binutils/
[binutils.git] / bfd / elf64-x86-64.c
blob4fb325a9b0ee36e06dce3a8e224e1009745c4c56
1 /* X86-64 specific support for 64-bit ELF
2 Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
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 3 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,
21 MA 02110-1301, USA. */
23 #include "sysdep.h"
24 #include "bfd.h"
25 #include "bfdlink.h"
26 #include "libbfd.h"
27 #include "elf-bfd.h"
28 #include "bfd_stdint.h"
29 #include "objalloc.h"
30 #include "hashtab.h"
32 #include "elf/x86-64.h"
34 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
35 #define MINUS_ONE (~ (bfd_vma) 0)
37 /* The relocation "howto" table. Order of fields:
38 type, rightshift, size, bitsize, pc_relative, bitpos, complain_on_overflow,
39 special_function, name, partial_inplace, src_mask, dst_mask, pcrel_offset. */
40 static reloc_howto_type x86_64_elf_howto_table[] =
42 HOWTO(R_X86_64_NONE, 0, 0, 0, FALSE, 0, complain_overflow_dont,
43 bfd_elf_generic_reloc, "R_X86_64_NONE", FALSE, 0x00000000, 0x00000000,
44 FALSE),
45 HOWTO(R_X86_64_64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
46 bfd_elf_generic_reloc, "R_X86_64_64", FALSE, MINUS_ONE, MINUS_ONE,
47 FALSE),
48 HOWTO(R_X86_64_PC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
49 bfd_elf_generic_reloc, "R_X86_64_PC32", FALSE, 0xffffffff, 0xffffffff,
50 TRUE),
51 HOWTO(R_X86_64_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
52 bfd_elf_generic_reloc, "R_X86_64_GOT32", FALSE, 0xffffffff, 0xffffffff,
53 FALSE),
54 HOWTO(R_X86_64_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
55 bfd_elf_generic_reloc, "R_X86_64_PLT32", FALSE, 0xffffffff, 0xffffffff,
56 TRUE),
57 HOWTO(R_X86_64_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
58 bfd_elf_generic_reloc, "R_X86_64_COPY", FALSE, 0xffffffff, 0xffffffff,
59 FALSE),
60 HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
61 bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", FALSE, MINUS_ONE,
62 MINUS_ONE, FALSE),
63 HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
64 bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", FALSE, MINUS_ONE,
65 MINUS_ONE, FALSE),
66 HOWTO(R_X86_64_RELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
67 bfd_elf_generic_reloc, "R_X86_64_RELATIVE", FALSE, MINUS_ONE,
68 MINUS_ONE, FALSE),
69 HOWTO(R_X86_64_GOTPCREL, 0, 2, 32, TRUE, 0, complain_overflow_signed,
70 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", FALSE, 0xffffffff,
71 0xffffffff, TRUE),
72 HOWTO(R_X86_64_32, 0, 2, 32, FALSE, 0, complain_overflow_unsigned,
73 bfd_elf_generic_reloc, "R_X86_64_32", FALSE, 0xffffffff, 0xffffffff,
74 FALSE),
75 HOWTO(R_X86_64_32S, 0, 2, 32, FALSE, 0, complain_overflow_signed,
76 bfd_elf_generic_reloc, "R_X86_64_32S", FALSE, 0xffffffff, 0xffffffff,
77 FALSE),
78 HOWTO(R_X86_64_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
79 bfd_elf_generic_reloc, "R_X86_64_16", FALSE, 0xffff, 0xffff, FALSE),
80 HOWTO(R_X86_64_PC16,0, 1, 16, TRUE, 0, complain_overflow_bitfield,
81 bfd_elf_generic_reloc, "R_X86_64_PC16", FALSE, 0xffff, 0xffff, TRUE),
82 HOWTO(R_X86_64_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,
83 bfd_elf_generic_reloc, "R_X86_64_8", FALSE, 0xff, 0xff, FALSE),
84 HOWTO(R_X86_64_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed,
85 bfd_elf_generic_reloc, "R_X86_64_PC8", FALSE, 0xff, 0xff, TRUE),
86 HOWTO(R_X86_64_DTPMOD64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
87 bfd_elf_generic_reloc, "R_X86_64_DTPMOD64", FALSE, MINUS_ONE,
88 MINUS_ONE, FALSE),
89 HOWTO(R_X86_64_DTPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
90 bfd_elf_generic_reloc, "R_X86_64_DTPOFF64", FALSE, MINUS_ONE,
91 MINUS_ONE, FALSE),
92 HOWTO(R_X86_64_TPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
93 bfd_elf_generic_reloc, "R_X86_64_TPOFF64", FALSE, MINUS_ONE,
94 MINUS_ONE, FALSE),
95 HOWTO(R_X86_64_TLSGD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
96 bfd_elf_generic_reloc, "R_X86_64_TLSGD", FALSE, 0xffffffff,
97 0xffffffff, TRUE),
98 HOWTO(R_X86_64_TLSLD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
99 bfd_elf_generic_reloc, "R_X86_64_TLSLD", FALSE, 0xffffffff,
100 0xffffffff, TRUE),
101 HOWTO(R_X86_64_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
102 bfd_elf_generic_reloc, "R_X86_64_DTPOFF32", FALSE, 0xffffffff,
103 0xffffffff, FALSE),
104 HOWTO(R_X86_64_GOTTPOFF, 0, 2, 32, TRUE, 0, complain_overflow_signed,
105 bfd_elf_generic_reloc, "R_X86_64_GOTTPOFF", FALSE, 0xffffffff,
106 0xffffffff, TRUE),
107 HOWTO(R_X86_64_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
108 bfd_elf_generic_reloc, "R_X86_64_TPOFF32", FALSE, 0xffffffff,
109 0xffffffff, FALSE),
110 HOWTO(R_X86_64_PC64, 0, 4, 64, TRUE, 0, complain_overflow_bitfield,
111 bfd_elf_generic_reloc, "R_X86_64_PC64", FALSE, MINUS_ONE, MINUS_ONE,
112 TRUE),
113 HOWTO(R_X86_64_GOTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
114 bfd_elf_generic_reloc, "R_X86_64_GOTOFF64",
115 FALSE, MINUS_ONE, MINUS_ONE, FALSE),
116 HOWTO(R_X86_64_GOTPC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
117 bfd_elf_generic_reloc, "R_X86_64_GOTPC32",
118 FALSE, 0xffffffff, 0xffffffff, TRUE),
119 HOWTO(R_X86_64_GOT64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
120 bfd_elf_generic_reloc, "R_X86_64_GOT64", FALSE, MINUS_ONE, MINUS_ONE,
121 FALSE),
122 HOWTO(R_X86_64_GOTPCREL64, 0, 4, 64, TRUE, 0, complain_overflow_signed,
123 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL64", FALSE, MINUS_ONE,
124 MINUS_ONE, TRUE),
125 HOWTO(R_X86_64_GOTPC64, 0, 4, 64, TRUE, 0, complain_overflow_signed,
126 bfd_elf_generic_reloc, "R_X86_64_GOTPC64",
127 FALSE, MINUS_ONE, MINUS_ONE, TRUE),
128 HOWTO(R_X86_64_GOTPLT64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
129 bfd_elf_generic_reloc, "R_X86_64_GOTPLT64", FALSE, MINUS_ONE,
130 MINUS_ONE, FALSE),
131 HOWTO(R_X86_64_PLTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
132 bfd_elf_generic_reloc, "R_X86_64_PLTOFF64", FALSE, MINUS_ONE,
133 MINUS_ONE, FALSE),
134 EMPTY_HOWTO (32),
135 EMPTY_HOWTO (33),
136 HOWTO(R_X86_64_GOTPC32_TLSDESC, 0, 2, 32, TRUE, 0,
137 complain_overflow_bitfield, bfd_elf_generic_reloc,
138 "R_X86_64_GOTPC32_TLSDESC",
139 FALSE, 0xffffffff, 0xffffffff, TRUE),
140 HOWTO(R_X86_64_TLSDESC_CALL, 0, 0, 0, FALSE, 0,
141 complain_overflow_dont, bfd_elf_generic_reloc,
142 "R_X86_64_TLSDESC_CALL",
143 FALSE, 0, 0, FALSE),
144 HOWTO(R_X86_64_TLSDESC, 0, 4, 64, FALSE, 0,
145 complain_overflow_bitfield, bfd_elf_generic_reloc,
146 "R_X86_64_TLSDESC",
147 FALSE, MINUS_ONE, MINUS_ONE, FALSE),
148 HOWTO(R_X86_64_IRELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
149 bfd_elf_generic_reloc, "R_X86_64_IRELATIVE", FALSE, MINUS_ONE,
150 MINUS_ONE, FALSE),
152 /* We have a gap in the reloc numbers here.
153 R_X86_64_standard counts the number up to this point, and
154 R_X86_64_vt_offset is the value to subtract from a reloc type of
155 R_X86_64_GNU_VT* to form an index into this table. */
156 #define R_X86_64_standard (R_X86_64_IRELATIVE + 1)
157 #define R_X86_64_vt_offset (R_X86_64_GNU_VTINHERIT - R_X86_64_standard)
159 /* GNU extension to record C++ vtable hierarchy. */
160 HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, FALSE, 0, complain_overflow_dont,
161 NULL, "R_X86_64_GNU_VTINHERIT", FALSE, 0, 0, FALSE),
163 /* GNU extension to record C++ vtable member usage. */
164 HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, FALSE, 0, complain_overflow_dont,
165 _bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", FALSE, 0, 0,
166 FALSE)
169 #define IS_X86_64_PCREL_TYPE(TYPE) \
170 ( ((TYPE) == R_X86_64_PC8) \
171 || ((TYPE) == R_X86_64_PC16) \
172 || ((TYPE) == R_X86_64_PC32) \
173 || ((TYPE) == R_X86_64_PC64))
175 /* Map BFD relocs to the x86_64 elf relocs. */
176 struct elf_reloc_map
178 bfd_reloc_code_real_type bfd_reloc_val;
179 unsigned char elf_reloc_val;
182 static const struct elf_reloc_map x86_64_reloc_map[] =
184 { BFD_RELOC_NONE, R_X86_64_NONE, },
185 { BFD_RELOC_64, R_X86_64_64, },
186 { BFD_RELOC_32_PCREL, R_X86_64_PC32, },
187 { BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,},
188 { BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,},
189 { BFD_RELOC_X86_64_COPY, R_X86_64_COPY, },
190 { BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, },
191 { BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, },
192 { BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, },
193 { BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, },
194 { BFD_RELOC_32, R_X86_64_32, },
195 { BFD_RELOC_X86_64_32S, R_X86_64_32S, },
196 { BFD_RELOC_16, R_X86_64_16, },
197 { BFD_RELOC_16_PCREL, R_X86_64_PC16, },
198 { BFD_RELOC_8, R_X86_64_8, },
199 { BFD_RELOC_8_PCREL, R_X86_64_PC8, },
200 { BFD_RELOC_X86_64_DTPMOD64, R_X86_64_DTPMOD64, },
201 { BFD_RELOC_X86_64_DTPOFF64, R_X86_64_DTPOFF64, },
202 { BFD_RELOC_X86_64_TPOFF64, R_X86_64_TPOFF64, },
203 { BFD_RELOC_X86_64_TLSGD, R_X86_64_TLSGD, },
204 { BFD_RELOC_X86_64_TLSLD, R_X86_64_TLSLD, },
205 { BFD_RELOC_X86_64_DTPOFF32, R_X86_64_DTPOFF32, },
206 { BFD_RELOC_X86_64_GOTTPOFF, R_X86_64_GOTTPOFF, },
207 { BFD_RELOC_X86_64_TPOFF32, R_X86_64_TPOFF32, },
208 { BFD_RELOC_64_PCREL, R_X86_64_PC64, },
209 { BFD_RELOC_X86_64_GOTOFF64, R_X86_64_GOTOFF64, },
210 { BFD_RELOC_X86_64_GOTPC32, R_X86_64_GOTPC32, },
211 { BFD_RELOC_X86_64_GOT64, R_X86_64_GOT64, },
212 { BFD_RELOC_X86_64_GOTPCREL64,R_X86_64_GOTPCREL64, },
213 { BFD_RELOC_X86_64_GOTPC64, R_X86_64_GOTPC64, },
214 { BFD_RELOC_X86_64_GOTPLT64, R_X86_64_GOTPLT64, },
215 { BFD_RELOC_X86_64_PLTOFF64, R_X86_64_PLTOFF64, },
216 { BFD_RELOC_X86_64_GOTPC32_TLSDESC, R_X86_64_GOTPC32_TLSDESC, },
217 { BFD_RELOC_X86_64_TLSDESC_CALL, R_X86_64_TLSDESC_CALL, },
218 { BFD_RELOC_X86_64_TLSDESC, R_X86_64_TLSDESC, },
219 { BFD_RELOC_X86_64_IRELATIVE, R_X86_64_IRELATIVE, },
220 { BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
221 { BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
224 static reloc_howto_type *
225 elf64_x86_64_rtype_to_howto (bfd *abfd, unsigned r_type)
227 unsigned i;
229 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT
230 || r_type >= (unsigned int) R_X86_64_max)
232 if (r_type >= (unsigned int) R_X86_64_standard)
234 (*_bfd_error_handler) (_("%B: invalid relocation type %d"),
235 abfd, (int) r_type);
236 r_type = R_X86_64_NONE;
238 i = r_type;
240 else
241 i = r_type - (unsigned int) R_X86_64_vt_offset;
242 BFD_ASSERT (x86_64_elf_howto_table[i].type == r_type);
243 return &x86_64_elf_howto_table[i];
246 /* Given a BFD reloc type, return a HOWTO structure. */
247 static reloc_howto_type *
248 elf64_x86_64_reloc_type_lookup (bfd *abfd,
249 bfd_reloc_code_real_type code)
251 unsigned int i;
253 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
254 i++)
256 if (x86_64_reloc_map[i].bfd_reloc_val == code)
257 return elf64_x86_64_rtype_to_howto (abfd,
258 x86_64_reloc_map[i].elf_reloc_val);
260 return 0;
263 static reloc_howto_type *
264 elf64_x86_64_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
265 const char *r_name)
267 unsigned int i;
269 for (i = 0;
270 i < (sizeof (x86_64_elf_howto_table)
271 / sizeof (x86_64_elf_howto_table[0]));
272 i++)
273 if (x86_64_elf_howto_table[i].name != NULL
274 && strcasecmp (x86_64_elf_howto_table[i].name, r_name) == 0)
275 return &x86_64_elf_howto_table[i];
277 return NULL;
280 /* Given an x86_64 ELF reloc type, fill in an arelent structure. */
282 static void
283 elf64_x86_64_info_to_howto (bfd *abfd ATTRIBUTE_UNUSED, arelent *cache_ptr,
284 Elf_Internal_Rela *dst)
286 unsigned r_type;
288 r_type = ELF64_R_TYPE (dst->r_info);
289 cache_ptr->howto = elf64_x86_64_rtype_to_howto (abfd, r_type);
290 BFD_ASSERT (r_type == cache_ptr->howto->type);
293 /* Support for core dump NOTE sections. */
294 static bfd_boolean
295 elf64_x86_64_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
297 int offset;
298 size_t size;
300 switch (note->descsz)
302 default:
303 return FALSE;
305 case 336: /* sizeof(istruct elf_prstatus) on Linux/x86_64 */
306 /* pr_cursig */
307 elf_tdata (abfd)->core_signal
308 = bfd_get_16 (abfd, note->descdata + 12);
310 /* pr_pid */
311 elf_tdata (abfd)->core_pid
312 = bfd_get_32 (abfd, note->descdata + 32);
314 /* pr_reg */
315 offset = 112;
316 size = 216;
318 break;
321 /* Make a ".reg/999" section. */
322 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
323 size, note->descpos + offset);
326 static bfd_boolean
327 elf64_x86_64_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
329 switch (note->descsz)
331 default:
332 return FALSE;
334 case 136: /* sizeof(struct elf_prpsinfo) on Linux/x86_64 */
335 elf_tdata (abfd)->core_program
336 = _bfd_elfcore_strndup (abfd, note->descdata + 40, 16);
337 elf_tdata (abfd)->core_command
338 = _bfd_elfcore_strndup (abfd, note->descdata + 56, 80);
341 /* Note that for some reason, a spurious space is tacked
342 onto the end of the args in some (at least one anyway)
343 implementations, so strip it off if it exists. */
346 char *command = elf_tdata (abfd)->core_command;
347 int n = strlen (command);
349 if (0 < n && command[n - 1] == ' ')
350 command[n - 1] = '\0';
353 return TRUE;
356 /* Functions for the x86-64 ELF linker. */
358 /* The name of the dynamic interpreter. This is put in the .interp
359 section. */
361 #define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
363 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
364 copying dynamic variables from a shared lib into an app's dynbss
365 section, and instead use a dynamic relocation to point into the
366 shared lib. */
367 #define ELIMINATE_COPY_RELOCS 1
369 /* The size in bytes of an entry in the global offset table. */
371 #define GOT_ENTRY_SIZE 8
373 /* The size in bytes of an entry in the procedure linkage table. */
375 #define PLT_ENTRY_SIZE 16
377 /* The first entry in a procedure linkage table looks like this. See the
378 SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
380 static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
382 0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
383 0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
