5ed6b518dbe170e276a3007299692b7fffe6cd52
[deliverable/binutils-gdb.git] / bfd / elf64-x86-64.c
1 /* X86-64 specific support for 64-bit ELF
2 Copyright 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
3 Contributed by Jan Hubicka <jh@suse.cz>.
4
5 This file is part of BFD, the Binary File Descriptor library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20
21 #include "bfd.h"
22 #include "sysdep.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #include "elf-bfd.h"
26
27 #include "elf/x86-64.h"
28
29 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
30 #define MINUS_ONE (~ (bfd_vma) 0)
31
32 /* The relocation "howto" table. Order of fields:
33 type, size, bitsize, pc_relative, complain_on_overflow,
34 special_function, name, partial_inplace, src_mask, dst_pack, pcrel_offset. */
35 static reloc_howto_type x86_64_elf_howto_table[] =
36 {
37 HOWTO(R_X86_64_NONE, 0, 0, 0, FALSE, 0, complain_overflow_dont,
38 bfd_elf_generic_reloc, "R_X86_64_NONE", FALSE, 0x00000000, 0x00000000,
39 FALSE),
40 HOWTO(R_X86_64_64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
41 bfd_elf_generic_reloc, "R_X86_64_64", FALSE, MINUS_ONE, MINUS_ONE,
42 FALSE),
43 HOWTO(R_X86_64_PC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
44 bfd_elf_generic_reloc, "R_X86_64_PC32", FALSE, 0xffffffff, 0xffffffff,
45 TRUE),
46 HOWTO(R_X86_64_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
47 bfd_elf_generic_reloc, "R_X86_64_GOT32", FALSE, 0xffffffff, 0xffffffff,
48 FALSE),
49 HOWTO(R_X86_64_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
50 bfd_elf_generic_reloc, "R_X86_64_PLT32", FALSE, 0xffffffff, 0xffffffff,
51 TRUE),
52 HOWTO(R_X86_64_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
53 bfd_elf_generic_reloc, "R_X86_64_COPY", FALSE, 0xffffffff, 0xffffffff,
54 FALSE),
55 HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
56 bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", FALSE, MINUS_ONE,
57 MINUS_ONE, FALSE),
58 HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
59 bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", FALSE, MINUS_ONE,
60 MINUS_ONE, FALSE),
61 HOWTO(R_X86_64_RELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
62 bfd_elf_generic_reloc, "R_X86_64_RELATIVE", FALSE, MINUS_ONE,
63 MINUS_ONE, FALSE),
64 HOWTO(R_X86_64_GOTPCREL, 0, 2, 32, TRUE, 0, complain_overflow_signed,
65 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", FALSE, 0xffffffff,
66 0xffffffff, TRUE),
67 HOWTO(R_X86_64_32, 0, 2, 32, FALSE, 0, complain_overflow_unsigned,
68 bfd_elf_generic_reloc, "R_X86_64_32", FALSE, 0xffffffff, 0xffffffff,
69 FALSE),
70 HOWTO(R_X86_64_32S, 0, 2, 32, FALSE, 0, complain_overflow_signed,
71 bfd_elf_generic_reloc, "R_X86_64_32S", FALSE, 0xffffffff, 0xffffffff,
72 FALSE),
73 HOWTO(R_X86_64_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
74 bfd_elf_generic_reloc, "R_X86_64_16", FALSE, 0xffff, 0xffff, FALSE),
75 HOWTO(R_X86_64_PC16,0, 1, 16, TRUE, 0, complain_overflow_bitfield,
76 bfd_elf_generic_reloc, "R_X86_64_PC16", FALSE, 0xffff, 0xffff, TRUE),
77 HOWTO(R_X86_64_8, 0, 0, 8, FALSE, 0, complain_overflow_signed,
78 bfd_elf_generic_reloc, "R_X86_64_8", FALSE, 0xff, 0xff, FALSE),
79 HOWTO(R_X86_64_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed,
80 bfd_elf_generic_reloc, "R_X86_64_PC8", FALSE, 0xff, 0xff, TRUE),
81 HOWTO(R_X86_64_DTPMOD64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
82 bfd_elf_generic_reloc, "R_X86_64_DTPMOD64", FALSE, MINUS_ONE,
83 MINUS_ONE, FALSE),
84 HOWTO(R_X86_64_DTPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
85 bfd_elf_generic_reloc, "R_X86_64_DTPOFF64", FALSE, MINUS_ONE,
86 MINUS_ONE, FALSE),
87 HOWTO(R_X86_64_TPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
88 bfd_elf_generic_reloc, "R_X86_64_TPOFF64", FALSE, MINUS_ONE,
89 MINUS_ONE, FALSE),
90 HOWTO(R_X86_64_TLSGD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
91 bfd_elf_generic_reloc, "R_X86_64_TLSGD", FALSE, 0xffffffff,
92 0xffffffff, TRUE),
93 HOWTO(R_X86_64_TLSLD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
94 bfd_elf_generic_reloc, "R_X86_64_TLSLD", FALSE, 0xffffffff,
95 0xffffffff, TRUE),
96 HOWTO(R_X86_64_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
97 bfd_elf_generic_reloc, "R_X86_64_DTPOFF32", FALSE, 0xffffffff,
98 0xffffffff, FALSE),
99 HOWTO(R_X86_64_GOTTPOFF, 0, 2, 32, TRUE, 0, complain_overflow_signed,
100 bfd_elf_generic_reloc, "R_X86_64_GOTTPOFF", FALSE, 0xffffffff,
101 0xffffffff, TRUE),
102 HOWTO(R_X86_64_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
103 bfd_elf_generic_reloc, "R_X86_64_TPOFF32", FALSE, 0xffffffff,
104 0xffffffff, FALSE),
105
106 /* GNU extension to record C++ vtable hierarchy. */
107 HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, FALSE, 0, complain_overflow_dont,
108 NULL, "R_X86_64_GNU_VTINHERIT", FALSE, 0, 0, FALSE),
109
110 /* GNU extension to record C++ vtable member usage. */
111 HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, FALSE, 0, complain_overflow_dont,
112 _bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", FALSE, 0, 0,
113 FALSE)
114 };
115
116 /* Map BFD relocs to the x86_64 elf relocs. */
117 struct elf_reloc_map
118 {
119 bfd_reloc_code_real_type bfd_reloc_val;
120 unsigned char elf_reloc_val;
121 };
122
123 static const struct elf_reloc_map x86_64_reloc_map[] =
124 {
125 { BFD_RELOC_NONE, R_X86_64_NONE, },
126 { BFD_RELOC_64, R_X86_64_64, },
127 { BFD_RELOC_32_PCREL, R_X86_64_PC32, },
128 { BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,},
129 { BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,},
130 { BFD_RELOC_X86_64_COPY, R_X86_64_COPY, },
131 { BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, },
132 { BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, },
133 { BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, },
134 { BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, },
135 { BFD_RELOC_32, R_X86_64_32, },
136 { BFD_RELOC_X86_64_32S, R_X86_64_32S, },
137 { BFD_RELOC_16, R_X86_64_16, },
138 { BFD_RELOC_16_PCREL, R_X86_64_PC16, },
139 { BFD_RELOC_8, R_X86_64_8, },
140 { BFD_RELOC_8_PCREL, R_X86_64_PC8, },
141 { BFD_RELOC_X86_64_DTPMOD64, R_X86_64_DTPMOD64, },
142 { BFD_RELOC_X86_64_DTPOFF64, R_X86_64_DTPOFF64, },
143 { BFD_RELOC_X86_64_TPOFF64, R_X86_64_TPOFF64, },
144 { BFD_RELOC_X86_64_TLSGD, R_X86_64_TLSGD, },
145 { BFD_RELOC_X86_64_TLSLD, R_X86_64_TLSLD, },
146 { BFD_RELOC_X86_64_DTPOFF32, R_X86_64_DTPOFF32, },
147 { BFD_RELOC_X86_64_GOTTPOFF, R_X86_64_GOTTPOFF, },
148 { BFD_RELOC_X86_64_TPOFF32, R_X86_64_TPOFF32, },
149 { BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
150 { BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
151 };
152
153 static reloc_howto_type *elf64_x86_64_reloc_type_lookup
154 PARAMS ((bfd *, bfd_reloc_code_real_type));
155 static void elf64_x86_64_info_to_howto
156 PARAMS ((bfd *, arelent *, Elf_Internal_Rela *));
157 static bfd_boolean elf64_x86_64_grok_prstatus
158 PARAMS ((bfd *, Elf_Internal_Note *));
159 static bfd_boolean elf64_x86_64_grok_psinfo
160 PARAMS ((bfd *, Elf_Internal_Note *));
161 static struct bfd_link_hash_table *elf64_x86_64_link_hash_table_create
162 PARAMS ((bfd *));
163 static int elf64_x86_64_tls_transition
164 PARAMS ((struct bfd_link_info *, int, int));
165 static bfd_boolean elf64_x86_64_mkobject
166 PARAMS((bfd *));
167 static bfd_boolean elf64_x86_64_elf_object_p PARAMS ((bfd *abfd));
168 static bfd_boolean create_got_section
169 PARAMS((bfd *, struct bfd_link_info *));
170 static bfd_boolean elf64_x86_64_create_dynamic_sections
171 PARAMS((bfd *, struct bfd_link_info *));
172 static void elf64_x86_64_copy_indirect_symbol
173 PARAMS ((struct elf_backend_data *, struct elf_link_hash_entry *,
174 struct elf_link_hash_entry *));
175 static bfd_boolean elf64_x86_64_check_relocs
176 PARAMS ((bfd *, struct bfd_link_info *, asection *sec,
177 const Elf_Internal_Rela *));
178 static asection *elf64_x86_64_gc_mark_hook
179 PARAMS ((asection *, struct bfd_link_info *, Elf_Internal_Rela *,
180 struct elf_link_hash_entry *, Elf_Internal_Sym *));
181
182 static bfd_boolean elf64_x86_64_gc_sweep_hook
183 PARAMS ((bfd *, struct bfd_link_info *, asection *,
184 const Elf_Internal_Rela *));
185
186 static struct bfd_hash_entry *link_hash_newfunc
187 PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
188 static bfd_boolean elf64_x86_64_adjust_dynamic_symbol
189 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
190
191 static bfd_boolean allocate_dynrelocs
192 PARAMS ((struct elf_link_hash_entry *, PTR));
193 static bfd_boolean readonly_dynrelocs
194 PARAMS ((struct elf_link_hash_entry *, PTR));
195 static bfd_boolean elf64_x86_64_size_dynamic_sections
196 PARAMS ((bfd *, struct bfd_link_info *));
197 static bfd_vma dtpoff_base
198 PARAMS ((struct bfd_link_info *));
199 static bfd_vma tpoff
200 PARAMS ((struct bfd_link_info *, bfd_vma));
201 static bfd_boolean elf64_x86_64_relocate_section
202 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
203 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
204 static bfd_boolean elf64_x86_64_finish_dynamic_symbol
205 PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
206 Elf_Internal_Sym *sym));
207 static bfd_boolean elf64_x86_64_finish_dynamic_sections
208 PARAMS ((bfd *, struct bfd_link_info *));
209 static enum elf_reloc_type_class elf64_x86_64_reloc_type_class
210 PARAMS ((const Elf_Internal_Rela *));
211
212 /* Given a BFD reloc type, return a HOWTO structure. */
213 static reloc_howto_type *
214 elf64_x86_64_reloc_type_lookup (abfd, code)
215 bfd *abfd ATTRIBUTE_UNUSED;
216 bfd_reloc_code_real_type code;
217 {
218 unsigned int i;
219 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
220 i++)
221 {
222 if (x86_64_reloc_map[i].bfd_reloc_val == code)
223 return &x86_64_elf_howto_table[i];
224 }
225 return 0;
226 }
227
228 /* Given an x86_64 ELF reloc type, fill in an arelent structure. */
229
230 static void
231 elf64_x86_64_info_to_howto (abfd, cache_ptr, dst)
232 bfd *abfd ATTRIBUTE_UNUSED;
233 arelent *cache_ptr;
234 Elf_Internal_Rela *dst;
235 {
236 unsigned r_type, i;
237
238 r_type = ELF64_R_TYPE (dst->r_info);
239 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT)
240 {
241 BFD_ASSERT (r_type <= (unsigned int) R_X86_64_TPOFF32);
242 i = r_type;
243 }
244 else
245 {
246 BFD_ASSERT (r_type < (unsigned int) R_X86_64_max);
247 i = r_type - ((unsigned int) R_X86_64_GNU_VTINHERIT - R_X86_64_TPOFF32 - 1);
248 }
249 cache_ptr->howto = &x86_64_elf_howto_table[i];
250 BFD_ASSERT (r_type == cache_ptr->howto->type);
251 }
252 \f
253 /* Support for core dump NOTE sections. */
254 static bfd_boolean
255 elf64_x86_64_grok_prstatus (abfd, note)
256 bfd *abfd;
257 Elf_Internal_Note *note;
258 {
259 int offset;
260 size_t raw_size;
261
262 switch (note->descsz)
263 {
264 default:
265 return FALSE;
266
267 case 336: /* sizeof(istruct elf_prstatus) on Linux/x86_64 */
268 /* pr_cursig */
269 elf_tdata (abfd)->core_signal
270 = bfd_get_16 (abfd, note->descdata + 12);
271
272 /* pr_pid */
273 elf_tdata (abfd)->core_pid
274 = bfd_get_32 (abfd, note->descdata + 32);
275
276 /* pr_reg */
277 offset = 112;
278 raw_size = 216;
279
280 break;
281 }
282
283 /* Make a ".reg/999" section. */
284 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
285 raw_size, note->descpos + offset);
286 }
287
288 static bfd_boolean
289 elf64_x86_64_grok_psinfo (abfd, note)
290 bfd *abfd;
291 Elf_Internal_Note *note;
292 {
293 switch (note->descsz)
294 {
295 default:
296 return FALSE;
297
298 case 136: /* sizeof(struct elf_prpsinfo) on Linux/x86_64 */
299 elf_tdata (abfd)->core_program
300 = _bfd_elfcore_strndup (abfd, note->descdata + 40, 16);
301 elf_tdata (abfd)->core_command
302 = _bfd_elfcore_strndup (abfd, note->descdata + 56, 80);
303 }
304
305 /* Note that for some reason, a spurious space is tacked
306 onto the end of the args in some (at least one anyway)
307 implementations, so strip it off if it exists. */
308
309 {
310 char *command = elf_tdata (abfd)->core_command;
311 int n = strlen (command);
312
313 if (0 < n && command[n - 1] == ' ')
314 command[n - 1] = '\0';
315 }
316
317 return TRUE;
318 }
319 \f
320 /* Functions for the x86-64 ELF linker. */
321
322 /* The name of the dynamic interpreter. This is put in the .interp
323 section. */
324
325 #define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
326
327 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
328 copying dynamic variables from a shared lib into an app's dynbss
329 section, and instead use a dynamic relocation to point into the
330 shared lib. */
331 #define ELIMINATE_COPY_RELOCS 1
332
333 /* The size in bytes of an entry in the global offset table. */
334
335 #define GOT_ENTRY_SIZE 8
336
337 /* The size in bytes of an entry in the procedure linkage table. */
338
339 #define PLT_ENTRY_SIZE 16
340
341 /* The first entry in a procedure linkage table looks like this. See the
342 SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
343
344 static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
345 {
346 0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
347 0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
348 0x90, 0x90, 0x90, 0x90 /* pad out to 16 bytes with nops. */
349 };
350
351 /* Subsequent entries in a procedure linkage table look like this. */
352
353 static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
354 {
355 0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
356 0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
357 0x68, /* pushq immediate */
358 0, 0, 0, 0, /* replaced with index into relocation table. */
359 0xe9, /* jmp relative */
360 0, 0, 0, 0 /* replaced with offset to start of .plt0. */
361 };
362
363 /* The x86-64 linker needs to keep track of the number of relocs that
364 it decides to copy as dynamic relocs in check_relocs for each symbol.
