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>.
6 This file is part of BFD, the Binary File Descriptor library.
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.
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.
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. */
28 #include "elf/x86-64.h"
30 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
31 #define MINUS_ONE (~ (bfd_vma) 0)
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[] =
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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,
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),
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),
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,
126 /* Map BFD relocs to the x86_64 elf relocs. */
129 bfd_reloc_code_real_type bfd_reloc_val;
130 unsigned char elf_reloc_val;
133 static const struct elf_reloc_map x86_64_reloc_map[] =
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, },
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)
174 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
177 if (x86_64_reloc_map[i].bfd_reloc_val == code)
178 return &x86_64_elf_howto_table[i];
183 /* Given an x86_64 ELF reloc type, fill in an arelent structure. */
186 elf64_x86_64_info_to_howto (bfd *abfd ATTRIBUTE_UNUSED, arelent *cache_ptr,
187 Elf_Internal_Rela *dst)
191 r_type = ELF64_R_TYPE (dst->r_info);
192 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT
193 || r_type >= (unsigned int) R_X86_64_max)
195 if (r_type > (unsigned int) R_X86_64_GOTPC32)
197 (*_bfd_error_handler) (_("%B: invalid relocation type %d"),
199 r_type = R_X86_64_NONE;
204 i = r_type - ((unsigned int) R_X86_64_GNU_VTINHERIT - R_X86_64_GOTPC32 - 1);
205 cache_ptr->howto = &x86_64_elf_howto_table[i];
206 BFD_ASSERT (r_type == cache_ptr->howto->type);
209 /* Support for core dump NOTE sections. */
211 elf64_x86_64_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
216 switch (note->descsz)
221 case 336: /* sizeof(istruct elf_prstatus) on Linux/x86_64 */
223 elf_tdata (abfd)->core_signal
224 = bfd_get_16 (abfd, note->descdata + 12);
227 elf_tdata (abfd)->core_pid
228 = bfd_get_32 (abfd, note->descdata + 32);
237 /* Make a ".reg/999" section. */
238 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
239 size, note->descpos + offset);
243 elf64_x86_64_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
245 switch (note->descsz)
250 case 136: /* sizeof(struct elf_prpsinfo) on Linux/x86_64 */
251 elf_tdata (abfd)->core_program
252 = _bfd_elfcore_strndup (abfd, note->descdata + 40, 16);
253 elf_tdata (abfd)->core_command
254 = _bfd_elfcore_strndup (abfd, note->descdata + 56, 80);
257 /* Note that for some reason, a spurious space is tacked
258 onto the end of the args in some (at least one anyway)
259 implementations, so strip it off if it exists. */
262 char *command = elf_tdata (abfd)->core_command;
263 int n = strlen (command);
265 if (0 < n && command[n - 1] == ' ')
266 command[n - 1] = '\0';
272 /* Functions for the x86-64 ELF linker. */
274 /* The name of the dynamic interpreter. This is put in the .interp
277 #define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
279 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
280 copying dynamic variables from a shared lib into an app's dynbss
281 section, and instead use a dynamic relocation to point into the
283 #define ELIMINATE_COPY_RELOCS 1
285 /* The size in bytes of an entry in the global offset table. */
287 #define GOT_ENTRY_SIZE 8
289 /* The size in bytes of an entry in the procedure linkage table. */
291 #define PLT_ENTRY_SIZE 16
293 /* The first entry in a procedure linkage table looks like this. See the
294 SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
296 static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
298 0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
299 0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
300 0x90, 0x90, 0x90, 0x90 /* pad out to 16 bytes with nops. */
303 /* Subsequent entries in a procedure linkage table look like this. */
305 static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
307 0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
308 0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
309 0x68, /* pushq immediate */
310 0, 0, 0, 0, /* replaced with index into relocation table. */
311 0xe9, /* jmp relative */
312 0, 0, 0, 0 /* replaced with offset to start of .plt0. */
315 /* The x86-64 linker needs to keep track of the number of relocs that
316 it decides to copy as dynamic relocs in check_relocs for each symbol.
317 This is so that it can later discard them if they are found to be
318 unnecessary. We store the information in a field extending the
319 regular ELF linker hash table. */
321 struct elf64_x86_64_dyn_relocs
324 struct elf64_x86_64_dyn_relocs *next;
326 /* The input section of the reloc. */
329 /* Total number of relocs copied for the input section. */
332 /* Number of pc-relative relocs copied for the input section. */
333 bfd_size_type pc_count;
336 /* x86-64 ELF linker hash entry. */
338 struct elf64_x86_64_link_hash_entry
340 struct elf_link_hash_entry elf;
342 /* Track dynamic relocs copied for this symbol. */
343 struct elf64_x86_64_dyn_relocs *dyn_relocs;
345 #define GOT_UNKNOWN 0
349 unsigned char tls_type;
352 #define elf64_x86_64_hash_entry(ent) \
353 ((struct elf64_x86_64_link_hash_entry *)(ent))
355 struct elf64_x86_64_obj_tdata
357 struct elf_obj_tdata root;
359 /* tls_type for each local got entry. */
360 char *local_got_tls_type;
363 #define elf64_x86_64_tdata(abfd) \
364 ((struct elf64_x86_64_obj_tdata *) (abfd)->tdata.any)
366 #define elf64_x86_64_local_got_tls_type(abfd) \
367 (elf64_x86_64_tdata (abfd)->local_got_tls_type)
370 /* x86-64 ELF linker hash table. */
372 struct elf64_x86_64_link_hash_table
374 struct elf_link_hash_table elf;
376 /* Short-cuts to get to dynamic linker sections. */
386 bfd_signed_vma refcount;
390 /* Small local sym to section mapping cache. */
391 struct sym_sec_cache sym_sec;
394 /* Get the x86-64 ELF linker hash table from a link_info structure. */
396 #define elf64_x86_64_hash_table(p) \
397 ((struct elf64_x86_64_link_hash_table *) ((p)->hash))
399 /* Create an entry in an x86-64 ELF linker hash table. */
401 static struct bfd_hash_entry *
402 link_hash_newfunc (struct bfd_hash_entry *entry, struct bfd_hash_table *table,
405 /* Allocate the structure if it has not already been allocated by a
409 entry = bfd_hash_allocate (table,
410 sizeof (struct elf64_x86_64_link_hash_entry));
415 /* Call the allocation method of the superclass. */
416 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
419 struct elf64_x86_64_link_hash_entry *eh;
421 eh = (struct elf64_x86_64_link_hash_entry *) entry;
422 eh->dyn_relocs = NULL;
423 eh->tls_type = GOT_UNKNOWN;
429 /* Create an X86-64 ELF linker hash table. */
431 static struct bfd_link_hash_table *
432 elf64_x86_64_link_hash_table_create (bfd *abfd)
434 struct elf64_x86_64_link_hash_table *ret;
435 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table);
437 ret = (struct elf64_x86_64_link_hash_table *) bfd_malloc (amt);
441 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc))
454 ret->sym_sec.abfd = NULL;
455 ret->tls_ld_got.refcount = 0;
457 return &ret->elf.root;
460 /* Create .got, .gotplt, and .rela.got sections in DYNOBJ, and set up
461 shortcuts to them in our hash table. */
464 create_got_section (bfd *dynobj, struct bfd_link_info *info)
466 struct elf64_x86_64_link_hash_table *htab;
468 if (! _bfd_elf_create_got_section (dynobj, info))
471 htab = elf64_x86_64_hash_table (info);
472 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
473 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
474 if (!htab->sgot || !htab->sgotplt)
477 htab->srelgot = bfd_make_section_with_flags (dynobj, ".rela.got",
478 (SEC_ALLOC | SEC_LOAD
483 if (htab->srelgot == NULL
484 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 3))
489 /* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and
490 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our
494 elf64_x86_64_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info)
496 struct elf64_x86_64_link_hash_table *htab;
498 htab = elf64_x86_64_hash_table (info);
499 if (!htab->sgot && !create_got_section (dynobj, info))
502 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
505 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
506 htab->srelplt = bfd_get_section_by_name (dynobj, ".rela.plt");
507 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
509 htab->srelbss = bfd_get_section_by_name (dynobj, ".rela.bss");
511 if (!htab->splt || !htab->srelplt || !htab->sdynbss
512 || (!info->shared && !htab->srelbss))
518 /* Copy the extra info we tack onto an elf_link_hash_entry. */
521 elf64_x86_64_copy_indirect_symbol (const struct elf_backend_data *bed,
