* configure.tgt (i[3-7]86-*-solaris2*, i[3-7]86-*-solaris*): Correct
[binutils.git] / bfd / elf64-x86-64.c
blob6ca622a0d23d26df5c30b92ade0c28639a0277b8
1 /* X86-64 specific support for 64-bit ELF
2 Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006
3 Free Software Foundation, Inc.
4 Contributed by Jan Hubicka <jh@suse.cz>.
6 This file is part of BFD, the Binary File Descriptor library.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
22 #include "bfd.h"
23 #include "sysdep.h"
24 #include "bfdlink.h"
25 #include "libbfd.h"
26 #include "elf-bfd.h"
28 #include "elf/x86-64.h"
30 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
31 #define MINUS_ONE (~ (bfd_vma) 0)
33 /* The relocation "howto" table. Order of fields:
34 type, rightshift, size, bitsize, pc_relative, bitpos, complain_on_overflow,
35 special_function, name, partial_inplace, src_mask, dst_mask, pcrel_offset. */
36 static reloc_howto_type x86_64_elf_howto_table[] =
38 HOWTO(R_X86_64_NONE, 0, 0, 0, FALSE, 0, complain_overflow_dont,
39 bfd_elf_generic_reloc, "R_X86_64_NONE", FALSE, 0x00000000, 0x00000000,
40 FALSE),
41 HOWTO(R_X86_64_64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
42 bfd_elf_generic_reloc, "R_X86_64_64", FALSE, MINUS_ONE, MINUS_ONE,
43 FALSE),
44 HOWTO(R_X86_64_PC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
45 bfd_elf_generic_reloc, "R_X86_64_PC32", FALSE, 0xffffffff, 0xffffffff,
46 TRUE),
47 HOWTO(R_X86_64_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
48 bfd_elf_generic_reloc, "R_X86_64_GOT32", FALSE, 0xffffffff, 0xffffffff,
49 FALSE),
50 HOWTO(R_X86_64_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
51 bfd_elf_generic_reloc, "R_X86_64_PLT32", FALSE, 0xffffffff, 0xffffffff,
52 TRUE),
53 HOWTO(R_X86_64_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
54 bfd_elf_generic_reloc, "R_X86_64_COPY", FALSE, 0xffffffff, 0xffffffff,
55 FALSE),
56 HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
57 bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", FALSE, MINUS_ONE,
58 MINUS_ONE, FALSE),
59 HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
60 bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", FALSE, MINUS_ONE,
61 MINUS_ONE, FALSE),
62 HOWTO(R_X86_64_RELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
63 bfd_elf_generic_reloc, "R_X86_64_RELATIVE", FALSE, MINUS_ONE,
64 MINUS_ONE, FALSE),
65 HOWTO(R_X86_64_GOTPCREL, 0, 2, 32, TRUE, 0, complain_overflow_signed,
66 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", FALSE, 0xffffffff,
67 0xffffffff, TRUE),
68 HOWTO(R_X86_64_32, 0, 2, 32, FALSE, 0, complain_overflow_unsigned,
69 bfd_elf_generic_reloc, "R_X86_64_32", FALSE, 0xffffffff, 0xffffffff,
70 FALSE),
71 HOWTO(R_X86_64_32S, 0, 2, 32, FALSE, 0, complain_overflow_signed,
72 bfd_elf_generic_reloc, "R_X86_64_32S", FALSE, 0xffffffff, 0xffffffff,
73 FALSE),
74 HOWTO(R_X86_64_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
75 bfd_elf_generic_reloc, "R_X86_64_16", FALSE, 0xffff, 0xffff, FALSE),
76 HOWTO(R_X86_64_PC16,0, 1, 16, TRUE, 0, complain_overflow_bitfield,
77 bfd_elf_generic_reloc, "R_X86_64_PC16", FALSE, 0xffff, 0xffff, TRUE),
78 HOWTO(R_X86_64_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,
79 bfd_elf_generic_reloc, "R_X86_64_8", FALSE, 0xff, 0xff, FALSE),
80 HOWTO(R_X86_64_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed,
81 bfd_elf_generic_reloc, "R_X86_64_PC8", FALSE, 0xff, 0xff, TRUE),
82 HOWTO(R_X86_64_DTPMOD64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
83 bfd_elf_generic_reloc, "R_X86_64_DTPMOD64", FALSE, MINUS_ONE,
84 MINUS_ONE, FALSE),
85 HOWTO(R_X86_64_DTPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
86 bfd_elf_generic_reloc, "R_X86_64_DTPOFF64", FALSE, MINUS_ONE,
87 MINUS_ONE, FALSE),
88 HOWTO(R_X86_64_TPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
89 bfd_elf_generic_reloc, "R_X86_64_TPOFF64", FALSE, MINUS_ONE,
90 MINUS_ONE, FALSE),
91 HOWTO(R_X86_64_TLSGD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
92 bfd_elf_generic_reloc, "R_X86_64_TLSGD", FALSE, 0xffffffff,
93 0xffffffff, TRUE),
94 HOWTO(R_X86_64_TLSLD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
95 bfd_elf_generic_reloc, "R_X86_64_TLSLD", FALSE, 0xffffffff,
96 0xffffffff, TRUE),
97 HOWTO(R_X86_64_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
98 bfd_elf_generic_reloc, "R_X86_64_DTPOFF32", FALSE, 0xffffffff,
99 0xffffffff, FALSE),
100 HOWTO(R_X86_64_GOTTPOFF, 0, 2, 32, TRUE, 0, complain_overflow_signed,
101 bfd_elf_generic_reloc, "R_X86_64_GOTTPOFF", FALSE, 0xffffffff,
102 0xffffffff, TRUE),
103 HOWTO(R_X86_64_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
104 bfd_elf_generic_reloc, "R_X86_64_TPOFF32", FALSE, 0xffffffff,
105 0xffffffff, FALSE),
106 HOWTO(R_X86_64_PC64, 0, 4, 64, TRUE, 0, complain_overflow_bitfield,
107 bfd_elf_generic_reloc, "R_X86_64_PC64", FALSE, MINUS_ONE, MINUS_ONE,
108 TRUE),
109 HOWTO(R_X86_64_GOTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
110 bfd_elf_generic_reloc, "R_X86_64_GOTOFF64",
111 FALSE, MINUS_ONE, MINUS_ONE, FALSE),
112 HOWTO(R_X86_64_GOTPC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
113 bfd_elf_generic_reloc, "R_X86_64_GOTPC32",
114 FALSE, 0xffffffff, 0xffffffff, TRUE),
115 HOWTO(R_X86_64_GOT64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
116 bfd_elf_generic_reloc, "R_X86_64_GOT64", FALSE, MINUS_ONE, MINUS_ONE,
117 FALSE),
118 HOWTO(R_X86_64_GOTPCREL64, 0, 4, 64, TRUE, 0, complain_overflow_signed,
119 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL64", FALSE, MINUS_ONE,
120 MINUS_ONE, TRUE),
121 HOWTO(R_X86_64_GOTPC64, 0, 4, 64, TRUE, 0, complain_overflow_signed,
122 bfd_elf_generic_reloc, "R_X86_64_GOTPC64",
123 FALSE, MINUS_ONE, MINUS_ONE, TRUE),
124 HOWTO(R_X86_64_GOTPLT64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
125 bfd_elf_generic_reloc, "R_X86_64_GOTPLT64", FALSE, MINUS_ONE,
126 MINUS_ONE, FALSE),
127 HOWTO(R_X86_64_PLTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
128 bfd_elf_generic_reloc, "R_X86_64_PLTOFF64", FALSE, MINUS_ONE,
129 MINUS_ONE, FALSE),
130 EMPTY_HOWTO (32),
131 EMPTY_HOWTO (33),
132 HOWTO(R_X86_64_GOTPC32_TLSDESC, 0, 2, 32, TRUE, 0,
133 complain_overflow_bitfield, bfd_elf_generic_reloc,
134 "R_X86_64_GOTPC32_TLSDESC",
135 FALSE, 0xffffffff, 0xffffffff, TRUE),
136 HOWTO(R_X86_64_TLSDESC_CALL, 0, 0, 0, FALSE, 0,
137 complain_overflow_dont, bfd_elf_generic_reloc,
138 "R_X86_64_TLSDESC_CALL",
139 FALSE, 0, 0, FALSE),
140 HOWTO(R_X86_64_TLSDESC, 0, 4, 64, FALSE, 0,
141 complain_overflow_bitfield, bfd_elf_generic_reloc,
142 "R_X86_64_TLSDESC",
143 FALSE, MINUS_ONE, MINUS_ONE, FALSE),
145 /* We have a gap in the reloc numbers here.
146 R_X86_64_standard counts the number up to this point, and
147 R_X86_64_vt_offset is the value to subtract from a reloc type of
148 R_X86_64_GNU_VT* to form an index into this table. */
149 #define R_X86_64_standard (R_X86_64_TLSDESC + 1)
150 #define R_X86_64_vt_offset (R_X86_64_GNU_VTINHERIT - R_X86_64_standard)
152 /* GNU extension to record C++ vtable hierarchy. */
153 HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, FALSE, 0, complain_overflow_dont,
154 NULL, "R_X86_64_GNU_VTINHERIT", FALSE, 0, 0, FALSE),
156 /* GNU extension to record C++ vtable member usage. */
157 HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, FALSE, 0, complain_overflow_dont,
158 _bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", FALSE, 0, 0,
159 FALSE)
162 /* Map BFD relocs to the x86_64 elf relocs. */
163 struct elf_reloc_map
165 bfd_reloc_code_real_type bfd_reloc_val;
166 unsigned char elf_reloc_val;
169 static const struct elf_reloc_map x86_64_reloc_map[] =
171 { BFD_RELOC_NONE, R_X86_64_NONE, },
172 { BFD_RELOC_64, R_X86_64_64, },
173 { BFD_RELOC_32_PCREL, R_X86_64_PC32, },
174 { BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,},
175 { BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,},
176 { BFD_RELOC_X86_64_COPY, R_X86_64_COPY, },
177 { BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, },
178 { BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, },
179 { BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, },
180 { BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, },
181 { BFD_RELOC_32, R_X86_64_32, },
182 { BFD_RELOC_X86_64_32S, R_X86_64_32S, },
183 { BFD_RELOC_16, R_X86_64_16, },
184 { BFD_RELOC_16_PCREL, R_X86_64_PC16, },
185 { BFD_RELOC_8, R_X86_64_8, },
186 { BFD_RELOC_8_PCREL, R_X86_64_PC8, },
187 { BFD_RELOC_X86_64_DTPMOD64, R_X86_64_DTPMOD64, },
188 { BFD_RELOC_X86_64_DTPOFF64, R_X86_64_DTPOFF64, },
189 { BFD_RELOC_X86_64_TPOFF64, R_X86_64_TPOFF64, },
190 { BFD_RELOC_X86_64_TLSGD, R_X86_64_TLSGD, },
191 { BFD_RELOC_X86_64_TLSLD, R_X86_64_TLSLD, },
192 { BFD_RELOC_X86_64_DTPOFF32, R_X86_64_DTPOFF32, },
193 { BFD_RELOC_X86_64_GOTTPOFF, R_X86_64_GOTTPOFF, },
194 { BFD_RELOC_X86_64_TPOFF32, R_X86_64_TPOFF32, },
195 { BFD_RELOC_64_PCREL, R_X86_64_PC64, },
196 { BFD_RELOC_X86_64_GOTOFF64, R_X86_64_GOTOFF64, },
197 { BFD_RELOC_X86_64_GOTPC32, R_X86_64_GOTPC32, },
198 { BFD_RELOC_X86_64_GOT64, R_X86_64_GOT64, },
199 { BFD_RELOC_X86_64_GOTPCREL64,R_X86_64_GOTPCREL64, },
200 { BFD_RELOC_X86_64_GOTPC64, R_X86_64_GOTPC64, },
201 { BFD_RELOC_X86_64_GOTPLT64, R_X86_64_GOTPLT64, },
202 { BFD_RELOC_X86_64_PLTOFF64, R_X86_64_PLTOFF64, },
203 { BFD_RELOC_X86_64_GOTPC32_TLSDESC, R_X86_64_GOTPC32_TLSDESC, },
204 { BFD_RELOC_X86_64_TLSDESC_CALL, R_X86_64_TLSDESC_CALL, },
205 { BFD_RELOC_X86_64_TLSDESC, R_X86_64_TLSDESC, },
206 { BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
207 { BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
210 static reloc_howto_type *
211 elf64_x86_64_rtype_to_howto (bfd *abfd, unsigned r_type)
213 unsigned i;
215 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT
216 || r_type >= (unsigned int) R_X86_64_max)
218 if (r_type >= (unsigned int) R_X86_64_standard)
220 (*_bfd_error_handler) (_("%B: invalid relocation type %d"),
221 abfd, (int) r_type);
222 r_type = R_X86_64_NONE;
224 i = r_type;
226 else
227 i = r_type - (unsigned int) R_X86_64_vt_offset;
228 BFD_ASSERT (x86_64_elf_howto_table[i].type == r_type);
229 return &x86_64_elf_howto_table[i];
232 /* Given a BFD reloc type, return a HOWTO structure. */
233 static reloc_howto_type *
234 elf64_x86_64_reloc_type_lookup (bfd *abfd,
235 bfd_reloc_code_real_type code)
237 unsigned int i;
239 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
240 i++)
242 if (x86_64_reloc_map[i].bfd_reloc_val == code)
243 return elf64_x86_64_rtype_to_howto (abfd,
244 x86_64_reloc_map[i].elf_reloc_val);
246 return 0;
249 /* Given an x86_64 ELF reloc type, fill in an arelent structure. */
251 static void
252 elf64_x86_64_info_to_howto (bfd *abfd ATTRIBUTE_UNUSED, arelent *cache_ptr,
253 Elf_Internal_Rela *dst)
255 unsigned r_type;
257 r_type = ELF64_R_TYPE (dst->r_info);
258 cache_ptr->howto = elf64_x86_64_rtype_to_howto (abfd, r_type);
259 BFD_ASSERT (r_type == cache_ptr->howto->type);
262 /* Support for core dump NOTE sections. */
263 static bfd_boolean
264 elf64_x86_64_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
266 int offset;
267 size_t size;
269 switch (note->descsz)
271 default:
272 return FALSE;
274 case 336: /* sizeof(istruct elf_prstatus) on Linux/x86_64 */
275 /* pr_cursig */
276 elf_tdata (abfd)->core_signal
277 = bfd_get_16 (abfd, note->descdata + 12);
279 /* pr_pid */
280 elf_tdata (abfd)->core_pid
281 = bfd_get_32 (abfd, note->descdata + 32);
283 /* pr_reg */
284 offset = 112;
285 size = 216;
287 break;
290 /* Make a ".reg/999" section. */
291 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
292 size, note->descpos + offset);
295 static bfd_boolean
296 elf64_x86_64_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
298 switch (note->descsz)
300 default:
301 return FALSE;
303 case 136: /* sizeof(struct elf_prpsinfo) on Linux/x86_64 */
304 elf_tdata (abfd)->core_program
305 = _bfd_elfcore_strndup (abfd, note->descdata + 40, 16);
306 elf_tdata (abfd)->core_command
307 = _bfd_elfcore_strndup (abfd, note->descdata + 56, 80);
310 /* Note that for some reason, a spurious space is tacked
311 onto the end of the args in some (at least one anyway)
312 implementations, so strip it off if it exists. */
315 char *command = elf_tdata (abfd)->core_command;
316 int n = strlen (command);
318 if (0 < n && command[n - 1] == ' ')
319 command[n - 1] = '\0';
322 return TRUE;
325 /* Functions for the x86-64 ELF linker. */
327 /* The name of the dynamic interpreter. This is put in the .interp
328 section. */
330 #define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
332 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
333 copying dynamic variables from a shared lib into an app's dynbss
334 section, and instead use a dynamic relocation to point into the
335 shared lib. */
336 #define ELIMINATE_COPY_RELOCS 1
338 /* The size in bytes of an entry in the global offset table. */
340 #define GOT_ENTRY_SIZE 8
342 /* The size in bytes of an entry in the procedure linkage table. */
344 #define PLT_ENTRY_SIZE 16
346 /* The first entry in a procedure linkage table looks like this. See the
347 SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
349 static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
351 0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
352 0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
353 0x0f, 0x1f, 0x40, 0x00 /* nopl 0(%rax) */
356 /* Subsequent entries in a procedure linkage table look like this. */
358 static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
360 0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
361 0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
362 0x68, /* pushq immediate */
363 0, 0, 0, 0, /* replaced with index into relocation table. */
364 0xe9, /* jmp relative */
365 0, 0, 0, 0 /* replaced with offset to start of .plt0. */
368 /* The x86-64 linker needs to keep track of the number of relocs that
369 it decides to copy as dynamic relocs in check_relocs for each symbol.