365 This is so that it can later discard them if they are found to be
366 unnecessary. We store the information in a field extending the
367 regular ELF linker hash table. */
368
369 struct elf64_x86_64_dyn_relocs
370 {
371 /* Next section. */
372 struct elf64_x86_64_dyn_relocs *next;
373
374 /* The input section of the reloc. */
375 asection *sec;
376
377 /* Total number of relocs copied for the input section. */
378 bfd_size_type count;
379
380 /* Number of pc-relative relocs copied for the input section. */
381 bfd_size_type pc_count;
382 };
383
384 /* x86-64 ELF linker hash entry. */
385
386 struct elf64_x86_64_link_hash_entry
387 {
388 struct elf_link_hash_entry elf;
389
390 /* Track dynamic relocs copied for this symbol. */
391 struct elf64_x86_64_dyn_relocs *dyn_relocs;
392
393 #define GOT_UNKNOWN 0
394 #define GOT_NORMAL 1
395 #define GOT_TLS_GD 2
396 #define GOT_TLS_IE 3
397 unsigned char tls_type;
398 };
399
400 #define elf64_x86_64_hash_entry(ent) \
401 ((struct elf64_x86_64_link_hash_entry *)(ent))
402
403 struct elf64_x86_64_obj_tdata
404 {
405 struct elf_obj_tdata root;
406
407 /* tls_type for each local got entry. */
408 char *local_got_tls_type;
409 };
410
411 #define elf64_x86_64_tdata(abfd) \
412 ((struct elf64_x86_64_obj_tdata *) (abfd)->tdata.any)
413
414 #define elf64_x86_64_local_got_tls_type(abfd) \
415 (elf64_x86_64_tdata (abfd)->local_got_tls_type)
416
417
418 /* x86-64 ELF linker hash table. */
419
420 struct elf64_x86_64_link_hash_table
421 {
422 struct elf_link_hash_table elf;
423
424 /* Short-cuts to get to dynamic linker sections. */
425 asection *sgot;
426 asection *sgotplt;
427 asection *srelgot;
428 asection *splt;
429 asection *srelplt;
430 asection *sdynbss;
431 asection *srelbss;
432
433 union {
434 bfd_signed_vma refcount;
435 bfd_vma offset;
436 } tls_ld_got;
437
438 /* Small local sym to section mapping cache. */
439 struct sym_sec_cache sym_sec;
440 };
441
442 /* Get the x86-64 ELF linker hash table from a link_info structure. */
443
444 #define elf64_x86_64_hash_table(p) \
445 ((struct elf64_x86_64_link_hash_table *) ((p)->hash))
446
447 /* Create an entry in an x86-64 ELF linker hash table. */
448
449 static struct bfd_hash_entry *
450 link_hash_newfunc (entry, table, string)
451 struct bfd_hash_entry *entry;
452 struct bfd_hash_table *table;
453 const char *string;
454 {
455 /* Allocate the structure if it has not already been allocated by a
456 subclass. */
457 if (entry == NULL)
458 {
459 entry = bfd_hash_allocate (table,
460 sizeof (struct elf64_x86_64_link_hash_entry));
461 if (entry == NULL)
462 return entry;
463 }
464
465 /* Call the allocation method of the superclass. */
466 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
467 if (entry != NULL)
468 {
469 struct elf64_x86_64_link_hash_entry *eh;
470
471 eh = (struct elf64_x86_64_link_hash_entry *) entry;
472 eh->dyn_relocs = NULL;
473 eh->tls_type = GOT_UNKNOWN;
474 }
475
476 return entry;
477 }
478
479 /* Create an X86-64 ELF linker hash table. */
480
481 static struct bfd_link_hash_table *
482 elf64_x86_64_link_hash_table_create (abfd)
483 bfd *abfd;
484 {
485 struct elf64_x86_64_link_hash_table *ret;
486 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table);
487
488 ret = (struct elf64_x86_64_link_hash_table *) bfd_malloc (amt);
489 if (ret == NULL)
490 return NULL;
491
492 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc))
493 {
494 free (ret);
495 return NULL;
496 }
497
498 ret->sgot = NULL;
499 ret->sgotplt = NULL;
500 ret->srelgot = NULL;
501 ret->splt = NULL;
502 ret->srelplt = NULL;
503 ret->sdynbss = NULL;
504 ret->srelbss = NULL;
505 ret->sym_sec.abfd = NULL;
506 ret->tls_ld_got.refcount = 0;
507
508 return &ret->elf.root;
509 }
510
511 /* Create .got, .gotplt, and .rela.got sections in DYNOBJ, and set up
512 shortcuts to them in our hash table. */
513
514 static bfd_boolean
515 create_got_section (dynobj, info)
516 bfd *dynobj;
517 struct bfd_link_info *info;
518 {
519 struct elf64_x86_64_link_hash_table *htab;
520
521 if (! _bfd_elf_create_got_section (dynobj, info))
522 return FALSE;
523
524 htab = elf64_x86_64_hash_table (info);
525 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
526 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
527 if (!htab->sgot || !htab->sgotplt)
528 abort ();
529
530 htab->srelgot = bfd_make_section (dynobj, ".rela.got");
531 if (htab->srelgot == NULL
532 || ! bfd_set_section_flags (dynobj, htab->srelgot,
533 (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
534 | SEC_IN_MEMORY | SEC_LINKER_CREATED
535 | SEC_READONLY))
536 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 3))
537 return FALSE;
538 return TRUE;
539 }
540
541 /* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and
542 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our
543 hash table. */
544
545 static bfd_boolean
546 elf64_x86_64_create_dynamic_sections (dynobj, info)
547 bfd *dynobj;
548 struct bfd_link_info *info;
549 {
550 struct elf64_x86_64_link_hash_table *htab;
551
552 htab = elf64_x86_64_hash_table (info);
553 if (!htab->sgot && !create_got_section (dynobj, info))
554 return FALSE;
555
556 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
557 return FALSE;
558
559 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
560 htab->srelplt = bfd_get_section_by_name (dynobj, ".rela.plt");
561 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
562 if (!info->shared)
563 htab->srelbss = bfd_get_section_by_name (dynobj, ".rela.bss");
564
565 if (!htab->splt || !htab->srelplt || !htab->sdynbss
566 || (!info->shared && !htab->srelbss))
567 abort ();
568
569 return TRUE;
570 }
571
572 /* Copy the extra info we tack onto an elf_link_hash_entry. */
573
574 static void
575 elf64_x86_64_copy_indirect_symbol (bed, dir, ind)
576 struct elf_backend_data *bed;
577 struct elf_link_hash_entry *dir, *ind;
578 {
579 struct elf64_x86_64_link_hash_entry *edir, *eind;
580
581 edir = (struct elf64_x86_64_link_hash_entry *) dir;
582 eind = (struct elf64_x86_64_link_hash_entry *) ind;
583
584 if (eind->dyn_relocs != NULL)
585 {
586 if (edir->dyn_relocs != NULL)
587 {
588 struct elf64_x86_64_dyn_relocs **pp;
589 struct elf64_x86_64_dyn_relocs *p;
590
591 if (ind->root.type == bfd_link_hash_indirect)
592 abort ();
593
594 /* Add reloc counts against the weak sym to the strong sym
595 list. Merge any entries against the same section. */
596 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
597 {
598 struct elf64_x86_64_dyn_relocs *q;
599
600 for (q = edir->dyn_relocs; q != NULL; q = q->next)
601 if (q->sec == p->sec)
602 {
603 q->pc_count += p->pc_count;
604 q->count += p->count;
605 *pp = p->next;
606 break;
607 }
608 if (q == NULL)
609 pp = &p->next;
610 }
611 *pp = edir->dyn_relocs;
612 }
613
614 edir->dyn_relocs = eind->dyn_relocs;
615 eind->dyn_relocs = NULL;
616 }
617
618 if (ind->root.type == bfd_link_hash_indirect
619 && dir->got.refcount <= 0)
620 {
621 edir->tls_type = eind->tls_type;
622 eind->tls_type = GOT_UNKNOWN;
623 }
624
625 if (ELIMINATE_COPY_RELOCS
626 && ind->root.type != bfd_link_hash_indirect
627 && (dir->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
628 /* If called to transfer flags for a weakdef during processing
629 of elf_adjust_dynamic_symbol, don't copy ELF_LINK_NON_GOT_REF.