522 struct elf_link_hash_entry *dir,
523 struct elf_link_hash_entry *ind)
525 struct elf64_x86_64_link_hash_entry *edir, *eind;
527 edir = (struct elf64_x86_64_link_hash_entry *) dir;
528 eind = (struct elf64_x86_64_link_hash_entry *) ind;
530 if (eind->dyn_relocs != NULL)
532 if (edir->dyn_relocs != NULL)
534 struct elf64_x86_64_dyn_relocs **pp;
535 struct elf64_x86_64_dyn_relocs *p;
537 if (ind->root.type == bfd_link_hash_indirect)
540 /* Add reloc counts against the weak sym to the strong sym
541 list. Merge any entries against the same section. */
542 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
544 struct elf64_x86_64_dyn_relocs *q;
546 for (q = edir->dyn_relocs; q != NULL; q = q->next)
547 if (q->sec == p->sec)
549 q->pc_count += p->pc_count;
550 q->count += p->count;
557 *pp = edir->dyn_relocs;
560 edir->dyn_relocs = eind->dyn_relocs;
561 eind->dyn_relocs = NULL;
564 if (ind->root.type == bfd_link_hash_indirect
565 && dir->got.refcount <= 0)
567 edir->tls_type = eind->tls_type;
568 eind->tls_type = GOT_UNKNOWN;
571 if (ELIMINATE_COPY_RELOCS
572 && ind->root.type != bfd_link_hash_indirect
573 && dir->dynamic_adjusted)
575 /* If called to transfer flags for a weakdef during processing
576 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
577 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
578 dir->ref_dynamic |= ind->ref_dynamic;
579 dir->ref_regular |= ind->ref_regular;
580 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
581 dir->needs_plt |= ind->needs_plt;
582 dir->pointer_equality_needed |= ind->pointer_equality_needed;
585 _bfd_elf_link_hash_copy_indirect (bed, dir, ind);
589 elf64_x86_64_mkobject (bfd *abfd)
591 bfd_size_type amt = sizeof (struct elf64_x86_64_obj_tdata);
592 abfd->tdata.any = bfd_zalloc (abfd, amt);
593 if (abfd->tdata.any == NULL)
599 elf64_x86_64_elf_object_p (bfd *abfd)
601 /* Set the right machine number for an x86-64 elf64 file. */
602 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
607 elf64_x86_64_tls_transition (struct bfd_link_info *info, int r_type, int is_local)
615 case R_X86_64_GOTTPOFF:
617 return R_X86_64_TPOFF32;
618 return R_X86_64_GOTTPOFF;
620 return R_X86_64_TPOFF32;
626 /* Look through the relocs for a section during the first phase, and
627 calculate needed space in the global offset table, procedure
628 linkage table, and dynamic reloc sections. */
631 elf64_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info, asection *sec,
632 const Elf_Internal_Rela *relocs)
634 struct elf64_x86_64_link_hash_table *htab;
635 Elf_Internal_Shdr *symtab_hdr;
636 struct elf_link_hash_entry **sym_hashes;
637 const Elf_Internal_Rela *rel;
638 const Elf_Internal_Rela *rel_end;
641 if (info->relocatable)
644 htab = elf64_x86_64_hash_table (info);
645 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
646 sym_hashes = elf_sym_hashes (abfd);
650 rel_end = relocs + sec->reloc_count;
651 for (rel = relocs; rel < rel_end; rel++)
654 unsigned long r_symndx;
655 struct elf_link_hash_entry *h;
657 r_symndx = ELF64_R_SYM (rel->r_info);
658 r_type = ELF64_R_TYPE (rel->r_info);
660 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
662 (*_bfd_error_handler) (_("%B: bad symbol index: %d"),
667 if (r_symndx < symtab_hdr->sh_info)
671 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
672 while (h->root.type == bfd_link_hash_indirect
673 || h->root.type == bfd_link_hash_warning)
674 h = (struct elf_link_hash_entry *) h->root.u.i.link;
677 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
681 htab->tls_ld_got.refcount += 1;
684 case R_X86_64_TPOFF32:
687 (*_bfd_error_handler)
688 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
690 x86_64_elf_howto_table[r_type].name,
691 (h) ? h->root.root.string : "a local symbol");
692 bfd_set_error (bfd_error_bad_value);
697 case R_X86_64_GOTTPOFF:
699 info->flags |= DF_STATIC_TLS;
703 case R_X86_64_GOTPCREL:
705 /* This symbol requires a global offset table entry. */
707 int tls_type, old_tls_type;
711 default: tls_type = GOT_NORMAL; break;
712 case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
713 case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
718 h->got.refcount += 1;
719 old_tls_type = elf64_x86_64_hash_entry (h)->tls_type;
723 bfd_signed_vma *local_got_refcounts;
725 /* This is a global offset table entry for a local symbol. */
726 local_got_refcounts = elf_local_got_refcounts (abfd);
727 if (local_got_refcounts == NULL)
731 size = symtab_hdr->sh_info;
732 size *= sizeof (bfd_signed_vma) + sizeof (char);
733 local_got_refcounts = ((bfd_signed_vma *)
734 bfd_zalloc (abfd, size));
735 if (local_got_refcounts == NULL)
737 elf_local_got_refcounts (abfd) = local_got_refcounts;
738 elf64_x86_64_local_got_tls_type (abfd)
739 = (char *) (local_got_refcounts + symtab_hdr->sh_info);
741 local_got_refcounts[r_symndx] += 1;
743 = elf64_x86_64_local_got_tls_type (abfd) [r_symndx];
746 /* If a TLS symbol is accessed using IE at least once,
747 there is no point to use dynamic model for it. */
748 if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
749 && (old_tls_type != GOT_TLS_GD || tls_type != GOT_TLS_IE))
751 if (old_tls_type == GOT_TLS_IE && tls_type == GOT_TLS_GD)
752 tls_type = old_tls_type;
755 (*_bfd_error_handler)
756 (_("%B: %s' accessed both as normal and thread local symbol"),
757 abfd, h ? h->root.root.string : "<local>");
762 if (old_tls_type != tls_type)
765 elf64_x86_64_hash_entry (h)->tls_type = tls_type;
767 elf64_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
772 case R_X86_64_GOTOFF64:
773 case R_X86_64_GOTPC32:
775 if (htab->sgot == NULL)
777 if (htab->elf.dynobj == NULL)
778 htab->elf.dynobj = abfd;
779 if (!create_got_section (htab->elf.dynobj, info))
785 /* This symbol requires a procedure linkage table entry. We
786 actually build the entry in adjust_dynamic_symbol,
787 because this might be a case of linking PIC code which is
788 never referenced by a dynamic object, in which case we
789 don't need to generate a procedure linkage table entry
792 /* If this is a local symbol, we resolve it directly without
793 creating a procedure linkage table entry. */
798 h->plt.refcount += 1;
805 /* Let's help debug shared library creation. These relocs
806 cannot be used in shared libs. Don't error out for
807 sections we don't care about, such as debug sections or
808 non-constant sections. */
810 && (sec->flags & SEC_ALLOC) != 0
811 && (sec->flags & SEC_READONLY) != 0)
813 (*_bfd_error_handler)
814 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
816 x86_64_elf_howto_table[r_type].name,
817 (h) ? h->root.root.string : "a local symbol");
818 bfd_set_error (bfd_error_bad_value);
828 if (h != NULL && !info->shared)
830 /* If this reloc is in a read-only section, we might
831 need a copy reloc. We can't check reliably at this
832 stage whether the section is read-only, as input
833 sections have not yet been mapped to output sections.
834 Tentatively set the flag for now, and correct in
835 adjust_dynamic_symbol. */
838 /* We may need a .plt entry if the function this reloc
839 refers to is in a shared lib. */
840 h->plt.refcount += 1;
841 if (r_type != R_X86_64_PC32 && r_type != R_X86_64_PC64)
842 h->pointer_equality_needed = 1;
845 /* If we are creating a shared library, and this is a reloc
846 against a global symbol, or a non PC relative reloc
847 against a local symbol, then we need to copy the reloc
848 into the shared library. However, if we are linking with
849 -Bsymbolic, we do not need to copy a reloc against a
850 global symbol which is defined in an object we are
851 including in the link (i.e., DEF_REGULAR is set). At
852 this point we have not seen all the input files, so it is
853 possible that DEF_REGULAR is not set now but will be set
854 later (it is never cleared). In case of a weak definition,
855 DEF_REGULAR may be cleared later by a strong definition in
856 a shared library. We account for that possibility below by
857 storing information in the relocs_copied field of the hash
858 table entry. A similar situation occurs when creating
859 shared libraries and symbol visibility changes render the
862 If on the other hand, we are creating an executable, we
863 may need to keep relocations for symbols satisfied by a
864 dynamic library if we manage to avoid copy relocs for the
867 && (sec->flags & SEC_ALLOC) != 0
868 && (((r_type != R_X86_64_PC8)
869 && (r_type != R_X86_64_PC16)
870 && (r_type != R_X86_64_PC32)
871 && (r_type != R_X86_64_PC64))
874 || h->root.type == bfd_link_hash_defweak
875 || !h->def_regular))))
876 || (ELIMINATE_COPY_RELOCS
878 && (sec->flags & SEC_ALLOC) != 0
880 && (h->root.type == bfd_link_hash_defweak
881 || !h->def_regular)))
883 struct elf64_x86_64_dyn_relocs *p;
884 struct elf64_x86_64_dyn_relocs **head;
886 /* We must copy these reloc types into the output file.