370 This is so that it can later discard them if they are found to be
371 unnecessary. We store the information in a field extending the
372 regular ELF linker hash table. */
374 struct elf64_x86_64_dyn_relocs
376 /* Next section. */
377 struct elf64_x86_64_dyn_relocs *next;
379 /* The input section of the reloc. */
380 asection *sec;
382 /* Total number of relocs copied for the input section. */
383 bfd_size_type count;
385 /* Number of pc-relative relocs copied for the input section. */
386 bfd_size_type pc_count;
389 /* x86-64 ELF linker hash entry. */
391 struct elf64_x86_64_link_hash_entry
393 struct elf_link_hash_entry elf;
395 /* Track dynamic relocs copied for this symbol. */
396 struct elf64_x86_64_dyn_relocs *dyn_relocs;
398 #define GOT_UNKNOWN 0
399 #define GOT_NORMAL 1
400 #define GOT_TLS_GD 2
401 #define GOT_TLS_IE 3
402 #define GOT_TLS_GDESC 4
403 #define GOT_TLS_GD_BOTH_P(type) \
404 ((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
405 #define GOT_TLS_GD_P(type) \
406 ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
407 #define GOT_TLS_GDESC_P(type) \
408 ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
409 #define GOT_TLS_GD_ANY_P(type) \
410 (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
411 unsigned char tls_type;
413 /* Offset of the GOTPLT entry reserved for the TLS descriptor,
414 starting at the end of the jump table. */
415 bfd_vma tlsdesc_got;
418 #define elf64_x86_64_hash_entry(ent) \
419 ((struct elf64_x86_64_link_hash_entry *)(ent))
421 struct elf64_x86_64_obj_tdata
423 struct elf_obj_tdata root;
425 /* tls_type for each local got entry. */
426 char *local_got_tls_type;
428 /* GOTPLT entries for TLS descriptors. */
429 bfd_vma *local_tlsdesc_gotent;
432 #define elf64_x86_64_tdata(abfd) \
433 ((struct elf64_x86_64_obj_tdata *) (abfd)->tdata.any)
435 #define elf64_x86_64_local_got_tls_type(abfd) \
436 (elf64_x86_64_tdata (abfd)->local_got_tls_type)
438 #define elf64_x86_64_local_tlsdesc_gotent(abfd) \
439 (elf64_x86_64_tdata (abfd)->local_tlsdesc_gotent)
441 /* x86-64 ELF linker hash table. */
443 struct elf64_x86_64_link_hash_table
445 struct elf_link_hash_table elf;
447 /* Short-cuts to get to dynamic linker sections. */
448 asection *sgot;
449 asection *sgotplt;
450 asection *srelgot;
451 asection *splt;
452 asection *srelplt;
453 asection *sdynbss;
454 asection *srelbss;
456 /* The offset into splt of the PLT entry for the TLS descriptor
457 resolver. Special values are 0, if not necessary (or not found
458 to be necessary yet), and -1 if needed but not determined
459 yet. */
460 bfd_vma tlsdesc_plt;
461 /* The offset into sgot of the GOT entry used by the PLT entry
462 above. */
463 bfd_vma tlsdesc_got;
465 union {
466 bfd_signed_vma refcount;
467 bfd_vma offset;
468 } tls_ld_got;
470 /* The amount of space used by the jump slots in the GOT. */
471 bfd_vma sgotplt_jump_table_size;
473 /* Small local sym to section mapping cache. */
474 struct sym_sec_cache sym_sec;
477 /* Get the x86-64 ELF linker hash table from a link_info structure. */
479 #define elf64_x86_64_hash_table(p) \
480 ((struct elf64_x86_64_link_hash_table *) ((p)->hash))
482 #define elf64_x86_64_compute_jump_table_size(htab) \
483 ((htab)->srelplt->reloc_count * GOT_ENTRY_SIZE)
485 /* Create an entry in an x86-64 ELF linker hash table. */
487 static struct bfd_hash_entry *
488 link_hash_newfunc (struct bfd_hash_entry *entry, struct bfd_hash_table *table,
489 const char *string)
491 /* Allocate the structure if it has not already been allocated by a
492 subclass. */
493 if (entry == NULL)
495 entry = bfd_hash_allocate (table,
496 sizeof (struct elf64_x86_64_link_hash_entry));
497 if (entry == NULL)
498 return entry;
501 /* Call the allocation method of the superclass. */
502 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
503 if (entry != NULL)
505 struct elf64_x86_64_link_hash_entry *eh;
507 eh = (struct elf64_x86_64_link_hash_entry *) entry;
508 eh->dyn_relocs = NULL;
509 eh->tls_type = GOT_UNKNOWN;
510 eh->tlsdesc_got = (bfd_vma) -1;
513 return entry;
516 /* Create an X86-64 ELF linker hash table. */
518 static struct bfd_link_hash_table *
519 elf64_x86_64_link_hash_table_create (bfd *abfd)
521 struct elf64_x86_64_link_hash_table *ret;
522 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table);
524 ret = (struct elf64_x86_64_link_hash_table *) bfd_malloc (amt);
525 if (ret == NULL)
526 return NULL;
528 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc,
529 sizeof (struct elf64_x86_64_link_hash_entry)))
531 free (ret);
532 return NULL;
535 ret->sgot = NULL;
536 ret->sgotplt = NULL;
537 ret->srelgot = NULL;
538 ret->splt = NULL;
539 ret->srelplt = NULL;
540 ret->sdynbss = NULL;
541 ret->srelbss = NULL;
542 ret->sym_sec.abfd = NULL;
543 ret->tlsdesc_plt = 0;
544 ret->tlsdesc_got = 0;
545 ret->tls_ld_got.refcount = 0;
546 ret->sgotplt_jump_table_size = 0;
548 return &ret->elf.root;
551 /* Create .got, .gotplt, and .rela.got sections in DYNOBJ, and set up
552 shortcuts to them in our hash table. */
554 static bfd_boolean
555 create_got_section (bfd *dynobj, struct bfd_link_info *info)
557 struct elf64_x86_64_link_hash_table *htab;
559 if (! _bfd_elf_create_got_section (dynobj, info))
560 return FALSE;
562 htab = elf64_x86_64_hash_table (info);
563 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
564 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
565 if (!htab->sgot || !htab->sgotplt)
566 abort ();
568 htab->srelgot = bfd_make_section_with_flags (dynobj, ".rela.got",
569 (SEC_ALLOC | SEC_LOAD
570 | SEC_HAS_CONTENTS
571 | SEC_IN_MEMORY
572 | SEC_LINKER_CREATED
573 | SEC_READONLY));
574 if (htab->srelgot == NULL
575 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 3))
576 return FALSE;
577 return TRUE;
580 /* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and
581 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our
582 hash table. */
584 static bfd_boolean
585 elf64_x86_64_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info)
587 struct elf64_x86_64_link_hash_table *htab;
589 htab = elf64_x86_64_hash_table (info);
590 if (!htab->sgot && !create_got_section (dynobj, info))
591 return FALSE;
593 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
594 return FALSE;
596 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
597 htab->srelplt = bfd_get_section_by_name (dynobj, ".rela.plt");
598 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
599 if (!info->shared)
600 htab->srelbss = bfd_get_section_by_name (dynobj, ".rela.bss");
602 if (!htab->splt || !htab->srelplt || !htab->sdynbss
603 || (!info->shared && !htab->srelbss))
604 abort ();
606 return TRUE;
609 /* Copy the extra info we tack onto an elf_link_hash_entry. */
611 static void
612 elf64_x86_64_copy_indirect_symbol (struct bfd_link_info *info,
613 struct elf_link_hash_entry *dir,
614 struct elf_link_hash_entry *ind)
616 struct elf64_x86_64_link_hash_entry *edir, *eind;
618 edir = (struct elf64_x86_64_link_hash_entry *) dir;
619 eind = (struct elf64_x86_64_link_hash_entry *) ind;
621 if (eind->dyn_relocs != NULL)
623 if (edir->dyn_relocs != NULL)
625 struct elf64_x86_64_dyn_relocs **pp;
626 struct elf64_x86_64_dyn_relocs *p;
628 /* Add reloc counts against the indirect sym to the direct sym
629 list. Merge any entries against the same section. */
630 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
632 struct elf64_x86_64_dyn_relocs *q;
634 for (q = edir->dyn_relocs; q != NULL; q = q->next)
635 if (q->sec == p->sec)
637 q->pc_count += p->pc_count;
638 q->count += p->count;
639 *pp = p->next;
640 break;
642 if (q == NULL)
643 pp = &p->next;
645 *pp = edir->dyn_relocs;
648 edir->dyn_relocs = eind->dyn_relocs;
649 eind->dyn_relocs = NULL;
652 if (ind->root.type == bfd_link_hash_indirect
653 && dir->got.refcount <= 0)
655 edir->tls_type = eind->tls_type;
656 eind->tls_type = GOT_UNKNOWN;
659 if (ELIMINATE_COPY_RELOCS
660 && ind->root.type != bfd_link_hash_indirect
661 && dir->dynamic_adjusted)
663 /* If called to transfer flags for a weakdef during processing
664 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
665 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
666 dir->ref_dynamic |= ind->ref_dynamic;
667 dir->ref_regular |= ind->ref_regular;
668 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
669 dir->needs_plt |= ind->needs_plt;
670 dir->pointer_equality_needed |= ind->pointer_equality_needed;
672 else
673 _bfd_elf_link_hash_copy_indirect (info, dir, ind);
676 static bfd_boolean
677 elf64_x86_64_mkobject (bfd *abfd)
679 if (abfd->tdata.any == NULL)
681 bfd_size_type amt = sizeof (struct elf64_x86_64_obj_tdata);
682 abfd->tdata.any = bfd_zalloc (abfd, amt);
683 if (abfd->tdata.any == NULL)
684 return FALSE;
686 return bfd_elf_mkobject (abfd);
689 static bfd_boolean
690 elf64_x86_64_elf_object_p (bfd *abfd)
692 /* Set the right machine number for an x86-64 elf64 file. */
693 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
694 return TRUE;
697 static int
698 elf64_x86_64_tls_transition (struct bfd_link_info *info, int r_type, int is_local)
700 if (info->shared)
701 return r_type;
703 switch (r_type)
705 case R_X86_64_TLSGD:
706 case R_X86_64_GOTPC32_TLSDESC:
707 case R_X86_64_TLSDESC_CALL:
708 case R_X86_64_GOTTPOFF:
709 if (is_local)
710 return R_X86_64_TPOFF32;
711 return R_X86_64_GOTTPOFF;
712 case R_X86_64_TLSLD:
713 return R_X86_64_TPOFF32;
716 return r_type;
719 /* Look through the relocs for a section during the first phase, and
720 calculate needed space in the global offset table, procedure
721 linkage table, and dynamic reloc sections. */
723 static bfd_boolean
724 elf64_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info, asection *sec,
725 const Elf_Internal_Rela *relocs)
727 struct elf64_x86_64_link_hash_table *htab;
728 Elf_Internal_Shdr *symtab_hdr;
729 struct elf_link_hash_entry **sym_hashes;
730 const Elf_Internal_Rela *rel;
731 const Elf_Internal_Rela *rel_end;
732 asection *sreloc;
734 if (info->relocatable)
735 return TRUE;
737 htab = elf64_x86_64_hash_table (info);
738 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
739 sym_hashes = elf_sym_hashes (abfd);
741 sreloc = NULL;
743 rel_end = relocs + sec->reloc_count;
744 for (rel = relocs; rel < rel_end; rel++)
746 unsigned int r_type;
747 unsigned long r_symndx;
748 struct elf_link_hash_entry *h;
750 r_symndx = ELF64_R_SYM (rel->r_info);
751 r_type = ELF64_R_TYPE (rel->r_info);
753 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
755 (*_bfd_error_handler) (_("%B: bad symbol index: %d"),
756 abfd, r_symndx);
757 return FALSE;
760 if (r_symndx < symtab_hdr->sh_info)
761 h = NULL;
762 else
764 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
765 while (h->root.type == bfd_link_hash_indirect
766 || h->root.type == bfd_link_hash_warning)
767 h = (struct elf_link_hash_entry *) h->root.u.i.link;
770 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
771 switch (r_type)
773 case R_X86_64_TLSLD:
774 htab->tls_ld_got.refcount += 1;
775 goto create_got;
777 case R_X86_64_TPOFF32:
778 if (info->shared)
780 (*_bfd_error_handler)
781 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
782 abfd,
783 x86_64_elf_howto_table[r_type].name,
784 (h) ? h->root.root.string : "a local symbol");
785 bfd_set_error (bfd_error_bad_value);
786 return FALSE;
788 break;
790 case R_X86_64_GOTTPOFF:
791 if (info->shared)
792 info->flags |= DF_STATIC_TLS;
793 /* Fall through */
795 case R_X86_64_GOT32:
796 case R_X86_64_GOTPCREL:
797 case R_X86_64_TLSGD:
798 case R_X86_64_GOT64:
799 case R_X86_64_GOTPCREL64:
800 case R_X86_64_GOTPLT64:
801 case R_X86_64_GOTPC32_TLSDESC:
802 case R_X86_64_TLSDESC_CALL:
803 /* This symbol requires a global offset table entry. */
805 int tls_type, old_tls_type;
807 switch (r_type)
809 default: tls_type = GOT_NORMAL; break;
810 case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
811 case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
812 case R_X86_64_GOTPC32_TLSDESC:
813 case R_X86_64_TLSDESC_CALL:
814 tls_type = GOT_TLS_GDESC; break;
817 if (h != NULL)
819 if (r_type == R_X86_64_GOTPLT64)
821 /* This relocation indicates that we also need
822 a PLT entry, as this is a function. We don't need
823 a PLT entry for local symbols. */
824 h->needs_plt = 1;
825 h->plt.refcount += 1;
827 h->got.refcount += 1;
828 old_tls_type = elf64_x86_64_hash_entry (h)->tls_type;
830 else
832 bfd_signed_vma *local_got_refcounts;
834 /* This is a global offset table entry for a local symbol. */
835 local_got_refcounts = elf_local_got_refcounts (abfd);
836 if (local_got_refcounts == NULL)
838 bfd_size_type size;
840 size = symtab_hdr->sh_info;
841 size *= sizeof (bfd_signed_vma)
842 + sizeof (bfd_vma) + sizeof (char);
843 local_got_refcounts = ((bfd_signed_vma *)
844 bfd_zalloc (abfd, size));
845 if (local_got_refcounts == NULL)
846 return FALSE;
847 elf_local_got_refcounts (abfd) = local_got_refcounts;
848 elf64_x86_64_local_tlsdesc_gotent (abfd)
849 = (bfd_vma *) (local_got_refcounts + symtab_hdr->sh_info);
850 elf64_x86_64_local_got_tls_type (abfd)
851 = (char *) (local_got_refcounts + 2 * symtab_hdr->sh_info);
853 local_got_refcounts[r_symndx] += 1;
854 old_tls_type
855 = elf64_x86_64_local_got_tls_type (abfd) [r_symndx];
858 /* If a TLS symbol is accessed using IE at least once,
859 there is no point to use dynamic model for it. */
860 if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
861 && (! GOT_TLS_GD_ANY_P (old_tls_type)
862 || tls_type != GOT_TLS_IE))
864 if (old_tls_type == GOT_TLS_IE && GOT_TLS_GD_ANY_P (tls_type))
865 tls_type = old_tls_type;
866 else if (GOT_TLS_GD_ANY_P (old_tls_type)
867 && GOT_TLS_GD_ANY_P (tls_type))
868 tls_type |= old_tls_type;
869 else
871 (*_bfd_error_handler)
872 (_("%B: %s' accessed both as normal and thread local symbol"),
873 abfd, h ? h->root.root.string : "<local>");
874 return FALSE;
878 if (old_tls_type != tls_type)
880 if (h != NULL)
881 elf64_x86_64_hash_entry (h)->tls_type = tls_type;
882 else
883 elf64_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
886 /* Fall through */
888 case R_X86_64_GOTOFF64:
889 case R_X86_64_GOTPC32:
890 case R_X86_64_GOTPC64:
891 create_got:
892 if (htab->sgot == NULL)
894 if (htab->elf.dynobj == NULL)
895 htab->elf.dynobj = abfd;
896 if (!create_got_section (htab->elf.dynobj, info))
897 return FALSE;
899 break;
901 case R_X86_64_PLT32:
902 /* This symbol requires a procedure linkage table entry. We
903 actually build the entry in adjust_dynamic_symbol,
904 because this might be a case of linking PIC code which is
905 never referenced by a dynamic object, in which case we
906 don't need to generate a procedure linkage table entry
907 after all. */
909 /* If this is a local symbol, we resolve it directly without
910 creating a procedure linkage table entry. */
911 if (h == NULL)
912 continue;
914 h->needs_plt = 1;
915 h->plt.refcount += 1;
916 break;
918 case R_X86_64_PLTOFF64:
919 /* This tries to form the 'address' of a function relative
920 to GOT. For global symbols we need a PLT entry. */
921 if (h != NULL)
923 h->needs_plt = 1;
924 h->plt.refcount += 1;
926 goto create_got;
928 case R_X86_64_8:
929 case R_X86_64_16:
930 case R_X86_64_32:
931 case R_X86_64_32S:
932 /* Let's help debug shared library creation. These relocs
933 cannot be used in shared libs. Don't error out for
934 sections we don't care about, such as debug sections or
935 non-constant sections. */
936 if (info->shared
937 && (sec->flags & SEC_ALLOC) != 0
938 && (sec->flags & SEC_READONLY) != 0)
940 (*_bfd_error_handler)
941 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
942 abfd,
943 x86_64_elf_howto_table[r_type].name,
944 (h) ? h->root.root.string : "a local symbol");
945 bfd_set_error (bfd_error_bad_value);
946 return FALSE;
948 /* Fall through. */
950 case R_X86_64_PC8:
951 case R_X86_64_PC16:
952 case R_X86_64_PC32:
953 case R_X86_64_PC64:
954 case R_X86_64_64:
955 if (h != NULL && !info->shared)
957 /* If this reloc is in a read-only section, we might
958 need a copy reloc. We can't check reliably at this
959 stage whether the section is read-only, as input
960 sections have not yet been mapped to output sections.