384 0x0f, 0x1f, 0x40, 0x00 /* nopl 0(%rax) */
387 /* Subsequent entries in a procedure linkage table look like this. */
389 static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] =
391 0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
392 0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
393 0x68, /* pushq immediate */
394 0, 0, 0, 0, /* replaced with index into relocation table. */
395 0xe9, /* jmp relative */
396 0, 0, 0, 0 /* replaced with offset to start of .plt0. */
399 /* x86-64 ELF linker hash entry. */
401 struct elf64_x86_64_link_hash_entry
403 struct elf_link_hash_entry elf;
405 /* Track dynamic relocs copied for this symbol. */
406 struct elf_dyn_relocs *dyn_relocs;
408 #define GOT_UNKNOWN 0
409 #define GOT_NORMAL 1
410 #define GOT_TLS_GD 2
411 #define GOT_TLS_IE 3
412 #define GOT_TLS_GDESC 4
413 #define GOT_TLS_GD_BOTH_P(type) \
414 ((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
415 #define GOT_TLS_GD_P(type) \
416 ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
417 #define GOT_TLS_GDESC_P(type) \
418 ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
419 #define GOT_TLS_GD_ANY_P(type) \
420 (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
421 unsigned char tls_type;
423 /* Offset of the GOTPLT entry reserved for the TLS descriptor,
424 starting at the end of the jump table. */
425 bfd_vma tlsdesc_got;
428 #define elf64_x86_64_hash_entry(ent) \
429 ((struct elf64_x86_64_link_hash_entry *)(ent))
431 struct elf64_x86_64_obj_tdata
433 struct elf_obj_tdata root;
435 /* tls_type for each local got entry. */
436 char *local_got_tls_type;
438 /* GOTPLT entries for TLS descriptors. */
439 bfd_vma *local_tlsdesc_gotent;
442 #define elf64_x86_64_tdata(abfd) \
443 ((struct elf64_x86_64_obj_tdata *) (abfd)->tdata.any)
445 #define elf64_x86_64_local_got_tls_type(abfd) \
446 (elf64_x86_64_tdata (abfd)->local_got_tls_type)
448 #define elf64_x86_64_local_tlsdesc_gotent(abfd) \
449 (elf64_x86_64_tdata (abfd)->local_tlsdesc_gotent)
451 #define is_x86_64_elf(bfd) \
452 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \
453 && elf_tdata (bfd) != NULL \
454 && elf_object_id (bfd) == X86_64_ELF_TDATA)
456 static bfd_boolean
457 elf64_x86_64_mkobject (bfd *abfd)
459 return bfd_elf_allocate_object (abfd, sizeof (struct elf64_x86_64_obj_tdata),
460 X86_64_ELF_TDATA);
463 /* x86-64 ELF linker hash table. */
465 struct elf64_x86_64_link_hash_table
467 struct elf_link_hash_table elf;
469 /* Short-cuts to get to dynamic linker sections. */
470 asection *sdynbss;
471 asection *srelbss;
473 /* The offset into splt of the PLT entry for the TLS descriptor
474 resolver. Special values are 0, if not necessary (or not found
475 to be necessary yet), and -1 if needed but not determined
476 yet. */
477 bfd_vma tlsdesc_plt;
478 /* The offset into sgot of the GOT entry used by the PLT entry
479 above. */
480 bfd_vma tlsdesc_got;
482 union {
483 bfd_signed_vma refcount;
484 bfd_vma offset;
485 } tls_ld_got;
487 /* The amount of space used by the jump slots in the GOT. */
488 bfd_vma sgotplt_jump_table_size;
490 /* Small local sym cache. */
491 struct sym_cache sym_cache;
493 /* _TLS_MODULE_BASE_ symbol. */
494 struct bfd_link_hash_entry *tls_module_base;
496 /* Used by local STT_GNU_IFUNC symbols. */
497 htab_t loc_hash_table;
498 void *loc_hash_memory;
501 /* Get the x86-64 ELF linker hash table from a link_info structure. */
503 #define elf64_x86_64_hash_table(p) \
504 ((struct elf64_x86_64_link_hash_table *) ((p)->hash))
506 #define elf64_x86_64_compute_jump_table_size(htab) \
507 ((htab)->elf.srelplt->reloc_count * GOT_ENTRY_SIZE)
509 /* Create an entry in an x86-64 ELF linker hash table. */
511 static struct bfd_hash_entry *
512 elf64_x86_64_link_hash_newfunc (struct bfd_hash_entry *entry,
513 struct bfd_hash_table *table,
514 const char *string)
516 /* Allocate the structure if it has not already been allocated by a
517 subclass. */
518 if (entry == NULL)
520 entry = (struct bfd_hash_entry *)
521 bfd_hash_allocate (table,
522 sizeof (struct elf64_x86_64_link_hash_entry));
523 if (entry == NULL)
524 return entry;
527 /* Call the allocation method of the superclass. */
528 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
529 if (entry != NULL)
531 struct elf64_x86_64_link_hash_entry *eh;
533 eh = (struct elf64_x86_64_link_hash_entry *) entry;
534 eh->dyn_relocs = NULL;
535 eh->tls_type = GOT_UNKNOWN;
536 eh->tlsdesc_got = (bfd_vma) -1;
539 return entry;
542 /* Compute a hash of a local hash entry. We use elf_link_hash_entry
543 for local symbol so that we can handle local STT_GNU_IFUNC symbols
544 as global symbol. We reuse indx and dynstr_index for local symbol
545 hash since they aren't used by global symbols in this backend. */
547 static hashval_t
548 elf64_x86_64_local_htab_hash (const void *ptr)
550 struct elf_link_hash_entry *h
551 = (struct elf_link_hash_entry *) ptr;
552 return ELF_LOCAL_SYMBOL_HASH (h->indx, h->dynstr_index);
555 /* Compare local hash entries. */
557 static int
558 elf64_x86_64_local_htab_eq (const void *ptr1, const void *ptr2)
560 struct elf_link_hash_entry *h1
561 = (struct elf_link_hash_entry *) ptr1;
562 struct elf_link_hash_entry *h2
563 = (struct elf_link_hash_entry *) ptr2;
565 return h1->indx == h2->indx && h1->dynstr_index == h2->dynstr_index;
568 /* Find and/or create a hash entry for local symbol. */
570 static struct elf_link_hash_entry *
571 elf64_x86_64_get_local_sym_hash (struct elf64_x86_64_link_hash_table *htab,
572 bfd *abfd, const Elf_Internal_Rela *rel,
573 bfd_boolean create)
575 struct elf64_x86_64_link_hash_entry e, *ret;
576 asection *sec = abfd->sections;
577 hashval_t h = ELF_LOCAL_SYMBOL_HASH (sec->id,
578 ELF64_R_SYM (rel->r_info));
579 void **slot;
581 e.elf.indx = sec->id;
582 e.elf.dynstr_index = ELF64_R_SYM (rel->r_info);
583 slot = htab_find_slot_with_hash (htab->loc_hash_table, &e, h,
584 create ? INSERT : NO_INSERT);
586 if (!slot)
587 return NULL;
589 if (*slot)
591 ret = (struct elf64_x86_64_link_hash_entry *) *slot;
592 return &ret->elf;
595 ret = (struct elf64_x86_64_link_hash_entry *)
596 objalloc_alloc ((struct objalloc *) htab->loc_hash_memory,
597 sizeof (struct elf64_x86_64_link_hash_entry));
598 if (ret)
600 memset (ret, 0, sizeof (*ret));
601 ret->elf.indx = sec->id;
602 ret->elf.dynstr_index = ELF64_R_SYM (rel->r_info);
603 ret->elf.dynindx = -1;
604 ret->elf.plt.offset = (bfd_vma) -1;
605 ret->elf.got.offset = (bfd_vma) -1;
606 *slot = ret;
608 return &ret->elf;
611 /* Create an X86-64 ELF linker hash table. */
613 static struct bfd_link_hash_table *
614 elf64_x86_64_link_hash_table_create (bfd *abfd)
616 struct elf64_x86_64_link_hash_table *ret;
617 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table);
619 ret = (struct elf64_x86_64_link_hash_table *) bfd_malloc (amt);
620 if (ret == NULL)
621 return NULL;
623 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd,
624 elf64_x86_64_link_hash_newfunc,
625 sizeof (struct elf64_x86_64_link_hash_entry)))
627 free (ret);
628 return NULL;
631 ret->sdynbss = NULL;
632 ret->srelbss = NULL;
633 ret->sym_cache.abfd = NULL;
634 ret->tlsdesc_plt = 0;
635 ret->tlsdesc_got = 0;
636 ret->tls_ld_got.refcount = 0;
637 ret->sgotplt_jump_table_size = 0;
638 ret->tls_module_base = NULL;
640 ret->loc_hash_table = htab_try_create (1024,
641 elf64_x86_64_local_htab_hash,
642 elf64_x86_64_local_htab_eq,
643 NULL);
644 ret->loc_hash_memory = objalloc_create ();
645 if (!ret->loc_hash_table || !ret->loc_hash_memory)
647 free (ret);
648 return NULL;
651 return &ret->elf.root;
654 /* Destroy an X86-64 ELF linker hash table. */
656 static void
657 elf64_x86_64_link_hash_table_free (struct bfd_link_hash_table *hash)
659 struct elf64_x86_64_link_hash_table *htab
660 = (struct elf64_x86_64_link_hash_table *) hash;
662 if (htab->loc_hash_table)
663 htab_delete (htab->loc_hash_table);
664 if (htab->loc_hash_memory)
665 objalloc_free ((struct objalloc *) htab->loc_hash_memory);
666 _bfd_generic_link_hash_table_free (hash);
669 /* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and
670 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our
671 hash table. */
673 static bfd_boolean
674 elf64_x86_64_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info)
676 struct elf64_x86_64_link_hash_table *htab;
678 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
679 return FALSE;
681 htab = elf64_x86_64_hash_table (info);
682 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
683 if (!info->shared)
684 htab->srelbss = bfd_get_section_by_name (dynobj, ".rela.bss");
686 if (!htab->sdynbss
687 || (!info->shared && !htab->srelbss))
688 abort ();
690 return TRUE;
693 /* Copy the extra info we tack onto an elf_link_hash_entry. */
695 static void
696 elf64_x86_64_copy_indirect_symbol (struct bfd_link_info *info,
697 struct elf_link_hash_entry *dir,
698 struct elf_link_hash_entry *ind)
700 struct elf64_x86_64_link_hash_entry *edir, *eind;
702 edir = (struct elf64_x86_64_link_hash_entry *) dir;
703 eind = (struct elf64_x86_64_link_hash_entry *) ind;
705 if (eind->dyn_relocs != NULL)
707 if (edir->dyn_relocs != NULL)
709 struct elf_dyn_relocs **pp;
710 struct elf_dyn_relocs *p;
712 /* Add reloc counts against the indirect sym to the direct sym
713 list. Merge any entries against the same section. */
714 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
716 struct elf_dyn_relocs *q;
718 for (q = edir->dyn_relocs; q != NULL; q = q->next)
719 if (q->sec == p->sec)
721 q->pc_count += p->pc_count;
722 q->count += p->count;
723 *pp = p->next;
724 break;
726 if (q == NULL)
727 pp = &p->next;
729 *pp = edir->dyn_relocs;
732 edir->dyn_relocs = eind->dyn_relocs;
733 eind->dyn_relocs = NULL;
736 if (ind->root.type == bfd_link_hash_indirect
737 && dir->got.refcount <= 0)
739 edir->tls_type = eind->tls_type;
740 eind->tls_type = GOT_UNKNOWN;
743 if (ELIMINATE_COPY_RELOCS
744 && ind->root.type != bfd_link_hash_indirect
745 && dir->dynamic_adjusted)
747 /* If called to transfer flags for a weakdef during processing
748 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
749 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
750 dir->ref_dynamic |= ind->ref_dynamic;
751 dir->ref_regular |= ind->ref_regular;
752 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
753 dir->needs_plt |= ind->needs_plt;
754 dir->pointer_equality_needed |= ind->pointer_equality_needed;
756 else
757 _bfd_elf_link_hash_copy_indirect (info, dir, ind);
760 static bfd_boolean
761 elf64_x86_64_elf_object_p (bfd *abfd)
763 /* Set the right machine number for an x86-64 elf64 file. */
764 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
765 return TRUE;
768 typedef union
770 unsigned char c[2];
771 uint16_t i;
773 x86_64_opcode16;
775 typedef union
777 unsigned char c[4];
778 uint32_t i;
780 x86_64_opcode32;
782 /* Return TRUE if the TLS access code sequence support transition
783 from R_TYPE. */
785 static bfd_boolean
786 elf64_x86_64_check_tls_transition (bfd *abfd, asection *sec,
787 bfd_byte *contents,
788 Elf_Internal_Shdr *symtab_hdr,
789 struct elf_link_hash_entry **sym_hashes,
790 unsigned int r_type,
791 const Elf_Internal_Rela *rel,
792 const Elf_Internal_Rela *relend)
794 unsigned int val;
795 unsigned long r_symndx;
796 struct elf_link_hash_entry *h;
797 bfd_vma offset;
799 /* Get the section contents. */
800 if (contents == NULL)
802 if (elf_section_data (sec)->this_hdr.contents != NULL)
803 contents = elf_section_data (sec)->this_hdr.contents;
804 else
806 /* FIXME: How to better handle error condition? */
807 if (!bfd_malloc_and_get_section (abfd, sec, &contents))
808 return FALSE;
810 /* Cache the section contents for elf_link_input_bfd. */
811 elf_section_data (sec)->this_hdr.contents = contents;
815 offset = rel->r_offset;
816 switch (r_type)
818 case R_X86_64_TLSGD:
819 case R_X86_64_TLSLD:
820 if ((rel + 1) >= relend)
821 return FALSE;
823 if (r_type == R_X86_64_TLSGD)
825 /* Check transition from GD access model. Only
826 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
827 .word 0x6666; rex64; call __tls_get_addr
828 can transit to different access model. */
830 static x86_64_opcode32 leaq = { { 0x66, 0x48, 0x8d, 0x3d } },
831 call = { { 0x66, 0x66, 0x48, 0xe8 } };
832 if (offset < 4
833 || (offset + 12) > sec->size
834 || bfd_get_32 (abfd, contents + offset - 4) != leaq.i
835 || bfd_get_32 (abfd, contents + offset + 4) != call.i)
836 return FALSE;
838 else
840 /* Check transition from LD access model. Only
841 leaq foo@tlsld(%rip), %rdi;
842 call __tls_get_addr
843 can transit to different access model. */
845 static x86_64_opcode32 ld = { { 0x48, 0x8d, 0x3d, 0xe8 } };
846 x86_64_opcode32 op;
848 if (offset < 3 || (offset + 9) > sec->size)
849 return FALSE;
851 op.i = bfd_get_32 (abfd, contents + offset - 3);
852 op.c[3] = bfd_get_8 (abfd, contents + offset + 4);
853 if (op.i != ld.i)
854 return FALSE;
857 r_symndx = ELF64_R_SYM (rel[1].r_info);
858 if (r_symndx < symtab_hdr->sh_info)
859 return FALSE;
861 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
862 /* Use strncmp to check __tls_get_addr since __tls_get_addr
863 may be versioned. */
864 return (h != NULL
865 && h->root.root.string != NULL
866 && (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PC32
867 || ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32)
868 && (strncmp (h->root.root.string,
869 "__tls_get_addr", 14) == 0));
871 case R_X86_64_GOTTPOFF:
872 /* Check transition from IE access model:
873 movq foo@gottpoff(%rip), %reg
874 addq foo@gottpoff(%rip), %reg
877 if (offset < 3 || (offset + 4) > sec->size)
878 return FALSE;
880 val = bfd_get_8 (abfd, contents + offset - 3);
881 if (val != 0x48 && val != 0x4c)
882 return FALSE;
884 val = bfd_get_8 (abfd, contents + offset - 2);
885 if (val != 0x8b && val != 0x03)
886 return FALSE;
888 val = bfd_get_8 (abfd, contents + offset - 1);
889 return (val & 0xc7) == 5;
891 case R_X86_64_GOTPC32_TLSDESC:
892 /* Check transition from GDesc access model:
893 leaq x@tlsdesc(%rip), %rax
895 Make sure it's a leaq adding rip to a 32-bit offset