887 Create a reloc section in dynobj and make room for
894 name = (bfd_elf_string_from_elf_section
896 elf_elfheader (abfd)->e_shstrndx,
897 elf_section_data (sec)->rel_hdr.sh_name));
901 if (strncmp (name, ".rela", 5) != 0
902 || strcmp (bfd_get_section_name (abfd, sec),
905 (*_bfd_error_handler)
906 (_("%B: bad relocation section name `%s\'"),
910 if (htab->elf.dynobj == NULL)
911 htab->elf.dynobj = abfd;
913 dynobj = htab->elf.dynobj;
915 sreloc = bfd_get_section_by_name (dynobj, name);
920 flags = (SEC_HAS_CONTENTS | SEC_READONLY
921 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
922 if ((sec->flags & SEC_ALLOC) != 0)
923 flags |= SEC_ALLOC | SEC_LOAD;
924 sreloc = bfd_make_section_with_flags (dynobj,
928 || ! bfd_set_section_alignment (dynobj, sreloc, 3))
931 elf_section_data (sec)->sreloc = sreloc;
934 /* If this is a global symbol, we count the number of
935 relocations we need for this symbol. */
938 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs;
942 /* Track dynamic relocs needed for local syms too.
943 We really need local syms available to do this
947 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
952 head = ((struct elf64_x86_64_dyn_relocs **)
953 &elf_section_data (s)->local_dynrel);
957 if (p == NULL || p->sec != sec)
959 bfd_size_type amt = sizeof *p;
960 p = ((struct elf64_x86_64_dyn_relocs *)
961 bfd_alloc (htab->elf.dynobj, amt));
972 if (r_type == R_X86_64_PC8
973 || r_type == R_X86_64_PC16
974 || r_type == R_X86_64_PC32
975 || r_type == R_X86_64_PC64)
980 /* This relocation describes the C++ object vtable hierarchy.
981 Reconstruct it for later use during GC. */
982 case R_X86_64_GNU_VTINHERIT:
983 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
987 /* This relocation describes which C++ vtable entries are actually
988 used. Record for later use during GC. */
989 case R_X86_64_GNU_VTENTRY:
990 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
1002 /* Return the section that should be marked against GC for a given
1006 elf64_x86_64_gc_mark_hook (asection *sec,
1007 struct bfd_link_info *info ATTRIBUTE_UNUSED,
1008 Elf_Internal_Rela *rel,
1009 struct elf_link_hash_entry *h,
1010 Elf_Internal_Sym *sym)
1014 switch (ELF64_R_TYPE (rel->r_info))
1016 case R_X86_64_GNU_VTINHERIT:
1017 case R_X86_64_GNU_VTENTRY:
1021 switch (h->root.type)
1023 case bfd_link_hash_defined:
1024 case bfd_link_hash_defweak:
1025 return h->root.u.def.section;
1027 case bfd_link_hash_common:
1028 return h->root.u.c.p->section;
1036 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
1041 /* Update the got entry reference counts for the section being removed. */
1044 elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
1045 asection *sec, const Elf_Internal_Rela *relocs)
1047 Elf_Internal_Shdr *symtab_hdr;
1048 struct elf_link_hash_entry **sym_hashes;
1049 bfd_signed_vma *local_got_refcounts;
1050 const Elf_Internal_Rela *rel, *relend;
1052 elf_section_data (sec)->local_dynrel = NULL;
1054 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1055 sym_hashes = elf_sym_hashes (abfd);
1056 local_got_refcounts = elf_local_got_refcounts (abfd);
1058 relend = relocs + sec->reloc_count;
1059 for (rel = relocs; rel < relend; rel++)
1061 unsigned long r_symndx;
1062 unsigned int r_type;
1063 struct elf_link_hash_entry *h = NULL;
1065 r_symndx = ELF64_R_SYM (rel->r_info);
1066 if (r_symndx >= symtab_hdr->sh_info)
1068 struct elf64_x86_64_link_hash_entry *eh;
1069 struct elf64_x86_64_dyn_relocs **pp;
1070 struct elf64_x86_64_dyn_relocs *p;
1072 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1073 while (h->root.type == bfd_link_hash_indirect
1074 || h->root.type == bfd_link_hash_warning)
1075 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1076 eh = (struct elf64_x86_64_link_hash_entry *) h;
1078 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1081 /* Everything must go for SEC. */
1087 r_type = ELF64_R_TYPE (rel->r_info);
1088 r_type = elf64_x86_64_tls_transition (info, r_type, h != NULL);
1091 case R_X86_64_TLSLD:
1092 if (elf64_x86_64_hash_table (info)->tls_ld_got.refcount > 0)
1093 elf64_x86_64_hash_table (info)->tls_ld_got.refcount -= 1;
1096 case R_X86_64_TLSGD:
1097 case R_X86_64_GOTTPOFF:
1098 case R_X86_64_GOT32:
1099 case R_X86_64_GOTPCREL:
1102 if (h->got.refcount > 0)
1103 h->got.refcount -= 1;
1105 else if (local_got_refcounts != NULL)
1107 if (local_got_refcounts[r_symndx] > 0)
1108 local_got_refcounts[r_symndx] -= 1;
1125 case R_X86_64_PLT32:
1128 if (h->plt.refcount > 0)
1129 h->plt.refcount -= 1;
1141 /* Adjust a symbol defined by a dynamic object and referenced by a
1142 regular object. The current definition is in some section of the
1143 dynamic object, but we're not including those sections. We have to
1144 change the definition to something the rest of the link can
1148 elf64_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
1149 struct elf_link_hash_entry *h)
1151 struct elf64_x86_64_link_hash_table *htab;
1153 unsigned int power_of_two;
1155 /* If this is a function, put it in the procedure linkage table. We
1156 will fill in the contents of the procedure linkage table later,
1157 when we know the address of the .got section. */
1158 if (h->type == STT_FUNC
1161 if (h->plt.refcount <= 0
1162 || SYMBOL_CALLS_LOCAL (info, h)
1163 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1164 && h->root.type == bfd_link_hash_undefweak))
1166 /* This case can occur if we saw a PLT32 reloc in an input
1167 file, but the symbol was never referred to by a dynamic
1168 object, or if all references were garbage collected. In
1169 such a case, we don't actually need to build a procedure
1170 linkage table, and we can just do a PC32 reloc instead. */
1171 h->plt.offset = (bfd_vma) -1;
1178 /* It's possible that we incorrectly decided a .plt reloc was
1179 needed for an R_X86_64_PC32 reloc to a non-function sym in
1180 check_relocs. We can't decide accurately between function and
1181 non-function syms in check-relocs; Objects loaded later in
1182 the link may change h->type. So fix it now. */
1183 h->plt.offset = (bfd_vma) -1;
1185 /* If this is a weak symbol, and there is a real definition, the
1186 processor independent code will have arranged for us to see the
1187 real definition first, and we can just use the same value. */
1188 if (h->u.weakdef != NULL)
1190 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1191 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1192 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1193 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1194 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1195 h->non_got_ref = h->u.weakdef->non_got_ref;
1199 /* This is a reference to a symbol defined by a dynamic object which
1200 is not a function. */
1202 /* If we are creating a shared library, we must presume that the
1203 only references to the symbol are via the global offset table.
