Merge from gcc:
[binutils.git] / bfd / elf64-x86-64.c
blob09a072b5b8eaf9aba974839d12464e0375b69466
1 /* X86-64 specific support for 64-bit ELF
2 Copyright 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
3 Contributed by Jan Hubicka <jh@suse.cz>.
5 This file is part of BFD, the Binary File Descriptor library.
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.
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.
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. */
21 #include "bfd.h"
22 #include "sysdep.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #include "elf-bfd.h"
27 #include "elf/x86-64.h"
29 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
30 #define MINUS_ONE (~ (bfd_vma) 0)
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[] =
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),
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),
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)
116 /* Map BFD relocs to the x86_64 elf relocs. */
117 struct elf_reloc_map
119 bfd_reloc_code_real_type bfd_reloc_val;
120 unsigned char elf_reloc_val;
123 static const struct elf_reloc_map x86_64_reloc_map[] =
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, },
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)
159 unsigned int i;
161 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
162 i++)
164 if (x86_64_reloc_map[i].bfd_reloc_val == code)
165 return &x86_64_elf_howto_table[i];
167 return 0;
170 /* Given an x86_64 ELF reloc type, fill in an arelent structure. */
172 static void
173 elf64_x86_64_info_to_howto (bfd *abfd ATTRIBUTE_UNUSED, arelent *cache_ptr,
174 Elf_Internal_Rela *dst)
176 unsigned r_type, i;
178 r_type = ELF64_R_TYPE (dst->r_info);
179 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT)
181 BFD_ASSERT (r_type <= (unsigned int) R_X86_64_TPOFF32);
182 i = r_type;
184 else
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);
189 cache_ptr->howto = &x86_64_elf_howto_table[i];
190 BFD_ASSERT (r_type == cache_ptr->howto->type);
193 /* Support for core dump NOTE sections. */
194 static bfd_boolean
195 elf64_x86_64_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
197 int offset;
198 size_t raw_size;
200 switch (note->descsz)
202 default:
203 return FALSE;
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);
210 /* pr_pid */
211 elf_tdata (abfd)->core_pid
212 = bfd_get_32 (abfd, note->descdata + 32);
214 /* pr_reg */
215 offset = 112;
216 raw_size = 216;
218 break;
221 /* Make a ".reg/999" section. */
222 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
223 raw_size, note->descpos + offset);
226 static bfd_boolean
227 elf64_x86_64_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
229 switch (note->descsz)
231 default:
232 return FALSE;
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);
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. */
246 char *command = elf_tdata (abfd)->core_command;
247 int n = strlen (command);
249 if (0 < n && command[n - 1] == ' ')
250 command[n - 1] = '\0';
253 return TRUE;
256 /* Functions for the x86-64 ELF linker. */
258 /* The name of the dynamic interpreter. This is put in the .interp
259 section. */
261 #define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
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
269 /* The size in bytes of an entry in the global offset table. */
271 #define GOT_ENTRY_SIZE 8
273 /* The size in bytes of an entry in the procedure linkage table. */
275 #define PLT_ENTRY_SIZE 16
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. */
280 static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
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. */
287 /* Subsequent entries in a procedure linkage table look like this. */
289 static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
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. */
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. */
305 struct elf64_x86_64_dyn_relocs
307 /* Next section. */
308 struct elf64_x86_64_dyn_relocs *next;
310 /* The input section of the reloc. */
311 asection *sec;
313 /* Total number of relocs copied for the input section. */
314 bfd_size_type count;
316 /* Number of pc-relative relocs copied for the input section. */
317 bfd_size_type pc_count;
320 /* x86-64 ELF linker hash entry. */
322 struct elf64_x86_64_link_hash_entry
324 struct elf_link_hash_entry elf;
326 /* Track dynamic relocs copied for this symbol. */
327 struct elf64_x86_64_dyn_relocs *dyn_relocs;
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;
336 #define elf64_x86_64_hash_entry(ent) \
337 ((struct elf64_x86_64_link_hash_entry *)(ent))
339 struct elf64_x86_64_obj_tdata
341 struct elf_obj_tdata root;
343 /* tls_type for each local got entry. */
344 char *local_got_tls_type;
347 #define elf64_x86_64_tdata(abfd) \
348 ((struct elf64_x86_64_obj_tdata *) (abfd)->tdata.any)
350 #define elf64_x86_64_local_got_tls_type(abfd) \
351 (elf64_x86_64_tdata (abfd)->local_got_tls_type)
354 /* x86-64 ELF linker hash table. */
356 struct elf64_x86_64_link_hash_table
358 struct elf_link_hash_table elf;
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;
369 union {
370 bfd_signed_vma refcount;
371 bfd_vma offset;
372 } tls_ld_got;
374 /* Small local sym to section mapping cache. */
375 struct sym_sec_cache sym_sec;
378 /* Get the x86-64 ELF linker hash table from a link_info structure. */
380 #define elf64_x86_64_hash_table(p) \
381 ((struct elf64_x86_64_link_hash_table *) ((p)->hash))
383 /* Create an entry in an x86-64 ELF linker hash table. */
385 static struct bfd_hash_entry *
386 link_hash_newfunc (struct bfd_hash_entry *entry, struct bfd_hash_table *table,
387 const char *string)
389 /* Allocate the structure if it has not already been allocated by a
390 subclass. */
391 if (entry == NULL)
393 entry = bfd_hash_allocate (table,
394 sizeof (struct elf64_x86_64_link_hash_entry));
395 if (entry == NULL)
396 return entry;
399 /* Call the allocation method of the superclass. */
400 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
401 if (entry != NULL)
403 struct elf64_x86_64_link_hash_entry *eh;
405 eh = (struct elf64_x86_64_link_hash_entry *) entry;
406 eh->dyn_relocs = NULL;
407 eh->tls_type = GOT_UNKNOWN;
410 return entry;
413 /* Create an X86-64 ELF linker hash table. */
415 static struct bfd_link_hash_table *
416 elf64_x86_64_link_hash_table_create (bfd *abfd)
418 struct elf64_x86_64_link_hash_table *ret;
419 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table);
421 ret = (struct elf64_x86_64_link_hash_table *) bfd_malloc (amt);
422 if (ret == NULL)
423 return NULL;
425 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc))
427 free (ret);
428 return NULL;
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;
441 return &ret->elf.root;
444 /* Create .got, .gotplt, and .rela.got sections in DYNOBJ, and set up
445 shortcuts to them in our hash table. */
447 static bfd_boolean
448 create_got_section (bfd *dynobj, struct bfd_link_info *info)
450 struct elf64_x86_64_link_hash_table *htab;
452 if (! _bfd_elf_create_got_section (dynobj, info))
453 return FALSE;
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 ();
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;
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. */
476 static bfd_boolean
477 elf64_x86_64_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info)
479 struct elf64_x86_64_link_hash_table *htab;
481 htab = elf64_x86_64_hash_table (info);
482 if (!htab->sgot && !create_got_section (dynobj, info))
483 return FALSE;
485 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
486 return FALSE;
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");
494 if (!htab->splt || !htab->srelplt || !htab->sdynbss
495 || (!info->shared && !htab->srelbss))
496 abort ();
498 return TRUE;
501 /* Copy the extra info we tack onto an elf_link_hash_entry. */
503 static void
504 elf64_x86_64_copy_indirect_symbol (struct elf_backend_data *bed,
505 struct elf_link_hash_entry *dir,
506 struct elf_link_hash_entry *ind)
508 struct elf64_x86_64_link_hash_entry *edir, *eind;
510 edir = (struct elf64_x86_64_link_hash_entry *) dir;
511 eind = (struct elf64_x86_64_link_hash_entry *) ind;
513 if (eind->dyn_relocs != NULL)
515 if (edir->dyn_relocs != NULL)
517 struct elf64_x86_64_dyn_relocs **pp;
518 struct elf64_x86_64_dyn_relocs *p;
520 if (ind->root.type == bfd_link_hash_indirect)
521 abort ();
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; )
527 struct elf64_x86_64_dyn_relocs *q;
529 for (q = edir->dyn_relocs; q != NULL; q = q->next)
530 if (q->sec == p->sec)
532 q->pc_count += p->pc_count;
533 q->count += p->count;
534 *pp = p->next;
535 break;
537 if (q == NULL)
538 pp = &p->next;
540 *pp = edir->dyn_relocs;
543 edir->dyn_relocs = eind->dyn_relocs;
544 eind->dyn_relocs = NULL;
547 if (ind->root.type == bfd_link_hash_indirect
548 && dir->got.refcount <= 0)
550 edir->tls_type = eind->tls_type;
551 eind->tls_type = GOT_UNKNOWN;
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 else
565 _bfd_elf_link_hash_copy_indirect (bed, dir, ind);
568 static bfd_boolean
569 elf64_x86_64_mkobject (bfd *abfd)
571 bfd_size_type amt = sizeof (struct elf64_x86_64_obj_tdata);
572 abfd->tdata.any = bfd_zalloc (abfd, amt);
573 if (abfd->tdata.any == NULL)
574 return FALSE;
575 return TRUE;
578 static bfd_boolean
579 elf64_x86_64_elf_object_p (bfd *abfd)
581 /* Allocate our special target data. */
582 struct elf64_x86_64_obj_tdata *new_tdata;
583 bfd_size_type amt = sizeof (struct elf64_x86_64_obj_tdata);
584 new_tdata = bfd_zalloc (abfd, amt);
585 if (new_tdata == NULL)
586 return FALSE;
587 new_tdata->root = *abfd->tdata.elf_obj_data;
