2001-11-22 H.J. Lu <hjl@gnu.org>
[binutils.git] / bfd / elf64-x86-64.c
blobdf303e7e034727faea743bd9c3bd1f697f6bb70c
1 /* X86-64 specific support for 64-bit ELF
2 Copyright 2000, 2001 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 "libbfd.h"
24 #include "elf-bfd.h"
26 #include "elf/x86-64.h"
28 /* We use only the RELA entries. */
29 #define USE_RELA
31 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
32 #define MINUS_ONE (~ (bfd_vma) 0)
34 /* The relocation "howto" table. Order of fields:
35 type, size, bitsize, pc_relative, complain_on_overflow,
36 special_function, name, partial_inplace, src_mask, dst_pack, pcrel_offset. */
37 static reloc_howto_type x86_64_elf_howto_table[] =
39 HOWTO(R_X86_64_NONE, 0, 0, 0, false, 0, complain_overflow_dont,
40 bfd_elf_generic_reloc, "R_X86_64_NONE", false, 0x00000000, 0x00000000,
41 false),
42 HOWTO(R_X86_64_64, 0, 4, 64, false, 0, complain_overflow_bitfield,
43 bfd_elf_generic_reloc, "R_X86_64_64", false, MINUS_ONE, MINUS_ONE,
44 false),
45 HOWTO(R_X86_64_PC32, 0, 4, 32, true, 0, complain_overflow_signed,
46 bfd_elf_generic_reloc, "R_X86_64_PC32", false, 0xffffffff, 0xffffffff,
47 true),
48 HOWTO(R_X86_64_GOT32, 0, 4, 32, false, 0, complain_overflow_signed,
49 bfd_elf_generic_reloc, "R_X86_64_GOT32", false, 0xffffffff, 0xffffffff,
50 false),
51 HOWTO(R_X86_64_PLT32, 0, 4, 32, true, 0, complain_overflow_signed,
52 bfd_elf_generic_reloc, "R_X86_64_PLT32", false, 0xffffffff, 0xffffffff,
53 true),
54 HOWTO(R_X86_64_COPY, 0, 4, 32, false, 0, complain_overflow_bitfield,
55 bfd_elf_generic_reloc, "R_X86_64_COPY", false, 0xffffffff, 0xffffffff,
56 false),
57 HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, false, 0, complain_overflow_bitfield,
58 bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", false, MINUS_ONE,
59 MINUS_ONE, false),
60 HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, false, 0, complain_overflow_bitfield,
61 bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", false, MINUS_ONE,
62 MINUS_ONE, false),
63 HOWTO(R_X86_64_RELATIVE, 0, 4, 64, false, 0, complain_overflow_bitfield,
64 bfd_elf_generic_reloc, "R_X86_64_RELATIVE", false, MINUS_ONE,
65 MINUS_ONE, false),
66 HOWTO(R_X86_64_GOTPCREL, 0, 4, 32, true,0 , complain_overflow_signed,
67 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", false, 0xffffffff,
68 0xffffffff, true),
69 HOWTO(R_X86_64_32, 0, 4, 32, false, 0, complain_overflow_unsigned,
70 bfd_elf_generic_reloc, "R_X86_64_32", false, 0xffffffff, 0xffffffff,
71 false),
72 HOWTO(R_X86_64_32S, 0, 4, 32, false, 0, complain_overflow_signed,
73 bfd_elf_generic_reloc, "R_X86_64_32S", false, 0xffffffff, 0xffffffff,
74 false),
75 HOWTO(R_X86_64_16, 0, 1, 16, false, 0, complain_overflow_bitfield,
76 bfd_elf_generic_reloc, "R_X86_64_16", false, 0xffff, 0xffff, false),
77 HOWTO(R_X86_64_PC16,0, 1, 16, true, 0, complain_overflow_bitfield,
78 bfd_elf_generic_reloc, "R_X86_64_PC16", false, 0xffff, 0xffff, true),
79 HOWTO(R_X86_64_8, 0, 0, 8, false, 0, complain_overflow_signed,
80 bfd_elf_generic_reloc, "R_X86_64_8", false, 0xff, 0xff, false),
81 HOWTO(R_X86_64_PC8, 0, 0, 8, true, 0, complain_overflow_signed,
82 bfd_elf_generic_reloc, "R_X86_64_PC8", false, 0xff, 0xff, true),
84 /* GNU extension to record C++ vtable hierarchy. */
85 HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, false, 0, complain_overflow_dont,
86 NULL, "R_X86_64_GNU_VTINHERIT", false, 0, 0, false),
88 /* GNU extension to record C++ vtable member usage. */
89 HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, false, 0, complain_overflow_dont,
90 _bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", false, 0, 0,
91 false)
94 /* Map BFD relocs to the x86_64 elf relocs. */
95 struct elf_reloc_map
97 bfd_reloc_code_real_type bfd_reloc_val;
98 unsigned char elf_reloc_val;
101 static const struct elf_reloc_map x86_64_reloc_map[] =
103 { BFD_RELOC_NONE, R_X86_64_NONE, },
104 { BFD_RELOC_64, R_X86_64_64, },
105 { BFD_RELOC_32_PCREL, R_X86_64_PC32, },
106 { BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,},
107 { BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,},
108 { BFD_RELOC_X86_64_COPY, R_X86_64_COPY, },
109 { BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, },
110 { BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, },
111 { BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, },
112 { BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, },
113 { BFD_RELOC_32, R_X86_64_32, },
114 { BFD_RELOC_X86_64_32S, R_X86_64_32S, },
115 { BFD_RELOC_16, R_X86_64_16, },
116 { BFD_RELOC_16_PCREL, R_X86_64_PC16, },
117 { BFD_RELOC_8, R_X86_64_8, },
118 { BFD_RELOC_8_PCREL, R_X86_64_PC8, },
119 { BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
120 { BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
123 static reloc_howto_type *elf64_x86_64_reloc_type_lookup
124 PARAMS ((bfd *, bfd_reloc_code_real_type));
125 static void elf64_x86_64_info_to_howto
126 PARAMS ((bfd *, arelent *, Elf64_Internal_Rela *));
127 static struct bfd_link_hash_table *elf64_x86_64_link_hash_table_create
128 PARAMS ((bfd *));
129 static boolean elf64_x86_64_elf_object_p PARAMS ((bfd *abfd));
130 static boolean elf64_x86_64_check_relocs
131 PARAMS ((bfd *, struct bfd_link_info *, asection *sec,
132 const Elf_Internal_Rela *));
133 static asection *elf64_x86_64_gc_mark_hook
134 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
135 struct elf_link_hash_entry *, Elf_Internal_Sym *));
137 static boolean elf64_x86_64_gc_sweep_hook
138 PARAMS ((bfd *, struct bfd_link_info *, asection *,
139 const Elf_Internal_Rela *));
141 static struct bfd_hash_entry *elf64_x86_64_link_hash_newfunc
142 PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
143 static boolean elf64_x86_64_adjust_dynamic_symbol
144 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
146 static boolean elf64_x86_64_size_dynamic_sections
147 PARAMS ((bfd *, struct bfd_link_info *));
148 static boolean elf64_x86_64_relocate_section
149 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
150 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
151 static boolean elf64_x86_64_finish_dynamic_symbol
152 PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
153 Elf_Internal_Sym *sym));
154 static boolean elf64_x86_64_finish_dynamic_sections
155 PARAMS ((bfd *, struct bfd_link_info *));
156 static enum elf_reloc_type_class elf64_x86_64_reloc_type_class
157 PARAMS ((const Elf_Internal_Rela *));
159 /* Given a BFD reloc type, return a HOWTO structure. */
160 static reloc_howto_type *
161 elf64_x86_64_reloc_type_lookup (abfd, code)
162 bfd *abfd ATTRIBUTE_UNUSED;