1204 For such cases we need not do anything here; the relocations will
1205 be handled correctly by relocate_section. */
1209 /* If there are no references to this symbol that do not use the
1210 GOT, we don't need to generate a copy reloc. */
1211 if (!h->non_got_ref)
1214 /* If -z nocopyreloc was given, we won't generate them either. */
1215 if (info->nocopyreloc)
1221 if (ELIMINATE_COPY_RELOCS)
1223 struct elf64_x86_64_link_hash_entry * eh;
1224 struct elf64_x86_64_dyn_relocs *p;
1226 eh = (struct elf64_x86_64_link_hash_entry *) h;
1227 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1229 s = p->sec->output_section;
1230 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1234 /* If we didn't find any dynamic relocs in read-only sections, then
1235 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1243 /* We must allocate the symbol in our .dynbss section, which will
1244 become part of the .bss section of the executable. There will be
1245 an entry for this symbol in the .dynsym section. The dynamic
1246 object will contain position independent code, so all references
1247 from the dynamic object to this symbol will go through the global
1248 offset table. The dynamic linker will use the .dynsym entry to
1249 determine the address it must put in the global offset table, so
1250 both the dynamic object and the regular object will refer to the
1251 same memory location for the variable. */
1253 htab = elf64_x86_64_hash_table (info);
1255 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
1256 to copy the initial value out of the dynamic object and into the
1257 runtime process image. */
1258 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1260 htab->srelbss->size += sizeof (Elf64_External_Rela);
1264 /* We need to figure out the alignment required for this symbol. I
1265 have no idea how ELF linkers handle this. 16-bytes is the size
1266 of the largest type that requires hard alignment -- long double. */
1267 /* FIXME: This is VERY ugly. Should be fixed for all architectures using
1269 power_of_two = bfd_log2 (h->size);
1270 if (power_of_two > 4)
1273 /* Apply the required alignment. */
1275 s->size = BFD_ALIGN (s->size, (bfd_size_type) (1 << power_of_two));
1276 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1278 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1282 /* Define the symbol as being at this point in the section. */
1283 h->root.u.def.section = s;
1284 h->root.u.def.value = s->size;
1286 /* Increment the section size to make room for the symbol. */
1292 /* Allocate space in .plt, .got and associated reloc sections for
1296 allocate_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1298 struct bfd_link_info *info;
1299 struct elf64_x86_64_link_hash_table *htab;
1300 struct elf64_x86_64_link_hash_entry *eh;
1301 struct elf64_x86_64_dyn_relocs *p;
1303 if (h->root.type == bfd_link_hash_indirect)
1306 if (h->root.type == bfd_link_hash_warning)
1307 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1309 info = (struct bfd_link_info *) inf;
1310 htab = elf64_x86_64_hash_table (info);
1312 if (htab->elf.dynamic_sections_created
1313 && h->plt.refcount > 0)
1315 /* Make sure this symbol is output as a dynamic symbol.
1316 Undefined weak syms won't yet be marked as dynamic. */
1317 if (h->dynindx == -1
1318 && !h->forced_local)
1320 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1325 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
1327 asection *s = htab->splt;
1329 /* If this is the first .plt entry, make room for the special
1332 s->size += PLT_ENTRY_SIZE;
1334 h->plt.offset = s->size;
1336 /* If this symbol is not defined in a regular file, and we are
1337 not generating a shared library, then set the symbol to this
1338 location in the .plt. This is required to make function
1339 pointers compare as equal between the normal executable and
1340 the shared library. */
1344 h->root.u.def.section = s;
1345 h->root.u.def.value = h->plt.offset;
1348 /* Make room for this entry. */
1349 s->size += PLT_ENTRY_SIZE;
1351 /* We also need to make an entry in the .got.plt section, which
1352 will be placed in the .got section by the linker script. */
1353 htab->sgotplt->size += GOT_ENTRY_SIZE;
1355 /* We also need to make an entry in the .rela.plt section. */
1356 htab->srelplt->size += sizeof (Elf64_External_Rela);
1360 h->plt.offset = (bfd_vma) -1;
1366 h->plt.offset = (bfd_vma) -1;
1370 /* If R_X86_64_GOTTPOFF symbol is now local to the binary,
1371 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
1372 if (h->got.refcount > 0
1375 && elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
1376 h->got.offset = (bfd_vma) -1;
1377 else if (h->got.refcount > 0)
1381 int tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1383 /* Make sure this symbol is output as a dynamic symbol.
1384 Undefined weak syms won't yet be marked as dynamic. */
1385 if (h->dynindx == -1
1386 && !h->forced_local)
1388 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1393 h->got.offset = s->size;
1394 s->size += GOT_ENTRY_SIZE;
1395 /* R_X86_64_TLSGD needs 2 consecutive GOT slots. */
1396 if (tls_type == GOT_TLS_GD)
1397 s->size += GOT_ENTRY_SIZE;
1398 dyn = htab->elf.dynamic_sections_created;
1399 /* R_X86_64_TLSGD needs one dynamic relocation if local symbol
1401 R_X86_64_GOTTPOFF needs one dynamic relocation. */
1402 if ((tls_type == GOT_TLS_GD && h->dynindx == -1)
1403 || tls_type == GOT_TLS_IE)
1404 htab->srelgot->size += sizeof (Elf64_External_Rela);
1405 else if (tls_type == GOT_TLS_GD)
1406 htab->srelgot->size += 2 * sizeof (Elf64_External_Rela);
1407 else if ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1408 || h->root.type != bfd_link_hash_undefweak)
1410 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
1411 htab->srelgot->size += sizeof (Elf64_External_Rela);
1414 h->got.offset = (bfd_vma) -1;
1416 eh = (struct elf64_x86_64_link_hash_entry *) h;
1417 if (eh->dyn_relocs == NULL)
1420 /* In the shared -Bsymbolic case, discard space allocated for
1421 dynamic pc-relative relocs against symbols which turn out to be
1422 defined in regular objects. For the normal shared case, discard
1423 space for pc-relative relocs that have become local due to symbol
1424 visibility changes. */
1428 /* Relocs that use pc_count are those that appear on a call
1429 insn, or certain REL relocs that can generated via assembly.
1430 We want calls to protected symbols to resolve directly to the
1431 function rather than going via the plt. If people want
1432 function pointer comparisons to work as expected then they
1433 should avoid writing weird assembly. */
1434 if (SYMBOL_CALLS_LOCAL (info, h))
1436 struct elf64_x86_64_dyn_relocs **pp;
1438 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1440 p->count -= p->pc_count;
1449 /* Also discard relocs on undefined weak syms with non-default
1451 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1452 && h->root.type == bfd_link_hash_undefweak)
1453 eh->dyn_relocs = NULL;
1455 else if (ELIMINATE_COPY_RELOCS)
1457 /* For the non-shared case, discard space for relocs against
1458 symbols which turn out to need copy relocs or are not
1464 || (htab->elf.dynamic_sections_created
1465 && (h->root.type == bfd_link_hash_undefweak
1466 || h->root.type == bfd_link_hash_undefined))))
1468 /* Make sure this symbol is output as a dynamic symbol.
1469 Undefined weak syms won't yet be marked as dynamic. */
1470 if (h->dynindx == -1
1471 && !h->forced_local)
1473 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1477 /* If that succeeded, we know we'll be keeping all the
1479 if (h->dynindx != -1)
1483 eh->dyn_relocs = NULL;
1488 /* Finally, allocate space. */
1489 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1491 asection *sreloc = elf_section_data (p->sec)->sreloc;
1492 sreloc->size += p->count * sizeof (Elf64_External_Rela);
1498 /* Find any dynamic relocs that apply to read-only sections. */
1501 readonly_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1503 struct elf64_x86_64_link_hash_entry *eh;
1504 struct elf64_x86_64_dyn_relocs *p;
1506 if (h->root.type == bfd_link_hash_warning)
1507 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1509 eh = (struct elf64_x86_64_link_hash_entry *) h;
1510 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1512 asection *s = p->sec->output_section;
1514 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1516 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1518 info->flags |= DF_TEXTREL;
1520 /* Not an error, just cut short the traversal. */
1527 /* Set the sizes of the dynamic sections. */
1530 elf64_x86_64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
1531 struct bfd_link_info *info)
1533 struct elf64_x86_64_link_hash_table *htab;
1539 htab = elf64_x86_64_hash_table (info);
1540 dynobj = htab->elf.dynobj;
1544 if (htab->elf.dynamic_sections_created)
1546 /* Set the contents of the .interp section to the interpreter. */
1547 if (info->executable)
1549 s = bfd_get_section_by_name (dynobj, ".interp");
1552 s->size = sizeof ELF_DYNAMIC_INTERPRETER;
1553 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1557 /* Set up .got offsets for local syms, and space for local dynamic
1559 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1561 bfd_signed_vma *local_got;
1562 bfd_signed_vma *end_local_got;
1563 char *local_tls_type;
1564 bfd_size_type locsymcount;
1565 Elf_Internal_Shdr *symtab_hdr;
1568 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1571 for (s = ibfd->sections; s != NULL; s = s->next)
1573 struct elf64_x86_64_dyn_relocs *p;
1575 for (p = *((struct elf64_x86_64_dyn_relocs **)
1576 &elf_section_data (s)->local_dynrel);
1580 if (!bfd_is_abs_section (p->sec)
1581 && bfd_is_abs_section (p->sec->output_section))
1583 /* Input section has been discarded, either because
1584 it is a copy of a linkonce section or due to
1585 linker script /DISCARD/, so we'll be discarding
1588 else if (p->count != 0)
1590 srel = elf_section_data (p->sec)->sreloc;
1591 srel->size += p->count * sizeof (Elf64_External_Rela);
1592 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1593 info->flags |= DF_TEXTREL;
1599 local_got = elf_local_got_refcounts (ibfd);
1603 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1604 locsymcount = symtab_hdr->sh_info;
1605 end_local_got = local_got + locsymcount;
1606 local_tls_type = elf64_x86_64_local_got_tls_type (ibfd);
1608 srel = htab->srelgot;
1609 for (; local_got < end_local_got; ++local_got, ++local_tls_type)
1613 *local_got = s->size;
1614 s->size += GOT_ENTRY_SIZE;
1615 if (*local_tls_type == GOT_TLS_GD)
1616 s->size += GOT_ENTRY_SIZE;
1618 || *local_tls_type == GOT_TLS_GD
1619 || *local_tls_type == GOT_TLS_IE)
1620 srel->size += sizeof (Elf64_External_Rela);
1623 *local_got = (bfd_vma) -1;
1627 if (htab->tls_ld_got.refcount > 0)
1629 /* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD
1631 htab->tls_ld_got.offset = htab->sgot->size;
1632 htab->sgot->size += 2 * GOT_ENTRY_SIZE;
1633 htab->srelgot->size += sizeof (Elf64_External_Rela);
1636 htab->tls_ld_got.offset = -1;
1638 /* Allocate global sym .plt and .got entries, and space for global
1639 sym dynamic relocs. */
1640 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1642 /* We now have determined the sizes of the various dynamic sections.