588 abfd->tdata.any = new_tdata;
589 /* Set the right machine number for an x86-64 elf64 file. */
590 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
591 return TRUE;
594 static int
595 elf64_x86_64_tls_transition (struct bfd_link_info *info, int r_type, int is_local)
597 if (info->shared)
598 return r_type;
600 switch (r_type)
602 case R_X86_64_TLSGD:
603 case R_X86_64_GOTTPOFF:
604 if (is_local)
605 return R_X86_64_TPOFF32;
606 return R_X86_64_GOTTPOFF;
607 case R_X86_64_TLSLD:
608 return R_X86_64_TPOFF32;
611 return r_type;
614 /* Look through the relocs for a section during the first phase, and
615 calculate needed space in the global offset table, procedure
616 linkage table, and dynamic reloc sections. */
618 static bfd_boolean
619 elf64_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info, asection *sec,
620 const Elf_Internal_Rela *relocs)
622 struct elf64_x86_64_link_hash_table *htab;
623 Elf_Internal_Shdr *symtab_hdr;
624 struct elf_link_hash_entry **sym_hashes;
625 const Elf_Internal_Rela *rel;
626 const Elf_Internal_Rela *rel_end;
627 asection *sreloc;
629 if (info->relocatable)
630 return TRUE;
632 htab = elf64_x86_64_hash_table (info);
633 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
634 sym_hashes = elf_sym_hashes (abfd);
636 sreloc = NULL;
638 rel_end = relocs + sec->reloc_count;
639 for (rel = relocs; rel < rel_end; rel++)
641 unsigned int r_type;
642 unsigned long r_symndx;
643 struct elf_link_hash_entry *h;
645 r_symndx = ELF64_R_SYM (rel->r_info);
646 r_type = ELF64_R_TYPE (rel->r_info);
648 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
650 (*_bfd_error_handler) (_("%s: bad symbol index: %d"),
651 bfd_archive_filename (abfd),
652 r_symndx);
653 return FALSE;
656 if (r_symndx < symtab_hdr->sh_info)
657 h = NULL;
658 else
659 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
661 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
662 switch (r_type)
664 case R_X86_64_TLSLD:
665 htab->tls_ld_got.refcount += 1;
666 goto create_got;
668 case R_X86_64_TPOFF32:
669 if (info->shared)
671 (*_bfd_error_handler)
672 (_("%s: relocation %s can not be used when making a shared object; recompile with -fPIC"),
673 bfd_archive_filename (abfd),
674 x86_64_elf_howto_table[r_type].name);
675 bfd_set_error (bfd_error_bad_value);
676 return FALSE;
678 break;
680 case R_X86_64_GOTTPOFF:
681 if (info->shared)
682 info->flags |= DF_STATIC_TLS;
683 /* Fall through */
685 case R_X86_64_GOT32:
686 case R_X86_64_GOTPCREL:
687 case R_X86_64_TLSGD:
688 /* This symbol requires a global offset table entry. */
690 int tls_type, old_tls_type;
692 switch (r_type)
694 default: tls_type = GOT_NORMAL; break;
695 case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
696 case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
699 if (h != NULL)
701 h->got.refcount += 1;
702 old_tls_type = elf64_x86_64_hash_entry (h)->tls_type;
704 else
706 bfd_signed_vma *local_got_refcounts;
708 /* This is a global offset table entry for a local symbol. */
709 local_got_refcounts = elf_local_got_refcounts (abfd);
710 if (local_got_refcounts == NULL)
712 bfd_size_type size;
714 size = symtab_hdr->sh_info;
715 size *= sizeof (bfd_signed_vma) + sizeof (char);
716 local_got_refcounts = ((bfd_signed_vma *)
717 bfd_zalloc (abfd, size));
718 if (local_got_refcounts == NULL)
719 return FALSE;
720 elf_local_got_refcounts (abfd) = local_got_refcounts;
721 elf64_x86_64_local_got_tls_type (abfd)
722 = (char *) (local_got_refcounts + symtab_hdr->sh_info);
724 local_got_refcounts[r_symndx] += 1;
725 old_tls_type
726 = elf64_x86_64_local_got_tls_type (abfd) [r_symndx];
729 /* If a TLS symbol is accessed using IE at least once,
730 there is no point to use dynamic model for it. */
731 if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
732 && (old_tls_type != GOT_TLS_GD || tls_type != GOT_TLS_IE))
734 if (old_tls_type == GOT_TLS_IE && tls_type == GOT_TLS_GD)
735 tls_type = old_tls_type;
736 else
738 (*_bfd_error_handler)
739 (_("%s: %s' accessed both as normal and thread local symbol"),
740 bfd_archive_filename (abfd),
741 h ? h->root.root.string : "<local>");
742 return FALSE;
746 if (old_tls_type != tls_type)
748 if (h != NULL)
749 elf64_x86_64_hash_entry (h)->tls_type = tls_type;
750 else
751 elf64_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
754 /* Fall through */
756 //case R_X86_64_GOTPCREL:
757 create_got:
758 if (htab->sgot == NULL)
760 if (htab->elf.dynobj == NULL)
761 htab->elf.dynobj = abfd;
762 if (!create_got_section (htab->elf.dynobj, info))
763 return FALSE;
765 break;
767 case R_X86_64_PLT32:
768 /* This symbol requires a procedure linkage table entry. We
769 actually build the entry in adjust_dynamic_symbol,
770 because this might be a case of linking PIC code which is
771 never referenced by a dynamic object, in which case we
772 don't need to generate a procedure linkage table entry
773 after all. */
775 /* If this is a local symbol, we resolve it directly without
776 creating a procedure linkage table entry. */
777 if (h == NULL)
778 continue;
780 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
781 h->plt.refcount += 1;
782 break;
784 case R_X86_64_8:
785 case R_X86_64_16:
786 case R_X86_64_32:
787 case R_X86_64_32S:
788 /* Let's help debug shared library creation. These relocs
789 cannot be used in shared libs. Don't error out for
790 sections we don't care about, such as debug sections or
791 non-constant sections. */
792 if (info->shared
793 && (sec->flags & SEC_ALLOC) != 0
794 && (sec->flags & SEC_READONLY) != 0)
796 (*_bfd_error_handler)
797 (_("%s: relocation %s can not be used when making a shared object; recompile with -fPIC"),
798 bfd_archive_filename (abfd),
799 x86_64_elf_howto_table[r_type].name);
800 bfd_set_error (bfd_error_bad_value);
801 return FALSE;
803 /* Fall through. */
805 case R_X86_64_PC8:
806 case R_X86_64_PC16:
807 case R_X86_64_PC32:
808 case R_X86_64_64:
809 if (h != NULL && !info->shared)
811 /* If this reloc is in a read-only section, we might
812 need a copy reloc. We can't check reliably at this
813 stage whether the section is read-only, as input
814 sections have not yet been mapped to output sections.
815 Tentatively set the flag for now, and correct in
816 adjust_dynamic_symbol. */
817 h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF;
819 /* We may need a .plt entry if the function this reloc
820 refers to is in a shared lib. */
821 h->plt.refcount += 1;
824 /* If we are creating a shared library, and this is a reloc
825 against a global symbol, or a non PC relative reloc
826 against a local symbol, then we need to copy the reloc
827 into the shared library. However, if we are linking with
828 -Bsymbolic, we do not need to copy a reloc against a
829 global symbol which is defined in an object we are
830 including in the link (i.e., DEF_REGULAR is set). At
831 this point we have not seen all the input files, so it is
832 possible that DEF_REGULAR is not set now but will be set
833 later (it is never cleared). In case of a weak definition,
834 DEF_REGULAR may be cleared later by a strong definition in
835 a shared library. We account for that possibility below by
836 storing information in the relocs_copied field of the hash
837 table entry. A similar situation occurs when creating
838 shared libraries and symbol visibility changes render the
839 symbol local.
841 If on the other hand, we are creating an executable, we
842 may need to keep relocations for symbols satisfied by a
843 dynamic library if we manage to avoid copy relocs for the
844 symbol. */
845 if ((info->shared
846 && (sec->flags & SEC_ALLOC) != 0
847 && (((r_type != R_X86_64_PC8)
848 && (r_type != R_X86_64_PC16)
849 && (r_type != R_X86_64_PC32))
850 || (h != NULL
851 && (! info->symbolic
852 || h->root.type == bfd_link_hash_defweak
853 || (h->elf_link_hash_flags
854 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
855 || (ELIMINATE_COPY_RELOCS
856 && !info->shared
857 && (sec->flags & SEC_ALLOC) != 0
858 && h != NULL
859 && (h->root.type == bfd_link_hash_defweak
860 || (h->elf_link_hash_flags
861 & ELF_LINK_HASH_DEF_REGULAR) == 0)))
863 struct elf64_x86_64_dyn_relocs *p;
864 struct elf64_x86_64_dyn_relocs **head;
866 /* We must copy these reloc types into the output file.
867 Create a reloc section in dynobj and make room for
868 this reloc. */
869 if (sreloc == NULL)
871 const char *name;
872 bfd *dynobj;
874 name = (bfd_elf_string_from_elf_section
875 (abfd,
876 elf_elfheader (abfd)->e_shstrndx,
877 elf_section_data (sec)->rel_hdr.sh_name));
878 if (name == NULL)
879 return FALSE;
881 if (strncmp (name, ".rela", 5) != 0
882 || strcmp (bfd_get_section_name (abfd, sec),
883 name + 5) != 0)
885 (*_bfd_error_handler)
886 (_("%s: bad relocation section name `%s\'"),
887 bfd_archive_filename (abfd), name);
890 if (htab->elf.dynobj == NULL)
891 htab->elf.dynobj = abfd;
893 dynobj = htab->elf.dynobj;
895 sreloc = bfd_get_section_by_name (dynobj, name);
896 if (sreloc == NULL)
898 flagword flags;
900 sreloc = bfd_make_section (dynobj, name);
901 flags = (SEC_HAS_CONTENTS | SEC_READONLY
902 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
903 if ((sec->flags & SEC_ALLOC) != 0)
904 flags |= SEC_ALLOC | SEC_LOAD;
905 if (sreloc == NULL
906 || ! bfd_set_section_flags (dynobj, sreloc, flags)
907 || ! bfd_set_section_alignment (dynobj, sreloc, 3))
908 return FALSE;
910 elf_section_data (sec)->sreloc = sreloc;
913 /* If this is a global symbol, we count the number of
914 relocations we need for this symbol. */
915 if (h != NULL)
917 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs;
919 else
921 /* Track dynamic relocs needed for local syms too.