961 Tentatively set the flag for now, and correct in
962 adjust_dynamic_symbol. */
963 h->non_got_ref = 1;
965 /* We may need a .plt entry if the function this reloc
966 refers to is in a shared lib. */
967 h->plt.refcount += 1;
968 if (r_type != R_X86_64_PC32 && r_type != R_X86_64_PC64)
969 h->pointer_equality_needed = 1;
972 /* If we are creating a shared library, and this is a reloc
973 against a global symbol, or a non PC relative reloc
974 against a local symbol, then we need to copy the reloc
975 into the shared library. However, if we are linking with
976 -Bsymbolic, we do not need to copy a reloc against a
977 global symbol which is defined in an object we are
978 including in the link (i.e., DEF_REGULAR is set). At
979 this point we have not seen all the input files, so it is
980 possible that DEF_REGULAR is not set now but will be set
981 later (it is never cleared). In case of a weak definition,
982 DEF_REGULAR may be cleared later by a strong definition in
983 a shared library. We account for that possibility below by
984 storing information in the relocs_copied field of the hash
985 table entry. A similar situation occurs when creating
986 shared libraries and symbol visibility changes render the
987 symbol local.
989 If on the other hand, we are creating an executable, we
990 may need to keep relocations for symbols satisfied by a
991 dynamic library if we manage to avoid copy relocs for the
992 symbol. */
993 if ((info->shared
994 && (sec->flags & SEC_ALLOC) != 0
995 && (((r_type != R_X86_64_PC8)
996 && (r_type != R_X86_64_PC16)
997 && (r_type != R_X86_64_PC32)
998 && (r_type != R_X86_64_PC64))
999 || (h != NULL
1000 && (! info->symbolic
1001 || h->root.type == bfd_link_hash_defweak
1002 || !h->def_regular))))
1003 || (ELIMINATE_COPY_RELOCS
1004 && !info->shared
1005 && (sec->flags & SEC_ALLOC) != 0
1006 && h != NULL
1007 && (h->root.type == bfd_link_hash_defweak
1008 || !h->def_regular)))
1010 struct elf64_x86_64_dyn_relocs *p;
1011 struct elf64_x86_64_dyn_relocs **head;
1013 /* We must copy these reloc types into the output file.
1014 Create a reloc section in dynobj and make room for
1015 this reloc. */
1016 if (sreloc == NULL)
1018 const char *name;
1019 bfd *dynobj;
1021 name = (bfd_elf_string_from_elf_section
1022 (abfd,
1023 elf_elfheader (abfd)->e_shstrndx,
1024 elf_section_data (sec)->rel_hdr.sh_name));
1025 if (name == NULL)
1026 return FALSE;
1028 if (strncmp (name, ".rela", 5) != 0
1029 || strcmp (bfd_get_section_name (abfd, sec),
1030 name + 5) != 0)
1032 (*_bfd_error_handler)
1033 (_("%B: bad relocation section name `%s\'"),
1034 abfd, name);
1037 if (htab->elf.dynobj == NULL)
1038 htab->elf.dynobj = abfd;
1040 dynobj = htab->elf.dynobj;
1042 sreloc = bfd_get_section_by_name (dynobj, name);
1043 if (sreloc == NULL)
1045 flagword flags;
1047 flags = (SEC_HAS_CONTENTS | SEC_READONLY
1048 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
1049 if ((sec->flags & SEC_ALLOC) != 0)
1050 flags |= SEC_ALLOC | SEC_LOAD;
1051 sreloc = bfd_make_section_with_flags (dynobj,
1052 name,
1053 flags);
1054 if (sreloc == NULL
1055 || ! bfd_set_section_alignment (dynobj, sreloc, 3))
1056 return FALSE;
1058 elf_section_data (sec)->sreloc = sreloc;
1061 /* If this is a global symbol, we count the number of
1062 relocations we need for this symbol. */
1063 if (h != NULL)
1065 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs;
1067 else
1069 void **vpp;
1070 /* Track dynamic relocs needed for local syms too.
1071 We really need local syms available to do this
1072 easily. Oh well. */
1074 asection *s;
1075 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
1076 sec, r_symndx);
1077 if (s == NULL)
1078 return FALSE;
1080 /* Beware of type punned pointers vs strict aliasing
1081 rules. */
1082 vpp = &(elf_section_data (s)->local_dynrel);
1083 head = (struct elf64_x86_64_dyn_relocs **)vpp;
1086 p = *head;
1087 if (p == NULL || p->sec != sec)
1089 bfd_size_type amt = sizeof *p;
1090 p = ((struct elf64_x86_64_dyn_relocs *)
1091 bfd_alloc (htab->elf.dynobj, amt));
1092 if (p == NULL)
1093 return FALSE;
1094 p->next = *head;
1095 *head = p;
1096 p->sec = sec;
1097 p->count = 0;
1098 p->pc_count = 0;
1101 p->count += 1;
1102 if (r_type == R_X86_64_PC8
1103 || r_type == R_X86_64_PC16
1104 || r_type == R_X86_64_PC32
1105 || r_type == R_X86_64_PC64)
1106 p->pc_count += 1;
1108 break;
1110 /* This relocation describes the C++ object vtable hierarchy.
1111 Reconstruct it for later use during GC. */
1112 case R_X86_64_GNU_VTINHERIT:
1113 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
1114 return FALSE;
1115 break;
1117 /* This relocation describes which C++ vtable entries are actually
1118 used. Record for later use during GC. */
1119 case R_X86_64_GNU_VTENTRY:
1120 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
1121 return FALSE;
1122 break;
1124 default:
1125 break;
1129 return TRUE;
1132 /* Return the section that should be marked against GC for a given
1133 relocation. */
1135 static asection *
1136 elf64_x86_64_gc_mark_hook (asection *sec,
1137 struct bfd_link_info *info ATTRIBUTE_UNUSED,
1138 Elf_Internal_Rela *rel,
1139 struct elf_link_hash_entry *h,
1140 Elf_Internal_Sym *sym)
1142 if (h != NULL)
1144 switch (ELF64_R_TYPE (rel->r_info))
1146 case R_X86_64_GNU_VTINHERIT:
1147 case R_X86_64_GNU_VTENTRY:
1148 break;
1150 default:
1151 switch (h->root.type)
1153 case bfd_link_hash_defined:
1154 case bfd_link_hash_defweak:
1155 return h->root.u.def.section;
1157 case bfd_link_hash_common:
1158 return h->root.u.c.p->section;
1160 default:
1161 break;
1165 else
1166 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
1168 return NULL;
1171 /* Update the got entry reference counts for the section being removed. */
1173 static bfd_boolean
1174 elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
1175 asection *sec, const Elf_Internal_Rela *relocs)
1177 Elf_Internal_Shdr *symtab_hdr;
1178 struct elf_link_hash_entry **sym_hashes;
1179 bfd_signed_vma *local_got_refcounts;
1180 const Elf_Internal_Rela *rel, *relend;
1182 elf_section_data (sec)->local_dynrel = NULL;
1184 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1185 sym_hashes = elf_sym_hashes (abfd);
1186 local_got_refcounts = elf_local_got_refcounts (abfd);
1188 relend = relocs + sec->reloc_count;
1189 for (rel = relocs; rel < relend; rel++)
1191 unsigned long r_symndx;
1192 unsigned int r_type;
1193 struct elf_link_hash_entry *h = NULL;
1195 r_symndx = ELF64_R_SYM (rel->r_info);
1196 if (r_symndx >= symtab_hdr->sh_info)
1198 struct elf64_x86_64_link_hash_entry *eh;
1199 struct elf64_x86_64_dyn_relocs **pp;
1200 struct elf64_x86_64_dyn_relocs *p;
1202 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1203 while (h->root.type == bfd_link_hash_indirect
1204 || h->root.type == bfd_link_hash_warning)
1205 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1206 eh = (struct elf64_x86_64_link_hash_entry *) h;
1208 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1209 if (p->sec == sec)
1211 /* Everything must go for SEC. */
1212 *pp = p->next;
1213 break;
1217 r_type = ELF64_R_TYPE (rel->r_info);
1218 r_type = elf64_x86_64_tls_transition (info, r_type, h != NULL);
1219 switch (r_type)
1221 case R_X86_64_TLSLD:
1222 if (elf64_x86_64_hash_table (info)->tls_ld_got.refcount > 0)
1223 elf64_x86_64_hash_table (info)->tls_ld_got.refcount -= 1;
1224 break;
1226 case R_X86_64_TLSGD:
1227 case R_X86_64_GOTPC32_TLSDESC:
1228 case R_X86_64_TLSDESC_CALL:
1229 case R_X86_64_GOTTPOFF:
1230 case R_X86_64_GOT32:
1231 case R_X86_64_GOTPCREL:
1232 case R_X86_64_GOT64:
1233 case R_X86_64_GOTPCREL64:
1234 case R_X86_64_GOTPLT64:
1235 if (h != NULL)
1237 if (r_type == R_X86_64_GOTPLT64 && h->plt.refcount > 0)
1238 h->plt.refcount -= 1;
1239 if (h->got.refcount > 0)
1240 h->got.refcount -= 1;
1242 else if (local_got_refcounts != NULL)
1244 if (local_got_refcounts[r_symndx] > 0)
1245 local_got_refcounts[r_symndx] -= 1;
1247 break;
1249 case R_X86_64_8:
1250 case R_X86_64_16:
1251 case R_X86_64_32:
1252 case R_X86_64_64:
1253 case R_X86_64_32S:
1254 case R_X86_64_PC8:
1255 case R_X86_64_PC16:
1256 case R_X86_64_PC32:
1257 case R_X86_64_PC64:
1258 if (info->shared)
1259 break;
1260 /* Fall thru */
1262 case R_X86_64_PLT32:
1263 case R_X86_64_PLTOFF64:
1264 if (h != NULL)
1266 if (h->plt.refcount > 0)
1267 h->plt.refcount -= 1;
1269 break;
1271 default:
1272 break;
1276 return TRUE;
1279 /* Adjust a symbol defined by a dynamic object and referenced by a
1280 regular object. The current definition is in some section of the
1281 dynamic object, but we're not including those sections. We have to
1282 change the definition to something the rest of the link can
1283 understand. */
1285 static bfd_boolean
1286 elf64_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
1287 struct elf_link_hash_entry *h)
1289 struct elf64_x86_64_link_hash_table *htab;
1290 asection *s;
1291 unsigned int power_of_two;
1293 /* If this is a function, put it in the procedure linkage table. We
1294 will fill in the contents of the procedure linkage table later,
1295 when we know the address of the .got section. */
1296 if (h->type == STT_FUNC
1297 || h->needs_plt)
1299 if (h->plt.refcount <= 0
1300 || SYMBOL_CALLS_LOCAL (info, h)
1301 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1302 && h->root.type == bfd_link_hash_undefweak))
1304 /* This case can occur if we saw a PLT32 reloc in an input
1305 file, but the symbol was never referred to by a dynamic
1306 object, or if all references were garbage collected. In
1307 such a case, we don't actually need to build a procedure
1308 linkage table, and we can just do a PC32 reloc instead. */
1309 h->plt.offset = (bfd_vma) -1;
1310 h->needs_plt = 0;
1313 return TRUE;
1315 else
1316 /* It's possible that we incorrectly decided a .plt reloc was
1317 needed for an R_X86_64_PC32 reloc to a non-function sym in
1318 check_relocs. We can't decide accurately between function and
1319 non-function syms in check-relocs; Objects loaded later in
1320 the link may change h->type. So fix it now. */
1321 h->plt.offset = (bfd_vma) -1;
1323 /* If this is a weak symbol, and there is a real definition, the
1324 processor independent code will have arranged for us to see the
1325 real definition first, and we can just use the same value. */
1326 if (h->u.weakdef != NULL)
1328 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1329 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1330 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1331 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1332 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1333 h->non_got_ref = h->u.weakdef->non_got_ref;
1334 return TRUE;
1337 /* This is a reference to a symbol defined by a dynamic object which
1338 is not a function. */
1340 /* If we are creating a shared library, we must presume that the
1341 only references to the symbol are via the global offset table.
