608 }
1609 else
1610 htab->tls_ld_got.offset = -1;
1611
1612 /* Allocate global sym .plt and .got entries, and space for global
1613 sym dynamic relocs. */
1614 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1615
1616 /* We now have determined the sizes of the various dynamic sections.
1617 Allocate memory for them. */
1618 relocs = FALSE;
1619 for (s = dynobj->sections; s != NULL; s = s->next)
1620 {
1621 if ((s->flags & SEC_LINKER_CREATED) == 0)
1622 continue;
1623
1624 if (s == htab->splt
1625 || s == htab->sgot
1626 || s == htab->sgotplt)
1627 {
1628 /* Strip this section if we don't need it; see the
1629 comment below. */
1630 }
1631 else if (strncmp (bfd_get_section_name (dynobj, s), ".rela", 5) == 0)
1632 {
1633 if (s->size != 0 && s != htab->srelplt)
1634 relocs = TRUE;
1635
1636 /* We use the reloc_count field as a counter if we need
1637 to copy relocs into the output file. */
1638 s->reloc_count = 0;
1639 }
1640 else
1641 {
1642 /* It's not one of our sections, so don't allocate space. */
1643 continue;
1644 }
1645
1646 if (s->size == 0)
1647 {
1648 /* If we don't need this section, strip it from the
1649 output file. This is mostly to handle .rela.bss and
1650 .rela.plt. We must create both sections in
1651 create_dynamic_sections, because they must be created
1652 before the linker maps input sections to output
1653 sections. The linker does that before
1654 adjust_dynamic_symbol is called, and it is that
1655 function which decides whether anything needs to go
1656 into these sections. */
1657
1658 _bfd_strip_section_from_output (info, s);
1659 continue;
1660 }
1661
1662 /* Allocate memory for the section contents. We use bfd_zalloc
1663 here in case unused entries are not reclaimed before the
1664 section's contents are written out. This should not happen,
1665 but this way if it does, we get a R_X86_64_NONE reloc instead
1666 of garbage. */
1667 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->size);
1668 if (s->contents == NULL)
1669 return FALSE;
1670 }
1671
1672 if (htab->elf.dynamic_sections_created)
1673 {
1674 /* Add some entries to the .dynamic section. We fill in the
1675 values later, in elf64_x86_64_finish_dynamic_sections, but we
1676 must add the entries now so that we get the correct size for
1677 the .dynamic section. The DT_DEBUG entry is filled in by the
1678 dynamic linker and used by the debugger. */
1679 #define add_dynamic_entry(TAG, VAL) \
1680 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1681
1682 if (info->executable)
1683 {
1684 if (!add_dynamic_entry (DT_DEBUG, 0))
1685 return FALSE;
1686 }
1687
1688 if (htab->splt->size != 0)
1689 {
1690 if (!add_dynamic_entry (DT_PLTGOT, 0)
1691 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1692 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1693 || !add_dynamic_entry (DT_JMPREL, 0))
1694 return FALSE;
1695 }
1696
1697 if (relocs)
1698 {
1699 if (!add_dynamic_entry (DT_RELA, 0)
1700 || !add_dynamic_entry (DT_RELASZ, 0)
1701 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
1702 return FALSE;
1703
1704 /* If any dynamic relocs apply to a read-only section,
1705 then we need a DT_TEXTREL entry. */
1706 if ((info->flags & DF_TEXTREL) == 0)
1707 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
1708 (PTR) info);
1709
1710 if ((info->flags & DF_TEXTREL) != 0)
1711 {
1712 if (!add_dynamic_entry (DT_TEXTREL, 0))
1713 return FALSE;
1714 }
1715 }
1716 }
1717 #undef add_dynamic_entry
1718
1719 return TRUE;
1720 }
1721
1722 /* Return the base VMA address which should be subtracted from real addresses
1723 when resolving @dtpoff relocation.