922 We really need local syms available to do this
923 easily. Oh well. */
925 asection *s;
926 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
927 sec, r_symndx);
928 if (s == NULL)
929 return FALSE;
931 head = ((struct elf64_x86_64_dyn_relocs **)
932 &elf_section_data (s)->local_dynrel);
935 p = *head;
936 if (p == NULL || p->sec != sec)
938 bfd_size_type amt = sizeof *p;
939 p = ((struct elf64_x86_64_dyn_relocs *)
940 bfd_alloc (htab->elf.dynobj, amt));
941 if (p == NULL)
942 return FALSE;
943 p->next = *head;
944 *head = p;
945 p->sec = sec;
946 p->count = 0;
947 p->pc_count = 0;
950 p->count += 1;
951 if (r_type == R_X86_64_PC8
952 || r_type == R_X86_64_PC16
953 || r_type == R_X86_64_PC32)
954 p->pc_count += 1;
956 break;
958 /* This relocation describes the C++ object vtable hierarchy.
959 Reconstruct it for later use during GC. */
960 case R_X86_64_GNU_VTINHERIT:
961 if (!_bfd_elf64_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
962 return FALSE;
963 break;
965 /* This relocation describes which C++ vtable entries are actually
966 used. Record for later use during GC. */
967 case R_X86_64_GNU_VTENTRY:
968 if (!_bfd_elf64_gc_record_vtentry (abfd, sec, h, rel->r_addend))
969 return FALSE;
970 break;
972 default:
973 break;
977 return TRUE;
980 /* Return the section that should be marked against GC for a given
981 relocation. */
983 static asection *
984 elf64_x86_64_gc_mark_hook (asection *sec,
985 struct bfd_link_info *info ATTRIBUTE_UNUSED,
986 Elf_Internal_Rela *rel,
987 struct elf_link_hash_entry *h,
988 Elf_Internal_Sym *sym)
990 if (h != NULL)
992 switch (ELF64_R_TYPE (rel->r_info))
994 case R_X86_64_GNU_VTINHERIT:
995 case R_X86_64_GNU_VTENTRY:
996 break;
998 default:
999 switch (h->root.type)
1001 case bfd_link_hash_defined:
1002 case bfd_link_hash_defweak:
1003 return h->root.u.def.section;
1005 case bfd_link_hash_common:
1006 return h->root.u.c.p->section;
1008 default:
1009 break;
1013 else
1014 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
1016 return NULL;
1019 /* Update the got entry reference counts for the section being removed. */
1021 static bfd_boolean
1022 elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
1023 asection *sec, const Elf_Internal_Rela *relocs)
1025 Elf_Internal_Shdr *symtab_hdr;
1026 struct elf_link_hash_entry **sym_hashes;
1027 bfd_signed_vma *local_got_refcounts;
1028 const Elf_Internal_Rela *rel, *relend;
1030 elf_section_data (sec)->local_dynrel = NULL;
1032 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1033 sym_hashes = elf_sym_hashes (abfd);
1034 local_got_refcounts = elf_local_got_refcounts (abfd);
1036 relend = relocs + sec->reloc_count;
1037 for (rel = relocs; rel < relend; rel++)
1039 unsigned long r_symndx;
1040 unsigned int r_type;
1041 struct elf_link_hash_entry *h = NULL;
1043 r_symndx = ELF64_R_SYM (rel->r_info);
1044 if (r_symndx >= symtab_hdr->sh_info)
1046 struct elf64_x86_64_link_hash_entry *eh;
1047 struct elf64_x86_64_dyn_relocs **pp;
1048 struct elf64_x86_64_dyn_relocs *p;
1050 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1051 eh = (struct elf64_x86_64_link_hash_entry *) h;
1053 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1054 if (p->sec == sec)
1056 /* Everything must go for SEC. */
1057 *pp = p->next;
1058 break;
1062 r_type = ELF64_R_TYPE (rel->r_info);
1063 r_type = elf64_x86_64_tls_transition (info, r_type, h != NULL);
1064 switch (r_type)
1066 case R_X86_64_TLSLD:
1067 if (elf64_x86_64_hash_table (info)->tls_ld_got.refcount > 0)
1068 elf64_x86_64_hash_table (info)->tls_ld_got.refcount -= 1;
1069 break;
1071 case R_X86_64_TLSGD:
1072 case R_X86_64_GOTTPOFF:
1073 case R_X86_64_GOT32:
1074 case R_X86_64_GOTPCREL:
1075 if (h != NULL)
1077 if (h->got.refcount > 0)
1078 h->got.refcount -= 1;
1080 else if (local_got_refcounts != NULL)
1082 if (local_got_refcounts[r_symndx] > 0)
1083 local_got_refcounts[r_symndx] -= 1;
1085 break;
1087 case R_X86_64_8:
1088 case R_X86_64_16:
1089 case R_X86_64_32:
1090 case R_X86_64_64:
1091 case R_X86_64_32S:
1092 case R_X86_64_PC8:
1093 case R_X86_64_PC16:
1094 case R_X86_64_PC32:
1095 if (info->shared)
1096 break;
1097 /* Fall thru */
1099 case R_X86_64_PLT32:
1100 if (h != NULL)
1102 if (h->plt.refcount > 0)
1103 h->plt.refcount -= 1;
1105 break;
1107 default:
1108 break;
1112 return TRUE;
1115 /* Adjust a symbol defined by a dynamic object and referenced by a
1116 regular object. The current definition is in some section of the
1117 dynamic object, but we're not including those sections. We have to
1118 change the definition to something the rest of the link can
1119 understand. */
1121 static bfd_boolean
1122 elf64_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
1123 struct elf_link_hash_entry *h)
1125 struct elf64_x86_64_link_hash_table *htab;
1126 asection *s;
1127 unsigned int power_of_two;
1129 /* If this is a function, put it in the procedure linkage table. We
1130 will fill in the contents of the procedure linkage table later,
1131 when we know the address of the .got section. */
1132 if (h->type == STT_FUNC
1133 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
1135 if (h->plt.refcount <= 0
1136 || SYMBOL_CALLS_LOCAL (info, h)
1137 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1138 && h->root.type == bfd_link_hash_undefweak))
1140 /* This case can occur if we saw a PLT32 reloc in an input
1141 file, but the symbol was never referred to by a dynamic
1142 object, or if all references were garbage collected. In
1143 such a case, we don't actually need to build a procedure
1144 linkage table, and we can just do a PC32 reloc instead. */
1145 h->plt.offset = (bfd_vma) -1;
1146 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1149 return TRUE;
1151 else
1152 /* It's possible that we incorrectly decided a .plt reloc was
1153 needed for an R_X86_64_PC32 reloc to a non-function sym in
1154 check_relocs. We can't decide accurately between function and
1155 non-function syms in check-relocs; Objects loaded later in
1156 the link may change h->type. So fix it now. */
1157 h->plt.offset = (bfd_vma) -1;
1159 /* If this is a weak symbol, and there is a real definition, the
1160 processor independent code will have arranged for us to see the
1161 real definition first, and we can just use the same value. */
1162 if (h->weakdef != NULL)
1164 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
1165 || h->weakdef->root.type == bfd_link_hash_defweak);
1166 h->root.u.def.section = h->weakdef->root.u.def.section;
1167 h->root.u.def.value = h->weakdef->root.u.def.value;
1168 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1169 h->elf_link_hash_flags
1170 = ((h->elf_link_hash_flags & ~ELF_LINK_NON_GOT_REF)
1171 | (h->weakdef->elf_link_hash_flags & ELF_LINK_NON_GOT_REF));
1172 return TRUE;
1175 /* This is a reference to a symbol defined by a dynamic object which
1176 is not a function. */
1178 /* If we are creating a shared library, we must presume that the
1179 only references to the symbol are via the global offset table.
1180 For such cases we need not do anything here; the relocations will
1181 be handled correctly by relocate_section. */
1182 if (info->shared)
1183 return TRUE;
1185 /* If there are no references to this symbol that do not use the
1186 GOT, we don't need to generate a copy reloc. */
1187 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0)
1188 return TRUE;
1190 /* If -z nocopyreloc was given, we won't generate them either. */
1191 if (info->nocopyreloc)
1193 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1194 return TRUE;
1197 if (ELIMINATE_COPY_RELOCS)
1199 struct elf64_x86_64_link_hash_entry * eh;
1200 struct elf64_x86_64_dyn_relocs *p;
1202 eh = (struct elf64_x86_64_link_hash_entry *) h;
1203 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1205 s = p->sec->output_section;
1206 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1207 break;
1210 /* If we didn't find any dynamic relocs in read-only sections, then
1211 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1212 if (p == NULL)
1214 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1215 return TRUE;
1219 /* We must allocate the symbol in our .dynbss section, which will
1220 become part of the .bss section of the executable. There will be
1221 an entry for this symbol in the .dynsym section. The dynamic
1222 object will contain position independent code, so all references
1223 from the dynamic object to this symbol will go through the global
1224 offset table. The dynamic linker will use the .dynsym entry to
1225 determine the address it must put in the global offset table, so
1226 both the dynamic object and the regular object will refer to the
1227 same memory location for the variable. */
1229 htab = elf64_x86_64_hash_table (info);
1231 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
1232 to copy the initial value out of the dynamic object and into the
1233 runtime process image. */
1234 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1236 htab->srelbss->_raw_size += sizeof (Elf64_External_Rela);
1237 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
1240 /* We need to figure out the alignment required for this symbol. I
1241 have no idea how ELF linkers handle this. 16-bytes is the size
1242 of the largest type that requires hard alignment -- long double. */
1243 /* FIXME: This is VERY ugly. Should be fixed for all architectures using
1244 this construct. */
1245 power_of_two = bfd_log2 (h->size);
1246 if (power_of_two > 4)
1247 power_of_two = 4;
1249 /* Apply the required alignment. */
1250 s = htab->sdynbss;
1251 s->_raw_size = BFD_ALIGN (s->_raw_size, (bfd_size_type) (1 << power_of_two));
1252 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1254 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1255 return FALSE;
1258 /* Define the symbol as being at this point in the section. */
1259 h->root.u.def.section = s;
1260 h->root.u.def.value = s->_raw_size;
1262 /* Increment the section size to make room for the symbol. */
1263 s->_raw_size += h->size;
1265 return TRUE;
1268 /* This is the condition under which elf64_x86_64_finish_dynamic_symbol
1269 will be called from elflink.h. If elflink.h doesn't call our
1270 finish_dynamic_symbol routine, we'll need to do something about
1271 initializing any .plt and .got entries in elf64_x86_64_relocate_section. */
1272 #define WILL_CALL_FINISH_DYNAMIC_SYMBOL(DYN, SHARED, H) \
1273 ((DYN) \
1274 && ((SHARED) \
1275 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) \
1276 && ((H)->dynindx != -1 \
1277 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0))
1279 /* Allocate space in .plt, .got and associated reloc sections for
1280 dynamic relocs. */
1282 static bfd_boolean
1283 allocate_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1285 struct bfd_link_info *info;
1286 struct elf64_x86_64_link_hash_table *htab;
1287 struct elf64_x86_64_link_hash_entry *eh;
1288 struct elf64_x86_64_dyn_relocs *p;
1290 if (h->root.type == bfd_link_hash_indirect)
1291 return TRUE;
1293 if (h->root.type == bfd_link_hash_warning)
1294 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1296 info = (struct bfd_link_info *) inf;
1297 htab = elf64_x86_64_hash_table (info);
1299 if (htab->elf.dynamic_sections_created
1300 && h->plt.refcount > 0)
1302 /* Make sure this symbol is output as a dynamic symbol.