1342 For such cases we need not do anything here; the relocations will
1343 be handled correctly by relocate_section. */
1344 if (info->shared)
1345 return TRUE;
1347 /* If there are no references to this symbol that do not use the
1348 GOT, we don't need to generate a copy reloc. */
1349 if (!h->non_got_ref)
1350 return TRUE;
1352 /* If -z nocopyreloc was given, we won't generate them either. */
1353 if (info->nocopyreloc)
1355 h->non_got_ref = 0;
1356 return TRUE;
1359 if (ELIMINATE_COPY_RELOCS)
1361 struct elf64_x86_64_link_hash_entry * eh;
1362 struct elf64_x86_64_dyn_relocs *p;
1364 eh = (struct elf64_x86_64_link_hash_entry *) h;
1365 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1367 s = p->sec->output_section;
1368 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1369 break;
1372 /* If we didn't find any dynamic relocs in read-only sections, then
1373 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1374 if (p == NULL)
1376 h->non_got_ref = 0;
1377 return TRUE;
1381 if (h->size == 0)
1383 (*_bfd_error_handler) (_("dynamic variable `%s' is zero size"),
1384 h->root.root.string);
1385 return TRUE;
1388 /* We must allocate the symbol in our .dynbss section, which will
1389 become part of the .bss section of the executable. There will be
1390 an entry for this symbol in the .dynsym section. The dynamic
1391 object will contain position independent code, so all references
1392 from the dynamic object to this symbol will go through the global
1393 offset table. The dynamic linker will use the .dynsym entry to
1394 determine the address it must put in the global offset table, so
1395 both the dynamic object and the regular object will refer to the
1396 same memory location for the variable. */
1398 htab = elf64_x86_64_hash_table (info);
1400 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
1401 to copy the initial value out of the dynamic object and into the
1402 runtime process image. */
1403 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1405 htab->srelbss->size += sizeof (Elf64_External_Rela);
1406 h->needs_copy = 1;
1409 /* We need to figure out the alignment required for this symbol. I
1410 have no idea how ELF linkers handle this. 16-bytes is the size
1411 of the largest type that requires hard alignment -- long double. */
1412 /* FIXME: This is VERY ugly. Should be fixed for all architectures using
1413 this construct. */
1414 power_of_two = bfd_log2 (h->size);
1415 if (power_of_two > 4)
1416 power_of_two = 4;
1418 /* Apply the required alignment. */
1419 s = htab->sdynbss;
1420 s->size = BFD_ALIGN (s->size, (bfd_size_type) (1 << power_of_two));
1421 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1423 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1424 return FALSE;
1427 /* Define the symbol as being at this point in the section. */
1428 h->root.u.def.section = s;
1429 h->root.u.def.value = s->size;
1431 /* Increment the section size to make room for the symbol. */
1432 s->size += h->size;
1434 return TRUE;
1437 /* Allocate space in .plt, .got and associated reloc sections for
1438 dynamic relocs. */
1440 static bfd_boolean
1441 allocate_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1443 struct bfd_link_info *info;
1444 struct elf64_x86_64_link_hash_table *htab;
1445 struct elf64_x86_64_link_hash_entry *eh;
1446 struct elf64_x86_64_dyn_relocs *p;
1448 if (h->root.type == bfd_link_hash_indirect)
1449 return TRUE;
1451 if (h->root.type == bfd_link_hash_warning)
1452 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1454 info = (struct bfd_link_info *) inf;
1455 htab = elf64_x86_64_hash_table (info);
1457 if (htab->elf.dynamic_sections_created
1458 && h->plt.refcount > 0)
1460 /* Make sure this symbol is output as a dynamic symbol.
1461 Undefined weak syms won't yet be marked as dynamic. */
1462 if (h->dynindx == -1
1463 && !h->forced_local)
1465 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1466 return FALSE;
1469 if (info->shared
1470 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
1472 asection *s = htab->splt;
1474 /* If this is the first .plt entry, make room for the special
1475 first entry. */
1476 if (s->size == 0)
1477 s->size += PLT_ENTRY_SIZE;
1479 h->plt.offset = s->size;
1481 /* If this symbol is not defined in a regular file, and we are
1482 not generating a shared library, then set the symbol to this
1483 location in the .plt. This is required to make function
1484 pointers compare as equal between the normal executable and
1485 the shared library. */
1486 if (! info->shared
1487 && !h->def_regular)
1489 h->root.u.def.section = s;
1490 h->root.u.def.value = h->plt.offset;
1493 /* Make room for this entry. */
1494 s->size += PLT_ENTRY_SIZE;
1496 /* We also need to make an entry in the .got.plt section, which
1497 will be placed in the .got section by the linker script. */
1498 htab->sgotplt->size += GOT_ENTRY_SIZE;
1500 /* We also need to make an entry in the .rela.plt section. */
1501 htab->srelplt->size += sizeof (Elf64_External_Rela);
1502 htab->srelplt->reloc_count++;
1504 else
1506 h->plt.offset = (bfd_vma) -1;
1507 h->needs_plt = 0;
1510 else
1512 h->plt.offset = (bfd_vma) -1;
1513 h->needs_plt = 0;
1516 eh = (struct elf64_x86_64_link_hash_entry *) h;
1517 eh->tlsdesc_got = (bfd_vma) -1;
1519 /* If R_X86_64_GOTTPOFF symbol is now local to the binary,
1520 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
1521 if (h->got.refcount > 0
1522 && !info->shared
1523 && h->dynindx == -1
1524 && elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
1525 h->got.offset = (bfd_vma) -1;
1526 else if (h->got.refcount > 0)
1528 asection *s;
1529 bfd_boolean dyn;
1530 int tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1532 /* Make sure this symbol is output as a dynamic symbol.
1533 Undefined weak syms won't yet be marked as dynamic. */
1534 if (h->dynindx == -1
1535 && !h->forced_local)
1537 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1538 return FALSE;
1541 if (GOT_TLS_GDESC_P (tls_type))
1543 eh->tlsdesc_got = htab->sgotplt->size
1544 - elf64_x86_64_compute_jump_table_size (htab);
1545 htab->sgotplt->size += 2 * GOT_ENTRY_SIZE;
1546 h->got.offset = (bfd_vma) -2;
1548 if (! GOT_TLS_GDESC_P (tls_type)
1549 || GOT_TLS_GD_P (tls_type))
1551 s = htab->sgot;
1552 h->got.offset = s->size;
1553 s->size += GOT_ENTRY_SIZE;
1554 if (GOT_TLS_GD_P (tls_type))
1555 s->size += GOT_ENTRY_SIZE;
1557 dyn = htab->elf.dynamic_sections_created;
1558 /* R_X86_64_TLSGD needs one dynamic relocation if local symbol
1559 and two if global.
1560 R_X86_64_GOTTPOFF needs one dynamic relocation. */
1561 if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1)
1562 || tls_type == GOT_TLS_IE)
1563 htab->srelgot->size += sizeof (Elf64_External_Rela);
1564 else if (GOT_TLS_GD_P (tls_type))
1565 htab->srelgot->size += 2 * sizeof (Elf64_External_Rela);
1566 else if (! GOT_TLS_GDESC_P (tls_type)
1567 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1568 || h->root.type != bfd_link_hash_undefweak)
1569 && (info->shared
1570 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
1571 htab->srelgot->size += sizeof (Elf64_External_Rela);
1572 if (GOT_TLS_GDESC_P (tls_type))
1574 htab->srelplt->size += sizeof (Elf64_External_Rela);
1575 htab->tlsdesc_plt = (bfd_vma) -1;
1578 else
1579 h->got.offset = (bfd_vma) -1;
1581 if (eh->dyn_relocs == NULL)
1582 return TRUE;
1584 /* In the shared -Bsymbolic case, discard space allocated for
1585 dynamic pc-relative relocs against symbols which turn out to be
1586 defined in regular objects. For the normal shared case, discard
1587 space for pc-relative relocs that have become local due to symbol
1588 visibility changes. */
1590 if (info->shared)
1592 /* Relocs that use pc_count are those that appear on a call
1593 insn, or certain REL relocs that can generated via assembly.
1594 We want calls to protected symbols to resolve directly to the
1595 function rather than going via the plt. If people want
1596 function pointer comparisons to work as expected then they
1597 should avoid writing weird assembly. */
1598 if (SYMBOL_CALLS_LOCAL (info, h))
1600 struct elf64_x86_64_dyn_relocs **pp;
1602 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1604 p->count -= p->pc_count;
1605 p->pc_count = 0;
1606 if (p->count == 0)
1607 *pp = p->next;
1608 else
1609 pp = &p->next;
1613 /* Also discard relocs on undefined weak syms with non-default
1614 visibility. */
1615 if (eh->dyn_relocs != NULL
1616 && h->root.type == bfd_link_hash_undefweak)
1618 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
1619 eh->dyn_relocs = NULL;
1621 /* Make sure undefined weak symbols are output as a dynamic
1622 symbol in PIEs. */
1623 else if (h->dynindx == -1
1624 && !h->forced_local)
1626 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1627 return FALSE;
1631 else if (ELIMINATE_COPY_RELOCS)
1633 /* For the non-shared case, discard space for relocs against
1634 symbols which turn out to need copy relocs or are not
1635 dynamic. */
1637 if (!h->non_got_ref
1638 && ((h->def_dynamic
1639 && !h->def_regular)
1640 || (htab->elf.dynamic_sections_created
1641 && (h->root.type == bfd_link_hash_undefweak
1642 || h->root.type == bfd_link_hash_undefined))))
1644 /* Make sure this symbol is output as a dynamic symbol.
1645 Undefined weak syms won't yet be marked as dynamic. */
1646 if (h->dynindx == -1
1647 && !h->forced_local)
1649 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1650 return FALSE;
1653 /* If that succeeded, we know we'll be keeping all the
1654 relocs. */
1655 if (h->dynindx != -1)
1656 goto keep;
1659 eh->dyn_relocs = NULL;
1661 keep: ;
1664 /* Finally, allocate space. */
1665 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1667 asection *sreloc = elf_section_data (p->sec)->sreloc;
1668 sreloc->size += p->count * sizeof (Elf64_External_Rela);
1671 return TRUE;
1674 /* Find any dynamic relocs that apply to read-only sections. */
1676 static bfd_boolean
1677 readonly_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1679 struct elf64_x86_64_link_hash_entry *eh;
1680 struct elf64_x86_64_dyn_relocs *p;
1682 if (h->root.type == bfd_link_hash_warning)
1683 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1685 eh = (struct elf64_x86_64_link_hash_entry *) h;
1686 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1688 asection *s = p->sec->output_section;
1690 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1692 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1694 info->flags |= DF_TEXTREL;
1696 /* Not an error, just cut short the traversal. */
1697 return FALSE;
1700 return TRUE;
1703 /* Set the sizes of the dynamic sections. */
1705 static bfd_boolean
1706 elf64_x86_64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
1707 struct bfd_link_info *info)
1709 struct elf64_x86_64_link_hash_table *htab;
1710 bfd *dynobj;
1711 asection *s;
1712 bfd_boolean relocs;
1713 bfd *ibfd;
1715 htab = elf64_x86_64_hash_table (info);
1716 dynobj = htab->elf.dynobj;
1717 if (dynobj == NULL)
1718 abort ();
1720 if (htab->elf.dynamic_sections_created)
1722 /* Set the contents of the .interp section to the interpreter. */
1723 if (info->executable)
1725 s = bfd_get_section_by_name (dynobj, ".interp");
1726 if (s == NULL)
1727 abort ();
1728 s->size = sizeof ELF_DYNAMIC_INTERPRETER;
1729 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1733 /* Set up .got offsets for local syms, and space for local dynamic
1734 relocs. */
1735 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1737 bfd_signed_vma *local_got;
1738 bfd_signed_vma *end_local_got;
1739 char *local_tls_type;
1740 bfd_vma *local_tlsdesc_gotent;
1741 bfd_size_type locsymcount;
1742 Elf_Internal_Shdr *symtab_hdr;
1743 asection *srel;
1745 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1746 continue;
1748 for (s = ibfd->sections; s != NULL; s = s->next)
1750 struct elf64_x86_64_dyn_relocs *p;
1752 for (p = (struct elf64_x86_64_dyn_relocs *)
1753 (elf_section_data (s)->local_dynrel);
1754 p != NULL;
1755 p = p->next)
1757 if (!bfd_is_abs_section (p->sec)
1758 && bfd_is_abs_section (p->sec->output_section))
1760 /* Input section has been discarded, either because
1761 it is a copy of a linkonce section or due to
1762 linker script /DISCARD/, so we'll be discarding
1763 the relocs too. */
1765 else if (p->count != 0)
1767 srel = elf_section_data (p->sec)->sreloc;
1768 srel->size += p->count * sizeof (Elf64_External_Rela);
1769 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1770 info->flags |= DF_TEXTREL;
1776 local_got = elf_local_got_refcounts (ibfd);
1777 if (!local_got)
1778 continue;
1780 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1781 locsymcount = symtab_hdr->sh_info;
1782 end_local_got = local_got + locsymcount;
1783 local_tls_type = elf64_x86_64_local_got_tls_type (ibfd);
1784 local_tlsdesc_gotent = elf64_x86_64_local_tlsdesc_gotent (ibfd);
1785 s = htab->sgot;
1786 srel = htab->srelgot;
1787 for (; local_got < end_local_got;
1788 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent)
1790 *local_tlsdesc_gotent = (bfd_vma) -1;
1791 if (*local_got > 0)
1793 if (GOT_TLS_GDESC_P (*local_tls_type))
1795 *local_tlsdesc_gotent = htab->sgotplt->size
1796 - elf64_x86_64_compute_jump_table_size (htab);
1797 htab->sgotplt->size += 2 * GOT_ENTRY_SIZE;
1798 *local_got = (bfd_vma) -2;
1800 if (! GOT_TLS_GDESC_P (*local_tls_type)
1801 || GOT_TLS_GD_P (*local_tls_type))
1803 *local_got = s->size;
1804 s->size += GOT_ENTRY_SIZE;
1805 if (GOT_TLS_GD_P (*local_tls_type))
1806 s->size += GOT_ENTRY_SIZE;
1808 if (info->shared
1809 || GOT_TLS_GD_ANY_P (*local_tls_type)
1810 || *local_tls_type == GOT_TLS_IE)
1812 if (GOT_TLS_GDESC_P (*local_tls_type))
1814 htab->srelplt->size += sizeof (Elf64_External_Rela);
1815 htab->tlsdesc_plt = (bfd_vma) -1;
1817 if (! GOT_TLS_GDESC_P (*local_tls_type)
1818 || GOT_TLS_GD_P (*local_tls_type))
1819 srel->size += sizeof (Elf64_External_Rela);
1822 else
1823 *local_got = (bfd_vma) -1;
1827 if (htab->tls_ld_got.refcount > 0)
1829 /* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD
1830 relocs. */
1831 htab->tls_ld_got.offset = htab->sgot->size;
1832 htab->sgot->size += 2 * GOT_ENTRY_SIZE;
1833 htab->srelgot->size += sizeof (Elf64_External_Rela);
1835 else
1836 htab->tls_ld_got.offset = -1;
1838 /* Allocate global sym .plt and .got entries, and space for global
1839 sym dynamic relocs. */
1840 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1842 /* For every jump slot reserved in the sgotplt, reloc_count is
1843 incremented. However, when we reserve space for TLS descriptors,
1844 it's not incremented, so in order to compute the space reserved
1845 for them, it suffices to multiply the reloc count by the jump
1846 slot size. */
1847 if (htab->srelplt)
1848 htab->sgotplt_jump_table_size
1849 = elf64_x86_64_compute_jump_table_size (htab);
1851 if (htab->tlsdesc_plt)
1853 /* If we're not using lazy TLS relocations, don't generate the
1854 PLT and GOT entries they require. */
1855 if ((info->flags & DF_BIND_NOW))
1856 htab->tlsdesc_plt = 0;
1857 else
1859 htab->tlsdesc_got = htab->sgot->size;
1860 htab->sgot->size += GOT_ENTRY_SIZE;
1861 /* Reserve room for the initial entry.
