041e28519e83e2a567e4e854de0a31308181e628
[deliverable/binutils-gdb.git] / bfd / elf64-x86-64.c
1 /* X86-64 specific support for 64-bit ELF
2 Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
3 Free Software Foundation, Inc.
4 Contributed by Jan Hubicka <jh@suse.cz>.
5
6 This file is part of BFD, the Binary File Descriptor library.
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 MA 02110-1301, USA. */
22
23 #include "sysdep.h"
24 #include "bfd.h"
25 #include "bfdlink.h"
26 #include "libbfd.h"
27 #include "elf-bfd.h"
28 #include "bfd_stdint.h"
29
30 #include "elf/x86-64.h"
31
32 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
33 #define MINUS_ONE (~ (bfd_vma) 0)
34
35 /* The relocation "howto" table. Order of fields:
36 type, rightshift, size, bitsize, pc_relative, bitpos, complain_on_overflow,
37 special_function, name, partial_inplace, src_mask, dst_mask, pcrel_offset. */
38 static reloc_howto_type x86_64_elf_howto_table[] =
39 {
40 HOWTO(R_X86_64_NONE, 0, 0, 0, FALSE, 0, complain_overflow_dont,
41 bfd_elf_generic_reloc, "R_X86_64_NONE", FALSE, 0x00000000, 0x00000000,
42 FALSE),
43 HOWTO(R_X86_64_64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
44 bfd_elf_generic_reloc, "R_X86_64_64", FALSE, MINUS_ONE, MINUS_ONE,
45 FALSE),
46 HOWTO(R_X86_64_PC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
47 bfd_elf_generic_reloc, "R_X86_64_PC32", FALSE, 0xffffffff, 0xffffffff,
48 TRUE),
49 HOWTO(R_X86_64_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
50 bfd_elf_generic_reloc, "R_X86_64_GOT32", FALSE, 0xffffffff, 0xffffffff,
51 FALSE),
52 HOWTO(R_X86_64_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
53 bfd_elf_generic_reloc, "R_X86_64_PLT32", FALSE, 0xffffffff, 0xffffffff,
54 TRUE),
55 HOWTO(R_X86_64_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
56 bfd_elf_generic_reloc, "R_X86_64_COPY", FALSE, 0xffffffff, 0xffffffff,
57 FALSE),
58 HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
59 bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", FALSE, MINUS_ONE,
60 MINUS_ONE, FALSE),
61 HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
62 bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", FALSE, MINUS_ONE,
63 MINUS_ONE, FALSE),
64 HOWTO(R_X86_64_RELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
65 bfd_elf_generic_reloc, "R_X86_64_RELATIVE", FALSE, MINUS_ONE,
66 MINUS_ONE, FALSE),
67 HOWTO(R_X86_64_GOTPCREL, 0, 2, 32, TRUE, 0, complain_overflow_signed,
68 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", FALSE, 0xffffffff,
69 0xffffffff, TRUE),
70 HOWTO(R_X86_64_32, 0, 2, 32, FALSE, 0, complain_overflow_unsigned,
71 bfd_elf_generic_reloc, "R_X86_64_32", FALSE, 0xffffffff, 0xffffffff,
72 FALSE),
73 HOWTO(R_X86_64_32S, 0, 2, 32, FALSE, 0, complain_overflow_signed,
74 bfd_elf_generic_reloc, "R_X86_64_32S", FALSE, 0xffffffff, 0xffffffff,
75 FALSE),
76 HOWTO(R_X86_64_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
77 bfd_elf_generic_reloc, "R_X86_64_16", FALSE, 0xffff, 0xffff, FALSE),
78 HOWTO(R_X86_64_PC16,0, 1, 16, TRUE, 0, complain_overflow_bitfield,
79 bfd_elf_generic_reloc, "R_X86_64_PC16", FALSE, 0xffff, 0xffff, TRUE),
80 HOWTO(R_X86_64_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,
81 bfd_elf_generic_reloc, "R_X86_64_8", FALSE, 0xff, 0xff, FALSE),
82 HOWTO(R_X86_64_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed,
83 bfd_elf_generic_reloc, "R_X86_64_PC8", FALSE, 0xff, 0xff, TRUE),
84 HOWTO(R_X86_64_DTPMOD64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
85 bfd_elf_generic_reloc, "R_X86_64_DTPMOD64", FALSE, MINUS_ONE,
86 MINUS_ONE, FALSE),
87 HOWTO(R_X86_64_DTPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
88 bfd_elf_generic_reloc, "R_X86_64_DTPOFF64", FALSE, MINUS_ONE,
89 MINUS_ONE, FALSE),
90 HOWTO(R_X86_64_TPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
91 bfd_elf_generic_reloc, "R_X86_64_TPOFF64", FALSE, MINUS_ONE,
92 MINUS_ONE, FALSE),
93 HOWTO(R_X86_64_TLSGD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
94 bfd_elf_generic_reloc, "R_X86_64_TLSGD", FALSE, 0xffffffff,
95 0xffffffff, TRUE),
96 HOWTO(R_X86_64_TLSLD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
97 bfd_elf_generic_reloc, "R_X86_64_TLSLD", FALSE, 0xffffffff,
98 0xffffffff, TRUE),
99 HOWTO(R_X86_64_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
100 bfd_elf_generic_reloc, "R_X86_64_DTPOFF32", FALSE, 0xffffffff,
101 0xffffffff, FALSE),
102 HOWTO(R_X86_64_GOTTPOFF, 0, 2, 32, TRUE, 0, complain_overflow_signed,
103 bfd_elf_generic_reloc, "R_X86_64_GOTTPOFF", FALSE, 0xffffffff,
104 0xffffffff, TRUE),
105 HOWTO(R_X86_64_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
106 bfd_elf_generic_reloc, "R_X86_64_TPOFF32", FALSE, 0xffffffff,
107 0xffffffff, FALSE),
108 HOWTO(R_X86_64_PC64, 0, 4, 64, TRUE, 0, complain_overflow_bitfield,
109 bfd_elf_generic_reloc, "R_X86_64_PC64", FALSE, MINUS_ONE, MINUS_ONE,
110 TRUE),
111 HOWTO(R_X86_64_GOTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
112 bfd_elf_generic_reloc, "R_X86_64_GOTOFF64",
113 FALSE, MINUS_ONE, MINUS_ONE, FALSE),
114 HOWTO(R_X86_64_GOTPC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
115 bfd_elf_generic_reloc, "R_X86_64_GOTPC32",
116 FALSE, 0xffffffff, 0xffffffff, TRUE),
117 HOWTO(R_X86_64_GOT64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
118 bfd_elf_generic_reloc, "R_X86_64_GOT64", FALSE, MINUS_ONE, MINUS_ONE,
119 FALSE),
120 HOWTO(R_X86_64_GOTPCREL64, 0, 4, 64, TRUE, 0, complain_overflow_signed,
121 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL64", FALSE, MINUS_ONE,
122 MINUS_ONE, TRUE),
123 HOWTO(R_X86_64_GOTPC64, 0, 4, 64, TRUE, 0, complain_overflow_signed,
124 bfd_elf_generic_reloc, "R_X86_64_GOTPC64",
125 FALSE, MINUS_ONE, MINUS_ONE, TRUE),
126 HOWTO(R_X86_64_GOTPLT64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
127 bfd_elf_generic_reloc, "R_X86_64_GOTPLT64", FALSE, MINUS_ONE,
128 MINUS_ONE, FALSE),
129 HOWTO(R_X86_64_PLTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
130 bfd_elf_generic_reloc, "R_X86_64_PLTOFF64", FALSE, MINUS_ONE,
131 MINUS_ONE, FALSE),
132 EMPTY_HOWTO (32),
133 EMPTY_HOWTO (33),
134 HOWTO(R_X86_64_GOTPC32_TLSDESC, 0, 2, 32, TRUE, 0,
135 complain_overflow_bitfield, bfd_elf_generic_reloc,
136 "R_X86_64_GOTPC32_TLSDESC",
137 FALSE, 0xffffffff, 0xffffffff, TRUE),
138 HOWTO(R_X86_64_TLSDESC_CALL, 0, 0, 0, FALSE, 0,
139 complain_overflow_dont, bfd_elf_generic_reloc,
140 "R_X86_64_TLSDESC_CALL",
141 FALSE, 0, 0, FALSE),
142 HOWTO(R_X86_64_TLSDESC, 0, 4, 64, FALSE, 0,
143 complain_overflow_bitfield, bfd_elf_generic_reloc,
144 "R_X86_64_TLSDESC",
145 FALSE, MINUS_ONE, MINUS_ONE, FALSE),
146 HOWTO(R_X86_64_IRELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
147 bfd_elf_generic_reloc, "R_X86_64_IRELATIVE", FALSE, MINUS_ONE,
148 MINUS_ONE, FALSE),
149
150 /* We have a gap in the reloc numbers here.
151 R_X86_64_standard counts the number up to this point, and
152 R_X86_64_vt_offset is the value to subtract from a reloc type of
153 R_X86_64_GNU_VT* to form an index into this table. */
154 #define R_X86_64_standard (R_X86_64_IRELATIVE + 1)
155 #define R_X86_64_vt_offset (R_X86_64_GNU_VTINHERIT - R_X86_64_standard)
156
157 /* GNU extension to record C++ vtable hierarchy. */
158 HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, FALSE, 0, complain_overflow_dont,
159 NULL, "R_X86_64_GNU_VTINHERIT", FALSE, 0, 0, FALSE),
160
161 /* GNU extension to record C++ vtable member usage. */
162 HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, FALSE, 0, complain_overflow_dont,
163 _bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", FALSE, 0, 0,
164 FALSE)
165 };
166
167 #define IS_X86_64_PCREL_TYPE(TYPE) \
168 ( ((TYPE) == R_X86_64_PC8) \
169 || ((TYPE) == R_X86_64_PC16) \
170 || ((TYPE) == R_X86_64_PC32) \
171 || ((TYPE) == R_X86_64_PC64))
172
173 /* Map BFD relocs to the x86_64 elf relocs. */
174 struct elf_reloc_map
175 {
176 bfd_reloc_code_real_type bfd_reloc_val;
177 unsigned char elf_reloc_val;
178 };
179
180 static const struct elf_reloc_map x86_64_reloc_map[] =
181 {
182 { BFD_RELOC_NONE, R_X86_64_NONE, },
183 { BFD_RELOC_64, R_X86_64_64, },
184 { BFD_RELOC_32_PCREL, R_X86_64_PC32, },
185 { BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,},
186 { BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,},
187 { BFD_RELOC_X86_64_COPY, R_X86_64_COPY, },
188 { BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, },
189 { BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, },
190 { BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, },
191 { BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, },
192 { BFD_RELOC_32, R_X86_64_32, },
193 { BFD_RELOC_X86_64_32S, R_X86_64_32S, },
194 { BFD_RELOC_16, R_X86_64_16, },
195 { BFD_RELOC_16_PCREL, R_X86_64_PC16, },
196 { BFD_RELOC_8, R_X86_64_8, },
197 { BFD_RELOC_8_PCREL, R_X86_64_PC8, },
198 { BFD_RELOC_X86_64_DTPMOD64, R_X86_64_DTPMOD64, },
199 { BFD_RELOC_X86_64_DTPOFF64, R_X86_64_DTPOFF64, },
200 { BFD_RELOC_X86_64_TPOFF64, R_X86_64_TPOFF64, },
201 { BFD_RELOC_X86_64_TLSGD, R_X86_64_TLSGD, },
202 { BFD_RELOC_X86_64_TLSLD, R_X86_64_TLSLD, },
203 { BFD_RELOC_X86_64_DTPOFF32, R_X86_64_DTPOFF32, },
204 { BFD_RELOC_X86_64_GOTTPOFF, R_X86_64_GOTTPOFF, },
205 { BFD_RELOC_X86_64_TPOFF32, R_X86_64_TPOFF32, },
206 { BFD_RELOC_64_PCREL, R_X86_64_PC64, },
207 { BFD_RELOC_X86_64_GOTOFF64, R_X86_64_GOTOFF64, },
208 { BFD_RELOC_X86_64_GOTPC32, R_X86_64_GOTPC32, },
209 { BFD_RELOC_X86_64_GOT64, R_X86_64_GOT64, },
210 { BFD_RELOC_X86_64_GOTPCREL64,R_X86_64_GOTPCREL64, },
211 { BFD_RELOC_X86_64_GOTPC64, R_X86_64_GOTPC64, },
212 { BFD_RELOC_X86_64_GOTPLT64, R_X86_64_GOTPLT64, },
213 { BFD_RELOC_X86_64_PLTOFF64, R_X86_64_PLTOFF64, },
214 { BFD_RELOC_X86_64_GOTPC32_TLSDESC, R_X86_64_GOTPC32_TLSDESC, },
215 { BFD_RELOC_X86_64_TLSDESC_CALL, R_X86_64_TLSDESC_CALL, },
216 { BFD_RELOC_X86_64_TLSDESC, R_X86_64_TLSDESC, },
217 { BFD_RELOC_X86_64_IRELATIVE, R_X86_64_IRELATIVE, },
218 { BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
219 { BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
220 };
221
222 static reloc_howto_type *
223 elf64_x86_64_rtype_to_howto (bfd *abfd, unsigned r_type)
224 {
225 unsigned i;
226
227 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT
228 || r_type >= (unsigned int) R_X86_64_max)
229 {
230 if (r_type >= (unsigned int) R_X86_64_standard)
231 {
232 (*_bfd_error_handler) (_("%B: invalid relocation type %d"),
233 abfd, (int) r_type);
234 r_type = R_X86_64_NONE;
235 }
236 i = r_type;
237 }
238 else
239 i = r_type - (unsigned int) R_X86_64_vt_offset;
240 BFD_ASSERT (x86_64_elf_howto_table[i].type == r_type);
241 return &x86_64_elf_howto_table[i];
242 }
243
244 /* Given a BFD reloc type, return a HOWTO structure. */
245 static reloc_howto_type *
246 elf64_x86_64_reloc_type_lookup (bfd *abfd,
247 bfd_reloc_code_real_type code)
248 {
249 unsigned int i;
250
251 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
252 i++)
253 {
254 if (x86_64_reloc_map[i].bfd_reloc_val == code)
255 return elf64_x86_64_rtype_to_howto (abfd,
256 x86_64_reloc_map[i].elf_reloc_val);
257 }
258 return 0;
259 }
260
261 static reloc_howto_type *
262 elf64_x86_64_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
263 const char *r_name)
264 {
265 unsigned int i;
266
267 for (i = 0;
268 i < (sizeof (x86_64_elf_howto_table)
269 / sizeof (x86_64_elf_howto_table[0]));
270 i++)
271 if (x86_64_elf_howto_table[i].name != NULL
272 && strcasecmp (x86_64_elf_howto_table[i].name, r_name) == 0)
273 return &x86_64_elf_howto_table[i];
274
275 return NULL;
276 }
277
278 /* Given an x86_64 ELF reloc type, fill in an arelent structure. */
279
280 static void
281 elf64_x86_64_info_to_howto (bfd *abfd ATTRIBUTE_UNUSED, arelent *cache_ptr,
282 Elf_Internal_Rela *dst)
283 {
284 unsigned r_type;
285
286 r_type = ELF64_R_TYPE (dst->r_info);
287 cache_ptr->howto = elf64_x86_64_rtype_to_howto (abfd, r_type);
288 BFD_ASSERT (r_type == cache_ptr->howto->type);
289 }
290 \f
291 /* Support for core dump NOTE sections. */
292 static bfd_boolean
293 elf64_x86_64_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
294 {
295 int offset;
296 size_t size;
297
298 switch (note->descsz)
299 {
300 default:
301 return FALSE;
302
303 case 336: /* sizeof(istruct elf_prstatus) on Linux/x86_64 */
304 /* pr_cursig */
305 elf_tdata (abfd)->core_signal
306 = bfd_get_16 (abfd, note->descdata + 12);
307
308 /* pr_pid */
309 elf_tdata (abfd)->core_pid
310 = bfd_get_32 (abfd, note->descdata + 32);
311
312 /* pr_reg */
313 offset = 112;
314 size = 216;
315
316 break;
317 }
318
319 /* Make a ".reg/999" section. */
320 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
321 size, note->descpos + offset);
322 }
323
324 static bfd_boolean
325 elf64_x86_64_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
326 {
327 switch (note->descsz)
328 {
329 default:
330 return FALSE;
331
332 case 136: /* sizeof(struct elf_prpsinfo) on Linux/x86_64 */
333 elf_tdata (abfd)->core_program
334 = _bfd_elfcore_strndup (abfd, note->descdata + 40, 16);
335 elf_tdata (abfd)->core_command
336 = _bfd_elfcore_strndup (abfd, note->descdata + 56, 80);
337 }
338
339 /* Note that for some reason, a spurious space is tacked
340 onto the end of the args in some (at least one anyway)
341 implementations, so strip it off if it exists. */
342
343 {
344 char *command = elf_tdata (abfd)->core_command;
345 int n = strlen (command);
346
347 if (0 < n && command[n - 1] == ' ')
348 command[n - 1] = '\0';
349 }
350
351 return TRUE;
352 }
353 \f
354 /* Functions for the x86-64 ELF linker. */
355
356 /* The name of the dynamic interpreter. This is put in the .interp
357 section. */
358
359 #define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
360
361 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
362 copying dynamic variables from a shared lib into an app's dynbss
363 section, and instead use a dynamic relocation to point into the
364 shared lib. */
365 #define ELIMINATE_COPY_RELOCS 1
366
367 /* The size in bytes of an entry in the global offset table. */
368
369 #define GOT_ENTRY_SIZE 8
370
371 /* The size in bytes of an entry in the procedure linkage table. */
372
373 #define PLT_ENTRY_SIZE 16
374
375 /* The first entry in a procedure linkage table looks like this. See the
376 SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
377
378 static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
379 {
380 0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
381 0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
382 0x0f, 0x1f, 0x40, 0x00 /* nopl 0(%rax) */
383 };
384
385 /* Subsequent entries in a procedure linkage table look like this. */
386
387 static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
388 {
389 0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
390 0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
391 0x68, /* pushq immediate */
392 0, 0, 0, 0, /* replaced with index into relocation table. */
393 0xe9, /* jmp relative */
394 0, 0, 0, 0 /* replaced with offset to start of .plt0. */
395 };
396
397 /* The x86-64 linker needs to keep track of the number of relocs that
398 it decides to copy as dynamic relocs in check_relocs for each symbol.