896 into any register, although it's probably almost always
897 going to be rax. */
899 if (offset < 3 || (offset + 4) > sec->size)
900 return FALSE;
902 val = bfd_get_8 (abfd, contents + offset - 3);
903 if ((val & 0xfb) != 0x48)
904 return FALSE;
906 if (bfd_get_8 (abfd, contents + offset - 2) != 0x8d)
907 return FALSE;
909 val = bfd_get_8 (abfd, contents + offset - 1);
910 return (val & 0xc7) == 0x05;
912 case R_X86_64_TLSDESC_CALL:
913 /* Check transition from GDesc access model:
914 call *x@tlsdesc(%rax)
916 if (offset + 2 <= sec->size)
918 /* Make sure that it's a call *x@tlsdesc(%rax). */
919 static x86_64_opcode16 call = { { 0xff, 0x10 } };
920 return bfd_get_16 (abfd, contents + offset) == call.i;
923 return FALSE;
925 default:
926 abort ();
930 /* Return TRUE if the TLS access transition is OK or no transition
931 will be performed. Update R_TYPE if there is a transition. */
933 static bfd_boolean
934 elf64_x86_64_tls_transition (struct bfd_link_info *info, bfd *abfd,
935 asection *sec, bfd_byte *contents,
936 Elf_Internal_Shdr *symtab_hdr,
937 struct elf_link_hash_entry **sym_hashes,
938 unsigned int *r_type, int tls_type,
939 const Elf_Internal_Rela *rel,
940 const Elf_Internal_Rela *relend,
941 struct elf_link_hash_entry *h,
942 unsigned long r_symndx)
944 unsigned int from_type = *r_type;
945 unsigned int to_type = from_type;
946 bfd_boolean check = TRUE;
948 switch (from_type)
950 case R_X86_64_TLSGD:
951 case R_X86_64_GOTPC32_TLSDESC:
952 case R_X86_64_TLSDESC_CALL:
953 case R_X86_64_GOTTPOFF:
954 if (info->executable)
956 if (h == NULL)
957 to_type = R_X86_64_TPOFF32;
958 else
959 to_type = R_X86_64_GOTTPOFF;
962 /* When we are called from elf64_x86_64_relocate_section,
963 CONTENTS isn't NULL and there may be additional transitions
964 based on TLS_TYPE. */
965 if (contents != NULL)
967 unsigned int new_to_type = to_type;
969 if (info->executable
970 && h != NULL
971 && h->dynindx == -1
972 && tls_type == GOT_TLS_IE)
973 new_to_type = R_X86_64_TPOFF32;
975 if (to_type == R_X86_64_TLSGD
976 || to_type == R_X86_64_GOTPC32_TLSDESC
977 || to_type == R_X86_64_TLSDESC_CALL)
979 if (tls_type == GOT_TLS_IE)
980 new_to_type = R_X86_64_GOTTPOFF;
983 /* We checked the transition before when we were called from
984 elf64_x86_64_check_relocs. We only want to check the new
985 transition which hasn't been checked before. */
986 check = new_to_type != to_type && from_type == to_type;
987 to_type = new_to_type;
990 break;
992 case R_X86_64_TLSLD:
993 if (info->executable)
994 to_type = R_X86_64_TPOFF32;
995 break;
997 default:
998 return TRUE;
1001 /* Return TRUE if there is no transition. */
1002 if (from_type == to_type)
1003 return TRUE;
1005 /* Check if the transition can be performed. */
1006 if (check
1007 && ! elf64_x86_64_check_tls_transition (abfd, sec, contents,
1008 symtab_hdr, sym_hashes,
1009 from_type, rel, relend))
1011 reloc_howto_type *from, *to;
1012 const char *name;
1014 from = elf64_x86_64_rtype_to_howto (abfd, from_type);
1015 to = elf64_x86_64_rtype_to_howto (abfd, to_type);
1017 if (h)
1018 name = h->root.root.string;
1019 else
1021 Elf_Internal_Sym *isym;
1022 struct elf64_x86_64_link_hash_table *htab;
1023 htab = elf64_x86_64_hash_table (info);
1024 isym = bfd_sym_from_r_symndx (&htab->sym_cache,
1025 abfd, r_symndx);
1026 name = bfd_elf_sym_name (abfd, symtab_hdr, isym, NULL);
1029 (*_bfd_error_handler)
1030 (_("%B: TLS transition from %s to %s against `%s' at 0x%lx "
1031 "in section `%A' failed"),
1032 abfd, sec, from->name, to->name, name,
1033 (unsigned long) rel->r_offset);
1034 bfd_set_error (bfd_error_bad_value);
1035 return FALSE;
1038 *r_type = to_type;
1039 return TRUE;
1042 /* Look through the relocs for a section during the first phase, and
1043 calculate needed space in the global offset table, procedure
1044 linkage table, and dynamic reloc sections. */
1046 static bfd_boolean
1047 elf64_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
1048 asection *sec,
1049 const Elf_Internal_Rela *relocs)
1051 struct elf64_x86_64_link_hash_table *htab;
1052 Elf_Internal_Shdr *symtab_hdr;
1053 struct elf_link_hash_entry **sym_hashes;
1054 const Elf_Internal_Rela *rel;
1055 const Elf_Internal_Rela *rel_end;
1056 asection *sreloc;
1058 if (info->relocatable)
1059 return TRUE;
1061 BFD_ASSERT (is_x86_64_elf (abfd));
1063 htab = elf64_x86_64_hash_table (info);
1064 symtab_hdr = &elf_symtab_hdr (abfd);
1065 sym_hashes = elf_sym_hashes (abfd);
1067 sreloc = NULL;
1069 rel_end = relocs + sec->reloc_count;
1070 for (rel = relocs; rel < rel_end; rel++)
1072 unsigned int r_type;
1073 unsigned long r_symndx;
1074 struct elf_link_hash_entry *h;
1075 Elf_Internal_Sym *isym;
1076 const char *name;
1078 r_symndx = ELF64_R_SYM (rel->r_info);
1079 r_type = ELF64_R_TYPE (rel->r_info);
1081 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
1083 (*_bfd_error_handler) (_("%B: bad symbol index: %d"),
1084 abfd, r_symndx);
1085 return FALSE;
1088 if (r_symndx < symtab_hdr->sh_info)
1090 /* A local symbol. */
1091 isym = bfd_sym_from_r_symndx (&htab->sym_cache,
1092 abfd, r_symndx);
1093 if (isym == NULL)
1094 return FALSE;
1096 /* Check relocation against local STT_GNU_IFUNC symbol. */
1097 if (ELF64_ST_TYPE (isym->st_info) == STT_GNU_IFUNC)
1099 h = elf64_x86_64_get_local_sym_hash (htab, abfd, rel,
1100 TRUE);
1101 if (h == NULL)
1102 return FALSE;
1104 /* Fake a STT_GNU_IFUNC symbol. */
1105 h->type = STT_GNU_IFUNC;
1106 h->def_regular = 1;
1107 h->ref_regular = 1;
1108 h->forced_local = 1;
1109 h->root.type = bfd_link_hash_defined;
1111 else
1112 h = NULL;
1114 else
1116 isym = NULL;
1117 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1118 while (h->root.type == bfd_link_hash_indirect
1119 || h->root.type == bfd_link_hash_warning)
1120 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1123 if (h != NULL)
1125 /* Create the ifunc sections for static executables. If we
1126 never see an indirect function symbol nor we are building
1127 a static executable, those sections will be empty and
1128 won't appear in output. */
1129 switch (r_type)
1131 default:
1132 break;
1134 case R_X86_64_32S:
1135 case R_X86_64_32:
1136 case R_X86_64_64:
1137 case R_X86_64_PC32:
1138 case R_X86_64_PC64:
1139 case R_X86_64_PLT32:
1140 case R_X86_64_GOTPCREL:
1141 case R_X86_64_GOTPCREL64:
1142 if (!_bfd_elf_create_ifunc_sections (abfd, info))
1143 return FALSE;
1144 break;
1147 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle
1148 it here if it is defined in a non-shared object. */
1149 if (h->type == STT_GNU_IFUNC
1150 && h->def_regular)
1152 /* It is referenced by a non-shared object. */
1153 h->ref_regular = 1;
1154 h->needs_plt = 1;
1156 /* STT_GNU_IFUNC symbol must go through PLT. */
1157 h->plt.refcount += 1;
1159 /* STT_GNU_IFUNC needs dynamic sections. */
1160 if (htab->elf.dynobj == NULL)
1161 htab->elf.dynobj = abfd;
1163 switch (r_type)
1165 default:
1166 if (h->root.root.string)
1167 name = h->root.root.string;
1168 else
1169 name = bfd_elf_sym_name (abfd, symtab_hdr, isym,
1170 NULL);
1171 (*_bfd_error_handler)
1172 (_("%B: relocation %s against STT_GNU_IFUNC "
1173 "symbol `%s' isn't handled by %s"), abfd,
1174 x86_64_elf_howto_table[r_type].name,
1175 name, __FUNCTION__);
1176 bfd_set_error (bfd_error_bad_value);
1177 return FALSE;
1179 case R_X86_64_64:
1180 h->non_got_ref = 1;
1181 h->pointer_equality_needed = 1;
1182 if (info->shared)
1184 /* We must copy these reloc types into the output
1185 file. Create a reloc section in dynobj and
1186 make room for this reloc. */
1187 sreloc = _bfd_elf_create_ifunc_dyn_reloc
1188 (abfd, info, sec, sreloc,
1189 &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs);
1190 if (sreloc == NULL)
1191 return FALSE;
1193 break;
1195 case R_X86_64_32S:
1196 case R_X86_64_32:
1197 case R_X86_64_PC32:
1198 case R_X86_64_PC64:
1199 h->non_got_ref = 1;
1200 if (r_type != R_X86_64_PC32
1201 && r_type != R_X86_64_PC64)
1202 h->pointer_equality_needed = 1;
1203 break;
1205 case R_X86_64_PLT32:
1206 break;
1208 case R_X86_64_GOTPCREL:
1209 case R_X86_64_GOTPCREL64:
1210 h->got.refcount += 1;
1211 if (htab->elf.sgot == NULL
1212 && !_bfd_elf_create_got_section (htab->elf.dynobj,
1213 info))
1214 return FALSE;
1215 break;
1218 continue;
1222 if (! elf64_x86_64_tls_transition (info, abfd, sec, NULL,
1223 symtab_hdr, sym_hashes,
1224 &r_type, GOT_UNKNOWN,
1225 rel, rel_end, h, r_symndx))
1226 return FALSE;
1228 switch (r_type)
1230 case R_X86_64_TLSLD:
1231 htab->tls_ld_got.refcount += 1;
1232 goto create_got;
1234 case R_X86_64_TPOFF32:
1235 if (!info->executable)
1237 if (h)
1238 name = h->root.root.string;
1239 else
1240 name = bfd_elf_sym_name (abfd, symtab_hdr, isym,
1241 NULL);
1242 (*_bfd_error_handler)
1243 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
1244 abfd,
1245 x86_64_elf_howto_table[r_type].name, name);
1246 bfd_set_error (bfd_error_bad_value);
1247 return FALSE;
1249 break;
1251 case R_X86_64_GOTTPOFF:
1252 if (!info->executable)
1253 info->flags |= DF_STATIC_TLS;
1254 /* Fall through */
1256 case R_X86_64_GOT32:
1257 case R_X86_64_GOTPCREL:
1258 case R_X86_64_TLSGD:
1259 case R_X86_64_GOT64:
1260 case R_X86_64_GOTPCREL64:
1261 case R_X86_64_GOTPLT64:
1262 case R_X86_64_GOTPC32_TLSDESC:
1263 case R_X86_64_TLSDESC_CALL:
1264 /* This symbol requires a global offset table entry. */
1266 int tls_type, old_tls_type;
1268 switch (r_type)
1270 default: tls_type = GOT_NORMAL; break;
1271 case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
1272 case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
1273 case R_X86_64_GOTPC32_TLSDESC:
1274 case R_X86_64_TLSDESC_CALL:
1275 tls_type = GOT_TLS_GDESC; break;
1278 if (h != NULL)
1280 if (r_type == R_X86_64_GOTPLT64)
1282 /* This relocation indicates that we also need
1283 a PLT entry, as this is a function. We don't need
1284 a PLT entry for local symbols. */
1285 h->needs_plt = 1;
1286 h->plt.refcount += 1;
1288 h->got.refcount += 1;
1289 old_tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1291 else
1293 bfd_signed_vma *local_got_refcounts;
1295 /* This is a global offset table entry for a local symbol. */
1296 local_got_refcounts = elf_local_got_refcounts (abfd);
1297 if (local_got_refcounts == NULL)
1299 bfd_size_type size;
1301 size = symtab_hdr->sh_info;
1302 size *= sizeof (bfd_signed_vma)
1303 + sizeof (bfd_vma) + sizeof (char);
1304 local_got_refcounts = ((bfd_signed_vma *)
1305 bfd_zalloc (abfd, size));
1306 if (local_got_refcounts == NULL)
1307 return FALSE;
1308 elf_local_got_refcounts (abfd) = local_got_refcounts;
1309 elf64_x86_64_local_tlsdesc_gotent (abfd)
1310 = (bfd_vma *) (local_got_refcounts + symtab_hdr->sh_info);
1311 elf64_x86_64_local_got_tls_type (abfd)
1312 = (char *) (local_got_refcounts + 2 * symtab_hdr->sh_info);
1314 local_got_refcounts[r_symndx] += 1;
1315 old_tls_type
1316 = elf64_x86_64_local_got_tls_type (abfd) [r_symndx];
1319 /* If a TLS symbol is accessed using IE at least once,
1320 there is no point to use dynamic model for it. */
1321 if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
1322 && (! GOT_TLS_GD_ANY_P (old_tls_type)
1323 || tls_type != GOT_TLS_IE))
1325 if (old_tls_type == GOT_TLS_IE && GOT_TLS_GD_ANY_P (tls_type))
1326 tls_type = old_tls_type;
1327 else if (GOT_TLS_GD_ANY_P (old_tls_type)
1328 && GOT_TLS_GD_ANY_P (tls_type))
1329 tls_type |= old_tls_type;
1330 else
1332 if (h)
1333 name = h->root.root.string;
1334 else
1335 name = bfd_elf_sym_name (abfd, symtab_hdr,
1336 isym, NULL);
1337 (*_bfd_error_handler)
1338 (_("%B: '%s' accessed both as normal and thread local symbol"),
1339 abfd, name);
1340 return FALSE;
1344 if (old_tls_type != tls_type)
1346 if (h != NULL)
1347 elf64_x86_64_hash_entry (h)->tls_type = tls_type;
1348 else
1349 elf64_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
1352 /* Fall through */
1354 case R_X86_64_GOTOFF64:
1355 case R_X86_64_GOTPC32:
1356 case R_X86_64_GOTPC64:
1357 create_got:
1358 if (htab->elf.sgot == NULL)
1360 if (htab->elf.dynobj == NULL)
1361 htab->elf.dynobj = abfd;
1362 if (!_bfd_elf_create_got_section (htab->elf.dynobj,
1363 info))
1364 return FALSE;
1366 break;
1368 case R_X86_64_PLT32:
1369 /* This symbol requires a procedure linkage table entry. We
1370 actually build the entry in adjust_dynamic_symbol,
1371 because this might be a case of linking PIC code which is
1372 never referenced by a dynamic object, in which case we
1373 don't need to generate a procedure linkage table entry
1374 after all. */
1376 /* If this is a local symbol, we resolve it directly without
1377 creating a procedure linkage table entry. */
1378 if (h == NULL)
1379 continue;
1381 h->needs_plt = 1;
1382 h->plt.refcount += 1;
1383 break;
1385 case R_X86_64_PLTOFF64:
1386 /* This tries to form the 'address' of a function relative
1387 to GOT. For global symbols we need a PLT entry. */
1388 if (h != NULL)
1390 h->needs_plt = 1;
1391 h->plt.refcount += 1;
1393 goto create_got;
1395 case R_X86_64_8:
1396 case R_X86_64_16:
1397 case R_X86_64_32:
1398 case R_X86_64_32S:
1399 /* Let's help debug shared library creation. These relocs
1400 cannot be used in shared libs. Don't error out for
1401 sections we don't care about, such as debug sections or
1402 non-constant sections. */
1403 if (info->shared
1404 && (sec->flags & SEC_ALLOC) != 0
1405 && (sec->flags & SEC_READONLY) != 0)
1407 if (h)
1408 name = h->root.root.string;
1409 else
1410 name = bfd_elf_sym_name (abfd, symtab_hdr, isym, NULL);
1411 (*_bfd_error_handler)
1412 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
1413 abfd, x86_64_elf_howto_table[r_type].name, name);
1414 bfd_set_error (bfd_error_bad_value);
1415 return FALSE;
1417 /* Fall through. */
1419 case R_X86_64_PC8:
1420 case R_X86_64_PC16:
1421 case R_X86_64_PC32:
1422 case R_X86_64_PC64:
1423 case R_X86_64_64:
1424 if (h != NULL && info->executable)
1426 /* If this reloc is in a read-only section, we might
1427 need a copy reloc. We can't check reliably at this
1428 stage whether the section is read-only, as input
1429 sections have not yet been mapped to output sections.