1862 FIXME: we could probably do away with it in this case. */
1863 if (htab->splt->size == 0)
1864 htab->splt->size += PLT_ENTRY_SIZE;
1865 htab->tlsdesc_plt = htab->splt->size;
1866 htab->splt->size += PLT_ENTRY_SIZE;
1870 /* We now have determined the sizes of the various dynamic sections.
1871 Allocate memory for them. */
1872 relocs = FALSE;
1873 for (s = dynobj->sections; s != NULL; s = s->next)
1875 if ((s->flags & SEC_LINKER_CREATED) == 0)
1876 continue;
1878 if (s == htab->splt
1879 || s == htab->sgot
1880 || s == htab->sgotplt
1881 || s == htab->sdynbss)
1883 /* Strip this section if we don't need it; see the
1884 comment below. */
1886 else if (strncmp (bfd_get_section_name (dynobj, s), ".rela", 5) == 0)
1888 if (s->size != 0 && s != htab->srelplt)
1889 relocs = TRUE;
1891 /* We use the reloc_count field as a counter if we need
1892 to copy relocs into the output file. */
1893 if (s != htab->srelplt)
1894 s->reloc_count = 0;
1896 else
1898 /* It's not one of our sections, so don't allocate space. */
1899 continue;
1902 if (s->size == 0)
1904 /* If we don't need this section, strip it from the
1905 output file. This is mostly to handle .rela.bss and
1906 .rela.plt. We must create both sections in
1907 create_dynamic_sections, because they must be created
1908 before the linker maps input sections to output
1909 sections. The linker does that before
1910 adjust_dynamic_symbol is called, and it is that
1911 function which decides whether anything needs to go
1912 into these sections. */
1914 s->flags |= SEC_EXCLUDE;
1915 continue;
1918 if ((s->flags & SEC_HAS_CONTENTS) == 0)
1919 continue;
1921 /* Allocate memory for the section contents. We use bfd_zalloc
1922 here in case unused entries are not reclaimed before the
1923 section's contents are written out. This should not happen,
1924 but this way if it does, we get a R_X86_64_NONE reloc instead
1925 of garbage. */
1926 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->size);
1927 if (s->contents == NULL)
1928 return FALSE;
1931 if (htab->elf.dynamic_sections_created)
1933 /* Add some entries to the .dynamic section. We fill in the
1934 values later, in elf64_x86_64_finish_dynamic_sections, but we
1935 must add the entries now so that we get the correct size for
1936 the .dynamic section. The DT_DEBUG entry is filled in by the
1937 dynamic linker and used by the debugger. */
1938 #define add_dynamic_entry(TAG, VAL) \
1939 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1941 if (info->executable)
1943 if (!add_dynamic_entry (DT_DEBUG, 0))
1944 return FALSE;
1947 if (htab->splt->size != 0)
1949 if (!add_dynamic_entry (DT_PLTGOT, 0)
1950 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1951 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1952 || !add_dynamic_entry (DT_JMPREL, 0))
1953 return FALSE;
1955 if (htab->tlsdesc_plt
1956 && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
1957 || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
1958 return FALSE;
1961 if (relocs)
1963 if (!add_dynamic_entry (DT_RELA, 0)
1964 || !add_dynamic_entry (DT_RELASZ, 0)
1965 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
1966 return FALSE;
1968 /* If any dynamic relocs apply to a read-only section,
1969 then we need a DT_TEXTREL entry. */
1970 if ((info->flags & DF_TEXTREL) == 0)
1971 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
1972 (PTR) info);
1974 if ((info->flags & DF_TEXTREL) != 0)
1976 if (!add_dynamic_entry (DT_TEXTREL, 0))
1977 return FALSE;
1981 #undef add_dynamic_entry
1983 return TRUE;
1986 static bfd_boolean
1987 elf64_x86_64_always_size_sections (bfd *output_bfd,
1988 struct bfd_link_info *info)
1990 asection *tls_sec = elf_hash_table (info)->tls_sec;
1992 if (tls_sec)
1994 struct elf_link_hash_entry *tlsbase;
1996 tlsbase = elf_link_hash_lookup (elf_hash_table (info),
1997 "_TLS_MODULE_BASE_",
1998 FALSE, FALSE, FALSE);
2000 if (tlsbase && tlsbase->type == STT_TLS)
2002 struct bfd_link_hash_entry *bh = NULL;
2003 const struct elf_backend_data *bed
2004 = get_elf_backend_data (output_bfd);
2006 if (!(_bfd_generic_link_add_one_symbol
2007 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL,
2008 tls_sec, 0, NULL, FALSE,
2009 bed->collect, &bh)))
2010 return FALSE;
2011 tlsbase = (struct elf_link_hash_entry *)bh;
2012 tlsbase->def_regular = 1;
2013 tlsbase->other = STV_HIDDEN;
2014 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE);
2018 return TRUE;
2021 /* Return the base VMA address which should be subtracted from real addresses
2022 when resolving @dtpoff relocation.
2023 This is PT_TLS segment p_vaddr. */
2025 static bfd_vma
2026 dtpoff_base (struct bfd_link_info *info)
2028 /* If tls_sec is NULL, we should have signalled an error already. */
2029 if (elf_hash_table (info)->tls_sec == NULL)
2030 return 0;
2031 return elf_hash_table (info)->tls_sec->vma;
2034 /* Return the relocation value for @tpoff relocation
2035 if STT_TLS virtual address is ADDRESS. */
2037 static bfd_vma
2038 tpoff (struct bfd_link_info *info, bfd_vma address)
2040 struct elf_link_hash_table *htab = elf_hash_table (info);
2042 /* If tls_segment is NULL, we should have signalled an error already. */
2043 if (htab->tls_sec == NULL)
2044 return 0;
2045 return address - htab->tls_size - htab->tls_sec->vma;
2048 /* Is the instruction before OFFSET in CONTENTS a 32bit relative
2049 branch? */
2051 static bfd_boolean
2052 is_32bit_relative_branch (bfd_byte *contents, bfd_vma offset)
2054 /* Opcode Instruction
2055 0xe8 call
2056 0xe9 jump
2057 0x0f 0x8x conditional jump */
2058 return ((offset > 0
2059 && (contents [offset - 1] == 0xe8
2060 || contents [offset - 1] == 0xe9))
2061 || (offset > 1
2062 && contents [offset - 2] == 0x0f
2063 && (contents [offset - 1] & 0xf0) == 0x80));
2066 /* Relocate an x86_64 ELF section. */
2068 static bfd_boolean
2069 elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
2070 bfd *input_bfd, asection *input_section,
2071 bfd_byte *contents, Elf_Internal_Rela *relocs,
2072 Elf_Internal_Sym *local_syms,
2073 asection **local_sections)
2075 struct elf64_x86_64_link_hash_table *htab;
2076 Elf_Internal_Shdr *symtab_hdr;
2077 struct elf_link_hash_entry **sym_hashes;
2078 bfd_vma *local_got_offsets;
2079 bfd_vma *local_tlsdesc_gotents;
2080 Elf_Internal_Rela *rel;
2081 Elf_Internal_Rela *relend;
2083 if (info->relocatable)
2084 return TRUE;
2086 htab = elf64_x86_64_hash_table (info);
2087 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2088 sym_hashes = elf_sym_hashes (input_bfd);
2089 local_got_offsets = elf_local_got_offsets (input_bfd);
2090 local_tlsdesc_gotents = elf64_x86_64_local_tlsdesc_gotent (input_bfd);
2092 rel = relocs;
2093 relend = relocs + input_section->reloc_count;
2094 for (; rel < relend; rel++)
2096 unsigned int r_type;
2097 reloc_howto_type *howto;
2098 unsigned long r_symndx;
2099 struct elf_link_hash_entry *h;
2100 Elf_Internal_Sym *sym;
2101 asection *sec;
2102 bfd_vma off, offplt;
2103 bfd_vma relocation;
2104 bfd_boolean unresolved_reloc;
2105 bfd_reloc_status_type r;
2106 int tls_type;
2108 r_type = ELF64_R_TYPE (rel->r_info);
2109 if (r_type == (int) R_X86_64_GNU_VTINHERIT
2110 || r_type == (int) R_X86_64_GNU_VTENTRY)
2111 continue;
2113 if (r_type >= R_X86_64_max)
2115 bfd_set_error (bfd_error_bad_value);
2116 return FALSE;
2119 howto = x86_64_elf_howto_table + r_type;
2120 r_symndx = ELF64_R_SYM (rel->r_info);
2121 h = NULL;
2122 sym = NULL;
2123 sec = NULL;
2124 unresolved_reloc = FALSE;
2125 if (r_symndx < symtab_hdr->sh_info)
2127 sym = local_syms + r_symndx;
2128 sec = local_sections[r_symndx];
2130 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
2132 else
2134 bfd_boolean warned;
2136 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
2137 r_symndx, symtab_hdr, sym_hashes,
2138 h, sec, relocation,
2139 unresolved_reloc, warned);
2141 /* When generating a shared object, the relocations handled here are
2142 copied into the output file to be resolved at run time. */
2143 switch (r_type)
2145 asection *base_got;
2146 case R_X86_64_GOT32:
2147 case R_X86_64_GOT64:
2148 /* Relocation is to the entry for this symbol in the global
2149 offset table. */
2150 case R_X86_64_GOTPCREL:
2151 case R_X86_64_GOTPCREL64:
2152 /* Use global offset table entry as symbol value. */
2153 case R_X86_64_GOTPLT64:
2154 /* This is the same as GOT64 for relocation purposes, but
2155 indicates the existence of a PLT entry. The difficulty is,
2156 that we must calculate the GOT slot offset from the PLT
2157 offset, if this symbol got a PLT entry (it was global).
2158 Additionally if it's computed from the PLT entry, then that
2159 GOT offset is relative to .got.plt, not to .got. */
2160 base_got = htab->sgot;
2162 if (htab->sgot == NULL)
2163 abort ();
2165 if (h != NULL)
2167 bfd_boolean dyn;
2169 off = h->got.offset;
2170 if (h->needs_plt
2171 && h->plt.offset != (bfd_vma)-1
2172 && off == (bfd_vma)-1)
2174 /* We can't use h->got.offset here to save
2175 state, or even just remember the offset, as
2176 finish_dynamic_symbol would use that as offset into
2177 .got. */
2178 bfd_vma plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2179 off = (plt_index + 3) * GOT_ENTRY_SIZE;
2180 base_got = htab->sgotplt;
2183 dyn = htab->elf.dynamic_sections_created;
2185 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
2186 || (info->shared
2187 && SYMBOL_REFERENCES_LOCAL (info, h))
2188 || (ELF_ST_VISIBILITY (h->other)
2189 && h->root.type == bfd_link_hash_undefweak))
2191 /* This is actually a static link, or it is a -Bsymbolic
2192 link and the symbol is defined locally, or the symbol
2193 was forced to be local because of a version file. We
2194 must initialize this entry in the global offset table.
2195 Since the offset must always be a multiple of 8, we
2196 use the least significant bit to record whether we
2197 have initialized it already.
2199 When doing a dynamic link, we create a .rela.got
2200 relocation entry to initialize the value. This is
2201 done in the finish_dynamic_symbol routine. */
2202 if ((off & 1) != 0)
2203 off &= ~1;
2204 else
2206 bfd_put_64 (output_bfd, relocation,
2207 base_got->contents + off);
2208 /* Note that this is harmless for the GOTPLT64 case,
2209 as -1 | 1 still is -1. */
2210 h->got.offset |= 1;
2213 else
2214 unresolved_reloc = FALSE;
2216 else
2218 if (local_got_offsets == NULL)
2219 abort ();
2221 off = local_got_offsets[r_symndx];
2223 /* The offset must always be a multiple of 8. We use
2224 the least significant bit to record whether we have
2225 already generated the necessary reloc. */
2226 if ((off & 1) != 0)
2227 off &= ~1;
2228 else
2230 bfd_put_64 (output_bfd, relocation,
2231 base_got->contents + off);
2233 if (info->shared)
2235 asection *s;
2236 Elf_Internal_Rela outrel;
2237 bfd_byte *loc;
2239 /* We need to generate a R_X86_64_RELATIVE reloc
2240 for the dynamic linker. */
2241 s = htab->srelgot;
2242 if (s == NULL)
2243 abort ();
2245 outrel.r_offset = (base_got->output_section->vma
2246 + base_got->output_offset
2247 + off);
2248 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2249 outrel.r_addend = relocation;
2250 loc = s->contents;
2251 loc += s->reloc_count++ * sizeof (Elf64_External_Rela);
2252 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2255 local_got_offsets[r_symndx] |= 1;
2259 if (off >= (bfd_vma) -2)
2260 abort ();
2262 relocation = base_got->output_section->vma
2263 + base_got->output_offset + off;
2264 if (r_type != R_X86_64_GOTPCREL && r_type != R_X86_64_GOTPCREL64)
2265 relocation -= htab->sgotplt->output_section->vma
2266 - htab->sgotplt->output_offset;
2268 break;
2270 case R_X86_64_GOTOFF64:
2271 /* Relocation is relative to the start of the global offset
2272 table. */
2274 /* Check to make sure it isn't a protected function symbol
2275 for shared library since it may not be local when used
2276 as function address. */
2277 if (info->shared
2278 && h
2279 && h->def_regular
2280 && h->type == STT_FUNC
2281 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
2283 (*_bfd_error_handler)
2284 (_("%B: relocation R_X86_64_GOTOFF64 against protected function `%s' can not be used when making a shared object"),
2285 input_bfd, h->root.root.string);
2286 bfd_set_error (bfd_error_bad_value);
2287 return FALSE;
2290 /* Note that sgot is not involved in this
2291 calculation. We always want the start of .got.plt. If we
2292 defined _GLOBAL_OFFSET_TABLE_ in a different way, as is
2293 permitted by the ABI, we might have to change this
2294 calculation. */
2295 relocation -= htab->sgotplt->output_section->vma
2296 + htab->sgotplt->output_offset;
2297 break;
2299 case R_X86_64_GOTPC32:
2300 case R_X86_64_GOTPC64:
2301 /* Use global offset table as symbol value. */
2302 relocation = htab->sgotplt->output_section->vma
2303 + htab->sgotplt->output_offset;
2304 unresolved_reloc = FALSE;
2305 break;
2307 case R_X86_64_PLTOFF64:
2308 /* Relocation is PLT entry relative to GOT. For local
2309 symbols it's the symbol itself relative to GOT. */
2310 if (h != NULL
2311 /* See PLT32 handling. */
2312 && h->plt.offset != (bfd_vma) -1
2313 && htab->splt != NULL)
2315 relocation = (htab->splt->output_section->vma
2316 + htab->splt->output_offset
2317 + h->plt.offset);
2318 unresolved_reloc = FALSE;
2321 relocation -= htab->sgotplt->output_section->vma
2322 + htab->sgotplt->output_offset;
2323 break;
2325 case R_X86_64_PLT32:
2326 /* Relocation is to the entry for this symbol in the
2327 procedure linkage table. */
2329 /* Resolve a PLT32 reloc against a local symbol directly,
2330 without using the procedure linkage table. */
2331 if (h == NULL)
2332 break;
2334 if (h->plt.offset == (bfd_vma) -1
2335 || htab->splt == NULL)
2337 /* We didn't make a PLT entry for this symbol. This