399 This is so that it can later discard them if they are found to be
400 unnecessary. We store the information in a field extending the
401 regular ELF linker hash table. */
402
403 struct elf64_x86_64_dyn_relocs
404 {
405 /* Next section. */
406 struct elf64_x86_64_dyn_relocs *next;
407
408 /* The input section of the reloc. */
409 asection *sec;
410
411 /* Total number of relocs copied for the input section. */
412 bfd_size_type count;
413
414 /* Number of pc-relative relocs copied for the input section. */
415 bfd_size_type pc_count;
416 };
417
418 /* x86-64 ELF linker hash entry. */
419
420 struct elf64_x86_64_link_hash_entry
421 {
422 struct elf_link_hash_entry elf;
423
424 /* Track dynamic relocs copied for this symbol. */
425 struct elf64_x86_64_dyn_relocs *dyn_relocs;
426
427 #define GOT_UNKNOWN 0
428 #define GOT_NORMAL 1
429 #define GOT_TLS_GD 2
430 #define GOT_TLS_IE 3
431 #define GOT_TLS_GDESC 4
432 #define GOT_TLS_GD_BOTH_P(type) \
433 ((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
434 #define GOT_TLS_GD_P(type) \
435 ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
436 #define GOT_TLS_GDESC_P(type) \
437 ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
438 #define GOT_TLS_GD_ANY_P(type) \
439 (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
440 unsigned char tls_type;
441
442 /* Offset of the GOTPLT entry reserved for the TLS descriptor,
443 starting at the end of the jump table. */
444 bfd_vma tlsdesc_got;
445 };
446
447 #define elf64_x86_64_hash_entry(ent) \
448 ((struct elf64_x86_64_link_hash_entry *)(ent))
449
450 struct elf64_x86_64_obj_tdata
451 {
452 struct elf_obj_tdata root;
453
454 /* tls_type for each local got entry. */
455 char *local_got_tls_type;
456
457 /* GOTPLT entries for TLS descriptors. */
458 bfd_vma *local_tlsdesc_gotent;
459 };
460
461 #define elf64_x86_64_tdata(abfd) \
462 ((struct elf64_x86_64_obj_tdata *) (abfd)->tdata.any)
463
464 #define elf64_x86_64_local_got_tls_type(abfd) \
465 (elf64_x86_64_tdata (abfd)->local_got_tls_type)
466
467 #define elf64_x86_64_local_tlsdesc_gotent(abfd) \
468 (elf64_x86_64_tdata (abfd)->local_tlsdesc_gotent)
469
470 #define is_x86_64_elf(bfd) \
471 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \
472 && elf_tdata (bfd) != NULL \
473 && elf_object_id (bfd) == X86_64_ELF_TDATA)
474
475 static bfd_boolean
476 elf64_x86_64_mkobject (bfd *abfd)
477 {
478 return bfd_elf_allocate_object (abfd, sizeof (struct elf64_x86_64_obj_tdata),
479 X86_64_ELF_TDATA);
480 }
481
482 /* x86-64 ELF linker hash table. */
483
484 struct elf64_x86_64_link_hash_table
485 {
486 struct elf_link_hash_table elf;
487
488 /* Short-cuts to get to dynamic linker sections. */
489 asection *sgot;
490 asection *sgotplt;
491 asection *srelgot;
492 asection *splt;
493 asection *srelplt;
494 asection *sdynbss;
495 asection *srelbss;
496 asection *igotplt;
497 asection *iplt;
498 asection *irelplt;
499
500 /* The offset into splt of the PLT entry for the TLS descriptor
501 resolver. Special values are 0, if not necessary (or not found
502 to be necessary yet), and -1 if needed but not determined
503 yet. */
504 bfd_vma tlsdesc_plt;
505 /* The offset into sgot of the GOT entry used by the PLT entry
506 above. */
507 bfd_vma tlsdesc_got;
508
509 union {
510 bfd_signed_vma refcount;
511 bfd_vma offset;
512 } tls_ld_got;
513
514 /* The amount of space used by the jump slots in the GOT. */
515 bfd_vma sgotplt_jump_table_size;
516
517 /* Small local sym to section mapping cache. */
518 struct sym_sec_cache sym_sec;
519
520 /* _TLS_MODULE_BASE_ symbol. */
521 struct bfd_link_hash_entry *tls_module_base;
522 };
523
524 /* Get the x86-64 ELF linker hash table from a link_info structure. */
525
526 #define elf64_x86_64_hash_table(p) \
527 ((struct elf64_x86_64_link_hash_table *) ((p)->hash))
528
529 #define elf64_x86_64_compute_jump_table_size(htab) \
530 ((htab)->srelplt->reloc_count * GOT_ENTRY_SIZE)
531
532 /* Create an entry in an x86-64 ELF linker hash table. */
533
534 static struct bfd_hash_entry *
535 elf64_x86_64_link_hash_newfunc (struct bfd_hash_entry *entry,
536 struct bfd_hash_table *table,
537 const char *string)
538 {
539 /* Allocate the structure if it has not already been allocated by a
540 subclass. */
541 if (entry == NULL)
542 {
543 entry = bfd_hash_allocate (table,
544 sizeof (struct elf64_x86_64_link_hash_entry));
545 if (entry == NULL)
546 return entry;
547 }
548
549 /* Call the allocation method of the superclass. */
550 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
551 if (entry != NULL)
552 {
553 struct elf64_x86_64_link_hash_entry *eh;
554
555 eh = (struct elf64_x86_64_link_hash_entry *) entry;
556 eh->dyn_relocs = NULL;
557 eh->tls_type = GOT_UNKNOWN;
558 eh->tlsdesc_got = (bfd_vma) -1;
559 }
560
561 return entry;
562 }
563
564 /* Create an X86-64 ELF linker hash table. */
565
566 static struct bfd_link_hash_table *
567 elf64_x86_64_link_hash_table_create (bfd *abfd)
568 {
569 struct elf64_x86_64_link_hash_table *ret;
570 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table);
571
572 ret = (struct elf64_x86_64_link_hash_table *) bfd_malloc (amt);
573 if (ret == NULL)
574 return NULL;
575
576 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd,
577 elf64_x86_64_link_hash_newfunc,
578 sizeof (struct elf64_x86_64_link_hash_entry)))
579 {
580 free (ret);
581 return NULL;
582 }
583
584 ret->sgot = NULL;
585 ret->sgotplt = NULL;
586 ret->srelgot = NULL;
587 ret->splt = NULL;
588 ret->srelplt = NULL;
589 ret->sdynbss = NULL;
590 ret->srelbss = NULL;
591 ret->igotplt= NULL;
592 ret->iplt = NULL;
593 ret->irelplt= NULL;
594 ret->sym_sec.abfd = NULL;
595 ret->tlsdesc_plt = 0;
596 ret->tlsdesc_got = 0;
597 ret->tls_ld_got.refcount = 0;
598 ret->sgotplt_jump_table_size = 0;
599 ret->tls_module_base = NULL;
600
601 return &ret->elf.root;
602 }
603
604 /* Create .got, .gotplt, and .rela.got sections in DYNOBJ, and set up
605 shortcuts to them in our hash table. */
606
607 static bfd_boolean
608 elf64_x86_64_create_got_section (bfd *dynobj, struct bfd_link_info *info)
609 {
610 struct elf64_x86_64_link_hash_table *htab;
611
612 if (! _bfd_elf_create_got_section (dynobj, info))
613 return FALSE;
614
615 htab = elf64_x86_64_hash_table (info);
616 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
617 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
618 if (!htab->sgot || !htab->sgotplt)
619 abort ();
620
621 htab->srelgot = bfd_make_section_with_flags (dynobj, ".rela.got",
622 (SEC_ALLOC | SEC_LOAD
623 | SEC_HAS_CONTENTS
624 | SEC_IN_MEMORY
625 | SEC_LINKER_CREATED
626 | SEC_READONLY));
627 if (htab->srelgot == NULL
628 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 3))
629 return FALSE;
630 return TRUE;
631 }
632
633 /* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and
634 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our
635 hash table. */
636
637 static bfd_boolean
638 elf64_x86_64_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info)
639 {
640 struct elf64_x86_64_link_hash_table *htab;
641
642 htab = elf64_x86_64_hash_table (info);
643 if (!htab->sgot && !elf64_x86_64_create_got_section (dynobj, info))
644 return FALSE;
645
646 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
647 return FALSE;
648
649 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
650 htab->srelplt = bfd_get_section_by_name (dynobj, ".rela.plt");
651 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
652 if (!info->shared)
653 htab->srelbss = bfd_get_section_by_name (dynobj, ".rela.bss");
654
655 if (!htab->splt || !htab->srelplt || !htab->sdynbss
656 || (!info->shared && !htab->srelbss))
657 abort ();
658
659 return TRUE;
660 }
661
662 /* Copy the extra info we tack onto an elf_link_hash_entry. */
663
664 static void
665 elf64_x86_64_copy_indirect_symbol (struct bfd_link_info *info,
666 struct elf_link_hash_entry *dir,
667 struct elf_link_hash_entry *ind)
668 {
669 struct elf64_x86_64_link_hash_entry *edir, *eind;
670
671 edir = (struct elf64_x86_64_link_hash_entry *) dir;
672 eind = (struct elf64_x86_64_link_hash_entry *) ind;
673
674 if (eind->dyn_relocs != NULL)
675 {
676 if (edir->dyn_relocs != NULL)
677 {
678 struct elf64_x86_64_dyn_relocs **pp;
679 struct elf64_x86_64_dyn_relocs *p;
680
681 /* Add reloc counts against the indirect sym to the direct sym
682 list. Merge any entries against the same section. */
683 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
684 {
685 struct elf64_x86_64_dyn_relocs *q;
686
687 for (q = edir->dyn_relocs; q != NULL; q = q->next)
688 if (q->sec == p->sec)
689 {
690 q->pc_count += p->pc_count;
691 q->count += p->count;
692 *pp = p->next;
693 break;
694 }
695 if (q == NULL)
696 pp = &p->next;
697 }
698 *pp = edir->dyn_relocs;
699 }
700
701 edir->dyn_relocs = eind->dyn_relocs;
702 eind->dyn_relocs = NULL;
703 }
704
705 if (ind->root.type == bfd_link_hash_indirect
706 && dir->got.refcount <= 0)
707 {
708 edir->tls_type = eind->tls_type;
709 eind->tls_type = GOT_UNKNOWN;
710 }
711
712 if (ELIMINATE_COPY_RELOCS
713 && ind->root.type != bfd_link_hash_indirect
714 && dir->dynamic_adjusted)
715 {
716 /* If called to transfer flags for a weakdef during processing
717 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
718 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
719 dir->ref_dynamic |= ind->ref_dynamic;
720 dir->ref_regular |= ind->ref_regular;
721 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
722 dir->needs_plt |= ind->needs_plt;
723 dir->pointer_equality_needed |= ind->pointer_equality_needed;
724 }
725 else
726 _bfd_elf_link_hash_copy_indirect (info, dir, ind);
727 }
728
729 static bfd_boolean
730 elf64_x86_64_elf_object_p (bfd *abfd)
731 {
732 /* Set the right machine number for an x86-64 elf64 file. */
733 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
734 return TRUE;
735 }
736
737 typedef union
738 {
739 unsigned char c[2];
740 uint16_t i;
741 }
742 x86_64_opcode16;
743
744 typedef union
745 {
746 unsigned char c[4];
747 uint32_t i;
748 }
749 x86_64_opcode32;
750
751 /* Return TRUE if the TLS access code sequence support transition
752 from R_TYPE. */
753
754 static bfd_boolean
755 elf64_x86_64_check_tls_transition (bfd *abfd, asection *sec,
756 bfd_byte *contents,
757 Elf_Internal_Shdr *symtab_hdr,
758 struct elf_link_hash_entry **sym_hashes,
759 unsigned int r_type,
760 const Elf_Internal_Rela *rel,
761 const Elf_Internal_Rela *relend)
762 {
763 unsigned int val;
764 unsigned long r_symndx;
765 struct elf_link_hash_entry *h;
766 bfd_vma offset;
767
768 /* Get the section contents. */
769 if (contents == NULL)
770 {
771 if (elf_section_data (sec)->this_hdr.contents != NULL)
772 contents = elf_section_data (sec)->this_hdr.contents;
773 else
774 {
775 /* FIXME: How to better handle error condition? */
776 if (!bfd_malloc_and_get_section (abfd, sec, &contents))
777 return FALSE;
778
779 /* Cache the section contents for elf_link_input_bfd. */
780 elf_section_data (sec)->this_hdr.contents = contents;
781 }
782 }
783
784 offset = rel->r_offset;
785 switch (r_type)
786 {
787 case R_X86_64_TLSGD:
788 case R_X86_64_TLSLD:
789 if ((rel + 1) >= relend)
790 return FALSE;
791
792 if (r_type == R_X86_64_TLSGD)
793 {
794 /* Check transition from GD access model. Only
795 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
796 .word 0x6666; rex64; call __tls_get_addr
797 can transit to different access model. */
798
799 static x86_64_opcode32 leaq = { { 0x66, 0x48, 0x8d, 0x3d } },
800 call = { { 0x66, 0x66, 0x48, 0xe8 } };
801 if (offset < 4
802 || (offset + 12) > sec->size
803 || bfd_get_32 (abfd, contents + offset - 4) != leaq.i
804 || bfd_get_32 (abfd, contents + offset + 4) != call.i)
805 return FALSE;
806 }
807 else
808 {
809 /* Check transition from LD access model. Only
810 leaq foo@tlsld(%rip), %rdi;
811 call __tls_get_addr
812 can transit to different access model. */
813
814 static x86_64_opcode32 ld = { { 0x48, 0x8d, 0x3d, 0xe8 } };
815 x86_64_opcode32 op;
816
817 if (offset < 3 || (offset + 9) > sec->size)
818 return FALSE;
819
820 op.i = bfd_get_32 (abfd, contents + offset - 3);
821 op.c[3] = bfd_get_8 (abfd, contents + offset + 4);
822 if (op.i != ld.i)
823 return FALSE;
824 }
825
826 r_symndx = ELF64_R_SYM (rel[1].r_info);
827 if (r_symndx < symtab_hdr->sh_info)
828 return FALSE;
829
830 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
831 /* Use strncmp to check __tls_get_addr since __tls_get_addr
832 may be versioned. */
833 return (h != NULL
834 && h->root.root.string != NULL
835 && (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PC32
836 || ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32)
837 && (strncmp (h->root.root.string,
838 "__tls_get_addr", 14) == 0));
839
840 case R_X86_64_GOTTPOFF:
841 /* Check transition from IE access model:
842 movq foo@gottpoff(%rip), %reg
843 addq foo@gottpoff(%rip), %reg
844 */
845
846 if (offset < 3 || (offset + 4) > sec->size)
847 return FALSE;
848
849 val = bfd_get_8 (abfd, contents + offset - 3);
850 if (val != 0x48 && val != 0x4c)
851 return FALSE;
852
853 val = bfd_get_8 (abfd, contents + offset - 2);
854 if (val != 0x8b && val != 0x03)
855 return FALSE;
856
857 val = bfd_get_8 (abfd, contents + offset - 1);
858 return (val & 0xc7) == 5;
859
860 case R_X86_64_GOTPC32_TLSDESC:
861 /* Check transition from GDesc access model:
862 leaq x@tlsdesc(%rip), %rax
863
864 Make sure it's a leaq adding rip to a 32-bit offset
865 into any register, although it's probably almost always
866 going to be rax. */
867
868 if (offset < 3 || (offset + 4) > sec->size)
869 return FALSE;
870
871 val = bfd_get_8 (abfd, contents + offset - 3);
872 if ((val & 0xfb) != 0x48)
873 return FALSE;
874
875 if (bfd_get_8 (abfd, contents + offset - 2) != 0x8d)
876 return FALSE;
877
878 val = bfd_get_8 (abfd, contents + offset - 1);
879 return (val & 0xc7) == 0x05;
880
881 case R_X86_64_TLSDESC_CALL:
882 /* Check transition from GDesc access model:
883 call *x@tlsdesc(%rax)
884 */
885 if (offset + 2 <= sec->size)
886 {
887 /* Make sure that it's a call *x@tlsdesc(%rax). */
888 static x86_64_opcode16 call = { { 0xff, 0x10 } };
889 return bfd_get_16 (abfd, contents + offset) == call.i;
890 }
891
892 return FALSE;
893
894 default:
895 abort ();
896 }
897 }
898
899 /* Return TRUE if the TLS access transition is OK or no transition
900 will be performed. Update R_TYPE if there is a transition. */
901
902 static bfd_boolean
903 elf64_x86_64_tls_transition (struct bfd_link_info *info, bfd *abfd,
904 asection *sec, bfd_byte *contents,
905 Elf_Internal_Shdr *symtab_hdr,
906 struct elf_link_hash_entry **sym_hashes,
907 unsigned int *r_type, int tls_type,
908 const Elf_Internal_Rela *rel,
909 const Elf_Internal_Rela *relend,
910 struct elf_link_hash_entry *h)
911 {
912 unsigned int from_type = *r_type;
913 unsigned int to_type = from_type;
914 bfd_boolean check = TRUE;
915
916 switch (from_type)
917 {
918 case R_X86_64_TLSGD:
919 case R_X86_64_GOTPC32_TLSDESC:
920 case R_X86_64_TLSDESC_CALL:
921 case R_X86_64_GOTTPOFF:
922 if (!info->shared)
923 {
924 if (h == NULL)
925 to_type = R_X86_64_TPOFF32;
926 else
927 to_type = R_X86_64_GOTTPOFF;
928 }
929
930 /* When we are called from elf64_x86_64_relocate_section,
931 CONTENTS isn't NULL and there may be additional transitions
932 based on TLS_TYPE. */
933 if (contents != NULL)
934 {
935 unsigned int new_to_type = to_type;
936
937 if (!info->shared
938 && h != NULL
939 && h->dynindx == -1
940 && tls_type == GOT_TLS_IE)
941 new_to_type = R_X86_64_TPOFF32;
942
943 if (to_type == R_X86_64_TLSGD
944 || to_type == R_X86_64_GOTPC32_TLSDESC
945 || to_type == R_X86_64_TLSDESC_CALL)
946 {
947 if (tls_type == GOT_TLS_IE)
948 new_to_type = R_X86_64_GOTTPOFF;
949 }
950
951 /* We checked the transition before when we were called from
952 elf64_x86_64_check_relocs. We only want to check the new
953 transition which hasn't been checked before. */
954 check = new_to_type != to_type && from_type == to_type;
955 to_type = new_to_type;
956 }
957
958 break;
959
960 case R_X86_64_TLSLD:
961 if (!info->shared)
962 to_type = R_X86_64_TPOFF32;
963 break;
964
965 default:
966 return TRUE;
967 }
968
969 /* Return TRUE if there is no transition. */
970 if (from_type == to_type)
971 return TRUE;
972
973 /* Check if the transition can be performed. */
974 if (check
975 && ! elf64_x86_64_check_tls_transition (abfd, sec, contents,
976 symtab_hdr, sym_hashes,
977 from_type, rel, relend))
978 {
979 reloc_howto_type *from, *to;
980
981 from = elf64_x86_64_rtype_to_howto (abfd, from_type);
982 to = elf64_x86_64_rtype_to_howto (abfd, to_type);
983
984 (*_bfd_error_handler)
985 (_("%B: TLS transition from %s to %s against `%s' at 0x%lx "
986 "in section `%A' failed"),
987 abfd, sec, from->name, to->name,
988 h ? h->root.root.string : "a local symbol",
989 (unsigned long) rel->r_offset);
990 bfd_set_error (bfd_error_bad_value);
991 return FALSE;
992 }
993
994 *r_type = to_type;
995 return TRUE;
996 }
997
998 /* Look through the relocs for a section during the first phase, and
999 calculate needed space in the global offset table, procedure
1000 linkage table, and dynamic reloc sections. */
1001
1002 static bfd_boolean
1003 elf64_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
1004 asection *sec,
1005 const Elf_Internal_Rela *relocs)
1006 {
1007 struct elf64_x86_64_link_hash_table *htab;
1008 Elf_Internal_Shdr *symtab_hdr;
1009 struct elf_link_hash_entry **sym_hashes;
1010 const Elf_Internal_Rela *rel;
1011 const Elf_Internal_Rela *rel_end;
1012 asection *sreloc;
1013
1014 if (info->relocatable)
1015 return TRUE;
1016
1017 BFD_ASSERT (is_x86_64_elf (abfd));
1018
1019 htab = elf64_x86_64_hash_table (info);
1020 symtab_hdr = &elf_symtab_hdr (abfd);
1021 sym_hashes = elf_sym_hashes (abfd);
1022
1023 sreloc = NULL;
1024
1025 rel_end = relocs + sec->reloc_count;
1026 for (rel = relocs; rel < rel_end; rel++)
1027 {
1028 unsigned int r_type;
1029 unsigned long r_symndx;
1030 struct elf_link_hash_entry *h;
1031
1032 r_symndx = ELF64_R_SYM (rel->r_info);
1033 r_type = ELF64_R_TYPE (rel->r_info);
1034
1035 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
1036 {
1037 (*_bfd_error_handler) (_("%B: bad symbol index: %d"),
1038 abfd, r_symndx);
1039 return FALSE;
1040 }
1041
1042 if (r_symndx < symtab_hdr->sh_info)
1043 h = NULL;
1044 else
1045 {
1046 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1047 while (h->root.type == bfd_link_hash_indirect
1048 || h->root.type == bfd_link_hash_warning)
1049 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1050
1051 /* Create the ifunc sections for static executables. If we
1052 never see an indirect function symbol nor we are building