163 bfd_reloc_code_real_type code;
165 unsigned int i;
166 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
167 i++)
169 if (x86_64_reloc_map[i].bfd_reloc_val == code)
170 return &x86_64_elf_howto_table[i];
172 return 0;
175 /* Given an x86_64 ELF reloc type, fill in an arelent structure. */
177 static void
178 elf64_x86_64_info_to_howto (abfd, cache_ptr, dst)
179 bfd *abfd ATTRIBUTE_UNUSED;
180 arelent *cache_ptr;
181 Elf64_Internal_Rela *dst;
183 unsigned r_type, i;
185 r_type = ELF64_R_TYPE (dst->r_info);
186 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT)
188 BFD_ASSERT (r_type <= (unsigned int) R_X86_64_PC8);
189 i = r_type;
191 else
193 BFD_ASSERT (r_type < (unsigned int) R_X86_64_max);
194 i = r_type - ((unsigned int) R_X86_64_GNU_VTINHERIT - R_X86_64_PC8 - 1);
196 cache_ptr->howto = &x86_64_elf_howto_table[i];
197 BFD_ASSERT (r_type == cache_ptr->howto->type);
200 /* Functions for the x86-64 ELF linker. */
202 /* The name of the dynamic interpreter. This is put in the .interp
203 section. */
205 #define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
207 /* The size in bytes of an entry in the global offset table. */
209 #define GOT_ENTRY_SIZE 8
211 /* The size in bytes of an entry in the procedure linkage table. */
213 #define PLT_ENTRY_SIZE 16
215 /* The first entry in a procedure linkage table looks like this. See the
216 SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
218 static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
220 0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
221 0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
222 0x90, 0x90, 0x90, 0x90 /* pad out to 16 bytes with nops. */
225 /* Subsequent entries in a procedure linkage table look like this. */
227 static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
229 0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
230 0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
231 0x68, /* pushq immediate */
232 0, 0, 0, 0, /* replaced with index into relocation table. */
233 0xe9, /* jmp relative */
234 0, 0, 0, 0 /* replaced with offset to start of .plt0. */
237 /* The x86-64 linker needs to keep track of the number of relocs that
238 it decides to copy in check_relocs for each symbol. This is so
239 that it can discard PC relative relocs if it doesn't need them when
240 linking with -Bsymbolic. We store the information in a field
241 extending the regular ELF linker hash table. */
243 /* This structure keeps track of the number of PC relative relocs we
244 have copied for a given symbol. */
246 struct elf64_x86_64_pcrel_relocs_copied
248 /* Next section. */
249 struct elf64_x86_64_pcrel_relocs_copied *next;
250 /* A section in dynobj. */
251 asection *section;
252 /* Number of relocs copied in this section. */
253 bfd_size_type count;
256 /* x86-64 ELF linker hash entry. */
258 struct elf64_x86_64_link_hash_entry
260 struct elf_link_hash_entry root;
262 /* Number of PC relative relocs copied for this symbol. */
263 struct elf64_x86_64_pcrel_relocs_copied *pcrel_relocs_copied;
266 /* x86-64 ELF linker hash table. */
268 struct elf64_x86_64_link_hash_table
270 struct elf_link_hash_table root;
273 /* Declare this now that the above structures are defined. */
275 static boolean elf64_x86_64_discard_copies
276 PARAMS ((struct elf64_x86_64_link_hash_entry *, PTR));
278 /* Traverse an x86-64 ELF linker hash table. */
280 #define elf64_x86_64_link_hash_traverse(table, func, info) \
281 (elf_link_hash_traverse \
282 (&(table)->root, \
283 (boolean (*) PARAMS ((struct elf_link_hash_entry *, PTR))) (func), \
284 (info)))
286 /* Get the x86-64 ELF linker hash table from a link_info structure. */
288 #define elf64_x86_64_hash_table(p) \
289 ((struct elf64_x86_64_link_hash_table *) ((p)->hash))
291 /* Create an entry in an x86-64 ELF linker hash table. */
293 static struct bfd_hash_entry *
294 elf64_x86_64_link_hash_newfunc (entry, table, string)
295 struct bfd_hash_entry *entry;
296 struct bfd_hash_table *table;
297 const char *string;
299 struct elf64_x86_64_link_hash_entry *ret =
300 (struct elf64_x86_64_link_hash_entry *) entry;
302 /* Allocate the structure if it has not already been allocated by a
303 subclass. */
304 if (ret == (struct elf64_x86_64_link_hash_entry *) NULL)
305 ret = ((struct elf64_x86_64_link_hash_entry *)
306 bfd_hash_allocate (table,
307 sizeof (struct elf64_x86_64_link_hash_entry)));
308 if (ret == (struct elf64_x86_64_link_hash_entry *) NULL)
309 return (struct bfd_hash_entry *) ret;
311 /* Call the allocation method of the superclass. */
312 ret = ((struct elf64_x86_64_link_hash_entry *)
313 _bfd_elf_link_hash_newfunc ((struct bfd_hash_entry *) ret,
314 table, string));
315 if (ret != (struct elf64_x86_64_link_hash_entry *) NULL)
317 ret->pcrel_relocs_copied = NULL;
320 return (struct bfd_hash_entry *) ret;
323 /* Create an X86-64 ELF linker hash table. */
325 static struct bfd_link_hash_table *
326 elf64_x86_64_link_hash_table_create (abfd)
327 bfd *abfd;
329 struct elf64_x86_64_link_hash_table *ret;
330 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table);
332 ret = ((struct elf64_x86_64_link_hash_table *) bfd_alloc (abfd, amt));
333 if (ret == (struct elf64_x86_64_link_hash_table *) NULL)
334 return NULL;
336 if (! _bfd_elf_link_hash_table_init (&ret->root, abfd,
337 elf64_x86_64_link_hash_newfunc))
339 bfd_release (abfd, ret);
340 return NULL;
343 return &ret->root.root;
346 static boolean
347 elf64_x86_64_elf_object_p (abfd)
348 bfd *abfd;
350 /* Set the right machine number for an x86-64 elf64 file. */
351 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
352 return true;
355 /* Look through the relocs for a section during the first phase, and
356 allocate space in the global offset table or procedure linkage
357 table. */
359 static boolean
360 elf64_x86_64_check_relocs (abfd, info, sec, relocs)
361 bfd *abfd;
362 struct bfd_link_info *info;
363 asection *sec;
364 const Elf_Internal_Rela *relocs;
366 bfd *dynobj;
367 Elf_Internal_Shdr *symtab_hdr;
368 struct elf_link_hash_entry **sym_hashes;
369 bfd_signed_vma *local_got_refcounts;
370 const Elf_Internal_Rela *rel;
371 const Elf_Internal_Rela *rel_end;
372 asection *sgot;
373 asection *srelgot;
374 asection *sreloc;
376 if (info->relocateable)
377 return true;
379 dynobj = elf_hash_table (info)->dynobj;
380 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
381 sym_hashes = elf_sym_hashes (abfd);
382 local_got_refcounts = elf_local_got_refcounts (abfd);
384 sgot = srelgot = sreloc = NULL;
385 rel_end = relocs + sec->reloc_count;