2338 happens when statically linking PIC code, or when
2339 using -Bsymbolic. */
2340 break;
2343 relocation = (htab->splt->output_section->vma
2344 + htab->splt->output_offset
2345 + h->plt.offset);
2346 unresolved_reloc = FALSE;
2347 break;
2349 case R_X86_64_PC8:
2350 case R_X86_64_PC16:
2351 case R_X86_64_PC32:
2352 if (info->shared
2353 && !SYMBOL_REFERENCES_LOCAL (info, h)
2354 && (input_section->flags & SEC_ALLOC) != 0
2355 && (input_section->flags & SEC_READONLY) != 0
2356 && (!h->def_regular
2357 || r_type != R_X86_64_PC32
2358 || h->type != STT_FUNC
2359 || ELF_ST_VISIBILITY (h->other) != STV_PROTECTED
2360 || !is_32bit_relative_branch (contents,
2361 rel->r_offset)))
2363 if (h->def_regular
2364 && r_type == R_X86_64_PC32
2365 && h->type == STT_FUNC
2366 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
2367 (*_bfd_error_handler)
2368 (_("%B: relocation R_X86_64_PC32 against protected function `%s' can not be used when making a shared object"),
2369 input_bfd, h->root.root.string);
2370 else
2371 (*_bfd_error_handler)
2372 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
2373 input_bfd, x86_64_elf_howto_table[r_type].name,
2374 h->root.root.string);
2375 bfd_set_error (bfd_error_bad_value);
2376 return FALSE;
2378 /* Fall through. */
2380 case R_X86_64_8:
2381 case R_X86_64_16:
2382 case R_X86_64_32:
2383 case R_X86_64_PC64:
2384 case R_X86_64_64:
2385 /* FIXME: The ABI says the linker should make sure the value is
2386 the same when it's zeroextended to 64 bit. */
2388 /* r_symndx will be zero only for relocs against symbols
2389 from removed linkonce sections, or sections discarded by
2390 a linker script. */
2391 if (r_symndx == 0
2392 || (input_section->flags & SEC_ALLOC) == 0)
2393 break;
2395 if ((info->shared
2396 && (h == NULL
2397 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
2398 || h->root.type != bfd_link_hash_undefweak)
2399 && ((r_type != R_X86_64_PC8
2400 && r_type != R_X86_64_PC16
2401 && r_type != R_X86_64_PC32
2402 && r_type != R_X86_64_PC64)
2403 || !SYMBOL_CALLS_LOCAL (info, h)))
2404 || (ELIMINATE_COPY_RELOCS
2405 && !info->shared
2406 && h != NULL
2407 && h->dynindx != -1
2408 && !h->non_got_ref
2409 && ((h->def_dynamic
2410 && !h->def_regular)
2411 || h->root.type == bfd_link_hash_undefweak
2412 || h->root.type == bfd_link_hash_undefined)))
2414 Elf_Internal_Rela outrel;
2415 bfd_byte *loc;
2416 bfd_boolean skip, relocate;
2417 asection *sreloc;
2419 /* When generating a shared object, these relocations
2420 are copied into the output file to be resolved at run
2421 time. */
2422 skip = FALSE;
2423 relocate = FALSE;
2425 outrel.r_offset =
2426 _bfd_elf_section_offset (output_bfd, info, input_section,
2427 rel->r_offset);
2428 if (outrel.r_offset == (bfd_vma) -1)
2429 skip = TRUE;
2430 else if (outrel.r_offset == (bfd_vma) -2)
2431 skip = TRUE, relocate = TRUE;
2433 outrel.r_offset += (input_section->output_section->vma
2434 + input_section->output_offset);
2436 if (skip)
2437 memset (&outrel, 0, sizeof outrel);
2439 /* h->dynindx may be -1 if this symbol was marked to
2440 become local. */
2441 else if (h != NULL
2442 && h->dynindx != -1
2443 && (r_type == R_X86_64_PC8
2444 || r_type == R_X86_64_PC16
2445 || r_type == R_X86_64_PC32
2446 || r_type == R_X86_64_PC64
2447 || !info->shared
2448 || !info->symbolic
2449 || !h->def_regular))
2451 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
2452 outrel.r_addend = rel->r_addend;
2454 else
2456 /* This symbol is local, or marked to become local. */
2457 if (r_type == R_X86_64_64)
2459 relocate = TRUE;
2460 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2461 outrel.r_addend = relocation + rel->r_addend;
2463 else
2465 long sindx;
2467 if (bfd_is_abs_section (sec))
2468 sindx = 0;
2469 else if (sec == NULL || sec->owner == NULL)
2471 bfd_set_error (bfd_error_bad_value);
2472 return FALSE;
2474 else
2476 asection *osec;
2478 osec = sec->output_section;
2479 sindx = elf_section_data (osec)->dynindx;
2480 BFD_ASSERT (sindx > 0);
2483 outrel.r_info = ELF64_R_INFO (sindx, r_type);
2484 outrel.r_addend = relocation + rel->r_addend;
2488 sreloc = elf_section_data (input_section)->sreloc;
2489 if (sreloc == NULL)
2490 abort ();
2492 loc = sreloc->contents;
2493 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
2494 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2496 /* If this reloc is against an external symbol, we do
2497 not want to fiddle with the addend. Otherwise, we
2498 need to include the symbol value so that it becomes
2499 an addend for the dynamic reloc. */
2500 if (! relocate)
2501 continue;
2504 break;
2506 case R_X86_64_TLSGD:
2507 case R_X86_64_GOTPC32_TLSDESC:
2508 case R_X86_64_TLSDESC_CALL:
2509 case R_X86_64_GOTTPOFF:
2510 r_type = elf64_x86_64_tls_transition (info, r_type, h == NULL);
2511 tls_type = GOT_UNKNOWN;
2512 if (h == NULL && local_got_offsets)
2513 tls_type = elf64_x86_64_local_got_tls_type (input_bfd) [r_symndx];
2514 else if (h != NULL)
2516 tls_type = elf64_x86_64_hash_entry (h)->tls_type;
2517 if (!info->shared && h->dynindx == -1 && tls_type == GOT_TLS_IE)
2518 r_type = R_X86_64_TPOFF32;
2520 if (r_type == R_X86_64_TLSGD
2521 || r_type == R_X86_64_GOTPC32_TLSDESC
2522 || r_type == R_X86_64_TLSDESC_CALL)
2524 if (tls_type == GOT_TLS_IE)
2525 r_type = R_X86_64_GOTTPOFF;
2528 if (r_type == R_X86_64_TPOFF32)
2530 BFD_ASSERT (! unresolved_reloc);
2531 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
2533 unsigned int i;
2534 static unsigned char tlsgd[8]
2535 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2537 /* GD->LE transition.
2538 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2539 .word 0x6666; rex64; call __tls_get_addr@plt
2540 Change it into:
2541 movq %fs:0, %rax
2542 leaq foo@tpoff(%rax), %rax */
2543 BFD_ASSERT (rel->r_offset >= 4);
2544 for (i = 0; i < 4; i++)
2545 BFD_ASSERT (bfd_get_8 (input_bfd,
2546 contents + rel->r_offset - 4 + i)
2547 == tlsgd[i]);
2548 BFD_ASSERT (rel->r_offset + 12 <= input_section->size);
2549 for (i = 0; i < 4; i++)
2550 BFD_ASSERT (bfd_get_8 (input_bfd,
2551 contents + rel->r_offset + 4 + i)
2552 == tlsgd[i+4]);
2553 BFD_ASSERT (rel + 1 < relend);
2554 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2555 memcpy (contents + rel->r_offset - 4,
2556 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0",
2557 16);
2558 bfd_put_32 (output_bfd, tpoff (info, relocation),
2559 contents + rel->r_offset + 8);
2560 /* Skip R_X86_64_PLT32. */
2561 rel++;
2562 continue;
2564 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTPC32_TLSDESC)
2566 /* GDesc -> LE transition.
2567 It's originally something like:
2568 leaq x@tlsdesc(%rip), %rax
2570 Change it to:
2571 movl $x@tpoff, %rax
2573 Registers other than %rax may be set up here. */
2575 unsigned int val, type, type2;
2576 bfd_vma roff;
2578 /* First, make sure it's a leaq adding rip to a
2579 32-bit offset into any register, although it's
2580 probably almost always going to be rax. */
2581 roff = rel->r_offset;
2582 BFD_ASSERT (roff >= 3);
2583 type = bfd_get_8 (input_bfd, contents + roff - 3);
2584 BFD_ASSERT ((type & 0xfb) == 0x48);
2585 type2 = bfd_get_8 (input_bfd, contents + roff - 2);
2586 BFD_ASSERT (type2 == 0x8d);
2587 val = bfd_get_8 (input_bfd, contents + roff - 1);
2588 BFD_ASSERT ((val & 0xc7) == 0x05);
2589 BFD_ASSERT (roff + 4 <= input_section->size);
2591 /* Now modify the instruction as appropriate. */
2592 bfd_put_8 (output_bfd, 0x48 | ((type >> 2) & 1),
2593 contents + roff - 3);
2594 bfd_put_8 (output_bfd, 0xc7, contents + roff - 2);
2595 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7),
2596 contents + roff - 1);
2597 bfd_put_32 (output_bfd, tpoff (info, relocation),
2598 contents + roff);
2599 continue;
2601 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSDESC_CALL)
2603 /* GDesc -> LE transition.
2604 It's originally:
2605 call *(%rax)
2606 Turn it into:
2607 nop; nop. */
2609 unsigned int val, type;
2610 bfd_vma roff;
2612 /* First, make sure it's a call *(%rax). */
2613 roff = rel->r_offset;
2614 BFD_ASSERT (roff + 2 <= input_section->size);
2615 type = bfd_get_8 (input_bfd, contents + roff);
2616 BFD_ASSERT (type == 0xff);
2617 val = bfd_get_8 (input_bfd, contents + roff + 1);
2618 BFD_ASSERT (val == 0x10);
2620 /* Now modify the instruction as appropriate. Use
2621 xchg %ax,%ax instead of 2 nops. */
2622 bfd_put_8 (output_bfd, 0x66, contents + roff);
2623 bfd_put_8 (output_bfd, 0x90, contents + roff + 1);
2624 continue;
2626 else
2628 unsigned int val, type, reg;
2630 /* IE->LE transition:
2631 Originally it can be one of:
2632 movq foo@gottpoff(%rip), %reg
2633 addq foo@gottpoff(%rip), %reg
2634 We change it into:
2635 movq $foo, %reg
2636 leaq foo(%reg), %reg
2637 addq $foo, %reg. */
2638 BFD_ASSERT (rel->r_offset >= 3);
2639 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 3);
2640 BFD_ASSERT (val == 0x48 || val == 0x4c);
2641 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2642 BFD_ASSERT (type == 0x8b || type == 0x03);
2643 reg = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2644 BFD_ASSERT ((reg & 0xc7) == 5);
2645 reg >>= 3;
2646 BFD_ASSERT (rel->r_offset + 4 <= input_section->size);
2647 if (type == 0x8b)
2649 /* movq */
2650 if (val == 0x4c)
2651 bfd_put_8 (output_bfd, 0x49,
2652 contents + rel->r_offset - 3);
2653 bfd_put_8 (output_bfd, 0xc7,
2654 contents + rel->r_offset - 2);
2655 bfd_put_8 (output_bfd, 0xc0 | reg,
2656 contents + rel->r_offset - 1);
2658 else if (reg == 4)
2660 /* addq -> addq - addressing with %rsp/%r12 is
2661 special */
2662 if (val == 0x4c)
2663 bfd_put_8 (output_bfd, 0x49,
2664 contents + rel->r_offset - 3);
2665 bfd_put_8 (output_bfd, 0x81,
2666 contents + rel->r_offset - 2);
2667 bfd_put_8 (output_bfd, 0xc0 | reg,
2668 contents + rel->r_offset - 1);
2670 else
2672 /* addq -> leaq */
2673 if (val == 0x4c)
2674 bfd_put_8 (output_bfd, 0x4d,
2675 contents + rel->r_offset - 3);
2676 bfd_put_8 (output_bfd, 0x8d,
2677 contents + rel->r_offset - 2);
2678 bfd_put_8 (output_bfd, 0x80 | reg | (reg << 3),
2679 contents + rel->r_offset - 1);
2681 bfd_put_32 (output_bfd, tpoff (info, relocation),
2682 contents + rel->r_offset);
2683 continue;
2687 if (htab->sgot == NULL)
2688 abort ();
2690 if (h != NULL)
2692 off = h->got.offset;
2693 offplt = elf64_x86_64_hash_entry (h)->tlsdesc_got;
2695 else
2697 if (local_got_offsets == NULL)
2698 abort ();
2700 off = local_got_offsets[r_symndx];
2701 offplt = local_tlsdesc_gotents[r_symndx];
2704 if ((off & 1) != 0)
2705 off &= ~1;
2706 else
2708 Elf_Internal_Rela outrel;
2709 bfd_byte *loc;
2710 int dr_type, indx;
2711 asection *sreloc;
2713 if (htab->srelgot == NULL)
2714 abort ();
2716 indx = h && h->dynindx != -1 ? h->dynindx : 0;
2718 if (GOT_TLS_GDESC_P (tls_type))
2720 outrel.r_info = ELF64_R_INFO (indx, R_X86_64_TLSDESC);
2721 BFD_ASSERT (htab->sgotplt_jump_table_size + offplt
2722 + 2 * GOT_ENTRY_SIZE <= htab->sgotplt->size);
2723 outrel.r_offset = (htab->sgotplt->output_section->vma
2724 + htab->sgotplt->output_offset
2725 + offplt
2726 + htab->sgotplt_jump_table_size);
2727 sreloc = htab->srelplt;
2728 loc = sreloc->contents;
2729 loc += sreloc->reloc_count++
2730 * sizeof (Elf64_External_Rela);
2731 BFD_ASSERT (loc + sizeof (Elf64_External_Rela)
2732 <= sreloc->contents + sreloc->size);
2733 if (indx == 0)
2734 outrel.r_addend = relocation - dtpoff_base (info);
2735 else
2736 outrel.r_addend = 0;
2737 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2740 sreloc = htab->srelgot;
2742 outrel.r_offset = (htab->sgot->output_section->vma
2743 + htab->sgot->output_offset + off);
2745 if (GOT_TLS_GD_P (tls_type))
2746 dr_type = R_X86_64_DTPMOD64;
2747 else if (GOT_TLS_GDESC_P (tls_type))
2748 goto dr_done;
2749 else
2750 dr_type = R_X86_64_TPOFF64;
2752 bfd_put_64 (output_bfd, 0, htab->sgot->contents + off);
2753 outrel.r_addend = 0;
2754 if ((dr_type == R_X86_64_TPOFF64
2755 || dr_type == R_X86_64_TLSDESC) && indx == 0)
2756 outrel.r_addend = relocation - dtpoff_base (info);
2757 outrel.r_info = ELF64_R_INFO (indx, dr_type);
2759 loc = sreloc->contents;
2760 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
2761 BFD_ASSERT (loc + sizeof (Elf64_External_Rela)
2762 <= sreloc->contents + sreloc->size);
2763 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2765 if (GOT_TLS_GD_P (tls_type))
2767 if (indx == 0)
2769 BFD_ASSERT (! unresolved_reloc);
2770 bfd_put_64 (output_bfd,
2771 relocation - dtpoff_base (info),
2772 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2774 else
2776 bfd_put_64 (output_bfd, 0,
2777 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2778 outrel.r_info = ELF64_R_INFO (indx,
2779 R_X86_64_DTPOFF64);
2780 outrel.r_offset += GOT_ENTRY_SIZE;
2781 sreloc->reloc_count++;
2782 loc += sizeof (Elf64_External_Rela);
2783 BFD_ASSERT (loc + sizeof (Elf64_External_Rela)
2784 <= sreloc->contents + sreloc->size);
2785 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2789 dr_done:
2790 if (h != NULL)
2791 h->got.offset |= 1;
2792 else
2793 local_got_offsets[r_symndx] |= 1;
2796 if (off >= (bfd_vma) -2
2797 && ! GOT_TLS_GDESC_P (tls_type))
2798 abort ();
2799 if (r_type == ELF64_R_TYPE (rel->r_info))
2801 if (r_type == R_X86_64_GOTPC32_TLSDESC
2802 || r_type == R_X86_64_TLSDESC_CALL)
2803 relocation = htab->sgotplt->output_section->vma
2804 + htab->sgotplt->output_offset
2805 + offplt + htab->sgotplt_jump_table_size;
2806 else
2807 relocation = htab->sgot->output_section->vma
2808 + htab->sgot->output_offset + off;
2809 unresolved_reloc = FALSE;
2811 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
2813 unsigned int i;
2814 static unsigned char tlsgd[8]
2815 = { 0x66, 0x48, 0x8d, 0x3d, 0x66, 0x66, 0x48, 0xe8 };
2817 /* GD->IE transition.