630 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
631 dir->elf_link_hash_flags |=
632 (ind->elf_link_hash_flags & (ELF_LINK_HASH_REF_DYNAMIC
633 | ELF_LINK_HASH_REF_REGULAR
634 | ELF_LINK_HASH_REF_REGULAR_NONWEAK));
635 else
636 _bfd_elf_link_hash_copy_indirect (bed, dir, ind);
637 }
638
639 static bfd_boolean
640 elf64_x86_64_mkobject (abfd)
641 bfd *abfd;
642 {
643 bfd_size_type amt = sizeof (struct elf64_x86_64_obj_tdata);
644 abfd->tdata.any = bfd_zalloc (abfd, amt);
645 if (abfd->tdata.any == NULL)
646 return FALSE;
647 return TRUE;
648 }
649
650 static bfd_boolean
651 elf64_x86_64_elf_object_p (abfd)
652 bfd *abfd;
653 {
654 /* Allocate our special target data. */
655 struct elf64_x86_64_obj_tdata *new_tdata;
656 bfd_size_type amt = sizeof (struct elf64_x86_64_obj_tdata);
657 new_tdata = bfd_zalloc (abfd, amt);
658 if (new_tdata == NULL)
659 return FALSE;
660 new_tdata->root = *abfd->tdata.elf_obj_data;
661 abfd->tdata.any = new_tdata;
662 /* Set the right machine number for an x86-64 elf64 file. */
663 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
664 return TRUE;
665 }
666
667 static int
668 elf64_x86_64_tls_transition (info, r_type, is_local)
669 struct bfd_link_info *info;
670 int r_type;
671 int is_local;
672 {
673 if (info->shared)
674 return r_type;
675
676 switch (r_type)
677 {
678 case R_X86_64_TLSGD:
679 case R_X86_64_GOTTPOFF:
680 if (is_local)
681 return R_X86_64_TPOFF32;
682 return R_X86_64_GOTTPOFF;
683 case R_X86_64_TLSLD:
684 return R_X86_64_TPOFF32;
685 }
686
687 return r_type;
688 }
689
690 /* Look through the relocs for a section during the first phase, and
691 calculate needed space in the global offset table, procedure
692 linkage table, and dynamic reloc sections. */
693
694 static bfd_boolean
695 elf64_x86_64_check_relocs (abfd, info, sec, relocs)
696 bfd *abfd;
697 struct bfd_link_info *info;
698 asection *sec;
699 const Elf_Internal_Rela *relocs;
700 {
701 struct elf64_x86_64_link_hash_table *htab;
702 Elf_Internal_Shdr *symtab_hdr;
703 struct elf_link_hash_entry **sym_hashes;
704 const Elf_Internal_Rela *rel;
705 const Elf_Internal_Rela *rel_end;
706 asection *sreloc;
707
708 if (info->relocateable)
709 return TRUE;
710
711 htab = elf64_x86_64_hash_table (info);
712 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
713 sym_hashes = elf_sym_hashes (abfd);
714
715 sreloc = NULL;
716
717 rel_end = relocs + sec->reloc_count;
718 for (rel = relocs; rel < rel_end; rel++)
719 {
720 unsigned int r_type;
721 unsigned long r_symndx;
722 struct elf_link_hash_entry *h;
723
724 r_symndx = ELF64_R_SYM (rel->r_info);
725 r_type = ELF64_R_TYPE (rel->r_info);
726
727 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
728 {
729 (*_bfd_error_handler) (_("%s: bad symbol index: %d"),
730 bfd_archive_filename (abfd),
731 r_symndx);
732 return FALSE;
733 }
734
735 if (r_symndx < symtab_hdr->sh_info)
736 h = NULL;
737 else
738 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
739
740 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
741 switch (r_type)
742 {
743 case R_X86_64_TLSLD:
744 htab->tls_ld_got.refcount += 1;
745 goto create_got;
746
747 case R_X86_64_TPOFF32:
748 if (info->shared)
749 {
750 (*_bfd_error_handler)
751 (_("%s: relocation %s can not be used when making a shared object; recompile with -fPIC"),
752 bfd_archive_filename (abfd),
753 x86_64_elf_howto_table[r_type].name);
754 bfd_set_error (bfd_error_bad_value);
755 return FALSE;
756 }
757 break;
758
759 case R_X86_64_GOTTPOFF:
760 if (info->shared)
761 info->flags |= DF_STATIC_TLS;
762 /* Fall through */
763
764 case R_X86_64_GOT32:
765 case R_X86_64_GOTPCREL:
766 case R_X86_64_TLSGD:
767 /* This symbol requires a global offset table entry. */
768 {
769 int tls_type, old_tls_type;
770
771 switch (r_type)
772 {
773 default: tls_type = GOT_NORMAL; break;
774 case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
775 case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
776 }
777
778 if (h != NULL)
779 {
780 h->got.refcount += 1;
781 old_tls_type = elf64_x86_64_hash_entry (h)->tls_type;
782 }
783 else
784 {
785 bfd_signed_vma *local_got_refcounts;
786
787 /* This is a global offset table entry for a local symbol. */
788 local_got_refcounts = elf_local_got_refcounts (abfd);
789 if (local_got_refcounts == NULL)
790 {
791 bfd_size_type size;
792
793 size = symtab_hdr->sh_info;
794 size *= sizeof (bfd_signed_vma) + sizeof (char);
795 local_got_refcounts = ((bfd_signed_vma *)
796 bfd_zalloc (abfd, size));
797 if (local_got_refcounts == NULL)
798 return FALSE;
799 elf_local_got_refcounts (abfd) = local_got_refcounts;
800 elf64_x86_64_local_got_tls_type (abfd)
801 = (char *) (local_got_refcounts + symtab_hdr->sh_info);
802 }
803 local_got_refcounts[r_symndx] += 1;
804 old_tls_type
805 = elf64_x86_64_local_got_tls_type (abfd) [r_symndx];
806 }
807
808 /* If a TLS symbol is accessed using IE at least once,
809 there is no point to use dynamic model for it. */
810 if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
811 && (old_tls_type != GOT_TLS_GD || tls_type != GOT_TLS_IE))
812 {
813 if (old_tls_type == GOT_TLS_IE && tls_type == GOT_TLS_GD)
814 tls_type = old_tls_type;
815 else
816 {
817 (*_bfd_error_handler)
818 (_("%s: %s' accessed both as normal and thread local symbol"),
819 bfd_archive_filename (abfd),
820 h ? h->root.root.string : "<local>");
821 return FALSE;
822 }
823 }
824
825 if (old_tls_type != tls_type)
826 {
827 if (h != NULL)
828 elf64_x86_64_hash_entry (h)->tls_type = tls_type;
829 else
830 elf64_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
831 }
832 }
833 /* Fall through */
834
835 //case R_X86_64_GOTPCREL:
836 create_got:
837 if (htab->sgot == NULL)
838 {
839 if (htab->elf.dynobj == NULL)
840 htab->elf.dynobj = abfd;
841 if (!create_got_section (htab->elf.dynobj, info))
842 return FALSE;
843 }
844 break;
845
846 case R_X86_64_PLT32:
847 /* This symbol requires a procedure linkage table entry. We
848 actually build the entry in adjust_dynamic_symbol,
849 because this might be a case of linking PIC code which is
850 never referenced by a dynamic object, in which case we
851 don't need to generate a procedure linkage table entry
852 after all. */
853
854 /* If this is a local symbol, we resolve it directly without
855 creating a procedure linkage table entry. */
856 if (h == NULL)
857 continue;
858
859 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
860 h->plt.refcount += 1;
861 break;
862
863 case R_X86_64_8:
864 case R_X86_64_16:
865 case R_X86_64_32:
866 case R_X86_64_32S:
867 /* Let's help debug shared library creation. These relocs
868 cannot be used in shared libs. Don't error out for
869 sections we don't care about, such as debug sections or
870 non-constant sections. */
871 if (info->shared
872 && (sec->flags & SEC_ALLOC) != 0
873 && (sec->flags & SEC_READONLY) != 0)
874 {
875 (*_bfd_error_handler)
876 (_("%s: relocation %s can not be used when making a shared object; recompile with -fPIC"),
877 bfd_archive_filename (abfd),
878 x86_64_elf_howto_table[r_type].name);
879 bfd_set_error (bfd_error_bad_value);
880 return FALSE;
881 }
882 /* Fall through. */
883
884 case R_X86_64_PC8:
885 case R_X86_64_PC16:
886 case R_X86_64_PC32:
887 case R_X86_64_64:
888 if (h != NULL && !info->shared)
889 {
890 /* If this reloc is in a read-only section, we might
891 need a copy reloc. We can't check reliably at this
892 stage whether the section is read-only, as input
893 sections have not yet been mapped to output sections.
894 Tentatively set the flag for now, and correct in
895 adjust_dynamic_symbol. */
896 h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF;
897
898 /* We may need a .plt entry if the function this reloc
899 refers to is in a shared lib. */
900 h->plt.refcount += 1;
901 }
902
903 /* If we are creating a shared library, and this is a reloc
904 against a global symbol, or a non PC relative reloc
905 against a local symbol, then we need to copy the reloc
906 into the shared library. However, if we are linking with
907 -Bsymbolic, we do not need to copy a reloc against a
908 global symbol which is defined in an object we are
909 including in the link (i.e., DEF_REGULAR is set). At
910 this point we have not seen all the input files, so it is
911 possible that DEF_REGULAR is not set now but will be set
912 later (it is never cleared). In case of a weak definition,
913 DEF_REGULAR may be cleared later by a strong definition in
914 a shared library. We account for that possibility below by
915 storing information in the relocs_copied field of the hash
916 table entry. A similar situation occurs when creating
917 shared libraries and symbol visibility changes render the
918 symbol local.
919
920 If on the other hand, we are creating an executable, we
921 may need to keep relocations for symbols satisfied by a
922 dynamic library if we manage to avoid copy relocs for the
923 symbol. */
924 if ((info->shared
925 && (sec->flags & SEC_ALLOC) != 0
926 && (((r_type != R_X86_64_PC8)
927 && (r_type != R_X86_64_PC16)
928 && (r_type != R_X86_64_PC32))
929 || (h != NULL
930 && (! info->symbolic
931 || h->root.type == bfd_link_hash_defweak
932 || (h->elf_link_hash_flags
933 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
934 || (ELIMINATE_COPY_RELOCS
935 && !info->shared
936 && (sec->flags & SEC_ALLOC) != 0
937 && h != NULL
938 && (h->root.type == bfd_link_hash_defweak
939 || (h->elf_link_hash_flags
940 & ELF_LINK_HASH_DEF_REGULAR) == 0)))
941 {
942 struct elf64_x86_64_dyn_relocs *p;
943 struct elf64_x86_64_dyn_relocs **head;
944
945 /* We must copy these reloc types into the output file.
946 Create a reloc section in dynobj and make room for
947 this reloc. */
948 if (sreloc == NULL)
949 {
950 const char *name;
951 bfd *dynobj;
952
953 name = (bfd_elf_string_from_elf_section
954 (abfd,
955 elf_elfheader (abfd)->e_shstrndx,
956 elf_section_data (sec)->rel_hdr.sh_name));
957 if (name == NULL)
958 return FALSE;
959
960 if (strncmp (name, ".rela", 5) != 0
961 || strcmp (bfd_get_section_name (abfd, sec),
962 name + 5) != 0)
963 {
964 (*_bfd_error_handler)
965 (_("%s: bad relocation section name `%s\'"),
966 bfd_archive_filename (abfd), name);
967 }
968
969 if (htab->elf.dynobj == NULL)
970 htab->elf.dynobj = abfd;
971
972 dynobj = htab->elf.dynobj;
973
974 sreloc = bfd_get_section_by_name (dynobj, name);
975 if (sreloc == NULL)
976 {
977 flagword flags;
978
979 sreloc = bfd_make_section (dynobj, name);
980 flags = (SEC_HAS_CONTENTS | SEC_READONLY
981 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
982 if ((sec->flags & SEC_ALLOC) != 0)
983 flags |= SEC_ALLOC | SEC_LOAD;
984 if (sreloc == NULL
985 || ! bfd_set_section_flags (dynobj, sreloc, flags)
986 || ! bfd_set_section_alignment (dynobj, sreloc, 3))
987 return FALSE;
988 }
989 elf_section_data (sec)->sreloc = sreloc;
990 }
991
992 /* If this is a global symbol, we count the number of
993 relocations we need for this symbol. */
994 if (h != NULL)
995 {
996 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs;
997 }
998 else
999 {
1000 /* Track dynamic relocs needed for local syms too.
1001 We really need local syms available to do this
1002 easily. Oh well. */
1003
1004 asection *s;
1005 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
1006 sec, r_symndx);
1007 if (s == NULL)
1008 return FALSE;
1009
1010 head = ((struct elf64_x86_64_dyn_relocs **)
1011 &elf_section_data (s)->local_dynrel);
1012 }
1013
1014 p = *head;
1015 if (p == NULL || p->sec != sec)
1016 {
1017 bfd_size_type amt = sizeof *p;
1018 p = ((struct elf64_x86_64_dyn_relocs *)
1019 bfd_alloc (htab->elf.dynobj, amt));
1020 if (p == NULL)
1021 return FALSE;
1022 p->next = *head;
1023 *head = p;
1024 p->sec = sec;
1025 p->count = 0;
1026 p->pc_count = 0;
1027 }
1028
1029 p->count += 1;
1030 if (r_type == R_X86_64_PC8
1031 || r_type == R_X86_64_PC16
1032 || r_type == R_X86_64_PC32)
1033 p->pc_count += 1;
1034 }
1035 break;
1036
1037 /* This relocation describes the C++ object vtable hierarchy.
