2005-06-20 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, 2005
3 Free Software Foundation, Inc.
4 Contributed by Jan Hubicka <jh@suse.cz>.
5
6 This file is part of BFD, the Binary File Descriptor library.
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
21
22 #include "bfd.h"
23 #include "sysdep.h"
24 #include "bfdlink.h"
25 #include "libbfd.h"
26 #include "elf-bfd.h"
27
28 #include "elf/x86-64.h"
29
30 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
31 #define MINUS_ONE (~ (bfd_vma) 0)
32
33 /* The relocation "howto" table. Order of fields:
34 type, size, bitsize, pc_relative, complain_on_overflow,
35 special_function, name, partial_inplace, src_mask, dst_pack, pcrel_offset. */
36 static reloc_howto_type x86_64_elf_howto_table[] =
37 {
38 HOWTO(R_X86_64_NONE, 0, 0, 0, FALSE, 0, complain_overflow_dont,
39 bfd_elf_generic_reloc, "R_X86_64_NONE", FALSE, 0x00000000, 0x00000000,
40 FALSE),
41 HOWTO(R_X86_64_64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
42 bfd_elf_generic_reloc, "R_X86_64_64", FALSE, MINUS_ONE, MINUS_ONE,
43 FALSE),
44 HOWTO(R_X86_64_PC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
45 bfd_elf_generic_reloc, "R_X86_64_PC32", FALSE, 0xffffffff, 0xffffffff,
46 TRUE),
47 HOWTO(R_X86_64_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
48 bfd_elf_generic_reloc, "R_X86_64_GOT32", FALSE, 0xffffffff, 0xffffffff,
49 FALSE),
50 HOWTO(R_X86_64_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
51 bfd_elf_generic_reloc, "R_X86_64_PLT32", FALSE, 0xffffffff, 0xffffffff,
52 TRUE),
53 HOWTO(R_X86_64_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
54 bfd_elf_generic_reloc, "R_X86_64_COPY", FALSE, 0xffffffff, 0xffffffff,
55 FALSE),
56 HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
57 bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", FALSE, MINUS_ONE,
58 MINUS_ONE, FALSE),
59 HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
60 bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", FALSE, MINUS_ONE,
61 MINUS_ONE, FALSE),
62 HOWTO(R_X86_64_RELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
63 bfd_elf_generic_reloc, "R_X86_64_RELATIVE", FALSE, MINUS_ONE,
64 MINUS_ONE, FALSE),
65 HOWTO(R_X86_64_GOTPCREL, 0, 2, 32, TRUE, 0, complain_overflow_signed,
66 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", FALSE, 0xffffffff,
67 0xffffffff, TRUE),
68 HOWTO(R_X86_64_32, 0, 2, 32, FALSE, 0, complain_overflow_unsigned,
69 bfd_elf_generic_reloc, "R_X86_64_32", FALSE, 0xffffffff, 0xffffffff,
70 FALSE),
71 HOWTO(R_X86_64_32S, 0, 2, 32, FALSE, 0, complain_overflow_signed,
72 bfd_elf_generic_reloc, "R_X86_64_32S", FALSE, 0xffffffff, 0xffffffff,
73 FALSE),
74 HOWTO(R_X86_64_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
75 bfd_elf_generic_reloc, "R_X86_64_16", FALSE, 0xffff, 0xffff, FALSE),
76 HOWTO(R_X86_64_PC16,0, 1, 16, TRUE, 0, complain_overflow_bitfield,
77 bfd_elf_generic_reloc, "R_X86_64_PC16", FALSE, 0xffff, 0xffff, TRUE),
78 HOWTO(R_X86_64_8, 0, 0, 8, FALSE, 0, complain_overflow_signed,
79 bfd_elf_generic_reloc, "R_X86_64_8", FALSE, 0xff, 0xff, FALSE),
80 HOWTO(R_X86_64_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed,
81 bfd_elf_generic_reloc, "R_X86_64_PC8", FALSE, 0xff, 0xff, TRUE),
82 HOWTO(R_X86_64_DTPMOD64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
83 bfd_elf_generic_reloc, "R_X86_64_DTPMOD64", FALSE, MINUS_ONE,
84 MINUS_ONE, FALSE),
85 HOWTO(R_X86_64_DTPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
86 bfd_elf_generic_reloc, "R_X86_64_DTPOFF64", FALSE, MINUS_ONE,
87 MINUS_ONE, FALSE),
88 HOWTO(R_X86_64_TPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
89 bfd_elf_generic_reloc, "R_X86_64_TPOFF64", FALSE, MINUS_ONE,
90 MINUS_ONE, FALSE),
91 HOWTO(R_X86_64_TLSGD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
92 bfd_elf_generic_reloc, "R_X86_64_TLSGD", FALSE, 0xffffffff,
93 0xffffffff, TRUE),
94 HOWTO(R_X86_64_TLSLD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
95 bfd_elf_generic_reloc, "R_X86_64_TLSLD", FALSE, 0xffffffff,
96 0xffffffff, TRUE),
97 HOWTO(R_X86_64_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
98 bfd_elf_generic_reloc, "R_X86_64_DTPOFF32", FALSE, 0xffffffff,
99 0xffffffff, FALSE),
100 HOWTO(R_X86_64_GOTTPOFF, 0, 2, 32, TRUE, 0, complain_overflow_signed,
101 bfd_elf_generic_reloc, "R_X86_64_GOTTPOFF", FALSE, 0xffffffff,
102 0xffffffff, TRUE),
103 HOWTO(R_X86_64_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
104 bfd_elf_generic_reloc, "R_X86_64_TPOFF32", FALSE, 0xffffffff,
105 0xffffffff, FALSE),
106 HOWTO(R_X86_64_PC64, 0, 4, 64, TRUE, 0, complain_overflow_bitfield,
107 bfd_elf_generic_reloc, "R_X86_64_PC64", FALSE, MINUS_ONE, MINUS_ONE,
108 TRUE),
109 HOWTO(R_X86_64_GOTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
110 bfd_elf_generic_reloc, "R_X86_64_GOTOFF64",
111 FALSE, MINUS_ONE, MINUS_ONE, FALSE),
112 HOWTO(R_X86_64_GOTPC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
113 bfd_elf_generic_reloc, "R_X86_64_GOTPC32",
114 FALSE, 0xffffffff, 0xffffffff, TRUE),
115
116 /* GNU extension to record C++ vtable hierarchy. */
117 HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, FALSE, 0, complain_overflow_dont,
118 NULL, "R_X86_64_GNU_VTINHERIT", FALSE, 0, 0, FALSE),
119
120 /* GNU extension to record C++ vtable member usage. */
121 HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, FALSE, 0, complain_overflow_dont,
122 _bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", FALSE, 0, 0,
123 FALSE)
124 };
125
126 /* Map BFD relocs to the x86_64 elf relocs. */
127 struct elf_reloc_map
128 {
129 bfd_reloc_code_real_type bfd_reloc_val;
130 unsigned char elf_reloc_val;
131 };
132
133 static const struct elf_reloc_map x86_64_reloc_map[] =
134 {
135 { BFD_RELOC_NONE, R_X86_64_NONE, },
136 { BFD_RELOC_64, R_X86_64_64, },
137 { BFD_RELOC_32_PCREL, R_X86_64_PC32, },
138 { BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,},
139 { BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,},
140 { BFD_RELOC_X86_64_COPY, R_X86_64_COPY, },
141 { BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, },
142 { BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, },
143 { BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, },
144 { BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, },
145 { BFD_RELOC_32, R_X86_64_32, },
146 { BFD_RELOC_X86_64_32S, R_X86_64_32S, },
147 { BFD_RELOC_16, R_X86_64_16, },
148 { BFD_RELOC_16_PCREL, R_X86_64_PC16, },
149 { BFD_RELOC_8, R_X86_64_8, },
150 { BFD_RELOC_8_PCREL, R_X86_64_PC8, },
151 { BFD_RELOC_X86_64_DTPMOD64, R_X86_64_DTPMOD64, },
152 { BFD_RELOC_X86_64_DTPOFF64, R_X86_64_DTPOFF64, },
153 { BFD_RELOC_X86_64_TPOFF64, R_X86_64_TPOFF64, },
154 { BFD_RELOC_X86_64_TLSGD, R_X86_64_TLSGD, },
155 { BFD_RELOC_X86_64_TLSLD, R_X86_64_TLSLD, },
156 { BFD_RELOC_X86_64_DTPOFF32, R_X86_64_DTPOFF32, },
157 { BFD_RELOC_X86_64_GOTTPOFF, R_X86_64_GOTTPOFF, },
158 { BFD_RELOC_X86_64_TPOFF32, R_X86_64_TPOFF32, },
159 { BFD_RELOC_64_PCREL, R_X86_64_PC64, },
160 { BFD_RELOC_X86_64_GOTOFF64, R_X86_64_GOTOFF64, },
161 { BFD_RELOC_X86_64_GOTPC32, R_X86_64_GOTPC32, },
162 { BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
163 { BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
164 };
165
166
167 /* Given a BFD reloc type, return a HOWTO structure. */
168 static reloc_howto_type *
169 elf64_x86_64_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
170 bfd_reloc_code_real_type code)
171 {
172 unsigned int i;
173
174 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
175 i++)
176 {
177 if (x86_64_reloc_map[i].bfd_reloc_val == code)
178 return &x86_64_elf_howto_table[i];
179 }
180 return 0;
181 }
182
183 /* Given an x86_64 ELF reloc type, fill in an arelent structure. */
184
185 static void
186 elf64_x86_64_info_to_howto (bfd *abfd ATTRIBUTE_UNUSED, arelent *cache_ptr,
187 Elf_Internal_Rela *dst)
188 {
189 unsigned r_type, i;
190
191 r_type = ELF64_R_TYPE (dst->r_info);
192 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT)
193 {
194 BFD_ASSERT (r_type <= (unsigned int) R_X86_64_GOTPC32);
195 i = r_type;
196 }
197 else
198 {
199 BFD_ASSERT (r_type < (unsigned int) R_X86_64_max);
200 i = r_type - ((unsigned int) R_X86_64_GNU_VTINHERIT - R_X86_64_GOTPC32 - 1);
201 }
202 cache_ptr->howto = &x86_64_elf_howto_table[i];
203 BFD_ASSERT (r_type == cache_ptr->howto->type);
204 }
205 \f
206 /* Support for core dump NOTE sections. */
207 static bfd_boolean
208 elf64_x86_64_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
209 {
210 int offset;
211 size_t size;
212
213 switch (note->descsz)
214 {
215 default:
216 return FALSE;
217
218 case 336: /* sizeof(istruct elf_prstatus) on Linux/x86_64 */
219 /* pr_cursig */
220 elf_tdata (abfd)->core_signal
221 = bfd_get_16 (abfd, note->descdata + 12);
222
223 /* pr_pid */
224 elf_tdata (abfd)->core_pid
225 = bfd_get_32 (abfd, note->descdata + 32);
226
227 /* pr_reg */
228 offset = 112;
229 size = 216;
230
231 break;
232 }
233
234 /* Make a ".reg/999" section. */
235 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
236 size, note->descpos + offset);
237 }
238
239 static bfd_boolean
240 elf64_x86_64_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
241 {
242 switch (note->descsz)
243 {
244 default:
245 return FALSE;
246
247 case 136: /* sizeof(struct elf_prpsinfo) on Linux/x86_64 */
248 elf_tdata (abfd)->core_program
249 = _bfd_elfcore_strndup (abfd, note->descdata + 40, 16);
250 elf_tdata (abfd)->core_command
251 = _bfd_elfcore_strndup (abfd, note->descdata + 56, 80);
252 }
253
254 /* Note that for some reason, a spurious space is tacked
255 onto the end of the args in some (at least one anyway)
256 implementations, so strip it off if it exists. */
257
258 {
259 char *command = elf_tdata (abfd)->core_command;
260 int n = strlen (command);
261
262 if (0 < n && command[n - 1] == ' ')
263 command[n - 1] = '\0';
264 }
265
266 return TRUE;
267 }
268 \f
269 /* Functions for the x86-64 ELF linker. */
270
271 /* The name of the dynamic interpreter. This is put in the .interp
272 section. */
273
274 #define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
275
276 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
277 copying dynamic variables from a shared lib into an app's dynbss
278 section, and instead use a dynamic relocation to point into the
279 shared lib. */
280 #define ELIMINATE_COPY_RELOCS 1
281
282 /* The size in bytes of an entry in the global offset table. */
283
284 #define GOT_ENTRY_SIZE 8
285
286 /* The size in bytes of an entry in the procedure linkage table. */
287
288 #define PLT_ENTRY_SIZE 16
289
290 /* The first entry in a procedure linkage table looks like this. See the
291 SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
292
293 static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
294 {
295 0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
296 0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
297 0x90, 0x90, 0x90, 0x90 /* pad out to 16 bytes with nops. */
298 };
299
300 /* Subsequent entries in a procedure linkage table look like this. */
301
302 static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
303 {
304 0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
305 0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
306 0x68, /* pushq immediate */
307 0, 0, 0, 0, /* replaced with index into relocation table. */
308 0xe9, /* jmp relative */
309 0, 0, 0, 0 /* replaced with offset to start of .plt0. */
310 };
311
312 /* The x86-64 linker needs to keep track of the number of relocs that
313 it decides to copy as dynamic relocs in check_relocs for each symbol.