2818 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
2819 .word 0x6666; rex64; call __tls_get_addr@plt
2820 Change it into:
2821 movq %fs:0, %rax
2822 addq foo@gottpoff(%rip), %rax */
2823 BFD_ASSERT (rel->r_offset >= 4);
2824 for (i = 0; i < 4; i++)
2825 BFD_ASSERT (bfd_get_8 (input_bfd,
2826 contents + rel->r_offset - 4 + i)
2827 == tlsgd[i]);
2828 BFD_ASSERT (rel->r_offset + 12 <= input_section->size);
2829 for (i = 0; i < 4; i++)
2830 BFD_ASSERT (bfd_get_8 (input_bfd,
2831 contents + rel->r_offset + 4 + i)
2832 == tlsgd[i+4]);
2833 BFD_ASSERT (rel + 1 < relend);
2834 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2835 memcpy (contents + rel->r_offset - 4,
2836 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0",
2837 16);
2839 relocation = (htab->sgot->output_section->vma
2840 + htab->sgot->output_offset + off
2841 - rel->r_offset
2842 - input_section->output_section->vma
2843 - input_section->output_offset
2844 - 12);
2845 bfd_put_32 (output_bfd, relocation,
2846 contents + rel->r_offset + 8);
2847 /* Skip R_X86_64_PLT32. */
2848 rel++;
2849 continue;
2851 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTPC32_TLSDESC)
2853 /* GDesc -> IE transition.
2854 It's originally something like:
2855 leaq x@tlsdesc(%rip), %rax
2857 Change it to:
2858 movq x@gottpoff(%rip), %rax # before nop; nop
2860 Registers other than %rax may be set up here. */
2862 unsigned int val, type, type2;
2863 bfd_vma roff;
2865 /* First, make sure it's a leaq adding rip to a 32-bit
2866 offset into any register, although it's probably
2867 almost always going to be rax. */
2868 roff = rel->r_offset;
2869 BFD_ASSERT (roff >= 3);
2870 type = bfd_get_8 (input_bfd, contents + roff - 3);
2871 BFD_ASSERT ((type & 0xfb) == 0x48);
2872 type2 = bfd_get_8 (input_bfd, contents + roff - 2);
2873 BFD_ASSERT (type2 == 0x8d);
2874 val = bfd_get_8 (input_bfd, contents + roff - 1);
2875 BFD_ASSERT ((val & 0xc7) == 0x05);
2876 BFD_ASSERT (roff + 4 <= input_section->size);
2878 /* Now modify the instruction as appropriate. */
2879 /* To turn a leaq into a movq in the form we use it, it
2880 suffices to change the second byte from 0x8d to
2881 0x8b. */
2882 bfd_put_8 (output_bfd, 0x8b, contents + roff - 2);
2884 bfd_put_32 (output_bfd,
2885 htab->sgot->output_section->vma
2886 + htab->sgot->output_offset + off
2887 - rel->r_offset
2888 - input_section->output_section->vma
2889 - input_section->output_offset
2890 - 4,
2891 contents + roff);
2892 continue;
2894 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSDESC_CALL)
2896 /* GDesc -> IE transition.
2897 It's originally:
2898 call *(%rax)
2900 Change it to:
2901 nop; nop. */
2903 unsigned int val, type;
2904 bfd_vma roff;
2906 /* First, make sure it's a call *(%eax). */
2907 roff = rel->r_offset;
2908 BFD_ASSERT (roff + 2 <= input_section->size);
2909 type = bfd_get_8 (input_bfd, contents + roff);
2910 BFD_ASSERT (type == 0xff);
2911 val = bfd_get_8 (input_bfd, contents + roff + 1);
2912 BFD_ASSERT (val == 0x10);
2914 /* Now modify the instruction as appropriate. Use
2915 xchg %ax,%ax instead of 2 nops. */
2916 bfd_put_8 (output_bfd, 0x66, contents + roff);
2917 bfd_put_8 (output_bfd, 0x90, contents + roff + 1);
2919 continue;
2921 else
2922 BFD_ASSERT (FALSE);
2923 break;
2925 case R_X86_64_TLSLD:
2926 if (! info->shared)
2928 /* LD->LE transition:
2929 Ensure it is:
2930 leaq foo@tlsld(%rip), %rdi; call __tls_get_addr@plt.
2931 We change it into:
2932 .word 0x6666; .byte 0x66; movl %fs:0, %rax. */
2933 BFD_ASSERT (rel->r_offset >= 3);
2934 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 3)
2935 == 0x48);
2936 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 2)
2937 == 0x8d);
2938 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 1)
2939 == 0x3d);
2940 BFD_ASSERT (rel->r_offset + 9 <= input_section->size);
2941 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2942 == 0xe8);
2943 BFD_ASSERT (rel + 1 < relend);
2944 BFD_ASSERT (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32);
2945 memcpy (contents + rel->r_offset - 3,
2946 "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0", 12);
2947 /* Skip R_X86_64_PLT32. */
2948 rel++;
2949 continue;
2952 if (htab->sgot == NULL)
2953 abort ();
2955 off = htab->tls_ld_got.offset;
2956 if (off & 1)
2957 off &= ~1;
2958 else
2960 Elf_Internal_Rela outrel;
2961 bfd_byte *loc;
2963 if (htab->srelgot == NULL)
2964 abort ();
2966 outrel.r_offset = (htab->sgot->output_section->vma
2967 + htab->sgot->output_offset + off);
2969 bfd_put_64 (output_bfd, 0,
2970 htab->sgot->contents + off);
2971 bfd_put_64 (output_bfd, 0,
2972 htab->sgot->contents + off + GOT_ENTRY_SIZE);
2973 outrel.r_info = ELF64_R_INFO (0, R_X86_64_DTPMOD64);
2974 outrel.r_addend = 0;
2975 loc = htab->srelgot->contents;
2976 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
2977 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2978 htab->tls_ld_got.offset |= 1;
2980 relocation = htab->sgot->output_section->vma
2981 + htab->sgot->output_offset + off;
2982 unresolved_reloc = FALSE;
2983 break;
2985 case R_X86_64_DTPOFF32:
2986 if (info->shared || (input_section->flags & SEC_CODE) == 0)
2987 relocation -= dtpoff_base (info);
2988 else
2989 relocation = tpoff (info, relocation);
2990 break;
2992 case R_X86_64_TPOFF32:
2993 BFD_ASSERT (! info->shared);
2994 relocation = tpoff (info, relocation);
2995 break;
2997 default:
2998 break;
3001 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
3002 because such sections are not SEC_ALLOC and thus ld.so will
3003 not process them. */
3004 if (unresolved_reloc
3005 && !((input_section->flags & SEC_DEBUGGING) != 0
3006 && h->def_dynamic))
3007 (*_bfd_error_handler)
3008 (_("%B(%A+0x%lx): unresolvable %s relocation against symbol `%s'"),
3009 input_bfd,
3010 input_section,
3011 (long) rel->r_offset,
3012 howto->name,
3013 h->root.root.string);
3015 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
3016 contents, rel->r_offset,
3017 relocation, rel->r_addend);
3019 if (r != bfd_reloc_ok)
3021 const char *name;
3023 if (h != NULL)
3024 name = h->root.root.string;
3025 else
3027 name = bfd_elf_string_from_elf_section (input_bfd,
3028 symtab_hdr->sh_link,
3029 sym->st_name);
3030 if (name == NULL)
3031 return FALSE;
3032 if (*name == '\0')
3033 name = bfd_section_name (input_bfd, sec);
3036 if (r == bfd_reloc_overflow)
3038 if (h != NULL
3039 && h->root.type == bfd_link_hash_undefweak
3040 && howto->pc_relative)
3041 /* Ignore reloc overflow on branches to undefweak syms. */
3042 continue;
3044 if (! ((*info->callbacks->reloc_overflow)
3045 (info, (h ? &h->root : NULL), name, howto->name,
3046 (bfd_vma) 0, input_bfd, input_section,
3047 rel->r_offset)))
3048 return FALSE;
3050 else
3052 (*_bfd_error_handler)
3053 (_("%B(%A+0x%lx): reloc against `%s': error %d"),
3054 input_bfd, input_section,
3055 (long) rel->r_offset, name, (int) r);
3056 return FALSE;
3061 return TRUE;
3064 /* Finish up dynamic symbol handling. We set the contents of various
3065 dynamic sections here. */
3067 static bfd_boolean
3068 elf64_x86_64_finish_dynamic_symbol (bfd *output_bfd,
3069 struct bfd_link_info *info,
3070 struct elf_link_hash_entry *h,
3071 Elf_Internal_Sym *sym)
3073 struct elf64_x86_64_link_hash_table *htab;
3075 htab = elf64_x86_64_hash_table (info);
3077 if (h->plt.offset != (bfd_vma) -1)
3079 bfd_vma plt_index;
3080 bfd_vma got_offset;
3081 Elf_Internal_Rela rela;
3082 bfd_byte *loc;
3084 /* This symbol has an entry in the procedure linkage table. Set
3085 it up. */
3086 if (h->dynindx == -1
3087 || htab->splt == NULL
3088 || htab->sgotplt == NULL
3089 || htab->srelplt == NULL)
3090 abort ();
3092 /* Get the index in the procedure linkage table which
3093 corresponds to this symbol. This is the index of this symbol
3094 in all the symbols for which we are making plt entries. The
3095 first entry in the procedure linkage table is reserved. */
3096 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
3098 /* Get the offset into the .got table of the entry that
3099 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
3100 bytes. The first three are reserved for the dynamic linker. */
3101 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
3103 /* Fill in the entry in the procedure linkage table. */
3104 memcpy (htab->splt->contents + h->plt.offset, elf64_x86_64_plt_entry,
3105 PLT_ENTRY_SIZE);
3107 /* Insert the relocation positions of the plt section. The magic
3108 numbers at the end of the statements are the positions of the
3109 relocations in the plt section. */
3110 /* Put offset for jmp *name@GOTPCREL(%rip), since the
3111 instruction uses 6 bytes, subtract this value. */
3112 bfd_put_32 (output_bfd,
3113 (htab->sgotplt->output_section->vma
3114 + htab->sgotplt->output_offset
3115 + got_offset
3116 - htab->splt->output_section->vma
3117 - htab->splt->output_offset
3118 - h->plt.offset
3119 - 6),
3120 htab->splt->contents + h->plt.offset + 2);
3121 /* Put relocation index. */
3122 bfd_put_32 (output_bfd, plt_index,
3123 htab->splt->contents + h->plt.offset + 7);
3124 /* Put offset for jmp .PLT0. */
3125 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
3126 htab->splt->contents + h->plt.offset + 12);
3128 /* Fill in the entry in the global offset table, initially this
3129 points to the pushq instruction in the PLT which is at offset 6. */
3130 bfd_put_64 (output_bfd, (htab->splt->output_section->vma
3131 + htab->splt->output_offset
3132 + h->plt.offset + 6),
3133 htab->sgotplt->contents + got_offset);
3135 /* Fill in the entry in the .rela.plt section. */
3136 rela.r_offset = (htab->sgotplt->output_section->vma
3137 + htab->sgotplt->output_offset
3138 + got_offset);
3139 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
3140 rela.r_addend = 0;
3141 loc = htab->srelplt->contents + plt_index * sizeof (Elf64_External_Rela);
3142 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
3144 if (!h->def_regular)
3146 /* Mark the symbol as undefined, rather than as defined in
3147 the .plt section. Leave the value if there were any
3148 relocations where pointer equality matters (this is a clue
3149 for the dynamic linker, to make function pointer
3150 comparisons work between an application and shared
3151 library), otherwise set it to zero. If a function is only
3152 called from a binary, there is no need to slow down
3153 shared libraries because of that. */
3154 sym->st_shndx = SHN_UNDEF;
3155 if (!h->pointer_equality_needed)
3156 sym->st_value = 0;
3160 if (h->got.offset != (bfd_vma) -1
3161 && ! GOT_TLS_GD_ANY_P (elf64_x86_64_hash_entry (h)->tls_type)
3162 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE)
3164 Elf_Internal_Rela rela;
3165 bfd_byte *loc;
3167 /* This symbol has an entry in the global offset table. Set it
3168 up. */
3169 if (htab->sgot == NULL || htab->srelgot == NULL)
3170 abort ();
3172 rela.r_offset = (htab->sgot->output_section->vma
3173 + htab->sgot->output_offset
3174 + (h->got.offset &~ (bfd_vma) 1));
3176 /* If this is a static link, or it is a -Bsymbolic link and the
3177 symbol is defined locally or was forced to be local because
3178 of a version file, we just want to emit a RELATIVE reloc.
3179 The entry in the global offset table will already have been
3180 initialized in the relocate_section function. */
3181 if (info->shared
3182 && SYMBOL_REFERENCES_LOCAL (info, h))
3184 BFD_ASSERT((h->got.offset & 1) != 0);
3185 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
3186 rela.r_addend = (h->root.u.def.value
3187 + h->root.u.def.section->output_section->vma
3188 + h->root.u.def.section->output_offset);
3190 else
3192 BFD_ASSERT((h->got.offset & 1) == 0);
3193 bfd_put_64 (output_bfd, (bfd_vma) 0,
3194 htab->sgot->contents + h->got.offset);
3195 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
3196 rela.r_addend = 0;
3199 loc = htab->srelgot->contents;
3200 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
3201 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
3204 if (h->needs_copy)
3206 Elf_Internal_Rela rela;
3207 bfd_byte *loc;
3209 /* This symbol needs a copy reloc. Set it up. */
3211 if (h->dynindx == -1
3212 || (h->root.type != bfd_link_hash_defined
3213 && h->root.type != bfd_link_hash_defweak)
3214 || htab->srelbss == NULL)
3215 abort ();
3217 rela.r_offset = (h->root.u.def.value
3218 + h->root.u.def.section->output_section->vma
3219 + h->root.u.def.section->output_offset);
3220 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
3221 rela.r_addend = 0;
3222 loc = htab->srelbss->contents;
3223 loc += htab->srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
3224 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
3227 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
3228 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
3229 || h == htab->elf.hgot)
3230 sym->st_shndx = SHN_ABS;
3232 return TRUE;
3235 /* Used to decide how to sort relocs in an optimal manner for the
3236 dynamic linker, before writing them out. */
3238 static enum elf_reloc_type_class
3239 elf64_x86_64_reloc_type_class (const Elf_Internal_Rela *rela)
3241 switch ((int) ELF64_R_TYPE (rela->r_info))
3243 case R_X86_64_RELATIVE:
3244 return reloc_class_relative;
3245 case R_X86_64_JUMP_SLOT:
3246 return reloc_class_plt;
3247 case R_X86_64_COPY:
3248 return reloc_class_copy;
3249 default:
3250 return reloc_class_normal;
3254 /* Finish up the dynamic sections. */
3256 static bfd_boolean
3257 elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
3259 struct elf64_x86_64_link_hash_table *htab;
3260 bfd *dynobj;
3261 asection *sdyn;
3263 htab = elf64_x86_64_hash_table (info);
3264 dynobj = htab->elf.dynobj;
3265 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3267 if (htab->elf.dynamic_sections_created)
3269 Elf64_External_Dyn *dyncon, *dynconend;
3271 if (sdyn == NULL || htab->sgot == NULL)
3272 abort ();
3274 dyncon = (Elf64_External_Dyn *) sdyn->contents;
3275 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->size);
3276 for (; dyncon < dynconend; dyncon++)
3278 Elf_Internal_Dyn dyn;
3279 asection *s;
3281 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
3283 switch (dyn.d_tag)
3285 default:
3286 continue;
3288 case DT_PLTGOT:
3289 s = htab->sgotplt;
3290 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
3291 break;
3293 case DT_JMPREL:
3294 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
3295 break;
3297 case DT_PLTRELSZ:
3298 s = htab->srelplt->output_section;
3299 dyn.d_un.d_val = s->size;
3300 break;
3302 case DT_RELASZ:
3303 /* The procedure linkage table relocs (DT_JMPREL) should
3304 not be included in the overall relocs (DT_RELA).