1053 a static executable, those sections will be empty and
1054 won't appear in output. */
1055 switch (r_type)
1056 {
1057 default:
1058 break;
1059
1060 case R_X86_64_32S:
1061 case R_X86_64_32:
1062 case R_X86_64_64:
1063 case R_X86_64_PC32:
1064 case R_X86_64_PC64:
1065 case R_X86_64_PLT32:
1066 case R_X86_64_GOTPCREL:
1067 case R_X86_64_GOTPCREL64:
1068 if (!info->shared && htab->iplt == NULL)
1069 {
1070 if (!_bfd_elf_create_static_ifunc_sections (abfd,
1071 info))
1072 return FALSE;
1073
1074 htab->iplt = bfd_get_section_by_name (abfd, ".iplt");
1075 htab->irelplt = bfd_get_section_by_name (abfd,
1076 ".rela.iplt");
1077 htab->igotplt = bfd_get_section_by_name (abfd,
1078 ".igot.plt");
1079 if (!htab->iplt
1080 || !htab->irelplt
1081 || !htab->igotplt)
1082 abort ();
1083 }
1084 break;
1085 }
1086
1087 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle
1088 it here if it is defined in a non-shared object. */
1089 if (h->type == STT_GNU_IFUNC
1090 && h->def_regular)
1091 {
1092 /* It is referenced by a non-shared object. */
1093 h->ref_regular = 1;
1094
1095 /* STT_GNU_IFUNC symbol must go through PLT. */
1096 h->plt.refcount += 1;
1097
1098 /* STT_GNU_IFUNC needs dynamic sections. */
1099 if (htab->elf.dynobj == NULL)
1100 htab->elf.dynobj = abfd;
1101
1102 switch (r_type)
1103 {
1104 default:
1105 (*_bfd_error_handler)
1106 (_("%B: relocation %s against STT_GNU_IFUNC "
1107 "symbol `%s' isn't handled by %s"), abfd,
1108 x86_64_elf_howto_table[r_type].name,
1109 h->root.root.string, __FUNCTION__);
1110 bfd_set_error (bfd_error_bad_value);
1111 return FALSE;
1112
1113 case R_X86_64_32S:
1114 case R_X86_64_32:
1115 case R_X86_64_64:
1116 case R_X86_64_PC32:
1117 case R_X86_64_PC64:
1118 h->non_got_ref = 1;
1119 if (r_type != R_X86_64_PC32
1120 && r_type != R_X86_64_PC64)
1121 h->pointer_equality_needed = 1;
1122 break;
1123
1124 case R_X86_64_PLT32:
1125 break;
1126
1127 case R_X86_64_GOTPCREL:
1128 case R_X86_64_GOTPCREL64:
1129 h->got.refcount += 1;
1130 if (htab->sgot == NULL
1131 && !elf64_x86_64_create_got_section (htab->elf.dynobj,
1132 info))
1133 return FALSE;
1134 break;
1135 }
1136
1137 continue;
1138 }
1139 }
1140
1141 if (! elf64_x86_64_tls_transition (info, abfd, sec, NULL,
1142 symtab_hdr, sym_hashes,
1143 &r_type, GOT_UNKNOWN,
1144 rel, rel_end, h))
1145 return FALSE;
1146
1147 switch (r_type)
1148 {
1149 case R_X86_64_TLSLD:
1150 htab->tls_ld_got.refcount += 1;
1151 goto create_got;
1152
1153 case R_X86_64_TPOFF32:
1154 if (info->shared)
1155 {
1156 (*_bfd_error_handler)
1157 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
1158 abfd,
1159 x86_64_elf_howto_table[r_type].name,
1160 (h) ? h->root.root.string : "a local symbol");
1161 bfd_set_error (bfd_error_bad_value);
1162 return FALSE;
1163 }
1164 break;
1165
1166 case R_X86_64_GOTTPOFF:
1167 if (info->shared)
1168 info->flags |= DF_STATIC_TLS;
1169 /* Fall through */
1170
1171 case R_X86_64_GOT32:
1172 case R_X86_64_GOTPCREL:
1173 case R_X86_64_TLSGD:
1174 case R_X86_64_GOT64:
1175 case R_X86_64_GOTPCREL64:
1176 case R_X86_64_GOTPLT64:
1177 case R_X86_64_GOTPC32_TLSDESC:
1178 case R_X86_64_TLSDESC_CALL:
1179 /* This symbol requires a global offset table entry. */
1180 {
1181 int tls_type, old_tls_type;
1182
1183 switch (r_type)
1184 {
1185 default: tls_type = GOT_NORMAL; break;
1186 case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
1187 case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
1188 case R_X86_64_GOTPC32_TLSDESC:
1189 case R_X86_64_TLSDESC_CALL:
1190 tls_type = GOT_TLS_GDESC; break;
1191 }
1192
1193 if (h != NULL)
1194 {
1195 if (r_type == R_X86_64_GOTPLT64)
1196 {
1197 /* This relocation indicates that we also need
1198 a PLT entry, as this is a function. We don't need
1199 a PLT entry for local symbols. */
1200 h->needs_plt = 1;
1201 h->plt.refcount += 1;
1202 }
1203 h->got.refcount += 1;
1204 old_tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1205 }
1206 else
1207 {
1208 bfd_signed_vma *local_got_refcounts;
1209
1210 /* This is a global offset table entry for a local symbol. */
1211 local_got_refcounts = elf_local_got_refcounts (abfd);
1212 if (local_got_refcounts == NULL)
1213 {
1214 bfd_size_type size;
1215
1216 size = symtab_hdr->sh_info;
1217 size *= sizeof (bfd_signed_vma)
1218 + sizeof (bfd_vma) + sizeof (char);
1219 local_got_refcounts = ((bfd_signed_vma *)
1220 bfd_zalloc (abfd, size));
1221 if (local_got_refcounts == NULL)
1222 return FALSE;
1223 elf_local_got_refcounts (abfd) = local_got_refcounts;
1224 elf64_x86_64_local_tlsdesc_gotent (abfd)
1225 = (bfd_vma *) (local_got_refcounts + symtab_hdr->sh_info);
1226 elf64_x86_64_local_got_tls_type (abfd)
1227 = (char *) (local_got_refcounts + 2 * symtab_hdr->sh_info);
1228 }
1229 local_got_refcounts[r_symndx] += 1;
1230 old_tls_type
1231 = elf64_x86_64_local_got_tls_type (abfd) [r_symndx];
1232 }
1233
1234 /* If a TLS symbol is accessed using IE at least once,
1235 there is no point to use dynamic model for it. */
1236 if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
1237 && (! GOT_TLS_GD_ANY_P (old_tls_type)
1238 || tls_type != GOT_TLS_IE))
1239 {
1240 if (old_tls_type == GOT_TLS_IE && GOT_TLS_GD_ANY_P (tls_type))
1241 tls_type = old_tls_type;
1242 else if (GOT_TLS_GD_ANY_P (old_tls_type)
1243 && GOT_TLS_GD_ANY_P (tls_type))
1244 tls_type |= old_tls_type;
1245 else
1246 {
1247 (*_bfd_error_handler)
1248 (_("%B: '%s' accessed both as normal and thread local symbol"),
1249 abfd, h ? h->root.root.string : "<local>");
1250 return FALSE;
1251 }
1252 }
1253
1254 if (old_tls_type != tls_type)
1255 {
1256 if (h != NULL)
1257 elf64_x86_64_hash_entry (h)->tls_type = tls_type;
1258 else
1259 elf64_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
1260 }
1261 }
1262 /* Fall through */
1263
1264 case R_X86_64_GOTOFF64:
1265 case R_X86_64_GOTPC32:
1266 case R_X86_64_GOTPC64:
1267 create_got:
1268 if (htab->sgot == NULL)
1269 {
1270 if (htab->elf.dynobj == NULL)
1271 htab->elf.dynobj = abfd;
1272 if (!elf64_x86_64_create_got_section (htab->elf.dynobj,
1273 info))
1274 return FALSE;
1275 }
1276 break;
1277
1278 case R_X86_64_PLT32:
1279 /* This symbol requires a procedure linkage table entry. We
1280 actually build the entry in adjust_dynamic_symbol,
1281 because this might be a case of linking PIC code which is
1282 never referenced by a dynamic object, in which case we
1283 don't need to generate a procedure linkage table entry
1284 after all. */
1285
1286 /* If this is a local symbol, we resolve it directly without
1287 creating a procedure linkage table entry. */
1288 if (h == NULL)
1289 continue;
1290
1291 h->needs_plt = 1;
1292 h->plt.refcount += 1;
1293 break;
1294
1295 case R_X86_64_PLTOFF64:
1296 /* This tries to form the 'address' of a function relative
1297 to GOT. For global symbols we need a PLT entry. */
1298 if (h != NULL)
1299 {
1300 h->needs_plt = 1;
1301 h->plt.refcount += 1;
1302 }
1303 goto create_got;
1304
1305 case R_X86_64_8:
1306 case R_X86_64_16:
1307 case R_X86_64_32:
1308 case R_X86_64_32S:
1309 /* Let's help debug shared library creation. These relocs
1310 cannot be used in shared libs. Don't error out for
1311 sections we don't care about, such as debug sections or
1312 non-constant sections. */
1313 if (info->shared
1314 && (sec->flags & SEC_ALLOC) != 0
1315 && (sec->flags & SEC_READONLY) != 0)
1316 {
1317 (*_bfd_error_handler)
1318 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
1319 abfd,
1320 x86_64_elf_howto_table[r_type].name,
1321 (h) ? h->root.root.string : "a local symbol");
1322 bfd_set_error (bfd_error_bad_value);
1323 return FALSE;
1324 }
1325 /* Fall through. */
1326
1327 case R_X86_64_PC8:
1328 case R_X86_64_PC16:
1329 case R_X86_64_PC32:
1330 case R_X86_64_PC64:
1331 case R_X86_64_64:
1332 if (h != NULL && !info->shared)
1333 {
1334 /* If this reloc is in a read-only section, we might
1335 need a copy reloc. We can't check reliably at this
1336 stage whether the section is read-only, as input
1337 sections have not yet been mapped to output sections.
1338 Tentatively set the flag for now, and correct in
1339 adjust_dynamic_symbol. */
1340 h->non_got_ref = 1;
1341
1342 /* We may need a .plt entry if the function this reloc
1343 refers to is in a shared lib. */
1344 h->plt.refcount += 1;
1345 if (r_type != R_X86_64_PC32 && r_type != R_X86_64_PC64)
1346 h->pointer_equality_needed = 1;
1347 }
1348
1349 /* If we are creating a shared library, and this is a reloc
1350 against a global symbol, or a non PC relative reloc
1351 against a local symbol, then we need to copy the reloc
1352 into the shared library. However, if we are linking with
1353 -Bsymbolic, we do not need to copy a reloc against a
1354 global symbol which is defined in an object we are
1355 including in the link (i.e., DEF_REGULAR is set). At
1356 this point we have not seen all the input files, so it is
1357 possible that DEF_REGULAR is not set now but will be set
1358 later (it is never cleared). In case of a weak definition,
1359 DEF_REGULAR may be cleared later by a strong definition in
1360 a shared library. We account for that possibility below by
1361 storing information in the relocs_copied field of the hash
1362 table entry. A similar situation occurs when creating
1363 shared libraries and symbol visibility changes render the
1364 symbol local.
1365
1366 If on the other hand, we are creating an executable, we
1367 may need to keep relocations for symbols satisfied by a
1368 dynamic library if we manage to avoid copy relocs for the
1369 symbol. */
1370 if ((info->shared
1371 && (sec->flags & SEC_ALLOC) != 0
1372 && (! IS_X86_64_PCREL_TYPE (r_type)
1373 || (h != NULL
1374 && (! SYMBOLIC_BIND (info, h)
1375 || h->root.type == bfd_link_hash_defweak
1376 || !h->def_regular))))
1377 || (ELIMINATE_COPY_RELOCS
1378 && !info->shared
1379 && (sec->flags & SEC_ALLOC) != 0
1380 && h != NULL
1381 && (h->root.type == bfd_link_hash_defweak
1382 || !h->def_regular)))
1383 {
1384 struct elf64_x86_64_dyn_relocs *p;
1385 struct elf64_x86_64_dyn_relocs **head;
1386
1387 /* We must copy these reloc types into the output file.
1388 Create a reloc section in dynobj and make room for
1389 this reloc. */
1390 if (sreloc == NULL)
1391 {
1392 if (htab->elf.dynobj == NULL)
1393 htab->elf.dynobj = abfd;
1394
1395 sreloc = _bfd_elf_make_dynamic_reloc_section
1396 (sec, htab->elf.dynobj, 3, abfd, /*rela?*/ TRUE);
1397
1398 if (sreloc == NULL)
1399 return FALSE;
1400 }
1401
1402 /* If this is a global symbol, we count the number of
1403 relocations we need for this symbol. */
1404 if (h != NULL)
1405 {
1406 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs;
1407 }
1408 else
1409 {
1410 void **vpp;
1411 /* Track dynamic relocs needed for local syms too.
1412 We really need local syms available to do this
1413 easily. Oh well. */
1414
1415 asection *s;
1416 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
1417 sec, r_symndx);
1418 if (s == NULL)
1419 return FALSE;
1420
1421 /* Beware of type punned pointers vs strict aliasing
1422 rules. */
1423 vpp = &(elf_section_data (s)->local_dynrel);
1424 head = (struct elf64_x86_64_dyn_relocs **)vpp;
1425 }
1426
1427 p = *head;
1428 if (p == NULL || p->sec != sec)
1429 {
1430 bfd_size_type amt = sizeof *p;
1431
1432 p = ((struct elf64_x86_64_dyn_relocs *)
1433 bfd_alloc (htab->elf.dynobj, amt));
1434 if (p == NULL)
1435 return FALSE;
1436 p->next = *head;
1437 *head = p;
1438 p->sec = sec;
1439 p->count = 0;
1440 p->pc_count = 0;
1441 }
1442
1443 p->count += 1;
1444 if (IS_X86_64_PCREL_TYPE (r_type))
1445 p->pc_count += 1;
1446 }
1447 break;
1448
1449 /* This relocation describes the C++ object vtable hierarchy.
1450 Reconstruct it for later use during GC. */
1451 case R_X86_64_GNU_VTINHERIT:
1452 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
1453 return FALSE;
1454 break;
1455
1456 /* This relocation describes which C++ vtable entries are actually
1457 used. Record for later use during GC. */
1458 case R_X86_64_GNU_VTENTRY:
1459 BFD_ASSERT (h != NULL);
1460 if (h != NULL
1461 && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
1462 return FALSE;
1463 break;
1464
1465 default:
1466 break;
1467 }
1468 }
1469
1470 return TRUE;
1471 }
1472
1473 /* Return the section that should be marked against GC for a given
1474 relocation. */
1475
1476 static asection *
1477 elf64_x86_64_gc_mark_hook (asection *sec,
1478 struct bfd_link_info *info,
1479 Elf_Internal_Rela *rel,
1480 struct elf_link_hash_entry *h,
1481 Elf_Internal_Sym *sym)
1482 {
1483 if (h != NULL)
1484 switch (ELF64_R_TYPE (rel->r_info))
1485 {
1486 case R_X86_64_GNU_VTINHERIT:
1487 case R_X86_64_GNU_VTENTRY:
1488 return NULL;
1489 }
1490
1491 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
1492 }
1493
1494 /* Update the got entry reference counts for the section being removed. */
1495
1496 static bfd_boolean
1497 elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
1498 asection *sec,
1499 const Elf_Internal_Rela *relocs)
1500 {
1501 Elf_Internal_Shdr *symtab_hdr;
1502 struct elf_link_hash_entry **sym_hashes;
1503 bfd_signed_vma *local_got_refcounts;
1504 const Elf_Internal_Rela *rel, *relend;
1505
1506 if (info->relocatable)
1507 return TRUE;
1508
1509 elf_section_data (sec)->local_dynrel = NULL;
1510
1511 symtab_hdr = &elf_symtab_hdr (abfd);
1512 sym_hashes = elf_sym_hashes (abfd);
1513 local_got_refcounts = elf_local_got_refcounts (abfd);
1514
1515 relend = relocs + sec->reloc_count;
1516 for (rel = relocs; rel < relend; rel++)
1517 {
1518 unsigned long r_symndx;
1519 unsigned int r_type;
1520 struct elf_link_hash_entry *h = NULL;
1521
1522 r_symndx = ELF64_R_SYM (rel->r_info);
1523 if (r_symndx >= symtab_hdr->sh_info)
1524 {
1525 struct elf64_x86_64_link_hash_entry *eh;
1526 struct elf64_x86_64_dyn_relocs **pp;
1527 struct elf64_x86_64_dyn_relocs *p;
1528
1529 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1530 while (h->root.type == bfd_link_hash_indirect
1531 || h->root.type == bfd_link_hash_warning)
1532 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1533 eh = (struct elf64_x86_64_link_hash_entry *) h;
1534
1535 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1536 if (p->sec == sec)
1537 {
1538 /* Everything must go for SEC. */
1539 *pp = p->next;
1540 break;
1541 }
1542 }
1543
1544 r_type = ELF64_R_TYPE (rel->r_info);
1545 if (! elf64_x86_64_tls_transition (info, abfd, sec, NULL,
1546 symtab_hdr, sym_hashes,
1547 &r_type, GOT_UNKNOWN,
1548 rel, relend, h))
1549 return FALSE;
1550
1551 switch (r_type)
1552 {
1553 case R_X86_64_TLSLD:
1554 if (elf64_x86_64_hash_table (info)->tls_ld_got.refcount > 0)
1555 elf64_x86_64_hash_table (info)->tls_ld_got.refcount -= 1;
1556 break;
1557
1558 case R_X86_64_TLSGD:
1559 case R_X86_64_GOTPC32_TLSDESC:
1560 case R_X86_64_TLSDESC_CALL:
1561 case R_X86_64_GOTTPOFF:
1562 case R_X86_64_GOT32:
1563 case R_X86_64_GOTPCREL:
1564 case R_X86_64_GOT64:
1565 case R_X86_64_GOTPCREL64:
1566 case R_X86_64_GOTPLT64:
1567 if (h != NULL)
1568 {
1569 if (r_type == R_X86_64_GOTPLT64 && h->plt.refcount > 0)
1570 h->plt.refcount -= 1;
1571 if (h->got.refcount > 0)
1572 h->got.refcount -= 1;
1573 }
1574 else if (local_got_refcounts != NULL)
1575 {
1576 if (local_got_refcounts[r_symndx] > 0)
1577 local_got_refcounts[r_symndx] -= 1;
1578 }
1579 break;
1580
1581 case R_X86_64_8:
1582 case R_X86_64_16:
1583 case R_X86_64_32:
1584 case R_X86_64_64:
1585 case R_X86_64_32S:
1586 case R_X86_64_PC8:
1587 case R_X86_64_PC16:
1588 case R_X86_64_PC32:
1589 case R_X86_64_PC64:
1590 if (info->shared)
1591 break;
1592 /* Fall thru */
1593
1594 case R_X86_64_PLT32:
1595 case R_X86_64_PLTOFF64:
1596 if (h != NULL)
1597 {
1598 if (h->plt.refcount > 0)
1599 h->plt.refcount -= 1;
1600 }
1601 break;
1602
1603 default:
1604 break;
1605 }
1606 }
1607
1608 return TRUE;
1609 }
1610
1611 /* Adjust a symbol defined by a dynamic object and referenced by a
1612 regular object. The current definition is in some section of the
1613 dynamic object, but we're not including those sections. We have to
1614 change the definition to something the rest of the link can
1615 understand. */
1616
1617 static bfd_boolean
1618 elf64_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
1619 struct elf_link_hash_entry *h)
1620 {
1621 struct elf64_x86_64_link_hash_table *htab;
1622 asection *s;
1623
1624 /* STT_GNU_IFUNC symbol must go through PLT. */
1625 if (h->type == STT_GNU_IFUNC)
1626 {
1627 if (h->plt.refcount <= 0)
1628 {
1629 h->plt.offset = (bfd_vma) -1;
1630 h->needs_plt = 0;
1631 }
1632 return TRUE;
1633 }
1634
1635 /* If this is a function, put it in the procedure linkage table. We
1636 will fill in the contents of the procedure linkage table later,
1637 when we know the address of the .got section. */
1638 if (h->type == STT_FUNC
1639 || h->needs_plt)
1640 {
1641 if (h->plt.refcount <= 0
1642 || SYMBOL_CALLS_LOCAL (info, h)
1643 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1644 && h->root.type == bfd_link_hash_undefweak))
1645 {
1646 /* This case can occur if we saw a PLT32 reloc in an input
1647 file, but the symbol was never referred to by a dynamic
1648 object, or if all references were garbage collected. In
1649 such a case, we don't actually need to build a procedure
1650 linkage table, and we can just do a PC32 reloc instead. */
1651 h->plt.offset = (bfd_vma) -1;
1652 h->needs_plt = 0;
1653 }
1654
1655 return TRUE;
1656 }
1657 else
1658 /* It's possible that we incorrectly decided a .plt reloc was
1659 needed for an R_X86_64_PC32 reloc to a non-function sym in
1660 check_relocs. We can't decide accurately between function and
1661 non-function syms in check-relocs; Objects loaded later in
1662 the link may change h->type. So fix it now. */
1663 h->plt.offset = (bfd_vma) -1;
1664
1665 /* If this is a weak symbol, and there is a real definition, the
1666 processor independent code will have arranged for us to see the
1667 real definition first, and we can just use the same value. */
1668 if (h->u.weakdef != NULL)
1669 {
1670 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1671 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1672 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1673 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1674 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1675 h->non_got_ref = h->u.weakdef->non_got_ref;
1676 return TRUE;
1677 }
1678
1679 /* This is a reference to a symbol defined by a dynamic object which
1680 is not a function. */
1681
1682 /* If we are creating a shared library, we must presume that the
1683 only references to the symbol are via the global offset table.