1430 Tentatively set the flag for now, and correct in
1431 adjust_dynamic_symbol. */
1432 h->non_got_ref = 1;
1434 /* We may need a .plt entry if the function this reloc
1435 refers to is in a shared lib. */
1436 h->plt.refcount += 1;
1437 if (r_type != R_X86_64_PC32 && r_type != R_X86_64_PC64)
1438 h->pointer_equality_needed = 1;
1441 /* If we are creating a shared library, and this is a reloc
1442 against a global symbol, or a non PC relative reloc
1443 against a local symbol, then we need to copy the reloc
1444 into the shared library. However, if we are linking with
1445 -Bsymbolic, we do not need to copy a reloc against a
1446 global symbol which is defined in an object we are
1447 including in the link (i.e., DEF_REGULAR is set). At
1448 this point we have not seen all the input files, so it is
1449 possible that DEF_REGULAR is not set now but will be set
1450 later (it is never cleared). In case of a weak definition,
1451 DEF_REGULAR may be cleared later by a strong definition in
1452 a shared library. We account for that possibility below by
1453 storing information in the relocs_copied field of the hash
1454 table entry. A similar situation occurs when creating
1455 shared libraries and symbol visibility changes render the
1456 symbol local.
1458 If on the other hand, we are creating an executable, we
1459 may need to keep relocations for symbols satisfied by a
1460 dynamic library if we manage to avoid copy relocs for the
1461 symbol. */
1462 if ((info->shared
1463 && (sec->flags & SEC_ALLOC) != 0
1464 && (! IS_X86_64_PCREL_TYPE (r_type)
1465 || (h != NULL
1466 && (! SYMBOLIC_BIND (info, h)
1467 || h->root.type == bfd_link_hash_defweak
1468 || !h->def_regular))))
1469 || (ELIMINATE_COPY_RELOCS
1470 && !info->shared
1471 && (sec->flags & SEC_ALLOC) != 0
1472 && h != NULL
1473 && (h->root.type == bfd_link_hash_defweak
1474 || !h->def_regular)))
1476 struct elf_dyn_relocs *p;
1477 struct elf_dyn_relocs **head;
1479 /* We must copy these reloc types into the output file.
1480 Create a reloc section in dynobj and make room for
1481 this reloc. */
1482 if (sreloc == NULL)
1484 if (htab->elf.dynobj == NULL)
1485 htab->elf.dynobj = abfd;
1487 sreloc = _bfd_elf_make_dynamic_reloc_section
1488 (sec, htab->elf.dynobj, 3, abfd, /*rela?*/ TRUE);
1490 if (sreloc == NULL)
1491 return FALSE;
1494 /* If this is a global symbol, we count the number of
1495 relocations we need for this symbol. */
1496 if (h != NULL)
1498 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs;
1500 else
1502 /* Track dynamic relocs needed for local syms too.
1503 We really need local syms available to do this
1504 easily. Oh well. */
1505 asection *s;
1506 void **vpp;
1507 Elf_Internal_Sym *isym;
1509 isym = bfd_sym_from_r_symndx (&htab->sym_cache,
1510 abfd, r_symndx);
1511 if (isym == NULL)
1512 return FALSE;
1514 s = bfd_section_from_elf_index (abfd, isym->st_shndx);
1515 if (s == NULL)
1516 s = sec;
1518 /* Beware of type punned pointers vs strict aliasing
1519 rules. */
1520 vpp = &(elf_section_data (s)->local_dynrel);
1521 head = (struct elf_dyn_relocs **)vpp;
1524 p = *head;
1525 if (p == NULL || p->sec != sec)
1527 bfd_size_type amt = sizeof *p;
1529 p = ((struct elf_dyn_relocs *)
1530 bfd_alloc (htab->elf.dynobj, amt));
1531 if (p == NULL)
1532 return FALSE;
1533 p->next = *head;
1534 *head = p;
1535 p->sec = sec;
1536 p->count = 0;
1537 p->pc_count = 0;
1540 p->count += 1;
1541 if (IS_X86_64_PCREL_TYPE (r_type))
1542 p->pc_count += 1;
1544 break;
1546 /* This relocation describes the C++ object vtable hierarchy.
1547 Reconstruct it for later use during GC. */
1548 case R_X86_64_GNU_VTINHERIT:
1549 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
1550 return FALSE;
1551 break;
1553 /* This relocation describes which C++ vtable entries are actually
1554 used. Record for later use during GC. */
1555 case R_X86_64_GNU_VTENTRY:
1556 BFD_ASSERT (h != NULL);
1557 if (h != NULL
1558 && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
1559 return FALSE;
1560 break;
1562 default:
1563 break;
1567 return TRUE;
1570 /* Return the section that should be marked against GC for a given
1571 relocation. */
1573 static asection *
1574 elf64_x86_64_gc_mark_hook (asection *sec,
1575 struct bfd_link_info *info,
1576 Elf_Internal_Rela *rel,
1577 struct elf_link_hash_entry *h,
1578 Elf_Internal_Sym *sym)
1580 if (h != NULL)
1581 switch (ELF64_R_TYPE (rel->r_info))
1583 case R_X86_64_GNU_VTINHERIT:
1584 case R_X86_64_GNU_VTENTRY:
1585 return NULL;
1588 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
1591 /* Update the got entry reference counts for the section being removed. */
1593 static bfd_boolean
1594 elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
1595 asection *sec,
1596 const Elf_Internal_Rela *relocs)
1598 Elf_Internal_Shdr *symtab_hdr;
1599 struct elf_link_hash_entry **sym_hashes;
1600 bfd_signed_vma *local_got_refcounts;
1601 const Elf_Internal_Rela *rel, *relend;
1603 if (info->relocatable)
1604 return TRUE;
1606 elf_section_data (sec)->local_dynrel = NULL;
1608 symtab_hdr = &elf_symtab_hdr (abfd);
1609 sym_hashes = elf_sym_hashes (abfd);
1610 local_got_refcounts = elf_local_got_refcounts (abfd);
1612 relend = relocs + sec->reloc_count;
1613 for (rel = relocs; rel < relend; rel++)
1615 unsigned long r_symndx;
1616 unsigned int r_type;
1617 struct elf_link_hash_entry *h = NULL;
1619 r_symndx = ELF64_R_SYM (rel->r_info);
1620 if (r_symndx >= symtab_hdr->sh_info)
1622 struct elf64_x86_64_link_hash_entry *eh;
1623 struct elf_dyn_relocs **pp;
1624 struct elf_dyn_relocs *p;
1626 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1627 while (h->root.type == bfd_link_hash_indirect
1628 || h->root.type == bfd_link_hash_warning)
1629 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1630 eh = (struct elf64_x86_64_link_hash_entry *) h;
1632 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1633 if (p->sec == sec)
1635 /* Everything must go for SEC. */
1636 *pp = p->next;
1637 break;
1641 r_type = ELF64_R_TYPE (rel->r_info);
1642 if (! elf64_x86_64_tls_transition (info, abfd, sec, NULL,
1643 symtab_hdr, sym_hashes,
1644 &r_type, GOT_UNKNOWN,
1645 rel, relend, h, r_symndx))
1646 return FALSE;
1648 switch (r_type)
1650 case R_X86_64_TLSLD:
1651 if (elf64_x86_64_hash_table (info)->tls_ld_got.refcount > 0)
1652 elf64_x86_64_hash_table (info)->tls_ld_got.refcount -= 1;
1653 break;
1655 case R_X86_64_TLSGD:
1656 case R_X86_64_GOTPC32_TLSDESC:
1657 case R_X86_64_TLSDESC_CALL:
1658 case R_X86_64_GOTTPOFF:
1659 case R_X86_64_GOT32:
1660 case R_X86_64_GOTPCREL:
1661 case R_X86_64_GOT64:
1662 case R_X86_64_GOTPCREL64:
1663 case R_X86_64_GOTPLT64:
1664 if (h != NULL)
1666 if (r_type == R_X86_64_GOTPLT64 && h->plt.refcount > 0)
1667 h->plt.refcount -= 1;
1668 if (h->got.refcount > 0)
1669 h->got.refcount -= 1;
1671 else if (local_got_refcounts != NULL)
1673 if (local_got_refcounts[r_symndx] > 0)
1674 local_got_refcounts[r_symndx] -= 1;
1676 break;
1678 case R_X86_64_8:
1679 case R_X86_64_16:
1680 case R_X86_64_32:
1681 case R_X86_64_64:
1682 case R_X86_64_32S:
1683 case R_X86_64_PC8:
1684 case R_X86_64_PC16:
1685 case R_X86_64_PC32:
1686 case R_X86_64_PC64:
1687 if (info->shared)
1688 break;
1689 /* Fall thru */
1691 case R_X86_64_PLT32:
1692 case R_X86_64_PLTOFF64:
1693 if (h != NULL)
1695 if (h->plt.refcount > 0)
1696 h->plt.refcount -= 1;
1698 break;
1700 default:
1701 break;
1705 return TRUE;
1708 /* Adjust a symbol defined by a dynamic object and referenced by a
1709 regular object. The current definition is in some section of the
1710 dynamic object, but we're not including those sections. We have to
1711 change the definition to something the rest of the link can
1712 understand. */
1714 static bfd_boolean
1715 elf64_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
1716 struct elf_link_hash_entry *h)
1718 struct elf64_x86_64_link_hash_table *htab;
1719 asection *s;
1721 /* STT_GNU_IFUNC symbol must go through PLT. */
1722 if (h->type == STT_GNU_IFUNC)
1724 if (h->plt.refcount <= 0)
1726 h->plt.offset = (bfd_vma) -1;
1727 h->needs_plt = 0;
1729 return TRUE;
1732 /* If this is a function, put it in the procedure linkage table. We
1733 will fill in the contents of the procedure linkage table later,
1734 when we know the address of the .got section. */
1735 if (h->type == STT_FUNC
1736 || h->needs_plt)
1738 if (h->plt.refcount <= 0
1739 || SYMBOL_CALLS_LOCAL (info, h)
1740 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1741 && h->root.type == bfd_link_hash_undefweak))
1743 /* This case can occur if we saw a PLT32 reloc in an input
1744 file, but the symbol was never referred to by a dynamic
1745 object, or if all references were garbage collected. In
1746 such a case, we don't actually need to build a procedure
1747 linkage table, and we can just do a PC32 reloc instead. */
1748 h->plt.offset = (bfd_vma) -1;
1749 h->needs_plt = 0;
1752 return TRUE;
1754 else
1755 /* It's possible that we incorrectly decided a .plt reloc was
1756 needed for an R_X86_64_PC32 reloc to a non-function sym in
1757 check_relocs. We can't decide accurately between function and
1758 non-function syms in check-relocs; Objects loaded later in
1759 the link may change h->type. So fix it now. */
1760 h->plt.offset = (bfd_vma) -1;
1762 /* If this is a weak symbol, and there is a real definition, the
1763 processor independent code will have arranged for us to see the
1764 real definition first, and we can just use the same value. */
1765 if (h->u.weakdef != NULL)
1767 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1768 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1769 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1770 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1771 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1772 h->non_got_ref = h->u.weakdef->non_got_ref;
1773 return TRUE;
1776 /* This is a reference to a symbol defined by a dynamic object which
1777 is not a function. */
1779 /* If we are creating a shared library, we must presume that the
1780 only references to the symbol are via the global offset table.
1781 For such cases we need not do anything here; the relocations will
1782 be handled correctly by relocate_section. */
1783 if (info->shared)
1784 return TRUE;
1786 /* If there are no references to this symbol that do not use the
1787 GOT, we don't need to generate a copy reloc. */
1788 if (!h->non_got_ref)
1789 return TRUE;
1791 /* If -z nocopyreloc was given, we won't generate them either. */
1792 if (info->nocopyreloc)
1794 h->non_got_ref = 0;
1795 return TRUE;
1798 if (ELIMINATE_COPY_RELOCS)
1800 struct elf64_x86_64_link_hash_entry * eh;
1801 struct elf_dyn_relocs *p;
1803 eh = (struct elf64_x86_64_link_hash_entry *) h;
1804 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1806 s = p->sec->output_section;
1807 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1808 break;
1811 /* If we didn't find any dynamic relocs in read-only sections, then
1812 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1813 if (p == NULL)
1815 h->non_got_ref = 0;
1816 return TRUE;
1820 if (h->size == 0)
1822 (*_bfd_error_handler) (_("dynamic variable `%s' is zero size"),
1823 h->root.root.string);
1824 return TRUE;
1827 /* We must allocate the symbol in our .dynbss section, which will
1828 become part of the .bss section of the executable. There will be
1829 an entry for this symbol in the .dynsym section. The dynamic
1830 object will contain position independent code, so all references
1831 from the dynamic object to this symbol will go through the global
1832 offset table. The dynamic linker will use the .dynsym entry to
1833 determine the address it must put in the global offset table, so
1834 both the dynamic object and the regular object will refer to the
1835 same memory location for the variable. */
1837 htab = elf64_x86_64_hash_table (info);
1839 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
1840 to copy the initial value out of the dynamic object and into the
1841 runtime process image. */
1842 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1844 htab->srelbss->size += sizeof (Elf64_External_Rela);
1845 h->needs_copy = 1;
1848 s = htab->sdynbss;
1850 return _bfd_elf_adjust_dynamic_copy (h, s);
1853 /* Allocate space in .plt, .got and associated reloc sections for
1854 dynamic relocs. */
1856 static bfd_boolean
1857 elf64_x86_64_allocate_dynrelocs (struct elf_link_hash_entry *h, void * inf)
1859 struct bfd_link_info *info;
1860 struct elf64_x86_64_link_hash_table *htab;
1861 struct elf64_x86_64_link_hash_entry *eh;
1862 struct elf_dyn_relocs *p;
1864 if (h->root.type == bfd_link_hash_indirect)
1865 return TRUE;
1867 if (h->root.type == bfd_link_hash_warning)
1868 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1869 eh = (struct elf64_x86_64_link_hash_entry *) h;
1871 info = (struct bfd_link_info *) inf;
1872 htab = elf64_x86_64_hash_table (info);
1874 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle it
1875 here if it is defined and referenced in a non-shared object. */
1876 if (h->type == STT_GNU_IFUNC
1877 && h->def_regular)
1878 return _bfd_elf_allocate_ifunc_dyn_relocs (info, h,
1879 &eh->dyn_relocs,
1880 PLT_ENTRY_SIZE,
1881 GOT_ENTRY_SIZE);
1882 else if (htab->elf.dynamic_sections_created
1883 && h->plt.refcount > 0)
1885 /* Make sure this symbol is output as a dynamic symbol.
1886 Undefined weak syms won't yet be marked as dynamic. */
1887 if (h->dynindx == -1
1888 && !h->forced_local)
1890 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1891 return FALSE;
1894 if (info->shared
1895 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
1897 asection *s = htab->elf.splt;
1899 /* If this is the first .plt entry, make room for the special
1900 first entry. */
1901 if (s->size == 0)
1902 s->size += PLT_ENTRY_SIZE;
1904 h->plt.offset = s->size;
1906 /* If this symbol is not defined in a regular file, and we are
1907 not generating a shared library, then set the symbol to this
1908 location in the .plt. This is required to make function
1909 pointers compare as equal between the normal executable and
1910 the shared library. */
1911 if (! info->shared
1912 && !h->def_regular)
1914 h->root.u.def.section = s;
1915 h->root.u.def.value = h->plt.offset;
1918 /* Make room for this entry. */
1919 s->size += PLT_ENTRY_SIZE;
1921 /* We also need to make an entry in the .got.plt section, which
1922 will be placed in the .got section by the linker script. */
1923 htab->elf.sgotplt->size += GOT_ENTRY_SIZE;
1925 /* We also need to make an entry in the .rela.plt section. */
1926 htab->elf.srelplt->size += sizeof (Elf64_External_Rela);
1927 htab->elf.srelplt->reloc_count++;
1929 else
1931 h->plt.offset = (bfd_vma) -1;
1932 h->needs_plt = 0;
1935 else
1937 h->plt.offset = (bfd_vma) -1;
1938 h->needs_plt = 0;
1941 eh->tlsdesc_got = (bfd_vma) -1;
1943 /* If R_X86_64_GOTTPOFF symbol is now local to the binary,
1944 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
1945 if (h->got.refcount > 0
1946 && info->executable
1947 && h->dynindx == -1
1948 && elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
1950 h->got.offset = (bfd_vma) -1;
1952 else if (h->got.refcount > 0)
1954 asection *s;
1955 bfd_boolean dyn;
1956 int tls_type = elf64_x86_64_hash_entry (h)->tls_type;
1958 /* Make sure this symbol is output as a dynamic symbol.