314 This is so that it can later discard them if they are found to be
315 unnecessary. We store the information in a field extending the
316 regular ELF linker hash table. */
317
318 struct elf64_x86_64_dyn_relocs
319 {
320 /* Next section. */
321 struct elf64_x86_64_dyn_relocs *next;
322
323 /* The input section of the reloc. */
324 asection *sec;
325
326 /* Total number of relocs copied for the input section. */
327 bfd_size_type count;
328
329 /* Number of pc-relative relocs copied for the input section. */
330 bfd_size_type pc_count;
331 };
332
333 /* x86-64 ELF linker hash entry. */
334
335 struct elf64_x86_64_link_hash_entry
336 {
337 struct elf_link_hash_entry elf;
338
339 /* Track dynamic relocs copied for this symbol. */
340 struct elf64_x86_64_dyn_relocs *dyn_relocs;
341
342 #define GOT_UNKNOWN 0
343 #define GOT_NORMAL 1
344 #define GOT_TLS_GD 2
345 #define GOT_TLS_IE 3
346 unsigned char tls_type;
347 };
348
349 #define elf64_x86_64_hash_entry(ent) \
350 ((struct elf64_x86_64_link_hash_entry *)(ent))
351
352 struct elf64_x86_64_obj_tdata
353 {
354 struct elf_obj_tdata root;
355
356 /* tls_type for each local got entry. */
357 char *local_got_tls_type;
358 };
359
360 #define elf64_x86_64_tdata(abfd) \
361 ((struct elf64_x86_64_obj_tdata *) (abfd)->tdata.any)
362
363 #define elf64_x86_64_local_got_tls_type(abfd) \
364 (elf64_x86_64_tdata (abfd)->local_got_tls_type)
365
366
367 /* x86-64 ELF linker hash table. */
368
369 struct elf64_x86_64_link_hash_table
370 {
371 struct elf_link_hash_table elf;
372
373 /* Short-cuts to get to dynamic linker sections. */
374 asection *sgot;
375 asection *sgotplt;
376 asection *srelgot;
377 asection *splt;
378 asection *srelplt;
379 asection *sdynbss;
380 asection *srelbss;
381
382 union {
383 bfd_signed_vma refcount;
384 bfd_vma offset;
385 } tls_ld_got;
386
387 /* Small local sym to section mapping cache. */
388 struct sym_sec_cache sym_sec;
389 };
390
391 /* Get the x86-64 ELF linker hash table from a link_info structure. */
392
393 #define elf64_x86_64_hash_table(p) \
394 ((struct elf64_x86_64_link_hash_table *) ((p)->hash))
395
396 /* Create an entry in an x86-64 ELF linker hash table. */
397
398 static struct bfd_hash_entry *
399 link_hash_newfunc (struct bfd_hash_entry *entry, struct bfd_hash_table *table,
400 const char *string)
401 {
402 /* Allocate the structure if it has not already been allocated by a
403 subclass. */
404 if (entry == NULL)
405 {
406 entry = bfd_hash_allocate (table,
407 sizeof (struct elf64_x86_64_link_hash_entry));
408 if (entry == NULL)
409 return entry;
410 }
411
412 /* Call the allocation method of the superclass. */
413 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
414 if (entry != NULL)
415 {
416 struct elf64_x86_64_link_hash_entry *eh;
417
418 eh = (struct elf64_x86_64_link_hash_entry *) entry;
419 eh->dyn_relocs = NULL;
420 eh->tls_type = GOT_UNKNOWN;
421 }
422
423 return entry;
424 }
425
426 /* Create an X86-64 ELF linker hash table. */
427
428 static struct bfd_link_hash_table *
429 elf64_x86_64_link_hash_table_create (bfd *abfd)
430 {
431 struct elf64_x86_64_link_hash_table *ret;
432 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table);
433
434 ret = (struct elf64_x86_64_link_hash_table *) bfd_malloc (amt);
435 if (ret == NULL)
436 return NULL;
437
438 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc))
439 {
440 free (ret);
441 return NULL;
442 }
443
444 ret->sgot = NULL;
445 ret->sgotplt = NULL;
446 ret->srelgot = NULL;
447 ret->splt = NULL;
448 ret->srelplt = NULL;
449 ret->sdynbss = NULL;
450 ret->srelbss = NULL;
451 ret->sym_sec.abfd = NULL;
452 ret->tls_ld_got.refcount = 0;
453
454 return &ret->elf.root;
455 }
456
457 /* Create .got, .gotplt, and .rela.got sections in DYNOBJ, and set up
458 shortcuts to them in our hash table. */
459
460 static bfd_boolean
461 create_got_section (bfd *dynobj, struct bfd_link_info *info)
462 {
463 struct elf64_x86_64_link_hash_table *htab;
464
465 if (! _bfd_elf_create_got_section (dynobj, info))
466 return FALSE;
467
468 htab = elf64_x86_64_hash_table (info);
469 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
470 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
471 if (!htab->sgot || !htab->sgotplt)
472 abort ();
473
474 htab->srelgot = bfd_make_section_with_flags (dynobj, ".rela.got",
475 (SEC_ALLOC | SEC_LOAD
476 | SEC_HAS_CONTENTS
477 | SEC_IN_MEMORY
478 | SEC_LINKER_CREATED
479 | SEC_READONLY));
480 if (htab->srelgot == NULL
481 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 3))
482 return FALSE;
483 return TRUE;
484 }
485
486 /* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and
487 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our
488 hash table. */
489
490 static bfd_boolean
491 elf64_x86_64_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info)
492 {
493 struct elf64_x86_64_link_hash_table *htab;
494
495 htab = elf64_x86_64_hash_table (info);
496 if (!htab->sgot && !create_got_section (dynobj, info))
497 return FALSE;
498
499 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
500 return FALSE;
501
502 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
503 htab->srelplt = bfd_get_section_by_name (dynobj, ".rela.plt");
504 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
505 if (!info->shared)
506 htab->srelbss = bfd_get_section_by_name (dynobj, ".rela.bss");
507
508 if (!htab->splt || !htab->srelplt || !htab->sdynbss
509 || (!info->shared && !htab->srelbss))
510 abort ();
511
512 return TRUE;
513 }
514
515 /* Copy the extra info we tack onto an elf_link_hash_entry. */
516
517 static void
518 elf64_x86_64_copy_indirect_symbol (const struct elf_backend_data *bed,
519 struct elf_link_hash_entry *dir,
520 struct elf_link_hash_entry *ind)
521 {
522 struct elf64_x86_64_link_hash_entry *edir, *eind;
523
524 edir = (struct elf64_x86_64_link_hash_entry *) dir;
525 eind = (struct elf64_x86_64_link_hash_entry *) ind;
526
527 if (eind->dyn_relocs != NULL)
528 {
529 if (edir->dyn_relocs != NULL)
530 {
531 struct elf64_x86_64_dyn_relocs **pp;
532 struct elf64_x86_64_dyn_relocs *p;
533
534 if (ind->root.type == bfd_link_hash_indirect)
535 abort ();
536
537 /* Add reloc counts against the weak sym to the strong sym
538 list. Merge any entries against the same section. */
539 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
540 {
541 struct elf64_x86_64_dyn_relocs *q;
542
543 for (q = edir->dyn_relocs; q != NULL; q = q->next)
544 if (q->sec == p->sec)
545 {
546 q->pc_count += p->pc_count;
547 q->count += p->count;
548 *pp = p->next;
549 break;
550 }
551 if (q == NULL)
552 pp = &p->next;
553 }
554 *pp = edir->dyn_relocs;
555 }
556
557 edir->dyn_relocs = eind->dyn_relocs;
558 eind->dyn_relocs = NULL;
559 }
560
561 if (ind->root.type == bfd_link_hash_indirect
562 && dir->got.refcount <= 0)
563 {
564 edir->tls_type = eind->tls_type;
565 eind->tls_type = GOT_UNKNOWN;
566 }
567
568 if (ELIMINATE_COPY_RELOCS
569 && ind->root.type != bfd_link_hash_indirect
570 && dir->dynamic_adjusted)
571 {
572 /* If called to transfer flags for a weakdef during processing
573 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
574 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
575 dir->ref_dynamic |= ind->ref_dynamic;
576 dir->ref_regular |= ind->ref_regular;
577 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
578 dir->needs_plt |= ind->needs_plt;
579 dir->pointer_equality_needed |= ind->pointer_equality_needed;
580 }
581 else
582 _bfd_elf_link_hash_copy_indirect (bed, dir, ind);
583 }
584
585 static bfd_boolean
586 elf64_x86_64_mkobject (bfd *abfd)
587 {
588 bfd_size_type amt = sizeof (struct elf64_x86_64_obj_tdata);
589 abfd->tdata.any = bfd_zalloc (abfd, amt);
590 if (abfd->tdata.any == NULL)
591 return FALSE;
592 return TRUE;
593 }
594
595 static bfd_boolean
596 elf64_x86_64_elf_object_p (bfd *abfd)
597 {
598 /* Set the right machine number for an x86-64 elf64 file. */
599 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
600 return TRUE;
601 }
602
603 static int
604 elf64_x86_64_tls_transition (struct bfd_link_info *info, int r_type, int is_local)
605 {
606 if (info->shared)
607 return r_type;
608
609 switch (r_type)
610 {
611 case R_X86_64_TLSGD:
612 case R_X86_64_GOTTPOFF:
613 if (is_local)
614 return R_X86_64_TPOFF32;
615 return R_X86_64_GOTTPOFF;
616 case R_X86_64_TLSLD:
617 return R_X86_64_TPOFF32;
618 }
619
620 return r_type;
621 }
622
623 /* Look through the relocs for a section during the first phase, and
624 calculate needed space in the global offset table, procedure
625 linkage table, and dynamic reloc sections. */
626
627 static bfd_boolean
628 elf64_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info, asection *sec,
629 const Elf_Internal_Rela *relocs)
630 {
631 struct elf64_x86_64_link_hash_table *htab;
632 Elf_Internal_Shdr *symtab_hdr;
633 struct elf_link_hash_entry **sym_hashes;
634 const Elf_Internal_Rela *rel;
635 const Elf_Internal_Rela *rel_end;
636 asection *sreloc;
637
638 if (info->relocatable)
639 return TRUE;
640
641 htab = elf64_x86_64_hash_table (info);
642 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
643 sym_hashes = elf_sym_hashes (abfd);
644
645 sreloc = NULL;
646
647 rel_end = relocs + sec->reloc_count;
648 for (rel = relocs; rel < rel_end; rel++)
649 {
650 unsigned int r_type;
651 unsigned long r_symndx;
652 struct elf_link_hash_entry *h;
653
654 r_symndx = ELF64_R_SYM (rel->r_info);