1724 This is PT_TLS segment p_vaddr. */
1725
1726 static bfd_vma
1727 dtpoff_base (struct bfd_link_info *info)
1728 {
1729 /* If tls_sec is NULL, we should have signalled an error already. */
1730 if (elf_hash_table (info)->tls_sec == NULL)
1731 return 0;
1732 return elf_hash_table (info)->tls_sec->vma;
1733 }
1734
1735 /* Return the relocation value for @tpoff relocation
1736 if STT_TLS virtual address is ADDRESS. */
1737
1738 static bfd_vma
1739 tpoff (struct bfd_link_info *info, bfd_vma address)
1740 {
1741 struct elf_link_hash_table *htab = elf_hash_table (info);
1742
1743 /* If tls_segment is NULL, we should have signalled an error already. */
1744 if (htab->tls_sec == NULL)
1745 return 0;
1746 return address - htab->tls_size - htab->tls_sec->vma;
1747 }
1748
1749 /* Relocate an x86_64 ELF section. */
1750
1751 static bfd_boolean
1752 elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
1753 bfd *input_bfd, asection *input_section,
1754 bfd_byte *contents, Elf_Internal_Rela *relocs,
1755 Elf_Internal_Sym *local_syms,
1756 asection **local_sections)
1757 {
1758 struct elf64_x86_64_link_hash_table *htab;
1759 Elf_Internal_Shdr *symtab_hdr;
1760 struct elf_link_hash_entry **sym_hashes;
1761 bfd_vma *local_got_offsets;
1762 Elf_Internal_Rela *rel;
1763 Elf_Internal_Rela *relend;
1764
1765 if (info->relocatable)
1766 return TRUE;
1767
1768 htab = elf64_x86_64_hash_table (info);
1769 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1770 sym_hashes = elf_sym_hashes (input_bfd);
1771 local_got_offsets = elf_local_got_offsets (input_bfd);
1772
1773 rel = relocs;
1774 relend = relocs + input_section->reloc_count;
1775 for (; rel < relend; rel++)
1776 {
1777 unsigned int r_type;
1778 reloc_howto_type *howto;
1779 unsigned long r_symndx;
1780 struct elf_link_hash_entry *h;
1781 Elf_Internal_Sym *sym;
1782 asection *sec;
1783 bfd_vma off;
1784 bfd_vma relocation;
1785 bfd_boolean unresolved_reloc;
1786 bfd_reloc_status_type r;
1787 int tls_type;
1788
1789 r_type = ELF64_R_TYPE (rel->r_info);
1790 if (r_type == (int) R_X86_64_GNU_VTINHERIT
1791 || r_type == (int) R_X86_64_GNU_VTENTRY)
1792 continue;
1793
1794 if (r_type >= R_X86_64_max)
1795 {
1796 bfd_set_error (bfd_error_bad_value);
1797 return FALSE;
1798 }
1799
1800 howto = x86_64_elf_howto_table + r_type;
1801 r_symndx = ELF64_R_SYM (rel->r_info);
1802 h = NULL;
1803 sym = NULL;
1804 sec = NULL;
1805 unresolved_reloc = FALSE;
1806 if (r_symndx < symtab_hdr->sh_info)
1807 {
1808 sym = local_syms + r_symndx;
1809 sec = local_sections[r_symndx];
1810
1811 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
1812 }
1813 else
1814 {
1815 bfd_boolean warned;
1816
1817 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
1818 r_symndx, symtab_hdr, sym_hashes,
1819 h, sec, relocation,
1820 unresolved_reloc, warned);
1821 }
1822 /* When generating a shared object, the relocations handled here are
1823 copied into the output file to be resolved at run time. */
1824 switch (r_type)
1825 {
1826 case R_X86_64_GOT32:
1827 /* Relocation is to the entry for this symbol in the global
1828 offset table. */
1829 case R_X86_64_GOTPCREL:
1830 /* Use global offset table as symbol value. */
1831 if (htab->sgot == NULL)
1832 abort ();
1833
1834 if (h != NULL)
1835 {
1836 bfd_boolean dyn;
1837
1838 off = h->got.offset;
1839 dyn = htab->elf.dynamic_sections_created;
1840
1841 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
1842 || (info->shared
1843 && SYMBOL_REFERENCES_LOCAL (info, h))
1844 || (ELF_ST_VISIBILITY (h->other)
1845 && h->root.type == bfd_link_hash_undefweak))
1846 {
1847 /* This is actually a static link, or it is a -Bsymbolic
1848 link and the symbol is defined locally, or the symbol
1849 was forced to be local because of a version file. We
1850 must initialize this entry in the global offset table.