1038 Reconstruct it for later use during GC. */
1039 case R_X86_64_GNU_VTINHERIT:
1040 if (!_bfd_elf64_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
1041 return FALSE;
1042 break;
1043
1044 /* This relocation describes which C++ vtable entries are actually
1045 used. Record for later use during GC. */
1046 case R_X86_64_GNU_VTENTRY:
1047 if (!_bfd_elf64_gc_record_vtentry (abfd, sec, h, rel->r_addend))
1048 return FALSE;
1049 break;
1050
1051 default:
1052 break;
1053 }
1054 }
1055
1056 return TRUE;
1057 }
1058
1059 /* Return the section that should be marked against GC for a given
1060 relocation. */
1061
1062 static asection *
1063 elf64_x86_64_gc_mark_hook (sec, info, rel, h, sym)
1064 asection *sec;
1065 struct bfd_link_info *info ATTRIBUTE_UNUSED;
1066 Elf_Internal_Rela *rel;
1067 struct elf_link_hash_entry *h;
1068 Elf_Internal_Sym *sym;
1069 {
1070 if (h != NULL)
1071 {
1072 switch (ELF64_R_TYPE (rel->r_info))
1073 {
1074 case R_X86_64_GNU_VTINHERIT:
1075 case R_X86_64_GNU_VTENTRY:
1076 break;
1077
1078 default:
1079 switch (h->root.type)
1080 {
1081 case bfd_link_hash_defined:
1082 case bfd_link_hash_defweak:
1083 return h->root.u.def.section;
1084
1085 case bfd_link_hash_common:
1086 return h->root.u.c.p->section;
1087
1088 default:
1089 break;
1090 }
1091 }
1092 }
1093 else
1094 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
1095
1096 return NULL;
1097 }
1098
1099 /* Update the got entry reference counts for the section being removed. */
1100
1101 static bfd_boolean
1102 elf64_x86_64_gc_sweep_hook (abfd, info, sec, relocs)
1103 bfd *abfd;
1104 struct bfd_link_info *info;
1105 asection *sec;
1106 const Elf_Internal_Rela *relocs;
1107 {
1108 Elf_Internal_Shdr *symtab_hdr;
1109 struct elf_link_hash_entry **sym_hashes;
1110 bfd_signed_vma *local_got_refcounts;
1111 const Elf_Internal_Rela *rel, *relend;
1112
1113 elf_section_data (sec)->local_dynrel = NULL;
1114
1115 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1116 sym_hashes = elf_sym_hashes (abfd);
1117 local_got_refcounts = elf_local_got_refcounts (abfd);
1118
1119 relend = relocs + sec->reloc_count;
1120 for (rel = relocs; rel < relend; rel++)
1121 {
1122 unsigned long r_symndx;
1123 unsigned int r_type;
1124 struct elf_link_hash_entry *h = NULL;
1125
1126 r_symndx = ELF64_R_SYM (rel->r_info);
1127 if (r_symndx >= symtab_hdr->sh_info)
1128 {
1129 struct elf64_x86_64_link_hash_entry *eh;
1130 struct elf64_x86_64_dyn_relocs **pp;
1131 struct elf64_x86_64_dyn_relocs *p;
1132
1133 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1134 eh = (struct elf64_x86_64_link_hash_entry *) h;
1135
1136 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1137 if (p->sec == sec)
1138 {
1139 /* Everything must go for SEC. */
1140 *pp = p->next;
1141 break;
1142 }
1143 }
1144
1145 r_type = ELF64_R_TYPE (rel->r_info);
1146 r_type = elf64_x86_64_tls_transition (info, r_type, h != NULL);
1147 switch (r_type)
1148 {
1149 case R_X86_64_TLSLD:
1150 if (elf64_x86_64_hash_table (info)->tls_ld_got.refcount > 0)
1151 elf64_x86_64_hash_table (info)->tls_ld_got.refcount -= 1;
1152 break;
1153
1154 case R_X86_64_TLSGD:
1155 case R_X86_64_GOTTPOFF:
1156 case R_X86_64_GOT32:
1157 case R_X86_64_GOTPCREL:
1158 if (h != NULL)
1159 {
1160 if (h->got.refcount > 0)
1161 h->got.refcount -= 1;
1162 }
1163 else if (local_got_refcounts != NULL)
1164 {
1165 if (local_got_refcounts[r_symndx] > 0)
1166 local_got_refcounts[r_symndx] -= 1;
1167 }
1168 break;
1169
1170 case R_X86_64_8:
1171 case R_X86_64_16:
1172 case R_X86_64_32:
1173 case R_X86_64_64:
1174 case R_X86_64_32S:
1175 case R_X86_64_PC8:
1176 case R_X86_64_PC16:
1177 case R_X86_64_PC32:
1178 if (info->shared)
1179 break;
1180 /* Fall thru */
1181
1182 case R_X86_64_PLT32:
1183 if (h != NULL)
1184 {
1185 if (h->plt.refcount > 0)
1186 h->plt.refcount -= 1;
1187 }
1188 break;
1189
1190 default:
1191 break;
1192 }
1193 }
1194
1195 return TRUE;
1196 }
1197
1198 /* Adjust a symbol defined by a dynamic object and referenced by a
1199 regular object. The current definition is in some section of the
1200 dynamic object, but we're not including those sections. We have to
1201 change the definition to something the rest of the link can
1202 understand. */
1203
1204 static bfd_boolean
1205 elf64_x86_64_adjust_dynamic_symbol (info, h)
1206 struct bfd_link_info *info;
1207 struct elf_link_hash_entry *h;
1208 {
1209 struct elf64_x86_64_link_hash_table *htab;
1210 asection *s;
1211 unsigned int power_of_two;
1212
1213 /* If this is a function, put it in the procedure linkage table. We
1214 will fill in the contents of the procedure linkage table later,
1215 when we know the address of the .got section. */
1216 if (h->type == STT_FUNC
1217 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
1218 {
1219 if (h->plt.refcount <= 0
1220 || (! info->shared
1221 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
1222 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0
1223 && h->root.type != bfd_link_hash_undefweak
1224 && h->root.type != bfd_link_hash_undefined))
1225 {
1226 /* This case can occur if we saw a PLT32 reloc in an input
1227 file, but the symbol was never referred to by a dynamic
1228 object, or if all references were garbage collected. In
1229 such a case, we don't actually need to build a procedure
1230 linkage table, and we can just do a PC32 reloc instead. */
1231 h->plt.offset = (bfd_vma) -1;
1232 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1233 }
1234
1235 return TRUE;
1236 }
1237 else
1238 /* It's possible that we incorrectly decided a .plt reloc was
1239 needed for an R_X86_64_PC32 reloc to a non-function sym in
1240 check_relocs. We can't decide accurately between function and
1241 non-function syms in check-relocs; Objects loaded later in
1242 the link may change h->type. So fix it now. */
1243 h->plt.offset = (bfd_vma) -1;
1244
1245 /* If this is a weak symbol, and there is a real definition, the
1246 processor independent code will have arranged for us to see the
1247 real definition first, and we can just use the same value. */
1248 if (h->weakdef != NULL)
1249 {
1250 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
1251 || h->weakdef->root.type == bfd_link_hash_defweak);
1252 h->root.u.def.section = h->weakdef->root.u.def.section;
1253 h->root.u.def.value = h->weakdef->root.u.def.value;
1254 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1255 h->elf_link_hash_flags
1256 = ((h->elf_link_hash_flags & ~ELF_LINK_NON_GOT_REF)
1257 | (h->weakdef->elf_link_hash_flags & ELF_LINK_NON_GOT_REF));
1258 return TRUE;
1259 }
1260
1261 /* This is a reference to a symbol defined by a dynamic object which
1262 is not a function. */
1263
1264 /* If we are creating a shared library, we must presume that the
1265 only references to the symbol are via the global offset table.
1266 For such cases we need not do anything here; the relocations will
1267 be handled correctly by relocate_section. */
1268 if (info->shared)
1269 return TRUE;
1270
1271 /* If there are no references to this symbol that do not use the
1272 GOT, we don't need to generate a copy reloc. */
1273 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0)
1274 return TRUE;
1275
1276 /* If -z nocopyreloc was given, we won't generate them either. */
1277 if (info->nocopyreloc)
1278 {
1279 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1280 return TRUE;
1281 }
1282
1283 if (ELIMINATE_COPY_RELOCS)
1284 {
1285 struct elf64_x86_64_link_hash_entry * eh;
1286 struct elf64_x86_64_dyn_relocs *p;
1287
1288 eh = (struct elf64_x86_64_link_hash_entry *) h;
1289 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1290 {
1291 s = p->sec->output_section;
1292 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1293 break;
1294 }
1295
1296 /* If we didn't find any dynamic relocs in read-only sections, then
1297 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1298 if (p == NULL)
1299 {
1300 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1301 return TRUE;
1302 }
1303 }
1304
1305 /* We must allocate the symbol in our .dynbss section, which will
1306 become part of the .bss section of the executable. There will be
1307 an entry for this symbol in the .dynsym section. The dynamic
1308 object will contain position independent code, so all references
1309 from the dynamic object to this symbol will go through the global
1310 offset table. The dynamic linker will use the .dynsym entry to
1311 determine the address it must put in the global offset table, so
1312 both the dynamic object and the regular object will refer to the
1313 same memory location for the variable. */
1314
1315 htab = elf64_x86_64_hash_table (info);
1316
1317 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
1318 to copy the initial value out of the dynamic object and into the
1319 runtime process image. */
1320 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1321 {
1322 htab->srelbss->_raw_size += sizeof (Elf64_External_Rela);
1323 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
1324 }
1325
1326 /* We need to figure out the alignment required for this symbol. I
1327 have no idea how ELF linkers handle this. 16-bytes is the size
1328 of the largest type that requires hard alignment -- long double. */
1329 /* FIXME: This is VERY ugly. Should be fixed for all architectures using
1330 this construct. */
1331 power_of_two = bfd_log2 (h->size);
1332 if (power_of_two > 4)
1333 power_of_two = 4;
1334
1335 /* Apply the required alignment. */
1336 s = htab->sdynbss;
1337 s->_raw_size = BFD_ALIGN (s->_raw_size, (bfd_size_type) (1 << power_of_two));
1338 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1339 {
1340 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1341 return FALSE;
1342 }
1343
1344 /* Define the symbol as being at this point in the section. */
1345 h->root.u.def.section = s;
1346 h->root.u.def.value = s->_raw_size;
1347
1348 /* Increment the section size to make room for the symbol. */
1349 s->_raw_size += h->size;
1350
1351 return TRUE;
1352 }
1353
1354 /* This is the condition under which elf64_x86_64_finish_dynamic_symbol
1355 will be called from elflink.h. If elflink.h doesn't call our
1356 finish_dynamic_symbol routine, we'll need to do something about
1357 initializing any .plt and .got entries in elf64_x86_64_relocate_section. */
1358 #define WILL_CALL_FINISH_DYNAMIC_SYMBOL(DYN, INFO, H) \
1359 ((DYN) \
1360 && ((INFO)->shared \
1361 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) \
1362 && ((H)->dynindx != -1 \
1363 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0))
1364
1365 /* Allocate space in .plt, .got and associated reloc sections for
1366 dynamic relocs. */
1367
1368 static bfd_boolean
1369 allocate_dynrelocs (h, inf)
1370 struct elf_link_hash_entry *h;
1371 PTR inf;
1372 {
1373 struct bfd_link_info *info;
1374 struct elf64_x86_64_link_hash_table *htab;
1375 struct elf64_x86_64_link_hash_entry *eh;
1376 struct elf64_x86_64_dyn_relocs *p;
1377
1378 if (h->root.type == bfd_link_hash_indirect)
1379 return TRUE;
1380
1381 if (h->root.type == bfd_link_hash_warning)
1382 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1383
1384 info = (struct bfd_link_info *) inf;
1385 htab = elf64_x86_64_hash_table (info);
1386
1387 if (htab->elf.dynamic_sections_created
1388 && h->plt.refcount > 0)
1389 {
1390 /* Make sure this symbol is output as a dynamic symbol.