655 r_type = ELF64_R_TYPE (rel->r_info);
656
657 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
658 {
659 (*_bfd_error_handler) (_("%B: bad symbol index: %d"),
660 abfd, r_symndx);
661 return FALSE;
662 }
663
664 if (r_symndx < symtab_hdr->sh_info)
665 h = NULL;
666 else
667 {
668 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
669 while (h->root.type == bfd_link_hash_indirect
670 || h->root.type == bfd_link_hash_warning)
671 h = (struct elf_link_hash_entry *) h->root.u.i.link;
672 }
673
674 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
675 switch (r_type)
676 {
677 case R_X86_64_TLSLD:
678 htab->tls_ld_got.refcount += 1;
679 goto create_got;
680
681 case R_X86_64_TPOFF32:
682 if (info->shared)
683 {
684 (*_bfd_error_handler)
685 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
686 abfd,
687 x86_64_elf_howto_table[r_type].name,
688 (h) ? h->root.root.string : "a local symbol");
689 bfd_set_error (bfd_error_bad_value);
690 return FALSE;
691 }
692 break;
693
694 case R_X86_64_GOTTPOFF:
695 if (info->shared)
696 info->flags |= DF_STATIC_TLS;
697 /* Fall through */
698
699 case R_X86_64_GOT32:
700 case R_X86_64_GOTPCREL:
701 case R_X86_64_TLSGD:
702 /* This symbol requires a global offset table entry. */
703 {
704 int tls_type, old_tls_type;
705
706 switch (r_type)
707 {
708 default: tls_type = GOT_NORMAL; break;
709 case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
710 case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
711 }
712
713 if (h != NULL)
714 {
715 h->got.refcount += 1;
716 old_tls_type = elf64_x86_64_hash_entry (h)->tls_type;
717 }
718 else
719 {
720 bfd_signed_vma *local_got_refcounts;
721
722 /* This is a global offset table entry for a local symbol. */
723 local_got_refcounts = elf_local_got_refcounts (abfd);
724 if (local_got_refcounts == NULL)
725 {
726 bfd_size_type size;
727
728 size = symtab_hdr->sh_info;
729 size *= sizeof (bfd_signed_vma) + sizeof (char);
730 local_got_refcounts = ((bfd_signed_vma *)
731 bfd_zalloc (abfd, size));
732 if (local_got_refcounts == NULL)
733 return FALSE;
734 elf_local_got_refcounts (abfd) = local_got_refcounts;
735 elf64_x86_64_local_got_tls_type (abfd)
736 = (char *) (local_got_refcounts + symtab_hdr->sh_info);
737 }
738 local_got_refcounts[r_symndx] += 1;
739 old_tls_type
740 = elf64_x86_64_local_got_tls_type (abfd) [r_symndx];
741 }
742
743 /* If a TLS symbol is accessed using IE at least once,
744 there is no point to use dynamic model for it. */
745 if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
746 && (old_tls_type != GOT_TLS_GD || tls_type != GOT_TLS_IE))
747 {
748 if (old_tls_type == GOT_TLS_IE && tls_type == GOT_TLS_GD)
749 tls_type = old_tls_type;
750 else
751 {
752 (*_bfd_error_handler)
753 (_("%B: %s' accessed both as normal and thread local symbol"),
754 abfd, h ? h->root.root.string : "<local>");
755 return FALSE;
756 }
757 }
758
759 if (old_tls_type != tls_type)
760 {
761 if (h != NULL)
762 elf64_x86_64_hash_entry (h)->tls_type = tls_type;
763 else
764 elf64_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
765 }
766 }
767 /* Fall through */
768
769 case R_X86_64_GOTOFF64:
770 case R_X86_64_GOTPC32:
771 create_got:
772 if (htab->sgot == NULL)
773 {
774 if (htab->elf.dynobj == NULL)
775 htab->elf.dynobj = abfd;
776 if (!create_got_section (htab->elf.dynobj, info))
777 return FALSE;
778 }
779 break;
780
781 case R_X86_64_PLT32:
782 /* This symbol requires a procedure linkage table entry. We
783 actually build the entry in adjust_dynamic_symbol,
784 because this might be a case of linking PIC code which is
785 never referenced by a dynamic object, in which case we
786 don't need to generate a procedure linkage table entry
787 after all. */
788
789 /* If this is a local symbol, we resolve it directly without
790 creating a procedure linkage table entry. */
791 if (h == NULL)
792 continue;
793
794 h->needs_plt = 1;
795 h->plt.refcount += 1;
796 break;
797
798 case R_X86_64_8:
799 case R_X86_64_16:
800 case R_X86_64_32:
801 case R_X86_64_32S:
802 /* Let's help debug shared library creation. These relocs
803 cannot be used in shared libs. Don't error out for
804 sections we don't care about, such as debug sections or
805 non-constant sections. */
806 if (info->shared
807 && (sec->flags & SEC_ALLOC) != 0
808 && (sec->flags & SEC_READONLY) != 0)
809 {
810 (*_bfd_error_handler)
811 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
812 abfd,
813 x86_64_elf_howto_table[r_type].name,
814 (h) ? h->root.root.string : "a local symbol");
815 bfd_set_error (bfd_error_bad_value);
816 return FALSE;
817 }
818 /* Fall through. */
819
820 case R_X86_64_PC8:
821 case R_X86_64_PC16:
822 case R_X86_64_PC32:
823 case R_X86_64_PC64:
824 case R_X86_64_64:
825 if (h != NULL && !info->shared)
826 {
827 /* If this reloc is in a read-only section, we might
828 need a copy reloc. We can't check reliably at this
829 stage whether the section is read-only, as input
830 sections have not yet been mapped to output sections.
831 Tentatively set the flag for now, and correct in
832 adjust_dynamic_symbol. */
833 h->non_got_ref = 1;
834
835 /* We may need a .plt entry if the function this reloc
836 refers to is in a shared lib. */
837 h->plt.refcount += 1;
838 if (r_type != R_X86_64_PC32 && r_type != R_X86_64_PC64)
839 h->pointer_equality_needed = 1;
840 }
841
842 /* If we are creating a shared library, and this is a reloc
843 against a global symbol, or a non PC relative reloc
844 against a local symbol, then we need to copy the reloc
845 into the shared library. However, if we are linking with
846 -Bsymbolic, we do not need to copy a reloc against a
847 global symbol which is defined in an object we are
848 including in the link (i.e., DEF_REGULAR is set). At
849 this point we have not seen all the input files, so it is
850 possible that DEF_REGULAR is not set now but will be set
851 later (it is never cleared). In case of a weak definition,
852 DEF_REGULAR may be cleared later by a strong definition in
853 a shared library. We account for that possibility below by
854 storing information in the relocs_copied field of the hash
855 table entry. A similar situation occurs when creating
856 shared libraries and symbol visibility changes render the
857 symbol local.
858
859 If on the other hand, we are creating an executable, we
860 may need to keep relocations for symbols satisfied by a
861 dynamic library if we manage to avoid copy relocs for the
862 symbol. */
863 if ((info->shared
864 && (sec->flags & SEC_ALLOC) != 0
865 && (((r_type != R_X86_64_PC8)
866 && (r_type != R_X86_64_PC16)
867 && (r_type != R_X86_64_PC32)
868 && (r_type != R_X86_64_PC64))
869 || (h != NULL
870 && (! info->symbolic
871 || h->root.type == bfd_link_hash_defweak
872 || !h->def_regular))))
873 || (ELIMINATE_COPY_RELOCS
874 && !info->shared
875 && (sec->flags & SEC_ALLOC) != 0
876 && h != NULL
877 && (h->root.type == bfd_link_hash_defweak
878 || !h->def_regular)))
879 {
880 struct elf64_x86_64_dyn_relocs *p;
881 struct elf64_x86_64_dyn_relocs **head;
882
883 /* We must copy these reloc types into the output file.
884 Create a reloc section in dynobj and make room for
885 this reloc. */
886 if (sreloc == NULL)
887 {
888 const char *name;
889 bfd *dynobj;
890
891 name = (bfd_elf_string_from_elf_section
892 (abfd,
893 elf_elfheader (abfd)->e_shstrndx,
894 elf_section_data (sec)->rel_hdr.sh_name));
895 if (name == NULL)
896 return FALSE;
897
898 if (strncmp (name, ".rela", 5) != 0
899 || strcmp (bfd_get_section_name (abfd, sec),
900 name + 5) != 0)
901 {
902 (*_bfd_error_handler)
903 (_("%B: bad relocation section name `%s\'"),
904 abfd, name);
905 }
906
907 if (htab->elf.dynobj == NULL)
908 htab->elf.dynobj = abfd;
909
910 dynobj = htab->elf.dynobj;
911
912 sreloc = bfd_get_section_by_name (dynobj, name);
913 if (sreloc == NULL)
914 {
915 flagword flags;
916
917 flags = (SEC_HAS_CONTENTS | SEC_READONLY
918 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
919 if ((sec->flags & SEC_ALLOC) != 0)
920 flags |= SEC_ALLOC | SEC_LOAD;
921 sreloc = bfd_make_section_with_flags (dynobj,
922 name,
923 flags);
924 if (sreloc == NULL
925 || ! bfd_set_section_alignment (dynobj, sreloc, 3))
926 return FALSE;
927 }
928 elf_section_data (sec)->sreloc = sreloc;
929 }
930
931 /* If this is a global symbol, we count the number of
932 relocations we need for this symbol. */
933 if (h != NULL)
934 {
935 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs;
936 }
937 else
938 {
939 /* Track dynamic relocs needed for local syms too.
940 We really need local syms available to do this
941 easily. Oh well. */
942
943 asection *s;
944 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
945 sec, r_symndx);
946 if (s == NULL)
947 return FALSE;
948
949 head = ((struct elf64_x86_64_dyn_relocs **)
950 &elf_section_data (s)->local_dynrel);
951 }
952
953 p = *head;
954 if (p == NULL || p->sec != sec)
955 {
956 bfd_size_type amt = sizeof *p;
957 p = ((struct elf64_x86_64_dyn_relocs *)
958 bfd_alloc (htab->elf.dynobj, amt));
959 if (p == NULL)
960 return FALSE;
961 p->next = *head;
962 *head = p;
963 p->sec = sec;
964 p->count = 0;
965 p->pc_count = 0;
966 }
967
968 p->count += 1;
969 if (r_type == R_X86_64_PC8
970 || r_type == R_X86_64_PC16
971 || r_type == R_X86_64_PC32
972 || r_type == R_X86_64_PC64)
973 p->pc_count += 1;
974 }
975 break;
976
977 /* This relocation describes the C++ object vtable hierarchy.