1851 Since the offset must always be a multiple of 8, we
1852 use the least significant bit to record whether we
1853 have initialized it already.
1854
1855 When doing a dynamic link, we create a .rela.got
1856 relocation entry to initialize the value. This is
1857 done in the finish_dynamic_symbol routine. */
1858 if ((off & 1) != 0)
1859 off &= ~1;
1860 else
1861 {
1862 bfd_put_64 (output_bfd, relocation,
1863 htab->sgot->contents + off);
1864 h->got.offset |= 1;
1865 }
1866 }
1867 else
1868 unresolved_reloc = FALSE;
1869 }
1870 else
1871 {
1872 if (local_got_offsets == NULL)
1873 abort ();
1874
1875 off = local_got_offsets[r_symndx];
1876
1877 /* The offset must always be a multiple of 8. We use
1878 the least significant bit to record whether we have
1879 already generated the necessary reloc. */
1880 if ((off & 1) != 0)
1881 off &= ~1;
1882 else
1883 {
1884 bfd_put_64 (output_bfd, relocation,
1885 htab->sgot->contents + off);
1886
1887 if (info->shared)
1888 {
1889 asection *s;
1890 Elf_Internal_Rela outrel;
1891 bfd_byte *loc;
1892
1893 /* We need to generate a R_X86_64_RELATIVE reloc
1894 for the dynamic linker. */
1895 s = htab->srelgot;
1896 if (s == NULL)
1897 abort ();
1898
1899 outrel.r_offset = (htab->sgot->output_section->vma
1900 + htab->sgot->output_offset
1901 + off);
1902 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
1903 outrel.r_addend = relocation;
1904 loc = s->contents;
1905 loc += s->reloc_count++ * sizeof (Elf64_External_Rela);
1906 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
1907 }
1908
1909 local_got_offsets[r_symndx] |= 1;
1910 }
1911 }
1912
1913 if (off >= (bfd_vma) -2)
1914 abort ();
1915
1916 relocation = htab->sgot->output_section->vma
1917 + htab->sgot->output_offset + off;
1918 if (r_type != R_X86_64_GOTPCREL)
1919 relocation -= htab->sgotplt->output_section->vma
1920 - htab->sgotplt->output_offset;
1921
1922 break;
1923
1924 case R_X86_64_PLT32:
1925 /* Relocation is to the entry for this symbol in the
1926 procedure linkage table. */
1927
1928 /* Resolve a PLT32 reloc against a local symbol directly,
1929 without using the procedure linkage table. */
1930 if (h == NULL)
1931 break;
1932
1933 if (h->plt.offset == (bfd_vma) -1
1934 || htab->splt == NULL)
1935 {
1936 /* We didn't make a PLT entry for this symbol. This
1937 happens when statically linking PIC code, or when
1938 using -Bsymbolic. */
1939 break;
1940 }
1941
1942 relocation = (htab->splt->output_section->vma
1943 + htab->splt->output_offset
1944 + h->plt.offset);
1945 unresolved_reloc = FALSE;
1946 break;
1947
1948 case R_X86_64_PC8:
1949 case R_X86_64_PC16:
1950 case R_X86_64_PC32:
1951 if (info->shared
1952 && !SYMBOL_REFERENCES_LOCAL (info, h)
1953 && (sec->flags & SEC_ALLOC) != 0
1954 && (sec->flags & SEC_READONLY) != 0)
1955 {
1956 (*_bfd_error_handler)
1957 (_("%s: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
1958 bfd_archive_filename (input_bfd),
1959 x86_64_elf_howto_table[r_type].name,
1960 (h) ? h->root.root.string : "a local symbol");
1961 bfd_set_error (bfd_error_bad_value);
1962 return FALSE;
1963 }
1964 /* Fall through. */
1965
1966 case R_X86_64_8:
1967 case R_X86_64_16:
1968 case R_X86_64_32:
1969 case R_X86_64_64:
1970 /* FIXME: The ABI says the linker should make sure the value is
1971 the same when it's zeroextended to 64 bit. */
1972
1973 /* r_symndx will be zero only for relocs against symbols
1974 from removed linkonce sections, or sections discarded by
1975 a linker script. */
1976 if (r_symndx == 0
1977 || (input_section->flags & SEC_ALLOC) == 0)
1978 break;
1979
1980 if ((info->shared
1981 && (h == NULL
1982 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1983 || h->root.type != bfd_link_hash_undefweak)
1984 && ((r_type != R_X86_64_PC8
1985 && r_type != R_X86_64_PC16