1391 Undefined weak syms won't yet be marked as dynamic. */
1392 if (h->dynindx == -1
1393 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1394 {
1395 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1396 return FALSE;
1397 }
1398
1399 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, info, h))
1400 {
1401 asection *s = htab->splt;
1402
1403 /* If this is the first .plt entry, make room for the special
1404 first entry. */
1405 if (s->_raw_size == 0)
1406 s->_raw_size += PLT_ENTRY_SIZE;
1407
1408 h->plt.offset = s->_raw_size;
1409
1410 /* If this symbol is not defined in a regular file, and we are
1411 not generating a shared library, then set the symbol to this
1412 location in the .plt. This is required to make function
1413 pointers compare as equal between the normal executable and
1414 the shared library. */
1415 if (! info->shared
1416 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1417 {
1418 h->root.u.def.section = s;
1419 h->root.u.def.value = h->plt.offset;
1420 }
1421
1422 /* Make room for this entry. */
1423 s->_raw_size += PLT_ENTRY_SIZE;
1424
1425 /* We also need to make an entry in the .got.plt section, which
1426 will be placed in the .got section by the linker script. */
1427 htab->sgotplt->_raw_size += GOT_ENTRY_SIZE;
1428
1429 /* We also need to make an entry in the .rela.plt section. */
1430 htab->srelplt->_raw_size += sizeof (Elf64_External_Rela);
1431 }
1432 else
1433 {
1434 h->plt.offset = (bfd_vma) -1;
1435 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1436 }
1437 }
1438 else
1439 {
1440 h->plt.offset = (bfd_vma) -1;
1441 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1442 }
1443
1444 /* If R_X86_64_GOTTPOFF symbol is now local to the binary,
1445 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
1446 if (h->got.refcount > 0
1447 && !info->shared
1448 && h->dynindx == -1
1449 && elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
1450 h->got.offset = (bfd_vma) -1;
1451 else if (h->got.refcount > 0)
1452 {
1453 asection *s;
1454 bfd_boolean dyn;
1455 int tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1456
1457 /* Make sure this symbol is output as a dynamic symbol.
1458 Undefined weak syms won't yet be marked as dynamic. */
1459 if (h->dynindx == -1
1460 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1461 {
1462 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1463 return FALSE;
1464 }
1465
1466 s = htab->sgot;
1467 h->got.offset = s->_raw_size;
1468 s->_raw_size += GOT_ENTRY_SIZE;
1469 /* R_X86_64_TLSGD needs 2 consecutive GOT slots. */
1470 if (tls_type == GOT_TLS_GD)
1471 s->_raw_size += GOT_ENTRY_SIZE;
1472 dyn = htab->elf.dynamic_sections_created;
1473 /* R_X86_64_TLSGD needs one dynamic relocation if local symbol
1474 and two if global.
1475 R_X86_64_GOTTPOFF needs one dynamic relocation. */
1476 if ((tls_type == GOT_TLS_GD && h->dynindx == -1)
1477 || tls_type == GOT_TLS_IE)
1478 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1479 else if (tls_type == GOT_TLS_GD)
1480 htab->srelgot->_raw_size += 2 * sizeof (Elf64_External_Rela);
1481 else if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h))
1482 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1483 }
1484 else
1485 h->got.offset = (bfd_vma) -1;
1486
1487 eh = (struct elf64_x86_64_link_hash_entry *) h;
1488 if (eh->dyn_relocs == NULL)
1489 return TRUE;
1490
1491 /* In the shared -Bsymbolic case, discard space allocated for
1492 dynamic pc-relative relocs against symbols which turn out to be
1493 defined in regular objects. For the normal shared case, discard
1494 space for pc-relative relocs that have become local due to symbol
1495 visibility changes. */
1496
1497 if (info->shared)
1498 {
1499 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
1500 && ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0
1501 || info->symbolic))
1502 {
1503 struct elf64_x86_64_dyn_relocs **pp;
1504
1505 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1506 {
1507 p->count -= p->pc_count;
1508 p->pc_count = 0;
1509 if (p->count == 0)
1510 *pp = p->next;
1511 else
1512 pp = &p->next;
1513 }
1514 }
1515 }
1516 else if (ELIMINATE_COPY_RELOCS)
1517 {
1518 /* For the non-shared case, discard space for relocs against
1519 symbols which turn out to need copy relocs or are not
1520 dynamic. */
1521
1522 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1523 && (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1524 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1525 || (htab->elf.dynamic_sections_created
1526 && (h->root.type == bfd_link_hash_undefweak
1527 || h->root.type == bfd_link_hash_undefined))))
1528 {
1529 /* Make sure this symbol is output as a dynamic symbol.
1530 Undefined weak syms won't yet be marked as dynamic. */
1531 if (h->dynindx == -1
1532 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1533 {
1534 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1535 return FALSE;
1536 }
1537
1538 /* If that succeeded, we know we'll be keeping all the
1539 relocs. */
1540 if (h->dynindx != -1)
1541 goto keep;
1542 }
1543
1544 eh->dyn_relocs = NULL;
1545
1546 keep: ;
1547 }
1548
1549 /* Finally, allocate space. */
1550 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1551 {
1552 asection *sreloc = elf_section_data (p->sec)->sreloc;
1553 sreloc->_raw_size += p->count * sizeof (Elf64_External_Rela);
1554 }
1555
1556 return TRUE;
1557 }
1558
1559 /* Find any dynamic relocs that apply to read-only sections. */
1560
1561 static bfd_boolean
1562 readonly_dynrelocs (h, inf)
1563 struct elf_link_hash_entry *h;
1564 PTR inf;
1565 {
1566 struct elf64_x86_64_link_hash_entry *eh;
1567 struct elf64_x86_64_dyn_relocs *p;
1568
1569 if (h->root.type == bfd_link_hash_warning)
1570 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1571
1572 eh = (struct elf64_x86_64_link_hash_entry *) h;
1573 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1574 {
1575 asection *s = p->sec->output_section;
1576
1577 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1578 {
1579 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1580
1581 info->flags |= DF_TEXTREL;
1582
1583 /* Not an error, just cut short the traversal. */
1584 return FALSE;
1585 }
1586 }
1587 return TRUE;
1588 }
1589
1590 /* Set the sizes of the dynamic sections. */
1591
1592 static bfd_boolean
1593 elf64_x86_64_size_dynamic_sections (output_bfd, info)
1594 bfd *output_bfd ATTRIBUTE_UNUSED;
1595 struct bfd_link_info *info;
1596 {
1597 struct elf64_x86_64_link_hash_table *htab;
1598 bfd *dynobj;
1599 asection *s;
1600 bfd_boolean relocs;
1601 bfd *ibfd;
1602
1603 htab = elf64_x86_64_hash_table (info);
1604 dynobj = htab->elf.dynobj;
1605 if (dynobj == NULL)
1606 abort ();
1607
1608 if (htab->elf.dynamic_sections_created)
1609 {
1610 /* Set the contents of the .interp section to the interpreter. */
1611 if (! info->shared)
1612 {
1613 s = bfd_get_section_by_name (dynobj, ".interp");
1614 if (s == NULL)
1615 abort ();
1616 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
1617 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1618 }
1619 }
1620
1621 /* Set up .got offsets for local syms, and space for local dynamic
1622 relocs. */
1623 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1624 {
1625 bfd_signed_vma *local_got;
1626 bfd_signed_vma *end_local_got;
1627 char *local_tls_type;
1628 bfd_size_type locsymcount;
1629 Elf_Internal_Shdr *symtab_hdr;
1630 asection *srel;
1631
1632 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1633 continue;
1634
1635 for (s = ibfd->sections; s != NULL; s = s->next)
1636 {
1637 struct elf64_x86_64_dyn_relocs *p;
1638
1639 for (p = *((struct elf64_x86_64_dyn_relocs **)
1640 &elf_section_data (s)->local_dynrel);
1641 p != NULL;
1642 p = p->next)
1643 {
1644 if (!bfd_is_abs_section (p->sec)
1645 && bfd_is_abs_section (p->sec->output_section))
1646 {
1647 /* Input section has been discarded, either because
1648 it is a copy of a linkonce section or due to
1649 linker script /DISCARD/, so we'll be discarding
1650 the relocs too. */
1651 }
1652 else if (p->count != 0)
1653 {
1654 srel = elf_section_data (p->sec)->sreloc;
1655 srel->_raw_size += p->count * sizeof (Elf64_External_Rela);
1656 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1657 info->flags |= DF_TEXTREL;
1658
1659 }
1660 }
1661 }
1662
1663 local_got = elf_local_got_refcounts (ibfd);
1664 if (!local_got)
1665 continue;
1666
1667 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1668 locsymcount = symtab_hdr->sh_info;
1669 end_local_got = local_got + locsymcount;
1670 local_tls_type = elf64_x86_64_local_got_tls_type (ibfd);
1671 s = htab->sgot;
1672 srel = htab->srelgot;
1673 for (; local_got < end_local_got; ++local_got, ++local_tls_type)
1674 {
1675 if (*local_got > 0)
1676 {
1677 *local_got = s->_raw_size;
1678 s->_raw_size += GOT_ENTRY_SIZE;
1679 if (*local_tls_type == GOT_TLS_GD)
1680 s->_raw_size += GOT_ENTRY_SIZE;
1681 if (info->shared
1682 || *local_tls_type == GOT_TLS_GD
1683 || *local_tls_type == GOT_TLS_IE)
1684 srel->_raw_size += sizeof (Elf64_External_Rela);
1685 }
1686 else
1687 *local_got = (bfd_vma) -1;
1688 }
1689 }
1690
1691 if (htab->tls_ld_got.refcount > 0)
1692 {
1693 /* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD
1694 relocs. */
1695 htab->tls_ld_got.offset = htab->sgot->_raw_size;
1696 htab->sgot->_raw_size += 2 * GOT_ENTRY_SIZE;
1697 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1698 }
1699 else
1700 htab->tls_ld_got.offset = -1;
1701
1702 /* Allocate global sym .plt and .got entries, and space for global
1703 sym dynamic relocs. */
1704 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1705
1706 /* We now have determined the sizes of the various dynamic sections.
1707 Allocate memory for them. */
1708 relocs = FALSE;
1709 for (s = dynobj->sections; s != NULL; s = s->next)
1710 {
1711 if ((s->flags & SEC_LINKER_CREATED) == 0)
1712 continue;
1713
1714 if (s == htab->splt
1715 || s == htab->sgot
1716 || s == htab->sgotplt)
1717 {
1718 /* Strip this section if we don't need it; see the
1719 comment below. */
1720 }
1721 else if (strncmp (bfd_get_section_name (dynobj, s), ".rela", 5) == 0)
1722 {
1723 if (s->_raw_size != 0 && s != htab->srelplt)
1724 relocs = TRUE;
1725
1726 /* We use the reloc_count field as a counter if we need
1727 to copy relocs into the output file. */
1728 s->reloc_count = 0;
1729 }
1730 else
1731 {
1732 /* It's not one of our sections, so don't allocate space. */
1733 continue;
1734 }
1735
1736 if (s->_raw_size == 0)
1737 {
1738 /* If we don't need this section, strip it from the
1739 output file. This is mostly to handle .rela.bss and
1740 .rela.plt. We must create both sections in
1741 create_dynamic_sections, because they must be created
1742 before the linker maps input sections to output
1743 sections. The linker does that before
1744 adjust_dynamic_symbol is called, and it is that
1745 function which decides whether anything needs to go
1746 into these sections. */
1747
1748 _bfd_strip_section_from_output (info, s);
1749 continue;
1750 }
1751
1752 /* Allocate memory for the section contents. We use bfd_zalloc
1753 here in case unused entries are not reclaimed before the
1754 section's contents are written out. This should not happen,
1755 but this way if it does, we get a R_X86_64_NONE reloc instead
1756 of garbage. */
1757 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
1758 if (s->contents == NULL)
1759 return FALSE;
1760 }
1761
1762 if (htab->elf.dynamic_sections_created)
1763 {
1764 /* Add some entries to the .dynamic section. We fill in the
1765 values later, in elf64_x86_64_finish_dynamic_sections, but we
1766 must add the entries now so that we get the correct size for
1767 the .dynamic section. The DT_DEBUG entry is filled in by the
1768 dynamic linker and used by the debugger. */
1769 #define add_dynamic_entry(TAG, VAL) \
1770 bfd_elf64_add_dynamic_entry (info, (bfd_vma) (TAG), (bfd_vma) (VAL))
1771
1772 if (! info->shared)
1773 {
1774 if (!add_dynamic_entry (DT_DEBUG, 0))
1775 return FALSE;
1776 }
1777
1778 if (htab->splt->_raw_size != 0)
1779 {
1780 if (!add_dynamic_entry (DT_PLTGOT, 0)
1781 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1782 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1783 || !add_dynamic_entry (DT_JMPREL, 0))
1784 return FALSE;
1785 }
1786
1787 if (relocs)
1788 {
1789 if (!add_dynamic_entry (DT_RELA, 0)
1790 || !add_dynamic_entry (DT_RELASZ, 0)
1791 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
1792 return FALSE;
1793
1794 /* If any dynamic relocs apply to a read-only section,
1795 then we need a DT_TEXTREL entry. */
1796 if ((info->flags & DF_TEXTREL) == 0)
1797 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
1798 (PTR) info);
1799
1800 if ((info->flags & DF_TEXTREL) != 0)
1801 {
1802 if (!add_dynamic_entry (DT_TEXTREL, 0))
1803 return FALSE;
1804 }
1805 }
1806 }
1807 #undef add_dynamic_entry
1808
1809 return TRUE;
1810 }
1811
1812 /* Return the base VMA address which should be subtracted from real addresses
1813 when resolving @dtpoff relocation.