978 Reconstruct it for later use during GC. */
979 case R_X86_64_GNU_VTINHERIT:
980 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
981 return FALSE;
982 break;
983
984 /* This relocation describes which C++ vtable entries are actually
985 used. Record for later use during GC. */
986 case R_X86_64_GNU_VTENTRY:
987 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
988 return FALSE;
989 break;
990
991 default:
992 break;
993 }
994 }
995
996 return TRUE;
997 }
998
999 /* Return the section that should be marked against GC for a given
1000 relocation. */
1001
1002 static asection *
1003 elf64_x86_64_gc_mark_hook (asection *sec,
1004 struct bfd_link_info *info ATTRIBUTE_UNUSED,
1005 Elf_Internal_Rela *rel,
1006 struct elf_link_hash_entry *h,
1007 Elf_Internal_Sym *sym)
1008 {
1009 if (h != NULL)
1010 {
1011 switch (ELF64_R_TYPE (rel->r_info))
1012 {
1013 case R_X86_64_GNU_VTINHERIT:
1014 case R_X86_64_GNU_VTENTRY:
1015 break;
1016
1017 default:
1018 switch (h->root.type)
1019 {
1020 case bfd_link_hash_defined:
1021 case bfd_link_hash_defweak:
1022 return h->root.u.def.section;
1023
1024 case bfd_link_hash_common:
1025 return h->root.u.c.p->section;
1026
1027 default:
1028 break;
1029 }
1030 }
1031 }
1032 else
1033 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
1034
1035 return NULL;
1036 }
1037
1038 /* Update the got entry reference counts for the section being removed. */
1039
1040 static bfd_boolean
1041 elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
1042 asection *sec, const Elf_Internal_Rela *relocs)
1043 {
1044 Elf_Internal_Shdr *symtab_hdr;
1045 struct elf_link_hash_entry **sym_hashes;
1046 bfd_signed_vma *local_got_refcounts;
1047 const Elf_Internal_Rela *rel, *relend;
1048
1049 elf_section_data (sec)->local_dynrel = NULL;
1050
1051 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1052 sym_hashes = elf_sym_hashes (abfd);
1053 local_got_refcounts = elf_local_got_refcounts (abfd);
1054
1055 relend = relocs + sec->reloc_count;
1056 for (rel = relocs; rel < relend; rel++)
1057 {
1058 unsigned long r_symndx;
1059 unsigned int r_type;
1060 struct elf_link_hash_entry *h = NULL;
1061
1062 r_symndx = ELF64_R_SYM (rel->r_info);
1063 if (r_symndx >= symtab_hdr->sh_info)
1064 {
1065 struct elf64_x86_64_link_hash_entry *eh;
1066 struct elf64_x86_64_dyn_relocs **pp;
1067 struct elf64_x86_64_dyn_relocs *p;
1068
1069 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1070 while (h->root.type == bfd_link_hash_indirect
1071 || h->root.type == bfd_link_hash_warning)
1072 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1073 eh = (struct elf64_x86_64_link_hash_entry *) h;
1074
1075 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1076 if (p->sec == sec)
1077 {
1078 /* Everything must go for SEC. */
1079 *pp = p->next;
1080 break;
1081 }
1082 }
1083
1084 r_type = ELF64_R_TYPE (rel->r_info);
1085 r_type = elf64_x86_64_tls_transition (info, r_type, h != NULL);
1086 switch (r_type)
1087 {
1088 case R_X86_64_TLSLD:
1089 if (elf64_x86_64_hash_table (info)->tls_ld_got.refcount > 0)
1090 elf64_x86_64_hash_table (info)->tls_ld_got.refcount -= 1;
1091 break;
1092
1093 case R_X86_64_TLSGD:
1094 case R_X86_64_GOTTPOFF:
1095 case R_X86_64_GOT32:
1096 case R_X86_64_GOTPCREL:
1097 if (h != NULL)
1098 {
1099 if (h->got.refcount > 0)
1100 h->got.refcount -= 1;
1101 }
1102 else if (local_got_refcounts != NULL)
1103 {
1104 if (local_got_refcounts[r_symndx] > 0)
1105 local_got_refcounts[r_symndx] -= 1;
1106 }
1107 break;
1108
1109 case R_X86_64_8:
1110 case R_X86_64_16:
1111 case R_X86_64_32:
1112 case R_X86_64_64:
1113 case R_X86_64_32S:
1114 case R_X86_64_PC8:
1115 case R_X86_64_PC16:
1116 case R_X86_64_PC32:
1117 case R_X86_64_PC64:
1118 if (info->shared)
1119 break;
1120 /* Fall thru */
1121
1122 case R_X86_64_PLT32:
1123 if (h != NULL)
1124 {
1125 if (h->plt.refcount > 0)
1126 h->plt.refcount -= 1;
1127 }
1128 break;
1129
1130 default:
1131 break;
1132 }
1133 }
1134
1135 return TRUE;
1136 }
1137
1138 /* Adjust a symbol defined by a dynamic object and referenced by a
1139 regular object. The current definition is in some section of the
1140 dynamic object, but we're not including those sections. We have to
1141 change the definition to something the rest of the link can
1142 understand. */
1143
1144 static bfd_boolean
1145 elf64_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
1146 struct elf_link_hash_entry *h)
1147 {
1148 struct elf64_x86_64_link_hash_table *htab;
1149 asection *s;
1150 unsigned int power_of_two;
1151
1152 /* If this is a function, put it in the procedure linkage table. We
1153 will fill in the contents of the procedure linkage table later,
1154 when we know the address of the .got section. */
1155 if (h->type == STT_FUNC
1156 || h->needs_plt)
1157 {
1158 if (h->plt.refcount <= 0
1159 || SYMBOL_CALLS_LOCAL (info, h)
1160 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1161 && h->root.type == bfd_link_hash_undefweak))
1162 {
1163 /* This case can occur if we saw a PLT32 reloc in an input
1164 file, but the symbol was never referred to by a dynamic
1165 object, or if all references were garbage collected. In
1166 such a case, we don't actually need to build a procedure
1167 linkage table, and we can just do a PC32 reloc instead. */
1168 h->plt.offset = (bfd_vma) -1;
1169 h->needs_plt = 0;
1170 }
1171
1172 return TRUE;
1173 }
1174 else
1175 /* It's possible that we incorrectly decided a .plt reloc was
1176 needed for an R_X86_64_PC32 reloc to a non-function sym in
1177 check_relocs. We can't decide accurately between function and
1178 non-function syms in check-relocs; Objects loaded later in
1179 the link may change h->type. So fix it now. */
1180 h->plt.offset = (bfd_vma) -1;
1181
1182 /* If this is a weak symbol, and there is a real definition, the
1183 processor independent code will have arranged for us to see the
1184 real definition first, and we can just use the same value. */
1185 if (h->u.weakdef != NULL)
1186 {
1187 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1188 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1189 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1190 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1191 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1192 h->non_got_ref = h->u.weakdef->non_got_ref;
1193 return TRUE;
1194 }
1195
1196 /* This is a reference to a symbol defined by a dynamic object which
1197 is not a function. */
1198
1199 /* If we are creating a shared library, we must presume that the
1200 only references to the symbol are via the global offset table.
1201 For such cases we need not do anything here; the relocations will
1202 be handled correctly by relocate_section. */
1203 if (info->shared)
1204 return TRUE;
1205
1206 /* If there are no references to this symbol that do not use the
1207 GOT, we don't need to generate a copy reloc. */
1208 if (!h->non_got_ref)
1209 return TRUE;
1210
1211 /* If -z nocopyreloc was given, we won't generate them either. */
1212 if (info->nocopyreloc)
1213 {
1214 h->non_got_ref = 0;
1215 return TRUE;
1216 }
1217
1218 if (ELIMINATE_COPY_RELOCS)
1219 {
1220 struct elf64_x86_64_link_hash_entry * eh;
1221 struct elf64_x86_64_dyn_relocs *p;
1222
1223 eh = (struct elf64_x86_64_link_hash_entry *) h;
1224 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1225 {
1226 s = p->sec->output_section;
1227 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1228 break;
1229 }
1230
1231 /* If we didn't find any dynamic relocs in read-only sections, then
1232 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1233 if (p == NULL)
1234 {
1235 h->non_got_ref = 0;
1236 return TRUE;
1237 }
1238 }
1239
1240 /* We must allocate the symbol in our .dynbss section, which will
1241 become part of the .bss section of the executable. There will be
1242 an entry for this symbol in the .dynsym section. The dynamic
1243 object will contain position independent code, so all references
1244 from the dynamic object to this symbol will go through the global
1245 offset table. The dynamic linker will use the .dynsym entry to
1246 determine the address it must put in the global offset table, so
1247 both the dynamic object and the regular object will refer to the
1248 same memory location for the variable. */
1249
1250 htab = elf64_x86_64_hash_table (info);
1251
1252 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
1253 to copy the initial value out of the dynamic object and into the
1254 runtime process image. */
1255 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1256 {
1257 htab->srelbss->size += sizeof (Elf64_External_Rela);
1258 h->needs_copy = 1;
1259 }
1260
1261 /* We need to figure out the alignment required for this symbol. I
1262 have no idea how ELF linkers handle this. 16-bytes is the size
1263 of the largest type that requires hard alignment -- long double. */
1264 /* FIXME: This is VERY ugly. Should be fixed for all architectures using
1265 this construct. */
1266 power_of_two = bfd_log2 (h->size);
1267 if (power_of_two > 4)
1268 power_of_two = 4;
1269
1270 /* Apply the required alignment. */
1271 s = htab->sdynbss;
1272 s->size = BFD_ALIGN (s->size, (bfd_size_type) (1 << power_of_two));
1273 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1274 {
1275 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1276 return FALSE;
1277 }
1278
1279 /* Define the symbol as being at this point in the section. */
1280 h->root.u.def.section = s;
1281 h->root.u.def.value = s->size;
1282
1283 /* Increment the section size to make room for the symbol. */
1284 s->size += h->size;
1285
1286 return TRUE;
1287 }
1288
1289 /* Allocate space in .plt, .got and associated reloc sections for
1290 dynamic relocs. */
1291
1292 static bfd_boolean
1293 allocate_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1294 {
1295 struct bfd_link_info *info;
1296 struct elf64_x86_64_link_hash_table *htab;
1297 struct elf64_x86_64_link_hash_entry *eh;
1298 struct elf64_x86_64_dyn_relocs *p;
1299
1300 if (h->root.type == bfd_link_hash_indirect)
1301 return TRUE;
1302
1303 if (h->root.type == bfd_link_hash_warning)
1304 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1305
1306 info = (struct bfd_link_info *) inf;
1307 htab = elf64_x86_64_hash_table (info);
1308
1309 if (htab->elf.dynamic_sections_created
1310 && h->plt.refcount > 0)
1311 {
1312 /* Make sure this symbol is output as a dynamic symbol.
1313 Undefined weak syms won't yet be marked as dynamic. */
1314 if (h->dynindx == -1
1315 && !h->forced_local)
1316 {
1317 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1318 return FALSE;
1319 }
1320
1321 if (info->shared
1322 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
1323 {
1324 asection *s = htab->splt;
1325
1326 /* If this is the first .plt entry, make room for the special
1327 first entry. */
1328 if (s->size == 0)
1329 s->size += PLT_ENTRY_SIZE;
1330
1331 h->plt.offset = s->size;
1332
1333 /* If this symbol is not defined in a regular file, and we are
1334 not generating a shared library, then set the symbol to this
1335 location in the .plt. This is required to make function
1336 pointers compare as equal between the normal executable and
1337 the shared library. */
1338 if (! info->shared
1339 && !h->def_regular)
1340 {
1341 h->root.u.def.section = s;
1342 h->root.u.def.value = h->plt.offset;
1343 }
1344
1345 /* Make room for this entry. */
1346 s->size += PLT_ENTRY_SIZE;
1347
1348 /* We also need to make an entry in the .got.plt section, which
1349 will be placed in the .got section by the linker script. */
1350 htab->sgotplt->size += GOT_ENTRY_SIZE;
1351
1352 /* We also need to make an entry in the .rela.plt section. */
1353 htab->srelplt->size += sizeof (Elf64_External_Rela);
1354 }
1355 else
1356 {
1357 h->plt.offset = (bfd_vma) -1;
1358 h->needs_plt = 0;
1359 }
1360 }
1361 else
1362 {
1363 h->plt.offset = (bfd_vma) -1;
1364 h->needs_plt = 0;
1365 }
1366
1367 /* If R_X86_64_GOTTPOFF symbol is now local to the binary,
1368 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
1369 if (h->got.refcount > 0
1370 && !info->shared
1371 && h->dynindx == -1
1372 && elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
1373 h->got.offset = (bfd_vma) -1;
1374 else if (h->got.refcount > 0)
1375 {
1376 asection *s;
1377 bfd_boolean dyn;
1378 int tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1379
1380 /* Make sure this symbol is output as a dynamic symbol.
1381 Undefined weak syms won't yet be marked as dynamic. */
1382 if (h->dynindx == -1
1383 && !h->forced_local)
1384 {
1385 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1386 return FALSE;
1387 }
1388
1389 s = htab->sgot;
1390 h->got.offset = s->size;
1391 s->size += GOT_ENTRY_SIZE;
1392 /* R_X86_64_TLSGD needs 2 consecutive GOT slots. */
1393 if (tls_type == GOT_TLS_GD)
1394 s->size += GOT_ENTRY_SIZE;
1395 dyn = htab->elf.dynamic_sections_created;
1396 /* R_X86_64_TLSGD needs one dynamic relocation if local symbol
1397 and two if global.
1398 R_X86_64_GOTTPOFF needs one dynamic relocation. */
1399 if ((tls_type == GOT_TLS_GD && h->dynindx == -1)
1400 || tls_type == GOT_TLS_IE)
1401 htab->srelgot->size += sizeof (Elf64_External_Rela);
1402 else if (tls_type == GOT_TLS_GD)
1403 htab->srelgot->size += 2 * sizeof (Elf64_External_Rela);
1404 else if ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1405 || h->root.type != bfd_link_hash_undefweak)
1406 && (info->shared
1407 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
1408 htab->srelgot->size += sizeof (Elf64_External_Rela);
1409 }
1410 else
1411 h->got.offset = (bfd_vma) -1;
1412
1413 eh = (struct elf64_x86_64_link_hash_entry *) h;
1414 if (eh->dyn_relocs == NULL)
1415 return TRUE;
1416
1417 /* In the shared -Bsymbolic case, discard space allocated for
1418 dynamic pc-relative relocs against symbols which turn out to be
1419 defined in regular objects. For the normal shared case, discard
1420 space for pc-relative relocs that have become local due to symbol
1421 visibility changes. */
1422
1423 if (info->shared)
1424 {
1425 /* Relocs that use pc_count are those that appear on a call
1426 insn, or certain REL relocs that can generated via assembly.
1427 We want calls to protected symbols to resolve directly to the
1428 function rather than going via the plt. If people want
1429 function pointer comparisons to work as expected then they
1430 should avoid writing weird assembly. */
1431 if (SYMBOL_CALLS_LOCAL (info, h))
1432 {
1433 struct elf64_x86_64_dyn_relocs **pp;
1434
1435 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1436 {
1437 p->count -= p->pc_count;
1438 p->pc_count = 0;
1439 if (p->count == 0)
1440 *pp = p->next;
1441 else
1442 pp = &p->next;
1443 }
1444 }
1445
1446 /* Also discard relocs on undefined weak syms with non-default
1447 visibility. */
1448 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1449 && h->root.type == bfd_link_hash_undefweak)
1450 eh->dyn_relocs = NULL;
1451 }
1452 else if (ELIMINATE_COPY_RELOCS)
1453 {
1454 /* For the non-shared case, discard space for relocs against
1455 symbols which turn out to need copy relocs or are not
1456 dynamic. */
1457
1458 if (!h->non_got_ref
1459 && ((h->def_dynamic
1460 && !h->def_regular)
1461 || (htab->elf.dynamic_sections_created
1462 && (h->root.type == bfd_link_hash_undefweak
1463 || h->root.type == bfd_link_hash_undefined))))
1464 {
1465 /* Make sure this symbol is output as a dynamic symbol.