1986 && r_type != R_X86_64_PC32)
1987 || !SYMBOL_CALLS_LOCAL (info, h)))
1988 || (ELIMINATE_COPY_RELOCS
1989 && !info->shared
1990 && h != NULL
1991 && h->dynindx != -1
1992 && (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1993 && (((h->elf_link_hash_flags
1994 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1995 && (h->elf_link_hash_flags
1996 & ELF_LINK_HASH_DEF_REGULAR) == 0)
1997 || h->root.type == bfd_link_hash_undefweak
1998 || h->root.type == bfd_link_hash_undefined)))
1999 {
2000 Elf_Internal_Rela outrel;
2001 bfd_byte *loc;
2002 bfd_boolean skip, relocate;
2003 asection *sreloc;
2004
2005 /* When generating a shared object, these relocations
2006 are copied into the output file to be resolved at run
2007 time. */
2008 skip = FALSE;
2009 relocate = FALSE;
2010
2011 outrel.r_offset =
2012 _bfd_elf_section_offset (output_bfd, info, input_section,
2013 rel->r_offset);
2014 if (outrel.r_offset == (bfd_vma) -1)
2015 skip = TRUE;
2016 else if (outrel.r_offset == (bfd_vma) -2)
2017 skip = TRUE, relocate = TRUE;
2018
2019 outrel.r_offset += (input_section->output_section->vma
2020 + input_section->output_offset);
2021
2022 if (skip)
2023 memset (&outrel, 0, sizeof outrel);
2024
2025 /* h->dynindx may be -1 if this symbol was marked to
2026 become local. */
2027 else if (h != NULL
2028 && h->dynindx != -1
2029 && (r_type == R_X86_64_PC8
2030 || r_type == R_X86_64_PC16
2031 || r_type == R_X86_64_PC32
2032 || !info->shared
2033 || !info->symbolic
2034 || (h->elf_link_hash_flags
2035 & ELF_LINK_HASH_DEF_REGULAR) == 0))
2036 {
2037 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
2038 outrel.r_addend = rel->r_addend;
2039 }
2040 else
2041 {
2042 /* This symbol is local, or marked to become local. */
2043 if (r_type == R_X86_64_64)
2044 {
2045 relocate = TRUE;
2046 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2047 outrel.r_addend = relocation + rel->r_addend;
2048 }
2049 else
2050 {
2051 long sindx;
2052
2053 if (bfd_is_abs_section (sec))
2054 sindx = 0;
2055 else if (sec == NULL || sec->owner == NULL)
2056 {
2057 bfd_set_error (bfd_error_bad_value);
2058 return FALSE;
2059 }
2060 else
2061 {
2062 asection *osec;
2063
2064 osec = sec->output_section;
2065 sindx = elf_section_data (osec)->dynindx;
2066 BFD_ASSERT (sindx > 0);
2067 }
2068
2069 outrel.r_info = ELF64_R_INFO (sindx, r_type);
2070 outrel.r_addend = relocation + rel->r_addend;
2071 }
2072 }
2073
2074 sreloc = elf_section_data (input_section)->sreloc;
2075 if (sreloc == NULL)
2076 abort ();
2077
2078 loc = sreloc->contents;
2079 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
2080 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2081
2082 /* If this reloc is against an external symbol, we do
2083 not want to fiddle with the addend. Otherwise, we
2084 need to include the symbol value so that it becomes
2085 an addend for the dynamic reloc. */
2086 if (! relocate)
2087 continue;
2088 }
2089
2090 break;
2091
2092 case R_X86_64_TLSGD:
2093 case R_X86_64_GOTTPOFF:
2094 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
2095 tls_type = GOT_UNKNOWN;
2096 if (h == NULL && local_got_offsets)
2097 tls_type = elf64_x86_64_local_got_tls_type (input_bfd) [r_symndx];
2098 else if (h != NULL)
2099 {
2100 tls_type = elf64_x86_64_hash_entry (h)->tls_type;
2101 if (!info->shared && h->dynindx == -1 && tls_type == GOT_TLS_IE)
2102 r_type = R_X86_64_TPOFF32;
2103 }
2104 if (r_type == R_X86_64_TLSGD)
2105 {
2106 if (tls_type == GOT_TLS_IE)
2107 r_type = R_X86_64_GOTTPOFF;
2108 }
2109
2110 if (r_type == R_X86_64_TPOFF32)
2111 {
2112 BFD_ASSERT (! unresolved_reloc);
2113 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
2114 {
2115 unsigned int i;
2116 static unsigned char tlsgd[8]
2117 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2118
2119 /* GD->LE transition.