1684 For such cases we need not do anything here; the relocations will
1685 be handled correctly by relocate_section. */
1686 if (info->shared)
1687 return TRUE;
1688
1689 /* If there are no references to this symbol that do not use the
1690 GOT, we don't need to generate a copy reloc. */
1691 if (!h->non_got_ref)
1692 return TRUE;
1693
1694 /* If -z nocopyreloc was given, we won't generate them either. */
1695 if (info->nocopyreloc)
1696 {
1697 h->non_got_ref = 0;
1698 return TRUE;
1699 }
1700
1701 if (ELIMINATE_COPY_RELOCS)
1702 {
1703 struct elf64_x86_64_link_hash_entry * eh;
1704 struct elf64_x86_64_dyn_relocs *p;
1705
1706 eh = (struct elf64_x86_64_link_hash_entry *) h;
1707 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1708 {
1709 s = p->sec->output_section;
1710 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1711 break;
1712 }
1713
1714 /* If we didn't find any dynamic relocs in read-only sections, then
1715 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1716 if (p == NULL)
1717 {
1718 h->non_got_ref = 0;
1719 return TRUE;
1720 }
1721 }
1722
1723 if (h->size == 0)
1724 {
1725 (*_bfd_error_handler) (_("dynamic variable `%s' is zero size"),
1726 h->root.root.string);
1727 return TRUE;
1728 }
1729
1730 /* We must allocate the symbol in our .dynbss section, which will
1731 become part of the .bss section of the executable. There will be
1732 an entry for this symbol in the .dynsym section. The dynamic
1733 object will contain position independent code, so all references
1734 from the dynamic object to this symbol will go through the global
1735 offset table. The dynamic linker will use the .dynsym entry to
1736 determine the address it must put in the global offset table, so
1737 both the dynamic object and the regular object will refer to the
1738 same memory location for the variable. */
1739
1740 htab = elf64_x86_64_hash_table (info);
1741
1742 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
1743 to copy the initial value out of the dynamic object and into the
1744 runtime process image. */
1745 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1746 {
1747 htab->srelbss->size += sizeof (Elf64_External_Rela);
1748 h->needs_copy = 1;
1749 }
1750
1751 s = htab->sdynbss;
1752
1753 return _bfd_elf_adjust_dynamic_copy (h, s);
1754 }
1755
1756 /* Allocate space in .plt, .got and associated reloc sections for
1757 dynamic relocs. */
1758
1759 static bfd_boolean
1760 elf64_x86_64_allocate_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1761 {
1762 struct bfd_link_info *info;
1763 struct elf64_x86_64_link_hash_table *htab;
1764 struct elf64_x86_64_link_hash_entry *eh;
1765 struct elf64_x86_64_dyn_relocs *p;
1766
1767 if (h->root.type == bfd_link_hash_indirect)
1768 return TRUE;
1769
1770 if (h->root.type == bfd_link_hash_warning)
1771 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1772 eh = (struct elf64_x86_64_link_hash_entry *) h;
1773
1774 info = (struct bfd_link_info *) inf;
1775 htab = elf64_x86_64_hash_table (info);
1776
1777 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle it
1778 here if it is defined and referenced in a non-shared object. */
1779 if (h->type == STT_GNU_IFUNC
1780 && h->def_regular)
1781 {
1782 asection *plt, *gotplt, *relplt;
1783
1784 /* Return and discard space for dynamic relocations against it if
1785 it is never referenced in a non-shared object. */
1786 if (!h->ref_regular)
1787 {
1788 if (h->plt.refcount > 0
1789 || h->got.refcount > 0)
1790 abort ();
1791 h->got.offset = (bfd_vma) -1;
1792 eh->dyn_relocs = NULL;
1793 return TRUE;
1794 }
1795
1796 /* When building a static executable, use .iplt, .igot.plt and
1797 .rela.iplt sections for STT_GNU_IFUNC symbols. */
1798 if (htab->splt != 0)
1799 {
1800 plt = htab->splt;
1801 gotplt = htab->sgotplt;
1802 relplt = htab->srelplt;
1803
1804 /* If this is the first .plt entry, make room for the special
1805 first entry. */
1806 if (plt->size == 0)
1807 plt->size += PLT_ENTRY_SIZE;
1808 }
1809 else
1810 {
1811 plt = htab->iplt;
1812 gotplt = htab->igotplt;
1813 relplt = htab->irelplt;
1814 }
1815
1816 /* Don't update value of STT_GNU_IFUNC symbol to PLT. We need
1817 the original value for R_X86_64_IRELATIVE. */
1818 h->plt.offset = plt->size;
1819
1820 /* Make room for this entry in the .plt/.iplt section. */
1821 plt->size += PLT_ENTRY_SIZE;
1822
1823 /* We also need to make an entry in the .got.plt/.got.iplt
1824 section, which will be placed in the .got section by the
1825 linker script. */
1826 gotplt->size += GOT_ENTRY_SIZE;
1827
1828 /* We also need to make an entry in the .rela.plt/.rela.iplt
1829 section. */
1830 relplt->size += sizeof (Elf64_External_Rela);
1831 relplt->reloc_count++;
1832
1833 /* No need for dynamic relocation for local STT_GNU_IFUNC symbol.
1834 Discard space for relocations against it. */
1835 if (h->dynindx == -1 || h->forced_local)
1836 eh->dyn_relocs = NULL;
1837
1838 /* STT_GNU_IFUNC symbol uses .got.plt, not .got. But for
1839 shared library, we must go through GOT and we can't
1840 use R_X86_64_IRELATIVE unless it is forced local. */
1841 if (info->executable
1842 || info->symbolic
1843 || h->forced_local)
1844 {
1845 if (h->pointer_equality_needed
1846 && htab->sgot != NULL)
1847 {
1848 /* We can't use .got.plt, which contains the real
1849 function addres, since we need pointer equality.
1850 We will load the GOT entry with the PLT entry
1851 in elf64_x86_64_finish_dynamic_symbol and don't
1852 need GOT relocation. */
1853 h->got.offset = htab->sgot->size;
1854 htab->sgot->size += GOT_ENTRY_SIZE;
1855 eh->tlsdesc_got = (bfd_vma) -1;
1856 goto skip_relgot;
1857 }
1858 else
1859 h->got.refcount = 0;
1860 }
1861 }
1862 else if (htab->elf.dynamic_sections_created
1863 && h->plt.refcount > 0)
1864 {
1865 /* Make sure this symbol is output as a dynamic symbol.
1866 Undefined weak syms won't yet be marked as dynamic. */
1867 if (h->dynindx == -1
1868 && !h->forced_local)
1869 {
1870 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1871 return FALSE;
1872 }
1873
1874 if (info->shared
1875 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
1876 {
1877 asection *s = htab->splt;
1878
1879 /* If this is the first .plt entry, make room for the special
1880 first entry. */
1881 if (s->size == 0)
1882 s->size += PLT_ENTRY_SIZE;
1883
1884 h->plt.offset = s->size;
1885
1886 /* If this symbol is not defined in a regular file, and we are
1887 not generating a shared library, then set the symbol to this
1888 location in the .plt. This is required to make function
1889 pointers compare as equal between the normal executable and
1890 the shared library. */
1891 if (! info->shared
1892 && !h->def_regular)
1893 {
1894 h->root.u.def.section = s;
1895 h->root.u.def.value = h->plt.offset;
1896 }
1897
1898 /* Make room for this entry. */
1899 s->size += PLT_ENTRY_SIZE;
1900
1901 /* We also need to make an entry in the .got.plt section, which
1902 will be placed in the .got section by the linker script. */
1903 htab->sgotplt->size += GOT_ENTRY_SIZE;
1904
1905 /* We also need to make an entry in the .rela.plt section. */
1906 htab->srelplt->size += sizeof (Elf64_External_Rela);
1907 htab->srelplt->reloc_count++;
1908 }
1909 else
1910 {
1911 h->plt.offset = (bfd_vma) -1;
1912 h->needs_plt = 0;
1913 }
1914 }
1915 else
1916 {
1917 h->plt.offset = (bfd_vma) -1;
1918 h->needs_plt = 0;
1919 }
1920
1921 eh->tlsdesc_got = (bfd_vma) -1;
1922
1923 /* If R_X86_64_GOTTPOFF symbol is now local to the binary,
1924 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
1925 if (h->got.refcount > 0
1926 && !info->shared
1927 && h->dynindx == -1
1928 && elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
1929 {
1930 h->got.offset = (bfd_vma) -1;
1931 }
1932 else if (h->got.refcount > 0)
1933 {
1934 asection *s;
1935 bfd_boolean dyn;
1936 int tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1937
1938 /* Make sure this symbol is output as a dynamic symbol.
1939 Undefined weak syms won't yet be marked as dynamic. */
1940 if (h->dynindx == -1
1941 && !h->forced_local)
1942 {
1943 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1944 return FALSE;
1945 }
1946
1947 if (GOT_TLS_GDESC_P (tls_type))
1948 {
1949 eh->tlsdesc_got = htab->sgotplt->size
1950 - elf64_x86_64_compute_jump_table_size (htab);
1951 htab->sgotplt->size += 2 * GOT_ENTRY_SIZE;
1952 h->got.offset = (bfd_vma) -2;
1953 }
1954 if (! GOT_TLS_GDESC_P (tls_type)
1955 || GOT_TLS_GD_P (tls_type))
1956 {
1957 s = htab->sgot;
1958 h->got.offset = s->size;
1959 s->size += GOT_ENTRY_SIZE;
1960 if (GOT_TLS_GD_P (tls_type))
1961 s->size += GOT_ENTRY_SIZE;
1962 }
1963 dyn = htab->elf.dynamic_sections_created;
1964 /* R_X86_64_TLSGD needs one dynamic relocation if local symbol
1965 and two if global.
1966 R_X86_64_GOTTPOFF needs one dynamic relocation. */
1967 if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1)
1968 || tls_type == GOT_TLS_IE)
1969 htab->srelgot->size += sizeof (Elf64_External_Rela);
1970 else if (GOT_TLS_GD_P (tls_type))
1971 htab->srelgot->size += 2 * sizeof (Elf64_External_Rela);
1972 else if (! GOT_TLS_GDESC_P (tls_type)
1973 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1974 || h->root.type != bfd_link_hash_undefweak)
1975 && (info->shared
1976 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
1977 htab->srelgot->size += sizeof (Elf64_External_Rela);
1978 if (GOT_TLS_GDESC_P (tls_type))
1979 {
1980 htab->srelplt->size += sizeof (Elf64_External_Rela);
1981 htab->tlsdesc_plt = (bfd_vma) -1;
1982 }
1983 }
1984 else
1985 h->got.offset = (bfd_vma) -1;
1986
1987 skip_relgot:
1988 if (eh->dyn_relocs == NULL)
1989 return TRUE;
1990
1991 /* In the shared -Bsymbolic case, discard space allocated for
1992 dynamic pc-relative relocs against symbols which turn out to be
1993 defined in regular objects. For the normal shared case, discard
1994 space for pc-relative relocs that have become local due to symbol
1995 visibility changes. */
1996
1997 if (info->shared)
1998 {
1999 /* Relocs that use pc_count are those that appear on a call
2000 insn, or certain REL relocs that can generated via assembly.
2001 We want calls to protected symbols to resolve directly to the
2002 function rather than going via the plt. If people want
2003 function pointer comparisons to work as expected then they
2004 should avoid writing weird assembly. */
2005 if (SYMBOL_CALLS_LOCAL (info, h))
2006 {
2007 struct elf64_x86_64_dyn_relocs **pp;
2008
2009 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
2010 {
2011 p->count -= p->pc_count;
2012 p->pc_count = 0;
2013 if (p->count == 0)
2014 *pp = p->next;
2015 else
2016 pp = &p->next;
2017 }
2018 }
2019
2020 /* Also discard relocs on undefined weak syms with non-default
2021 visibility. */
2022 if (eh->dyn_relocs != NULL
2023 && h->root.type == bfd_link_hash_undefweak)
2024 {
2025 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2026 eh->dyn_relocs = NULL;
2027
2028 /* Make sure undefined weak symbols are output as a dynamic
2029 symbol in PIEs. */
2030 else if (h->dynindx == -1
2031 && ! h->forced_local
2032 && ! bfd_elf_link_record_dynamic_symbol (info, h))
2033 return FALSE;
2034 }
2035
2036 }
2037 else if (ELIMINATE_COPY_RELOCS)
2038 {
2039 /* For the non-shared case, discard space for relocs against
2040 symbols which turn out to need copy relocs or are not
2041 dynamic. */
2042
2043 if (!h->non_got_ref
2044 && ((h->def_dynamic
2045 && !h->def_regular)
2046 || (htab->elf.dynamic_sections_created
2047 && (h->root.type == bfd_link_hash_undefweak
2048 || h->root.type == bfd_link_hash_undefined))))
2049 {
2050 /* Make sure this symbol is output as a dynamic symbol.