1959 Undefined weak syms won't yet be marked as dynamic. */
1960 if (h->dynindx == -1
1961 && !h->forced_local)
1963 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1964 return FALSE;
1967 if (GOT_TLS_GDESC_P (tls_type))
1969 eh->tlsdesc_got = htab->elf.sgotplt->size
1970 - elf64_x86_64_compute_jump_table_size (htab);
1971 htab->elf.sgotplt->size += 2 * GOT_ENTRY_SIZE;
1972 h->got.offset = (bfd_vma) -2;
1974 if (! GOT_TLS_GDESC_P (tls_type)
1975 || GOT_TLS_GD_P (tls_type))
1977 s = htab->elf.sgot;
1978 h->got.offset = s->size;
1979 s->size += GOT_ENTRY_SIZE;
1980 if (GOT_TLS_GD_P (tls_type))
1981 s->size += GOT_ENTRY_SIZE;
1983 dyn = htab->elf.dynamic_sections_created;
1984 /* R_X86_64_TLSGD needs one dynamic relocation if local symbol
1985 and two if global.
1986 R_X86_64_GOTTPOFF needs one dynamic relocation. */
1987 if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1)
1988 || tls_type == GOT_TLS_IE)
1989 htab->elf.srelgot->size += sizeof (Elf64_External_Rela);
1990 else if (GOT_TLS_GD_P (tls_type))
1991 htab->elf.srelgot->size += 2 * sizeof (Elf64_External_Rela);
1992 else if (! GOT_TLS_GDESC_P (tls_type)
1993 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1994 || h->root.type != bfd_link_hash_undefweak)
1995 && (info->shared
1996 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
1997 htab->elf.srelgot->size += sizeof (Elf64_External_Rela);
1998 if (GOT_TLS_GDESC_P (tls_type))
2000 htab->elf.srelplt->size += sizeof (Elf64_External_Rela);
2001 htab->tlsdesc_plt = (bfd_vma) -1;
2004 else
2005 h->got.offset = (bfd_vma) -1;
2007 if (eh->dyn_relocs == NULL)
2008 return TRUE;
2010 /* In the shared -Bsymbolic case, discard space allocated for
2011 dynamic pc-relative relocs against symbols which turn out to be
2012 defined in regular objects. For the normal shared case, discard
2013 space for pc-relative relocs that have become local due to symbol
2014 visibility changes. */
2016 if (info->shared)
2018 /* Relocs that use pc_count are those that appear on a call
2019 insn, or certain REL relocs that can generated via assembly.
2020 We want calls to protected symbols to resolve directly to the
2021 function rather than going via the plt. If people want
2022 function pointer comparisons to work as expected then they
2023 should avoid writing weird assembly. */
2024 if (SYMBOL_CALLS_LOCAL (info, h))
2026 struct elf_dyn_relocs **pp;
2028 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
2030 p->count -= p->pc_count;
2031 p->pc_count = 0;
2032 if (p->count == 0)
2033 *pp = p->next;
2034 else
2035 pp = &p->next;
2039 /* Also discard relocs on undefined weak syms with non-default
2040 visibility. */
2041 if (eh->dyn_relocs != NULL
2042 && h->root.type == bfd_link_hash_undefweak)
2044 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2045 eh->dyn_relocs = NULL;
2047 /* Make sure undefined weak symbols are output as a dynamic
2048 symbol in PIEs. */
2049 else if (h->dynindx == -1
2050 && ! h->forced_local
2051 && ! bfd_elf_link_record_dynamic_symbol (info, h))
2052 return FALSE;
2056 else if (ELIMINATE_COPY_RELOCS)
2058 /* For the non-shared case, discard space for relocs against
2059 symbols which turn out to need copy relocs or are not
2060 dynamic. */
2062 if (!h->non_got_ref
2063 && ((h->def_dynamic
2064 && !h->def_regular)
2065 || (htab->elf.dynamic_sections_created
2066 && (h->root.type == bfd_link_hash_undefweak
2067 || h->root.type == bfd_link_hash_undefined))))
2069 /* Make sure this symbol is output as a dynamic symbol.
2070 Undefined weak syms won't yet be marked as dynamic. */
2071 if (h->dynindx == -1
2072 && ! h->forced_local
2073 && ! bfd_elf_link_record_dynamic_symbol (info, h))
2074 return FALSE;
2076 /* If that succeeded, we know we'll be keeping all the
2077 relocs. */
2078 if (h->dynindx != -1)
2079 goto keep;
2082 eh->dyn_relocs = NULL;
2084 keep: ;
2087 /* Finally, allocate space. */
2088 for (p = eh->dyn_relocs; p != NULL; p = p->next)
2090 asection * sreloc;
2092 sreloc = elf_section_data (p->sec)->sreloc;
2094 BFD_ASSERT (sreloc != NULL);
2096 sreloc->size += p->count * sizeof (Elf64_External_Rela);
2099 return TRUE;
2102 /* Allocate space in .plt, .got and associated reloc sections for
2103 local dynamic relocs. */
2105 static bfd_boolean
2106 elf64_x86_64_allocate_local_dynrelocs (void **slot, void *inf)
2108 struct elf_link_hash_entry *h
2109 = (struct elf_link_hash_entry *) *slot;
2111 if (h->type != STT_GNU_IFUNC
2112 || !h->def_regular
2113 || !h->ref_regular
2114 || !h->forced_local
2115 || h->root.type != bfd_link_hash_defined)
2116 abort ();
2118 return elf64_x86_64_allocate_dynrelocs (h, inf);
2121 /* Find any dynamic relocs that apply to read-only sections. */
2123 static bfd_boolean
2124 elf64_x86_64_readonly_dynrelocs (struct elf_link_hash_entry *h, void * inf)
2126 struct elf64_x86_64_link_hash_entry *eh;
2127 struct elf_dyn_relocs *p;
2129 if (h->root.type == bfd_link_hash_warning)
2130 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2132 eh = (struct elf64_x86_64_link_hash_entry *) h;
2133 for (p = eh->dyn_relocs; p != NULL; p = p->next)
2135 asection *s = p->sec->output_section;
2137 if (s != NULL && (s->flags & SEC_READONLY) != 0)
2139 struct bfd_link_info *info = (struct bfd_link_info *) inf;
2141 info->flags |= DF_TEXTREL;
2143 /* Not an error, just cut short the traversal. */
2144 return FALSE;
2147 return TRUE;
2150 /* Set the sizes of the dynamic sections. */
2152 static bfd_boolean
2153 elf64_x86_64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
2154 struct bfd_link_info *info)
2156 struct elf64_x86_64_link_hash_table *htab;
2157 bfd *dynobj;
2158 asection *s;
2159 bfd_boolean relocs;
2160 bfd *ibfd;
2162 htab = elf64_x86_64_hash_table (info);
2163 dynobj = htab->elf.dynobj;
2164 if (dynobj == NULL)
2165 abort ();
2167 if (htab->elf.dynamic_sections_created)
2169 /* Set the contents of the .interp section to the interpreter. */
2170 if (info->executable)
2172 s = bfd_get_section_by_name (dynobj, ".interp");
2173 if (s == NULL)
2174 abort ();
2175 s->size = sizeof ELF_DYNAMIC_INTERPRETER;
2176 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
2180 /* Set up .got offsets for local syms, and space for local dynamic
2181 relocs. */
2182 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
2184 bfd_signed_vma *local_got;
2185 bfd_signed_vma *end_local_got;
2186 char *local_tls_type;
2187 bfd_vma *local_tlsdesc_gotent;
2188 bfd_size_type locsymcount;
2189 Elf_Internal_Shdr *symtab_hdr;
2190 asection *srel;
2192 if (! is_x86_64_elf (ibfd))
2193 continue;
2195 for (s = ibfd->sections; s != NULL; s = s->next)
2197 struct elf_dyn_relocs *p;
2199 for (p = (struct elf_dyn_relocs *)
2200 (elf_section_data (s)->local_dynrel);
2201 p != NULL;
2202 p = p->next)
2204 if (!bfd_is_abs_section (p->sec)
2205 && bfd_is_abs_section (p->sec->output_section))
2207 /* Input section has been discarded, either because
2208 it is a copy of a linkonce section or due to
2209 linker script /DISCARD/, so we'll be discarding
2210 the relocs too. */
2212 else if (p->count != 0)
2214 srel = elf_section_data (p->sec)->sreloc;
2215 srel->size += p->count * sizeof (Elf64_External_Rela);
2216 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
2217 info->flags |= DF_TEXTREL;
2222 local_got = elf_local_got_refcounts (ibfd);
2223 if (!local_got)
2224 continue;
2226 symtab_hdr = &elf_symtab_hdr (ibfd);
2227 locsymcount = symtab_hdr->sh_info;
2228 end_local_got = local_got + locsymcount;
2229 local_tls_type = elf64_x86_64_local_got_tls_type (ibfd);
2230 local_tlsdesc_gotent = elf64_x86_64_local_tlsdesc_gotent (ibfd);
2231 s = htab->elf.sgot;
2232 srel = htab->elf.srelgot;
2233 for (; local_got < end_local_got;
2234 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent)
2236 *local_tlsdesc_gotent = (bfd_vma) -1;
2237 if (*local_got > 0)
2239 if (GOT_TLS_GDESC_P (*local_tls_type))
2241 *local_tlsdesc_gotent = htab->elf.sgotplt->size
2242 - elf64_x86_64_compute_jump_table_size (htab);
2243 htab->elf.sgotplt->size += 2 * GOT_ENTRY_SIZE;
2244 *local_got = (bfd_vma) -2;
2246 if (! GOT_TLS_GDESC_P (*local_tls_type)
2247 || GOT_TLS_GD_P (*local_tls_type))
2249 *local_got = s->size;
2250 s->size += GOT_ENTRY_SIZE;
2251 if (GOT_TLS_GD_P (*local_tls_type))
2252 s->size += GOT_ENTRY_SIZE;
2254 if (info->shared
2255 || GOT_TLS_GD_ANY_P (*local_tls_type)
2256 || *local_tls_type == GOT_TLS_IE)
2258 if (GOT_TLS_GDESC_P (*local_tls_type))
2260 htab->elf.srelplt->size
2261 += sizeof (Elf64_External_Rela);
2262 htab->tlsdesc_plt = (bfd_vma) -1;
2264 if (! GOT_TLS_GDESC_P (*local_tls_type)
2265 || GOT_TLS_GD_P (*local_tls_type))
2266 srel->size += sizeof (Elf64_External_Rela);
2269 else
2270 *local_got = (bfd_vma) -1;
2274 if (htab->tls_ld_got.refcount > 0)
2276 /* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD
2277 relocs. */
2278 htab->tls_ld_got.offset = htab->elf.sgot->size;
2279 htab->elf.sgot->size += 2 * GOT_ENTRY_SIZE;
2280 htab->elf.srelgot->size += sizeof (Elf64_External_Rela);
2282 else
2283 htab->tls_ld_got.offset = -1;
2285 /* Allocate global sym .plt and .got entries, and space for global
2286 sym dynamic relocs. */
2287 elf_link_hash_traverse (&htab->elf, elf64_x86_64_allocate_dynrelocs,
2288 info);
2290 /* Allocate .plt and .got entries, and space for local symbols. */
2291 htab_traverse (htab->loc_hash_table,
2292 elf64_x86_64_allocate_local_dynrelocs,
2293 info);
2295 /* For every jump slot reserved in the sgotplt, reloc_count is
2296 incremented. However, when we reserve space for TLS descriptors,
2297 it's not incremented, so in order to compute the space reserved
2298 for them, it suffices to multiply the reloc count by the jump
2299 slot size. */
2300 if (htab->elf.srelplt)
2301 htab->sgotplt_jump_table_size
2302 = elf64_x86_64_compute_jump_table_size (htab);
2304 if (htab->tlsdesc_plt)
2306 /* If we're not using lazy TLS relocations, don't generate the
2307 PLT and GOT entries they require. */
2308 if ((info->flags & DF_BIND_NOW))
2309 htab->tlsdesc_plt = 0;
2310 else
2312 htab->tlsdesc_got = htab->elf.sgot->size;
2313 htab->elf.sgot->size += GOT_ENTRY_SIZE;
2314 /* Reserve room for the initial entry.
2315 FIXME: we could probably do away with it in this case. */
2316 if (htab->elf.splt->size == 0)
2317 htab->elf.splt->size += PLT_ENTRY_SIZE;
2318 htab->tlsdesc_plt = htab->elf.splt->size;
2319 htab->elf.splt->size += PLT_ENTRY_SIZE;
2323 /* We now have determined the sizes of the various dynamic sections.
2324 Allocate memory for them. */
2325 relocs = FALSE;
2326 for (s = dynobj->sections; s != NULL; s = s->next)
2328 if ((s->flags & SEC_LINKER_CREATED) == 0)
2329 continue;
2331 if (s == htab->elf.splt
2332 || s == htab->elf.sgot
2333 || s == htab->elf.sgotplt
2334 || s == htab->elf.iplt
2335 || s == htab->elf.igotplt
2336 || s == htab->sdynbss)
2338 /* Strip this section if we don't need it; see the
2339 comment below. */
2341 else if (CONST_STRNEQ (bfd_get_section_name (dynobj, s), ".rela"))
2343 if (s->size != 0 && s != htab->elf.srelplt)
2344 relocs = TRUE;
2346 /* We use the reloc_count field as a counter if we need
2347 to copy relocs into the output file. */
2348 if (s != htab->elf.srelplt)
2349 s->reloc_count = 0;
2351 else
2353 /* It's not one of our sections, so don't allocate space. */
2354 continue;
2357 if (s->size == 0)
2359 /* If we don't need this section, strip it from the
2360 output file. This is mostly to handle .rela.bss and
2361 .rela.plt. We must create both sections in
2362 create_dynamic_sections, because they must be created
2363 before the linker maps input sections to output
2364 sections. The linker does that before
2365 adjust_dynamic_symbol is called, and it is that
2366 function which decides whether anything needs to go
2367 into these sections. */
2369 s->flags |= SEC_EXCLUDE;
2370 continue;
2373 if ((s->flags & SEC_HAS_CONTENTS) == 0)
2374 continue;
2376 /* Allocate memory for the section contents. We use bfd_zalloc
2377 here in case unused entries are not reclaimed before the
2378 section's contents are written out. This should not happen,
2379 but this way if it does, we get a R_X86_64_NONE reloc instead
2380 of garbage. */
2381 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->size);
2382 if (s->contents == NULL)
2383 return FALSE;
2386 if (htab->elf.dynamic_sections_created)
2388 /* Add some entries to the .dynamic section. We fill in the
2389 values later, in elf64_x86_64_finish_dynamic_sections, but we
2390 must add the entries now so that we get the correct size for
2391 the .dynamic section. The DT_DEBUG entry is filled in by the
2392 dynamic linker and used by the debugger. */
2393 #define add_dynamic_entry(TAG, VAL) \
2394 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
2396 if (info->executable)
2398 if (!add_dynamic_entry (DT_DEBUG, 0))
2399 return FALSE;
2402 if (htab->elf.splt->size != 0)
2404 if (!add_dynamic_entry (DT_PLTGOT, 0)
2405 || !add_dynamic_entry (DT_PLTRELSZ, 0)
2406 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
2407 || !add_dynamic_entry (DT_JMPREL, 0))
2408 return FALSE;
2410 if (htab->tlsdesc_plt
2411 && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
2412 || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
2413 return FALSE;
2416 if (relocs)
2418 if (!add_dynamic_entry (DT_RELA, 0)
2419 || !add_dynamic_entry (DT_RELASZ, 0)
2420 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
2421 return FALSE;
2423 /* If any dynamic relocs apply to a read-only section,
2424 then we need a DT_TEXTREL entry. */
2425 if ((info->flags & DF_TEXTREL) == 0)
2426 elf_link_hash_traverse (&htab->elf,
2427 elf64_x86_64_readonly_dynrelocs,
2428 info);
2430 if ((info->flags & DF_TEXTREL) != 0)
2432 if (!add_dynamic_entry (DT_TEXTREL, 0))
2433 return FALSE;
2437 #undef add_dynamic_entry
2439 return TRUE;
2442 static bfd_boolean
2443 elf64_x86_64_always_size_sections (bfd *output_bfd,
2444 struct bfd_link_info *info)
2446 asection *tls_sec = elf_hash_table (info)->tls_sec;
2448 if (tls_sec)
2450 struct elf_link_hash_entry *tlsbase;
2452 tlsbase = elf_link_hash_lookup (elf_hash_table (info),
2453 "_TLS_MODULE_BASE_",
2454 FALSE, FALSE, FALSE);
2456 if (tlsbase && tlsbase->type == STT_TLS)
2458 struct bfd_link_hash_entry *bh = NULL;
2459 const struct elf_backend_data *bed
2460 = get_elf_backend_data (output_bfd);
2462 if (!(_bfd_generic_link_add_one_symbol
2463 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL,
2464 tls_sec, 0, NULL, FALSE,
2465 bed->collect, &bh)))
2466 return FALSE;
2468 elf64_x86_64_hash_table (info)->tls_module_base = bh;
2470 tlsbase = (struct elf_link_hash_entry *)bh;
2471 tlsbase->def_regular = 1;
2472 tlsbase->other = STV_HIDDEN;
2473 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE);
2477 return TRUE;
2480 /* _TLS_MODULE_BASE_ needs to be treated especially when linking
2481 executables. Rather than setting it to the beginning of the TLS
2482 section, we have to set it to the end. This function may be called
2483 multiple times, it is idempotent. */
2485 static void
2486 elf64_x86_64_set_tls_module_base (struct bfd_link_info *info)
2488 struct bfd_link_hash_entry *base;
2490 if (!info->executable)
2491 return;
2493 base = elf64_x86_64_hash_table (info)->tls_module_base;
2495 if (!base)
2496 return;
2498 base->u.def.value = elf_hash_table (info)->tls_size;
2501 /* Return the base VMA address which should be subtracted from real addresses
2502 when resolving @dtpoff relocation.