386 for (rel = relocs; rel < rel_end; rel++)
388 unsigned long r_symndx;
389 struct elf_link_hash_entry *h;
391 r_symndx = ELF64_R_SYM (rel->r_info);
392 if (r_symndx < symtab_hdr->sh_info)
393 h = NULL;
394 else
395 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
397 /* Some relocs require a global offset table. */
398 if (dynobj == NULL)
400 switch (ELF64_R_TYPE (rel->r_info))
402 case R_X86_64_GOT32:
403 case R_X86_64_GOTPCREL:
404 elf_hash_table (info)->dynobj = dynobj = abfd;
405 if (! _bfd_elf_create_got_section (dynobj, info))
406 return false;
407 break;
411 switch (ELF64_R_TYPE (rel->r_info))
413 case R_X86_64_GOTPCREL:
414 case R_X86_64_GOT32:
415 /* This symbol requires a global offset table entry. */
417 if (sgot == NULL)
419 sgot = bfd_get_section_by_name (dynobj, ".got");
420 BFD_ASSERT (sgot != NULL);
423 if (srelgot == NULL && (h != NULL || info->shared))
425 srelgot = bfd_get_section_by_name (dynobj, ".rela.got");
426 if (srelgot == NULL)
428 srelgot = bfd_make_section (dynobj, ".rela.got");
429 if (srelgot == NULL
430 || ! bfd_set_section_flags (dynobj, srelgot,
431 (SEC_ALLOC
432 | SEC_LOAD
433 | SEC_HAS_CONTENTS
434 | SEC_IN_MEMORY
435 | SEC_LINKER_CREATED
436 | SEC_READONLY))
437 || ! bfd_set_section_alignment (dynobj, srelgot, 3))
438 return false;
442 if (h != NULL)
444 if (h->got.refcount == 0)
446 /* Make sure this symbol is output as a dynamic symbol. */
447 if (h->dynindx == -1)
449 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
450 return false;
453 sgot->_raw_size += GOT_ENTRY_SIZE;
454 srelgot->_raw_size += sizeof (Elf64_External_Rela);
456 h->got.refcount += 1;
458 else
460 /* This is a global offset table entry for a local symbol. */
461 if (local_got_refcounts == NULL)
463 bfd_size_type size;
465 size = symtab_hdr->sh_info;
466 size *= sizeof (bfd_signed_vma);
467 local_got_refcounts = ((bfd_signed_vma *)
468 bfd_zalloc (abfd, size));
469 if (local_got_refcounts == NULL)
470 return false;
471 elf_local_got_refcounts (abfd) = local_got_refcounts;
473 if (local_got_refcounts[r_symndx] == 0)
475 sgot->_raw_size += GOT_ENTRY_SIZE;
476 if (info->shared)
478 /* If we are generating a shared object, we need to
479 output a R_X86_64_RELATIVE reloc so that the dynamic
480 linker can adjust this GOT entry. */
481 srelgot->_raw_size += sizeof (Elf64_External_Rela);
484 local_got_refcounts[r_symndx] += 1;
486 break;
488 case R_X86_64_PLT32:
489 /* This symbol requires a procedure linkage table entry. We
490 actually build the entry in adjust_dynamic_symbol,
491 because this might be a case of linking PIC code which is
492 never referenced by a dynamic object, in which case we
493 don't need to generate a procedure linkage table entry
494 after all. */
496 /* If this is a local symbol, we resolve it directly without
497 creating a procedure linkage table entry. */
498 if (h == NULL)
499 continue;
501 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
502 h->plt.refcount += 1;
503 break;
505 case R_X86_64_8:
506 case R_X86_64_16:
507 case R_X86_64_32:
508 case R_X86_64_64:
509 case R_X86_64_32S:
510 case R_X86_64_PC32:
511 if (h != NULL)
512 h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF;
514 /* If we are creating a shared library, and this is a reloc
515 against a global symbol, or a non PC relative reloc
516 against a local symbol, then we need to copy the reloc
517 into the shared library. However, if we are linking with
518 -Bsymbolic, we do not need to copy a reloc against a
519 global symbol which is defined in an object we are
520 including in the link (i.e., DEF_REGULAR is set). At
521 this point we have not seen all the input files, so it is
522 possible that DEF_REGULAR is not set now but will be set
523 later (it is never cleared). We account for that
524 possibility below by storing information in the
525 pcrel_relocs_copied field of the hash table entry.
526 A similar situation occurs when creating shared libraries
527 and symbol visibility changes render the symbol local. */
528 if (info->shared
529 && (sec->flags & SEC_ALLOC) != 0
530 && (((ELF64_R_TYPE (rel->r_info) != R_X86_64_PC8)
531 && (ELF64_R_TYPE (rel->r_info) != R_X86_64_PC16)
532 && (ELF64_R_TYPE (rel->r_info) != R_X86_64_PC32))
533 || (h != NULL
534 && (! info->symbolic
535 || (h->elf_link_hash_flags
536 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
538 /* When creating a shared object, we must copy these
539 reloc types into the output file. We create a reloc
540 section in dynobj and make room for this reloc. */
541 if (sreloc == NULL)
543 const char *name;
545 name = (bfd_elf_string_from_elf_section
546 (abfd,
547 elf_elfheader (abfd)->e_shstrndx,
548 elf_section_data (sec)->rel_hdr.sh_name));
549 if (name == NULL)
550 return false;
552 BFD_ASSERT (strncmp (name, ".rela", 5) == 0
553 && strcmp (bfd_get_section_name (abfd, sec),
554 name + 5) == 0);
556 sreloc = bfd_get_section_by_name (dynobj, name);
557 if (sreloc == NULL)
559 flagword flags;
561 sreloc = bfd_make_section (dynobj, name);
562 flags = (SEC_HAS_CONTENTS | SEC_READONLY
563 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
564 if ((sec->flags & SEC_ALLOC) != 0)
565 flags |= SEC_ALLOC | SEC_LOAD;
566 if (sreloc == NULL
567 || ! bfd_set_section_flags (dynobj, sreloc, flags)
568 || ! bfd_set_section_alignment (dynobj, sreloc, 3))
569 return false;
571 if (sec->flags & SEC_READONLY)
572 info->flags |= DF_TEXTREL;
575 sreloc->_raw_size += sizeof (Elf64_External_Rela);
577 /* If this is a global symbol, we count the number of PC
578 relative relocations we have entered for this symbol,
579 so that we can discard them later as necessary. Note
580 that this function is only called if we are using an
581 elf64_x86_64 linker hash table, which means that h is
582 really a pointer to an elf64_x86_64_link_hash_entry. */
583 if (h != NULL
584 && ((ELF64_R_TYPE (rel->r_info) == R_X86_64_PC8)
585 || (ELF64_R_TYPE (rel->r_info) == R_X86_64_PC16)
586 || (ELF64_R_TYPE (rel->r_info) == R_X86_64_PC32)))
588 struct elf64_x86_64_link_hash_entry *eh;
589 struct elf64_x86_64_pcrel_relocs_copied *p;
591 eh = (struct elf64_x86_64_link_hash_entry *) h;
593 for (p = eh->pcrel_relocs_copied; p != NULL; p = p->next)
594 if (p->section == sreloc)
595 break;
597 if (p == NULL)
599 p = ((struct elf64_x86_64_pcrel_relocs_copied *)
600 bfd_alloc (dynobj, (bfd_size_type) sizeof *p));
601 if (p == NULL)
602 return false;
603 p->next = eh->pcrel_relocs_copied;
604 eh->pcrel_relocs_copied = p;
605 p->section = sreloc;
606 p->count = 0;
609 ++p->count;
612 break;
614 /* This relocation describes the C++ object vtable hierarchy.