2051 Undefined weak syms won't yet be marked as dynamic. */
2052 if (h->dynindx == -1
2053 && ! h->forced_local
2054 && ! bfd_elf_link_record_dynamic_symbol (info, h))
2055 return FALSE;
2056
2057 /* If that succeeded, we know we'll be keeping all the
2058 relocs. */
2059 if (h->dynindx != -1)
2060 goto keep;
2061 }
2062
2063 eh->dyn_relocs = NULL;
2064
2065 keep: ;
2066 }
2067
2068 /* Finally, allocate space. */
2069 for (p = eh->dyn_relocs; p != NULL; p = p->next)
2070 {
2071 asection * sreloc;
2072
2073 sreloc = elf_section_data (p->sec)->sreloc;
2074
2075 BFD_ASSERT (sreloc != NULL);
2076
2077 sreloc->size += p->count * sizeof (Elf64_External_Rela);
2078 }
2079
2080 return TRUE;
2081 }
2082
2083 /* Find any dynamic relocs that apply to read-only sections. */
2084
2085 static bfd_boolean
2086 elf64_x86_64_readonly_dynrelocs (struct elf_link_hash_entry *h, void * inf)
2087 {
2088 struct elf64_x86_64_link_hash_entry *eh;
2089 struct elf64_x86_64_dyn_relocs *p;
2090
2091 if (h->root.type == bfd_link_hash_warning)
2092 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2093
2094 eh = (struct elf64_x86_64_link_hash_entry *) h;
2095 for (p = eh->dyn_relocs; p != NULL; p = p->next)
2096 {
2097 asection *s = p->sec->output_section;
2098
2099 if (s != NULL && (s->flags & SEC_READONLY) != 0)
2100 {
2101 struct bfd_link_info *info = (struct bfd_link_info *) inf;
2102
2103 info->flags |= DF_TEXTREL;
2104
2105 /* Not an error, just cut short the traversal. */
2106 return FALSE;
2107 }
2108 }
2109 return TRUE;
2110 }
2111
2112 /* Set the sizes of the dynamic sections. */
2113
2114 static bfd_boolean
2115 elf64_x86_64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
2116 struct bfd_link_info *info)
2117 {
2118 struct elf64_x86_64_link_hash_table *htab;
2119 bfd *dynobj;
2120 asection *s;
2121 bfd_boolean relocs;
2122 bfd *ibfd;
2123
2124 htab = elf64_x86_64_hash_table (info);
2125 dynobj = htab->elf.dynobj;
2126 if (dynobj == NULL)
2127 abort ();
2128
2129 if (htab->elf.dynamic_sections_created)
2130 {
2131 /* Set the contents of the .interp section to the interpreter. */
2132 if (info->executable)
2133 {
2134 s = bfd_get_section_by_name (dynobj, ".interp");
2135 if (s == NULL)
2136 abort ();
2137 s->size = sizeof ELF_DYNAMIC_INTERPRETER;
2138 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
2139 }
2140 }
2141
2142 /* Set up .got offsets for local syms, and space for local dynamic
2143 relocs. */
2144 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
2145 {
2146 bfd_signed_vma *local_got;
2147 bfd_signed_vma *end_local_got;
2148 char *local_tls_type;
2149 bfd_vma *local_tlsdesc_gotent;
2150 bfd_size_type locsymcount;
2151 Elf_Internal_Shdr *symtab_hdr;
2152 asection *srel;
2153
2154 if (! is_x86_64_elf (ibfd))
2155 continue;
2156
2157 for (s = ibfd->sections; s != NULL; s = s->next)
2158 {
2159 struct elf64_x86_64_dyn_relocs *p;
2160
2161 for (p = (struct elf64_x86_64_dyn_relocs *)
2162 (elf_section_data (s)->local_dynrel);
2163 p != NULL;
2164 p = p->next)
2165 {
2166 if (!bfd_is_abs_section (p->sec)
2167 && bfd_is_abs_section (p->sec->output_section))
2168 {
2169 /* Input section has been discarded, either because
2170 it is a copy of a linkonce section or due to
2171 linker script /DISCARD/, so we'll be discarding
2172 the relocs too. */
2173 }
2174 else if (p->count != 0)
2175 {
2176 srel = elf_section_data (p->sec)->sreloc;
2177 srel->size += p->count * sizeof (Elf64_External_Rela);
2178 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
2179 info->flags |= DF_TEXTREL;
2180 }
2181 }
2182 }
2183
2184 local_got = elf_local_got_refcounts (ibfd);
2185 if (!local_got)
2186 continue;
2187
2188 symtab_hdr = &elf_symtab_hdr (ibfd);
2189 locsymcount = symtab_hdr->sh_info;
2190 end_local_got = local_got + locsymcount;
2191 local_tls_type = elf64_x86_64_local_got_tls_type (ibfd);
2192 local_tlsdesc_gotent = elf64_x86_64_local_tlsdesc_gotent (ibfd);
2193 s = htab->sgot;
2194 srel = htab->srelgot;
2195 for (; local_got < end_local_got;
2196 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent)
2197 {
2198 *local_tlsdesc_gotent = (bfd_vma) -1;
2199 if (*local_got > 0)
2200 {
2201 if (GOT_TLS_GDESC_P (*local_tls_type))
2202 {
2203 *local_tlsdesc_gotent = htab->sgotplt->size
2204 - elf64_x86_64_compute_jump_table_size (htab);
2205 htab->sgotplt->size += 2 * GOT_ENTRY_SIZE;
2206 *local_got = (bfd_vma) -2;
2207 }
2208 if (! GOT_TLS_GDESC_P (*local_tls_type)
2209 || GOT_TLS_GD_P (*local_tls_type))
2210 {
2211 *local_got = s->size;
2212 s->size += GOT_ENTRY_SIZE;
2213 if (GOT_TLS_GD_P (*local_tls_type))
2214 s->size += GOT_ENTRY_SIZE;
2215 }
2216 if (info->shared
2217 || GOT_TLS_GD_ANY_P (*local_tls_type)
2218 || *local_tls_type == GOT_TLS_IE)
2219 {
2220 if (GOT_TLS_GDESC_P (*local_tls_type))
2221 {
2222 htab->srelplt->size += sizeof (Elf64_External_Rela);
2223 htab->tlsdesc_plt = (bfd_vma) -1;
2224 }
2225 if (! GOT_TLS_GDESC_P (*local_tls_type)
2226 || GOT_TLS_GD_P (*local_tls_type))
2227 srel->size += sizeof (Elf64_External_Rela);
2228 }
2229 }
2230 else
2231 *local_got = (bfd_vma) -1;
2232 }
2233 }
2234
2235 if (htab->tls_ld_got.refcount > 0)
2236 {
2237 /* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD
2238 relocs. */
2239 htab->tls_ld_got.offset = htab->sgot->size;
2240 htab->sgot->size += 2 * GOT_ENTRY_SIZE;
2241 htab->srelgot->size += sizeof (Elf64_External_Rela);
2242 }
2243 else
2244 htab->tls_ld_got.offset = -1;
2245
2246 /* Allocate global sym .plt and .got entries, and space for global
2247 sym dynamic relocs. */
2248 elf_link_hash_traverse (&htab->elf, elf64_x86_64_allocate_dynrelocs,
2249 info);
2250
2251 /* For every jump slot reserved in the sgotplt, reloc_count is
2252 incremented. However, when we reserve space for TLS descriptors,
2253 it's not incremented, so in order to compute the space reserved
2254 for them, it suffices to multiply the reloc count by the jump
2255 slot size. */
2256 if (htab->srelplt)
2257 htab->sgotplt_jump_table_size
2258 = elf64_x86_64_compute_jump_table_size (htab);
2259
2260 if (htab->tlsdesc_plt)
2261 {
2262 /* If we're not using lazy TLS relocations, don't generate the
2263 PLT and GOT entries they require. */
2264 if ((info->flags & DF_BIND_NOW))
2265 htab->tlsdesc_plt = 0;
2266 else
2267 {
2268 htab->tlsdesc_got = htab->sgot->size;
2269 htab->sgot->size += GOT_ENTRY_SIZE;
2270 /* Reserve room for the initial entry.
2271 FIXME: we could probably do away with it in this case. */
2272 if (htab->splt->size == 0)
2273 htab->splt->size += PLT_ENTRY_SIZE;
2274 htab->tlsdesc_plt = htab->splt->size;
2275 htab->splt->size += PLT_ENTRY_SIZE;
2276 }
2277 }
2278
2279 /* We now have determined the sizes of the various dynamic sections.
2280 Allocate memory for them. */
2281 relocs = FALSE;
2282 for (s = dynobj->sections; s != NULL; s = s->next)
2283 {
2284 if ((s->flags & SEC_LINKER_CREATED) == 0)
2285 continue;
2286
2287 if (s == htab->splt
2288 || s == htab->sgot
2289 || s == htab->sgotplt
2290 || s == htab->iplt
2291 || s == htab->igotplt
2292 || s == htab->sdynbss)
2293 {
2294 /* Strip this section if we don't need it; see the
2295 comment below. */
2296 }
2297 else if (CONST_STRNEQ (bfd_get_section_name (dynobj, s), ".rela"))
2298 {
2299 if (s->size != 0 && s != htab->srelplt)
2300 relocs = TRUE;
2301
2302 /* We use the reloc_count field as a counter if we need
2303 to copy relocs into the output file. */
2304 if (s != htab->srelplt)
2305 s->reloc_count = 0;
2306 }
2307 else
2308 {
2309 /* It's not one of our sections, so don't allocate space. */
2310 continue;
2311 }
2312
2313 if (s->size == 0)
2314 {
2315 /* If we don't need this section, strip it from the
2316 output file. This is mostly to handle .rela.bss and
2317 .rela.plt. We must create both sections in
2318 create_dynamic_sections, because they must be created
2319 before the linker maps input sections to output
2320 sections. The linker does that before
2321 adjust_dynamic_symbol is called, and it is that
2322 function which decides whether anything needs to go
2323 into these sections. */
2324
2325 s->flags |= SEC_EXCLUDE;
2326 continue;
2327 }
2328
2329 if ((s->flags & SEC_HAS_CONTENTS) == 0)
2330 continue;
2331
2332 /* Allocate memory for the section contents. We use bfd_zalloc
2333 here in case unused entries are not reclaimed before the
2334 section's contents are written out. This should not happen,
2335 but this way if it does, we get a R_X86_64_NONE reloc instead
2336 of garbage. */
2337 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->size);
2338 if (s->contents == NULL)
2339 return FALSE;
2340 }
2341
2342 if (htab->elf.dynamic_sections_created)
2343 {
2344 /* Add some entries to the .dynamic section. We fill in the
2345 values later, in elf64_x86_64_finish_dynamic_sections, but we
2346 must add the entries now so that we get the correct size for
2347 the .dynamic section. The DT_DEBUG entry is filled in by the
2348 dynamic linker and used by the debugger. */
2349 #define add_dynamic_entry(TAG, VAL) \
2350 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
2351
2352 if (info->executable)
2353 {
2354 if (!add_dynamic_entry (DT_DEBUG, 0))
2355 return FALSE;
2356 }
2357
2358 if (htab->splt->size != 0)
2359 {
2360 if (!add_dynamic_entry (DT_PLTGOT, 0)
2361 || !add_dynamic_entry (DT_PLTRELSZ, 0)
2362 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
2363 || !add_dynamic_entry (DT_JMPREL, 0))
2364 return FALSE;
2365
2366 if (htab->tlsdesc_plt
2367 && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
2368 || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
2369 return FALSE;
2370 }
2371
2372 if (relocs)
2373 {
2374 if (!add_dynamic_entry (DT_RELA, 0)
2375 || !add_dynamic_entry (DT_RELASZ, 0)
2376 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
2377 return FALSE;
2378
2379 /* If any dynamic relocs apply to a read-only section,
2380 then we need a DT_TEXTREL entry. */
2381 if ((info->flags & DF_TEXTREL) == 0)
2382 elf_link_hash_traverse (&htab->elf,
2383 elf64_x86_64_readonly_dynrelocs,
2384 info);
2385
2386 if ((info->flags & DF_TEXTREL) != 0)
2387 {
2388 if (!add_dynamic_entry (DT_TEXTREL, 0))
2389 return FALSE;
2390 }
2391 }
2392 }
2393 #undef add_dynamic_entry
2394
2395 return TRUE;
2396 }
2397
2398 static bfd_boolean
2399 elf64_x86_64_always_size_sections (bfd *output_bfd,
2400 struct bfd_link_info *info)
2401 {
2402 asection *tls_sec = elf_hash_table (info)->tls_sec;
2403
2404 if (tls_sec)
2405 {
2406 struct elf_link_hash_entry *tlsbase;
2407
2408 tlsbase = elf_link_hash_lookup (elf_hash_table (info),
2409 "_TLS_MODULE_BASE_",
2410 FALSE, FALSE, FALSE);
2411
2412 if (tlsbase && tlsbase->type == STT_TLS)
2413 {
2414 struct bfd_link_hash_entry *bh = NULL;
2415 const struct elf_backend_data *bed
2416 = get_elf_backend_data (output_bfd);
2417
2418 if (!(_bfd_generic_link_add_one_symbol
2419 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL,
2420 tls_sec, 0, NULL, FALSE,
2421 bed->collect, &bh)))
2422 return FALSE;
2423
2424 elf64_x86_64_hash_table (info)->tls_module_base = bh;
2425
2426 tlsbase = (struct elf_link_hash_entry *)bh;
2427 tlsbase->def_regular = 1;
2428 tlsbase->other = STV_HIDDEN;
2429 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE);
2430 }
2431 }
2432
2433 return TRUE;
2434 }
2435
2436 /* _TLS_MODULE_BASE_ needs to be treated especially when linking
2437 executables. Rather than setting it to the beginning of the TLS
2438 section, we have to set it to the end. This function may be called
2439 multiple times, it is idempotent. */
2440
2441 static void
2442 elf64_x86_64_set_tls_module_base (struct bfd_link_info *info)
2443 {
2444 struct bfd_link_hash_entry *base;
2445
2446 if (!info->executable)
2447 return;
2448
2449 base = elf64_x86_64_hash_table (info)->tls_module_base;
2450
2451 if (!base)
2452 return;
2453
2454 base->u.def.value = elf_hash_table (info)->tls_size;
2455 }
2456
2457 /* Return the base VMA address which should be subtracted from real addresses
2458 when resolving @dtpoff relocation.
2459 This is PT_TLS segment p_vaddr. */
2460
2461 static bfd_vma
2462 elf64_x86_64_dtpoff_base (struct bfd_link_info *info)
2463 {
2464 /* If tls_sec is NULL, we should have signalled an error already. */
2465 if (elf_hash_table (info)->tls_sec == NULL)
2466 return 0;
2467 return elf_hash_table (info)->tls_sec->vma;
2468 }
2469
2470 /* Return the relocation value for @tpoff relocation
2471 if STT_TLS virtual address is ADDRESS. */
2472
2473 static bfd_vma
2474 elf64_x86_64_tpoff (struct bfd_link_info *info, bfd_vma address)
2475 {
2476 struct elf_link_hash_table *htab = elf_hash_table (info);
2477
2478 /* If tls_segment is NULL, we should have signalled an error already. */
2479 if (htab->tls_sec == NULL)
2480 return 0;
2481 return address - htab->tls_size - htab->tls_sec->vma;
2482 }
2483
2484 /* Is the instruction before OFFSET in CONTENTS a 32bit relative
2485 branch? */
2486
2487 static bfd_boolean
2488 is_32bit_relative_branch (bfd_byte *contents, bfd_vma offset)
2489 {
2490 /* Opcode Instruction
2491 0xe8 call
2492 0xe9 jump
2493 0x0f 0x8x conditional jump */
2494 return ((offset > 0
2495 && (contents [offset - 1] == 0xe8
2496 || contents [offset - 1] == 0xe9))
2497 || (offset > 1
2498 && contents [offset - 2] == 0x0f
2499 && (contents [offset - 1] & 0xf0) == 0x80));
2500 }
2501
2502 /* Relocate an x86_64 ELF section. */
2503
2504 static bfd_boolean
2505 elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
2506 bfd *input_bfd, asection *input_section,
2507 bfd_byte *contents, Elf_Internal_Rela *relocs,
2508 Elf_Internal_Sym *local_syms,
2509 asection **local_sections)
2510 {
2511 struct elf64_x86_64_link_hash_table *htab;
2512 Elf_Internal_Shdr *symtab_hdr;
2513 struct elf_link_hash_entry **sym_hashes;
2514 bfd_vma *local_got_offsets;
2515 bfd_vma *local_tlsdesc_gotents;
2516 Elf_Internal_Rela *rel;
2517 Elf_Internal_Rela *relend;
2518
2519 BFD_ASSERT (is_x86_64_elf (input_bfd));
2520
2521 htab = elf64_x86_64_hash_table (info);
2522 symtab_hdr = &elf_symtab_hdr (input_bfd);
2523 sym_hashes = elf_sym_hashes (input_bfd);
2524 local_got_offsets = elf_local_got_offsets (input_bfd);
2525 local_tlsdesc_gotents = elf64_x86_64_local_tlsdesc_gotent (input_bfd);
2526
2527 elf64_x86_64_set_tls_module_base (info);
2528
2529 rel = relocs;
2530 relend = relocs + input_section->reloc_count;
2531 for (; rel < relend; rel++)
2532 {
2533 unsigned int r_type;
2534 reloc_howto_type *howto;
2535 unsigned long r_symndx;
2536 struct elf_link_hash_entry *h;
2537 Elf_Internal_Sym *sym;
2538 asection *sec;
2539 bfd_vma off, offplt;
2540 bfd_vma relocation;
2541 bfd_boolean unresolved_reloc;
2542 bfd_reloc_status_type r;
2543 int tls_type;
2544 asection *base_got;
2545
2546 r_type = ELF64_R_TYPE (rel->r_info);
2547 if (r_type == (int) R_X86_64_GNU_VTINHERIT
2548 || r_type == (int) R_X86_64_GNU_VTENTRY)
2549 continue;
2550
2551 if (r_type >= R_X86_64_max)
2552 {
2553 bfd_set_error (bfd_error_bad_value);
2554 return FALSE;
2555 }
2556
2557 howto = x86_64_elf_howto_table + r_type;
2558 r_symndx = ELF64_R_SYM (rel->r_info);
2559 h = NULL;
2560 sym = NULL;
2561 sec = NULL;
2562 unresolved_reloc = FALSE;
2563 if (r_symndx < symtab_hdr->sh_info)
2564 {
2565 sym = local_syms + r_symndx;
2566 sec = local_sections[r_symndx];
2567
2568 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
2569 }
2570 else
2571 {
2572 bfd_boolean warned;
2573
2574 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
2575 r_symndx, symtab_hdr, sym_hashes,
2576 h, sec, relocation,
2577 unresolved_reloc, warned);
2578 }
2579
2580 if (sec != NULL && elf_discarded_section (sec))
2581 {
2582 /* For relocs against symbols from removed linkonce sections,
2583 or sections discarded by a linker script, we just want the
2584 section contents zeroed. Avoid any special processing. */
2585 _bfd_clear_contents (howto, input_bfd, contents + rel->r_offset);
2586 rel->r_info = 0;
2587 rel->r_addend = 0;
2588 continue;
2589 }
2590
2591 if (info->relocatable)
2592 continue;
2593
2594 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle
2595 it here if it is defined in a non-shared object. */
2596 if (h != NULL
2597 && h->type == STT_GNU_IFUNC
2598 && h->def_regular)
2599 {
2600 asection *plt;
2601 bfd_vma plt_index;
2602
2603 if ((input_section->flags & SEC_ALLOC) == 0
2604 || h->plt.offset == (bfd_vma) -1)
2605 abort ();
2606
2607 /* STT_GNU_IFUNC symbol must go through PLT. */
2608 plt = htab->splt ? htab->splt : htab->iplt;
2609 relocation = (plt->output_section->vma
2610 + plt->output_offset + h->plt.offset);
2611
2612 switch (r_type)
2613 {
2614 default:
2615 (*_bfd_error_handler)
2616 (_("%B: relocation %s against STT_GNU_IFUNC "
2617 "symbol `%s' isn't handled by %s"), input_bfd,
2618 x86_64_elf_howto_table[r_type].name,
2619 h->root.root.string, __FUNCTION__);
2620 bfd_set_error (bfd_error_bad_value);
2621 return FALSE;
2622
2623 case R_X86_64_32S:
2624 if (!info->executable)
2625 abort ();
2626
2627 case R_X86_64_32:
2628 case R_X86_64_64:
2629 case R_X86_64_PC32:
2630 case R_X86_64_PC64:
2631 case R_X86_64_PLT32:
2632 goto do_relocation;
2633
2634 case R_X86_64_GOTPCREL:
2635 case R_X86_64_GOTPCREL64:
2636 base_got = htab->sgot;
2637 off = h->got.offset;
2638
2639 if (base_got == NULL)
2640 abort ();
2641
2642 if (off == (bfd_vma) -1)
2643 {
2644 /* We can't use h->got.offset here to save state, or
2645 even just remember the offset, as finish_dynamic_symbol
2646 would use that as offset into .got. */
2647
2648 if (htab->splt != NULL)
2649 {
2650 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2651 off = (plt_index + 3) * GOT_ENTRY_SIZE;
2652 base_got = htab->sgotplt;
2653 }
2654 else
2655 {
2656 plt_index = h->plt.offset / PLT_ENTRY_SIZE;
2657 off = plt_index * GOT_ENTRY_SIZE;
2658 base_got = htab->igotplt;
2659 }
2660
2661 if (h->dynindx == -1
2662 || h->forced_local
2663 || info->symbolic)
2664 {
2665 /* This references the local defitionion. We must
2666 initialize this entry in the global offset table.
2667 Since the offset must always be a multiple of 8,
2668 we use the least significant bit to record
2669 whether we have initialized it already.