1466 Undefined weak syms won't yet be marked as dynamic. */
1467 if (h->dynindx == -1
1468 && !h->forced_local)
1469 {
1470 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1471 return FALSE;
1472 }
1473
1474 /* If that succeeded, we know we'll be keeping all the
1475 relocs. */
1476 if (h->dynindx != -1)
1477 goto keep;
1478 }
1479
1480 eh->dyn_relocs = NULL;
1481
1482 keep: ;
1483 }
1484
1485 /* Finally, allocate space. */
1486 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1487 {
1488 asection *sreloc = elf_section_data (p->sec)->sreloc;
1489 sreloc->size += p->count * sizeof (Elf64_External_Rela);
1490 }
1491
1492 return TRUE;
1493 }
1494
1495 /* Find any dynamic relocs that apply to read-only sections. */
1496
1497 static bfd_boolean
1498 readonly_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1499 {
1500 struct elf64_x86_64_link_hash_entry *eh;
1501 struct elf64_x86_64_dyn_relocs *p;
1502
1503 if (h->root.type == bfd_link_hash_warning)
1504 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1505
1506 eh = (struct elf64_x86_64_link_hash_entry *) h;
1507 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1508 {
1509 asection *s = p->sec->output_section;
1510
1511 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1512 {
1513 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1514
1515 info->flags |= DF_TEXTREL;
1516
1517 /* Not an error, just cut short the traversal. */
1518 return FALSE;
1519 }
1520 }
1521 return TRUE;
1522 }
1523
1524 /* Set the sizes of the dynamic sections. */
1525
1526 static bfd_boolean
1527 elf64_x86_64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
1528 struct bfd_link_info *info)
1529 {
1530 struct elf64_x86_64_link_hash_table *htab;
1531 bfd *dynobj;
1532 asection *s;
1533 bfd_boolean relocs;
1534 bfd *ibfd;
1535
1536 htab = elf64_x86_64_hash_table (info);
1537 dynobj = htab->elf.dynobj;
1538 if (dynobj == NULL)
1539 abort ();
1540
1541 if (htab->elf.dynamic_sections_created)
1542 {
1543 /* Set the contents of the .interp section to the interpreter. */
1544 if (info->executable)
1545 {
1546 s = bfd_get_section_by_name (dynobj, ".interp");
1547 if (s == NULL)
1548 abort ();
1549 s->size = sizeof ELF_DYNAMIC_INTERPRETER;
1550 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1551 }
1552 }
1553
1554 /* Set up .got offsets for local syms, and space for local dynamic
1555 relocs. */
1556 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1557 {
1558 bfd_signed_vma *local_got;
1559 bfd_signed_vma *end_local_got;
1560 char *local_tls_type;
1561 bfd_size_type locsymcount;
1562 Elf_Internal_Shdr *symtab_hdr;
1563 asection *srel;
1564
1565 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1566 continue;
1567
1568 for (s = ibfd->sections; s != NULL; s = s->next)
1569 {
1570 struct elf64_x86_64_dyn_relocs *p;
1571
1572 for (p = *((struct elf64_x86_64_dyn_relocs **)
1573 &elf_section_data (s)->local_dynrel);
1574 p != NULL;
1575 p = p->next)
1576 {
1577 if (!bfd_is_abs_section (p->sec)
1578 && bfd_is_abs_section (p->sec->output_section))
1579 {
1580 /* Input section has been discarded, either because
1581 it is a copy of a linkonce section or due to
1582 linker script /DISCARD/, so we'll be discarding
1583 the relocs too. */
1584 }
1585 else if (p->count != 0)
1586 {
1587 srel = elf_section_data (p->sec)->sreloc;
1588 srel->size += p->count * sizeof (Elf64_External_Rela);
1589 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1590 info->flags |= DF_TEXTREL;
1591
1592 }
1593 }
1594 }
1595
1596 local_got = elf_local_got_refcounts (ibfd);
1597 if (!local_got)
1598 continue;
1599
1600 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1601 locsymcount = symtab_hdr->sh_info;
1602 end_local_got = local_got + locsymcount;
1603 local_tls_type = elf64_x86_64_local_got_tls_type (ibfd);
1604 s = htab->sgot;
1605 srel = htab->srelgot;
1606 for (; local_got < end_local_got; ++local_got, ++local_tls_type)
1607 {
1608 if (*local_got > 0)
1609 {
1610 *local_got = s->size;
1611 s->size += GOT_ENTRY_SIZE;
1612 if (*local_tls_type == GOT_TLS_GD)
1613 s->size += GOT_ENTRY_SIZE;
1614 if (info->shared
1615 || *local_tls_type == GOT_TLS_GD
1616 || *local_tls_type == GOT_TLS_IE)
1617 srel->size += sizeof (Elf64_External_Rela);
1618 }
1619 else
1620 *local_got = (bfd_vma) -1;
1621 }
1622 }
1623
1624 if (htab->tls_ld_got.refcount > 0)
1625 {
1626 /* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD
1627 relocs. */
1628 htab->tls_ld_got.offset = htab->sgot->size;
1629 htab->sgot->size += 2 * GOT_ENTRY_SIZE;
1630 htab->srelgot->size += sizeof (Elf64_External_Rela);
1631 }
1632 else
1633 htab->tls_ld_got.offset = -1;
1634
1635 /* Allocate global sym .plt and .got entries, and space for global
1636 sym dynamic relocs. */
1637 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1638
1639 /* We now have determined the sizes of the various dynamic sections.
1640 Allocate memory for them. */
1641 relocs = FALSE;
1642 for (s = dynobj->sections; s != NULL; s = s->next)
1643 {
1644 if ((s->flags & SEC_LINKER_CREATED) == 0)
1645 continue;
1646
1647 if (s == htab->splt
1648 || s == htab->sgot
1649 || s == htab->sgotplt
1650 || s == htab->sdynbss)
1651 {
1652 /* Strip this section if we don't need it; see the
1653 comment below. */
1654 }
1655 else if (strncmp (bfd_get_section_name (dynobj, s), ".rela", 5) == 0)
1656 {
1657 if (s->size != 0 && s != htab->srelplt)
1658 relocs = TRUE;
1659
1660 /* We use the reloc_count field as a counter if we need
1661 to copy relocs into the output file. */
1662 s->reloc_count = 0;
1663 }
1664 else
1665 {
1666 /* It's not one of our sections, so don't allocate space. */
1667 continue;
1668 }
1669
1670 if (s->size == 0)
1671 {
1672 /* If we don't need this section, strip it from the
1673 output file. This is mostly to handle .rela.bss and
1674 .rela.plt. We must create both sections in
1675 create_dynamic_sections, because they must be created
1676 before the linker maps input sections to output
1677 sections. The linker does that before
1678 adjust_dynamic_symbol is called, and it is that
1679 function which decides whether anything needs to go
1680 into these sections. */
1681
1682 s->flags |= SEC_EXCLUDE;
1683 continue;
1684 }
1685
1686 /* Allocate memory for the section contents. We use bfd_zalloc
1687 here in case unused entries are not reclaimed before the
1688 section's contents are written out. This should not happen,
1689 but this way if it does, we get a R_X86_64_NONE reloc instead
1690 of garbage. */
1691 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->size);
1692 if (s->contents == NULL)
1693 return FALSE;
1694 }
1695
1696 if (htab->elf.dynamic_sections_created)
1697 {
1698 /* Add some entries to the .dynamic section. We fill in the
1699 values later, in elf64_x86_64_finish_dynamic_sections, but we
1700 must add the entries now so that we get the correct size for
1701 the .dynamic section. The DT_DEBUG entry is filled in by the
1702 dynamic linker and used by the debugger. */
1703 #define add_dynamic_entry(TAG, VAL) \
1704 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1705
1706 if (info->executable)
1707 {
1708 if (!add_dynamic_entry (DT_DEBUG, 0))
1709 return FALSE;
1710 }
1711
1712 if (htab->splt->size != 0)
1713 {
1714 if (!add_dynamic_entry (DT_PLTGOT, 0)
1715 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1716 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1717 || !add_dynamic_entry (DT_JMPREL, 0))
1718 return FALSE;
1719 }
1720
1721 if (relocs)
1722 {
1723 if (!add_dynamic_entry (DT_RELA, 0)
1724 || !add_dynamic_entry (DT_RELASZ, 0)
1725 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
1726 return FALSE;
1727
1728 /* If any dynamic relocs apply to a read-only section,
1729 then we need a DT_TEXTREL entry. */
1730 if ((info->flags & DF_TEXTREL) == 0)
1731 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
1732 (PTR) info);
1733
1734 if ((info->flags & DF_TEXTREL) != 0)
1735 {
1736 if (!add_dynamic_entry (DT_TEXTREL, 0))
1737 return FALSE;
1738 }
1739 }
1740 }
1741 #undef add_dynamic_entry
1742
1743 return TRUE;
1744 }
1745
1746 /* Return the base VMA address which should be subtracted from real addresses
1747 when resolving @dtpoff relocation.
1748 This is PT_TLS segment p_vaddr. */
1749
1750 static bfd_vma
1751 dtpoff_base (struct bfd_link_info *info)
1752 {
1753 /* If tls_sec is NULL, we should have signalled an error already. */
1754 if (elf_hash_table (info)->tls_sec == NULL)
1755 return 0;
1756 return elf_hash_table (info)->tls_sec->vma;
1757 }
1758
1759 /* Return the relocation value for @tpoff relocation
1760 if STT_TLS virtual address is ADDRESS. */
1761
1762 static bfd_vma
1763 tpoff (struct bfd_link_info *info, bfd_vma address)
1764 {
1765 struct elf_link_hash_table *htab = elf_hash_table (info);
1766
1767 /* If tls_segment is NULL, we should have signalled an error already. */
1768 if (htab->tls_sec == NULL)
1769 return 0;
1770 return address - htab->tls_size - htab->tls_sec->vma;
1771 }
1772
1773 /* Is the instruction before OFFSET in CONTENTS a 32bit relative
1774 branch? */
1775
1776 static bfd_boolean
1777 is_32bit_relative_branch (bfd_byte *contents, bfd_vma offset)
1778 {
1779 /* Opcode Instruction
1780 0xe8 call
1781 0xe9 jump
1782 0x0f 0x8x conditional jump */
1783 return ((offset > 0
1784 && (contents [offset - 1] == 0xe8
1785 || contents [offset - 1] == 0xe9))
1786 || (offset > 1
1787 && contents [offset - 2] == 0x0f
1788 && (contents [offset - 1] & 0xf0) == 0x80));
1789 }
1790
1791 /* Relocate an x86_64 ELF section. */
1792
1793 static bfd_boolean
1794 elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
1795 bfd *input_bfd, asection *input_section,
1796 bfd_byte *contents, Elf_Internal_Rela *relocs,
1797 Elf_Internal_Sym *local_syms,
1798 asection **local_sections)
1799 {
1800 struct elf64_x86_64_link_hash_table *htab;
1801 Elf_Internal_Shdr *symtab_hdr;
1802 struct elf_link_hash_entry **sym_hashes;
1803 bfd_vma *local_got_offsets;
1804 Elf_Internal_Rela *rel;
1805 Elf_Internal_Rela *relend;
1806
1807 if (info->relocatable)
1808 return TRUE;
1809
1810 htab = elf64_x86_64_hash_table (info);
1811 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1812 sym_hashes = elf_sym_hashes (input_bfd);
1813 local_got_offsets = elf_local_got_offsets (input_bfd);
1814
1815 rel = relocs;
1816 relend = relocs + input_section->reloc_count;
1817 for (; rel < relend; rel++)
1818 {
1819 unsigned int r_type;
1820 reloc_howto_type *howto;
1821 unsigned long r_symndx;
1822 struct elf_link_hash_entry *h;
1823 Elf_Internal_Sym *sym;
1824 asection *sec;
1825 bfd_vma off;
1826 bfd_vma relocation;
1827 bfd_boolean unresolved_reloc;
1828 bfd_reloc_status_type r;
1829 int tls_type;
1830
1831 r_type = ELF64_R_TYPE (rel->r_info);
1832 if (r_type == (int) R_X86_64_GNU_VTINHERIT
1833 || r_type == (int) R_X86_64_GNU_VTENTRY)
1834 continue;
1835
1836 if (r_type >= R_X86_64_max)
1837 {
1838 bfd_set_error (bfd_error_bad_value);
1839 return FALSE;
1840 }
1841
1842 howto = x86_64_elf_howto_table + r_type;
1843 r_symndx = ELF64_R_SYM (rel->r_info);
1844 h = NULL;
1845 sym = NULL;
1846 sec = NULL;
1847 unresolved_reloc = FALSE;
1848 if (r_symndx < symtab_hdr->sh_info)
1849 {
1850 sym = local_syms + r_symndx;
1851 sec = local_sections[r_symndx];
1852
1853 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
1854 }
1855 else
1856 {
1857 bfd_boolean warned;
1858
1859 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
1860 r_symndx, symtab_hdr, sym_hashes,
1861 h, sec, relocation,
1862 unresolved_reloc, warned);
1863 }
1864 /* When generating a shared object, the relocations handled here are
1865 copied into the output file to be resolved at run time. */
1866 switch (r_type)
1867 {
1868 case R_X86_64_GOT32:
1869 /* Relocation is to the entry for this symbol in the global
1870 offset table. */
1871 case R_X86_64_GOTPCREL:
1872 /* Use global offset table as symbol value. */
1873 if (htab->sgot == NULL)
1874 abort ();
1875
1876 if (h != NULL)
1877 {
1878 bfd_boolean dyn;
1879
1880 off = h->got.offset;
1881 dyn = htab->elf.dynamic_sections_created;
1882
1883 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
1884 || (info->shared
1885 && SYMBOL_REFERENCES_LOCAL (info, h))
1886 || (ELF_ST_VISIBILITY (h->other)
1887 && h->root.type == bfd_link_hash_undefweak))
1888 {
1889 /* This is actually a static link, or it is a -Bsymbolic
1890 link and the symbol is defined locally, or the symbol
1891 was forced to be local because of a version file. We
1892 must initialize this entry in the global offset table.