1303 Undefined weak syms won't yet be marked as dynamic. */
1304 if (h->dynindx == -1
1305 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1307 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1308 return FALSE;
1311 if (info->shared
1312 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
1314 asection *s = htab->splt;
1316 /* If this is the first .plt entry, make room for the special
1317 first entry. */
1318 if (s->_raw_size == 0)
1319 s->_raw_size += PLT_ENTRY_SIZE;
1321 h->plt.offset = s->_raw_size;
1323 /* If this symbol is not defined in a regular file, and we are
1324 not generating a shared library, then set the symbol to this
1325 location in the .plt. This is required to make function
1326 pointers compare as equal between the normal executable and
1327 the shared library. */
1328 if (! info->shared
1329 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1331 h->root.u.def.section = s;
1332 h->root.u.def.value = h->plt.offset;
1335 /* Make room for this entry. */
1336 s->_raw_size += PLT_ENTRY_SIZE;
1338 /* We also need to make an entry in the .got.plt section, which
1339 will be placed in the .got section by the linker script. */
1340 htab->sgotplt->_raw_size += GOT_ENTRY_SIZE;
1342 /* We also need to make an entry in the .rela.plt section. */
1343 htab->srelplt->_raw_size += sizeof (Elf64_External_Rela);
1345 else
1347 h->plt.offset = (bfd_vma) -1;
1348 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1351 else
1353 h->plt.offset = (bfd_vma) -1;
1354 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1357 /* If R_X86_64_GOTTPOFF symbol is now local to the binary,
1358 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
1359 if (h->got.refcount > 0
1360 && !info->shared
1361 && h->dynindx == -1
1362 && elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
1363 h->got.offset = (bfd_vma) -1;
1364 else if (h->got.refcount > 0)
1366 asection *s;
1367 bfd_boolean dyn;
1368 int tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1370 /* Make sure this symbol is output as a dynamic symbol.
1371 Undefined weak syms won't yet be marked as dynamic. */
1372 if (h->dynindx == -1
1373 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1375 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1376 return FALSE;
1379 s = htab->sgot;
1380 h->got.offset = s->_raw_size;
1381 s->_raw_size += GOT_ENTRY_SIZE;
1382 /* R_X86_64_TLSGD needs 2 consecutive GOT slots. */
1383 if (tls_type == GOT_TLS_GD)
1384 s->_raw_size += GOT_ENTRY_SIZE;
1385 dyn = htab->elf.dynamic_sections_created;
1386 /* R_X86_64_TLSGD needs one dynamic relocation if local symbol
1387 and two if global.
1388 R_X86_64_GOTTPOFF needs one dynamic relocation. */
1389 if ((tls_type == GOT_TLS_GD && h->dynindx == -1)
1390 || tls_type == GOT_TLS_IE)
1391 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1392 else if (tls_type == GOT_TLS_GD)
1393 htab->srelgot->_raw_size += 2 * sizeof (Elf64_External_Rela);
1394 else if ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1395 || h->root.type != bfd_link_hash_undefweak)
1396 && (info->shared
1397 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
1398 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1400 else
1401 h->got.offset = (bfd_vma) -1;
1403 eh = (struct elf64_x86_64_link_hash_entry *) h;
1404 if (eh->dyn_relocs == NULL)
1405 return TRUE;
1407 /* In the shared -Bsymbolic case, discard space allocated for
1408 dynamic pc-relative relocs against symbols which turn out to be
1409 defined in regular objects. For the normal shared case, discard
1410 space for pc-relative relocs that have become local due to symbol
1411 visibility changes. */
1413 if (info->shared)
1415 /* Relocs that use pc_count are those that appear on a call
1416 insn, or certain REL relocs that can generated via assembly.
1417 We want calls to protected symbols to resolve directly to the
1418 function rather than going via the plt. If people want
1419 function pointer comparisons to work as expected then they
1420 should avoid writing weird assembly. */
1421 if (SYMBOL_CALLS_LOCAL (info, h))
1423 struct elf64_x86_64_dyn_relocs **pp;
1425 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1427 p->count -= p->pc_count;
1428 p->pc_count = 0;
1429 if (p->count == 0)
1430 *pp = p->next;
1431 else
1432 pp = &p->next;
1436 /* Also discard relocs on undefined weak syms with non-default
1437 visibility. */
1438 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1439 && h->root.type == bfd_link_hash_undefweak)
1440 eh->dyn_relocs = NULL;
1442 else if (ELIMINATE_COPY_RELOCS)
1444 /* For the non-shared case, discard space for relocs against
1445 symbols which turn out to need copy relocs or are not
1446 dynamic. */
1448 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1449 && (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1450 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1451 || (htab->elf.dynamic_sections_created
1452 && (h->root.type == bfd_link_hash_undefweak
1453 || h->root.type == bfd_link_hash_undefined))))
1455 /* Make sure this symbol is output as a dynamic symbol.
1456 Undefined weak syms won't yet be marked as dynamic. */
1457 if (h->dynindx == -1
1458 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1460 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1461 return FALSE;
1464 /* If that succeeded, we know we'll be keeping all the
1465 relocs. */
1466 if (h->dynindx != -1)
1467 goto keep;
1470 eh->dyn_relocs = NULL;
1472 keep: ;
1475 /* Finally, allocate space. */
1476 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1478 asection *sreloc = elf_section_data (p->sec)->sreloc;
1479 sreloc->_raw_size += p->count * sizeof (Elf64_External_Rela);
1482 return TRUE;
1485 /* Find any dynamic relocs that apply to read-only sections. */
1487 static bfd_boolean
1488 readonly_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1490 struct elf64_x86_64_link_hash_entry *eh;
1491 struct elf64_x86_64_dyn_relocs *p;
1493 if (h->root.type == bfd_link_hash_warning)
1494 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1496 eh = (struct elf64_x86_64_link_hash_entry *) h;
1497 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1499 asection *s = p->sec->output_section;
1501 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1503 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1505 info->flags |= DF_TEXTREL;
1507 /* Not an error, just cut short the traversal. */
1508 return FALSE;
1511 return TRUE;
1514 /* Set the sizes of the dynamic sections. */
1516 static bfd_boolean
1517 elf64_x86_64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
1518 struct bfd_link_info *info)
1520 struct elf64_x86_64_link_hash_table *htab;
1521 bfd *dynobj;
1522 asection *s;
1523 bfd_boolean relocs;
1524 bfd *ibfd;
1526 htab = elf64_x86_64_hash_table (info);
1527 dynobj = htab->elf.dynobj;
1528 if (dynobj == NULL)
1529 abort ();
1531 if (htab->elf.dynamic_sections_created)
1533 /* Set the contents of the .interp section to the interpreter. */
1534 if (info->executable)
1536 s = bfd_get_section_by_name (dynobj, ".interp");
1537 if (s == NULL)
1538 abort ();
1539 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
1540 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1544 /* Set up .got offsets for local syms, and space for local dynamic
1545 relocs. */
1546 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1548 bfd_signed_vma *local_got;
1549 bfd_signed_vma *end_local_got;
1550 char *local_tls_type;
1551 bfd_size_type locsymcount;
1552 Elf_Internal_Shdr *symtab_hdr;
1553 asection *srel;
1555 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1556 continue;
1558 for (s = ibfd->sections; s != NULL; s = s->next)
1560 struct elf64_x86_64_dyn_relocs *p;
1562 for (p = *((struct elf64_x86_64_dyn_relocs **)
1563 &elf_section_data (s)->local_dynrel);
1564 p != NULL;
1565 p = p->next)
1567 if (!bfd_is_abs_section (p->sec)
1568 && bfd_is_abs_section (p->sec->output_section))
1570 /* Input section has been discarded, either because
1571 it is a copy of a linkonce section or due to
1572 linker script /DISCARD/, so we'll be discarding
1573 the relocs too. */
1575 else if (p->count != 0)
1577 srel = elf_section_data (p->sec)->sreloc;
1578 srel->_raw_size += p->count * sizeof (Elf64_External_Rela);
1579 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1580 info->flags |= DF_TEXTREL;
1586 local_got = elf_local_got_refcounts (ibfd);
1587 if (!local_got)
1588 continue;
1590 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1591 locsymcount = symtab_hdr->sh_info;
1592 end_local_got = local_got + locsymcount;
1593 local_tls_type = elf64_x86_64_local_got_tls_type (ibfd);
1594 s = htab->sgot;
1595 srel = htab->srelgot;
1596 for (; local_got < end_local_got; ++local_got, ++local_tls_type)
1598 if (*local_got > 0)
1600 *local_got = s->_raw_size;
1601 s->_raw_size += GOT_ENTRY_SIZE;
1602 if (*local_tls_type == GOT_TLS_GD)
1603 s->_raw_size += GOT_ENTRY_SIZE;
1604 if (info->shared
1605 || *local_tls_type == GOT_TLS_GD
1606 || *local_tls_type == GOT_TLS_IE)
1607 srel->_raw_size += sizeof (Elf64_External_Rela);
1609 else
1610 *local_got = (bfd_vma) -1;
1614 if (htab->tls_ld_got.refcount > 0)
1616 /* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD
1617 relocs. */
1618 htab->tls_ld_got.offset = htab->sgot->_raw_size;
1619 htab->sgot->_raw_size += 2 * GOT_ENTRY_SIZE;
1620 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1622 else
1623 htab->tls_ld_got.offset = -1;
1625 /* Allocate global sym .plt and .got entries, and space for global
1626 sym dynamic relocs. */
1627 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1629 /* We now have determined the sizes of the various dynamic sections.