1643 Allocate memory for them. */
1645 for (s = dynobj->sections; s != NULL; s = s->next)
1647 if ((s->flags & SEC_LINKER_CREATED) == 0)
1652 || s == htab->sgotplt
1653 || s == htab->sdynbss)
1655 /* Strip this section if we don't need it; see the
1658 else if (strncmp (bfd_get_section_name (dynobj, s), ".rela", 5) == 0)
1660 if (s->size != 0 && s != htab->srelplt)
1663 /* We use the reloc_count field as a counter if we need
1664 to copy relocs into the output file. */
1669 /* It's not one of our sections, so don't allocate space. */
1675 /* If we don't need this section, strip it from the
1676 output file. This is mostly to handle .rela.bss and
1677 .rela.plt. We must create both sections in
1678 create_dynamic_sections, because they must be created
1679 before the linker maps input sections to output
1680 sections. The linker does that before
1681 adjust_dynamic_symbol is called, and it is that
1682 function which decides whether anything needs to go
1683 into these sections. */
1685 s->flags |= SEC_EXCLUDE;
1689 if ((s->flags & SEC_HAS_CONTENTS) == 0)
1692 /* Allocate memory for the section contents. We use bfd_zalloc
1693 here in case unused entries are not reclaimed before the
1694 section's contents are written out. This should not happen,
1695 but this way if it does, we get a R_X86_64_NONE reloc instead
1697 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->size);
1698 if (s->contents == NULL)
1702 if (htab->elf.dynamic_sections_created)
1704 /* Add some entries to the .dynamic section. We fill in the
1705 values later, in elf64_x86_64_finish_dynamic_sections, but we
1706 must add the entries now so that we get the correct size for
1707 the .dynamic section. The DT_DEBUG entry is filled in by the
1708 dynamic linker and used by the debugger. */
1709 #define add_dynamic_entry(TAG, VAL) \
1710 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1712 if (info->executable)
1714 if (!add_dynamic_entry (DT_DEBUG, 0))
1718 if (htab->splt->size != 0)
1720 if (!add_dynamic_entry (DT_PLTGOT, 0)
1721 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1722 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1723 || !add_dynamic_entry (DT_JMPREL, 0))
1729 if (!add_dynamic_entry (DT_RELA, 0)
1730 || !add_dynamic_entry (DT_RELASZ, 0)
1731 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
1734 /* If any dynamic relocs apply to a read-only section,
1735 then we need a DT_TEXTREL entry. */
1736 if ((info->flags & DF_TEXTREL) == 0)
1737 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
1740 if ((info->flags & DF_TEXTREL) != 0)
1742 if (!add_dynamic_entry (DT_TEXTREL, 0))
1747 #undef add_dynamic_entry
1752 /* Return the base VMA address which should be subtracted from real addresses
1753 when resolving @dtpoff relocation.
1754 This is PT_TLS segment p_vaddr. */
1757 dtpoff_base (struct bfd_link_info *info)
1759 /* If tls_sec is NULL, we should have signalled an error already. */
1760 if (elf_hash_table (info)->tls_sec == NULL)
1762 return elf_hash_table (info)->tls_sec->vma;
1765 /* Return the relocation value for @tpoff relocation
1766 if STT_TLS virtual address is ADDRESS. */
1769 tpoff (struct bfd_link_info *info, bfd_vma address)
1771 struct elf_link_hash_table *htab = elf_hash_table (info);
1773 /* If tls_segment is NULL, we should have signalled an error already. */
1774 if (htab->tls_sec == NULL)
1776 return address - htab->tls_size - htab->tls_sec->vma;
1779 /* Is the instruction before OFFSET in CONTENTS a 32bit relative
1783 is_32bit_relative_branch (bfd_byte *contents, bfd_vma offset)
1785 /* Opcode Instruction
1788 0x0f 0x8x conditional jump */
1790 && (contents [offset - 1] == 0xe8
1791 || contents [offset - 1] == 0xe9))
1793 && contents [offset - 2] == 0x0f
1794 && (contents [offset - 1] & 0xf0) == 0x80));
1797 /* Relocate an x86_64 ELF section. */
1800 elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
1801 bfd *input_bfd, asection *input_section,
1802 bfd_byte *contents, Elf_Internal_Rela *relocs,
1803 Elf_Internal_Sym *local_syms,
1804 asection **local_sections)
1806 struct elf64_x86_64_link_hash_table *htab;
1807 Elf_Internal_Shdr *symtab_hdr;
1808 struct elf_link_hash_entry **sym_hashes;
1809 bfd_vma *local_got_offsets;
1810 Elf_Internal_Rela *rel;
1811 Elf_Internal_Rela *relend;
1813 if (info->relocatable)
1816 htab = elf64_x86_64_hash_table (info);
1817 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1818 sym_hashes = elf_sym_hashes (input_bfd);
1819 local_got_offsets = elf_local_got_offsets (input_bfd);
1822 relend = relocs + input_section->reloc_count;
1823 for (; rel < relend; rel++)
1825 unsigned int r_type;
1826 reloc_howto_type *howto;
1827 unsigned long r_symndx;
1828 struct elf_link_hash_entry *h;
1829 Elf_Internal_Sym *sym;
1833 bfd_boolean unresolved_reloc;
1834 bfd_reloc_status_type r;
1837 r_type = ELF64_R_TYPE (rel->r_info);
1838 if (r_type == (int) R_X86_64_GNU_VTINHERIT
1839 || r_type == (int) R_X86_64_GNU_VTENTRY)
1842 if (r_type >= R_X86_64_max)
1844 bfd_set_error (bfd_error_bad_value);
1848 howto = x86_64_elf_howto_table + r_type;
1849 r_symndx = ELF64_R_SYM (rel->r_info);
1853 unresolved_reloc = FALSE;
1854 if (r_symndx < symtab_hdr->sh_info)
1856 sym = local_syms + r_symndx;
1857 sec = local_sections[r_symndx];
1859 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
1865 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
1866 r_symndx, symtab_hdr, sym_hashes,
1868 unresolved_reloc, warned);
1870 /* When generating a shared object, the relocations handled here are
1871 copied into the output file to be resolved at run time. */
1874 case R_X86_64_GOT32:
1875 /* Relocation is to the entry for this symbol in the global
1877 case R_X86_64_GOTPCREL:
1878 /* Use global offset table as symbol value. */
1879 if (htab->sgot == NULL)
1886 off = h->got.offset;
1887 dyn = htab->elf.dynamic_sections_created;
1889 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
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. */
1910 bfd_put_64 (output_bfd, relocation,
1911 htab->sgot->contents + off);
1916 unresolved_reloc = FALSE;
1920 if (local_got_offsets == NULL)
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. */
1932 bfd_put_64 (output_bfd, relocation,
1933 htab->sgot->contents + off);
1938 Elf_Internal_Rela outrel;
1941 /* We need to generate a R_X86_64_RELATIVE reloc
1942 for the dynamic linker. */
1947 outrel.r_offset = (htab->sgot->output_section->vma
1948 + htab->sgot->output_offset
1950 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
1951 outrel.r_addend = relocation;
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)
1964 relocation = htab->sgot->output_section->vma
1965 + htab->sgot->output_offset + off;
1966 if (r_type != R_X86_64_GOTPCREL)
1967 relocation -= htab->sgotplt->output_section->vma
1968 - htab->sgotplt->output_offset;
1972 case R_X86_64_GOTOFF64:
1973 /* Relocation is relative to the start of the global offset
1976 /* Check to make sure it isn't a protected function symbol
1977 for shared library since it may not be local when used
1978 as function address. */
1982 && h->type == STT_FUNC
1983 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
1985 (*_bfd_error_handler)
1986 (_("%B: relocation R_X86_64_GOTOFF64 against protected function `%s' can not be used when making a shared object"),
1987 input_bfd, h->root.root.string);
1988 bfd_set_error (bfd_error_bad_value);
1992 /* Note that sgot is not involved in this
1993 calculation. We always want the start of .got.plt. If we
1994 defined _GLOBAL_OFFSET_TABLE_ in a different way, as is
1995 permitted by the ABI, we might have to change this
1997 relocation -= htab->sgotplt->output_section->vma
1998 + htab->sgotplt->output_offset;
2001 case R_X86_64_GOTPC32:
2002 /* Use global offset table as symbol value. */
2003 relocation = htab->sgotplt->output_section->vma
2004 + htab->sgotplt->output_offset;
2005 unresolved_reloc = FALSE;
2008 case R_X86_64_PLT32:
2009 /* Relocation is to the entry for this symbol in the
2010 procedure linkage table. */
2012 /* Resolve a PLT32 reloc against a local symbol directly,
2013 without using the procedure linkage table. */
2017 if (h->plt.offset == (bfd_vma) -1
2018 || htab->splt == NULL)