1814 This is PT_TLS segment p_vaddr. */
1815
1816 static bfd_vma
1817 dtpoff_base (info)
1818 struct bfd_link_info *info;
1819 {
1820 /* If tls_segment is NULL, we should have signalled an error already. */
1821 if (elf_hash_table (info)->tls_segment == NULL)
1822 return 0;
1823 return elf_hash_table (info)->tls_segment->start;
1824 }
1825
1826 /* Return the relocation value for @tpoff relocation
1827 if STT_TLS virtual address is ADDRESS. */
1828
1829 static bfd_vma
1830 tpoff (info, address)
1831 struct bfd_link_info *info;
1832 bfd_vma address;
1833 {
1834 struct elf_link_tls_segment *tls_segment
1835 = elf_hash_table (info)->tls_segment;
1836
1837 /* If tls_segment is NULL, we should have signalled an error already. */
1838 if (tls_segment == NULL)
1839 return 0;
1840 return address - align_power (tls_segment->size, tls_segment->align)
1841 - tls_segment->start;
1842 }
1843
1844 /* Relocate an x86_64 ELF section. */
1845
1846 static bfd_boolean
1847 elf64_x86_64_relocate_section (output_bfd, info, input_bfd, input_section,
1848 contents, relocs, local_syms, local_sections)
1849 bfd *output_bfd;
1850 struct bfd_link_info *info;
1851 bfd *input_bfd;
1852 asection *input_section;
1853 bfd_byte *contents;
1854 Elf_Internal_Rela *relocs;
1855 Elf_Internal_Sym *local_syms;
1856 asection **local_sections;
1857 {
1858 struct elf64_x86_64_link_hash_table *htab;
1859 Elf_Internal_Shdr *symtab_hdr;
1860 struct elf_link_hash_entry **sym_hashes;
1861 bfd_vma *local_got_offsets;
1862 Elf_Internal_Rela *rel;
1863 Elf_Internal_Rela *relend;
1864
1865 if (info->relocateable)
1866 return TRUE;
1867
1868 htab = elf64_x86_64_hash_table (info);
1869 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1870 sym_hashes = elf_sym_hashes (input_bfd);
1871 local_got_offsets = elf_local_got_offsets (input_bfd);
1872
1873 rel = relocs;
1874 relend = relocs + input_section->reloc_count;
1875 for (; rel < relend; rel++)
1876 {
1877 unsigned int r_type;
1878 reloc_howto_type *howto;
1879 unsigned long r_symndx;
1880 struct elf_link_hash_entry *h;
1881 Elf_Internal_Sym *sym;
1882 asection *sec;
1883 bfd_vma off;
1884 bfd_vma relocation;
1885 bfd_boolean unresolved_reloc;
1886 bfd_reloc_status_type r;
1887 int tls_type;
1888
1889 r_type = ELF64_R_TYPE (rel->r_info);
1890 if (r_type == (int) R_X86_64_GNU_VTINHERIT
1891 || r_type == (int) R_X86_64_GNU_VTENTRY)
1892 continue;
1893
1894 if (r_type >= R_X86_64_max)
1895 {
1896 bfd_set_error (bfd_error_bad_value);
1897 return FALSE;
1898 }
1899
1900 howto = x86_64_elf_howto_table + r_type;
1901 r_symndx = ELF64_R_SYM (rel->r_info);
1902 h = NULL;
1903 sym = NULL;
1904 sec = NULL;
1905 unresolved_reloc = FALSE;
1906 if (r_symndx < symtab_hdr->sh_info)
1907 {
1908 sym = local_syms + r_symndx;
1909 sec = local_sections[r_symndx];
1910
1911 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, sec, rel);
1912 }
1913 else
1914 {
1915 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1916 while (h->root.type == bfd_link_hash_indirect
1917 || h->root.type == bfd_link_hash_warning)
1918 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1919
1920 if (h->root.type == bfd_link_hash_defined
1921 || h->root.type == bfd_link_hash_defweak)
1922 {
1923 sec = h->root.u.def.section;
1924 if (sec->output_section == NULL)
1925 {
1926 /* Set a flag that will be cleared later if we find a
1927 relocation value for this symbol. output_section
1928 is typically NULL for symbols satisfied by a shared
1929 library. */
1930 unresolved_reloc = TRUE;
1931 relocation = 0;
1932 }
1933 else
1934 relocation = (h->root.u.def.value
1935 + sec->output_section->vma
1936 + sec->output_offset);
1937 }
1938 else if (h->root.type == bfd_link_hash_undefweak)
1939 relocation = 0;
1940 else if (info->shared
1941 && !info->no_undefined
1942 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
1943 relocation = 0;
1944 else
1945 {
1946 if (! ((*info->callbacks->undefined_symbol)
1947 (info, h->root.root.string, input_bfd,
1948 input_section, rel->r_offset,
1949 (!info->shared || info->no_undefined
1950 || ELF_ST_VISIBILITY (h->other)))))
1951 return FALSE;
1952 relocation = 0;
1953 }
1954 }
1955 /* When generating a shared object, the relocations handled here are
1956 copied into the output file to be resolved at run time. */
1957 switch (r_type)
1958 {
1959 case R_X86_64_GOT32:
1960 /* Relocation is to the entry for this symbol in the global
1961 offset table. */
1962 case R_X86_64_GOTPCREL:
1963 /* Use global offset table as symbol value. */
1964 if (htab->sgot == NULL)
1965 abort ();
1966
1967 if (h != NULL)
1968 {
1969 bfd_boolean dyn;
1970
1971 off = h->got.offset;
1972 dyn = htab->elf.dynamic_sections_created;
1973
1974 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h)
1975 || (info->shared
1976 && (info->symbolic
1977 || h->dynindx == -1
1978 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
1979 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1980 {
1981 /* This is actually a static link, or it is a -Bsymbolic
1982 link and the symbol is defined locally, or the symbol
1983 was forced to be local because of a version file. We
1984 must initialize this entry in the global offset table.
1985 Since the offset must always be a multiple of 8, we
1986 use the least significant bit to record whether we
1987 have initialized it already.
1988
1989 When doing a dynamic link, we create a .rela.got
1990 relocation entry to initialize the value. This is
1991 done in the finish_dynamic_symbol routine. */
1992 if ((off & 1) != 0)
1993 off &= ~1;
1994 else
1995 {
1996 bfd_put_64 (output_bfd, relocation,
1997 htab->sgot->contents + off);
1998 h->got.offset |= 1;
1999 }
2000 }
2001 else
2002 unresolved_reloc = FALSE;
2003 }
2004 else
2005 {
2006 if (local_got_offsets == NULL)
2007 abort ();
2008
2009 off = local_got_offsets[r_symndx];
2010
2011 /* The offset must always be a multiple of 8. We use
2012 the least significant bit to record whether we have
2013 already generated the necessary reloc. */
2014 if ((off & 1) != 0)
2015 off &= ~1;
2016 else
2017 {
2018 bfd_put_64 (output_bfd, relocation,
2019 htab->sgot->contents + off);
2020
2021 if (info->shared)
2022 {
2023 asection *s;
2024 Elf_Internal_Rela outrel;
2025 bfd_byte *loc;
2026
2027 /* We need to generate a R_X86_64_RELATIVE reloc
2028 for the dynamic linker. */
2029 s = htab->srelgot;
2030 if (s == NULL)
2031 abort ();
2032
2033 outrel.r_offset = (htab->sgot->output_section->vma
2034 + htab->sgot->output_offset
2035 + off);
2036 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2037 outrel.r_addend = relocation;
2038 loc = s->contents;
2039 loc += s->reloc_count++ * sizeof (Elf64_External_Rela);
2040 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2041 }
2042
2043 local_got_offsets[r_symndx] |= 1;
2044 }
2045 }
2046
2047 if (off >= (bfd_vma) -2)
2048 abort ();
2049
2050 relocation = htab->sgot->output_offset + off;
2051 if (r_type == R_X86_64_GOTPCREL)
2052 relocation += htab->sgot->output_section->vma;
2053
2054 break;
2055
2056 case R_X86_64_PLT32:
2057 /* Relocation is to the entry for this symbol in the
2058 procedure linkage table. */
2059
2060 /* Resolve a PLT32 reloc against a local symbol directly,
2061 without using the procedure linkage table. */
2062 if (h == NULL)
2063 break;
2064
2065 if (h->plt.offset == (bfd_vma) -1
2066 || htab->splt == NULL)
2067 {
2068 /* We didn't make a PLT entry for this symbol. This
2069 happens when statically linking PIC code, or when
2070 using -Bsymbolic. */
2071 break;
2072 }
2073
2074 relocation = (htab->splt->output_section->vma
2075 + htab->splt->output_offset
2076 + h->plt.offset);
2077 unresolved_reloc = FALSE;
2078 break;
2079
2080 case R_X86_64_PC8:
2081 case R_X86_64_PC16:
2082 case R_X86_64_PC32:
2083 case R_X86_64_8:
2084 case R_X86_64_16:
2085 case R_X86_64_32:
2086 case R_X86_64_64:
2087 /* FIXME: The ABI says the linker should make sure the value is
2088 the same when it's zeroextended to 64 bit. */
2089
2090 /* r_symndx will be zero only for relocs against symbols
2091 from removed linkonce sections, or sections discarded by
2092 a linker script. */
2093 if (r_symndx == 0
2094 || (input_section->flags & SEC_ALLOC) == 0)
2095 break;
2096
2097 if ((info->shared
2098 && ((r_type != R_X86_64_PC8
2099 && r_type != R_X86_64_PC16
2100 && r_type != R_X86_64_PC32)
2101 || (h != NULL
2102 && h->dynindx != -1
2103 && (! info->symbolic
2104 || (h->elf_link_hash_flags
2105 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
2106 || (ELIMINATE_COPY_RELOCS
2107 && !info->shared
2108 && h != NULL
2109 && h->dynindx != -1
2110 && (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
2111 && (((h->elf_link_hash_flags
2112 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2113 && (h->elf_link_hash_flags
2114 & ELF_LINK_HASH_DEF_REGULAR) == 0)
2115 || h->root.type == bfd_link_hash_undefweak
2116 || h->root.type == bfd_link_hash_undefined)))
2117 {
2118 Elf_Internal_Rela outrel;
2119 bfd_byte *loc;
2120 bfd_boolean skip, relocate;
2121 asection *sreloc;
2122
2123 /* When generating a shared object, these relocations
2124 are copied into the output file to be resolved at run
2125 time. */
2126 skip = FALSE;
2127 relocate = FALSE;
2128
2129 outrel.r_offset =
2130 _bfd_elf_section_offset (output_bfd, info, input_section,
2131 rel->r_offset);
2132 if (outrel.r_offset == (bfd_vma) -1)
2133 skip = TRUE;
2134 else if (outrel.r_offset == (bfd_vma) -2)
2135 skip = TRUE, relocate = TRUE;
2136
2137 outrel.r_offset += (input_section->output_section->vma
2138 + input_section->output_offset);
2139
2140 if (skip)
2141 memset (&outrel, 0, sizeof outrel);
2142
2143 /* h->dynindx may be -1 if this symbol was marked to
2144 become local. */
2145 else if (h != NULL
2146 && h->dynindx != -1
2147 && (r_type == R_X86_64_PC8
2148 || r_type == R_X86_64_PC16
2149 || r_type == R_X86_64_PC32
2150 || !info->shared
2151 || !info->symbolic
2152 || (h->elf_link_hash_flags
2153 & ELF_LINK_HASH_DEF_REGULAR) == 0))
2154 {
2155 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
2156 outrel.r_addend = rel->r_addend;
2157 }
2158 else
2159 {
2160 /* This symbol is local, or marked to become local. */
2161 if (r_type == R_X86_64_64)
2162 {
2163 relocate = TRUE;
2164 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2165 outrel.r_addend = relocation + rel->r_addend;
2166 }
2167 else
2168 {
2169 long sindx;
2170
2171 if (h == NULL)
2172 sec = local_sections[r_symndx];
2173 else
2174 {
2175 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2176 || (h->root.type
2177 == bfd_link_hash_defweak));
2178 sec = h->root.u.def.section;
2179 }
2180 if (sec != NULL && bfd_is_abs_section (sec))
2181 sindx = 0;
2182 else if (sec == NULL || sec->owner == NULL)
2183 {
2184 bfd_set_error (bfd_error_bad_value);
2185 return FALSE;
2186 }
2187 else
2188 {
2189 asection *osec;
2190
2191 osec = sec->output_section;
2192 sindx = elf_section_data (osec)->dynindx;
2193 BFD_ASSERT (sindx > 0);
2194 }
2195
2196 outrel.r_info = ELF64_R_INFO (sindx, r_type);
2197 outrel.r_addend = relocation + rel->r_addend;
2198 }
2199 }
2200
2201 sreloc = elf_section_data (input_section)->sreloc;
2202 if (sreloc == NULL)
2203 abort ();
2204
2205 loc = sreloc->contents;
2206 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
2207 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2208
2209 /* If this reloc is against an external symbol, we do
2210 not want to fiddle with the addend. Otherwise, we
2211 need to include the symbol value so that it becomes
2212 an addend for the dynamic reloc. */
2213 if (! relocate)
2214 continue;
2215 }
2216
2217 break;
2218
2219 case R_X86_64_TLSGD:
2220 case R_X86_64_GOTTPOFF:
2221 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
2222 tls_type = GOT_UNKNOWN;
2223 if (h == NULL && local_got_offsets)
2224 tls_type = elf64_x86_64_local_got_tls_type (input_bfd) [r_symndx];
2225 else if (h != NULL)
2226 {
2227 tls_type = elf64_x86_64_hash_entry (h)->tls_type;
2228 if (!info->shared && h->dynindx == -1 && tls_type == GOT_TLS_IE)
2229 r_type = R_X86_64_TPOFF32;
2230 }
2231 if (r_type == R_X86_64_TLSGD)
2232 {
2233 if (tls_type == GOT_TLS_IE)
2234 r_type = R_X86_64_GOTTPOFF;
2235 }
2236
2237 if (r_type == R_X86_64_TPOFF32)
2238 {
2239 BFD_ASSERT (! unresolved_reloc);
2240 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
2241 {
2242 unsigned int i;
2243 static unsigned char tlsgd[8]
2244 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2245
2246 /* GD->LE transition.