1630 Allocate memory for them. */
1631 relocs = FALSE;
1632 for (s = dynobj->sections; s != NULL; s = s->next)
1634 if ((s->flags & SEC_LINKER_CREATED) == 0)
1635 continue;
1637 if (s == htab->splt
1638 || s == htab->sgot
1639 || s == htab->sgotplt)
1641 /* Strip this section if we don't need it; see the
1642 comment below. */
1644 else if (strncmp (bfd_get_section_name (dynobj, s), ".rela", 5) == 0)
1646 if (s->_raw_size != 0 && s != htab->srelplt)
1647 relocs = TRUE;
1649 /* We use the reloc_count field as a counter if we need
1650 to copy relocs into the output file. */
1651 s->reloc_count = 0;
1653 else
1655 /* It's not one of our sections, so don't allocate space. */
1656 continue;
1659 if (s->_raw_size == 0)
1661 /* If we don't need this section, strip it from the
1662 output file. This is mostly to handle .rela.bss and
1663 .rela.plt. We must create both sections in
1664 create_dynamic_sections, because they must be created
1665 before the linker maps input sections to output
1666 sections. The linker does that before
1667 adjust_dynamic_symbol is called, and it is that
1668 function which decides whether anything needs to go
1669 into these sections. */
1671 _bfd_strip_section_from_output (info, s);
1672 continue;
1675 /* Allocate memory for the section contents. We use bfd_zalloc
1676 here in case unused entries are not reclaimed before the
1677 section's contents are written out. This should not happen,
1678 but this way if it does, we get a R_X86_64_NONE reloc instead
1679 of garbage. */
1680 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
1681 if (s->contents == NULL)
1682 return FALSE;
1685 if (htab->elf.dynamic_sections_created)
1687 /* Add some entries to the .dynamic section. We fill in the
1688 values later, in elf64_x86_64_finish_dynamic_sections, but we
1689 must add the entries now so that we get the correct size for
1690 the .dynamic section. The DT_DEBUG entry is filled in by the
1691 dynamic linker and used by the debugger. */
1692 #define add_dynamic_entry(TAG, VAL) \
1693 bfd_elf64_add_dynamic_entry (info, (bfd_vma) (TAG), (bfd_vma) (VAL))
1695 if (info->executable)
1697 if (!add_dynamic_entry (DT_DEBUG, 0))
1698 return FALSE;
1701 if (htab->splt->_raw_size != 0)
1703 if (!add_dynamic_entry (DT_PLTGOT, 0)
1704 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1705 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1706 || !add_dynamic_entry (DT_JMPREL, 0))
1707 return FALSE;
1710 if (relocs)
1712 if (!add_dynamic_entry (DT_RELA, 0)
1713 || !add_dynamic_entry (DT_RELASZ, 0)
1714 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
1715 return FALSE;
1717 /* If any dynamic relocs apply to a read-only section,
1718 then we need a DT_TEXTREL entry. */
1719 if ((info->flags & DF_TEXTREL) == 0)
1720 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
1721 (PTR) info);
1723 if ((info->flags & DF_TEXTREL) != 0)
1725 if (!add_dynamic_entry (DT_TEXTREL, 0))
1726 return FALSE;
1730 #undef add_dynamic_entry
1732 return TRUE;
1735 /* Return the base VMA address which should be subtracted from real addresses
1736 when resolving @dtpoff relocation.
1737 This is PT_TLS segment p_vaddr. */
1739 static bfd_vma
1740 dtpoff_base (struct bfd_link_info *info)
1742 /* If tls_segment is NULL, we should have signalled an error already. */
1743 if (elf_hash_table (info)->tls_segment == NULL)
1744 return 0;
1745 return elf_hash_table (info)->tls_segment->start;
1748 /* Return the relocation value for @tpoff relocation
1749 if STT_TLS virtual address is ADDRESS. */
1751 static bfd_vma
1752 tpoff (struct bfd_link_info *info, bfd_vma address)
1754 struct elf_link_tls_segment *tls_segment
1755 = elf_hash_table (info)->tls_segment;
1757 /* If tls_segment is NULL, we should have signalled an error already. */
1758 if (tls_segment == NULL)
1759 return 0;
1760 return address - align_power (tls_segment->size, tls_segment->align)
1761 - tls_segment->start;
1764 /* Relocate an x86_64 ELF section. */
1766 static bfd_boolean
1767 elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
1768 bfd *input_bfd, asection *input_section,
1769 bfd_byte *contents, Elf_Internal_Rela *relocs,
1770 Elf_Internal_Sym *local_syms,
1771 asection **local_sections)
1773 struct elf64_x86_64_link_hash_table *htab;
1774 Elf_Internal_Shdr *symtab_hdr;
1775 struct elf_link_hash_entry **sym_hashes;
1776 bfd_vma *local_got_offsets;
1777 Elf_Internal_Rela *rel;
1778 Elf_Internal_Rela *relend;
1780 if (info->relocatable)
1781 return TRUE;
1783 htab = elf64_x86_64_hash_table (info);
1784 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1785 sym_hashes = elf_sym_hashes (input_bfd);
1786 local_got_offsets = elf_local_got_offsets (input_bfd);
1788 rel = relocs;
1789 relend = relocs + input_section->reloc_count;
1790 for (; rel < relend; rel++)
1792 unsigned int r_type;
1793 reloc_howto_type *howto;
1794 unsigned long r_symndx;
1795 struct elf_link_hash_entry *h;
1796 Elf_Internal_Sym *sym;
1797 asection *sec;
1798 bfd_vma off;
1799 bfd_vma relocation;
1800 bfd_boolean unresolved_reloc;
1801 bfd_reloc_status_type r;
1802 int tls_type;
1804 r_type = ELF64_R_TYPE (rel->r_info);
1805 if (r_type == (int) R_X86_64_GNU_VTINHERIT
1806 || r_type == (int) R_X86_64_GNU_VTENTRY)
1807 continue;
1809 if (r_type >= R_X86_64_max)
1811 bfd_set_error (bfd_error_bad_value);
1812 return FALSE;
1815 howto = x86_64_elf_howto_table + r_type;
1816 r_symndx = ELF64_R_SYM (rel->r_info);
1817 h = NULL;
1818 sym = NULL;
1819 sec = NULL;
1820 unresolved_reloc = FALSE;
1821 if (r_symndx < symtab_hdr->sh_info)
1823 sym = local_syms + r_symndx;
1824 sec = local_sections[r_symndx];
1826 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, sec, rel);
1828 else
1830 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1831 while (h->root.type == bfd_link_hash_indirect
1832 || h->root.type == bfd_link_hash_warning)
1833 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1835 if (h->root.type == bfd_link_hash_defined
1836 || h->root.type == bfd_link_hash_defweak)
1838 sec = h->root.u.def.section;
1839 if (sec->output_section == NULL)
1841 /* Set a flag that will be cleared later if we find a
1842 relocation value for this symbol. output_section
1843 is typically NULL for symbols satisfied by a shared
1844 library. */
1845 unresolved_reloc = TRUE;
1846 relocation = 0;
1848 else
1849 relocation = (h->root.u.def.value
1850 + sec->output_section->vma
1851 + sec->output_offset);
1853 else if (h->root.type == bfd_link_hash_undefweak)
1854 relocation = 0;
1855 else if (!info->executable
1856 && !info->no_undefined
1857 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
1858 relocation = 0;
1859 else
1861 if (! ((*info->callbacks->undefined_symbol)
1862 (info, h->root.root.string, input_bfd,
1863 input_section, rel->r_offset,
1864 (!info->shared || info->no_undefined
1865 || ELF_ST_VISIBILITY (h->other)))))
1866 return FALSE;
1867 relocation = 0;
1870 /* When generating a shared object, the relocations handled here are
1871 copied into the output file to be resolved at run time. */
1872 switch (r_type)
1874 case R_X86_64_GOT32:
1875 /* Relocation is to the entry for this symbol in the global
1876 offset table. */
1877 case R_X86_64_GOTPCREL:
1878 /* Use global offset table as symbol value. */
1879 if (htab->sgot == NULL)
1880 abort ();
1882 if (h != NULL)
1884 bfd_boolean dyn;
1886 off = h->got.offset;
1887 dyn = htab->elf.dynamic_sections_created;
1889 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
1890 || (info->shared
1891 && SYMBOL_REFERENCES_LOCAL (info, h))
1892 || (ELF_ST_VISIBILITY (h->other)
1893 && h->root.type == bfd_link_hash_undefweak))
1895 /* This is actually a static link, or it is a -Bsymbolic
1896 link and the symbol is defined locally, or the symbol
1897 was forced to be local because of a version file. We
1898 must initialize this entry in the global offset table.
1899 Since the offset must always be a multiple of 8, we
1900 use the least significant bit to record whether we
1901 have initialized it already.