2503 This is PT_TLS segment p_vaddr. */
2505 static bfd_vma
2506 elf64_x86_64_dtpoff_base (struct bfd_link_info *info)
2508 /* If tls_sec is NULL, we should have signalled an error already. */
2509 if (elf_hash_table (info)->tls_sec == NULL)
2510 return 0;
2511 return elf_hash_table (info)->tls_sec->vma;
2514 /* Return the relocation value for @tpoff relocation
2515 if STT_TLS virtual address is ADDRESS. */
2517 static bfd_vma
2518 elf64_x86_64_tpoff (struct bfd_link_info *info, bfd_vma address)
2520 struct elf_link_hash_table *htab = elf_hash_table (info);
2522 /* If tls_segment is NULL, we should have signalled an error already. */
2523 if (htab->tls_sec == NULL)
2524 return 0;
2525 return address - htab->tls_size - htab->tls_sec->vma;
2528 /* Is the instruction before OFFSET in CONTENTS a 32bit relative
2529 branch? */
2531 static bfd_boolean
2532 is_32bit_relative_branch (bfd_byte *contents, bfd_vma offset)
2534 /* Opcode Instruction
2535 0xe8 call
2536 0xe9 jump
2537 0x0f 0x8x conditional jump */
2538 return ((offset > 0
2539 && (contents [offset - 1] == 0xe8
2540 || contents [offset - 1] == 0xe9))
2541 || (offset > 1
2542 && contents [offset - 2] == 0x0f
2543 && (contents [offset - 1] & 0xf0) == 0x80));
2546 /* Relocate an x86_64 ELF section. */
2548 static bfd_boolean
2549 elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
2550 bfd *input_bfd, asection *input_section,
2551 bfd_byte *contents, Elf_Internal_Rela *relocs,
2552 Elf_Internal_Sym *local_syms,
2553 asection **local_sections)
2555 struct elf64_x86_64_link_hash_table *htab;
2556 Elf_Internal_Shdr *symtab_hdr;
2557 struct elf_link_hash_entry **sym_hashes;
2558 bfd_vma *local_got_offsets;
2559 bfd_vma *local_tlsdesc_gotents;
2560 Elf_Internal_Rela *rel;
2561 Elf_Internal_Rela *relend;
2563 BFD_ASSERT (is_x86_64_elf (input_bfd));
2565 htab = elf64_x86_64_hash_table (info);
2566 symtab_hdr = &elf_symtab_hdr (input_bfd);
2567 sym_hashes = elf_sym_hashes (input_bfd);
2568 local_got_offsets = elf_local_got_offsets (input_bfd);
2569 local_tlsdesc_gotents = elf64_x86_64_local_tlsdesc_gotent (input_bfd);
2571 elf64_x86_64_set_tls_module_base (info);
2573 rel = relocs;
2574 relend = relocs + input_section->reloc_count;
2575 for (; rel < relend; rel++)
2577 unsigned int r_type;
2578 reloc_howto_type *howto;
2579 unsigned long r_symndx;
2580 struct elf_link_hash_entry *h;
2581 Elf_Internal_Sym *sym;
2582 asection *sec;
2583 bfd_vma off, offplt;
2584 bfd_vma relocation;
2585 bfd_boolean unresolved_reloc;
2586 bfd_reloc_status_type r;
2587 int tls_type;
2588 asection *base_got;
2590 r_type = ELF64_R_TYPE (rel->r_info);
2591 if (r_type == (int) R_X86_64_GNU_VTINHERIT
2592 || r_type == (int) R_X86_64_GNU_VTENTRY)
2593 continue;
2595 if (r_type >= R_X86_64_max)
2597 bfd_set_error (bfd_error_bad_value);
2598 return FALSE;
2601 howto = x86_64_elf_howto_table + r_type;
2602 r_symndx = ELF64_R_SYM (rel->r_info);
2603 h = NULL;
2604 sym = NULL;
2605 sec = NULL;
2606 unresolved_reloc = FALSE;
2607 if (r_symndx < symtab_hdr->sh_info)
2609 sym = local_syms + r_symndx;
2610 sec = local_sections[r_symndx];
2612 relocation = _bfd_elf_rela_local_sym (output_bfd, sym,
2613 &sec, rel);
2615 /* Relocate against local STT_GNU_IFUNC symbol. */
2616 if (!info->relocatable
2617 && ELF64_ST_TYPE (sym->st_info) == STT_GNU_IFUNC)
2619 h = elf64_x86_64_get_local_sym_hash (htab, input_bfd,
2620 rel, FALSE);
2621 if (h == NULL)
2622 abort ();
2624 /* Set STT_GNU_IFUNC symbol value. */
2625 h->root.u.def.value = sym->st_value;
2626 h->root.u.def.section = sec;
2629 else
2631 bfd_boolean warned;
2633 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
2634 r_symndx, symtab_hdr, sym_hashes,
2635 h, sec, relocation,
2636 unresolved_reloc, warned);
2639 if (sec != NULL && elf_discarded_section (sec))
2641 /* For relocs against symbols from removed linkonce sections,
2642 or sections discarded by a linker script, we just want the
2643 section contents zeroed. Avoid any special processing. */
2644 _bfd_clear_contents (howto, input_bfd, contents + rel->r_offset);
2645 rel->r_info = 0;
2646 rel->r_addend = 0;
2647 continue;
2650 if (info->relocatable)
2651 continue;
2653 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle
2654 it here if it is defined in a non-shared object. */
2655 if (h != NULL
2656 && h->type == STT_GNU_IFUNC
2657 && h->def_regular)
2659 asection *plt;
2660 bfd_vma plt_index;
2661 const char *name;
2663 if ((input_section->flags & SEC_ALLOC) == 0
2664 || h->plt.offset == (bfd_vma) -1)
2665 abort ();
2667 /* STT_GNU_IFUNC symbol must go through PLT. */
2668 plt = htab->elf.splt ? htab->elf.splt : htab->elf.iplt;
2669 relocation = (plt->output_section->vma
2670 + plt->output_offset + h->plt.offset);
2672 switch (r_type)
2674 default:
2675 if (h->root.root.string)
2676 name = h->root.root.string;
2677 else
2678 name = bfd_elf_sym_name (input_bfd, symtab_hdr, sym,
2679 NULL);
2680 (*_bfd_error_handler)
2681 (_("%B: relocation %s against STT_GNU_IFUNC "
2682 "symbol `%s' isn't handled by %s"), input_bfd,
2683 x86_64_elf_howto_table[r_type].name,
2684 name, __FUNCTION__);
2685 bfd_set_error (bfd_error_bad_value);
2686 return FALSE;
2688 case R_X86_64_32S:
2689 if (info->shared)
2690 abort ();
2691 goto do_relocation;
2693 case R_X86_64_64:
2694 if (rel->r_addend != 0)
2696 if (h->root.root.string)
2697 name = h->root.root.string;
2698 else
2699 name = bfd_elf_sym_name (input_bfd, symtab_hdr,
2700 sym, NULL);
2701 (*_bfd_error_handler)
2702 (_("%B: relocation %s against STT_GNU_IFUNC "
2703 "symbol `%s' has non-zero addend: %d"),
2704 input_bfd, x86_64_elf_howto_table[r_type].name,
2705 name, rel->r_addend);
2706 bfd_set_error (bfd_error_bad_value);
2707 return FALSE;
2710 /* Generate dynamic relcoation only when there is a
2711 non-GOF reference in a shared object. */
2712 if (info->shared && h->non_got_ref)
2714 Elf_Internal_Rela outrel;
2715 bfd_byte *loc;
2716 asection *sreloc;
2718 /* Need a dynamic relocation to get the real function
2719 address. */
2720 outrel.r_offset = _bfd_elf_section_offset (output_bfd,
2721 info,
2722 input_section,
2723 rel->r_offset);
2724 if (outrel.r_offset == (bfd_vma) -1
2725 || outrel.r_offset == (bfd_vma) -2)
2726 abort ();
2728 outrel.r_offset += (input_section->output_section->vma
2729 + input_section->output_offset);
2731 if (h->dynindx == -1
2732 || h->forced_local
2733 || info->executable)
2735 /* This symbol is resolved locally. */
2736 outrel.r_info = ELF64_R_INFO (0, R_X86_64_IRELATIVE);
2737 outrel.r_addend = (h->root.u.def.value
2738 + h->root.u.def.section->output_section->vma
2739 + h->root.u.def.section->output_offset);
2741 else
2743 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
2744 outrel.r_addend = 0;
2747 sreloc = htab->elf.irelifunc;
2748 loc = sreloc->contents;
2749 loc += (sreloc->reloc_count++
2750 * sizeof (Elf64_External_Rela));
2751 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2753 /* If this reloc is against an external symbol, we
2754 do not want to fiddle with the addend. Otherwise,
2755 we need to include the symbol value so that it
2756 becomes an addend for the dynamic reloc. For an
2757 internal symbol, we have updated addend. */
2758 continue;
2761 case R_X86_64_32:
2762 case R_X86_64_PC32:
2763 case R_X86_64_PC64:
2764 case R_X86_64_PLT32:
2765 goto do_relocation;
2767 case R_X86_64_GOTPCREL:
2768 case R_X86_64_GOTPCREL64:
2769 base_got = htab->elf.sgot;
2770 off = h->got.offset;
2772 if (base_got == NULL)
2773 abort ();
2775 if (off == (bfd_vma) -1)
2777 /* We can't use h->got.offset here to save state, or
2778 even just remember the offset, as finish_dynamic_symbol
2779 would use that as offset into .got. */
2781 if (htab->elf.splt != NULL)
2783 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2784 off = (plt_index + 3) * GOT_ENTRY_SIZE;
2785 base_got = htab->elf.sgotplt;
2787 else
2789 plt_index = h->plt.offset / PLT_ENTRY_SIZE;
2790 off = plt_index * GOT_ENTRY_SIZE;
2791 base_got = htab->elf.igotplt;
2794 if (h->dynindx == -1
2795 || h->forced_local
2796 || info->symbolic)
2798 /* This references the local defitionion. We must
2799 initialize this entry in the global offset table.
2800 Since the offset must always be a multiple of 8,
2801 we use the least significant bit to record
2802 whether we have initialized it already.
2804 When doing a dynamic link, we create a .rela.got
2805 relocation entry to initialize the value. This
2806 is done in the finish_dynamic_symbol routine. */
2807 if ((off & 1) != 0)
2808 off &= ~1;
2809 else
2811 bfd_put_64 (output_bfd, relocation,
2812 base_got->contents + off);
2813 /* Note that this is harmless for the GOTPLT64
2814 case, as -1 | 1 still is -1. */
2815 h->got.offset |= 1;
2820 relocation = (base_got->output_section->vma
2821 + base_got->output_offset + off);
2823 if (r_type != R_X86_64_GOTPCREL
2824 && r_type != R_X86_64_GOTPCREL64)
2826 asection *gotplt;
2827 if (htab->elf.splt != NULL)
2828 gotplt = htab->elf.sgotplt;
2829 else
2830 gotplt = htab->elf.igotplt;
2831 relocation -= (gotplt->output_section->vma
2832 - gotplt->output_offset);
2835 goto do_relocation;
2839 /* When generating a shared object, the relocations handled here are
2840 copied into the output file to be resolved at run time. */
2841 switch (r_type)
2843 case R_X86_64_GOT32:
2844 case R_X86_64_GOT64:
2845 /* Relocation is to the entry for this symbol in the global
2846 offset table. */
2847 case R_X86_64_GOTPCREL:
2848 case R_X86_64_GOTPCREL64:
2849 /* Use global offset table entry as symbol value. */
2850 case R_X86_64_GOTPLT64:
2851 /* This is the same as GOT64 for relocation purposes, but
2852 indicates the existence of a PLT entry. The difficulty is,
2853 that we must calculate the GOT slot offset from the PLT
2854 offset, if this symbol got a PLT entry (it was global).
2855 Additionally if it's computed from the PLT entry, then that
2856 GOT offset is relative to .got.plt, not to .got. */
2857 base_got = htab->elf.sgot;
2859 if (htab->elf.sgot == NULL)
2860 abort ();
2862 if (h != NULL)
2864 bfd_boolean dyn;
2866 off = h->got.offset;
2867 if (h->needs_plt
2868 && h->plt.offset != (bfd_vma)-1
2869 && off == (bfd_vma)-1)
2871 /* We can't use h->got.offset here to save
2872 state, or even just remember the offset, as
2873 finish_dynamic_symbol would use that as offset into
2874 .got. */
2875 bfd_vma plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2876 off = (plt_index + 3) * GOT_ENTRY_SIZE;
2877 base_got = htab->elf.sgotplt;
2880 dyn = htab->elf.dynamic_sections_created;
2882 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
2883 || (info->shared
2884 && SYMBOL_REFERENCES_LOCAL (info, h))
2885 || (ELF_ST_VISIBILITY (h->other)
2886 && h->root.type == bfd_link_hash_undefweak))
2888 /* This is actually a static link, or it is a -Bsymbolic
2889 link and the symbol is defined locally, or the symbol
2890 was forced to be local because of a version file. We
2891 must initialize this entry in the global offset table.
2892 Since the offset must always be a multiple of 8, we
2893 use the least significant bit to record whether we
2894 have initialized it already.