2120 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2121 .word 0x6666; rex64; call __tls_get_addr@plt
2122 Change it into:
2123 movq %fs:0, %rax
2124 leaq foo@tpoff(%rax), %rax */
2125 BFD_ASSERT (rel->r_offset >= 4);
2126 for (i = 0; i < 4; i++)
2127 BFD_ASSERT (bfd_get_8 (input_bfd,
2128 contents + rel->r_offset - 4 + i)
2129 == tlsgd[i]);
2130 BFD_ASSERT (rel->r_offset + 12 <= input_section->size);
2131 for (i = 0; i < 4; i++)
2132 BFD_ASSERT (bfd_get_8 (input_bfd,
2133 contents + rel->r_offset + 4 + i)
2134 == tlsgd[i+4]);
2135 BFD_ASSERT (rel + 1 < relend);
2136 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2137 memcpy (contents + rel->r_offset - 4,
2138 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0",
2139 16);
2140 bfd_put_32 (output_bfd, tpoff (info, relocation),
2141 contents + rel->r_offset + 8);
2142 /* Skip R_X86_64_PLT32. */
2143 rel++;
2144 continue;
2145 }
2146 else
2147 {
2148 unsigned int val, type, reg;
2149
2150 /* IE->LE transition:
2151 Originally it can be one of:
2152 movq foo@gottpoff(%rip), %reg
2153 addq foo@gottpoff(%rip), %reg
2154 We change it into:
2155 movq $foo, %reg
2156 leaq foo(%reg), %reg
2157 addq $foo, %reg. */
2158 BFD_ASSERT (rel->r_offset >= 3);
2159 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 3);
2160 BFD_ASSERT (val == 0x48 || val == 0x4c);
2161 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2162 BFD_ASSERT (type == 0x8b || type == 0x03);
2163 reg = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2164 BFD_ASSERT ((reg & 0xc7) == 5);
2165 reg >>= 3;
2166 BFD_ASSERT (rel->r_offset + 4 <= input_section->size);
2167 if (type == 0x8b)
2168 {
2169 /* movq */
2170 if (val == 0x4c)
2171 bfd_put_8 (output_bfd, 0x49,
2172 contents + rel->r_offset - 3);
2173 bfd_put_8 (output_bfd, 0xc7,
2174 contents + rel->r_offset - 2);
2175 bfd_put_8 (output_bfd, 0xc0 | reg,
2176 contents + rel->r_offset - 1);
2177 }
2178 else if (reg == 4)
2179 {
2180 /* addq -> addq - addressing with %rsp/%r12 is
2181 special */
2182 if (val == 0x4c)
2183 bfd_put_8 (output_bfd, 0x49,
2184 contents + rel->r_offset - 3);
2185 bfd_put_8 (output_bfd, 0x81,
2186 contents + rel->r_offset - 2);
2187 bfd_put_8 (output_bfd, 0xc0 | reg,
2188 contents + rel->r_offset - 1);
2189 }
2190 else
2191 {
2192 /* addq -> leaq */
2193 if (val == 0x4c)
2194 bfd_put_8 (output_bfd, 0x4d,
2195 contents + rel->r_offset - 3);
2196 bfd_put_8 (output_bfd, 0x8d,
2197 contents + rel->r_offset - 2);
2198 bfd_put_8 (output_bfd, 0x80 | reg | (reg << 3),
2199 contents + rel->r_offset - 1);
2200 }
2201 bfd_put_32 (output_bfd, tpoff (info, relocation),
2202 contents + rel->r_offset);
2203 continue;
2204 }
2205 }
2206
2207 if (htab->sgot == NULL)
2208 abort ();
2209
2210 if (h != NULL)
2211 off = h->got.offset;
2212 else
2213 {
2214 if (local_got_offsets == NULL)
2215 abort ();
2216
2217 off = local_got_offsets[r_symndx];
2218 }
2219
2220 if ((off & 1) != 0)
2221 off &= ~1;
2222 else
2223 {
2224 Elf_Internal_Rela outrel;
2225 bfd_byte *loc;
2226 int dr_type, indx;
2227
2228 if (htab->srelgot == NULL)
2229 abort ();
2230
2231 outrel.r_offset = (htab->sgot->output_section->vma
2232 + htab->sgot->output_offset + off);
2233
2234 indx = h && h->dynindx != -1 ? h->dynindx : 0;
2235 if (r_type == R_X86_64_TLSGD)
2236 dr_type = R_X86_64_DTPMOD64;
2237 else
2238 dr_type = R_X86_64_TPOFF64;
2239
2240 bfd_put_64 (output_bfd, 0, htab->sgot->contents + off);
2241 outrel.r_addend = 0;
2242 if (dr_type == R_X86_64_TPOFF64 && indx == 0)
2243 outrel.r_addend = relocation - dtpoff_base (info);
2244 outrel.r_info = ELF64_R_INFO (indx, dr_type);
2245
2246 loc = htab->srelgot->contents;
2247 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2248 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2249
2250 if (r_type == R_X86_64_TLSGD)
2251 {
2252 if (indx == 0)
2253 {
2254 BFD_ASSERT (! unresolved_reloc);
2255 bfd_put_64 (output_bfd,
2256 relocation - dtpoff_base (info),
2257 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2258 }
2259 else
2260 {
2261 bfd_put_64 (output_bfd, 0,
2262 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2263 outrel.r_info = ELF64_R_INFO (indx,
2264 R_X86_64_DTPOFF64);
2265 outrel.r_offset += GOT_ENTRY_SIZE;
2266 htab->srelgot->reloc_count++;
2267 loc += sizeof (Elf64_External_Rela);
2268 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2269 }
2270 }
2271
2272 if (h != NULL)
2273 h->got.offset |= 1;
2274 else
2275 local_got_offsets[r_symndx] |= 1;
2276 }
2277
2278 if (off >= (bfd_vma) -2)
2279 abort ();
2280 if (r_type == ELF64_R_TYPE (rel->r_info))
2281 {
2282 relocation = htab->sgot->output_section->vma
2283 + htab->sgot->output_offset + off;
2284 unresolved_reloc = FALSE;
2285 }
2286 else
2287 {
2288 unsigned int i;
2289 static unsigned char tlsgd[8]
2290 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2291
2292 /* GD->IE transition.
2293 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2294 .word 0x6666; rex64; call __tls_get_addr@plt
2295 Change it into:
2296 movq %fs:0, %rax
2297 addq foo@gottpoff(%rip), %rax */
2298 BFD_ASSERT (rel->r_offset >= 4);
2299 for (i = 0; i < 4; i++)
2300 BFD_ASSERT (bfd_get_8 (input_bfd,
2301 contents + rel->r_offset - 4 + i)
2302 == tlsgd[i]);
2303 BFD_ASSERT (rel->r_offset + 12 <= input_section->size);
2304 for (i = 0; i < 4; i++)
2305 BFD_ASSERT (bfd_get_8 (input_bfd,
2306 contents + rel->r_offset + 4 + i)
2307 == tlsgd[i+4]);
2308 BFD_ASSERT (rel + 1 < relend);
2309 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2310 memcpy (contents + rel->r_offset - 4,
2311 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0",
2312 16);
2313
2314 relocation = (htab->sgot->output_section->vma
2315 + htab->sgot->output_offset + off
2316 - rel->r_offset
2317 - input_section->output_section->vma
2318 - input_section->output_offset
2319 - 12);
2320 bfd_put_32 (output_bfd, relocation,
2321 contents + rel->r_offset + 8);
2322 /* Skip R_X86_64_PLT32. */
2323 rel++;
2324 continue;
2325 }
2326 break;
2327
2328 case R_X86_64_TLSLD:
2329 if (! info->shared)
2330 {
2331 /* LD->LE transition:
2332 Ensure it is:
2333 leaq foo@tlsld(%rip), %rdi; call __tls_get_addr@plt.