1903 When doing a dynamic link, we create a .rela.got
1904 relocation entry to initialize the value. This is
1905 done in the finish_dynamic_symbol routine. */
1906 if ((off & 1) != 0)
1907 off &= ~1;
1908 else
1910 bfd_put_64 (output_bfd, relocation,
1911 htab->sgot->contents + off);
1912 h->got.offset |= 1;
1915 else
1916 unresolved_reloc = FALSE;
1918 else
1920 if (local_got_offsets == NULL)
1921 abort ();
1923 off = local_got_offsets[r_symndx];
1925 /* The offset must always be a multiple of 8. We use
1926 the least significant bit to record whether we have
1927 already generated the necessary reloc. */
1928 if ((off & 1) != 0)
1929 off &= ~1;
1930 else
1932 bfd_put_64 (output_bfd, relocation,
1933 htab->sgot->contents + off);
1935 if (info->shared)
1937 asection *s;
1938 Elf_Internal_Rela outrel;
1939 bfd_byte *loc;
1941 /* We need to generate a R_X86_64_RELATIVE reloc
1942 for the dynamic linker. */
1943 s = htab->srelgot;
1944 if (s == NULL)
1945 abort ();
1947 outrel.r_offset = (htab->sgot->output_section->vma
1948 + htab->sgot->output_offset
1949 + off);
1950 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
1951 outrel.r_addend = relocation;
1952 loc = s->contents;
1953 loc += s->reloc_count++ * sizeof (Elf64_External_Rela);
1954 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
1957 local_got_offsets[r_symndx] |= 1;
1961 if (off >= (bfd_vma) -2)
1962 abort ();
1964 relocation = htab->sgot->output_offset + off;
1965 if (r_type == R_X86_64_GOTPCREL)
1966 relocation += htab->sgot->output_section->vma;
1968 break;
1970 case R_X86_64_PLT32:
1971 /* Relocation is to the entry for this symbol in the
1972 procedure linkage table. */
1974 /* Resolve a PLT32 reloc against a local symbol directly,
1975 without using the procedure linkage table. */
1976 if (h == NULL)
1977 break;
1979 if (h->plt.offset == (bfd_vma) -1
1980 || htab->splt == NULL)
1982 /* We didn't make a PLT entry for this symbol. This
1983 happens when statically linking PIC code, or when
1984 using -Bsymbolic. */
1985 break;
1988 relocation = (htab->splt->output_section->vma
1989 + htab->splt->output_offset
1990 + h->plt.offset);
1991 unresolved_reloc = FALSE;
1992 break;
1994 case R_X86_64_PC8:
1995 case R_X86_64_PC16:
1996 case R_X86_64_PC32:
1997 case R_X86_64_8:
1998 case R_X86_64_16:
1999 case R_X86_64_32:
2000 case R_X86_64_64:
2001 /* FIXME: The ABI says the linker should make sure the value is
2002 the same when it's zeroextended to 64 bit. */
2004 /* r_symndx will be zero only for relocs against symbols
2005 from removed linkonce sections, or sections discarded by
2006 a linker script. */
2007 if (r_symndx == 0
2008 || (input_section->flags & SEC_ALLOC) == 0)
2009 break;
2011 if ((info->shared
2012 && (h == NULL
2013 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
2014 || h->root.type != bfd_link_hash_undefweak)
2015 && ((r_type != R_X86_64_PC8
2016 && r_type != R_X86_64_PC16
2017 && r_type != R_X86_64_PC32)
2018 || !SYMBOL_CALLS_LOCAL (info, h)))
2019 || (ELIMINATE_COPY_RELOCS
2020 && !info->shared
2021 && h != NULL
2022 && h->dynindx != -1
2023 && (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
2024 && (((h->elf_link_hash_flags
2025 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2026 && (h->elf_link_hash_flags
2027 & ELF_LINK_HASH_DEF_REGULAR) == 0)
2028 || h->root.type == bfd_link_hash_undefweak
2029 || h->root.type == bfd_link_hash_undefined)))
2031 Elf_Internal_Rela outrel;
2032 bfd_byte *loc;
2033 bfd_boolean skip, relocate;
2034 asection *sreloc;
2036 /* When generating a shared object, these relocations
2037 are copied into the output file to be resolved at run
2038 time. */
2039 skip = FALSE;
2040 relocate = FALSE;
2042 outrel.r_offset =
2043 _bfd_elf_section_offset (output_bfd, info, input_section,
2044 rel->r_offset);
2045 if (outrel.r_offset == (bfd_vma) -1)
2046 skip = TRUE;
2047 else if (outrel.r_offset == (bfd_vma) -2)
2048 skip = TRUE, relocate = TRUE;
2050 outrel.r_offset += (input_section->output_section->vma
2051 + input_section->output_offset);
2053 if (skip)
2054 memset (&outrel, 0, sizeof outrel);
2056 /* h->dynindx may be -1 if this symbol was marked to
2057 become local. */
2058 else if (h != NULL
2059 && h->dynindx != -1
2060 && (r_type == R_X86_64_PC8
2061 || r_type == R_X86_64_PC16
2062 || r_type == R_X86_64_PC32
2063 || !info->shared
2064 || !info->symbolic
2065 || (h->elf_link_hash_flags
2066 & ELF_LINK_HASH_DEF_REGULAR) == 0))
2068 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
2069 outrel.r_addend = rel->r_addend;
2071 else
2073 /* This symbol is local, or marked to become local. */
2074 if (r_type == R_X86_64_64)
2076 relocate = TRUE;
2077 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2078 outrel.r_addend = relocation + rel->r_addend;
2080 else
2082 long sindx;
2084 if (h == NULL)
2085 sec = local_sections[r_symndx];
2086 else
2088 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2089 || (h->root.type
2090 == bfd_link_hash_defweak));
2091 sec = h->root.u.def.section;
2093 if (sec != NULL && bfd_is_abs_section (sec))
2094 sindx = 0;
2095 else if (sec == NULL || sec->owner == NULL)
2097 bfd_set_error (bfd_error_bad_value);
2098 return FALSE;
2100 else
2102 asection *osec;
2104 osec = sec->output_section;
2105 sindx = elf_section_data (osec)->dynindx;
2106 BFD_ASSERT (sindx > 0);
2109 outrel.r_info = ELF64_R_INFO (sindx, r_type);
2110 outrel.r_addend = relocation + rel->r_addend;
2114 sreloc = elf_section_data (input_section)->sreloc;
2115 if (sreloc == NULL)
2116 abort ();
2118 loc = sreloc->contents;
2119 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
2120 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2122 /* If this reloc is against an external symbol, we do
2123 not want to fiddle with the addend. Otherwise, we
2124 need to include the symbol value so that it becomes
2125 an addend for the dynamic reloc. */
2126 if (! relocate)
2127 continue;
2130 break;
2132 case R_X86_64_TLSGD:
2133 case R_X86_64_GOTTPOFF:
2134 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
2135 tls_type = GOT_UNKNOWN;
2136 if (h == NULL && local_got_offsets)
2137 tls_type = elf64_x86_64_local_got_tls_type (input_bfd) [r_symndx];
2138 else if (h != NULL)
2140 tls_type = elf64_x86_64_hash_entry (h)->tls_type;
2141 if (!info->shared && h->dynindx == -1 && tls_type == GOT_TLS_IE)
2142 r_type = R_X86_64_TPOFF32;
2144 if (r_type == R_X86_64_TLSGD)
2146 if (tls_type == GOT_TLS_IE)
2147 r_type = R_X86_64_GOTTPOFF;
2150 if (r_type == R_X86_64_TPOFF32)
2152 BFD_ASSERT (! unresolved_reloc);
2153 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
2155 unsigned int i;
2156 static unsigned char tlsgd[8]
2157 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2159 /* GD->LE transition.