2247 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2248 .word 0x6666; rex64; call __tls_get_addr@plt
2249 Change it into:
2250 movq %fs:0, %rax
2251 leaq foo@tpoff(%rax), %rax */
2252 BFD_ASSERT (rel->r_offset >= 4);
2253 for (i = 0; i < 4; i++)
2254 BFD_ASSERT (bfd_get_8 (input_bfd,
2255 contents + rel->r_offset - 4 + i)
2256 == tlsgd[i]);
2257 BFD_ASSERT (rel->r_offset + 12 <= input_section->_raw_size);
2258 for (i = 0; i < 4; i++)
2259 BFD_ASSERT (bfd_get_8 (input_bfd,
2260 contents + rel->r_offset + 4 + i)
2261 == tlsgd[i+4]);
2262 BFD_ASSERT (rel + 1 < relend);
2263 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2264 memcpy (contents + rel->r_offset - 4,
2265 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0",
2266 16);
2267 bfd_put_32 (output_bfd, tpoff (info, relocation),
2268 contents + rel->r_offset + 8);
2269 /* Skip R_X86_64_PLT32. */
2270 rel++;
2271 continue;
2272 }
2273 else
2274 {
2275 unsigned int val, type, reg;
2276
2277 /* IE->LE transition:
2278 Originally it can be one of:
2279 movq foo@gottpoff(%rip), %reg
2280 addq foo@gottpoff(%rip), %reg
2281 We change it into:
2282 movq $foo, %reg
2283 leaq foo(%reg), %reg
2284 addq $foo, %reg. */
2285 BFD_ASSERT (rel->r_offset >= 3);
2286 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 3);
2287 BFD_ASSERT (val == 0x48 || val == 0x4c);
2288 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2289 BFD_ASSERT (type == 0x8b || type == 0x03);
2290 reg = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2291 BFD_ASSERT ((reg & 0xc7) == 5);
2292 reg >>= 3;
2293 BFD_ASSERT (rel->r_offset + 4 <= input_section->_raw_size);
2294 if (type == 0x8b)
2295 {
2296 /* movq */
2297 if (val == 0x4c)
2298 bfd_put_8 (output_bfd, 0x49,
2299 contents + rel->r_offset - 3);
2300 bfd_put_8 (output_bfd, 0xc7,
2301 contents + rel->r_offset - 2);
2302 bfd_put_8 (output_bfd, 0xc0 | reg,
2303 contents + rel->r_offset - 1);
2304 }
2305 else if (reg == 4)
2306 {
2307 /* addq -> addq - addressing with %rsp/%r12 is
2308 special */
2309 if (val == 0x4c)
2310 bfd_put_8 (output_bfd, 0x49,
2311 contents + rel->r_offset - 3);
2312 bfd_put_8 (output_bfd, 0x81,
2313 contents + rel->r_offset - 2);
2314 bfd_put_8 (output_bfd, 0xc0 | reg,
2315 contents + rel->r_offset - 1);
2316 }
2317 else
2318 {
2319 /* addq -> leaq */
2320 if (val == 0x4c)
2321 bfd_put_8 (output_bfd, 0x4d,
2322 contents + rel->r_offset - 3);
2323 bfd_put_8 (output_bfd, 0x8d,
2324 contents + rel->r_offset - 2);
2325 bfd_put_8 (output_bfd, 0x80 | reg | (reg << 3),
2326 contents + rel->r_offset - 1);
2327 }
2328 bfd_put_32 (output_bfd, tpoff (info, relocation),
2329 contents + rel->r_offset);
2330 continue;
2331 }
2332 }
2333
2334 if (htab->sgot == NULL)
2335 abort ();
2336
2337 if (h != NULL)
2338 off = h->got.offset;
2339 else
2340 {
2341 if (local_got_offsets == NULL)
2342 abort ();
2343
2344 off = local_got_offsets[r_symndx];
2345 }
2346
2347 if ((off & 1) != 0)
2348 off &= ~1;
2349 else
2350 {
2351 Elf_Internal_Rela outrel;
2352 bfd_byte *loc;
2353 int dr_type, indx;
2354
2355 if (htab->srelgot == NULL)
2356 abort ();
2357
2358 outrel.r_offset = (htab->sgot->output_section->vma
2359 + htab->sgot->output_offset + off);
2360
2361 indx = h && h->dynindx != -1 ? h->dynindx : 0;
2362 if (r_type == R_X86_64_TLSGD)
2363 dr_type = R_X86_64_DTPMOD64;
2364 else
2365 dr_type = R_X86_64_TPOFF64;
2366
2367 bfd_put_64 (output_bfd, 0, htab->sgot->contents + off);
2368 outrel.r_addend = 0;
2369 if (dr_type == R_X86_64_TPOFF64 && indx == 0)
2370 outrel.r_addend = relocation - dtpoff_base (info);
2371 outrel.r_info = ELF64_R_INFO (indx, dr_type);
2372
2373 loc = htab->srelgot->contents;
2374 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2375 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2376
2377 if (r_type == R_X86_64_TLSGD)
2378 {
2379 if (indx == 0)
2380 {
2381 BFD_ASSERT (! unresolved_reloc);
2382 bfd_put_64 (output_bfd,
2383 relocation - dtpoff_base (info),
2384 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2385 }
2386 else
2387 {
2388 bfd_put_64 (output_bfd, 0,
2389 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2390 outrel.r_info = ELF64_R_INFO (indx,
2391 R_X86_64_DTPOFF64);
2392 outrel.r_offset += GOT_ENTRY_SIZE;
2393 htab->srelgot->reloc_count++;
2394 loc += sizeof (Elf64_External_Rela);
2395 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2396 }
2397 }
2398
2399 if (h != NULL)
2400 h->got.offset |= 1;
2401 else
2402 local_got_offsets[r_symndx] |= 1;
2403 }
2404
2405 if (off >= (bfd_vma) -2)
2406 abort ();
2407 if (r_type == ELF64_R_TYPE (rel->r_info))
2408 {
2409 relocation = htab->sgot->output_section->vma
2410 + htab->sgot->output_offset + off;
2411 unresolved_reloc = FALSE;
2412 }
2413 else
2414 {
2415 unsigned int i;
2416 static unsigned char tlsgd[8]
2417 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2418
2419 /* GD->IE transition.
2420 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2421 .word 0x6666; rex64; call __tls_get_addr@plt
2422 Change it into:
2423 movq %fs:0, %rax
2424 addq foo@gottpoff(%rip), %rax */
2425 BFD_ASSERT (rel->r_offset >= 4);
2426 for (i = 0; i < 4; i++)
2427 BFD_ASSERT (bfd_get_8 (input_bfd,
2428 contents + rel->r_offset - 4 + i)
2429 == tlsgd[i]);
2430 BFD_ASSERT (rel->r_offset + 12 <= input_section->_raw_size);
2431 for (i = 0; i < 4; i++)
2432 BFD_ASSERT (bfd_get_8 (input_bfd,
2433 contents + rel->r_offset + 4 + i)
2434 == tlsgd[i+4]);
2435 BFD_ASSERT (rel + 1 < relend);
2436 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2437 memcpy (contents + rel->r_offset - 4,
2438 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0",
2439 16);
2440
2441 relocation = (htab->sgot->output_section->vma
2442 + htab->sgot->output_offset + off
2443 - rel->r_offset
2444 - input_section->output_section->vma
2445 - input_section->output_offset
2446 - 12);
2447 bfd_put_32 (output_bfd, relocation,
2448 contents + rel->r_offset + 8);
2449 /* Skip R_X86_64_PLT32. */
2450 rel++;
2451 continue;
2452 }
2453 break;
2454
2455 case R_X86_64_TLSLD:
2456 if (! info->shared)
2457 {
2458 /* LD->LE transition:
2459 Ensure it is:
2460 leaq foo@tlsld(%rip), %rdi; call __tls_get_addr@plt.