615 Reconstruct it for later use during GC. */
616 case R_X86_64_GNU_VTINHERIT:
617 if (!_bfd_elf64_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
618 return false;
619 break;
621 /* This relocation describes which C++ vtable entries are actually
622 used. Record for later use during GC. */
623 case R_X86_64_GNU_VTENTRY:
624 if (!_bfd_elf64_gc_record_vtentry (abfd, sec, h, rel->r_addend))
625 return false;
626 break;
630 return true;
633 /* Return the section that should be marked against GC for a given
634 relocation. */
636 static asection *
637 elf64_x86_64_gc_mark_hook (abfd, info, rel, h, sym)
638 bfd *abfd;
639 struct bfd_link_info *info ATTRIBUTE_UNUSED;
640 Elf_Internal_Rela *rel ATTRIBUTE_UNUSED;
641 struct elf_link_hash_entry *h;
642 Elf_Internal_Sym *sym;
644 if (h != NULL)
646 switch (ELF64_R_TYPE (rel->r_info))
648 case R_X86_64_GNU_VTINHERIT:
649 case R_X86_64_GNU_VTENTRY:
650 break;
652 default:
653 switch (h->root.type)
655 case bfd_link_hash_defined:
656 case bfd_link_hash_defweak:
657 return h->root.u.def.section;
659 case bfd_link_hash_common:
660 return h->root.u.c.p->section;
662 default:
663 break;
667 else
669 if (!(elf_bad_symtab (abfd)
670 && ELF_ST_BIND (sym->st_info) != STB_LOCAL)
671 && ! ((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
672 && sym->st_shndx != SHN_COMMON))
674 return bfd_section_from_elf_index (abfd, sym->st_shndx);
678 return NULL;
681 /* Update the got entry reference counts for the section being removed. */
683 static boolean
684 elf64_x86_64_gc_sweep_hook (abfd, info, sec, relocs)
685 bfd *abfd;
686 struct bfd_link_info *info ATTRIBUTE_UNUSED;
687 asection *sec;
688 const Elf_Internal_Rela *relocs;
690 Elf_Internal_Shdr *symtab_hdr;
691 struct elf_link_hash_entry **sym_hashes;
692 bfd_signed_vma *local_got_refcounts;
693 const Elf_Internal_Rela *rel, *relend;
694 unsigned long r_symndx;
695 struct elf_link_hash_entry *h;
696 bfd *dynobj;
697 asection *sgot;
698 asection *srelgot;
700 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
701 sym_hashes = elf_sym_hashes (abfd);
702 local_got_refcounts = elf_local_got_refcounts (abfd);
704 dynobj = elf_hash_table (info)->dynobj;
705 if (dynobj == NULL)
706 return true;
708 sgot = bfd_get_section_by_name (dynobj, ".got");
709 srelgot = bfd_get_section_by_name (dynobj, ".rela.got");
711 relend = relocs + sec->reloc_count;
712 for (rel = relocs; rel < relend; rel++)
713 switch (ELF64_R_TYPE (rel->r_info))
715 case R_X86_64_GOT32:
716 case R_X86_64_GOTPCREL:
717 r_symndx = ELF64_R_SYM (rel->r_info);
718 if (r_symndx >= symtab_hdr->sh_info)
720 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
721 if (h->got.refcount > 0)
723 h->got.refcount -= 1;
724 if (h->got.refcount == 0)
726 sgot->_raw_size -= GOT_ENTRY_SIZE;
727 srelgot->_raw_size -= sizeof (Elf64_External_Rela);
731 else if (local_got_refcounts != NULL)
733 if (local_got_refcounts[r_symndx] > 0)
735 local_got_refcounts[r_symndx] -= 1;
736 if (local_got_refcounts[r_symndx] == 0)
738 sgot->_raw_size -= GOT_ENTRY_SIZE;
739 if (info->shared)
740 srelgot->_raw_size -= sizeof (Elf64_External_Rela);
744 break;
746 case R_X86_64_PLT32:
747 r_symndx = ELF64_R_SYM (rel->r_info);
748 if (r_symndx >= symtab_hdr->sh_info)
750 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
751 if (h->plt.refcount > 0)
752 h->plt.refcount -= 1;
754 break;
756 default:
757 break;
760 return true;
763 /* Adjust a symbol defined by a dynamic object and referenced by a
764 regular object. The current definition is in some section of the
765 dynamic object, but we're not including those sections. We have to
766 change the definition to something the rest of the link can
767 understand. */
769 static boolean
770 elf64_x86_64_adjust_dynamic_symbol (info, h)
771 struct bfd_link_info *info;
772 struct elf_link_hash_entry *h;
774 bfd *dynobj;
775 asection *s;
776 unsigned int power_of_two;
778 dynobj = elf_hash_table (info)->dynobj;
780 /* Make sure we know what is going on here. */
781 BFD_ASSERT (dynobj != NULL
782 && ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
783 || h->weakdef != NULL
784 || ((h->elf_link_hash_flags
785 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
786 && (h->elf_link_hash_flags
787 & ELF_LINK_HASH_REF_REGULAR) != 0
788 && (h->elf_link_hash_flags
789 & ELF_LINK_HASH_DEF_REGULAR) == 0)));
791 /* If this is a function, put it in the procedure linkage table. We
792 will fill in the contents of the procedure linkage table later,
793 when we know the address of the .got section. */
794 if (h->type == STT_FUNC
795 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
797 if ((! info->shared
798 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
799 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0)
800 || (info->shared && h->plt.refcount <= 0))
802 /* This case can occur if we saw a PLT32 reloc in an input
803 file, but the symbol was never referred to by a dynamic
804 object, or if all references were garbage collected. In
805 such a case, we don't actually need to build a procedure
806 linkage table, and we can just do a PC32 reloc instead. */
807 h->plt.offset = (bfd_vma) -1;
808 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
809 return true;
812 /* Make sure this symbol is output as a dynamic symbol. */
813 if (h->dynindx == -1)
815 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
816 return false;
819 s = bfd_get_section_by_name (dynobj, ".plt");
820 BFD_ASSERT (s != NULL);
822 /* If this is the first .plt entry, make room for the special
823 first entry. */
824 if (s->_raw_size == 0)
825 s->_raw_size = PLT_ENTRY_SIZE;
827 /* If this symbol is not defined in a regular file, and we are
828 not generating a shared library, then set the symbol to this
829 location in the .plt. This is required to make function
830 pointers compare as equal between the normal executable and
831 the shared library. */
832 if (! info->shared
833 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
835 h->root.u.def.section = s;
836 h->root.u.def.value = s->_raw_size;
839 h->plt.offset = s->_raw_size;
841 /* Make room for this entry. */
842 s->_raw_size += PLT_ENTRY_SIZE;
844 /* We also need to make an entry in the .got.plt section, which
845 will be placed in the .got section by the linker script. */
846 s = bfd_get_section_by_name (dynobj, ".got.plt");
847 BFD_ASSERT (s != NULL);
848 s->_raw_size += GOT_ENTRY_SIZE;
850 /* We also need to make an entry in the .rela.plt section. */
851 s = bfd_get_section_by_name (dynobj, ".rela.plt");
852 BFD_ASSERT (s != NULL);
853 s->_raw_size += sizeof (Elf64_External_Rela);
855 return true;
857 else
858 h->plt.offset = (bfd_vma) -1;
860 /* If this is a weak symbol, and there is a real definition, the
861 processor independent code will have arranged for us to see the
862 real definition first, and we can just use the same value. */
863 if (h->weakdef != NULL)
865 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
866 || h->weakdef->root.type == bfd_link_hash_defweak);
867 h->root.u.def.section = h->weakdef->root.u.def.section;
868 h->root.u.def.value = h->weakdef->root.u.def.value;
869 return true;
872 /* This is a reference to a symbol defined by a dynamic object which
873 is not a function. */
875 /* If we are creating a shared library, we must presume that the
876 only references to the symbol are via the global offset table.
877 For such cases we need not do anything here; the relocations will
878 be handled correctly by relocate_section. */
879 if (info->shared)
880 return true;
882 /* If there are no references to this symbol that do not use the
883 GOT, we don't need to generate a copy reloc. */
884 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0)
885 return true;
887 /* We must allocate the symbol in our .dynbss section, which will
888 become part of the .bss section of the executable. There will be
889 an entry for this symbol in the .dynsym section. The dynamic
890 object will contain position independent code, so all references
891 from the dynamic object to this symbol will go through the global
892 offset table. The dynamic linker will use the .dynsym entry to
893 determine the address it must put in the global offset table, so
894 both the dynamic object and the regular object will refer to the
895 same memory location for the variable. */
897 s = bfd_get_section_by_name (dynobj, ".dynbss");
898 BFD_ASSERT (s != NULL);
900 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
901 to copy the initial value out of the dynamic object and into the
902 runtime process image. We need to remember the offset into the
903 .rela.bss section we are going to use. */
904 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
906 asection *srel;
908 srel = bfd_get_section_by_name (dynobj, ".rela.bss");
909 BFD_ASSERT (srel != NULL);
910 srel->_raw_size += sizeof (Elf64_External_Rela);
911 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
914 /* We need to figure out the alignment required for this symbol. I
915 have no idea how ELF linkers handle this. 16-bytes is the size
916 of the largest type that requires hard alignment -- long double. */
917 /* FIXME: This is VERY ugly. Should be fixed for all architectures using
918 this construct. */
919 power_of_two = bfd_log2 (h->size);
920 if (power_of_two > 4)
921 power_of_two = 4;
923 /* Apply the required alignment. */
924 s->_raw_size = BFD_ALIGN (s->_raw_size, (bfd_size_type) (1 << power_of_two));
925 if (power_of_two > bfd_get_section_alignment (dynobj, s))
927 if (! bfd_set_section_alignment (dynobj, s, power_of_two))
928 return false;
931 /* Define the symbol as being at this point in the section. */
932 h->root.u.def.section = s;
933 h->root.u.def.value = s->_raw_size;
935 /* Increment the section size to make room for the symbol. */
936 s->_raw_size += h->size;
938 return true;
941 /* Set the sizes of the dynamic sections. */
943 static boolean
944 elf64_x86_64_size_dynamic_sections (output_bfd, info)
945 bfd *output_bfd ATTRIBUTE_UNUSED;
946 struct bfd_link_info *info;
948 bfd *dynobj;
949 asection *s;
950 boolean plt;
951 boolean relocs;
953 dynobj = elf_hash_table (info)->dynobj;
954 BFD_ASSERT (dynobj != NULL);
956 if (elf_hash_table (info)->dynamic_sections_created)
958 /* Set the contents of the .interp section to the interpreter. */
959 if (! info->shared)
961 s = bfd_get_section_by_name (dynobj, ".interp");
962 BFD_ASSERT (s != NULL);
963 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
964 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
967 else
969 /* We may have created entries in the .rela.got section.