2020 /* We didn't make a PLT entry for this symbol. This
2021 happens when statically linking PIC code, or when
2022 using -Bsymbolic. */
2026 relocation = (htab->splt->output_section->vma
2027 + htab->splt->output_offset
2029 unresolved_reloc = FALSE;
2036 && !SYMBOL_REFERENCES_LOCAL (info, h)
2037 && (input_section->flags & SEC_ALLOC) != 0
2038 && (input_section->flags & SEC_READONLY) != 0
2040 || r_type != R_X86_64_PC32
2041 || h->type != STT_FUNC
2042 || ELF_ST_VISIBILITY (h->other) != STV_PROTECTED
2043 || !is_32bit_relative_branch (contents,
2047 && r_type == R_X86_64_PC32
2048 && h->type == STT_FUNC
2049 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
2050 (*_bfd_error_handler)
2051 (_("%B: relocation R_X86_64_PC32 against protected function `%s' can not be used when making a shared object"),
2052 input_bfd, h->root.root.string);
2054 (*_bfd_error_handler)
2055 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
2056 input_bfd, x86_64_elf_howto_table[r_type].name,
2057 h->root.root.string);
2058 bfd_set_error (bfd_error_bad_value);
2068 /* FIXME: The ABI says the linker should make sure the value is
2069 the same when it's zeroextended to 64 bit. */
2071 /* r_symndx will be zero only for relocs against symbols
2072 from removed linkonce sections, or sections discarded by
2075 || (input_section->flags & SEC_ALLOC) == 0)
2080 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
2081 || h->root.type != bfd_link_hash_undefweak)
2082 && ((r_type != R_X86_64_PC8
2083 && r_type != R_X86_64_PC16
2084 && r_type != R_X86_64_PC32
2085 && r_type != R_X86_64_PC64)
2086 || !SYMBOL_CALLS_LOCAL (info, h)))
2087 || (ELIMINATE_COPY_RELOCS
2094 || h->root.type == bfd_link_hash_undefweak
2095 || h->root.type == bfd_link_hash_undefined)))
2097 Elf_Internal_Rela outrel;
2099 bfd_boolean skip, relocate;
2102 /* When generating a shared object, these relocations
2103 are copied into the output file to be resolved at run
2109 _bfd_elf_section_offset (output_bfd, info, input_section,
2111 if (outrel.r_offset == (bfd_vma) -1)
2113 else if (outrel.r_offset == (bfd_vma) -2)
2114 skip = TRUE, relocate = TRUE;
2116 outrel.r_offset += (input_section->output_section->vma
2117 + input_section->output_offset);
2120 memset (&outrel, 0, sizeof outrel);
2122 /* h->dynindx may be -1 if this symbol was marked to
2126 && (r_type == R_X86_64_PC8
2127 || r_type == R_X86_64_PC16
2128 || r_type == R_X86_64_PC32
2129 || r_type == R_X86_64_PC64
2132 || !h->def_regular))
2134 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
2135 outrel.r_addend = rel->r_addend;
2139 /* This symbol is local, or marked to become local. */
2140 if (r_type == R_X86_64_64)
2143 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2144 outrel.r_addend = relocation + rel->r_addend;
2150 if (bfd_is_abs_section (sec))
2152 else if (sec == NULL || sec->owner == NULL)
2154 bfd_set_error (bfd_error_bad_value);
2161 osec = sec->output_section;
2162 sindx = elf_section_data (osec)->dynindx;
2163 BFD_ASSERT (sindx > 0);
2166 outrel.r_info = ELF64_R_INFO (sindx, r_type);
2167 outrel.r_addend = relocation + rel->r_addend;
2171 sreloc = elf_section_data (input_section)->sreloc;
2175 loc = sreloc->contents;
2176 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
2177 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2179 /* If this reloc is against an external symbol, we do
2180 not want to fiddle with the addend. Otherwise, we
2181 need to include the symbol value so that it becomes
2182 an addend for the dynamic reloc. */
2189 case R_X86_64_TLSGD:
2190 case R_X86_64_GOTTPOFF:
2191 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
2192 tls_type = GOT_UNKNOWN;
2193 if (h == NULL && local_got_offsets)
2194 tls_type = elf64_x86_64_local_got_tls_type (input_bfd) [r_symndx];
2197 tls_type = elf64_x86_64_hash_entry (h)->tls_type;
2198 if (!info->shared && h->dynindx == -1 && tls_type == GOT_TLS_IE)
2199 r_type = R_X86_64_TPOFF32;
2201 if (r_type == R_X86_64_TLSGD)
2203 if (tls_type == GOT_TLS_IE)
2204 r_type = R_X86_64_GOTTPOFF;
2207 if (r_type == R_X86_64_TPOFF32)
2209 BFD_ASSERT (! unresolved_reloc);
2210 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
2213 static unsigned char tlsgd[8]
2214 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2216 /* GD->LE transition.
2217 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2218 .word 0x6666; rex64; call __tls_get_addr@plt
2221 leaq foo@tpoff(%rax), %rax */
2222 BFD_ASSERT (rel->r_offset >= 4);
2223 for (i = 0; i < 4; i++)
2224 BFD_ASSERT (bfd_get_8 (input_bfd,
2225 contents + rel->r_offset - 4 + i)
2227 BFD_ASSERT (rel->r_offset + 12 <= input_section->size);
2228 for (i = 0; i < 4; i++)
2229 BFD_ASSERT (bfd_get_8 (input_bfd,
2230 contents + rel->r_offset + 4 + i)
2232 BFD_ASSERT (rel + 1 < relend);
2233 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2234 memcpy (contents + rel->r_offset - 4,
2235 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0",
2237 bfd_put_32 (output_bfd, tpoff (info, relocation),
2238 contents + rel->r_offset + 8);
2239 /* Skip R_X86_64_PLT32. */
2245 unsigned int val, type, reg;
2247 /* IE->LE transition:
2248 Originally it can be one of:
2249 movq foo@gottpoff(%rip), %reg
2250 addq foo@gottpoff(%rip), %reg
2253 leaq foo(%reg), %reg
2255 BFD_ASSERT (rel->r_offset >= 3);
2256 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 3);
2257 BFD_ASSERT (val == 0x48 || val == 0x4c);
2258 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2259 BFD_ASSERT (type == 0x8b || type == 0x03);
2260 reg = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2261 BFD_ASSERT ((reg & 0xc7) == 5);
2263 BFD_ASSERT (rel->r_offset + 4 <= input_section->size);
2268 bfd_put_8 (output_bfd, 0x49,
2269 contents + rel->r_offset - 3);
2270 bfd_put_8 (output_bfd, 0xc7,
2271 contents + rel->r_offset - 2);
2272 bfd_put_8 (output_bfd, 0xc0 | reg,
2273 contents + rel->r_offset - 1);
2277 /* addq -> addq - addressing with %rsp/%r12 is
2280 bfd_put_8 (output_bfd, 0x49,
2281 contents + rel->r_offset - 3);
2282 bfd_put_8 (output_bfd, 0x81,
2283 contents + rel->r_offset - 2);
2284 bfd_put_8 (output_bfd, 0xc0 | reg,
2285 contents + rel->r_offset - 1);
2291 bfd_put_8 (output_bfd, 0x4d,
2292 contents + rel->r_offset - 3);
2293 bfd_put_8 (output_bfd, 0x8d,
2294 contents + rel->r_offset - 2);
2295 bfd_put_8 (output_bfd, 0x80 | reg | (reg << 3),
2296 contents + rel->r_offset - 1);
2298 bfd_put_32 (output_bfd, tpoff (info, relocation),
2299 contents + rel->r_offset);
2304 if (htab->sgot == NULL)
2308 off = h->got.offset;
2311 if (local_got_offsets == NULL)
2314 off = local_got_offsets[r_symndx];
2321 Elf_Internal_Rela outrel;
2325 if (htab->srelgot == NULL)
2328 outrel.r_offset = (htab->sgot->output_section->vma
2329 + htab->sgot->output_offset + off);
2331 indx = h && h->dynindx != -1 ? h->dynindx : 0;
2332 if (r_type == R_X86_64_TLSGD)
2333 dr_type = R_X86_64_DTPMOD64;
2335 dr_type = R_X86_64_TPOFF64;
2337 bfd_put_64 (output_bfd, 0, htab->sgot->contents + off);
2338 outrel.r_addend = 0;
2339 if (dr_type == R_X86_64_TPOFF64 && indx == 0)
2340 outrel.r_addend = relocation - dtpoff_base (info);
2341 outrel.r_info = ELF64_R_INFO (indx, dr_type);
2343 loc = htab->srelgot->contents;
2344 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2345 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2347 if (r_type == R_X86_64_TLSGD)
2351 BFD_ASSERT (! unresolved_reloc);
2352 bfd_put_64 (output_bfd,
2353 relocation - dtpoff_base (info),
2354 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2358 bfd_put_64 (output_bfd, 0,
2359 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2360 outrel.r_info = ELF64_R_INFO (indx,
2362 outrel.r_offset += GOT_ENTRY_SIZE;
2363 htab->srelgot->reloc_count++;
2364 loc += sizeof (Elf64_External_Rela);
2365 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2372 local_got_offsets[r_symndx] |= 1;
2375 if (off >= (bfd_vma) -2)
2377 if (r_type == ELF64_R_TYPE (rel->r_info))
2379 relocation = htab->sgot->output_section->vma
2380 + htab->sgot->output_offset + off;
2381 unresolved_reloc = FALSE;
2386 static unsigned char tlsgd[8]
2387 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2389 /* GD->IE transition.