2461 We change it into:
2462 .word 0x6666; .byte 0x66; movl %fs:0, %rax. */
2463 BFD_ASSERT (rel->r_offset >= 3);
2464 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 3)
2465 == 0x48);
2466 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 2)
2467 == 0x8d);
2468 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 1)
2469 == 0x3d);
2470 BFD_ASSERT (rel->r_offset + 9 <= input_section->_raw_size);
2471 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2472 == 0xe8);
2473 BFD_ASSERT (rel + 1 < relend);
2474 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2475 memcpy (contents + rel->r_offset - 3,
2476 "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0", 12);
2477 /* Skip R_X86_64_PLT32. */
2478 rel++;
2479 continue;
2480 }
2481
2482 if (htab->sgot == NULL)
2483 abort ();
2484
2485 off = htab->tls_ld_got.offset;
2486 if (off & 1)
2487 off &= ~1;
2488 else
2489 {
2490 Elf_Internal_Rela outrel;
2491 bfd_byte *loc;
2492
2493 if (htab->srelgot == NULL)
2494 abort ();
2495
2496 outrel.r_offset = (htab->sgot->output_section->vma
2497 + htab->sgot->output_offset + off);
2498
2499 bfd_put_64 (output_bfd, 0,
2500 htab->sgot->contents + off);
2501 bfd_put_64 (output_bfd, 0,
2502 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2503 outrel.r_info = ELF64_R_INFO (0, R_X86_64_DTPMOD64);
2504 outrel.r_addend = 0;
2505 loc = htab->srelgot->contents;
2506 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2507 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2508 htab->tls_ld_got.offset |= 1;
2509 }
2510 relocation = htab->sgot->output_section->vma
2511 + htab->sgot->output_offset + off;
2512 unresolved_reloc = FALSE;
2513 break;
2514
2515 case R_X86_64_DTPOFF32:
2516 if (info->shared || (input_section->flags & SEC_CODE) == 0)
2517 relocation -= dtpoff_base (info);
2518 else
2519 relocation = tpoff (info, relocation);
2520 break;
2521
2522 case R_X86_64_TPOFF32:
2523 BFD_ASSERT (! info->shared);
2524 relocation = tpoff (info, relocation);
2525 break;
2526
2527 default:
2528 break;
2529 }
2530
2531 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
2532 because such sections are not SEC_ALLOC and thus ld.so will
2533 not process them. */
2534 if (unresolved_reloc
2535 && !((input_section->flags & SEC_DEBUGGING) != 0
2536 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
2537 (*_bfd_error_handler)
2538 (_("%s(%s+0x%lx): unresolvable relocation against symbol `%s'"),
2539 bfd_archive_filename (input_bfd),
2540 bfd_get_section_name (input_bfd, input_section),
2541 (long) rel->r_offset,
2542 h->root.root.string);
2543
2544 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
2545 contents, rel->r_offset,
2546 relocation, rel->r_addend);
2547
2548 if (r != bfd_reloc_ok)
2549 {
2550 const char *name;
2551
2552 if (h != NULL)
2553 name = h->root.root.string;
2554 else
2555 {
2556 name = bfd_elf_string_from_elf_section (input_bfd,
2557 symtab_hdr->sh_link,
2558 sym->st_name);
2559 if (name == NULL)
2560 return FALSE;
2561 if (*name == '\0')
2562 name = bfd_section_name (input_bfd, sec);
2563 }
2564
2565 if (r == bfd_reloc_overflow)
2566 {
2567
2568 if (! ((*info->callbacks->reloc_overflow)
2569 (info, name, howto->name, (bfd_vma) 0,
2570 input_bfd, input_section, rel->r_offset)))
2571 return FALSE;
2572 }
2573 else
2574 {
2575 (*_bfd_error_handler)
2576 (_("%s(%s+0x%lx): reloc against `%s': error %d"),
2577 bfd_archive_filename (input_bfd),
2578 bfd_get_section_name (input_bfd, input_section),
2579 (long) rel->r_offset, name, (int) r);
2580 return FALSE;
2581 }
2582 }
2583 }
2584
2585 return TRUE;
2586 }
2587
2588 /* Finish up dynamic symbol handling. We set the contents of various
2589 dynamic sections here. */
2590
2591 static bfd_boolean
2592 elf64_x86_64_finish_dynamic_symbol (output_bfd, info, h, sym)
2593 bfd *output_bfd;
2594 struct bfd_link_info *info;
2595 struct elf_link_hash_entry *h;
2596 Elf_Internal_Sym *sym;
2597 {
2598 struct elf64_x86_64_link_hash_table *htab;
2599
2600 htab = elf64_x86_64_hash_table (info);
2601
2602 if (h->plt.offset != (bfd_vma) -1)
2603 {
2604 bfd_vma plt_index;
2605 bfd_vma got_offset;
2606 Elf_Internal_Rela rela;
2607 bfd_byte *loc;
2608
2609 /* This symbol has an entry in the procedure linkage table. Set
2610 it up. */
2611 if (h->dynindx == -1
2612 || htab->splt == NULL
2613 || htab->sgotplt == NULL
2614 || htab->srelplt == NULL)
2615 abort ();
2616
2617 /* Get the index in the procedure linkage table which
2618 corresponds to this symbol. This is the index of this symbol
2619 in all the symbols for which we are making plt entries. The
2620 first entry in the procedure linkage table is reserved. */
2621 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2622
2623 /* Get the offset into the .got table of the entry that
2624 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
2625 bytes. The first three are reserved for the dynamic linker. */
2626 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
2627
2628 /* Fill in the entry in the procedure linkage table. */
2629 memcpy (htab->splt->contents + h->plt.offset, elf64_x86_64_plt_entry,
2630 PLT_ENTRY_SIZE);
2631
2632 /* Insert the relocation positions of the plt section. The magic
2633 numbers at the end of the statements are the positions of the
2634 relocations in the plt section. */
2635 /* Put offset for jmp *name@GOTPCREL(%rip), since the
2636 instruction uses 6 bytes, subtract this value. */
2637 bfd_put_32 (output_bfd,
2638 (htab->sgotplt->output_section->vma
2639 + htab->sgotplt->output_offset
2640 + got_offset
2641 - htab->splt->output_section->vma
2642 - htab->splt->output_offset
2643 - h->plt.offset
2644 - 6),
2645 htab->splt->contents + h->plt.offset + 2);
2646 /* Put relocation index. */
2647 bfd_put_32 (output_bfd, plt_index,
2648 htab->splt->contents + h->plt.offset + 7);
2649 /* Put offset for jmp .PLT0. */
2650 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
2651 htab->splt->contents + h->plt.offset + 12);
2652
2653 /* Fill in the entry in the global offset table, initially this
2654 points to the pushq instruction in the PLT which is at offset 6. */
2655 bfd_put_64 (output_bfd, (htab->splt->output_section->vma
2656 + htab->splt->output_offset
2657 + h->plt.offset + 6),
2658 htab->sgotplt->contents + got_offset);
2659
2660 /* Fill in the entry in the .rela.plt section. */
2661 rela.r_offset = (htab->sgotplt->output_section->vma
2662 + htab->sgotplt->output_offset
2663 + got_offset);
2664 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
2665 rela.r_addend = 0;
2666 loc = htab->srelplt->contents + plt_index * sizeof (Elf64_External_Rela);
2667 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2668
2669 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2670 {
2671 /* Mark the symbol as undefined, rather than as defined in
2672 the .plt section. Leave the value alone. This is a clue
2673 for the dynamic linker, to make function pointer
2674 comparisons work between an application and shared
2675 library. */
2676 sym->st_shndx = SHN_UNDEF;
2677 }
2678 }
2679
2680 if (h->got.offset != (bfd_vma) -1
2681 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_GD
2682 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE)
2683 {
2684 Elf_Internal_Rela rela;
2685 bfd_byte *loc;
2686
2687 /* This symbol has an entry in the global offset table. Set it
2688 up. */
2689 if (htab->sgot == NULL || htab->srelgot == NULL)
2690 abort ();
2691
2692 rela.r_offset = (htab->sgot->output_section->vma
2693 + htab->sgot->output_offset
2694 + (h->got.offset &~ (bfd_vma) 1));
2695
2696 /* If this is a static link, or it is a -Bsymbolic link and the
2697 symbol is defined locally or was forced to be local because
2698 of a version file, we just want to emit a RELATIVE reloc.
2699 The entry in the global offset table will already have been
2700 initialized in the relocate_section function. */
2701 if (info->shared
2702 && (info->symbolic
2703 || h->dynindx == -1
2704 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
2705 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
2706 {
2707 BFD_ASSERT((h->got.offset & 1) != 0);
2708 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2709 rela.r_addend = (h->root.u.def.value
2710 + h->root.u.def.section->output_section->vma
2711 + h->root.u.def.section->output_offset);
2712 }
2713 else
2714 {
2715 BFD_ASSERT((h->got.offset & 1) == 0);
2716 bfd_put_64 (output_bfd, (bfd_vma) 0,
2717 htab->sgot->contents + h->got.offset);
2718 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
2719 rela.r_addend = 0;
2720 }
2721
2722 loc = htab->srelgot->contents;
2723 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2724 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2725 }
2726
2727 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
2728 {
2729 Elf_Internal_Rela rela;
2730 bfd_byte *loc;
2731
2732 /* This symbol needs a copy reloc. Set it up. */
2733
2734 if (h->dynindx == -1
2735 || (h->root.type != bfd_link_hash_defined
2736 && h->root.type != bfd_link_hash_defweak)
2737 || htab->srelbss == NULL)
2738 abort ();
2739
2740 rela.r_offset = (h->root.u.def.value
2741 + h->root.u.def.section->output_section->vma
2742 + h->root.u.def.section->output_offset);
2743 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
2744 rela.r_addend = 0;
2745 loc = htab->srelbss->contents;
2746 loc += htab->srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
2747 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2748 }
2749
2750 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
2751 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
2752 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
2753 sym->st_shndx = SHN_ABS;
2754
2755 return TRUE;
2756 }
2757
2758 /* Used to decide how to sort relocs in an optimal manner for the
2759 dynamic linker, before writing them out. */
2760
2761 static enum elf_reloc_type_class
2762 elf64_x86_64_reloc_type_class (rela)
2763 const Elf_Internal_Rela *rela;
2764 {
2765 switch ((int) ELF64_R_TYPE (rela->r_info))
2766 {
2767 case R_X86_64_RELATIVE:
2768 return reloc_class_relative;
2769 case R_X86_64_JUMP_SLOT:
2770 return reloc_class_plt;
2771 case R_X86_64_COPY:
2772 return reloc_class_copy;
2773 default:
2774 return reloc_class_normal;
2775 }
2776 }
2777
2778 /* Finish up the dynamic sections. */
2779
2780 static bfd_boolean
2781 elf64_x86_64_finish_dynamic_sections (output_bfd, info)
2782 bfd *output_bfd;
2783 struct bfd_link_info *info;
2784 {
2785 struct elf64_x86_64_link_hash_table *htab;
2786 bfd *dynobj;
2787 asection *sdyn;
2788
2789 htab = elf64_x86_64_hash_table (info);
2790 dynobj = htab->elf.dynobj;
2791 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2792
2793 if (htab->elf.dynamic_sections_created)
2794 {
2795 Elf64_External_Dyn *dyncon, *dynconend;
2796
2797 if (sdyn == NULL || htab->sgot == NULL)
2798 abort ();
2799
2800 dyncon = (Elf64_External_Dyn *) sdyn->contents;
2801 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
2802 for (; dyncon < dynconend; dyncon++)
2803 {
2804 Elf_Internal_Dyn dyn;
2805 asection *s;
2806
2807 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
2808
2809 switch (dyn.d_tag)
2810 {
2811 default:
2812 continue;
2813
2814 case DT_PLTGOT:
2815 dyn.d_un.d_ptr = htab->sgot->output_section->vma;
2816 break;
2817
2818 case DT_JMPREL:
2819 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
2820 break;
2821
2822 case DT_PLTRELSZ:
2823 s = htab->srelplt->output_section;
2824 if (s->_cooked_size != 0)
2825 dyn.d_un.d_val = s->_cooked_size;
2826 else
2827 dyn.d_un.d_val = s->_raw_size;
2828 break;
2829
2830 case DT_RELASZ:
2831 /* The procedure linkage table relocs (DT_JMPREL) should
2832 not be included in the overall relocs (DT_RELA).
2833 Therefore, we override the DT_RELASZ entry here to
2834 make it not include the JMPREL relocs. Since the
2835 linker script arranges for .rela.plt to follow all
2836 other relocation sections, we don't have to worry
2837 about changing the DT_RELA entry. */
2838 if (htab->srelplt != NULL)
2839 {
2840 s = htab->srelplt->output_section;
2841 if (s->_cooked_size != 0)
2842 dyn.d_un.d_val -= s->_cooked_size;
2843 else
2844 dyn.d_un.d_val -= s->_raw_size;
2845 }
2846 break;
2847 }
2848
2849 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
2850 }
2851
2852 /* Fill in the special first entry in the procedure linkage table. */
2853 if (htab->splt && htab->splt->_raw_size > 0)
2854 {
2855 /* Fill in the first entry in the procedure linkage table. */
2856 memcpy (htab->splt->contents, elf64_x86_64_plt0_entry,
2857 PLT_ENTRY_SIZE);
2858 /* Add offset for pushq GOT+8(%rip), since the instruction
2859 uses 6 bytes subtract this value. */
2860 bfd_put_32 (output_bfd,
2861 (htab->sgotplt->output_section->vma
2862 + htab->sgotplt->output_offset
2863 + 8
2864 - htab->splt->output_section->vma
2865 - htab->splt->output_offset
2866 - 6),
2867 htab->splt->contents + 2);
2868 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
2869 the end of the instruction. */
2870 bfd_put_32 (output_bfd,
2871 (htab->sgotplt->output_section->vma
2872 + htab->sgotplt->output_offset
2873 + 16
2874 - htab->splt->output_section->vma
2875 - htab->splt->output_offset
2876 - 12),
2877 htab->splt->contents + 8);
2878
2879 elf_section_data (htab->splt->output_section)->this_hdr.sh_entsize =
2880 PLT_ENTRY_SIZE;
2881 }
2882 }
2883
2884 if (htab->sgotplt)
2885 {
2886 /* Fill in the first three entries in the global offset table. */
2887 if (htab->sgotplt->_raw_size > 0)
2888 {
2889 /* Set the first entry in the global offset table to the address of
2890 the dynamic section. */
2891 if (sdyn == NULL)
2892 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents);
2893 else
2894 bfd_put_64 (output_bfd,
2895 sdyn->output_section->vma + sdyn->output_offset,
2896 htab->sgotplt->contents);
2897 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
2898 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE);
2899 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE*2);
2900 }
2901
2902 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize =
2903 GOT_ENTRY_SIZE;
2904 }
2905
2906 return TRUE;
2907 }
2908
2909
2910 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
2911 #define TARGET_LITTLE_NAME "elf64-x86-64"
2912 #define ELF_ARCH bfd_arch_i386
2913 #define ELF_MACHINE_CODE EM_X86_64
2914 #define ELF_MAXPAGESIZE 0x100000
2915
2916 #define elf_backend_can_gc_sections 1
2917 #define elf_backend_can_refcount 1
2918 #define elf_backend_want_got_plt 1
2919 #define elf_backend_plt_readonly 1
2920 #define elf_backend_want_plt_sym 0
2921 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
2922 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
2923 #define elf_backend_rela_normal 1
2924
2925 #define elf_info_to_howto elf64_x86_64_info_to_howto
2926
2927 #define bfd_elf64_bfd_link_hash_table_create \
2928 elf64_x86_64_link_hash_table_create
2929 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
2930
2931 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
2932 #define elf_backend_check_relocs elf64_x86_64_check_relocs
2933 #define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol
2934 #define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections
2935 #define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections
2936 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
2937 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
2938 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
2939 #define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus
2940 #define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo
2941 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
2942 #define elf_backend_relocate_section elf64_x86_64_relocate_section
2943 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
2944 #define elf_backend_object_p elf64_x86_64_elf_object_p
2945 #define bfd_elf64_mkobject elf64_x86_64_mkobject
2946
2947 #include "elf64-target.h"
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