3305 Therefore, we override the DT_RELASZ entry here to
3306 make it not include the JMPREL relocs. Since the
3307 linker script arranges for .rela.plt to follow all
3308 other relocation sections, we don't have to worry
3309 about changing the DT_RELA entry. */
3310 if (htab->srelplt != NULL)
3312 s = htab->srelplt->output_section;
3313 dyn.d_un.d_val -= s->size;
3315 break;
3317 case DT_TLSDESC_PLT:
3318 s = htab->splt;
3319 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset
3320 + htab->tlsdesc_plt;
3321 break;
3323 case DT_TLSDESC_GOT:
3324 s = htab->sgot;
3325 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset
3326 + htab->tlsdesc_got;
3327 break;
3330 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
3333 /* Fill in the special first entry in the procedure linkage table. */
3334 if (htab->splt && htab->splt->size > 0)
3336 /* Fill in the first entry in the procedure linkage table. */
3337 memcpy (htab->splt->contents, elf64_x86_64_plt0_entry,
3338 PLT_ENTRY_SIZE);
3339 /* Add offset for pushq GOT+8(%rip), since the instruction
3340 uses 6 bytes subtract this value. */
3341 bfd_put_32 (output_bfd,
3342 (htab->sgotplt->output_section->vma
3343 + htab->sgotplt->output_offset
3345 - htab->splt->output_section->vma
3346 - htab->splt->output_offset
3347 - 6),
3348 htab->splt->contents + 2);
3349 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
3350 the end of the instruction. */
3351 bfd_put_32 (output_bfd,
3352 (htab->sgotplt->output_section->vma
3353 + htab->sgotplt->output_offset
3354 + 16
3355 - htab->splt->output_section->vma
3356 - htab->splt->output_offset
3357 - 12),
3358 htab->splt->contents + 8);
3360 elf_section_data (htab->splt->output_section)->this_hdr.sh_entsize =
3361 PLT_ENTRY_SIZE;
3363 if (htab->tlsdesc_plt)
3365 bfd_put_64 (output_bfd, (bfd_vma) 0,
3366 htab->sgot->contents + htab->tlsdesc_got);
3368 memcpy (htab->splt->contents + htab->tlsdesc_plt,
3369 elf64_x86_64_plt0_entry,
3370 PLT_ENTRY_SIZE);
3372 /* Add offset for pushq GOT+8(%rip), since the
3373 instruction uses 6 bytes subtract this value. */
3374 bfd_put_32 (output_bfd,
3375 (htab->sgotplt->output_section->vma
3376 + htab->sgotplt->output_offset
3378 - htab->splt->output_section->vma
3379 - htab->splt->output_offset
3380 - htab->tlsdesc_plt
3381 - 6),
3382 htab->splt->contents + htab->tlsdesc_plt + 2);
3383 /* Add offset for jmp *GOT+TDG(%rip), where TGD stands for
3384 htab->tlsdesc_got. The 12 is the offset to the end of
3385 the instruction. */
3386 bfd_put_32 (output_bfd,
3387 (htab->sgot->output_section->vma
3388 + htab->sgot->output_offset
3389 + htab->tlsdesc_got
3390 - htab->splt->output_section->vma
3391 - htab->splt->output_offset
3392 - htab->tlsdesc_plt
3393 - 12),
3394 htab->splt->contents + htab->tlsdesc_plt + 8);
3399 if (htab->sgotplt)
3401 /* Fill in the first three entries in the global offset table. */
3402 if (htab->sgotplt->size > 0)
3404 /* Set the first entry in the global offset table to the address of
3405 the dynamic section. */
3406 if (sdyn == NULL)
3407 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents);
3408 else
3409 bfd_put_64 (output_bfd,
3410 sdyn->output_section->vma + sdyn->output_offset,
3411 htab->sgotplt->contents);
3412 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
3413 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE);
3414 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE*2);
3417 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize =
3418 GOT_ENTRY_SIZE;
3421 if (htab->sgot && htab->sgot->size > 0)
3422 elf_section_data (htab->sgot->output_section)->this_hdr.sh_entsize
3423 = GOT_ENTRY_SIZE;
3425 return TRUE;
3428 /* Return address for Ith PLT stub in section PLT, for relocation REL
3429 or (bfd_vma) -1 if it should not be included. */
3431 static bfd_vma
3432 elf64_x86_64_plt_sym_val (bfd_vma i, const asection *plt,
3433 const arelent *rel ATTRIBUTE_UNUSED)
3435 return plt->vma + (i + 1) * PLT_ENTRY_SIZE;
3438 /* Handle an x86-64 specific section when reading an object file. This
3439 is called when elfcode.h finds a section with an unknown type. */
3441 static bfd_boolean
3442 elf64_x86_64_section_from_shdr (bfd *abfd,
3443 Elf_Internal_Shdr *hdr,
3444 const char *name,
3445 int shindex)
3447 if (hdr->sh_type != SHT_X86_64_UNWIND)
3448 return FALSE;
3450 if (! _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex))
3451 return FALSE;
3453 return TRUE;
3456 /* Hook called by the linker routine which adds symbols from an object
3457 file. We use it to put SHN_X86_64_LCOMMON items in .lbss, instead
3458 of .bss. */
3460 static bfd_boolean
3461 elf64_x86_64_add_symbol_hook (bfd *abfd,
3462 struct bfd_link_info *info ATTRIBUTE_UNUSED,
3463 Elf_Internal_Sym *sym,
3464 const char **namep ATTRIBUTE_UNUSED,
3465 flagword *flagsp ATTRIBUTE_UNUSED,
3466 asection **secp, bfd_vma *valp)
3468 asection *lcomm;
3470 switch (sym->st_shndx)
3472 case SHN_X86_64_LCOMMON:
3473 lcomm = bfd_get_section_by_name (abfd, "LARGE_COMMON");
3474 if (lcomm == NULL)
3476 lcomm = bfd_make_section_with_flags (abfd,
3477 "LARGE_COMMON",
3478 (SEC_ALLOC
3479 | SEC_IS_COMMON
3480 | SEC_LINKER_CREATED));
3481 if (lcomm == NULL)
3482 return FALSE;
3483 elf_section_flags (lcomm) |= SHF_X86_64_LARGE;
3485 *secp = lcomm;
3486 *valp = sym->st_size;
3487 break;
3489 return TRUE;
3493 /* Given a BFD section, try to locate the corresponding ELF section
3494 index. */
3496 static bfd_boolean
3497 elf64_x86_64_elf_section_from_bfd_section (bfd *abfd ATTRIBUTE_UNUSED,
3498 asection *sec, int *index)
3500 if (sec == &_bfd_elf_large_com_section)
3502 *index = SHN_X86_64_LCOMMON;
3503 return TRUE;
3505 return FALSE;
3508 /* Process a symbol. */
3510 static void
3511 elf64_x86_64_symbol_processing (bfd *abfd ATTRIBUTE_UNUSED,
3512 asymbol *asym)
3514 elf_symbol_type *elfsym = (elf_symbol_type *) asym;
3516 switch (elfsym->internal_elf_sym.st_shndx)
3518 case SHN_X86_64_LCOMMON:
3519 asym->section = &_bfd_elf_large_com_section;
3520 asym->value = elfsym->internal_elf_sym.st_size;
3521 /* Common symbol doesn't set BSF_GLOBAL. */
3522 asym->flags &= ~BSF_GLOBAL;
3523 break;
3527 static bfd_boolean
3528 elf64_x86_64_common_definition (Elf_Internal_Sym *sym)
3530 return (sym->st_shndx == SHN_COMMON
3531 || sym->st_shndx == SHN_X86_64_LCOMMON);
3534 static unsigned int
3535 elf64_x86_64_common_section_index (asection *sec)
3537 if ((elf_section_flags (sec) & SHF_X86_64_LARGE) == 0)
3538 return SHN_COMMON;
3539 else
3540 return SHN_X86_64_LCOMMON;
3543 static asection *
3544 elf64_x86_64_common_section (asection *sec)
3546 if ((elf_section_flags (sec) & SHF_X86_64_LARGE) == 0)
3547 return bfd_com_section_ptr;
3548 else
3549 return &_bfd_elf_large_com_section;
3552 static bfd_boolean
3553 elf64_x86_64_merge_symbol (struct bfd_link_info *info ATTRIBUTE_UNUSED,
3554 struct elf_link_hash_entry **sym_hash ATTRIBUTE_UNUSED,
3555 struct elf_link_hash_entry *h,
3556 Elf_Internal_Sym *sym,
3557 asection **psec,
3558 bfd_vma *pvalue ATTRIBUTE_UNUSED,
3559 unsigned int *pold_alignment ATTRIBUTE_UNUSED,
3560 bfd_boolean *skip ATTRIBUTE_UNUSED,
3561 bfd_boolean *override ATTRIBUTE_UNUSED,
3562 bfd_boolean *type_change_ok ATTRIBUTE_UNUSED,
3563 bfd_boolean *size_change_ok ATTRIBUTE_UNUSED,
3564 bfd_boolean *newdef ATTRIBUTE_UNUSED,
3565 bfd_boolean *newdyn,
3566 bfd_boolean *newdyncommon ATTRIBUTE_UNUSED,
3567 bfd_boolean *newweak ATTRIBUTE_UNUSED,
3568 bfd *abfd ATTRIBUTE_UNUSED,
3569 asection **sec,
3570 bfd_boolean *olddef ATTRIBUTE_UNUSED,
3571 bfd_boolean *olddyn,
3572 bfd_boolean *olddyncommon ATTRIBUTE_UNUSED,
3573 bfd_boolean *oldweak ATTRIBUTE_UNUSED,
3574 bfd *oldbfd,
3575 asection **oldsec)
3577 /* A normal common symbol and a large common symbol result in a
3578 normal common symbol. We turn the large common symbol into a
3579 normal one. */
3580 if (!*olddyn
3581 && h->root.type == bfd_link_hash_common
3582 && !*newdyn
3583 && bfd_is_com_section (*sec)
3584 && *oldsec != *sec)
3586 if (sym->st_shndx == SHN_COMMON
3587 && (elf_section_flags (*oldsec) & SHF_X86_64_LARGE) != 0)
3589 h->root.u.c.p->section
3590 = bfd_make_section_old_way (oldbfd, "COMMON");
3591 h->root.u.c.p->section->flags = SEC_ALLOC;
3593 else if (sym->st_shndx == SHN_X86_64_LCOMMON
3594 && (elf_section_flags (*oldsec) & SHF_X86_64_LARGE) == 0)
3595 *psec = *sec = bfd_com_section_ptr;
3598 return TRUE;
3601 static int
3602 elf64_x86_64_additional_program_headers (bfd *abfd,
3603 struct bfd_link_info *info ATTRIBUTE_UNUSED)
3605 asection *s;
3606 int count = 0;
3608 /* Check to see if we need a large readonly segment. */
3609 s = bfd_get_section_by_name (abfd, ".lrodata");
3610 if (s && (s->flags & SEC_LOAD))
3611 count++;
3613 /* Check to see if we need a large data segment. Since .lbss sections
3614 is placed right after the .bss section, there should be no need for
3615 a large data segment just because of .lbss. */
3616 s = bfd_get_section_by_name (abfd, ".ldata");
3617 if (s && (s->flags & SEC_LOAD))
3618 count++;
3620 return count;
3623 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
3625 static bfd_boolean
3626 elf64_x86_64_hash_symbol (struct elf_link_hash_entry *h)
3628 if (h->plt.offset != (bfd_vma) -1
3629 && !h->def_regular
3630 && !h->pointer_equality_needed)
3631 return FALSE;
3633 return _bfd_elf_hash_symbol (h);
3636 static const struct bfd_elf_special_section
3637 elf64_x86_64_special_sections[]=
3639 { ".gnu.linkonce.lb", 16, -2, SHT_NOBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE},
3640 { ".gnu.linkonce.lr", 16, -2, SHT_PROGBITS, SHF_ALLOC + SHF_X86_64_LARGE},
3641 { ".gnu.linkonce.lt", 16, -2, SHT_PROGBITS, SHF_ALLOC + SHF_EXECINSTR + SHF_X86_64_LARGE},
3642 { ".lbss", 5, -2, SHT_NOBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE},
3643 { ".ldata", 6, -2, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE},
3644 { ".lrodata", 8, -2, SHT_PROGBITS, SHF_ALLOC + SHF_X86_64_LARGE},
3645 { NULL, 0, 0, 0, 0 }
3648 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
3649 #define TARGET_LITTLE_NAME "elf64-x86-64"
3650 #define ELF_ARCH bfd_arch_i386
3651 #define ELF_MACHINE_CODE EM_X86_64
3652 #define ELF_MAXPAGESIZE 0x200000
3653 #define ELF_MINPAGESIZE 0x1000
3654 #define ELF_COMMONPAGESIZE 0x1000
3656 #define elf_backend_can_gc_sections 1
3657 #define elf_backend_can_refcount 1
3658 #define elf_backend_want_got_plt 1
3659 #define elf_backend_plt_readonly 1
3660 #define elf_backend_want_plt_sym 0
3661 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
3662 #define elf_backend_rela_normal 1
3664 #define elf_info_to_howto elf64_x86_64_info_to_howto
3666 #define bfd_elf64_bfd_link_hash_table_create \
3667 elf64_x86_64_link_hash_table_create
3668 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
3670 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
3671 #define elf_backend_check_relocs elf64_x86_64_check_relocs
3672 #define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol
3673 #define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections
3674 #define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections
3675 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
3676 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
3677 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
3678 #define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus
3679 #define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo
3680 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
3681 #define elf_backend_relocate_section elf64_x86_64_relocate_section
3682 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
3683 #define elf_backend_always_size_sections elf64_x86_64_always_size_sections
3684 #define elf_backend_plt_sym_val elf64_x86_64_plt_sym_val
3685 #define elf_backend_object_p elf64_x86_64_elf_object_p
3686 #define bfd_elf64_mkobject elf64_x86_64_mkobject
3688 #define elf_backend_section_from_shdr \
3689 elf64_x86_64_section_from_shdr
3691 #define elf_backend_section_from_bfd_section \
3692 elf64_x86_64_elf_section_from_bfd_section
3693 #define elf_backend_add_symbol_hook \
3694 elf64_x86_64_add_symbol_hook
3695 #define elf_backend_symbol_processing \
3696 elf64_x86_64_symbol_processing
3697 #define elf_backend_common_section_index \
3698 elf64_x86_64_common_section_index
3699 #define elf_backend_common_section \
3700 elf64_x86_64_common_section
3701 #define elf_backend_common_definition \
3702 elf64_x86_64_common_definition
3703 #define elf_backend_merge_symbol \
3704 elf64_x86_64_merge_symbol
3705 #define elf_backend_special_sections \
3706 elf64_x86_64_special_sections
3707 #define elf_backend_additional_program_headers \
3708 elf64_x86_64_additional_program_headers
3709 #define elf_backend_hash_symbol \
3710 elf64_x86_64_hash_symbol
3712 #include "elf64-target.h"