2896 When doing a dynamic link, we create a .rela.got
2897 relocation entry to initialize the value. This is
2898 done in the finish_dynamic_symbol routine. */
2899 if ((off & 1) != 0)
2900 off &= ~1;
2901 else
2903 bfd_put_64 (output_bfd, relocation,
2904 base_got->contents + off);
2905 /* Note that this is harmless for the GOTPLT64 case,
2906 as -1 | 1 still is -1. */
2907 h->got.offset |= 1;
2910 else
2911 unresolved_reloc = FALSE;
2913 else
2915 if (local_got_offsets == NULL)
2916 abort ();
2918 off = local_got_offsets[r_symndx];
2920 /* The offset must always be a multiple of 8. We use
2921 the least significant bit to record whether we have
2922 already generated the necessary reloc. */
2923 if ((off & 1) != 0)
2924 off &= ~1;
2925 else
2927 bfd_put_64 (output_bfd, relocation,
2928 base_got->contents + off);
2930 if (info->shared)
2932 asection *s;
2933 Elf_Internal_Rela outrel;
2934 bfd_byte *loc;
2936 /* We need to generate a R_X86_64_RELATIVE reloc
2937 for the dynamic linker. */
2938 s = htab->elf.srelgot;
2939 if (s == NULL)
2940 abort ();
2942 outrel.r_offset = (base_got->output_section->vma
2943 + base_got->output_offset
2944 + off);
2945 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
2946 outrel.r_addend = relocation;
2947 loc = s->contents;
2948 loc += s->reloc_count++ * sizeof (Elf64_External_Rela);
2949 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
2952 local_got_offsets[r_symndx] |= 1;
2956 if (off >= (bfd_vma) -2)
2957 abort ();
2959 relocation = base_got->output_section->vma
2960 + base_got->output_offset + off;
2961 if (r_type != R_X86_64_GOTPCREL && r_type != R_X86_64_GOTPCREL64)
2962 relocation -= htab->elf.sgotplt->output_section->vma
2963 - htab->elf.sgotplt->output_offset;
2965 break;
2967 case R_X86_64_GOTOFF64:
2968 /* Relocation is relative to the start of the global offset
2969 table. */
2971 /* Check to make sure it isn't a protected function symbol
2972 for shared library since it may not be local when used
2973 as function address. */
2974 if (info->shared
2975 && h
2976 && h->def_regular
2977 && h->type == STT_FUNC
2978 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
2980 (*_bfd_error_handler)
2981 (_("%B: relocation R_X86_64_GOTOFF64 against protected function `%s' can not be used when making a shared object"),
2982 input_bfd, h->root.root.string);
2983 bfd_set_error (bfd_error_bad_value);
2984 return FALSE;
2987 /* Note that sgot is not involved in this
2988 calculation. We always want the start of .got.plt. If we
2989 defined _GLOBAL_OFFSET_TABLE_ in a different way, as is
2990 permitted by the ABI, we might have to change this
2991 calculation. */
2992 relocation -= htab->elf.sgotplt->output_section->vma
2993 + htab->elf.sgotplt->output_offset;
2994 break;
2996 case R_X86_64_GOTPC32:
2997 case R_X86_64_GOTPC64:
2998 /* Use global offset table as symbol value. */
2999 relocation = htab->elf.sgotplt->output_section->vma
3000 + htab->elf.sgotplt->output_offset;
3001 unresolved_reloc = FALSE;
3002 break;
3004 case R_X86_64_PLTOFF64:
3005 /* Relocation is PLT entry relative to GOT. For local
3006 symbols it's the symbol itself relative to GOT. */
3007 if (h != NULL
3008 /* See PLT32 handling. */
3009 && h->plt.offset != (bfd_vma) -1
3010 && htab->elf.splt != NULL)
3012 relocation = (htab->elf.splt->output_section->vma
3013 + htab->elf.splt->output_offset
3014 + h->plt.offset);
3015 unresolved_reloc = FALSE;
3018 relocation -= htab->elf.sgotplt->output_section->vma
3019 + htab->elf.sgotplt->output_offset;
3020 break;
3022 case R_X86_64_PLT32:
3023 /* Relocation is to the entry for this symbol in the
3024 procedure linkage table. */
3026 /* Resolve a PLT32 reloc against a local symbol directly,
3027 without using the procedure linkage table. */
3028 if (h == NULL)
3029 break;
3031 if (h->plt.offset == (bfd_vma) -1
3032 || htab->elf.splt == NULL)
3034 /* We didn't make a PLT entry for this symbol. This
3035 happens when statically linking PIC code, or when
3036 using -Bsymbolic. */
3037 break;
3040 relocation = (htab->elf.splt->output_section->vma
3041 + htab->elf.splt->output_offset
3042 + h->plt.offset);
3043 unresolved_reloc = FALSE;
3044 break;
3046 case R_X86_64_PC8:
3047 case R_X86_64_PC16:
3048 case R_X86_64_PC32:
3049 if (info->shared
3050 && (input_section->flags & SEC_ALLOC) != 0
3051 && (input_section->flags & SEC_READONLY) != 0
3052 && h != NULL)
3054 bfd_boolean fail = FALSE;
3055 bfd_boolean branch
3056 = (r_type == R_X86_64_PC32
3057 && is_32bit_relative_branch (contents, rel->r_offset));
3059 if (SYMBOL_REFERENCES_LOCAL (info, h))
3061 /* Symbol is referenced locally. Make sure it is
3062 defined locally or for a branch. */
3063 fail = !h->def_regular && !branch;
3065 else
3067 /* Symbol isn't referenced locally. We only allow
3068 branch to symbol with non-default visibility. */
3069 fail = (!branch
3070 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT);
3073 if (fail)
3075 const char *fmt;
3076 const char *v;
3077 const char *pic = "";
3079 switch (ELF_ST_VISIBILITY (h->other))
3081 case STV_HIDDEN:
3082 v = _("hidden symbol");
3083 break;
3084 case STV_INTERNAL:
3085 v = _("internal symbol");
3086 break;
3087 case STV_PROTECTED:
3088 v = _("protected symbol");
3089 break;
3090 default:
3091 v = _("symbol");
3092 pic = _("; recompile with -fPIC");
3093 break;
3096 if (h->def_regular)
3097 fmt = _("%B: relocation %s against %s `%s' can not be used when making a shared object%s");
3098 else
3099 fmt = _("%B: relocation %s against undefined %s `%s' can not be used when making a shared object%s");
3101 (*_bfd_error_handler) (fmt, input_bfd,
3102 x86_64_elf_howto_table[r_type].name,
3103 v, h->root.root.string, pic);
3104 bfd_set_error (bfd_error_bad_value);
3105 return FALSE;
3108 /* Fall through. */
3110 case R_X86_64_8:
3111 case R_X86_64_16:
3112 case R_X86_64_32:
3113 case R_X86_64_PC64:
3114 case R_X86_64_64:
3115 /* FIXME: The ABI says the linker should make sure the value is
3116 the same when it's zeroextended to 64 bit. */
3118 if ((input_section->flags & SEC_ALLOC) == 0)
3119 break;
3121 if ((info->shared
3122 && (h == NULL
3123 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
3124 || h->root.type != bfd_link_hash_undefweak)
3125 && (! IS_X86_64_PCREL_TYPE (r_type)
3126 || ! SYMBOL_CALLS_LOCAL (info, h)))
3127 || (ELIMINATE_COPY_RELOCS
3128 && !info->shared
3129 && h != NULL
3130 && h->dynindx != -1
3131 && !h->non_got_ref
3132 && ((h->def_dynamic
3133 && !h->def_regular)
3134 || h->root.type == bfd_link_hash_undefweak
3135 || h->root.type == bfd_link_hash_undefined)))
3137 Elf_Internal_Rela outrel;
3138 bfd_byte *loc;
3139 bfd_boolean skip, relocate;
3140 asection *sreloc;
3142 /* When generating a shared object, these relocations
3143 are copied into the output file to be resolved at run
3144 time. */
3145 skip = FALSE;
3146 relocate = FALSE;
3148 outrel.r_offset =
3149 _bfd_elf_section_offset (output_bfd, info, input_section,
3150 rel->r_offset);
3151 if (outrel.r_offset == (bfd_vma) -1)
3152 skip = TRUE;
3153 else if (outrel.r_offset == (bfd_vma) -2)
3154 skip = TRUE, relocate = TRUE;
3156 outrel.r_offset += (input_section->output_section->vma
3157 + input_section->output_offset);
3159 if (skip)
3160 memset (&outrel, 0, sizeof outrel);
3162 /* h->dynindx may be -1 if this symbol was marked to
3163 become local. */
3164 else if (h != NULL
3165 && h->dynindx != -1
3166 && (IS_X86_64_PCREL_TYPE (r_type)
3167 || ! info->shared
3168 || ! SYMBOLIC_BIND (info, h)
3169 || ! h->def_regular))
3171 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
3172 outrel.r_addend = rel->r_addend;
3174 else
3176 /* This symbol is local, or marked to become local. */
3177 if (r_type == R_X86_64_64)
3179 relocate = TRUE;
3180 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
3181 outrel.r_addend = relocation + rel->r_addend;
3183 else
3185 long sindx;
3187 if (bfd_is_abs_section (sec))
3188 sindx = 0;
3189 else if (sec == NULL || sec->owner == NULL)
3191 bfd_set_error (bfd_error_bad_value);
3192 return FALSE;
3194 else
3196 asection *osec;
3198 /* We are turning this relocation into one
3199 against a section symbol. It would be
3200 proper to subtract the symbol's value,
3201 osec->vma, from the emitted reloc addend,
3202 but ld.so expects buggy relocs. */
3203 osec = sec->output_section;
3204 sindx = elf_section_data (osec)->dynindx;
3205 if (sindx == 0)
3207 asection *oi = htab->elf.text_index_section;
3208 sindx = elf_section_data (oi)->dynindx;
3210 BFD_ASSERT (sindx != 0);
3213 outrel.r_info = ELF64_R_INFO (sindx, r_type);
3214 outrel.r_addend = relocation + rel->r_addend;
3218 sreloc = elf_section_data (input_section)->sreloc;
3220 BFD_ASSERT (sreloc != NULL && sreloc->contents != NULL);
3222 loc = sreloc->contents;
3223 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
3224 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
3226 /* If this reloc is against an external symbol, we do
3227 not want to fiddle with the addend. Otherwise, we
3228 need to include the symbol value so that it becomes
3229 an addend for the dynamic reloc. */
3230 if (! relocate)
3231 continue;
3234 break;
3236 case R_X86_64_TLSGD:
3237 case R_X86_64_GOTPC32_TLSDESC:
3238 case R_X86_64_TLSDESC_CALL:
3239 case R_X86_64_GOTTPOFF:
3240 tls_type = GOT_UNKNOWN;
3241 if (h == NULL && local_got_offsets)
3242 tls_type = elf64_x86_64_local_got_tls_type (input_bfd) [r_symndx];
3243 else if (h != NULL)
3244 tls_type = elf64_x86_64_hash_entry (h)->tls_type;
3246 if (! elf64_x86_64_tls_transition (info, input_bfd,
3247 input_section, contents,
3248 symtab_hdr, sym_hashes,
3249 &r_type, tls_type, rel,
3250 relend, h, r_symndx))
3251 return FALSE;
3253 if (r_type == R_X86_64_TPOFF32)
3255 bfd_vma roff = rel->r_offset;
3257 BFD_ASSERT (! unresolved_reloc);
3259 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
3261 /* GD->LE transition.
3262 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
3263 .word 0x6666; rex64; call __tls_get_addr
3264 Change it into:
3265 movq %fs:0, %rax
3266 leaq foo@tpoff(%rax), %rax */
3267 memcpy (contents + roff - 4,
3268 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0",
3269 16);
3270 bfd_put_32 (output_bfd,
3271 elf64_x86_64_tpoff (info, relocation),
3272 contents + roff + 8);
3273 /* Skip R_X86_64_PC32/R_X86_64_PLT32. */
3274 rel++;
3275 continue;
3277 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTPC32_TLSDESC)
3279 /* GDesc -> LE transition.
3280 It's originally something like:
3281 leaq x@tlsdesc(%rip), %rax
3283 Change it to:
3284 movl $x@tpoff, %rax
3287 unsigned int val, type, type2;
3289 type = bfd_get_8 (input_bfd, contents + roff - 3);
3290 type2 = bfd_get_8 (input_bfd, contents + roff - 2);
3291 val = bfd_get_8 (input_bfd, contents + roff - 1);
3292 bfd_put_8 (output_bfd, 0x48 | ((type >> 2) & 1),
3293 contents + roff - 3);
3294 bfd_put_8 (output_bfd, 0xc7, contents + roff - 2);
3295 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7),
3296 contents + roff - 1);
3297 bfd_put_32 (output_bfd,
3298 elf64_x86_64_tpoff (info, relocation),
3299 contents + roff);
3300 continue;
3302 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSDESC_CALL)
3304 /* GDesc -> LE transition.
3305 It's originally:
3306 call *(%rax)
3307 Turn it into:
3308 xchg %ax,%ax. */
3309 bfd_put_8 (output_bfd, 0x66, contents + roff);
3310 bfd_put_8 (output_bfd, 0x90, contents + roff + 1);
3311 continue;
3313 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTTPOFF)
3315 /* IE->LE transition:
3316 Originally it can be one of:
3317 movq foo@gottpoff(%rip), %reg
3318 addq foo@gottpoff(%rip), %reg
3319 We change it into:
3320 movq $foo, %reg
3321 leaq foo(%reg), %reg
3322 addq $foo, %reg. */
3324 unsigned int val, type, reg;
3326 val = bfd_get_8 (input_bfd, contents + roff - 3);
3327 type = bfd_get_8 (input_bfd, contents + roff - 2);
3328 reg = bfd_get_8 (input_bfd, contents + roff - 1);
3329 reg >>= 3;
3330 if (type == 0x8b)
3332 /* movq */
3333 if (val == 0x4c)
3334 bfd_put_8 (output_bfd, 0x49,
3335 contents + roff - 3);
3336 bfd_put_8 (output_bfd, 0xc7,
3337 contents + roff - 2);
3338 bfd_put_8 (output_bfd, 0xc0 | reg,
3339 contents + roff - 1);
3341 else if (reg == 4)
3343 /* addq -> addq - addressing with %rsp/%r12 is
3344 special */
3345 if (val == 0x4c)
3346 bfd_put_8 (output_bfd, 0x49,
3347 contents + roff - 3);
3348 bfd_put_8 (output_bfd, 0x81,
3349 contents + roff - 2);
3350 bfd_put_8 (output_bfd, 0xc0 | reg,
3351 contents + roff - 1);
3353 else
3355 /* addq -> leaq */
3356 if (val == 0x4c)
3357 bfd_put_8 (output_bfd, 0x4d,
3358 contents + roff - 3);
3359 bfd_put_8 (output_bfd, 0x8d,
3360 contents + roff - 2);
3361 bfd_put_8 (output_bfd, 0x80 | reg | (reg << 3),
3362 contents + roff - 1);
3364 bfd_put_32 (output_bfd,
3365 elf64_x86_64_tpoff (info, relocation),
3366 contents + roff);
3367 continue;
3369 else
3370 BFD_ASSERT (FALSE);
3373 if (htab->elf.sgot == NULL)
3374 abort ();
3376 if (h != NULL)
3378 off = h->got.offset;
3379 offplt = elf64_x86_64_hash_entry (h)->tlsdesc_got;
3381 else
3383 if (local_got_offsets == NULL)
3384 abort ();
3386 off = local_got_offsets[r_symndx];
3387 offplt = local_tlsdesc_gotents[r_symndx];
3390 if ((off & 1) != 0)
3391 off &= ~1;
3392 else
3394 Elf_Internal_Rela outrel;
3395 bfd_byte *loc;
3396 int dr_type, indx;
3397 asection *sreloc;
3399 if (htab->elf.srelgot == NULL)
3400 abort ();
3402 indx = h && h->dynindx != -1 ? h->dynindx : 0;
3404 if (GOT_TLS_GDESC_P (tls_type))
3406 outrel.r_info = ELF64_R_INFO (indx, R_X86_64_TLSDESC);
3407 BFD_ASSERT (htab->sgotplt_jump_table_size + offplt
3408 + 2 * GOT_ENTRY_SIZE <= htab->elf.sgotplt->size);
3409 outrel.r_offset = (htab->elf.sgotplt->output_section->vma
3410 + htab->elf.sgotplt->output_offset
3411 + offplt
3412 + htab->sgotplt_jump_table_size);
3413 sreloc = htab->elf.srelplt;
3414 loc = sreloc->contents;
3415 loc += sreloc->reloc_count++
3416 * sizeof (Elf64_External_Rela);
3417 BFD_ASSERT (loc + sizeof (Elf64_External_Rela)
3418 <= sreloc->contents + sreloc->size);
3419 if (indx == 0)
3420 outrel.r_addend = relocation - elf64_x86_64_dtpoff_base (info);
3421 else
3422 outrel.r_addend = 0;
3423 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
3426 sreloc = htab->elf.srelgot;
3428 outrel.r_offset = (htab->elf.sgot->output_section->vma
3429 + htab->elf.sgot->output_offset + off);
3431 if (GOT_TLS_GD_P (tls_type))
3432 dr_type = R_X86_64_DTPMOD64;
3433 else if (GOT_TLS_GDESC_P (tls_type))
3434 goto dr_done;
3435 else
3436 dr_type = R_X86_64_TPOFF64;
3438 bfd_put_64 (output_bfd, 0, htab->elf.sgot->contents + off);
3439 outrel.r_addend = 0;
3440 if ((dr_type == R_X86_64_TPOFF64
3441 || dr_type == R_X86_64_TLSDESC) && indx == 0)
3442 outrel.r_addend = relocation - elf64_x86_64_dtpoff_base (info);
3443 outrel.r_info = ELF64_R_INFO (indx, dr_type);
3445 loc = sreloc->contents;
3446 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
3447 BFD_ASSERT (loc + sizeof (Elf64_External_Rela)
3448 <= sreloc->contents + sreloc->size);
3449 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
3451 if (GOT_TLS_GD_P (tls_type))
3453 if (indx == 0)
3455 BFD_ASSERT (! unresolved_reloc);
3456 bfd_put_64 (output_bfd,
3457 relocation - elf64_x86_64_dtpoff_base (info),
3458 htab->elf.sgot->contents + off + GOT_ENTRY_SIZE);
3460 else
3462 bfd_put_64 (output_bfd, 0,
3463 htab->elf.sgot->contents + off + GOT_ENTRY_SIZE);
3464 outrel.r_info = ELF64_R_INFO (indx,
3465 R_X86_64_DTPOFF64);
3466 outrel.r_offset += GOT_ENTRY_SIZE;
3467 sreloc->reloc_count++;
3468 loc += sizeof (Elf64_External_Rela);
3469 BFD_ASSERT (loc + sizeof (Elf64_External_Rela)
3470 <= sreloc->contents + sreloc->size);
3471 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
3475 dr_done:
3476 if (h != NULL)
3477 h->got.offset |= 1;
3478 else
3479 local_got_offsets[r_symndx] |= 1;
3482 if (off >= (bfd_vma) -2
3483 && ! GOT_TLS_GDESC_P (tls_type))
3484 abort ();
3485 if (r_type == ELF64_R_TYPE (rel->r_info))
3487 if (r_type == R_X86_64_GOTPC32_TLSDESC
3488 || r_type == R_X86_64_TLSDESC_CALL)
3489 relocation = htab->elf.sgotplt->output_section->vma
3490 + htab->elf.sgotplt->output_offset
3491 + offplt + htab->sgotplt_jump_table_size;
3492 else
3493 relocation = htab->elf.sgot->output_section->vma
3494 + htab->elf.sgot->output_offset + off;
3495 unresolved_reloc = FALSE;
3497 else
3499 bfd_vma roff = rel->r_offset;
3501 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD)
3503 /* GD->IE transition.