2670
2671 When doing a dynamic link, we create a .rela.got
2672 relocation entry to initialize the value. This
2673 is done in the finish_dynamic_symbol routine. */
2674 if ((off & 1) != 0)
2675 off &= ~1;
2676 else
2677 {
2678 bfd_put_64 (output_bfd, relocation,
2679 base_got->contents + off);
2680 /* Note that this is harmless for the GOTPLT64
2681 case, as -1 | 1 still is -1. */
2682 h->got.offset |= 1;
2683 }
2684 }
2685 }
2686
2687 relocation = (base_got->output_section->vma
2688 + base_got->output_offset + off);
2689
2690 if (r_type != R_X86_64_GOTPCREL
2691 && r_type != R_X86_64_GOTPCREL64)
2692 {
2693 asection *gotplt;
2694 if (htab->splt != NULL)
2695 gotplt = htab->sgotplt;
2696 else
2697 gotplt = htab->igotplt;
2698 relocation -= (gotplt->output_section->vma
2699 - gotplt->output_offset);
2700 }
2701
2702 goto do_relocation;
2703 }
2704 }
2705
2706 /* When generating a shared object, the relocations handled here are
2707 copied into the output file to be resolved at run time. */
2708 switch (r_type)
2709 {
2710 case R_X86_64_GOT32:
2711 case R_X86_64_GOT64:
2712 /* Relocation is to the entry for this symbol in the global
2713 offset table. */
2714 case R_X86_64_GOTPCREL:
2715 case R_X86_64_GOTPCREL64:
2716 /* Use global offset table entry as symbol value. */
2717 case R_X86_64_GOTPLT64:
2718 /* This is the same as GOT64 for relocation purposes, but
2719 indicates the existence of a PLT entry. The difficulty is,
2720 that we must calculate the GOT slot offset from the PLT
2721 offset, if this symbol got a PLT entry (it was global).
2722 Additionally if it's computed from the PLT entry, then that
2723 GOT offset is relative to .got.plt, not to .got. */
2724 base_got = htab->sgot;
2725
2726 if (htab->sgot == NULL)
2727 abort ();
2728
2729 if (h != NULL)
2730 {
2731 bfd_boolean dyn;
2732
2733 off = h->got.offset;
2734 if (h->needs_plt
2735 && h->plt.offset != (bfd_vma)-1
2736 && off == (bfd_vma)-1)
2737 {
2738 /* We can't use h->got.offset here to save
2739 state, or even just remember the offset, as
2740 finish_dynamic_symbol would use that as offset into
2741 .got. */
2742 bfd_vma plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2743 off = (plt_index + 3) * GOT_ENTRY_SIZE;
2744 base_got = htab->sgotplt;
2745 }
2746
2747 dyn = htab->elf.dynamic_sections_created;
2748
2749 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
2750 || (info->shared
2751 && SYMBOL_REFERENCES_LOCAL (info, h))
2752 || (ELF_ST_VISIBILITY (h->other)
2753 && h->root.type == bfd_link_hash_undefweak))
2754 {
2755 /* This is actually a static link, or it is a -Bsymbolic
2756 link and the symbol is defined locally, or the symbol
2757 was forced to be local because of a version file. We
2758 must initialize this entry in the global offset table.
2759 Since the offset must always be a multiple of 8, we
2760 use the least significant bit to record whether we
2761 have initialized it already.
2762
2763 When doing a dynamic link, we create a .rela.got
2764 relocation entry to initialize the value. This is
2765 done in the finish_dynamic_symbol routine. */
2766 if ((off & 1) != 0)
2767 off &= ~1;
2768 else
2769 {
2770 bfd_put_64 (output_bfd, relocation,
2771 base_got->contents + off);
2772 /* Note that this is harmless for the GOTPLT64 case,
2773 as -1 | 1 still is -1. */
2774 h->got.offset |= 1;
2775 }
2776 }
2777 else
2778 unresolved_reloc = FALSE;
2779 }
2780 else
2781 {
2782 if (local_got_offsets == NULL)
2783 abort ();
2784
2785 off = local_got_offsets[r_symndx];
2786
2787 /* The offset must always be a multiple of 8. We use
2788 the least significant bit to record whether we have
2789 already generated the necessary reloc. */
2790 if ((off & 1) != 0)
2791 off &= ~1;
2792 else
2793 {
2794 bfd_put_64 (output_bfd, relocation,
2795 base_got->contents + off);
2796
2797 if (info->shared)
2798 {
2799 asection *s;
2800 Elf_Internal_Rela outrel;
2801 bfd_byte *loc;
2802
2803 /* We need to generate a R_X86_64_RELATIVE reloc
2804 for the dynamic linker. */
2805 s = htab->srelgot;
2806 if (s == NULL)
2807 abort ();
2808
2809 outrel.r_offset = (base_got->output_section->vma
2810 + base_got->output_offset
2811 + off);
2812 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2813 outrel.r_addend = relocation;
2814 loc = s->contents;
2815 loc += s->reloc_count++ * sizeof (Elf64_External_Rela);
2816 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2817 }
2818
2819 local_got_offsets[r_symndx] |= 1;
2820 }
2821 }
2822
2823 if (off >= (bfd_vma) -2)
2824 abort ();
2825
2826 relocation = base_got->output_section->vma
2827 + base_got->output_offset + off;
2828 if (r_type != R_X86_64_GOTPCREL && r_type != R_X86_64_GOTPCREL64)
2829 relocation -= htab->sgotplt->output_section->vma
2830 - htab->sgotplt->output_offset;
2831
2832 break;
2833
2834 case R_X86_64_GOTOFF64:
2835 /* Relocation is relative to the start of the global offset
2836 table. */
2837
2838 /* Check to make sure it isn't a protected function symbol
2839 for shared library since it may not be local when used
2840 as function address. */
2841 if (info->shared
2842 && h
2843 && h->def_regular
2844 && h->type == STT_FUNC
2845 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
2846 {
2847 (*_bfd_error_handler)
2848 (_("%B: relocation R_X86_64_GOTOFF64 against protected function `%s' can not be used when making a shared object"),
2849 input_bfd, h->root.root.string);
2850 bfd_set_error (bfd_error_bad_value);
2851 return FALSE;
2852 }
2853
2854 /* Note that sgot is not involved in this
2855 calculation. We always want the start of .got.plt. If we
2856 defined _GLOBAL_OFFSET_TABLE_ in a different way, as is
2857 permitted by the ABI, we might have to change this
2858 calculation. */
2859 relocation -= htab->sgotplt->output_section->vma
2860 + htab->sgotplt->output_offset;
2861 break;
2862
2863 case R_X86_64_GOTPC32:
2864 case R_X86_64_GOTPC64:
2865 /* Use global offset table as symbol value. */
2866 relocation = htab->sgotplt->output_section->vma
2867 + htab->sgotplt->output_offset;
2868 unresolved_reloc = FALSE;
2869 break;
2870
2871 case R_X86_64_PLTOFF64:
2872 /* Relocation is PLT entry relative to GOT. For local
2873 symbols it's the symbol itself relative to GOT. */
2874 if (h != NULL
2875 /* See PLT32 handling. */
2876 && h->plt.offset != (bfd_vma) -1
2877 && htab->splt != NULL)
2878 {
2879 relocation = (htab->splt->output_section->vma
2880 + htab->splt->output_offset
2881 + h->plt.offset);
2882 unresolved_reloc = FALSE;
2883 }
2884
2885 relocation -= htab->sgotplt->output_section->vma
2886 + htab->sgotplt->output_offset;
2887 break;
2888
2889 case R_X86_64_PLT32:
2890 /* Relocation is to the entry for this symbol in the
2891 procedure linkage table. */
2892
2893 /* Resolve a PLT32 reloc against a local symbol directly,
2894 without using the procedure linkage table. */
2895 if (h == NULL)
2896 break;
2897
2898 if (h->plt.offset == (bfd_vma) -1
2899 || htab->splt == NULL)
2900 {
2901 /* We didn't make a PLT entry for this symbol. This
2902 happens when statically linking PIC code, or when
2903 using -Bsymbolic. */
2904 break;
2905 }
2906
2907 relocation = (htab->splt->output_section->vma
2908 + htab->splt->output_offset
2909 + h->plt.offset);
2910 unresolved_reloc = FALSE;
2911 break;
2912
2913 case R_X86_64_PC8:
2914 case R_X86_64_PC16:
2915 case R_X86_64_PC32:
2916 if (info->shared
2917 && (input_section->flags & SEC_ALLOC) != 0
2918 && (input_section->flags & SEC_READONLY) != 0
2919 && h != NULL)
2920 {
2921 bfd_boolean fail = FALSE;
2922 bfd_boolean branch
2923 = (r_type == R_X86_64_PC32
2924 && is_32bit_relative_branch (contents, rel->r_offset));
2925
2926 if (SYMBOL_REFERENCES_LOCAL (info, h))
2927 {
2928 /* Symbol is referenced locally. Make sure it is
2929 defined locally or for a branch. */
2930 fail = !h->def_regular && !branch;
2931 }
2932 else
2933 {
2934 /* Symbol isn't referenced locally. We only allow
2935 branch to symbol with non-default visibility. */
2936 fail = (!branch
2937 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT);
2938 }
2939
2940 if (fail)
2941 {
2942 const char *fmt;
2943 const char *v;
2944 const char *pic = "";
2945
2946 switch (ELF_ST_VISIBILITY (h->other))
2947 {
2948 case STV_HIDDEN:
2949 v = _("hidden symbol");
2950 break;
2951 case STV_INTERNAL:
2952 v = _("internal symbol");
2953 break;
2954 case STV_PROTECTED:
2955 v = _("protected symbol");
2956 break;
2957 default:
2958 v = _("symbol");
2959 pic = _("; recompile with -fPIC");
2960 break;
2961 }
2962
2963 if (h->def_regular)
2964 fmt = _("%B: relocation %s against %s `%s' can not be used when making a shared object%s");
2965 else
2966 fmt = _("%B: relocation %s against undefined %s `%s' can not be used when making a shared object%s");
2967
2968 (*_bfd_error_handler) (fmt, input_bfd,
2969 x86_64_elf_howto_table[r_type].name,
2970 v, h->root.root.string, pic);
2971 bfd_set_error (bfd_error_bad_value);
2972 return FALSE;
2973 }
2974 }
2975 /* Fall through. */
2976
2977 case R_X86_64_8:
2978 case R_X86_64_16:
2979 case R_X86_64_32:
2980 case R_X86_64_PC64:
2981 case R_X86_64_64:
2982 /* FIXME: The ABI says the linker should make sure the value is
2983 the same when it's zeroextended to 64 bit. */
2984
2985 if ((input_section->flags & SEC_ALLOC) == 0)
2986 break;
2987
2988 if ((info->shared
2989 && (h == NULL
2990 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
2991 || h->root.type != bfd_link_hash_undefweak)
2992 && (! IS_X86_64_PCREL_TYPE (r_type)
2993 || ! SYMBOL_CALLS_LOCAL (info, h)))
2994 || (ELIMINATE_COPY_RELOCS
2995 && !info->shared
2996 && h != NULL
2997 && h->dynindx != -1
2998 && !h->non_got_ref
2999 && ((h->def_dynamic
3000 && !h->def_regular)
3001 || h->root.type == bfd_link_hash_undefweak
3002 || h->root.type == bfd_link_hash_undefined)))
3003 {
3004 Elf_Internal_Rela outrel;
3005 bfd_byte *loc;
3006 bfd_boolean skip, relocate;
3007 asection *sreloc;
3008
3009 /* When generating a shared object, these relocations
3010 are copied into the output file to be resolved at run
3011 time. */
3012 skip = FALSE;
3013 relocate = FALSE;
3014
3015 outrel.r_offset =
3016 _bfd_elf_section_offset (output_bfd, info, input_section,
3017 rel->r_offset);
3018 if (outrel.r_offset == (bfd_vma) -1)
3019 skip = TRUE;
3020 else if (outrel.r_offset == (bfd_vma) -2)
3021 skip = TRUE, relocate = TRUE;
3022
3023 outrel.r_offset += (input_section->output_section->vma
3024 + input_section->output_offset);
3025
3026 if (skip)
3027 memset (&outrel, 0, sizeof outrel);
3028
3029 /* h->dynindx may be -1 if this symbol was marked to
3030 become local. */
3031 else if (h != NULL
3032 && h->dynindx != -1
3033 && (IS_X86_64_PCREL_TYPE (r_type)
3034 || ! info->shared
3035 || ! SYMBOLIC_BIND (info, h)
3036 || ! h->def_regular))
3037 {
3038 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
3039 outrel.r_addend = rel->r_addend;
3040 }
3041 else
3042 {
3043 /* This symbol is local, or marked to become local. */
3044 if (r_type == R_X86_64_64)
3045 {
3046 relocate = TRUE;
3047 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
3048 outrel.r_addend = relocation + rel->r_addend;
3049 }
3050 else
3051 {
3052 long sindx;
3053
3054 if (bfd_is_abs_section (sec))
3055 sindx = 0;
3056 else if (sec == NULL || sec->owner == NULL)
3057 {
3058 bfd_set_error (bfd_error_bad_value);
3059 return FALSE;
3060 }
3061 else
3062 {
3063 asection *osec;
3064
3065 /* We are turning this relocation into one
3066 against a section symbol. It would be
3067 proper to subtract the symbol's value,
3068 osec->vma, from the emitted reloc addend,
3069 but ld.so expects buggy relocs. */
3070 osec = sec->output_section;
3071 sindx = elf_section_data (osec)->dynindx;
3072 if (sindx == 0)
3073 {
3074 asection *oi = htab->elf.text_index_section;
3075 sindx = elf_section_data (oi)->dynindx;
3076 }
3077 BFD_ASSERT (sindx != 0);
3078 }
3079
3080 outrel.r_info = ELF64_R_INFO (sindx, r_type);
3081 outrel.r_addend = relocation + rel->r_addend;
3082 }
3083 }
3084
3085 sreloc = elf_section_data (input_section)->sreloc;
3086
3087 BFD_ASSERT (sreloc != NULL && sreloc->contents != NULL);
3088
3089 loc = sreloc->contents;
3090 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
3091 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
3092
3093 /* If this reloc is against an external symbol, we do
3094 not want to fiddle with the addend. Otherwise, we
3095 need to include the symbol value so that it becomes
3096 an addend for the dynamic reloc. */
3097 if (! relocate)
3098 continue;
3099 }
3100
3101 break;
3102
3103 case R_X86_64_TLSGD:
3104 case R_X86_64_GOTPC32_TLSDESC:
3105 case R_X86_64_TLSDESC_CALL:
3106 case R_X86_64_GOTTPOFF:
3107 tls_type = GOT_UNKNOWN;
3108 if (h == NULL && local_got_offsets)
3109 tls_type = elf64_x86_64_local_got_tls_type (input_bfd) [r_symndx];
3110 else if (h != NULL)
3111 tls_type = elf64_x86_64_hash_entry (h)->tls_type;
3112
3113 if (! elf64_x86_64_tls_transition (info, input_bfd,
3114 input_section, contents,
3115 symtab_hdr, sym_hashes,
3116 &r_type, tls_type, rel,
3117 relend, h))
3118 return FALSE;
3119
3120 if (r_type == R_X86_64_TPOFF32)
3121 {
3122 bfd_vma roff = rel->r_offset;
3123
3124 BFD_ASSERT (! unresolved_reloc);
3125
3126 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
3127 {
3128 /* GD->LE transition.
3129 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
3130 .word 0x6666; rex64; call __tls_get_addr
3131 Change it into:
3132 movq %fs:0, %rax
3133 leaq foo@tpoff(%rax), %rax */
3134 memcpy (contents + roff - 4,
3135 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0",
3136 16);
3137 bfd_put_32 (output_bfd,
3138 elf64_x86_64_tpoff (info, relocation),
3139 contents + roff + 8);
3140 /* Skip R_X86_64_PC32/R_X86_64_PLT32. */
3141 rel++;
3142 continue;
3143 }
3144 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTPC32_TLSDESC)
3145 {
3146 /* GDesc -> LE transition.
3147 It's originally something like:
3148 leaq x@tlsdesc(%rip), %rax
3149
3150 Change it to:
3151 movl $x@tpoff, %rax
3152 */
3153
3154 unsigned int val, type, type2;
3155
3156 type = bfd_get_8 (input_bfd, contents + roff - 3);
3157 type2 = bfd_get_8 (input_bfd, contents + roff - 2);
3158 val = bfd_get_8 (input_bfd, contents + roff - 1);
3159 bfd_put_8 (output_bfd, 0x48 | ((type >> 2) & 1),
3160 contents + roff - 3);
3161 bfd_put_8 (output_bfd, 0xc7, contents + roff - 2);
3162 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7),
3163 contents + roff - 1);
3164 bfd_put_32 (output_bfd,
3165 elf64_x86_64_tpoff (info, relocation),
3166 contents + roff);
3167 continue;
3168 }
3169 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSDESC_CALL)
3170 {
3171 /* GDesc -> LE transition.