2334 We change it into:
2335 .word 0x6666; .byte 0x66; movl %fs:0, %rax. */
2336 BFD_ASSERT (rel->r_offset >= 3);
2337 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 3)
2338 == 0x48);
2339 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 2)
2340 == 0x8d);
2341 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 1)
2342 == 0x3d);
2343 BFD_ASSERT (rel->r_offset + 9 <= input_section->size);
2344 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2345 == 0xe8);
2346 BFD_ASSERT (rel + 1 < relend);
2347 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2348 memcpy (contents + rel->r_offset - 3,
2349 "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0", 12);
2350 /* Skip R_X86_64_PLT32. */
2351 rel++;
2352 continue;
2353 }
2354
2355 if (htab->sgot == NULL)
2356 abort ();
2357
2358 off = htab->tls_ld_got.offset;
2359 if (off & 1)
2360 off &= ~1;
2361 else
2362 {
2363 Elf_Internal_Rela outrel;
2364 bfd_byte *loc;
2365
2366 if (htab->srelgot == NULL)
2367 abort ();
2368
2369 outrel.r_offset = (htab->sgot->output_section->vma
2370 + htab->sgot->output_offset + off);
2371
2372 bfd_put_64 (output_bfd, 0,
2373 htab->sgot->contents + off);
2374 bfd_put_64 (output_bfd, 0,
2375 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2376 outrel.r_info = ELF64_R_INFO (0, R_X86_64_DTPMOD64);
2377 outrel.r_addend = 0;
2378 loc = htab->srelgot->contents;
2379 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2380 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2381 htab->tls_ld_got.offset |= 1;
2382 }
2383 relocation = htab->sgot->output_section->vma
2384 + htab->sgot->output_offset + off;
2385 unresolved_reloc = FALSE;
2386 break;
2387
2388 case R_X86_64_DTPOFF32:
2389 if (info->shared || (input_section->flags & SEC_CODE) == 0)
2390 relocation -= dtpoff_base (info);
2391 else
2392 relocation = tpoff (info, relocation);
2393 break;
2394
2395 case R_X86_64_TPOFF32:
2396 BFD_ASSERT (! info->shared);
2397 relocation = tpoff (info, relocation);
2398 break;
2399
2400 default:
2401 break;
2402 }
2403
2404 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
2405 because such sections are not SEC_ALLOC and thus ld.so will
2406 not process them. */
2407 if (unresolved_reloc
2408 && !((input_section->flags & SEC_DEBUGGING) != 0
2409 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
2410 (*_bfd_error_handler)
2411 (_("%s(%s+0x%lx): unresolvable relocation against symbol `%s'"),
2412 bfd_archive_filename (input_bfd),
2413 bfd_get_section_name (input_bfd, input_section),
2414 (long) rel->r_offset,
2415 h->root.root.string);
2416
2417 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
2418 contents, rel->r_offset,
2419 relocation, rel->r_addend);
2420
2421 if (r != bfd_reloc_ok)
2422 {
2423 const char *name;
2424
2425 if (h != NULL)
2426 name = h->root.root.string;
2427 else
2428 {
2429 name = bfd_elf_string_from_elf_section (input_bfd,
2430 symtab_hdr->sh_link,
2431 sym->st_name);
2432 if (name == NULL)
2433 return FALSE;
2434 if (*name == '\0')
2435 name = bfd_section_name (input_bfd, sec);
2436 }
2437
2438 if (r == bfd_reloc_overflow)
2439 {
2440 if (h != NULL
2441 && h->root.type == bfd_link_hash_undefweak
2442 && howto->pc_relative)
2443 /* Ignore reloc overflow on branches to undefweak syms. */
2444 continue;
2445
2446 if (! ((*info->callbacks->reloc_overflow)
2447 (info, name, howto->name, (bfd_vma) 0,
2448 input_bfd, input_section, rel->r_offset)))
2449 return FALSE;
2450 }
2451 else
2452 {
2453 (*_bfd_error_handler)
2454 (_("%s(%s+0x%lx): reloc against `%s': error %d"),
2455 bfd_archive_filename (input_bfd),
2456 bfd_get_section_name (input_bfd, input_section),
2457 (long) rel->r_offset, name, (int) r);
2458 return FALSE;
2459 }
2460 }
2461 }
2462
2463 return TRUE;
2464 }
2465
2466 /* Finish up dynamic symbol handling. We set the contents of various
2467 dynamic sections here. */
2468
2469 static bfd_boolean
2470 elf64_x86_64_finish_dynamic_symbol (bfd *output_bfd,
2471 struct bfd_link_info *info,
2472 struct elf_link_hash_entry *h,
2473 Elf_Internal_Sym *sym)
2474 {
2475 struct elf64_x86_64_link_hash_table *htab;
2476
2477 htab = elf64_x86_64_hash_table (info);
2478
2479 if (h->plt.offset != (bfd_vma) -1)
2480 {
2481 bfd_vma plt_index;
2482 bfd_vma got_offset;
2483 Elf_Internal_Rela rela;
2484 bfd_byte *loc;
2485
2486 /* This symbol has an entry in the procedure linkage table. Set
2487 it up. */
2488 if (h->dynindx == -1
2489 || htab->splt == NULL
2490 || htab->sgotplt == NULL
2491 || htab->srelplt == NULL)
2492 abort ();
2493
2494 /* Get the index in the procedure linkage table which
2495 corresponds to this symbol. This is the index of this symbol
2496 in all the symbols for which we are making plt entries. The
2497 first entry in the procedure linkage table is reserved. */
2498 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2499
2500 /* Get the offset into the .got table of the entry that
2501 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
2502 bytes. The first three are reserved for the dynamic linker. */
2503 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
2504
2505 /* Fill in the entry in the procedure linkage table. */
2506 memcpy (htab->splt->contents + h->plt.offset, elf64_x86_64_plt_entry,
2507 PLT_ENTRY_SIZE);
2508
2509 /* Insert the relocation positions of the plt section. The magic
2510 numbers at the end of the statements are the positions of the
2511 relocations in the plt section. */
2512 /* Put offset for jmp *name@GOTPCREL(%rip), since the
2513 instruction uses 6 bytes, subtract this value. */
2514 bfd_put_32 (output_bfd,
2515 (htab->sgotplt->output_section->vma
2516 + htab->sgotplt->output_offset
2517 + got_offset
2518 - htab->splt->output_section->vma
2519 - htab->splt->output_offset
2520 - h->plt.offset
2521 - 6),
2522 htab->splt->contents + h->plt.offset + 2);
2523 /* Put relocation index. */
2524 bfd_put_32 (output_bfd, plt_index,
2525 htab->splt->contents + h->plt.offset + 7);