2160 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2161 .word 0x6666; rex64; call __tls_get_addr@plt
2162 Change it into:
2163 movq %fs:0, %rax
2164 leaq foo@tpoff(%rax), %rax */
2165 BFD_ASSERT (rel->r_offset >= 4);
2166 for (i = 0; i < 4; i++)
2167 BFD_ASSERT (bfd_get_8 (input_bfd,
2168 contents + rel->r_offset - 4 + i)
2169 == tlsgd[i]);
2170 BFD_ASSERT (rel->r_offset + 12 <= input_section->_raw_size);
2171 for (i = 0; i < 4; i++)
2172 BFD_ASSERT (bfd_get_8 (input_bfd,
2173 contents + rel->r_offset + 4 + i)
2174 == tlsgd[i+4]);
2175 BFD_ASSERT (rel + 1 < relend);
2176 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2177 memcpy (contents + rel->r_offset - 4,
2178 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0",
2179 16);
2180 bfd_put_32 (output_bfd, tpoff (info, relocation),
2181 contents + rel->r_offset + 8);
2182 /* Skip R_X86_64_PLT32. */
2183 rel++;
2184 continue;
2186 else
2188 unsigned int val, type, reg;
2190 /* IE->LE transition:
2191 Originally it can be one of:
2192 movq foo@gottpoff(%rip), %reg
2193 addq foo@gottpoff(%rip), %reg
2194 We change it into:
2195 movq $foo, %reg
2196 leaq foo(%reg), %reg
2197 addq $foo, %reg. */
2198 BFD_ASSERT (rel->r_offset >= 3);
2199 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 3);
2200 BFD_ASSERT (val == 0x48 || val == 0x4c);
2201 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2202 BFD_ASSERT (type == 0x8b || type == 0x03);
2203 reg = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2204 BFD_ASSERT ((reg & 0xc7) == 5);
2205 reg >>= 3;
2206 BFD_ASSERT (rel->r_offset + 4 <= input_section->_raw_size);
2207 if (type == 0x8b)
2209 /* movq */
2210 if (val == 0x4c)
2211 bfd_put_8 (output_bfd, 0x49,
2212 contents + rel->r_offset - 3);
2213 bfd_put_8 (output_bfd, 0xc7,
2214 contents + rel->r_offset - 2);
2215 bfd_put_8 (output_bfd, 0xc0 | reg,
2216 contents + rel->r_offset - 1);
2218 else if (reg == 4)
2220 /* addq -> addq - addressing with %rsp/%r12 is
2221 special */
2222 if (val == 0x4c)
2223 bfd_put_8 (output_bfd, 0x49,
2224 contents + rel->r_offset - 3);
2225 bfd_put_8 (output_bfd, 0x81,
2226 contents + rel->r_offset - 2);
2227 bfd_put_8 (output_bfd, 0xc0 | reg,
2228 contents + rel->r_offset - 1);
2230 else
2232 /* addq -> leaq */
2233 if (val == 0x4c)
2234 bfd_put_8 (output_bfd, 0x4d,
2235 contents + rel->r_offset - 3);
2236 bfd_put_8 (output_bfd, 0x8d,
2237 contents + rel->r_offset - 2);
2238 bfd_put_8 (output_bfd, 0x80 | reg | (reg << 3),
2239 contents + rel->r_offset - 1);
2241 bfd_put_32 (output_bfd, tpoff (info, relocation),
2242 contents + rel->r_offset);
2243 continue;
2247 if (htab->sgot == NULL)
2248 abort ();
2250 if (h != NULL)
2251 off = h->got.offset;
2252 else
2254 if (local_got_offsets == NULL)
2255 abort ();
2257 off = local_got_offsets[r_symndx];
2260 if ((off & 1) != 0)
2261 off &= ~1;
2262 else
2264 Elf_Internal_Rela outrel;
2265 bfd_byte *loc;
2266 int dr_type, indx;
2268 if (htab->srelgot == NULL)
2269 abort ();
2271 outrel.r_offset = (htab->sgot->output_section->vma
2272 + htab->sgot->output_offset + off);
2274 indx = h && h->dynindx != -1 ? h->dynindx : 0;
2275 if (r_type == R_X86_64_TLSGD)
2276 dr_type = R_X86_64_DTPMOD64;
2277 else
2278 dr_type = R_X86_64_TPOFF64;
2280 bfd_put_64 (output_bfd, 0, htab->sgot->contents + off);
2281 outrel.r_addend = 0;
2282 if (dr_type == R_X86_64_TPOFF64 && indx == 0)
2283 outrel.r_addend = relocation - dtpoff_base (info);
2284 outrel.r_info = ELF64_R_INFO (indx, dr_type);
2286 loc = htab->srelgot->contents;
2287 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2288 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2290 if (r_type == R_X86_64_TLSGD)
2292 if (indx == 0)
2294 BFD_ASSERT (! unresolved_reloc);
2295 bfd_put_64 (output_bfd,
2296 relocation - dtpoff_base (info),
2297 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2299 else
2301 bfd_put_64 (output_bfd, 0,
2302 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2303 outrel.r_info = ELF64_R_INFO (indx,
2304 R_X86_64_DTPOFF64);
2305 outrel.r_offset += GOT_ENTRY_SIZE;
2306 htab->srelgot->reloc_count++;
2307 loc += sizeof (Elf64_External_Rela);
2308 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2312 if (h != NULL)
2313 h->got.offset |= 1;
2314 else
2315 local_got_offsets[r_symndx] |= 1;
2318 if (off >= (bfd_vma) -2)
2319 abort ();
2320 if (r_type == ELF64_R_TYPE (rel->r_info))
2322 relocation = htab->sgot->output_section->vma
2323 + htab->sgot->output_offset + off;
2324 unresolved_reloc = FALSE;
2326 else
2328 unsigned int i;
2329 static unsigned char tlsgd[8]
2330 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2332 /* GD->IE transition.
2333 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2334 .word 0x6666; rex64; call __tls_get_addr@plt
2335 Change it into:
2336 movq %fs:0, %rax
2337 addq foo@gottpoff(%rip), %rax */
2338 BFD_ASSERT (rel->r_offset >= 4);
2339 for (i = 0; i < 4; i++)
2340 BFD_ASSERT (bfd_get_8 (input_bfd,
2341 contents + rel->r_offset - 4 + i)
2342 == tlsgd[i]);
2343 BFD_ASSERT (rel->r_offset + 12 <= input_section->_raw_size);
2344 for (i = 0; i < 4; i++)
2345 BFD_ASSERT (bfd_get_8 (input_bfd,
2346 contents + rel->r_offset + 4 + i)
2347 == tlsgd[i+4]);
2348 BFD_ASSERT (rel + 1 < relend);
2349 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2350 memcpy (contents + rel->r_offset - 4,
2351 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0",
2352 16);
2354 relocation = (htab->sgot->output_section->vma
2355 + htab->sgot->output_offset + off
2356 - rel->r_offset
2357 - input_section->output_section->vma
2358 - input_section->output_offset
2359 - 12);
2360 bfd_put_32 (output_bfd, relocation,
2361 contents + rel->r_offset + 8);
2362 /* Skip R_X86_64_PLT32. */
2363 rel++;
2364 continue;
2366 break;
2368 case R_X86_64_TLSLD:
2369 if (! info->shared)
2371 /* LD->LE transition:
2372 Ensure it is:
2373 leaq foo@tlsld(%rip), %rdi; call __tls_get_addr@plt.
2374 We change it into:
2375 .word 0x6666; .byte 0x66; movl %fs:0, %rax. */
2376 BFD_ASSERT (rel->r_offset >= 3);
2377 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 3)
2378 == 0x48);
2379 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 2)
2380 == 0x8d);
2381 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 1)
2382 == 0x3d);
2383 BFD_ASSERT (rel->r_offset + 9 <= input_section->_raw_size);
2384 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2385 == 0xe8);
2386 BFD_ASSERT (rel + 1 < relend);
2387 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2388 memcpy (contents + rel->r_offset - 3,
2389 "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0", 12);
2390 /* Skip R_X86_64_PLT32. */
2391 rel++;
2392 continue;
2395 if (htab->sgot == NULL)
2396 abort ();
2398 off = htab->tls_ld_got.offset;
2399 if (off & 1)
2400 off &= ~1;
2401 else
2403 Elf_Internal_Rela outrel;
2404 bfd_byte *loc;
2406 if (htab->srelgot == NULL)
2407 abort ();
2409 outrel.r_offset = (htab->sgot->output_section->vma
2410 + htab->sgot->output_offset + off);
2412 bfd_put_64 (output_bfd, 0,
2413 htab->sgot->contents + off);
2414 bfd_put_64 (output_bfd, 0,
2415 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2416 outrel.r_info = ELF64_R_INFO (0, R_X86_64_DTPMOD64);
2417 outrel.r_addend = 0;
2418 loc = htab->srelgot->contents;
2419 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2420 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2421 htab->tls_ld_got.offset |= 1;
2423 relocation = htab->sgot->output_section->vma
2424 + htab->sgot->output_offset + off;
2425 unresolved_reloc = FALSE;
2426 break;
2428 case R_X86_64_DTPOFF32:
2429 if (info->shared || (input_section->flags & SEC_CODE) == 0)
2430 relocation -= dtpoff_base (info);
2431 else
2432 relocation = tpoff (info, relocation);
2433 break;
2435 case R_X86_64_TPOFF32:
2436 BFD_ASSERT (! info->shared);
2437 relocation = tpoff (info, relocation);
2438 break;
2440 default:
2441 break;
2444 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
2445 because such sections are not SEC_ALLOC and thus ld.so will
2446 not process them. */
2447 if (unresolved_reloc
2448 && !((input_section->flags & SEC_DEBUGGING) != 0
2449 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
2450 (*_bfd_error_handler)
2451 (_("%s(%s+0x%lx): unresolvable relocation against symbol `%s'"),
2452 bfd_archive_filename (input_bfd),
2453 bfd_get_section_name (input_bfd, input_section),
2454 (long) rel->r_offset,
2455 h->root.root.string);
2457 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
2458 contents, rel->r_offset,
2459 relocation, rel->r_addend);
2461 if (r != bfd_reloc_ok)
2463 const char *name;
2465 if (h != NULL)
2466 name = h->root.root.string;
2467 else
2469 name = bfd_elf_string_from_elf_section (input_bfd,
2470 symtab_hdr->sh_link,
2471 sym->st_name);
2472 if (name == NULL)
2473 return FALSE;
2474 if (*name == '\0')
2475 name = bfd_section_name (input_bfd, sec);
2478 if (r == bfd_reloc_overflow)
2481 if (! ((*info->callbacks->reloc_overflow)
2482 (info, name, howto->name, (bfd_vma) 0,
2483 input_bfd, input_section, rel->r_offset)))
2484 return FALSE;
2486 else
2488 (*_bfd_error_handler)
2489 (_("%s(%s+0x%lx): reloc against `%s': error %d"),
2490 bfd_archive_filename (input_bfd),
2491 bfd_get_section_name (input_bfd, input_section),
2492 (long) rel->r_offset, name, (int) r);
2493 return FALSE;
2498 return TRUE;
2501 /* Finish up dynamic symbol handling. We set the contents of various
2502 dynamic sections here. */
2504 static bfd_boolean
2505 elf64_x86_64_finish_dynamic_symbol (bfd *output_bfd,
2506 struct bfd_link_info *info,
2507 struct elf_link_hash_entry *h,
2508 Elf_Internal_Sym *sym)
2510 struct elf64_x86_64_link_hash_table *htab;
2512 htab = elf64_x86_64_hash_table (info);
2514 if (h->plt.offset != (bfd_vma) -1)
2516 bfd_vma plt_index;
2517 bfd_vma got_offset;
2518 Elf_Internal_Rela rela;
2519 bfd_byte *loc;
2521 /* This symbol has an entry in the procedure linkage table. Set
2522 it up. */
2523 if (h->dynindx == -1
2524 || htab->splt == NULL
2525 || htab->sgotplt == NULL
2526 || htab->srelplt == NULL)
2527 abort ();
2529 /* Get the index in the procedure linkage table which
2530 corresponds to this symbol. This is the index of this symbol
2531 in all the symbols for which we are making plt entries. The
2532 first entry in the procedure linkage table is reserved. */
2533 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2535 /* Get the offset into the .got table of the entry that
2536 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
2537 bytes. The first three are reserved for the dynamic linker. */
2538 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
2540 /* Fill in the entry in the procedure linkage table. */
2541 memcpy (htab->splt->contents + h->plt.offset, elf64_x86_64_plt_entry,
2542 PLT_ENTRY_SIZE);
2544 /* Insert the relocation positions of the plt section. The magic
2545 numbers at the end of the statements are the positions of the
2546 relocations in the plt section. */
2547 /* Put offset for jmp *name@GOTPCREL(%rip), since the
2548 instruction uses 6 bytes, subtract this value. */
2549 bfd_put_32 (output_bfd,
2550 (htab->sgotplt->output_section->vma
2551 + htab->sgotplt->output_offset
2552 + got_offset
2553 - htab->splt->output_section->vma
2554 - htab->splt->output_offset
2555 - h->plt.offset
2556 - 6),
2557 htab->splt->contents + h->plt.offset + 2);
2558 /* Put relocation index. */
2559 bfd_put_32 (output_bfd, plt_index,
2560 htab->splt->contents + h->plt.offset + 7);
2561 /* Put offset for jmp .PLT0. */
2562 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
2563 htab->splt->contents + h->plt.offset + 12);
2565 /* Fill in the entry in the global offset table, initially this
2566 points to the pushq instruction in the PLT which is at offset 6. */
2567 bfd_put_64 (output_bfd, (htab->splt->output_section->vma
2568 + htab->splt->output_offset
2569 + h->plt.offset + 6),
2570 htab->sgotplt->contents + got_offset);
2572 /* Fill in the entry in the .rela.plt section. */
2573 rela.r_offset = (htab->sgotplt->output_section->vma
2574 + htab->sgotplt->output_offset
2575 + got_offset);
2576 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
2577 rela.r_addend = 0;
2578 loc = htab->srelplt->contents + plt_index * sizeof (Elf64_External_Rela);
2579 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2581 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2583 /* Mark the symbol as undefined, rather than as defined in
2584 the .plt section. Leave the value alone. This is a clue
2585 for the dynamic linker, to make function pointer
2586 comparisons work between an application and shared
2587 library. */
2588 sym->st_shndx = SHN_UNDEF;
2592 if (h->got.offset != (bfd_vma) -1
2593 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_GD
2594 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE)
2596 Elf_Internal_Rela rela;
2597 bfd_byte *loc;
2599 /* This symbol has an entry in the global offset table. Set it
2600 up. */
2601 if (htab->sgot == NULL || htab->srelgot == NULL)
2602 abort ();
2604 rela.r_offset = (htab->sgot->output_section->vma
2605 + htab->sgot->output_offset
2606 + (h->got.offset &~ (bfd_vma) 1));
2608 /* If this is a static link, or it is a -Bsymbolic link and the
2609 symbol is defined locally or was forced to be local because
2610 of a version file, we just want to emit a RELATIVE reloc.