1893 Since the offset must always be a multiple of 8, we
1894 use the least significant bit to record whether we
1895 have initialized it already.
1896
1897 When doing a dynamic link, we create a .rela.got
1898 relocation entry to initialize the value. This is
1899 done in the finish_dynamic_symbol routine. */
1900 if ((off & 1) != 0)
1901 off &= ~1;
1902 else
1903 {
1904 bfd_put_64 (output_bfd, relocation,
1905 htab->sgot->contents + off);
1906 h->got.offset |= 1;
1907 }
1908 }
1909 else
1910 unresolved_reloc = FALSE;
1911 }
1912 else
1913 {
1914 if (local_got_offsets == NULL)
1915 abort ();
1916
1917 off = local_got_offsets[r_symndx];
1918
1919 /* The offset must always be a multiple of 8. We use
1920 the least significant bit to record whether we have
1921 already generated the necessary reloc. */
1922 if ((off & 1) != 0)
1923 off &= ~1;
1924 else
1925 {
1926 bfd_put_64 (output_bfd, relocation,
1927 htab->sgot->contents + off);
1928
1929 if (info->shared)
1930 {
1931 asection *s;
1932 Elf_Internal_Rela outrel;
1933 bfd_byte *loc;
1934
1935 /* We need to generate a R_X86_64_RELATIVE reloc
1936 for the dynamic linker. */
1937 s = htab->srelgot;
1938 if (s == NULL)
1939 abort ();
1940
1941 outrel.r_offset = (htab->sgot->output_section->vma
1942 + htab->sgot->output_offset
1943 + off);
1944 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
1945 outrel.r_addend = relocation;
1946 loc = s->contents;
1947 loc += s->reloc_count++ * sizeof (Elf64_External_Rela);
1948 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
1949 }
1950
1951 local_got_offsets[r_symndx] |= 1;
1952 }
1953 }
1954
1955 if (off >= (bfd_vma) -2)
1956 abort ();
1957
1958 relocation = htab->sgot->output_section->vma
1959 + htab->sgot->output_offset + off;
1960 if (r_type != R_X86_64_GOTPCREL)
1961 relocation -= htab->sgotplt->output_section->vma
1962 - htab->sgotplt->output_offset;
1963
1964 break;
1965
1966 case R_X86_64_GOTOFF64:
1967 /* Relocation is relative to the start of the global offset
1968 table. */
1969
1970 /* Check to make sure it isn't a protected function symbol
1971 for shared library since it may not be local when used
1972 as function address. */
1973 if (info->shared
1974 && h
1975 && h->def_regular
1976 && h->type == STT_FUNC
1977 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
1978 {
1979 (*_bfd_error_handler)
1980 (_("%B: relocation R_X86_64_GOTOFF64 against protected function `%s' can not be used when making a shared object"),
1981 input_bfd, h->root.root.string);
1982 bfd_set_error (bfd_error_bad_value);
1983 return FALSE;
1984 }
1985
1986 /* Note that sgot is not involved in this
1987 calculation. We always want the start of .got.plt. If we
1988 defined _GLOBAL_OFFSET_TABLE_ in a different way, as is
1989 permitted by the ABI, we might have to change this
1990 calculation. */
1991 relocation -= htab->sgotplt->output_section->vma
1992 + htab->sgotplt->output_offset;
1993 break;
1994
1995 case R_X86_64_GOTPC32:
1996 /* Use global offset table as symbol value. */
1997 relocation = htab->sgotplt->output_section->vma
1998 + htab->sgotplt->output_offset;
1999 unresolved_reloc = FALSE;
2000 break;
2001
2002 case R_X86_64_PLT32:
2003 /* Relocation is to the entry for this symbol in the
2004 procedure linkage table. */
2005
2006 /* Resolve a PLT32 reloc against a local symbol directly,
2007 without using the procedure linkage table. */
2008 if (h == NULL)
2009 break;
2010
2011 if (h->plt.offset == (bfd_vma) -1
2012 || htab->splt == NULL)
2013 {
2014 /* We didn't make a PLT entry for this symbol. This
2015 happens when statically linking PIC code, or when
2016 using -Bsymbolic. */
2017 break;
2018 }
2019
2020 relocation = (htab->splt->output_section->vma
2021 + htab->splt->output_offset
2022 + h->plt.offset);
2023 unresolved_reloc = FALSE;
2024 break;
2025
2026 case R_X86_64_PC8:
2027 case R_X86_64_PC16:
2028 case R_X86_64_PC32:
2029 if (info->shared
2030 && !SYMBOL_REFERENCES_LOCAL (info, h)
2031 && (input_section->flags & SEC_ALLOC) != 0
2032 && (input_section->flags & SEC_READONLY) != 0
2033 && (!h->def_regular
2034 || r_type != R_X86_64_PC32
2035 || h->type != STT_FUNC
2036 || ELF_ST_VISIBILITY (h->other) != STV_PROTECTED
2037 || !is_32bit_relative_branch (contents,
2038 rel->r_offset)))
2039 {
2040 if (h->def_regular
2041 && r_type == R_X86_64_PC32
2042 && h->type == STT_FUNC
2043 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
2044 (*_bfd_error_handler)
2045 (_("%B: relocation R_X86_64_PC32 against protected function `%s' can not be used when making a shared object"),
2046 input_bfd, h->root.root.string);
2047 else
2048 (*_bfd_error_handler)
2049 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
2050 input_bfd, x86_64_elf_howto_table[r_type].name,
2051 h->root.root.string);
2052 bfd_set_error (bfd_error_bad_value);
2053 return FALSE;
2054 }
2055 /* Fall through. */
2056
2057 case R_X86_64_8:
2058 case R_X86_64_16:
2059 case R_X86_64_32:
2060 case R_X86_64_PC64:
2061 case R_X86_64_64:
2062 /* FIXME: The ABI says the linker should make sure the value is
2063 the same when it's zeroextended to 64 bit. */
2064
2065 /* r_symndx will be zero only for relocs against symbols
2066 from removed linkonce sections, or sections discarded by
2067 a linker script. */
2068 if (r_symndx == 0
2069 || (input_section->flags & SEC_ALLOC) == 0)
2070 break;
2071
2072 if ((info->shared
2073 && (h == NULL
2074 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
2075 || h->root.type != bfd_link_hash_undefweak)
2076 && ((r_type != R_X86_64_PC8
2077 && r_type != R_X86_64_PC16
2078 && r_type != R_X86_64_PC32
2079 && r_type != R_X86_64_PC64)
2080 || !SYMBOL_CALLS_LOCAL (info, h)))
2081 || (ELIMINATE_COPY_RELOCS
2082 && !info->shared
2083 && h != NULL
2084 && h->dynindx != -1
2085 && !h->non_got_ref
2086 && ((h->def_dynamic
2087 && !h->def_regular)
2088 || h->root.type == bfd_link_hash_undefweak
2089 || h->root.type == bfd_link_hash_undefined)))
2090 {
2091 Elf_Internal_Rela outrel;
2092 bfd_byte *loc;
2093 bfd_boolean skip, relocate;
2094 asection *sreloc;
2095
2096 /* When generating a shared object, these relocations
2097 are copied into the output file to be resolved at run
2098 time. */
2099 skip = FALSE;
2100 relocate = FALSE;
2101
2102 outrel.r_offset =
2103 _bfd_elf_section_offset (output_bfd, info, input_section,
2104 rel->r_offset);
2105 if (outrel.r_offset == (bfd_vma) -1)
2106 skip = TRUE;
2107 else if (outrel.r_offset == (bfd_vma) -2)
2108 skip = TRUE, relocate = TRUE;
2109
2110 outrel.r_offset += (input_section->output_section->vma
2111 + input_section->output_offset);
2112
2113 if (skip)
2114 memset (&outrel, 0, sizeof outrel);
2115
2116 /* h->dynindx may be -1 if this symbol was marked to
2117 become local. */
2118 else if (h != NULL
2119 && h->dynindx != -1
2120 && (r_type == R_X86_64_PC8
2121 || r_type == R_X86_64_PC16
2122 || r_type == R_X86_64_PC32
2123 || r_type == R_X86_64_PC64
2124 || !info->shared
2125 || !info->symbolic
2126 || !h->def_regular))
2127 {
2128 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
2129 outrel.r_addend = rel->r_addend;
2130 }
2131 else
2132 {
2133 /* This symbol is local, or marked to become local. */
2134 if (r_type == R_X86_64_64)
2135 {
2136 relocate = TRUE;
2137 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2138 outrel.r_addend = relocation + rel->r_addend;
2139 }
2140 else
2141 {
2142 long sindx;
2143
2144 if (bfd_is_abs_section (sec))
2145 sindx = 0;
2146 else if (sec == NULL || sec->owner == NULL)
2147 {
2148 bfd_set_error (bfd_error_bad_value);
2149 return FALSE;
2150 }
2151 else
2152 {
2153 asection *osec;
2154
2155 osec = sec->output_section;
2156 sindx = elf_section_data (osec)->dynindx;
2157 BFD_ASSERT (sindx > 0);
2158 }
2159
2160 outrel.r_info = ELF64_R_INFO (sindx, r_type);
2161 outrel.r_addend = relocation + rel->r_addend;
2162 }
2163 }
2164
2165 sreloc = elf_section_data (input_section)->sreloc;
2166 if (sreloc == NULL)
2167 abort ();
2168
2169 loc = sreloc->contents;
2170 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
2171 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2172
2173 /* If this reloc is against an external symbol, we do
2174 not want to fiddle with the addend. Otherwise, we
2175 need to include the symbol value so that it becomes
2176 an addend for the dynamic reloc. */
2177 if (! relocate)
2178 continue;
2179 }
2180
2181 break;
2182
2183 case R_X86_64_TLSGD:
2184 case R_X86_64_GOTTPOFF:
2185 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
2186 tls_type = GOT_UNKNOWN;
2187 if (h == NULL && local_got_offsets)
2188 tls_type = elf64_x86_64_local_got_tls_type (input_bfd) [r_symndx];
2189 else if (h != NULL)
2190 {
2191 tls_type = elf64_x86_64_hash_entry (h)->tls_type;
2192 if (!info->shared && h->dynindx == -1 && tls_type == GOT_TLS_IE)
2193 r_type = R_X86_64_TPOFF32;
2194 }
2195 if (r_type == R_X86_64_TLSGD)
2196 {
2197 if (tls_type == GOT_TLS_IE)
2198 r_type = R_X86_64_GOTTPOFF;
2199 }
2200
2201 if (r_type == R_X86_64_TPOFF32)
2202 {
2203 BFD_ASSERT (! unresolved_reloc);
2204 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
2205 {
2206 unsigned int i;
2207 static unsigned char tlsgd[8]
2208 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2209
2210 /* GD->LE transition.