2526 /* Put offset for jmp .PLT0. */
2527 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
2528 htab->splt->contents + h->plt.offset + 12);
2529
2530 /* Fill in the entry in the global offset table, initially this
2531 points to the pushq instruction in the PLT which is at offset 6. */
2532 bfd_put_64 (output_bfd, (htab->splt->output_section->vma
2533 + htab->splt->output_offset
2534 + h->plt.offset + 6),
2535 htab->sgotplt->contents + got_offset);
2536
2537 /* Fill in the entry in the .rela.plt section. */
2538 rela.r_offset = (htab->sgotplt->output_section->vma
2539 + htab->sgotplt->output_offset
2540 + got_offset);
2541 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
2542 rela.r_addend = 0;
2543 loc = htab->srelplt->contents + plt_index * sizeof (Elf64_External_Rela);
2544 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2545
2546 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2547 {
2548 /* Mark the symbol as undefined, rather than as defined in
2549 the .plt section. Leave the value if there were any
2550 relocations where pointer equality matters (this is a clue
2551 for the dynamic linker, to make function pointer
2552 comparisons work between an application and shared
2553 library), otherwise set it to zero. If a function is only
2554 called from a binary, there is no need to slow down
2555 shared libraries because of that. */
2556 sym->st_shndx = SHN_UNDEF;
2557 if ((h->elf_link_hash_flags & ELF_LINK_POINTER_EQUALITY_NEEDED) == 0)
2558 sym->st_value = 0;
2559 }
2560 }
2561
2562 if (h->got.offset != (bfd_vma) -1
2563 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_GD
2564 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE)
2565 {
2566 Elf_Internal_Rela rela;
2567 bfd_byte *loc;
2568
2569 /* This symbol has an entry in the global offset table. Set it
2570 up. */
2571 if (htab->sgot == NULL || htab->srelgot == NULL)
2572 abort ();
2573
2574 rela.r_offset = (htab->sgot->output_section->vma
2575 + htab->sgot->output_offset
2576 + (h->got.offset &~ (bfd_vma) 1));
2577
2578 /* If this is a static link, or it is a -Bsymbolic link and the
2579 symbol is defined locally or was forced to be local because
2580 of a version file, we just want to emit a RELATIVE reloc.
2581 The entry in the global offset table will already have been
2582 initialized in the relocate_section function. */
2583 if (info->shared
2584 && SYMBOL_REFERENCES_LOCAL (info, h))
2585 {
2586 BFD_ASSERT((h->got.offset & 1) != 0);
2587 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2588 rela.r_addend = (h->root.u.def.value
2589 + h->root.u.def.section->output_section->vma
2590 + h->root.u.def.section->output_offset);
2591 }
2592 else
2593 {
2594 BFD_ASSERT((h->got.offset & 1) == 0);
2595 bfd_put_64 (output_bfd, (bfd_vma) 0,
2596 htab->sgot->contents + h->got.offset);
2597 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
2598 rela.r_addend = 0;
2599 }
2600
2601 loc = htab->srelgot->contents;
2602 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2603 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2604 }
2605
2606 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
2607 {
2608 Elf_Internal_Rela rela;
2609 bfd_byte *loc;
2610
2611 /* This symbol needs a copy reloc. Set it up. */
2612
2613 if (h->dynindx == -1
2614 || (h->root.type != bfd_link_hash_defined
2615 && h->root.type != bfd_link_hash_defweak)
2616 || htab->srelbss == NULL)
2617 abort ();
2618
2619 rela.r_offset = (h->root.u.def.value
2620 + h->root.u.def.section->output_section->vma
2621 + h->root.u.def.section->output_offset);
2622 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
2623 rela.r_addend = 0;
2624 loc = htab->srelbss->contents;
2625 loc += htab->srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
2626 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2627 }
2628
2629 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
2630 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
2631 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
2632 sym->st_shndx = SHN_ABS;
2633
2634 return TRUE;
2635 }
2636
2637 /* Used to decide how to sort relocs in an optimal manner for the
2638 dynamic linker, before writing them out. */
2639
2640 static enum elf_reloc_type_class
2641 elf64_x86_64_reloc_type_class (const Elf_Internal_Rela *rela)
2642 {
2643 switch ((int) ELF64_R_TYPE (rela->r_info))
2644 {
2645 case R_X86_64_RELATIVE:
2646 return reloc_class_relative;
2647 case R_X86_64_JUMP_SLOT:
2648 return reloc_class_plt;
2649 case R_X86_64_COPY:
2650 return reloc_class_copy;
2651 default:
2652 return reloc_class_normal;
2653 }
2654 }
2655
2656 /* Finish up the dynamic sections. */
2657
2658 static bfd_boolean
2659 elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
2660 {
2661 struct elf64_x86_64_link_hash_table *htab;
2662 bfd *dynobj;
2663 asection *sdyn;
2664
2665 htab = elf64_x86_64_hash_table (info);
2666 dynobj = htab->elf.dynobj;
2667 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2668
2669 if (htab->elf.dynamic_sections_created)
2670 {
2671 Elf64_External_Dyn *dyncon, *dynconend;
2672
2673 if (sdyn == NULL || htab->sgot == NULL)
2674 abort ();
2675
2676 dyncon = (Elf64_External_Dyn *) sdyn->contents;
2677 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->size);
2678 for (; dyncon < dynconend; dyncon++)
2679 {
2680 Elf_Internal_Dyn dyn;
2681 asection *s;
2682
2683 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
2684
2685 switch (dyn.d_tag)
2686 {
2687 default:
2688 continue;
2689
2690 case DT_PLTGOT:
2691 s = htab->sgotplt;
2692 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
2693 break;
2694
2695 case DT_JMPREL:
2696 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
2697 break;
2698
2699 case DT_PLTRELSZ:
2700 s = htab->srelplt->output_section;
2701 dyn.d_un.d_val = s->size;
2702 break;
2703
2704 case DT_RELASZ:
2705 /* The procedure linkage table relocs (DT_JMPREL) should
2706 not be included in the overall relocs (DT_RELA).