2611 The entry in the global offset table will already have been
2612 initialized in the relocate_section function. */
2613 if (info->shared
2614 && SYMBOL_REFERENCES_LOCAL (info, h))
2616 BFD_ASSERT((h->got.offset & 1) != 0);
2617 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2618 rela.r_addend = (h->root.u.def.value
2619 + h->root.u.def.section->output_section->vma
2620 + h->root.u.def.section->output_offset);
2622 else
2624 BFD_ASSERT((h->got.offset & 1) == 0);
2625 bfd_put_64 (output_bfd, (bfd_vma) 0,
2626 htab->sgot->contents + h->got.offset);
2627 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
2628 rela.r_addend = 0;
2631 loc = htab->srelgot->contents;
2632 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2633 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2636 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
2638 Elf_Internal_Rela rela;
2639 bfd_byte *loc;
2641 /* This symbol needs a copy reloc. Set it up. */
2643 if (h->dynindx == -1
2644 || (h->root.type != bfd_link_hash_defined
2645 && h->root.type != bfd_link_hash_defweak)
2646 || htab->srelbss == NULL)
2647 abort ();
2649 rela.r_offset = (h->root.u.def.value
2650 + h->root.u.def.section->output_section->vma
2651 + h->root.u.def.section->output_offset);
2652 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
2653 rela.r_addend = 0;
2654 loc = htab->srelbss->contents;
2655 loc += htab->srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
2656 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2659 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
2660 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
2661 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
2662 sym->st_shndx = SHN_ABS;
2664 return TRUE;
2667 /* Used to decide how to sort relocs in an optimal manner for the
2668 dynamic linker, before writing them out. */
2670 static enum elf_reloc_type_class
2671 elf64_x86_64_reloc_type_class (const Elf_Internal_Rela *rela)
2673 switch ((int) ELF64_R_TYPE (rela->r_info))
2675 case R_X86_64_RELATIVE:
2676 return reloc_class_relative;
2677 case R_X86_64_JUMP_SLOT:
2678 return reloc_class_plt;
2679 case R_X86_64_COPY:
2680 return reloc_class_copy;
2681 default:
2682 return reloc_class_normal;
2686 /* Finish up the dynamic sections. */
2688 static bfd_boolean
2689 elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
2691 struct elf64_x86_64_link_hash_table *htab;
2692 bfd *dynobj;
2693 asection *sdyn;
2695 htab = elf64_x86_64_hash_table (info);
2696 dynobj = htab->elf.dynobj;
2697 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2699 if (htab->elf.dynamic_sections_created)
2701 Elf64_External_Dyn *dyncon, *dynconend;
2703 if (sdyn == NULL || htab->sgot == NULL)
2704 abort ();
2706 dyncon = (Elf64_External_Dyn *) sdyn->contents;
2707 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
2708 for (; dyncon < dynconend; dyncon++)
2710 Elf_Internal_Dyn dyn;
2711 asection *s;
2713 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
2715 switch (dyn.d_tag)
2717 default:
2718 continue;
2720 case DT_PLTGOT:
2721 dyn.d_un.d_ptr = htab->sgot->output_section->vma;
2722 break;
2724 case DT_JMPREL:
2725 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
2726 break;
2728 case DT_PLTRELSZ:
2729 s = htab->srelplt->output_section;
2730 if (s->_cooked_size != 0)
2731 dyn.d_un.d_val = s->_cooked_size;
2732 else
2733 dyn.d_un.d_val = s->_raw_size;
2734 break;
2736 case DT_RELASZ:
2737 /* The procedure linkage table relocs (DT_JMPREL) should
2738 not be included in the overall relocs (DT_RELA).
2739 Therefore, we override the DT_RELASZ entry here to
2740 make it not include the JMPREL relocs. Since the
2741 linker script arranges for .rela.plt to follow all
2742 other relocation sections, we don't have to worry
2743 about changing the DT_RELA entry. */
2744 if (htab->srelplt != NULL)
2746 s = htab->srelplt->output_section;
2747 if (s->_cooked_size != 0)
2748 dyn.d_un.d_val -= s->_cooked_size;
2749 else
2750 dyn.d_un.d_val -= s->_raw_size;
2752 break;
2755 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
2758 /* Fill in the special first entry in the procedure linkage table. */
2759 if (htab->splt && htab->splt->_raw_size > 0)
2761 /* Fill in the first entry in the procedure linkage table. */
2762 memcpy (htab->splt->contents, elf64_x86_64_plt0_entry,
2763 PLT_ENTRY_SIZE);
2764 /* Add offset for pushq GOT+8(%rip), since the instruction
2765 uses 6 bytes subtract this value. */
2766 bfd_put_32 (output_bfd,
2767 (htab->sgotplt->output_section->vma
2768 + htab->sgotplt->output_offset
2770 - htab->splt->output_section->vma
2771 - htab->splt->output_offset
2772 - 6),
2773 htab->splt->contents + 2);
2774 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
2775 the end of the instruction. */
2776 bfd_put_32 (output_bfd,
2777 (htab->sgotplt->output_section->vma
2778 + htab->sgotplt->output_offset
2779 + 16
2780 - htab->splt->output_section->vma
2781 - htab->splt->output_offset
2782 - 12),
2783 htab->splt->contents + 8);
2785 elf_section_data (htab->splt->output_section)->this_hdr.sh_entsize =
2786 PLT_ENTRY_SIZE;
2790 if (htab->sgotplt)
2792 /* Fill in the first three entries in the global offset table. */
2793 if (htab->sgotplt->_raw_size > 0)
2795 /* Set the first entry in the global offset table to the address of
2796 the dynamic section. */
2797 if (sdyn == NULL)
2798 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents);
2799 else
2800 bfd_put_64 (output_bfd,
2801 sdyn->output_section->vma + sdyn->output_offset,
2802 htab->sgotplt->contents);
2803 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
2804 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE);
2805 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE*2);
2808 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize =
2809 GOT_ENTRY_SIZE;
2812 return TRUE;
2816 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
2817 #define TARGET_LITTLE_NAME "elf64-x86-64"
2818 #define ELF_ARCH bfd_arch_i386
2819 #define ELF_MACHINE_CODE EM_X86_64
2820 #define ELF_MAXPAGESIZE 0x100000
2822 #define elf_backend_can_gc_sections 1
2823 #define elf_backend_can_refcount 1
2824 #define elf_backend_want_got_plt 1
2825 #define elf_backend_plt_readonly 1
2826 #define elf_backend_want_plt_sym 0
2827 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
2828 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
2829 #define elf_backend_rela_normal 1
2831 #define elf_info_to_howto elf64_x86_64_info_to_howto
2833 #define bfd_elf64_bfd_link_hash_table_create \
2834 elf64_x86_64_link_hash_table_create
2835 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
2837 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
2838 #define elf_backend_check_relocs elf64_x86_64_check_relocs
2839 #define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol
2840 #define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections
2841 #define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections
2842 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
2843 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
2844 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
2845 #define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus
2846 #define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo
2847 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
2848 #define elf_backend_relocate_section elf64_x86_64_relocate_section
2849 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
2850 #define elf_backend_object_p elf64_x86_64_elf_object_p
2851 #define bfd_elf64_mkobject elf64_x86_64_mkobject
2853 #include "elf64-target.h"