2211 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2212 .word 0x6666; rex64; call __tls_get_addr@plt
2213 Change it into:
2214 movq %fs:0, %rax
2215 leaq foo@tpoff(%rax), %rax */
2216 BFD_ASSERT (rel->r_offset >= 4);
2217 for (i = 0; i < 4; i++)
2218 BFD_ASSERT (bfd_get_8 (input_bfd,
2219 contents + rel->r_offset - 4 + i)
2220 == tlsgd[i]);
2221 BFD_ASSERT (rel->r_offset + 12 <= input_section->size);
2222 for (i = 0; i < 4; i++)
2223 BFD_ASSERT (bfd_get_8 (input_bfd,
2224 contents + rel->r_offset + 4 + i)
2225 == tlsgd[i+4]);
2226 BFD_ASSERT (rel + 1 < relend);
2227 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2228 memcpy (contents + rel->r_offset - 4,
2229 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0",
2230 16);
2231 bfd_put_32 (output_bfd, tpoff (info, relocation),
2232 contents + rel->r_offset + 8);
2233 /* Skip R_X86_64_PLT32. */
2234 rel++;
2235 continue;
2236 }
2237 else
2238 {
2239 unsigned int val, type, reg;
2240
2241 /* IE->LE transition:
2242 Originally it can be one of:
2243 movq foo@gottpoff(%rip), %reg
2244 addq foo@gottpoff(%rip), %reg
2245 We change it into:
2246 movq $foo, %reg
2247 leaq foo(%reg), %reg
2248 addq $foo, %reg. */
2249 BFD_ASSERT (rel->r_offset >= 3);
2250 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 3);
2251 BFD_ASSERT (val == 0x48 || val == 0x4c);
2252 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2253 BFD_ASSERT (type == 0x8b || type == 0x03);
2254 reg = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2255 BFD_ASSERT ((reg & 0xc7) == 5);
2256 reg >>= 3;
2257 BFD_ASSERT (rel->r_offset + 4 <= input_section->size);
2258 if (type == 0x8b)
2259 {
2260 /* movq */
2261 if (val == 0x4c)
2262 bfd_put_8 (output_bfd, 0x49,
2263 contents + rel->r_offset - 3);
2264 bfd_put_8 (output_bfd, 0xc7,
2265 contents + rel->r_offset - 2);
2266 bfd_put_8 (output_bfd, 0xc0 | reg,
2267 contents + rel->r_offset - 1);
2268 }
2269 else if (reg == 4)
2270 {
2271 /* addq -> addq - addressing with %rsp/%r12 is
2272 special */
2273 if (val == 0x4c)
2274 bfd_put_8 (output_bfd, 0x49,
2275 contents + rel->r_offset - 3);
2276 bfd_put_8 (output_bfd, 0x81,
2277 contents + rel->r_offset - 2);
2278 bfd_put_8 (output_bfd, 0xc0 | reg,
2279 contents + rel->r_offset - 1);
2280 }
2281 else
2282 {
2283 /* addq -> leaq */
2284 if (val == 0x4c)
2285 bfd_put_8 (output_bfd, 0x4d,
2286 contents + rel->r_offset - 3);
2287 bfd_put_8 (output_bfd, 0x8d,
2288 contents + rel->r_offset - 2);
2289 bfd_put_8 (output_bfd, 0x80 | reg | (reg << 3),
2290 contents + rel->r_offset - 1);
2291 }
2292 bfd_put_32 (output_bfd, tpoff (info, relocation),
2293 contents + rel->r_offset);
2294 continue;
2295 }
2296 }
2297
2298 if (htab->sgot == NULL)
2299 abort ();
2300
2301 if (h != NULL)
2302 off = h->got.offset;
2303 else
2304 {
2305 if (local_got_offsets == NULL)
2306 abort ();
2307
2308 off = local_got_offsets[r_symndx];
2309 }
2310
2311 if ((off & 1) != 0)
2312 off &= ~1;
2313 else
2314 {
2315 Elf_Internal_Rela outrel;
2316 bfd_byte *loc;
2317 int dr_type, indx;
2318
2319 if (htab->srelgot == NULL)
2320 abort ();
2321
2322 outrel.r_offset = (htab->sgot->output_section->vma
2323 + htab->sgot->output_offset + off);
2324
2325 indx = h && h->dynindx != -1 ? h->dynindx : 0;
2326 if (r_type == R_X86_64_TLSGD)
2327 dr_type = R_X86_64_DTPMOD64;
2328 else
2329 dr_type = R_X86_64_TPOFF64;
2330
2331 bfd_put_64 (output_bfd, 0, htab->sgot->contents + off);
2332 outrel.r_addend = 0;
2333 if (dr_type == R_X86_64_TPOFF64 && indx == 0)
2334 outrel.r_addend = relocation - dtpoff_base (info);
2335 outrel.r_info = ELF64_R_INFO (indx, dr_type);
2336
2337 loc = htab->srelgot->contents;
2338 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2339 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2340
2341 if (r_type == R_X86_64_TLSGD)
2342 {
2343 if (indx == 0)
2344 {
2345 BFD_ASSERT (! unresolved_reloc);
2346 bfd_put_64 (output_bfd,
2347 relocation - dtpoff_base (info),
2348 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2349 }
2350 else
2351 {
2352 bfd_put_64 (output_bfd, 0,
2353 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2354 outrel.r_info = ELF64_R_INFO (indx,
2355 R_X86_64_DTPOFF64);
2356 outrel.r_offset += GOT_ENTRY_SIZE;
2357 htab->srelgot->reloc_count++;
2358 loc += sizeof (Elf64_External_Rela);
2359 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2360 }
2361 }
2362
2363 if (h != NULL)
2364 h->got.offset |= 1;
2365 else
2366 local_got_offsets[r_symndx] |= 1;
2367 }
2368
2369 if (off >= (bfd_vma) -2)
2370 abort ();
2371 if (r_type == ELF64_R_TYPE (rel->r_info))
2372 {
2373 relocation = htab->sgot->output_section->vma
2374 + htab->sgot->output_offset + off;
2375 unresolved_reloc = FALSE;
2376 }
2377 else
2378 {
2379 unsigned int i;
2380 static unsigned char tlsgd[8]
2381 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2382
2383 /* GD->IE transition.
2384 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2385 .word 0x6666; rex64; call __tls_get_addr@plt
2386 Change it into:
2387 movq %fs:0, %rax
2388 addq foo@gottpoff(%rip), %rax */
2389 BFD_ASSERT (rel->r_offset >= 4);
2390 for (i = 0; i < 4; i++)
2391 BFD_ASSERT (bfd_get_8 (input_bfd,
2392 contents + rel->r_offset - 4 + i)
2393 == tlsgd[i]);
2394 BFD_ASSERT (rel->r_offset + 12 <= input_section->size);
2395 for (i = 0; i < 4; i++)
2396 BFD_ASSERT (bfd_get_8 (input_bfd,
2397 contents + rel->r_offset + 4 + i)
2398 == tlsgd[i+4]);
2399 BFD_ASSERT (rel + 1 < relend);
2400 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2401 memcpy (contents + rel->r_offset - 4,
2402 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0",
2403 16);
2404
2405 relocation = (htab->sgot->output_section->vma
2406 + htab->sgot->output_offset + off
2407 - rel->r_offset
2408 - input_section->output_section->vma
2409 - input_section->output_offset
2410 - 12);
2411 bfd_put_32 (output_bfd, relocation,
2412 contents + rel->r_offset + 8);
2413 /* Skip R_X86_64_PLT32. */
2414 rel++;
2415 continue;
2416 }
2417 break;
2418
2419 case R_X86_64_TLSLD:
2420 if (! info->shared)
2421 {
2422 /* LD->LE transition:
2423 Ensure it is:
2424 leaq foo@tlsld(%rip), %rdi; call __tls_get_addr@plt.
2425 We change it into:
2426 .word 0x6666; .byte 0x66; movl %fs:0, %rax. */
2427 BFD_ASSERT (rel->r_offset >= 3);
2428 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 3)
2429 == 0x48);
2430 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 2)
2431 == 0x8d);
2432 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 1)
2433 == 0x3d);
2434 BFD_ASSERT (rel->r_offset + 9 <= input_section->size);
2435 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2436 == 0xe8);
2437 BFD_ASSERT (rel + 1 < relend);
2438 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2439 memcpy (contents + rel->r_offset - 3,
2440 "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0", 12);
2441 /* Skip R_X86_64_PLT32. */
2442 rel++;
2443 continue;
2444 }
2445
2446 if (htab->sgot == NULL)
2447 abort ();
2448
2449 off = htab->tls_ld_got.offset;
2450 if (off & 1)
2451 off &= ~1;
2452 else
2453 {
2454 Elf_Internal_Rela outrel;
2455 bfd_byte *loc;
2456
2457 if (htab->srelgot == NULL)
2458 abort ();
2459
2460 outrel.r_offset = (htab->sgot->output_section->vma
2461 + htab->sgot->output_offset + off);
2462
2463 bfd_put_64 (output_bfd, 0,
2464 htab->sgot->contents + off);
2465 bfd_put_64 (output_bfd, 0,
2466 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2467 outrel.r_info = ELF64_R_INFO (0, R_X86_64_DTPMOD64);
2468 outrel.r_addend = 0;
2469 loc = htab->srelgot->contents;
2470 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2471 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2472 htab->tls_ld_got.offset |= 1;
2473 }
2474 relocation = htab->sgot->output_section->vma
2475 + htab->sgot->output_offset + off;
2476 unresolved_reloc = FALSE;
2477 break;
2478
2479 case R_X86_64_DTPOFF32:
2480 if (info->shared || (input_section->flags & SEC_CODE) == 0)
2481 relocation -= dtpoff_base (info);
2482 else
2483 relocation = tpoff (info, relocation);
2484 break;
2485
2486 case R_X86_64_TPOFF32:
2487 BFD_ASSERT (! info->shared);
2488 relocation = tpoff (info, relocation);
2489 break;
2490
2491 default:
2492 break;
2493 }
2494
2495 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
2496 because such sections are not SEC_ALLOC and thus ld.so will
2497 not process them. */
2498 if (unresolved_reloc
2499 && !((input_section->flags & SEC_DEBUGGING) != 0
2500 && h->def_dynamic))
2501 (*_bfd_error_handler)
2502 (_("%B(%A+0x%lx): unresolvable relocation against symbol `%s'"),
2503 input_bfd,
2504 input_section,
2505 (long) rel->r_offset,
2506 h->root.root.string);
2507
2508 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
2509 contents, rel->r_offset,
2510 relocation, rel->r_addend);
2511
2512 if (r != bfd_reloc_ok)
2513 {
2514 const char *name;
2515
2516 if (h != NULL)
2517 name = h->root.root.string;
2518 else
2519 {
2520 name = bfd_elf_string_from_elf_section (input_bfd,
2521 symtab_hdr->sh_link,
2522 sym->st_name);
2523 if (name == NULL)
2524 return FALSE;
2525 if (*name == '\0')
2526 name = bfd_section_name (input_bfd, sec);
2527 }
2528
2529 if (r == bfd_reloc_overflow)
2530 {
2531 if (h != NULL
2532 && h->root.type == bfd_link_hash_undefweak
2533 && howto->pc_relative)
2534 /* Ignore reloc overflow on branches to undefweak syms. */
2535 continue;
2536
2537 if (! ((*info->callbacks->reloc_overflow)
2538 (info, (h ? &h->root : NULL), name, howto->name,
2539 (bfd_vma) 0, input_bfd, input_section,
2540 rel->r_offset)))
2541 return FALSE;
2542 }
2543 else
2544 {
2545 (*_bfd_error_handler)
2546 (_("%B(%A+0x%lx): reloc against `%s': error %d"),
2547 input_bfd, input_section,
2548 (long) rel->r_offset, name, (int) r);
2549 return FALSE;
2550 }
2551 }
2552 }
2553
2554 return TRUE;
2555 }
2556
2557 /* Finish up dynamic symbol handling. We set the contents of various
2558 dynamic sections here. */
2559
2560 static bfd_boolean
2561 elf64_x86_64_finish_dynamic_symbol (bfd *output_bfd,
2562 struct bfd_link_info *info,
2563 struct elf_link_hash_entry *h,
2564 Elf_Internal_Sym *sym)
2565 {
2566 struct elf64_x86_64_link_hash_table *htab;
2567
2568 htab = elf64_x86_64_hash_table (info);
2569
2570 if (h->plt.offset != (bfd_vma) -1)
2571 {
2572 bfd_vma plt_index;
2573 bfd_vma got_offset;
2574 Elf_Internal_Rela rela;
2575 bfd_byte *loc;
2576
2577 /* This symbol has an entry in the procedure linkage table. Set
2578 it up. */
2579 if (h->dynindx == -1
2580 || htab->splt == NULL
2581 || htab->sgotplt == NULL
2582 || htab->srelplt == NULL)
2583 abort ();
2584
2585 /* Get the index in the procedure linkage table which
2586 corresponds to this symbol. This is the index of this symbol
2587 in all the symbols for which we are making plt entries. The
2588 first entry in the procedure linkage table is reserved. */
2589 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2590
2591 /* Get the offset into the .got table of the entry that
2592 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
2593 bytes. The first three are reserved for the dynamic linker. */
2594 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
2595
2596 /* Fill in the entry in the procedure linkage table. */
2597 memcpy (htab->splt->contents + h->plt.offset, elf64_x86_64_plt_entry,
2598 PLT_ENTRY_SIZE);
2599
2600 /* Insert the relocation positions of the plt section. The magic
2601 numbers at the end of the statements are the positions of the
2602 relocations in the plt section. */
2603 /* Put offset for jmp *name@GOTPCREL(%rip), since the
2604 instruction uses 6 bytes, subtract this value. */
2605 bfd_put_32 (output_bfd,
2606 (htab->sgotplt->output_section->vma
2607 + htab->sgotplt->output_offset
2608 + got_offset
2609 - htab->splt->output_section->vma
2610 - htab->splt->output_offset
2611 - h->plt.offset
2612 - 6),
2613 htab->splt->contents + h->plt.offset + 2);
2614 /* Put relocation index. */
2615 bfd_put_32 (output_bfd, plt_index,
2616 htab->splt->contents + h->plt.offset + 7);
2617 /* Put offset for jmp .PLT0. */
2618 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
2619 htab->splt->contents + h->plt.offset + 12);
2620
2621 /* Fill in the entry in the global offset table, initially this
2622 points to the pushq instruction in the PLT which is at offset 6. */
2623 bfd_put_64 (output_bfd, (htab->splt->output_section->vma
2624 + htab->splt->output_offset
2625 + h->plt.offset + 6),
2626 htab->sgotplt->contents + got_offset);
2627
2628 /* Fill in the entry in the .rela.plt section. */
2629 rela.r_offset = (htab->sgotplt->output_section->vma
2630 + htab->sgotplt->output_offset
2631 + got_offset);
2632 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
2633 rela.r_addend = 0;
2634 loc = htab->srelplt->contents + plt_index * sizeof (Elf64_External_Rela);
2635 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2636
2637 if (!h->def_regular)
2638 {
2639 /* Mark the symbol as undefined, rather than as defined in
2640 the .plt section. Leave the value if there were any
2641 relocations where pointer equality matters (this is a clue
2642 for the dynamic linker, to make function pointer
2643 comparisons work between an application and shared
2644 library), otherwise set it to zero. If a function is only
2645 called from a binary, there is no need to slow down
2646 shared libraries because of that. */
2647 sym->st_shndx = SHN_UNDEF;
2648 if (!h->pointer_equality_needed)
2649 sym->st_value = 0;
2650 }
2651 }
2652
2653 if (h->got.offset != (bfd_vma) -1
2654 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_GD
2655 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE)
2656 {
2657 Elf_Internal_Rela rela;
2658 bfd_byte *loc;
2659
2660 /* This symbol has an entry in the global offset table. Set it
2661 up. */
2662 if (htab->sgot == NULL || htab->srelgot == NULL)
2663 abort ();
2664
2665 rela.r_offset = (htab->sgot->output_section->vma
2666 + htab->sgot->output_offset
2667 + (h->got.offset &~ (bfd_vma) 1));
2668
2669 /* If this is a static link, or it is a -Bsymbolic link and the
2670 symbol is defined locally or was forced to be local because
2671 of a version file, we just want to emit a RELATIVE reloc.