2707 Therefore, we override the DT_RELASZ entry here to
2708 make it not include the JMPREL relocs. Since the
2709 linker script arranges for .rela.plt to follow all
2710 other relocation sections, we don't have to worry
2711 about changing the DT_RELA entry. */
2712 if (htab->srelplt != NULL)
2713 {
2714 s = htab->srelplt->output_section;
2715 dyn.d_un.d_val -= s->size;
2716 }
2717 break;
2718 }
2719
2720 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
2721 }
2722
2723 /* Fill in the special first entry in the procedure linkage table. */
2724 if (htab->splt && htab->splt->size > 0)
2725 {
2726 /* Fill in the first entry in the procedure linkage table. */
2727 memcpy (htab->splt->contents, elf64_x86_64_plt0_entry,
2728 PLT_ENTRY_SIZE);
2729 /* Add offset for pushq GOT+8(%rip), since the instruction
2730 uses 6 bytes subtract this value. */
2731 bfd_put_32 (output_bfd,
2732 (htab->sgotplt->output_section->vma
2733 + htab->sgotplt->output_offset
2734 + 8
2735 - htab->splt->output_section->vma
2736 - htab->splt->output_offset
2737 - 6),
2738 htab->splt->contents + 2);
2739 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
2740 the end of the instruction. */
2741 bfd_put_32 (output_bfd,
2742 (htab->sgotplt->output_section->vma
2743 + htab->sgotplt->output_offset
2744 + 16
2745 - htab->splt->output_section->vma
2746 - htab->splt->output_offset
2747 - 12),
2748 htab->splt->contents + 8);
2749
2750 elf_section_data (htab->splt->output_section)->this_hdr.sh_entsize =
2751 PLT_ENTRY_SIZE;
2752 }
2753 }
2754
2755 if (htab->sgotplt)
2756 {
2757 /* Fill in the first three entries in the global offset table. */
2758 if (htab->sgotplt->size > 0)
2759 {
2760 /* Set the first entry in the global offset table to the address of
2761 the dynamic section. */
2762 if (sdyn == NULL)
2763 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents);
2764 else
2765 bfd_put_64 (output_bfd,
2766 sdyn->output_section->vma + sdyn->output_offset,
2767 htab->sgotplt->contents);
2768 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
2769 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE);
2770 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE*2);
2771 }
2772
2773 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize =
2774 GOT_ENTRY_SIZE;
2775 }
2776
2777 if (htab->sgot && htab->sgot->size > 0)
2778 elf_section_data (htab->sgot->output_section)->this_hdr.sh_entsize
2779 = GOT_ENTRY_SIZE;
2780
2781 return TRUE;
2782 }
2783
2784 /* Return address for Ith PLT stub in section PLT, for relocation REL
2785 or (bfd_vma) -1 if it should not be included. */
2786
2787 static bfd_vma
2788 elf64_x86_64_plt_sym_val (bfd_vma i, const asection *plt,
2789 const arelent *rel ATTRIBUTE_UNUSED)
2790 {
2791 return plt->vma + (i + 1) * PLT_ENTRY_SIZE;
2792 }
2793
2794 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
2795 #define TARGET_LITTLE_NAME "elf64-x86-64"
2796 #define ELF_ARCH bfd_arch_i386
2797 #define ELF_MACHINE_CODE EM_X86_64
2798 #define ELF_MAXPAGESIZE 0x100000
2799
2800 #define elf_backend_can_gc_sections 1
2801 #define elf_backend_can_refcount 1
2802 #define elf_backend_want_got_plt 1
2803 #define elf_backend_plt_readonly 1
2804 #define elf_backend_want_plt_sym 0
2805 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
2806 #define elf_backend_rela_normal 1
2807
2808 #define elf_info_to_howto elf64_x86_64_info_to_howto
2809
2810 #define bfd_elf64_bfd_link_hash_table_create \
2811 elf64_x86_64_link_hash_table_create
2812 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
2813
2814 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
2815 #define elf_backend_check_relocs elf64_x86_64_check_relocs
2816 #define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol
2817 #define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections
2818 #define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections
2819 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
2820 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
2821 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
2822 #define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus
2823 #define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo
2824 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
2825 #define elf_backend_relocate_section elf64_x86_64_relocate_section
2826 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
2827 #define elf_backend_plt_sym_val elf64_x86_64_plt_sym_val
2828 #define elf_backend_object_p elf64_x86_64_elf_object_p
2829 #define bfd_elf64_mkobject elf64_x86_64_mkobject
2830
2831 #include "elf64-target.h"
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