3172 It's originally:
3173 call *(%rax)
3174 Turn it into:
3175 xchg %ax,%ax. */
3176 bfd_put_8 (output_bfd, 0x66, contents + roff);
3177 bfd_put_8 (output_bfd, 0x90, contents + roff + 1);
3178 continue;
3179 }
3180 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTTPOFF)
3181 {
3182 /* IE->LE transition:
3183 Originally it can be one of:
3184 movq foo@gottpoff(%rip), %reg
3185 addq foo@gottpoff(%rip), %reg
3186 We change it into:
3187 movq $foo, %reg
3188 leaq foo(%reg), %reg
3189 addq $foo, %reg. */
3190
3191 unsigned int val, type, reg;
3192
3193 val = bfd_get_8 (input_bfd, contents + roff - 3);
3194 type = bfd_get_8 (input_bfd, contents + roff - 2);
3195 reg = bfd_get_8 (input_bfd, contents + roff - 1);
3196 reg >>= 3;
3197 if (type == 0x8b)
3198 {
3199 /* movq */
3200 if (val == 0x4c)
3201 bfd_put_8 (output_bfd, 0x49,
3202 contents + roff - 3);
3203 bfd_put_8 (output_bfd, 0xc7,
3204 contents + roff - 2);
3205 bfd_put_8 (output_bfd, 0xc0 | reg,
3206 contents + roff - 1);
3207 }
3208 else if (reg == 4)
3209 {
3210 /* addq -> addq - addressing with %rsp/%r12 is
3211 special */
3212 if (val == 0x4c)
3213 bfd_put_8 (output_bfd, 0x49,
3214 contents + roff - 3);
3215 bfd_put_8 (output_bfd, 0x81,
3216 contents + roff - 2);
3217 bfd_put_8 (output_bfd, 0xc0 | reg,
3218 contents + roff - 1);
3219 }
3220 else
3221 {
3222 /* addq -> leaq */
3223 if (val == 0x4c)
3224 bfd_put_8 (output_bfd, 0x4d,
3225 contents + roff - 3);
3226 bfd_put_8 (output_bfd, 0x8d,
3227 contents + roff - 2);
3228 bfd_put_8 (output_bfd, 0x80 | reg | (reg << 3),
3229 contents + roff - 1);
3230 }
3231 bfd_put_32 (output_bfd,
3232 elf64_x86_64_tpoff (info, relocation),
3233 contents + roff);
3234 continue;
3235 }
3236 else
3237 BFD_ASSERT (FALSE);
3238 }
3239
3240 if (htab->sgot == NULL)
3241 abort ();
3242
3243 if (h != NULL)
3244 {
3245 off = h->got.offset;
3246 offplt = elf64_x86_64_hash_entry (h)->tlsdesc_got;
3247 }
3248 else
3249 {
3250 if (local_got_offsets == NULL)
3251 abort ();
3252
3253 off = local_got_offsets[r_symndx];
3254 offplt = local_tlsdesc_gotents[r_symndx];
3255 }
3256
3257 if ((off & 1) != 0)
3258 off &= ~1;
3259 else
3260 {
3261 Elf_Internal_Rela outrel;
3262 bfd_byte *loc;
3263 int dr_type, indx;
3264 asection *sreloc;
3265
3266 if (htab->srelgot == NULL)
3267 abort ();
3268
3269 indx = h && h->dynindx != -1 ? h->dynindx : 0;
3270
3271 if (GOT_TLS_GDESC_P (tls_type))
3272 {
3273 outrel.r_info = ELF64_R_INFO (indx, R_X86_64_TLSDESC);
3274 BFD_ASSERT (htab->sgotplt_jump_table_size + offplt
3275 + 2 * GOT_ENTRY_SIZE <= htab->sgotplt->size);
3276 outrel.r_offset = (htab->sgotplt->output_section->vma
3277 + htab->sgotplt->output_offset
3278 + offplt
3279 + htab->sgotplt_jump_table_size);
3280 sreloc = htab->srelplt;
3281 loc = sreloc->contents;
3282 loc += sreloc->reloc_count++
3283 * sizeof (Elf64_External_Rela);
3284 BFD_ASSERT (loc + sizeof (Elf64_External_Rela)
3285 <= sreloc->contents + sreloc->size);
3286 if (indx == 0)
3287 outrel.r_addend = relocation - elf64_x86_64_dtpoff_base (info);
3288 else
3289 outrel.r_addend = 0;
3290 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
3291 }
3292
3293 sreloc = htab->srelgot;
3294
3295 outrel.r_offset = (htab->sgot->output_section->vma
3296 + htab->sgot->output_offset + off);
3297
3298 if (GOT_TLS_GD_P (tls_type))
3299 dr_type = R_X86_64_DTPMOD64;
3300 else if (GOT_TLS_GDESC_P (tls_type))
3301 goto dr_done;
3302 else
3303 dr_type = R_X86_64_TPOFF64;
3304
3305 bfd_put_64 (output_bfd, 0, htab->sgot->contents + off);
3306 outrel.r_addend = 0;
3307 if ((dr_type == R_X86_64_TPOFF64
3308 || dr_type == R_X86_64_TLSDESC) && indx == 0)
3309 outrel.r_addend = relocation - elf64_x86_64_dtpoff_base (info);
3310 outrel.r_info = ELF64_R_INFO (indx, dr_type);
3311
3312 loc = sreloc->contents;
3313 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
3314 BFD_ASSERT (loc + sizeof (Elf64_External_Rela)
3315 <= sreloc->contents + sreloc->size);
3316 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
3317
3318 if (GOT_TLS_GD_P (tls_type))
3319 {
3320 if (indx == 0)
3321 {
3322 BFD_ASSERT (! unresolved_reloc);
3323 bfd_put_64 (output_bfd,
3324 relocation - elf64_x86_64_dtpoff_base (info),
3325 htab->sgot->contents + off + GOT_ENTRY_SIZE);
3326 }
3327 else
3328 {
3329 bfd_put_64 (output_bfd, 0,
3330 htab->sgot->contents + off + GOT_ENTRY_SIZE);
3331 outrel.r_info = ELF64_R_INFO (indx,
3332 R_X86_64_DTPOFF64);
3333 outrel.r_offset += GOT_ENTRY_SIZE;
3334 sreloc->reloc_count++;
3335 loc += sizeof (Elf64_External_Rela);
3336 BFD_ASSERT (loc + sizeof (Elf64_External_Rela)
3337 <= sreloc->contents + sreloc->size);
3338 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
3339 }
3340 }
3341
3342 dr_done:
3343 if (h != NULL)
3344 h->got.offset |= 1;
3345 else
3346 local_got_offsets[r_symndx] |= 1;
3347 }
3348
3349 if (off >= (bfd_vma) -2
3350 && ! GOT_TLS_GDESC_P (tls_type))
3351 abort ();
3352 if (r_type == ELF64_R_TYPE (rel->r_info))
3353 {
3354 if (r_type == R_X86_64_GOTPC32_TLSDESC
3355 || r_type == R_X86_64_TLSDESC_CALL)
3356 relocation = htab->sgotplt->output_section->vma
3357 + htab->sgotplt->output_offset
3358 + offplt + htab->sgotplt_jump_table_size;
3359 else
3360 relocation = htab->sgot->output_section->vma
3361 + htab->sgot->output_offset + off;
3362 unresolved_reloc = FALSE;
3363 }
3364 else
3365 {
3366 bfd_vma roff = rel->r_offset;
3367
3368 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
3369 {
3370 /* GD->IE transition.
3371 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
3372 .word 0x6666; rex64; call __tls_get_addr@plt
3373 Change it into:
3374 movq %fs:0, %rax
3375 addq foo@gottpoff(%rip), %rax */
3376 memcpy (contents + roff - 4,
3377 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0",
3378 16);
3379
3380 relocation = (htab->sgot->output_section->vma
3381 + htab->sgot->output_offset + off
3382 - roff
3383 - input_section->output_section->vma
3384 - input_section->output_offset
3385 - 12);
3386 bfd_put_32 (output_bfd, relocation,
3387 contents + roff + 8);
3388 /* Skip R_X86_64_PLT32. */
3389 rel++;
3390 continue;
3391 }
3392 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTPC32_TLSDESC)
3393 {
3394 /* GDesc -> IE transition.
3395 It's originally something like:
3396 leaq x@tlsdesc(%rip), %rax
3397
3398 Change it to:
3399 movq x@gottpoff(%rip), %rax # before xchg %ax,%ax
3400 */
3401
3402 unsigned int val, type, type2;
3403
3404 type = bfd_get_8 (input_bfd, contents + roff - 3);
3405 type2 = bfd_get_8 (input_bfd, contents + roff - 2);
3406 val = bfd_get_8 (input_bfd, contents + roff - 1);
3407
3408 /* Now modify the instruction as appropriate. To
3409 turn a leaq into a movq in the form we use it, it
3410 suffices to change the second byte from 0x8d to
3411 0x8b. */
3412 bfd_put_8 (output_bfd, 0x8b, contents + roff - 2);
3413
3414 bfd_put_32 (output_bfd,
3415 htab->sgot->output_section->vma
3416 + htab->sgot->output_offset + off
3417 - rel->r_offset
3418 - input_section->output_section->vma
3419 - input_section->output_offset
3420 - 4,
3421 contents + roff);
3422 continue;
3423 }
3424 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSDESC_CALL)
3425 {
3426 /* GDesc -> IE transition.
3427 It's originally:
3428 call *(%rax)
3429
3430 Change it to:
3431 xchg %ax,%ax. */
3432
3433 unsigned int val, type;
3434
3435 type = bfd_get_8 (input_bfd, contents + roff);
3436 val = bfd_get_8 (input_bfd, contents + roff + 1);
3437 bfd_put_8 (output_bfd, 0x66, contents + roff);
3438 bfd_put_8 (output_bfd, 0x90, contents + roff + 1);
3439 continue;
3440 }
3441 else
3442 BFD_ASSERT (FALSE);
3443 }
3444 break;
3445
3446 case R_X86_64_TLSLD:
3447 if (! elf64_x86_64_tls_transition (info, input_bfd,
3448 input_section, contents,
3449 symtab_hdr, sym_hashes,
3450 &r_type, GOT_UNKNOWN,
3451 rel, relend, h))
3452 return FALSE;
3453
3454 if (r_type != R_X86_64_TLSLD)
3455 {
3456 /* LD->LE transition:
3457 leaq foo@tlsld(%rip), %rdi; call __tls_get_addr.
3458 We change it into:
3459 .word 0x6666; .byte 0x66; movl %fs:0, %rax. */
3460
3461 BFD_ASSERT (r_type == R_X86_64_TPOFF32);
3462 memcpy (contents + rel->r_offset - 3,
3463 "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0", 12);
3464 /* Skip R_X86_64_PC32/R_X86_64_PLT32. */
3465 rel++;
3466 continue;
3467 }
3468
3469 if (htab->sgot == NULL)
3470 abort ();
3471
3472 off = htab->tls_ld_got.offset;
3473 if (off & 1)
3474 off &= ~1;
3475 else
3476 {
3477 Elf_Internal_Rela outrel;
3478 bfd_byte *loc;
3479
3480 if (htab->srelgot == NULL)
3481 abort ();
3482
3483 outrel.r_offset = (htab->sgot->output_section->vma
3484 + htab->sgot->output_offset + off);
3485
3486 bfd_put_64 (output_bfd, 0,
3487 htab->sgot->contents + off);
3488 bfd_put_64 (output_bfd, 0,
3489 htab->sgot->contents + off + GOT_ENTRY_SIZE);
3490 outrel.r_info = ELF64_R_INFO (0, R_X86_64_DTPMOD64);
3491 outrel.r_addend = 0;
3492 loc = htab->srelgot->contents;
3493 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
3494 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
3495 htab->tls_ld_got.offset |= 1;
3496 }
3497 relocation = htab->sgot->output_section->vma
3498 + htab->sgot->output_offset + off;
3499 unresolved_reloc = FALSE;
3500 break;
3501
3502 case R_X86_64_DTPOFF32:
3503 if (info->shared || (input_section->flags & SEC_CODE) == 0)
3504 relocation -= elf64_x86_64_dtpoff_base (info);
3505 else
3506 relocation = elf64_x86_64_tpoff (info, relocation);
3507 break;
3508
3509 case R_X86_64_TPOFF32:
3510 BFD_ASSERT (! info->shared);
3511 relocation = elf64_x86_64_tpoff (info, relocation);
3512 break;
3513
3514 default:
3515 break;
3516 }
3517
3518 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
3519 because such sections are not SEC_ALLOC and thus ld.so will
3520 not process them. */
3521 if (unresolved_reloc
3522 && !((input_section->flags & SEC_DEBUGGING) != 0
3523 && h->def_dynamic))
3524 (*_bfd_error_handler)
3525 (_("%B(%A+0x%lx): unresolvable %s relocation against symbol `%s'"),
3526 input_bfd,
3527 input_section,
3528 (long) rel->r_offset,
3529 howto->name,
3530 h->root.root.string);
3531
3532 do_relocation:
3533 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
3534 contents, rel->r_offset,
3535 relocation, rel->r_addend);
3536
3537 if (r != bfd_reloc_ok)
3538 {
3539 const char *name;
3540
3541 if (h != NULL)
3542 name = h->root.root.string;
3543 else
3544 {
3545 name = bfd_elf_string_from_elf_section (input_bfd,
3546 symtab_hdr->sh_link,
3547 sym->st_name);
3548 if (name == NULL)
3549 return FALSE;
3550 if (*name == '\0')
3551 name = bfd_section_name (input_bfd, sec);
3552 }
3553
3554 if (r == bfd_reloc_overflow)
3555 {
3556 if (! ((*info->callbacks->reloc_overflow)
3557 (info, (h ? &h->root : NULL), name, howto->name,
3558 (bfd_vma) 0, input_bfd, input_section,
3559 rel->r_offset)))
3560 return FALSE;
3561 }
3562 else
3563 {
3564 (*_bfd_error_handler)
3565 (_("%B(%A+0x%lx): reloc against `%s': error %d"),
3566 input_bfd, input_section,
3567 (long) rel->r_offset, name, (int) r);
3568 return FALSE;
3569 }
3570 }
3571 }
3572
3573 return TRUE;
3574 }
3575
3576 /* Finish up dynamic symbol handling. We set the contents of various
3577 dynamic sections here. */
3578
3579 static bfd_boolean
3580 elf64_x86_64_finish_dynamic_symbol (bfd *output_bfd,
3581 struct bfd_link_info *info,
3582 struct elf_link_hash_entry *h,
3583 Elf_Internal_Sym *sym)
3584 {
3585 struct elf64_x86_64_link_hash_table *htab;
3586
3587 htab = elf64_x86_64_hash_table (info);
3588
3589 if (h->plt.offset != (bfd_vma) -1)
3590 {
3591 bfd_vma plt_index;
3592 bfd_vma got_offset;
3593 Elf_Internal_Rela rela;
3594 bfd_byte *loc;
3595 asection *plt, *gotplt, *relplt;
3596
3597 /* When building a static executable, use .iplt, .igot.plt and
3598 .rela.iplt sections for STT_GNU_IFUNC symbols. */
3599 if (htab->splt != 0)
3600 {
3601 plt = htab->splt;
3602 gotplt = htab->sgotplt;
3603 relplt = htab->srelplt;
3604 }
3605 else
3606 {
3607 plt = htab->iplt;
3608 gotplt = htab->igotplt;
3609 relplt = htab->irelplt;
3610 }
3611
3612 /* This symbol has an entry in the procedure linkage table. Set
3613 it up. */
3614 if ((h->dynindx == -1
3615 && !((h->forced_local || info->executable)
3616 && h->def_regular
3617 && h->type == STT_GNU_IFUNC))
3618 || plt == NULL
3619 || gotplt == NULL
3620 || relplt == NULL)
3621 abort ();
3622
3623 /* Get the index in the procedure linkage table which
3624 corresponds to this symbol. This is the index of this symbol
3625 in all the symbols for which we are making plt entries. The
3626 first entry in the procedure linkage table is reserved.
3627
3628 Get the offset into the .got table of the entry that
3629 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
3630 bytes. The first three are reserved for the dynamic linker.
3631
3632 For static executables, we don't reserve anything. */
3633
3634 if (plt == htab->splt)
3635 {
3636 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
3637 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
3638 }
3639 else
3640 {
3641 plt_index = h->plt.offset / PLT_ENTRY_SIZE;
3642 got_offset = plt_index * GOT_ENTRY_SIZE;
3643 }
3644
3645 /* Fill in the entry in the procedure linkage table. */
3646 memcpy (plt->contents + h->plt.offset, elf64_x86_64_plt_entry,
3647 PLT_ENTRY_SIZE);
3648
3649 /* Insert the relocation positions of the plt section. The magic
3650 numbers at the end of the statements are the positions of the
3651 relocations in the plt section. */
3652 /* Put offset for jmp *name@GOTPCREL(%rip), since the
3653 instruction uses 6 bytes, subtract this value. */
3654 bfd_put_32 (output_bfd,
3655 (gotplt->output_section->vma
3656 + gotplt->output_offset
3657 + got_offset
3658 - plt->output_section->vma
3659 - plt->output_offset
3660 - h->plt.offset
3661 - 6),
3662 plt->contents + h->plt.offset + 2);
3663
3664 /* Don't fill PLT entry for static executables. */
3665 if (plt == htab->splt)
3666 {
3667 /* Put relocation index. */
3668 bfd_put_32 (output_bfd, plt_index,
3669 plt->contents + h->plt.offset + 7);
3670 /* Put offset for jmp .PLT0. */
3671 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
3672 plt->contents + h->plt.offset + 12);
3673 }
3674
3675 /* Fill in the entry in the global offset table, initially this
3676 points to the pushq instruction in the PLT which is at offset 6. */
3677 bfd_put_64 (output_bfd, (plt->output_section->vma
3678 + plt->output_offset
3679 + h->plt.offset + 6),
3680 gotplt->contents + got_offset);
3681
3682 /* Fill in the entry in the .rela.plt section. */
3683 rela.r_offset = (gotplt->output_section->vma
3684 + gotplt->output_offset
3685 + got_offset);
3686 if (h->dynindx == -1
3687 || ((info->executable
3688 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
3689 && h->def_regular
3690 && h->type == STT_GNU_IFUNC))
3691 {
3692 /* If an STT_GNU_IFUNC symbol is locally defined, generate
3693 R_X86_64_IRELATIVE instead of R_X86_64_JUMP_SLOT. */
3694 rela.r_info = ELF64_R_INFO (0, R_X86_64_IRELATIVE);
3695 rela.r_addend = (h->root.u.def.value
3696 + h->root.u.def.section->output_section->vma
3697 + h->root.u.def.section->output_offset);
3698 }
3699 else
3700 {
3701 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
3702 rela.r_addend = 0;
3703 }
3704 loc = relplt->contents + plt_index * sizeof (Elf64_External_Rela);
3705 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
3706
3707 if (!h->def_regular)
3708 {
3709 /* Mark the symbol as undefined, rather than as defined in
3710 the .plt section. Leave the value if there were any
3711 relocations where pointer equality matters (this is a clue
3712 for the dynamic linker, to make function pointer
3713 comparisons work between an application and shared
3714 library), otherwise set it to zero. If a function is only
3715 called from a binary, there is no need to slow down
3716 shared libraries because of that. */
3717 sym->st_shndx = SHN_UNDEF;
3718 if (!h->pointer_equality_needed)
3719 sym->st_value = 0;
3720 }
3721 }
3722
3723 if (h->got.offset != (bfd_vma) -1
3724 && ! GOT_TLS_GD_ANY_P (elf64_x86_64_hash_entry (h)->tls_type)
3725 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE)
3726 {
3727 Elf_Internal_Rela rela;
3728 bfd_byte *loc;
3729
3730 /* This symbol has an entry in the global offset table. Set it
3731 up. */
3732 if (htab->sgot == NULL || htab->srelgot == NULL)
3733 abort ();
3734
3735 rela.r_offset = (htab->sgot->output_section->vma
3736 + htab->sgot->output_offset
3737 + (h->got.offset &~ (bfd_vma) 1));
3738
3739 /* If this is a static link, or it is a -Bsymbolic link and the
3740 symbol is defined locally or was forced to be local because
3741 of a version file, we just want to emit a RELATIVE reloc.