2672 The entry in the global offset table will already have been
2673 initialized in the relocate_section function. */
2674 if (info->shared
2675 && SYMBOL_REFERENCES_LOCAL (info, h))
2676 {
2677 BFD_ASSERT((h->got.offset & 1) != 0);
2678 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2679 rela.r_addend = (h->root.u.def.value
2680 + h->root.u.def.section->output_section->vma
2681 + h->root.u.def.section->output_offset);
2682 }
2683 else
2684 {
2685 BFD_ASSERT((h->got.offset & 1) == 0);
2686 bfd_put_64 (output_bfd, (bfd_vma) 0,
2687 htab->sgot->contents + h->got.offset);
2688 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
2689 rela.r_addend = 0;
2690 }
2691
2692 loc = htab->srelgot->contents;
2693 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2694 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2695 }
2696
2697 if (h->needs_copy)
2698 {
2699 Elf_Internal_Rela rela;
2700 bfd_byte *loc;
2701
2702 /* This symbol needs a copy reloc. Set it up. */
2703
2704 if (h->dynindx == -1
2705 || (h->root.type != bfd_link_hash_defined
2706 && h->root.type != bfd_link_hash_defweak)
2707 || htab->srelbss == NULL)
2708 abort ();
2709
2710 rela.r_offset = (h->root.u.def.value
2711 + h->root.u.def.section->output_section->vma
2712 + h->root.u.def.section->output_offset);
2713 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
2714 rela.r_addend = 0;
2715 loc = htab->srelbss->contents;
2716 loc += htab->srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
2717 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2718 }
2719
2720 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
2721 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
2722 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
2723 sym->st_shndx = SHN_ABS;
2724
2725 return TRUE;
2726 }
2727
2728 /* Used to decide how to sort relocs in an optimal manner for the
2729 dynamic linker, before writing them out. */
2730
2731 static enum elf_reloc_type_class
2732 elf64_x86_64_reloc_type_class (const Elf_Internal_Rela *rela)
2733 {
2734 switch ((int) ELF64_R_TYPE (rela->r_info))
2735 {
2736 case R_X86_64_RELATIVE:
2737 return reloc_class_relative;
2738 case R_X86_64_JUMP_SLOT:
2739 return reloc_class_plt;
2740 case R_X86_64_COPY:
2741 return reloc_class_copy;
2742 default:
2743 return reloc_class_normal;
2744 }
2745 }
2746
2747 /* Finish up the dynamic sections. */
2748
2749 static bfd_boolean
2750 elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
2751 {
2752 struct elf64_x86_64_link_hash_table *htab;
2753 bfd *dynobj;
2754 asection *sdyn;
2755
2756 htab = elf64_x86_64_hash_table (info);
2757 dynobj = htab->elf.dynobj;
2758 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2759
2760 if (htab->elf.dynamic_sections_created)
2761 {
2762 Elf64_External_Dyn *dyncon, *dynconend;
2763
2764 if (sdyn == NULL || htab->sgot == NULL)
2765 abort ();
2766
2767 dyncon = (Elf64_External_Dyn *) sdyn->contents;
2768 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->size);
2769 for (; dyncon < dynconend; dyncon++)
2770 {
2771 Elf_Internal_Dyn dyn;
2772 asection *s;
2773
2774 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
2775
2776 switch (dyn.d_tag)
2777 {
2778 default:
2779 continue;
2780
2781 case DT_PLTGOT:
2782 s = htab->sgotplt;
2783 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
2784 break;
2785
2786 case DT_JMPREL:
2787 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
2788 break;
2789
2790 case DT_PLTRELSZ:
2791 s = htab->srelplt->output_section;
2792 dyn.d_un.d_val = s->size;
2793 break;
2794
2795 case DT_RELASZ:
2796 /* The procedure linkage table relocs (DT_JMPREL) should
2797 not be included in the overall relocs (DT_RELA).
2798 Therefore, we override the DT_RELASZ entry here to
2799 make it not include the JMPREL relocs. Since the
2800 linker script arranges for .rela.plt to follow all
2801 other relocation sections, we don't have to worry
2802 about changing the DT_RELA entry. */
2803 if (htab->srelplt != NULL)
2804 {
2805 s = htab->srelplt->output_section;
2806 dyn.d_un.d_val -= s->size;
2807 }
2808 break;
2809 }
2810
2811 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
2812 }
2813
2814 /* Fill in the special first entry in the procedure linkage table. */
2815 if (htab->splt && htab->splt->size > 0)
2816 {
2817 /* Fill in the first entry in the procedure linkage table. */
2818 memcpy (htab->splt->contents, elf64_x86_64_plt0_entry,
2819 PLT_ENTRY_SIZE);
2820 /* Add offset for pushq GOT+8(%rip), since the instruction
2821 uses 6 bytes subtract this value. */
2822 bfd_put_32 (output_bfd,
2823 (htab->sgotplt->output_section->vma
2824 + htab->sgotplt->output_offset
2825 + 8
2826 - htab->splt->output_section->vma
2827 - htab->splt->output_offset
2828 - 6),
2829 htab->splt->contents + 2);
2830 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
2831 the end of the instruction. */
2832 bfd_put_32 (output_bfd,
2833 (htab->sgotplt->output_section->vma
2834 + htab->sgotplt->output_offset
2835 + 16
2836 - htab->splt->output_section->vma
2837 - htab->splt->output_offset
2838 - 12),
2839 htab->splt->contents + 8);
2840
2841 elf_section_data (htab->splt->output_section)->this_hdr.sh_entsize =
2842 PLT_ENTRY_SIZE;
2843 }
2844 }
2845
2846 if (htab->sgotplt)
2847 {
2848 /* Fill in the first three entries in the global offset table. */
2849 if (htab->sgotplt->size > 0)
2850 {
2851 /* Set the first entry in the global offset table to the address of
2852 the dynamic section. */
2853 if (sdyn == NULL)
2854 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents);
2855 else
2856 bfd_put_64 (output_bfd,
2857 sdyn->output_section->vma + sdyn->output_offset,
2858 htab->sgotplt->contents);
2859 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
2860 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE);
2861 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE*2);
2862 }
2863
2864 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize =
2865 GOT_ENTRY_SIZE;
2866 }
2867
2868 if (htab->sgot && htab->sgot->size > 0)
2869 elf_section_data (htab->sgot->output_section)->this_hdr.sh_entsize
2870 = GOT_ENTRY_SIZE;
2871
2872 return TRUE;
2873 }
2874
2875 /* Return address for Ith PLT stub in section PLT, for relocation REL
2876 or (bfd_vma) -1 if it should not be included. */
2877
2878 static bfd_vma
2879 elf64_x86_64_plt_sym_val (bfd_vma i, const asection *plt,
2880 const arelent *rel ATTRIBUTE_UNUSED)
2881 {
2882 return plt->vma + (i + 1) * PLT_ENTRY_SIZE;
2883 }
2884
2885 /* Handle an x86-64 specific section when reading an object file. This
2886 is called when elfcode.h finds a section with an unknown type. */
2887
2888 static bfd_boolean
2889 elf64_x86_64_section_from_shdr (bfd *abfd,
2890 Elf_Internal_Shdr *hdr,
2891 const char *name,
2892 int shindex)
2893 {
2894 if (hdr->sh_type != SHT_X86_64_UNWIND)
2895 return FALSE;
2896
2897 if (! _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex))
2898 return FALSE;
2899
2900 return TRUE;
2901 }
2902
2903 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
2904 #define TARGET_LITTLE_NAME "elf64-x86-64"
2905 #define ELF_ARCH bfd_arch_i386
2906 #define ELF_MACHINE_CODE EM_X86_64
2907 #define ELF_MAXPAGESIZE 0x100000
2908
2909 #define elf_backend_can_gc_sections 1
2910 #define elf_backend_can_refcount 1
2911 #define elf_backend_want_got_plt 1
2912 #define elf_backend_plt_readonly 1
2913 #define elf_backend_want_plt_sym 0
2914 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
2915 #define elf_backend_rela_normal 1
2916
2917 #define elf_info_to_howto elf64_x86_64_info_to_howto
2918
2919 #define bfd_elf64_bfd_link_hash_table_create \
2920 elf64_x86_64_link_hash_table_create
2921 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
2922
2923 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
2924 #define elf_backend_check_relocs elf64_x86_64_check_relocs
2925 #define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol
2926 #define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections
2927 #define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections
2928 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
2929 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
2930 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
2931 #define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus
2932 #define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo
2933 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
2934 #define elf_backend_relocate_section elf64_x86_64_relocate_section
2935 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
2936 #define elf_backend_plt_sym_val elf64_x86_64_plt_sym_val
2937 #define elf_backend_object_p elf64_x86_64_elf_object_p
2938 #define bfd_elf64_mkobject elf64_x86_64_mkobject
2939
2940 #define elf_backend_section_from_shdr \
2941 elf64_x86_64_section_from_shdr
2942
2943 #include "elf64-target.h"
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