2390 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2391 .word 0x6666; rex64; call __tls_get_addr@plt
2394 addq foo@gottpoff(%rip), %rax */
2395 BFD_ASSERT (rel->r_offset >= 4);
2396 for (i = 0; i < 4; i++)
2397 BFD_ASSERT (bfd_get_8 (input_bfd,
2398 contents + rel->r_offset - 4 + i)
2400 BFD_ASSERT (rel->r_offset + 12 <= input_section->size);
2401 for (i = 0; i < 4; i++)
2402 BFD_ASSERT (bfd_get_8 (input_bfd,
2403 contents + rel->r_offset + 4 + i)
2405 BFD_ASSERT (rel + 1 < relend);
2406 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2407 memcpy (contents + rel->r_offset - 4,
2408 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0",
2411 relocation = (htab->sgot->output_section->vma
2412 + htab->sgot->output_offset + off
2414 - input_section->output_section->vma
2415 - input_section->output_offset
2417 bfd_put_32 (output_bfd, relocation,
2418 contents + rel->r_offset + 8);
2419 /* Skip R_X86_64_PLT32. */
2425 case R_X86_64_TLSLD:
2428 /* LD->LE transition:
2430 leaq foo@tlsld(%rip), %rdi; call __tls_get_addr@plt.
2432 .word 0x6666; .byte 0x66; movl %fs:0, %rax. */
2433 BFD_ASSERT (rel->r_offset >= 3);
2434 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 3)
2436 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 2)
2438 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 1)
2440 BFD_ASSERT (rel->r_offset + 9 <= input_section->size);
2441 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2443 BFD_ASSERT (rel + 1 < relend);
2444 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2445 memcpy (contents + rel->r_offset - 3,
2446 "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0", 12);
2447 /* Skip R_X86_64_PLT32. */
2452 if (htab->sgot == NULL)
2455 off = htab->tls_ld_got.offset;
2460 Elf_Internal_Rela outrel;
2463 if (htab->srelgot == NULL)
2466 outrel.r_offset = (htab->sgot->output_section->vma
2467 + htab->sgot->output_offset + off);
2469 bfd_put_64 (output_bfd, 0,
2470 htab->sgot->contents + off);
2471 bfd_put_64 (output_bfd, 0,
2472 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2473 outrel.r_info = ELF64_R_INFO (0, R_X86_64_DTPMOD64);
2474 outrel.r_addend = 0;
2475 loc = htab->srelgot->contents;
2476 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2477 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2478 htab->tls_ld_got.offset |= 1;
2480 relocation = htab->sgot->output_section->vma
2481 + htab->sgot->output_offset + off;
2482 unresolved_reloc = FALSE;
2485 case R_X86_64_DTPOFF32:
2486 if (info->shared || (input_section->flags & SEC_CODE) == 0)
2487 relocation -= dtpoff_base (info);
2489 relocation = tpoff (info, relocation);
2492 case R_X86_64_TPOFF32:
2493 BFD_ASSERT (! info->shared);
2494 relocation = tpoff (info, relocation);
2501 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
2502 because such sections are not SEC_ALLOC and thus ld.so will
2503 not process them. */
2504 if (unresolved_reloc
2505 && !((input_section->flags & SEC_DEBUGGING) != 0
2507 (*_bfd_error_handler)
2508 (_("%B(%A+0x%lx): unresolvable relocation against symbol `%s'"),
2511 (long) rel->r_offset,
2512 h->root.root.string);
2514 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
2515 contents, rel->r_offset,
2516 relocation, rel->r_addend);
2518 if (r != bfd_reloc_ok)
2523 name = h->root.root.string;
2526 name = bfd_elf_string_from_elf_section (input_bfd,
2527 symtab_hdr->sh_link,
2532 name = bfd_section_name (input_bfd, sec);
2535 if (r == bfd_reloc_overflow)
2538 && h->root.type == bfd_link_hash_undefweak
2539 && howto->pc_relative)
2540 /* Ignore reloc overflow on branches to undefweak syms. */
2543 if (! ((*info->callbacks->reloc_overflow)
2544 (info, (h ? &h->root : NULL), name, howto->name,
2545 (bfd_vma) 0, input_bfd, input_section,
2551 (*_bfd_error_handler)
2552 (_("%B(%A+0x%lx): reloc against `%s': error %d"),
2553 input_bfd, input_section,
2554 (long) rel->r_offset, name, (int) r);
2563 /* Finish up dynamic symbol handling. We set the contents of various
2564 dynamic sections here. */
2567 elf64_x86_64_finish_dynamic_symbol (bfd *output_bfd,
2568 struct bfd_link_info *info,
2569 struct elf_link_hash_entry *h,
2570 Elf_Internal_Sym *sym)
2572 struct elf64_x86_64_link_hash_table *htab;
2574 htab = elf64_x86_64_hash_table (info);
2576 if (h->plt.offset != (bfd_vma) -1)
2580 Elf_Internal_Rela rela;
2583 /* This symbol has an entry in the procedure linkage table. Set
2585 if (h->dynindx == -1
2586 || htab->splt == NULL
2587 || htab->sgotplt == NULL
2588 || htab->srelplt == NULL)
2591 /* Get the index in the procedure linkage table which
2592 corresponds to this symbol. This is the index of this symbol
2593 in all the symbols for which we are making plt entries. The
2594 first entry in the procedure linkage table is reserved. */
2595 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2597 /* Get the offset into the .got table of the entry that
2598 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
2599 bytes. The first three are reserved for the dynamic linker. */
2600 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
2602 /* Fill in the entry in the procedure linkage table. */
2603 memcpy (htab->splt->contents + h->plt.offset, elf64_x86_64_plt_entry,
2606 /* Insert the relocation positions of the plt section. The magic
2607 numbers at the end of the statements are the positions of the
2608 relocations in the plt section. */
2609 /* Put offset for jmp *name@GOTPCREL(%rip), since the
2610 instruction uses 6 bytes, subtract this value. */
2611 bfd_put_32 (output_bfd,
2612 (htab->sgotplt->output_section->vma
2613 + htab->sgotplt->output_offset
2615 - htab->splt->output_section->vma
2616 - htab->splt->output_offset
2619 htab->splt->contents + h->plt.offset + 2);
2620 /* Put relocation index. */
2621 bfd_put_32 (output_bfd, plt_index,
2622 htab->splt->contents + h->plt.offset + 7);
2623 /* Put offset for jmp .PLT0. */
2624 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
2625 htab->splt->contents + h->plt.offset + 12);
2627 /* Fill in the entry in the global offset table, initially this
2628 points to the pushq instruction in the PLT which is at offset 6. */
2629 bfd_put_64 (output_bfd, (htab->splt->output_section->vma
2630 + htab->splt->output_offset
2631 + h->plt.offset + 6),
2632 htab->sgotplt->contents + got_offset);
2634 /* Fill in the entry in the .rela.plt section. */
2635 rela.r_offset = (htab->sgotplt->output_section->vma
2636 + htab->sgotplt->output_offset
2638 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
2640 loc = htab->srelplt->contents + plt_index * sizeof (Elf64_External_Rela);
2641 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2643 if (!h->def_regular)
2645 /* Mark the symbol as undefined, rather than as defined in
2646 the .plt section. Leave the value if there were any
2647 relocations where pointer equality matters (this is a clue
2648 for the dynamic linker, to make function pointer
2649 comparisons work between an application and shared
2650 library), otherwise set it to zero. If a function is only
2651 called from a binary, there is no need to slow down
2652 shared libraries because of that. */
2653 sym->st_shndx = SHN_UNDEF;
2654 if (!h->pointer_equality_needed)
2659 if (h->got.offset != (bfd_vma) -1
2660 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_GD
2661 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE)
2663 Elf_Internal_Rela rela;
2666 /* This symbol has an entry in the global offset table. Set it
2668 if (htab->sgot == NULL || htab->srelgot == NULL)
2671 rela.r_offset = (htab->sgot->output_section->vma
2672 + htab->sgot->output_offset
2673 + (h->got.offset &~ (bfd_vma) 1));
2675 /* If this is a static link, or it is a -Bsymbolic link and the
2676 symbol is defined locally or was forced to be local because
2677 of a version file, we just want to emit a RELATIVE reloc.