970 However, if we are not creating the dynamic sections, we will
971 not actually use these entries. Reset the size of .rela.got,
972 which will cause it to get stripped from the output file
973 below. */
974 s = bfd_get_section_by_name (dynobj, ".rela.got");
975 if (s != NULL)
976 s->_raw_size = 0;
979 /* If this is a -Bsymbolic shared link, then we need to discard all
980 PC relative relocs against symbols defined in a regular object.
981 We allocated space for them in the check_relocs routine, but we
982 will not fill them in in the relocate_section routine. */
983 if (info->shared)
984 elf64_x86_64_link_hash_traverse (elf64_x86_64_hash_table (info),
985 elf64_x86_64_discard_copies,
986 (PTR) info);
988 /* The check_relocs and adjust_dynamic_symbol entry points have
989 determined the sizes of the various dynamic sections. Allocate
990 memory for them. */
991 plt = relocs = false;
992 for (s = dynobj->sections; s != NULL; s = s->next)
994 const char *name;
995 boolean strip;
997 if ((s->flags & SEC_LINKER_CREATED) == 0)
998 continue;
1000 /* It's OK to base decisions on the section name, because none
1001 of the dynobj section names depend upon the input files. */
1002 name = bfd_get_section_name (dynobj, s);
1004 strip = false;
1005 if (strcmp (name, ".plt") == 0)
1007 if (s->_raw_size == 0)
1009 /* Strip this section if we don't need it; see the
1010 comment below. */
1011 strip = true;
1013 else
1015 /* Remember whether there is a PLT. */
1016 plt = true;
1019 else if (strncmp (name, ".rela", 5) == 0)
1021 if (s->_raw_size == 0)
1023 /* If we don't need this section, strip it from the
1024 output file. This is mostly to handle .rela.bss and
1025 .rela.plt. We must create both sections in
1026 create_dynamic_sections, because they must be created
1027 before the linker maps input sections to output
1028 sections. The linker does that before
1029 adjust_dynamic_symbol is called, and it is that
1030 function which decides whether anything needs to go
1031 into these sections. */
1032 strip = true;
1034 else
1036 if (strcmp (name, ".rela.plt") != 0)
1037 relocs = true;
1039 /* We use the reloc_count field as a counter if we need
1040 to copy relocs into the output file. */
1041 s->reloc_count = 0;
1044 else if (strncmp (name, ".got", 4) != 0)
1046 /* It's not one of our sections, so don't allocate space. */
1047 continue;
1050 if (strip)
1052 _bfd_strip_section_from_output (info, s);
1053 continue;
1056 /* Allocate memory for the section contents. We use bfd_zalloc
1057 here in case unused entries are not reclaimed before the
1058 section's contents are written out. This should not happen,
1059 but this way if it does, we get a R_X86_64_NONE reloc instead
1060 of garbage. */
1061 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
1062 if (s->contents == NULL && s->_raw_size != 0)
1063 return false;
1066 if (elf_hash_table (info)->dynamic_sections_created)
1068 /* Add some entries to the .dynamic section. We fill in the
1069 values later, in elf64_x86_64_finish_dynamic_sections, but we
1070 must add the entries now so that we get the correct size for
1071 the .dynamic section. The DT_DEBUG entry is filled in by the
1072 dynamic linker and used by the debugger. */
1073 #define add_dynamic_entry(TAG, VAL) \
1074 bfd_elf64_add_dynamic_entry (info, (bfd_vma) (TAG), (bfd_vma) (VAL))
1076 if (! info->shared)
1078 if (!add_dynamic_entry (DT_DEBUG, 0))
1079 return false;
1082 if (plt)
1084 if (!add_dynamic_entry (DT_PLTGOT, 0)
1085 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1086 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1087 || !add_dynamic_entry (DT_JMPREL, 0))
1088 return false;
1091 if (relocs)
1093 if (!add_dynamic_entry (DT_RELA, 0)
1094 || !add_dynamic_entry (DT_RELASZ, 0)
1095 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
1096 return false;
1099 if ((info->flags & DF_TEXTREL) != 0)
1101 if (!add_dynamic_entry (DT_TEXTREL, 0))
1102 return false;
1105 #undef add_dynamic_entry
1107 return true;
1110 /* This function is called via elf64_x86_64_link_hash_traverse if we are
1111 creating a shared object. In the -Bsymbolic case, it discards the
1112 space allocated to copy PC relative relocs against symbols which
1113 are defined in regular objects. For the normal non-symbolic case,
1114 we also discard space for relocs that have become local due to
1115 symbol visibility changes. We allocated space for them in the
1116 check_relocs routine, but we won't fill them in in the
1117 relocate_section routine. */
1119 static boolean
1120 elf64_x86_64_discard_copies (h, inf)
1121 struct elf64_x86_64_link_hash_entry *h;
1122 PTR inf;
1124 struct elf64_x86_64_pcrel_relocs_copied *s;
1125 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1127 /* If a symbol has been forced local or we have found a regular
1128 definition for the symbolic link case, then we won't be needing
1129 any relocs. */
1130 if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
1131 && ((h->root.elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0
1132 || info->symbolic))
1134 for (s = h->pcrel_relocs_copied; s != NULL; s = s->next)
1135 s->section->_raw_size -= s->count * sizeof (Elf64_External_Rela);
1138 return true;
1141 /* Relocate an x86_64 ELF section. */
1143 static boolean
1144 elf64_x86_64_relocate_section (output_bfd, info, input_bfd, input_section,
1145 contents, relocs, local_syms, local_sections)
1146 bfd *output_bfd;
1147 struct bfd_link_info *info;
1148 bfd *input_bfd;
1149 asection *input_section;
1150 bfd_byte *contents;
1151 Elf_Internal_Rela *relocs;
1152 Elf_Internal_Sym *local_syms;
1153 asection **local_sections;
1155 bfd *dynobj;
1156 Elf_Internal_Shdr *symtab_hdr;
1157 struct elf_link_hash_entry **sym_hashes;
1158 bfd_vma *local_got_offsets;
1159 asection *sgot;
1160 asection *splt;
1161 asection *sreloc;
1162 Elf_Internal_Rela *rela;
1163 Elf_Internal_Rela *relend;
1165 dynobj = elf_hash_table (info)->dynobj;
1166 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1167 sym_hashes = elf_sym_hashes (input_bfd);
1168 local_got_offsets = elf_local_got_offsets (input_bfd);
1170 sreloc = splt = sgot = NULL;
1171 if (dynobj != NULL)
1173 splt = bfd_get_section_by_name (dynobj, ".plt");
1174 sgot = bfd_get_section_by_name (dynobj, ".got");
1177 rela = relocs;
1178 relend = relocs + input_section->reloc_count;
1179 for (; rela < relend; rela++)
1181 int r_type;
1182 reloc_howto_type *howto;
1183 unsigned long r_symndx;
1184 struct elf_link_hash_entry *h;
1185 Elf_Internal_Sym *sym;
1186 asection *sec;
1187 bfd_vma relocation;
1188 bfd_reloc_status_type r;
1189 unsigned int indx;
1191 r_type = ELF64_R_TYPE (rela->r_info);
1192 if (r_type == (int) R_X86_64_GNU_VTINHERIT
1193 || r_type == (int) R_X86_64_GNU_VTENTRY)
1194 continue;
1196 if ((indx = (unsigned) r_type) >= R_X86_64_max)
1198 bfd_set_error (bfd_error_bad_value);
1199 return false;
1201 howto = x86_64_elf_howto_table + indx;
1203 r_symndx = ELF64_R_SYM (rela->r_info);
1205 if (info->relocateable)
1207 /* This is a relocateable link. We don't have to change
1208 anything, unless the reloc is against a section symbol,
1209 in which case we have to adjust according to where the
1210 section symbol winds up in the output section. */
1211 if (r_symndx < symtab_hdr->sh_info)
1213 sym = local_syms + r_symndx;
1214 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