3742 The entry in the global offset table will already have been
3743 initialized in the relocate_section function. */
3744 if ((info->executable
3745 || info->symbolic
3746 || h->forced_local)
3747 && h->def_regular
3748 && h->pointer_equality_needed
3749 && h->type == STT_GNU_IFUNC)
3750 {
3751 /* The STT_GNU_IFUNC symbol is locally defined. But we can't
3752 use .got.plt, which contains the real function addres,
3753 since we need pointer equality. We load the GOT entry
3754 with the PLT entry without relocation. */
3755 asection *plt = htab->splt ? htab->splt : htab->iplt;
3756 if (htab->sgot == NULL
3757 || h->plt.offset == (bfd_vma) -1)
3758 abort ();
3759 bfd_put_64 (output_bfd, (plt->output_section->vma
3760 + plt->output_offset + h->plt.offset),
3761 htab->sgot->contents + h->got.offset);
3762 return TRUE;
3763 }
3764 else if (info->shared
3765 && SYMBOL_REFERENCES_LOCAL (info, h))
3766 {
3767 if (!h->def_regular)
3768 return FALSE;
3769 BFD_ASSERT((h->got.offset & 1) != 0);
3770 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
3771 rela.r_addend = (h->root.u.def.value
3772 + h->root.u.def.section->output_section->vma
3773 + h->root.u.def.section->output_offset);
3774 }
3775 else
3776 {
3777 BFD_ASSERT((h->got.offset & 1) == 0);
3778 bfd_put_64 (output_bfd, (bfd_vma) 0,
3779 htab->sgot->contents + h->got.offset);
3780 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
3781 rela.r_addend = 0;
3782 }
3783
3784 loc = htab->srelgot->contents;
3785 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
3786 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
3787 }
3788
3789 if (h->needs_copy)
3790 {
3791 Elf_Internal_Rela rela;
3792 bfd_byte *loc;
3793
3794 /* This symbol needs a copy reloc. Set it up. */
3795
3796 if (h->dynindx == -1
3797 || (h->root.type != bfd_link_hash_defined
3798 && h->root.type != bfd_link_hash_defweak)
3799 || htab->srelbss == NULL)
3800 abort ();
3801
3802 rela.r_offset = (h->root.u.def.value
3803 + h->root.u.def.section->output_section->vma
3804 + h->root.u.def.section->output_offset);
3805 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
3806 rela.r_addend = 0;
3807 loc = htab->srelbss->contents;
3808 loc += htab->srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
3809 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
3810 }
3811
3812 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
3813 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
3814 || h == htab->elf.hgot)
3815 sym->st_shndx = SHN_ABS;
3816
3817 return TRUE;
3818 }
3819
3820 /* Used to decide how to sort relocs in an optimal manner for the
3821 dynamic linker, before writing them out. */
3822
3823 static enum elf_reloc_type_class
3824 elf64_x86_64_reloc_type_class (const Elf_Internal_Rela *rela)
3825 {
3826 switch ((int) ELF64_R_TYPE (rela->r_info))
3827 {
3828 case R_X86_64_RELATIVE:
3829 return reloc_class_relative;
3830 case R_X86_64_JUMP_SLOT:
3831 return reloc_class_plt;
3832 case R_X86_64_COPY:
3833 return reloc_class_copy;
3834 default:
3835 return reloc_class_normal;
3836 }
3837 }
3838
3839 /* Finish up the dynamic sections. */
3840
3841 static bfd_boolean
3842 elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
3843 {
3844 struct elf64_x86_64_link_hash_table *htab;
3845 bfd *dynobj;
3846 asection *sdyn;
3847
3848 htab = elf64_x86_64_hash_table (info);
3849 dynobj = htab->elf.dynobj;
3850 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3851
3852 if (htab->elf.dynamic_sections_created)
3853 {
3854 Elf64_External_Dyn *dyncon, *dynconend;
3855
3856 if (sdyn == NULL || htab->sgot == NULL)
3857 abort ();
3858
3859 dyncon = (Elf64_External_Dyn *) sdyn->contents;
3860 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->size);
3861 for (; dyncon < dynconend; dyncon++)
3862 {
3863 Elf_Internal_Dyn dyn;
3864 asection *s;
3865
3866 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
3867
3868 switch (dyn.d_tag)
3869 {
3870 default:
3871 continue;
3872
3873 case DT_PLTGOT:
3874 s = htab->sgotplt;
3875 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
3876 break;
3877
3878 case DT_JMPREL:
3879 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
3880 break;
3881
3882 case DT_PLTRELSZ:
3883 s = htab->srelplt->output_section;
3884 dyn.d_un.d_val = s->size;
3885 break;
3886
3887 case DT_RELASZ:
3888 /* The procedure linkage table relocs (DT_JMPREL) should
3889 not be included in the overall relocs (DT_RELA).
3890 Therefore, we override the DT_RELASZ entry here to
3891 make it not include the JMPREL relocs. Since the
3892 linker script arranges for .rela.plt to follow all
3893 other relocation sections, we don't have to worry
3894 about changing the DT_RELA entry. */
3895 if (htab->srelplt != NULL)
3896 {
3897 s = htab->srelplt->output_section;
3898 dyn.d_un.d_val -= s->size;
3899 }
3900 break;
3901
3902 case DT_TLSDESC_PLT:
3903 s = htab->splt;
3904 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset
3905 + htab->tlsdesc_plt;
3906 break;
3907
3908 case DT_TLSDESC_GOT:
3909 s = htab->sgot;
3910 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset
3911 + htab->tlsdesc_got;
3912 break;
3913 }
3914
3915 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
3916 }
3917
3918 /* Fill in the special first entry in the procedure linkage table. */
3919 if (htab->splt && htab->splt->size > 0)
3920 {
3921 /* Fill in the first entry in the procedure linkage table. */
3922 memcpy (htab->splt->contents, elf64_x86_64_plt0_entry,
3923 PLT_ENTRY_SIZE);
3924 /* Add offset for pushq GOT+8(%rip), since the instruction
3925 uses 6 bytes subtract this value. */
3926 bfd_put_32 (output_bfd,
3927 (htab->sgotplt->output_section->vma
3928 + htab->sgotplt->output_offset
3929 + 8
3930 - htab->splt->output_section->vma
3931 - htab->splt->output_offset
3932 - 6),
3933 htab->splt->contents + 2);
3934 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
3935 the end of the instruction. */
3936 bfd_put_32 (output_bfd,
3937 (htab->sgotplt->output_section->vma
3938 + htab->sgotplt->output_offset
3939 + 16
3940 - htab->splt->output_section->vma
3941 - htab->splt->output_offset
3942 - 12),
3943 htab->splt->contents + 8);
3944
3945 elf_section_data (htab->splt->output_section)->this_hdr.sh_entsize =
3946 PLT_ENTRY_SIZE;
3947
3948 if (htab->tlsdesc_plt)
3949 {
3950 bfd_put_64 (output_bfd, (bfd_vma) 0,
3951 htab->sgot->contents + htab->tlsdesc_got);
3952
3953 memcpy (htab->splt->contents + htab->tlsdesc_plt,
3954 elf64_x86_64_plt0_entry,
3955 PLT_ENTRY_SIZE);
3956
3957 /* Add offset for pushq GOT+8(%rip), since the
3958 instruction uses 6 bytes subtract this value. */
3959 bfd_put_32 (output_bfd,
3960 (htab->sgotplt->output_section->vma
3961 + htab->sgotplt->output_offset
3962 + 8
3963 - htab->splt->output_section->vma
3964 - htab->splt->output_offset
3965 - htab->tlsdesc_plt
3966 - 6),
3967 htab->splt->contents + htab->tlsdesc_plt + 2);
3968 /* Add offset for jmp *GOT+TDG(%rip), where TGD stands for
3969 htab->tlsdesc_got. The 12 is the offset to the end of
3970 the instruction. */
3971 bfd_put_32 (output_bfd,
3972 (htab->sgot->output_section->vma
3973 + htab->sgot->output_offset
3974 + htab->tlsdesc_got
3975 - htab->splt->output_section->vma
3976 - htab->splt->output_offset
3977 - htab->tlsdesc_plt
3978 - 12),
3979 htab->splt->contents + htab->tlsdesc_plt + 8);
3980 }
3981 }
3982 }
3983
3984 if (htab->sgotplt)
3985 {
3986 /* Fill in the first three entries in the global offset table. */
3987 if (htab->sgotplt->size > 0)
3988 {
3989 /* Set the first entry in the global offset table to the address of
3990 the dynamic section. */
3991 if (sdyn == NULL)
3992 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents);
3993 else
3994 bfd_put_64 (output_bfd,
3995 sdyn->output_section->vma + sdyn->output_offset,
3996 htab->sgotplt->contents);
3997 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
3998 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE);
3999 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE*2);
4000 }
4001
4002 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize =
4003 GOT_ENTRY_SIZE;
4004 }
4005
4006 if (htab->sgot && htab->sgot->size > 0)
4007 elf_section_data (htab->sgot->output_section)->this_hdr.sh_entsize
4008 = GOT_ENTRY_SIZE;
4009
4010 return TRUE;
4011 }
4012
4013 /* Return address for Ith PLT stub in section PLT, for relocation REL
4014 or (bfd_vma) -1 if it should not be included. */
4015
4016 static bfd_vma
4017 elf64_x86_64_plt_sym_val (bfd_vma i, const asection *plt,
4018 const arelent *rel ATTRIBUTE_UNUSED)
4019 {
4020 return plt->vma + (i + 1) * PLT_ENTRY_SIZE;
4021 }
4022
4023 /* Handle an x86-64 specific section when reading an object file. This
4024 is called when elfcode.h finds a section with an unknown type. */
4025
4026 static bfd_boolean
4027 elf64_x86_64_section_from_shdr (bfd *abfd,
4028 Elf_Internal_Shdr *hdr,
4029 const char *name,
4030 int shindex)
4031 {
4032 if (hdr->sh_type != SHT_X86_64_UNWIND)
4033 return FALSE;
4034
4035 if (! _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex))
4036 return FALSE;
4037
4038 return TRUE;
4039 }
4040
4041 /* Hook called by the linker routine which adds symbols from an object
4042 file. We use it to put SHN_X86_64_LCOMMON items in .lbss, instead
4043 of .bss. */
4044
4045 static bfd_boolean
4046 elf64_x86_64_add_symbol_hook (bfd *abfd,
4047 struct bfd_link_info *info,
4048 Elf_Internal_Sym *sym,
4049 const char **namep ATTRIBUTE_UNUSED,
4050 flagword *flagsp ATTRIBUTE_UNUSED,
4051 asection **secp,
4052 bfd_vma *valp)
4053 {
4054 asection *lcomm;
4055
4056 switch (sym->st_shndx)
4057 {
4058 case SHN_X86_64_LCOMMON:
4059 lcomm = bfd_get_section_by_name (abfd, "LARGE_COMMON");
4060 if (lcomm == NULL)
4061 {
4062 lcomm = bfd_make_section_with_flags (abfd,
4063 "LARGE_COMMON",
4064 (SEC_ALLOC
4065 | SEC_IS_COMMON
4066 | SEC_LINKER_CREATED));
4067 if (lcomm == NULL)
4068 return FALSE;
4069 elf_section_flags (lcomm) |= SHF_X86_64_LARGE;
4070 }
4071 *secp = lcomm;
4072 *valp = sym->st_size;
4073 break;
4074 }
4075
4076 if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC)
4077 elf_tdata (info->output_bfd)->has_ifunc_symbols = TRUE;
4078
4079 return TRUE;
4080 }
4081
4082
4083 /* Given a BFD section, try to locate the corresponding ELF section
4084 index. */
4085
4086 static bfd_boolean
4087 elf64_x86_64_elf_section_from_bfd_section (bfd *abfd ATTRIBUTE_UNUSED,
4088 asection *sec, int *index)
4089 {
4090 if (sec == &_bfd_elf_large_com_section)
4091 {
4092 *index = SHN_X86_64_LCOMMON;
4093 return TRUE;
4094 }
4095 return FALSE;
4096 }
4097
4098 /* Process a symbol. */
4099
4100 static void
4101 elf64_x86_64_symbol_processing (bfd *abfd ATTRIBUTE_UNUSED,
4102 asymbol *asym)
4103 {
4104 elf_symbol_type *elfsym = (elf_symbol_type *) asym;
4105
4106 switch (elfsym->internal_elf_sym.st_shndx)
4107 {
4108 case SHN_X86_64_LCOMMON:
4109 asym->section = &_bfd_elf_large_com_section;
4110 asym->value = elfsym->internal_elf_sym.st_size;
4111 /* Common symbol doesn't set BSF_GLOBAL. */
4112 asym->flags &= ~BSF_GLOBAL;
4113 break;
4114 }
4115 }
4116
4117 static bfd_boolean
4118 elf64_x86_64_common_definition (Elf_Internal_Sym *sym)
4119 {
4120 return (sym->st_shndx == SHN_COMMON
4121 || sym->st_shndx == SHN_X86_64_LCOMMON);
4122 }
4123
4124 static unsigned int
4125 elf64_x86_64_common_section_index (asection *sec)
4126 {
4127 if ((elf_section_flags (sec) & SHF_X86_64_LARGE) == 0)
4128 return SHN_COMMON;
4129 else
4130 return SHN_X86_64_LCOMMON;
4131 }
4132
4133 static asection *
4134 elf64_x86_64_common_section (asection *sec)
4135 {
4136 if ((elf_section_flags (sec) & SHF_X86_64_LARGE) == 0)
4137 return bfd_com_section_ptr;
4138 else
4139 return &_bfd_elf_large_com_section;
4140 }
4141
4142 static bfd_boolean
4143 elf64_x86_64_merge_symbol (struct bfd_link_info *info ATTRIBUTE_UNUSED,
4144 struct elf_link_hash_entry **sym_hash ATTRIBUTE_UNUSED,
4145 struct elf_link_hash_entry *h,
4146 Elf_Internal_Sym *sym,
4147 asection **psec,
4148 bfd_vma *pvalue ATTRIBUTE_UNUSED,
4149 unsigned int *pold_alignment ATTRIBUTE_UNUSED,
4150 bfd_boolean *skip ATTRIBUTE_UNUSED,
4151 bfd_boolean *override ATTRIBUTE_UNUSED,
4152 bfd_boolean *type_change_ok ATTRIBUTE_UNUSED,
4153 bfd_boolean *size_change_ok ATTRIBUTE_UNUSED,
4154 bfd_boolean *newdef ATTRIBUTE_UNUSED,
4155 bfd_boolean *newdyn,
4156 bfd_boolean *newdyncommon ATTRIBUTE_UNUSED,
4157 bfd_boolean *newweak ATTRIBUTE_UNUSED,
4158 bfd *abfd ATTRIBUTE_UNUSED,
4159 asection **sec,
4160 bfd_boolean *olddef ATTRIBUTE_UNUSED,
4161 bfd_boolean *olddyn,
4162 bfd_boolean *olddyncommon ATTRIBUTE_UNUSED,
4163 bfd_boolean *oldweak ATTRIBUTE_UNUSED,
4164 bfd *oldbfd,
4165 asection **oldsec)
4166 {
4167 /* A normal common symbol and a large common symbol result in a
4168 normal common symbol. We turn the large common symbol into a
4169 normal one. */
4170 if (!*olddyn
4171 && h->root.type == bfd_link_hash_common
4172 && !*newdyn
4173 && bfd_is_com_section (*sec)
4174 && *oldsec != *sec)
4175 {
4176 if (sym->st_shndx == SHN_COMMON
4177 && (elf_section_flags (*oldsec) & SHF_X86_64_LARGE) != 0)
4178 {
4179 h->root.u.c.p->section
4180 = bfd_make_section_old_way (oldbfd, "COMMON");
4181 h->root.u.c.p->section->flags = SEC_ALLOC;
4182 }
4183 else if (sym->st_shndx == SHN_X86_64_LCOMMON
4184 && (elf_section_flags (*oldsec) & SHF_X86_64_LARGE) == 0)
4185 *psec = *sec = bfd_com_section_ptr;
4186 }
4187
4188 return TRUE;
4189 }
4190
4191 static int
4192 elf64_x86_64_additional_program_headers (bfd *abfd,
4193 struct bfd_link_info *info ATTRIBUTE_UNUSED)
4194 {
4195 asection *s;
4196 int count = 0;
4197
4198 /* Check to see if we need a large readonly segment. */
4199 s = bfd_get_section_by_name (abfd, ".lrodata");
4200 if (s && (s->flags & SEC_LOAD))
4201 count++;
4202
4203 /* Check to see if we need a large data segment. Since .lbss sections
4204 is placed right after the .bss section, there should be no need for
4205 a large data segment just because of .lbss. */
4206 s = bfd_get_section_by_name (abfd, ".ldata");
4207 if (s && (s->flags & SEC_LOAD))
4208 count++;
4209
4210 return count;
4211 }
4212
4213 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
4214
4215 static bfd_boolean
4216 elf64_x86_64_hash_symbol (struct elf_link_hash_entry *h)
4217 {
4218 if (h->plt.offset != (bfd_vma) -1
4219 && !h->def_regular
4220 && !h->pointer_equality_needed)
4221 return FALSE;
4222
4223 return _bfd_elf_hash_symbol (h);
4224 }
4225
4226 static const struct bfd_elf_special_section
4227 elf64_x86_64_special_sections[]=
4228 {
4229 { STRING_COMMA_LEN (".gnu.linkonce.lb"), -2, SHT_NOBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE},
4230 { STRING_COMMA_LEN (".gnu.linkonce.lr"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_X86_64_LARGE},
4231 { STRING_COMMA_LEN (".gnu.linkonce.lt"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_EXECINSTR + SHF_X86_64_LARGE},
4232 { STRING_COMMA_LEN (".lbss"), -2, SHT_NOBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE},
4233 { STRING_COMMA_LEN (".ldata"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE},
4234 { STRING_COMMA_LEN (".lrodata"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_X86_64_LARGE},
4235 { NULL, 0, 0, 0, 0 }
4236 };
4237
4238 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
4239 #define TARGET_LITTLE_NAME "elf64-x86-64"
4240 #define ELF_ARCH bfd_arch_i386
4241 #define ELF_MACHINE_CODE EM_X86_64
4242 #define ELF_MAXPAGESIZE 0x200000
4243 #define ELF_MINPAGESIZE 0x1000
4244 #define ELF_COMMONPAGESIZE 0x1000
4245
4246 #define elf_backend_can_gc_sections 1
4247 #define elf_backend_can_refcount 1
4248 #define elf_backend_want_got_plt 1
4249 #define elf_backend_plt_readonly 1
4250 #define elf_backend_want_plt_sym 0
4251 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
4252 #define elf_backend_rela_normal 1
4253
4254 #define elf_info_to_howto elf64_x86_64_info_to_howto
4255
4256 #define bfd_elf64_bfd_link_hash_table_create \
4257 elf64_x86_64_link_hash_table_create
4258 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
4259 #define bfd_elf64_bfd_reloc_name_lookup \
4260 elf64_x86_64_reloc_name_lookup
4261
4262 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
4263 #define elf_backend_relocs_compatible _bfd_elf_relocs_compatible
4264 #define elf_backend_check_relocs elf64_x86_64_check_relocs
4265 #define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol
4266 #define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections
4267 #define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections
4268 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
4269 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
4270 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
4271 #define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus
4272 #define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo
4273 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
4274 #define elf_backend_relocate_section elf64_x86_64_relocate_section
4275 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
4276 #define elf_backend_always_size_sections elf64_x86_64_always_size_sections
4277 #define elf_backend_init_index_section _bfd_elf_init_1_index_section
4278 #define elf_backend_plt_sym_val elf64_x86_64_plt_sym_val
4279 #define elf_backend_object_p elf64_x86_64_elf_object_p
4280 #define bfd_elf64_mkobject elf64_x86_64_mkobject
4281
4282 #define elf_backend_section_from_shdr \
4283 elf64_x86_64_section_from_shdr
4284
4285 #define elf_backend_section_from_bfd_section \
4286 elf64_x86_64_elf_section_from_bfd_section
4287 #define elf_backend_add_symbol_hook \
4288 elf64_x86_64_add_symbol_hook
4289 #define elf_backend_symbol_processing \
4290 elf64_x86_64_symbol_processing
4291 #define elf_backend_common_section_index \
4292 elf64_x86_64_common_section_index
4293 #define elf_backend_common_section \
4294 elf64_x86_64_common_section
4295 #define elf_backend_common_definition \
4296 elf64_x86_64_common_definition
4297 #define elf_backend_merge_symbol \
4298 elf64_x86_64_merge_symbol
4299 #define elf_backend_special_sections \
4300 elf64_x86_64_special_sections
4301 #define elf_backend_additional_program_headers \
4302 elf64_x86_64_additional_program_headers
4303 #define elf_backend_hash_symbol \
4304 elf64_x86_64_hash_symbol
4305
4306 #undef elf_backend_post_process_headers
4307 #define elf_backend_post_process_headers _bfd_elf_set_osabi
4308
4309 #include "elf64-target.h"
4310
4311 /* FreeBSD support. */
4312
4313 #undef TARGET_LITTLE_SYM
4314 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_freebsd_vec
4315 #undef TARGET_LITTLE_NAME
4316 #define TARGET_LITTLE_NAME "elf64-x86-64-freebsd"
4317
4318 #undef ELF_OSABI
4319 #define ELF_OSABI ELFOSABI_FREEBSD
4320
4321 #undef elf64_bed
4322 #define elf64_bed elf64_x86_64_fbsd_bed
4323
4324 #include "elf64-target.h"
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