2678 The entry in the global offset table will already have been
2679 initialized in the relocate_section function. */
2681 && SYMBOL_REFERENCES_LOCAL (info, h))
2683 BFD_ASSERT((h->got.offset & 1) != 0);
2684 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2685 rela.r_addend = (h->root.u.def.value
2686 + h->root.u.def.section->output_section->vma
2687 + h->root.u.def.section->output_offset);
2691 BFD_ASSERT((h->got.offset & 1) == 0);
2692 bfd_put_64 (output_bfd, (bfd_vma) 0,
2693 htab->sgot->contents + h->got.offset);
2694 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
2698 loc = htab->srelgot->contents;
2699 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2700 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2705 Elf_Internal_Rela rela;
2708 /* This symbol needs a copy reloc. Set it up. */
2710 if (h->dynindx == -1
2711 || (h->root.type != bfd_link_hash_defined
2712 && h->root.type != bfd_link_hash_defweak)
2713 || htab->srelbss == NULL)
2716 rela.r_offset = (h->root.u.def.value
2717 + h->root.u.def.section->output_section->vma
2718 + h->root.u.def.section->output_offset);
2719 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
2721 loc = htab->srelbss->contents;
2722 loc += htab->srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
2723 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2726 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
2727 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
2728 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
2729 sym->st_shndx = SHN_ABS;
2734 /* Used to decide how to sort relocs in an optimal manner for the
2735 dynamic linker, before writing them out. */
2737 static enum elf_reloc_type_class
2738 elf64_x86_64_reloc_type_class (const Elf_Internal_Rela *rela)
2740 switch ((int) ELF64_R_TYPE (rela->r_info))
2742 case R_X86_64_RELATIVE:
2743 return reloc_class_relative;
2744 case R_X86_64_JUMP_SLOT:
2745 return reloc_class_plt;
2747 return reloc_class_copy;
2749 return reloc_class_normal;
2753 /* Finish up the dynamic sections. */
2756 elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
2758 struct elf64_x86_64_link_hash_table *htab;
2762 htab = elf64_x86_64_hash_table (info);
2763 dynobj = htab->elf.dynobj;
2764 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2766 if (htab->elf.dynamic_sections_created)
2768 Elf64_External_Dyn *dyncon, *dynconend;
2770 if (sdyn == NULL || htab->sgot == NULL)
2773 dyncon = (Elf64_External_Dyn *) sdyn->contents;
2774 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->size);
2775 for (; dyncon < dynconend; dyncon++)
2777 Elf_Internal_Dyn dyn;
2780 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
2789 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
2793 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
2797 s = htab->srelplt->output_section;
2798 dyn.d_un.d_val = s->size;
2802 /* The procedure linkage table relocs (DT_JMPREL) should
2803 not be included in the overall relocs (DT_RELA).
2804 Therefore, we override the DT_RELASZ entry here to
2805 make it not include the JMPREL relocs. Since the
2806 linker script arranges for .rela.plt to follow all
2807 other relocation sections, we don't have to worry
2808 about changing the DT_RELA entry. */
2809 if (htab->srelplt != NULL)
2811 s = htab->srelplt->output_section;
2812 dyn.d_un.d_val -= s->size;
2817 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
2820 /* Fill in the special first entry in the procedure linkage table. */
2821 if (htab->splt && htab->splt->size > 0)
2823 /* Fill in the first entry in the procedure linkage table. */
2824 memcpy (htab->splt->contents, elf64_x86_64_plt0_entry,
2826 /* Add offset for pushq GOT+8(%rip), since the instruction
2827 uses 6 bytes subtract this value. */
2828 bfd_put_32 (output_bfd,
2829 (htab->sgotplt->output_section->vma
2830 + htab->sgotplt->output_offset
2832 - htab->splt->output_section->vma
2833 - htab->splt->output_offset
2835 htab->splt->contents + 2);
2836 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
2837 the end of the instruction. */
2838 bfd_put_32 (output_bfd,
2839 (htab->sgotplt->output_section->vma
2840 + htab->sgotplt->output_offset
2842 - htab->splt->output_section->vma
2843 - htab->splt->output_offset
2845 htab->splt->contents + 8);
2847 elf_section_data (htab->splt->output_section)->this_hdr.sh_entsize =
2854 /* Fill in the first three entries in the global offset table. */
2855 if (htab->sgotplt->size > 0)
2857 /* Set the first entry in the global offset table to the address of
2858 the dynamic section. */
2860 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents);
2862 bfd_put_64 (output_bfd,
2863 sdyn->output_section->vma + sdyn->output_offset,
2864 htab->sgotplt->contents);
2865 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
2866 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE);
2867 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE*2);
2870 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize =
2874 if (htab->sgot && htab->sgot->size > 0)
2875 elf_section_data (htab->sgot->output_section)->this_hdr.sh_entsize
2881 /* Return address for Ith PLT stub in section PLT, for relocation REL
2882 or (bfd_vma) -1 if it should not be included. */
2885 elf64_x86_64_plt_sym_val (bfd_vma i, const asection *plt,
2886 const arelent *rel ATTRIBUTE_UNUSED)
2888 return plt->vma + (i + 1) * PLT_ENTRY_SIZE;
2891 /* Handle an x86-64 specific section when reading an object file. This
2892 is called when elfcode.h finds a section with an unknown type. */
2895 elf64_x86_64_section_from_shdr (bfd *abfd,
2896 Elf_Internal_Shdr *hdr,
2900 if (hdr->sh_type != SHT_X86_64_UNWIND)
2903 if (! _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex))
2909 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
2910 #define TARGET_LITTLE_NAME "elf64-x86-64"
2911 #define ELF_ARCH bfd_arch_i386
2912 #define ELF_MACHINE_CODE EM_X86_64
2913 #define ELF_MAXPAGESIZE 0x100000
2915 #define elf_backend_can_gc_sections 1
2916 #define elf_backend_can_refcount 1
2917 #define elf_backend_want_got_plt 1
2918 #define elf_backend_plt_readonly 1
2919 #define elf_backend_want_plt_sym 0
2920 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
2921 #define elf_backend_rela_normal 1
2923 #define elf_info_to_howto elf64_x86_64_info_to_howto
2925 #define bfd_elf64_bfd_link_hash_table_create \
2926 elf64_x86_64_link_hash_table_create
2927 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
2929 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
2930 #define elf_backend_check_relocs elf64_x86_64_check_relocs
2931 #define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol
2932 #define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections
2933 #define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections
2934 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
2935 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
2936 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
2937 #define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus
2938 #define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo
2939 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
2940 #define elf_backend_relocate_section elf64_x86_64_relocate_section
2941 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
2942 #define elf_backend_plt_sym_val elf64_x86_64_plt_sym_val
2943 #define elf_backend_object_p elf64_x86_64_elf_object_p
2944 #define bfd_elf64_mkobject elf64_x86_64_mkobject
2946 #define elf_backend_section_from_shdr \
2947 elf64_x86_64_section_from_shdr
2949 #include "elf64-target.h"