1216 sec = local_sections[r_symndx];
1217 rela->r_addend += sec->output_offset + sym->st_value;
1221 continue;
1224 /* This is a final link. */
1225 h = NULL;
1226 sym = NULL;
1227 sec = NULL;
1228 if (r_symndx < symtab_hdr->sh_info)
1230 sym = local_syms + r_symndx;
1231 sec = local_sections[r_symndx];
1232 relocation = (sec->output_section->vma
1233 + sec->output_offset
1234 + sym->st_value);
1236 else
1238 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1239 while (h->root.type == bfd_link_hash_indirect
1240 || h->root.type == bfd_link_hash_warning)
1241 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1242 if (h->root.type == bfd_link_hash_defined
1243 || h->root.type == bfd_link_hash_defweak)
1245 sec = h->root.u.def.section;
1246 if ((r_type == R_X86_64_PLT32
1247 && splt != NULL
1248 && h->plt.offset != (bfd_vma) -1)
1249 || ((r_type == R_X86_64_GOT32 || r_type == R_X86_64_GOTPCREL)
1250 && elf_hash_table (info)->dynamic_sections_created
1251 && (!info->shared
1252 || (! info->symbolic && h->dynindx != -1)
1253 || (h->elf_link_hash_flags
1254 & ELF_LINK_HASH_DEF_REGULAR) == 0))
1255 || (info->shared
1256 && ((! info->symbolic && h->dynindx != -1)
1257 || (h->elf_link_hash_flags
1258 & ELF_LINK_HASH_DEF_REGULAR) == 0)
1259 && (r_type == R_X86_64_8
1260 || r_type == R_X86_64_16
1261 || r_type == R_X86_64_32
1262 || r_type == R_X86_64_64
1263 || r_type == R_X86_64_PC8
1264 || r_type == R_X86_64_PC16
1265 || r_type == R_X86_64_PC32)
1266 && ((input_section->flags & SEC_ALLOC) != 0
1267 /* DWARF will emit R_X86_64_32 relocations in its
1268 sections against symbols defined externally
1269 in shared libraries. We can't do anything
1270 with them here. */
1271 || ((input_section->flags & SEC_DEBUGGING) != 0
1272 && (h->elf_link_hash_flags
1273 & ELF_LINK_HASH_DEF_DYNAMIC) != 0))))
1275 /* In these cases, we don't need the relocation
1276 value. We check specially because in some
1277 obscure cases sec->output_section will be NULL. */
1278 relocation = 0;
1280 else if (sec->output_section == NULL)
1282 (*_bfd_error_handler)
1283 (_("%s: warning: unresolvable relocation against symbol `%s' from %s section"),
1284 bfd_archive_filename (input_bfd), h->root.root.string,
1285 bfd_get_section_name (input_bfd, input_section));
1286 relocation = 0;
1288 else
1289 relocation = (h->root.u.def.value
1290 + sec->output_section->vma
1291 + sec->output_offset);
1293 else if (h->root.type == bfd_link_hash_undefweak)
1294 relocation = 0;
1295 else if (info->shared
1296 && (!info->symbolic || info->allow_shlib_undefined)
1297 && !info->no_undefined
1298 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
1299 relocation = 0;
1300 else
1302 if (! ((*info->callbacks->undefined_symbol)
1303 (info, h->root.root.string, input_bfd,
1304 input_section, rela->r_offset,
1305 (!info->shared || info->no_undefined
1306 || ELF_ST_VISIBILITY (h->other)))))
1307 return false;
1308 relocation = 0;
1312 /* When generating a shared object, the relocations handled here are
1313 copied into the output file to be resolved at run time. */
1314 switch (r_type)
1316 case R_X86_64_GOT32:
1317 /* Relocation is to the entry for this symbol in the global
1318 offset table. */
1319 case R_X86_64_GOTPCREL:
1320 /* Use global offset table as symbol value. */
1321 BFD_ASSERT (sgot != NULL);
1323 if (h != NULL)
1325 bfd_vma off = h->got.offset;
1326 BFD_ASSERT (off != (bfd_vma) -1);
1328 if (! elf_hash_table (info)->dynamic_sections_created
1329 || (info->shared
1330 && (info->symbolic || h->dynindx == -1)
1331 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1333 /* This is actually a static link, or it is a -Bsymbolic
1334 link and the symbol is defined locally, or the symbol
1335 was forced to be local because of a version file. We
1336 must initialize this entry in the global offset table.
1337 Since the offset must always be a multiple of 8, we
1338 use the least significant bit to record whether we
1339 have initialized it already.
1341 When doing a dynamic link, we create a .rela.got
1342 relocation entry to initialize the value. This is
1343 done in the finish_dynamic_symbol routine. */
1344 if ((off & 1) != 0)
1345 off &= ~1;
1346 else
1348 bfd_put_64 (output_bfd, relocation,
1349 sgot->contents + off);
1350 h->got.offset |= 1;
1353 if (r_type == R_X86_64_GOTPCREL)
1354 relocation = sgot->output_section->vma + sgot->output_offset + off;
1355 else
1356 relocation = sgot->output_offset + off;
1358 else
1360 bfd_vma off;
1362 BFD_ASSERT (local_got_offsets != NULL
1363 && local_got_offsets[r_symndx] != (bfd_vma) -1);
1365 off = local_got_offsets[r_symndx];
1367 /* The offset must always be a multiple of 8. We use
1368 the least significant bit to record whether we have
1369 already generated the necessary reloc. */
1370 if ((off & 1) != 0)
1371 off &= ~1;
1372 else
1374 bfd_put_64 (output_bfd, relocation, sgot->contents + off);
1376 if (info->shared)
1378 asection *srelgot;
1379 Elf_Internal_Rela outrel;
1381 /* We need to generate a R_X86_64_RELATIVE reloc
1382 for the dynamic linker. */
1383 srelgot = bfd_get_section_by_name (dynobj, ".rela.got");
1384 BFD_ASSERT (srelgot != NULL);
1386 outrel.r_offset = (sgot->output_section->vma
1387 + sgot->output_offset
1388 + off);
1389 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
1390 outrel.r_addend = relocation;
1391 bfd_elf64_swap_reloca_out (output_bfd, &outrel,
1392 (((Elf64_External_Rela *)
1393 srelgot->contents)
1394 + srelgot->reloc_count));
1395 ++srelgot->reloc_count;
1398 local_got_offsets[r_symndx] |= 1;
1401 if (r_type == R_X86_64_GOTPCREL)
1402 relocation = sgot->output_section->vma + sgot->output_offset + off;
1403 else
1404 relocation = sgot->output_offset + off;
1407 break;
1409 case R_X86_64_PLT32:
1410 /* Relocation is to the entry for this symbol in the
1411 procedure linkage table. */
1413 /* Resolve a PLT32 reloc against a local symbol directly,
1414 without using the procedure linkage table. */
1415 if (h == NULL)
1416 break;
1418 if (h->plt.offset == (bfd_vma) -1 || splt == NULL)
1420 /* We didn't make a PLT entry for this symbol. This
1421 happens when statically linking PIC code, or when
1422 using -Bsymbolic. */
1423 break;
1426 relocation = (splt->output_section->vma
1427 + splt->output_offset
1428 + h->plt.offset);
1429 break;
1431 case R_X86_64_PC8:
1432 case R_X86_64_PC16:
1433 case R_X86_64_PC32:
1434 if (h == NULL || h->dynindx == -1
1435 || (info->symbolic
1436 && h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
1437 break;
1438 /* Fall through. */
1439 case R_X86_64_8:
1440 case R_X86_64_16:
1441 case R_X86_64_32:
1442 case R_X86_64_64:
1443 /* FIXME: The ABI says the linker should make sure the value is
1444 the same when it's zeroextended to 64 bit. */
1445 if (info->shared
1446 && r_symndx != 0
1447 && (input_section->flags & SEC_ALLOC) != 0)
1449 Elf_Internal_Rela outrel;
1450 boolean skip, relocate;
1452 /* When generating a shared object, these relocations
1453 are copied into the output file to be resolved at run
1454 time. */
1456 if (sreloc == NULL)
1458 const char *name;
1460 name = (bfd_elf_string_from_elf_section
1461 (input_bfd,
1462 elf_elfheader (input_bfd)->e_shstrndx,
1463 elf_section_data (input_section)->rel_hdr.sh_name));
1464 if (name == NULL)
1465 return false;
1467 BFD_ASSERT (strncmp (name, ".rela", 5) == 0
1468 && strcmp (bfd_get_section_name (input_bfd,
1469 input_section),
1470 name + 5) == 0);
1472 sreloc = bfd_get_section_by_name (dynobj, name);
1473 BFD_ASSERT (sreloc != NULL);
1476 skip = false;
1478 if (elf_section_data (input_section)->stab_info == NULL)
1479 outrel.r_offset = rela->r_offset;
1480 else
1482 bfd_vma off;
1484 off = (_bfd_stab_section_offset
1485 (output_bfd, &elf_hash_table (info)->stab_info,
1486 input_section,
1487 &elf_section_data (input_section)->stab_info,
1488 rela->r_offset));
1489 if (off == (bfd_vma) -1)
1490 skip = true;
1491 outrel.r_offset = off;
1494 outrel.r_offset += (input_section->output_section->vma
1495 + input_section->output_offset);
1497 if (skip)
1499 memset (&outrel, 0, sizeof outrel);
1500 relocate = false;
1502 /* h->dynindx may be -1 if this symbol was marked to
1503 become local. */
1504 else if (h != NULL
1505 && ((! info->symbolic && h->dynindx != -1)
1506 || (h->elf_link_hash_flags
1507 & ELF_LINK_HASH_DEF_REGULAR) == 0))
1509 BFD_ASSERT (h->dynindx != -1);
1510 relocate = false;
1511 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
1512 outrel.r_addend = relocation + rela->r_addend;
1514 else
1516 if (r_type == R_X86_64_64)
1518 relocate = true;
1519 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
1520 outrel.r_addend = relocation + rela->r_addend;
1522 else
1524 long sindx;
1526 if (h == NULL)
1527 sec = local_sections[r_symndx];
1528 else
1530 BFD_ASSERT (h->root.type == bfd_link_hash_defined
1531 || (h->root.type
1532 == bfd_link_hash_defweak));
1533 sec = h->root.u.def.section;
1535 if (sec != NULL && bfd_is_abs_section (sec))
1536 sindx = 0;
1537 else if (sec == NULL || sec->owner == NULL)
1539 bfd_set_error (bfd_error_bad_value);
1540 return false;
1542 else
1544 asection *osec;
1546 osec = sec->output_section;
1547 sindx = elf_section_data (osec)->dynindx;
1548 BFD_ASSERT (sindx > 0);
1551 relocate = false;
1552 outrel.r_info = ELF64_R_INFO (sindx, r_type);
1553 outrel.r_addend = relocation + rela->r_addend;
1558 bfd_elf64_swap_reloca_out (output_bfd, &outrel,
1559 (((Elf64_External_Rela *)
1560 sreloc->contents)
1561 + sreloc->reloc_count));
1562 ++sreloc->reloc_count;
1564 /* If this reloc is against an external symbol, we do
1565 not want to fiddle with the addend. Otherwise, we
1566 need to include the symbol value so that it becomes
1567 an addend for the dynamic reloc. */
1568 if (! relocate)
1569 continue;
1572 break;
1574 default:
1575 break;
1578 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
1579 contents, rela->r_offset,
1580 relocation, rela->r_addend);
1582 if (r != bfd_reloc_ok)
1584 switch (r)
1586 default:
1587 case bfd_reloc_outofrange:
1588 abort ();
1589 case bfd_reloc_overflow:
1591 const char *name;
1593 if (h != NULL)
1594 name = h->root.root.string;
1595 else
1597 name = bfd_elf_string_from_elf_section (input_bfd,
1598 symtab_hdr->sh_link,
1599 sym->st_name);
1600 if (name == NULL)
1601 return false;
1602 if (*name == '\0')
1603 name = bfd_section_name (input_bfd, sec);
1605 if (! ((*info->callbacks->reloc_overflow)
1606 (info, name, howto->name, (bfd_vma) 0,
1607 input_bfd, input_section, rela->r_offset)))
1608 return false;
1610 break;
1615 return true;
1618 /* Finish up dynamic symbol handling. We set the contents of various
1619 dynamic sections here. */
1621 static boolean
1622 elf64_x86_64_finish_dynamic_symbol (output_bfd, info, h, sym)
1623 bfd *output_bfd;
1624 struct bfd_link_info *info;
1625 struct elf_link_hash_entry *h;
1626 Elf_Internal_Sym *sym;
1628 bfd *dynobj;
1630 dynobj = elf_hash_table (info)->dynobj;
1632 if (h->plt.offset != (bfd_vma) -1)
1634 asection *splt;
1635 asection *sgot;
1636 asection *srela;
1637 bfd_vma plt_index;
1638 bfd_vma got_offset;
1639 Elf_Internal_Rela rela;
1641 /* This symbol has an entry in the procedure linkage table. Set
1642 it up. */
1644 BFD_ASSERT (h->dynindx != -1);
1646 splt = bfd_get_section_by_name (dynobj, ".plt");
1647 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
1648 srela = bfd_get_section_by_name (dynobj, ".rela.plt");
1649 BFD_ASSERT (splt != NULL && sgot != NULL && srela != NULL);
1651 /* Get the index in the procedure linkage table which
1652 corresponds to this symbol. This is the index of this symbol
1653 in all the symbols for which we are making plt entries. The
1654 first entry in the procedure linkage table is reserved. */
1655 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
1657 /* Get the offset into the .got table of the entry that
1658 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
1659 bytes. The first three are reserved for the dynamic linker. */
1660 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
1662 /* Fill in the entry in the procedure linkage table. */
1663 memcpy (splt->contents + h->plt.offset, elf64_x86_64_plt_entry,
1664 PLT_ENTRY_SIZE);
1666 /* Insert the relocation positions of the plt section. The magic
1667 numbers at the end of the statements are the positions of the
1668 relocations in the plt section. */
1669 /* Put offset for jmp *name@GOTPCREL(%rip), since the
1670 instruction uses 6 bytes, subtract this value. */
1671 bfd_put_32 (output_bfd,
1672 (sgot->output_section->vma
1673 + sgot->output_offset
1674 + got_offset
1675 - splt->output_section->vma
1676 - splt->output_offset
1677 - h->plt.offset
1678 - 6),
1679 splt->contents + h->plt.offset + 2);
1680 /* Put relocation index. */
1681 bfd_put_32 (output_bfd, plt_index,
1682 splt->contents + h->plt.offset + 7);
1683 /* Put offset for jmp .PLT0. */
1684 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
1685 splt->contents + h->plt.offset + 12);
1687 /* Fill in the entry in the global offset table, initially this
1688 points to the pushq instruction in the PLT which is at offset 6. */
1689 bfd_put_64 (output_bfd, (splt->output_section->vma + splt->output_offset
1690 + h->plt.offset + 6),
1691 sgot->contents + got_offset);
1693 /* Fill in the entry in the .rela.plt section. */
1694 rela.r_offset = (sgot->output_section->vma
1695 + sgot->output_offset
1696 + got_offset);
1697 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
1698 rela.r_addend = 0;
1699 bfd_elf64_swap_reloca_out (output_bfd, &rela,
1700 ((Elf64_External_Rela *) srela->contents
1701 + plt_index));
1703 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1705 /* Mark the symbol as undefined, rather than as defined in
1706 the .plt section. Leave the value alone. */
1707 sym->st_shndx = SHN_UNDEF;
1708 /* If the symbol is weak, we do need to clear the value.
1709 Otherwise, the PLT entry would provide a definition for
1710 the symbol even if the symbol wasn't defined anywhere,
1711 and so the symbol would never be NULL. */
1712 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK)
1713 == 0)
1714 sym->st_value = 0;
1718 if (h->got.offset != (bfd_vma) -1)
1720 asection *sgot;
1721 asection *srela;
1722 Elf_Internal_Rela rela;
1724 /* This symbol has an entry in the global offset table. Set it
1725 up. */
1727 sgot = bfd_get_section_by_name (dynobj, ".got");
1728 srela = bfd_get_section_by_name (dynobj, ".rela.got");
1729 BFD_ASSERT (sgot != NULL && srela != NULL);
1731 rela.r_offset = (sgot->output_section->vma
1732 + sgot->output_offset
1733 + (h->got.offset &~ (bfd_vma) 1));
1735 /* If this is a static link, or it is a -Bsymbolic link and the
1736 symbol is defined locally or was forced to be local because
1737 of a version file, we just want to emit a RELATIVE reloc.
1738 The entry in the global offset table will already have been
1739 initialized in the relocate_section function. */
1740 if (! elf_hash_table (info)->dynamic_sections_created
1741 || (info->shared
1742 && (info->symbolic || h->dynindx == -1)
1743 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1745 BFD_ASSERT((h->got.offset & 1) != 0);
1746 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
1747 rela.r_addend = (h->root.u.def.value
1748 + h->root.u.def.section->output_section->vma
1749 + h->root.u.def.section->output_offset);
1751 else
1753 BFD_ASSERT((h->got.offset & 1) == 0);
1754 bfd_put_64 (output_bfd, (bfd_vma) 0, sgot->contents + h->got.offset);
1755 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
1756 rela.r_addend = 0;
1759 bfd_elf64_swap_reloca_out (output_bfd, &rela,
1760 ((Elf64_External_Rela *) srela->contents
1761 + srela->reloc_count));
1762 ++srela->reloc_count;
1765 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
1767 asection *s;
1768 Elf_Internal_Rela rela;
1770 /* This symbol needs a copy reloc. Set it up. */
1772 BFD_ASSERT (h->dynindx != -1
1773 && (h->root.type == bfd_link_hash_defined
1774 || h->root.type == bfd_link_hash_defweak));
1776 s = bfd_get_section_by_name (h->root.u.def.section->owner,
1777 ".rela.bss");
1778 BFD_ASSERT (s != NULL);
1780 rela.r_offset = (h->root.u.def.value
1781 + h->root.u.def.section->output_section->vma
1782 + h->root.u.def.section->output_offset);
1783 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
1784 rela.r_addend = 0;
1785 bfd_elf64_swap_reloca_out (output_bfd, &rela,
1786 ((Elf64_External_Rela *) s->contents
1787 + s->reloc_count));
1788 ++s->reloc_count;
1791 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
1792 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
1793 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
1794 sym->st_shndx = SHN_ABS;
1796 return true;
1799 /* Finish up the dynamic sections. */
1801 static boolean
1802 elf64_x86_64_finish_dynamic_sections (output_bfd, info)
1803 bfd *output_bfd;
1804 struct bfd_link_info *info;
1806 bfd *dynobj;
1807 asection *sdyn;
1808 asection *sgot;
1810 dynobj = elf_hash_table (info)->dynobj;
1812 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
1813 BFD_ASSERT (sgot != NULL);
1814 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
1816 if (elf_hash_table (info)->dynamic_sections_created)
1818 asection *splt;
1819 Elf64_External_Dyn *dyncon, *dynconend;
1821 BFD_ASSERT (sdyn != NULL);
1823 dyncon = (Elf64_External_Dyn *) sdyn->contents;
1824 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
1825 for (; dyncon < dynconend; dyncon++)
1827 Elf_Internal_Dyn dyn;
1828 const char *name;
1829 asection *s;
1831 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
1833 switch (dyn.d_tag)
1835 default:
1836 continue;
1838 case DT_PLTGOT:
1839 name = ".got";
1840 goto get_vma;
1842 case DT_JMPREL:
1843 name = ".rela.plt";
1845 get_vma:
1846 s = bfd_get_section_by_name (output_bfd, name);
1847 BFD_ASSERT (s != NULL);
1848 dyn.d_un.d_ptr = s->vma;
1849 break;
1851 case DT_RELASZ:
1852 /* FIXME: This comment and code is from elf64-alpha.c: */
1853 /* My interpretation of the TIS v1.1 ELF document indicates
1854 that RELASZ should not include JMPREL. This is not what
1855 the rest of the BFD does. It is, however, what the
1856 glibc ld.so wants. Do this fixup here until we found
1857 out who is right. */
1858 s = bfd_get_section_by_name (output_bfd, ".rela.plt");
1859 if (s)
1861 /* Subtract JMPREL size from RELASZ. */
1862 dyn.d_un.d_val -=
1863 (s->_cooked_size ? s->_cooked_size : s->_raw_size);
1865 break;
1867 case DT_PLTRELSZ:
1868 s = bfd_get_section_by_name (output_bfd, ".rela.plt");
1869 BFD_ASSERT (s != NULL);
1870 dyn.d_un.d_val =
1871 (s->_cooked_size != 0 ? s->_cooked_size : s->_raw_size);
1872 break;
1874 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
1877 /* Initialize the contents of the .plt section. */
1878 splt = bfd_get_section_by_name (dynobj, ".plt");
1879 BFD_ASSERT (splt != NULL);
1880 if (splt->_raw_size > 0)
1882 /* Fill in the first entry in the procedure linkage table. */
1883 memcpy (splt->contents, elf64_x86_64_plt0_entry, PLT_ENTRY_SIZE);
1884 /* Add offset for pushq GOT+8(%rip), since the instruction
1885 uses 6 bytes subtract this value. */
1886 bfd_put_32 (output_bfd,
1887 (sgot->output_section->vma
1888 + sgot->output_offset
1890 - splt->output_section->vma
1891 - splt->output_offset
1892 - 6),
1893 splt->contents + 2);
1894 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
1895 the end of the instruction. */
1896 bfd_put_32 (output_bfd,
1897 (sgot->output_section->vma
1898 + sgot->output_offset
1899 + 16
1900 - splt->output_section->vma
1901 - splt->output_offset
1902 - 12),
1903 splt->contents + 8);
1907 elf_section_data (splt->output_section)->this_hdr.sh_entsize =
1908 PLT_ENTRY_SIZE;
1911 /* Set the first entry in the global offset table to the address of
1912 the dynamic section. */
1913 if (sgot->_raw_size > 0)
1915 if (sdyn == NULL)
1916 bfd_put_64 (output_bfd, (bfd_vma) 0, sgot->contents);
1917 else
1918 bfd_put_64 (output_bfd,
1919 sdyn->output_section->vma + sdyn->output_offset,
1920 sgot->contents);
1921 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
1922 bfd_put_64 (output_bfd, (bfd_vma) 0, sgot->contents + GOT_ENTRY_SIZE);
1923 bfd_put_64 (output_bfd, (bfd_vma) 0, sgot->contents + GOT_ENTRY_SIZE*2);
1926 elf_section_data (sgot->output_section)->this_hdr.sh_entsize =
1927 GOT_ENTRY_SIZE;
1929 return true;
1932 static enum elf_reloc_type_class
1933 elf64_x86_64_reloc_type_class (rela)
1934 const Elf_Internal_Rela *rela;
1936 switch ((int) ELF64_R_TYPE (rela->r_info))
1938 case R_X86_64_RELATIVE:
1939 return reloc_class_relative;
1940 case R_X86_64_JUMP_SLOT:
1941 return reloc_class_plt;
1942 case R_X86_64_COPY:
1943 return reloc_class_copy;
1944 default:
1945 return reloc_class_normal;
1949 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
1950 #define TARGET_LITTLE_NAME "elf64-x86-64"
1951 #define ELF_ARCH bfd_arch_i386
1952 #define ELF_MACHINE_CODE EM_X86_64
1953 #define ELF_MAXPAGESIZE 0x100000
1955 #define elf_backend_can_gc_sections 1
1956 #define elf_backend_can_refcount 1
1957 #define elf_backend_want_got_plt 1
1958 #define elf_backend_plt_readonly 1
1959 #define elf_backend_want_plt_sym 0
1960 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
1961 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
1963 #define elf_info_to_howto elf64_x86_64_info_to_howto
1965 #define bfd_elf64_bfd_final_link _bfd_elf64_gc_common_final_link
1966 #define bfd_elf64_bfd_link_hash_table_create \
1967 elf64_x86_64_link_hash_table_create
1968 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
1970 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
1971 #define elf_backend_check_relocs elf64_x86_64_check_relocs
1972 #define elf_backend_create_dynamic_sections _bfd_elf_create_dynamic_sections
1973 #define elf_backend_finish_dynamic_sections \
1974 elf64_x86_64_finish_dynamic_sections
1975 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
1976 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
1977 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
1978 #define elf_backend_relocate_section elf64_x86_64_relocate_section
1979 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
1980 #define elf_backend_object_p elf64_x86_64_elf_object_p
1981 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
1983 #include "elf64-target.h"