3504 .byte 0x66; leaq foo@tlsgd(%rip), %rdi
3505 .word 0x6666; rex64; call __tls_get_addr@plt
3506 Change it into:
3507 movq %fs:0, %rax
3508 addq foo@gottpoff(%rip), %rax */
3509 memcpy (contents + roff - 4,
3510 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0",
3511 16);
3513 relocation = (htab->elf.sgot->output_section->vma
3514 + htab->elf.sgot->output_offset + off
3515 - roff
3516 - input_section->output_section->vma
3517 - input_section->output_offset
3518 - 12);
3519 bfd_put_32 (output_bfd, relocation,
3520 contents + roff + 8);
3521 /* Skip R_X86_64_PLT32. */
3522 rel++;
3523 continue;
3525 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTPC32_TLSDESC)
3527 /* GDesc -> IE transition.
3528 It's originally something like:
3529 leaq x@tlsdesc(%rip), %rax
3531 Change it to:
3532 movq x@gottpoff(%rip), %rax # before xchg %ax,%ax
3535 unsigned int val, type, type2;
3537 type = bfd_get_8 (input_bfd, contents + roff - 3);
3538 type2 = bfd_get_8 (input_bfd, contents + roff - 2);
3539 val = bfd_get_8 (input_bfd, contents + roff - 1);
3541 /* Now modify the instruction as appropriate. To
3542 turn a leaq into a movq in the form we use it, it
3543 suffices to change the second byte from 0x8d to
3544 0x8b. */
3545 bfd_put_8 (output_bfd, 0x8b, contents + roff - 2);
3547 bfd_put_32 (output_bfd,
3548 htab->elf.sgot->output_section->vma
3549 + htab->elf.sgot->output_offset + off
3550 - rel->r_offset
3551 - input_section->output_section->vma
3552 - input_section->output_offset
3553 - 4,
3554 contents + roff);
3555 continue;
3557 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSDESC_CALL)
3559 /* GDesc -> IE transition.
3560 It's originally:
3561 call *(%rax)
3563 Change it to:
3564 xchg %ax,%ax. */
3566 unsigned int val, type;
3568 type = bfd_get_8 (input_bfd, contents + roff);
3569 val = bfd_get_8 (input_bfd, contents + roff + 1);
3570 bfd_put_8 (output_bfd, 0x66, contents + roff);
3571 bfd_put_8 (output_bfd, 0x90, contents + roff + 1);
3572 continue;
3574 else
3575 BFD_ASSERT (FALSE);
3577 break;
3579 case R_X86_64_TLSLD:
3580 if (! elf64_x86_64_tls_transition (info, input_bfd,
3581 input_section, contents,
3582 symtab_hdr, sym_hashes,
3583 &r_type, GOT_UNKNOWN,
3584 rel, relend, h, r_symndx))
3585 return FALSE;
3587 if (r_type != R_X86_64_TLSLD)
3589 /* LD->LE transition:
3590 leaq foo@tlsld(%rip), %rdi; call __tls_get_addr.
3591 We change it into:
3592 .word 0x6666; .byte 0x66; movl %fs:0, %rax. */
3594 BFD_ASSERT (r_type == R_X86_64_TPOFF32);
3595 memcpy (contents + rel->r_offset - 3,
3596 "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0", 12);
3597 /* Skip R_X86_64_PC32/R_X86_64_PLT32. */
3598 rel++;
3599 continue;
3602 if (htab->elf.sgot == NULL)
3603 abort ();
3605 off = htab->tls_ld_got.offset;
3606 if (off & 1)
3607 off &= ~1;
3608 else
3610 Elf_Internal_Rela outrel;
3611 bfd_byte *loc;
3613 if (htab->elf.srelgot == NULL)
3614 abort ();
3616 outrel.r_offset = (htab->elf.sgot->output_section->vma
3617 + htab->elf.sgot->output_offset + off);
3619 bfd_put_64 (output_bfd, 0,
3620 htab->elf.sgot->contents + off);
3621 bfd_put_64 (output_bfd, 0,
3622 htab->elf.sgot->contents + off + GOT_ENTRY_SIZE);
3623 outrel.r_info = ELF64_R_INFO (0, R_X86_64_DTPMOD64);
3624 outrel.r_addend = 0;
3625 loc = htab->elf.srelgot->contents;
3626 loc += htab->elf.srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
3627 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
3628 htab->tls_ld_got.offset |= 1;
3630 relocation = htab->elf.sgot->output_section->vma
3631 + htab->elf.sgot->output_offset + off;
3632 unresolved_reloc = FALSE;
3633 break;
3635 case R_X86_64_DTPOFF32:
3636 if (!info->executable|| (input_section->flags & SEC_CODE) == 0)
3637 relocation -= elf64_x86_64_dtpoff_base (info);
3638 else
3639 relocation = elf64_x86_64_tpoff (info, relocation);
3640 break;
3642 case R_X86_64_TPOFF32:
3643 BFD_ASSERT (info->executable);
3644 relocation = elf64_x86_64_tpoff (info, relocation);
3645 break;
3647 default:
3648 break;
3651 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
3652 because such sections are not SEC_ALLOC and thus ld.so will
3653 not process them. */
3654 if (unresolved_reloc
3655 && !((input_section->flags & SEC_DEBUGGING) != 0
3656 && h->def_dynamic))
3657 (*_bfd_error_handler)
3658 (_("%B(%A+0x%lx): unresolvable %s relocation against symbol `%s'"),
3659 input_bfd,
3660 input_section,
3661 (long) rel->r_offset,
3662 howto->name,
3663 h->root.root.string);
3665 do_relocation:
3666 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
3667 contents, rel->r_offset,
3668 relocation, rel->r_addend);
3670 if (r != bfd_reloc_ok)
3672 const char *name;
3674 if (h != NULL)
3675 name = h->root.root.string;
3676 else
3678 name = bfd_elf_string_from_elf_section (input_bfd,
3679 symtab_hdr->sh_link,
3680 sym->st_name);
3681 if (name == NULL)
3682 return FALSE;
3683 if (*name == '\0')
3684 name = bfd_section_name (input_bfd, sec);
3687 if (r == bfd_reloc_overflow)
3689 if (! ((*info->callbacks->reloc_overflow)
3690 (info, (h ? &h->root : NULL), name, howto->name,
3691 (bfd_vma) 0, input_bfd, input_section,
3692 rel->r_offset)))
3693 return FALSE;
3695 else
3697 (*_bfd_error_handler)
3698 (_("%B(%A+0x%lx): reloc against `%s': error %d"),
3699 input_bfd, input_section,
3700 (long) rel->r_offset, name, (int) r);
3701 return FALSE;
3706 return TRUE;
3709 /* Finish up dynamic symbol handling. We set the contents of various
3710 dynamic sections here. */
3712 static bfd_boolean
3713 elf64_x86_64_finish_dynamic_symbol (bfd *output_bfd,
3714 struct bfd_link_info *info,
3715 struct elf_link_hash_entry *h,
3716 Elf_Internal_Sym *sym)
3718 struct elf64_x86_64_link_hash_table *htab;
3720 htab = elf64_x86_64_hash_table (info);
3722 if (h->plt.offset != (bfd_vma) -1)
3724 bfd_vma plt_index;
3725 bfd_vma got_offset;
3726 Elf_Internal_Rela rela;
3727 bfd_byte *loc;
3728 asection *plt, *gotplt, *relplt;
3730 /* When building a static executable, use .iplt, .igot.plt and
3731 .rela.iplt sections for STT_GNU_IFUNC symbols. */
3732 if (htab->elf.splt != NULL)
3734 plt = htab->elf.splt;
3735 gotplt = htab->elf.sgotplt;
3736 relplt = htab->elf.srelplt;
3738 else
3740 plt = htab->elf.iplt;
3741 gotplt = htab->elf.igotplt;
3742 relplt = htab->elf.irelplt;
3745 /* This symbol has an entry in the procedure linkage table. Set
3746 it up. */
3747 if ((h->dynindx == -1
3748 && !((h->forced_local || info->executable)
3749 && h->def_regular
3750 && h->type == STT_GNU_IFUNC))
3751 || plt == NULL
3752 || gotplt == NULL
3753 || relplt == NULL)
3754 abort ();
3756 /* Get the index in the procedure linkage table which
3757 corresponds to this symbol. This is the index of this symbol
3758 in all the symbols for which we are making plt entries. The
3759 first entry in the procedure linkage table is reserved.
3761 Get the offset into the .got table of the entry that
3762 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE
3763 bytes. The first three are reserved for the dynamic linker.
3765 For static executables, we don't reserve anything. */
3767 if (plt == htab->elf.splt)
3769 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
3770 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
3772 else
3774 plt_index = h->plt.offset / PLT_ENTRY_SIZE;
3775 got_offset = plt_index * GOT_ENTRY_SIZE;
3778 /* Fill in the entry in the procedure linkage table. */
3779 memcpy (plt->contents + h->plt.offset, elf64_x86_64_plt_entry,
3780 PLT_ENTRY_SIZE);
3782 /* Insert the relocation positions of the plt section. The magic
3783 numbers at the end of the statements are the positions of the
3784 relocations in the plt section. */
3785 /* Put offset for jmp *name@GOTPCREL(%rip), since the
3786 instruction uses 6 bytes, subtract this value. */
3787 bfd_put_32 (output_bfd,
3788 (gotplt->output_section->vma
3789 + gotplt->output_offset
3790 + got_offset
3791 - plt->output_section->vma
3792 - plt->output_offset
3793 - h->plt.offset
3794 - 6),
3795 plt->contents + h->plt.offset + 2);
3797 /* Don't fill PLT entry for static executables. */
3798 if (plt == htab->elf.splt)
3800 /* Put relocation index. */
3801 bfd_put_32 (output_bfd, plt_index,
3802 plt->contents + h->plt.offset + 7);
3803 /* Put offset for jmp .PLT0. */
3804 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
3805 plt->contents + h->plt.offset + 12);
3808 /* Fill in the entry in the global offset table, initially this
3809 points to the pushq instruction in the PLT which is at offset 6. */
3810 bfd_put_64 (output_bfd, (plt->output_section->vma
3811 + plt->output_offset
3812 + h->plt.offset + 6),
3813 gotplt->contents + got_offset);
3815 /* Fill in the entry in the .rela.plt section. */
3816 rela.r_offset = (gotplt->output_section->vma
3817 + gotplt->output_offset
3818 + got_offset);
3819 if (h->dynindx == -1
3820 || ((info->executable
3821 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
3822 && h->def_regular
3823 && h->type == STT_GNU_IFUNC))
3825 /* If an STT_GNU_IFUNC symbol is locally defined, generate
3826 R_X86_64_IRELATIVE instead of R_X86_64_JUMP_SLOT. */
3827 rela.r_info = ELF64_R_INFO (0, R_X86_64_IRELATIVE);
3828 rela.r_addend = (h->root.u.def.value
3829 + h->root.u.def.section->output_section->vma
3830 + h->root.u.def.section->output_offset);
3832 else
3834 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT);
3835 rela.r_addend = 0;
3837 loc = relplt->contents + plt_index * sizeof (Elf64_External_Rela);
3838 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
3840 if (!h->def_regular)
3842 /* Mark the symbol as undefined, rather than as defined in
3843 the .plt section. Leave the value if there were any
3844 relocations where pointer equality matters (this is a clue
3845 for the dynamic linker, to make function pointer
3846 comparisons work between an application and shared
3847 library), otherwise set it to zero. If a function is only
3848 called from a binary, there is no need to slow down
3849 shared libraries because of that. */
3850 sym->st_shndx = SHN_UNDEF;
3851 if (!h->pointer_equality_needed)
3852 sym->st_value = 0;
3856 if (h->got.offset != (bfd_vma) -1
3857 && ! GOT_TLS_GD_ANY_P (elf64_x86_64_hash_entry (h)->tls_type)
3858 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE)
3860 Elf_Internal_Rela rela;
3861 bfd_byte *loc;
3863 /* This symbol has an entry in the global offset table. Set it
3864 up. */
3865 if (htab->elf.sgot == NULL || htab->elf.srelgot == NULL)
3866 abort ();
3868 rela.r_offset = (htab->elf.sgot->output_section->vma
3869 + htab->elf.sgot->output_offset
3870 + (h->got.offset &~ (bfd_vma) 1));
3872 /* If this is a static link, or it is a -Bsymbolic link and the
3873 symbol is defined locally or was forced to be local because
3874 of a version file, we just want to emit a RELATIVE reloc.
3875 The entry in the global offset table will already have been
3876 initialized in the relocate_section function. */
3877 if (h->def_regular
3878 && h->type == STT_GNU_IFUNC)
3880 if (info->shared)
3882 /* Generate R_X86_64_GLOB_DAT. */
3883 goto do_glob_dat;
3885 else
3887 asection *plt;
3889 if (!h->pointer_equality_needed)
3890 abort ();
3892 /* For non-shared object, we can't use .got.plt, which
3893 contains the real function addres if we need pointer
3894 equality. We load the GOT entry with the PLT entry. */
3895 plt = htab->elf.splt ? htab->elf.splt : htab->elf.iplt;
3896 bfd_put_64 (output_bfd, (plt->output_section->vma
3897 + plt->output_offset
3898 + h->plt.offset),
3899 htab->elf.sgot->contents + h->got.offset);
3900 return TRUE;
3903 else if (info->shared
3904 && SYMBOL_REFERENCES_LOCAL (info, h))
3906 if (!h->def_regular)
3907 return FALSE;
3908 BFD_ASSERT((h->got.offset & 1) != 0);
3909 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
3910 rela.r_addend = (h->root.u.def.value
3911 + h->root.u.def.section->output_section->vma
3912 + h->root.u.def.section->output_offset);
3914 else
3916 BFD_ASSERT((h->got.offset & 1) == 0);
3917 do_glob_dat:
3918 bfd_put_64 (output_bfd, (bfd_vma) 0,
3919 htab->elf.sgot->contents + h->got.offset);
3920 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT);
3921 rela.r_addend = 0;
3924 loc = htab->elf.srelgot->contents;
3925 loc += htab->elf.srelgot->reloc_count++ * sizeof (Elf64_External_Rela);
3926 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
3929 if (h->needs_copy)
3931 Elf_Internal_Rela rela;
3932 bfd_byte *loc;
3934 /* This symbol needs a copy reloc. Set it up. */
3936 if (h->dynindx == -1
3937 || (h->root.type != bfd_link_hash_defined
3938 && h->root.type != bfd_link_hash_defweak)
3939 || htab->srelbss == NULL)
3940 abort ();
3942 rela.r_offset = (h->root.u.def.value
3943 + h->root.u.def.section->output_section->vma
3944 + h->root.u.def.section->output_offset);
3945 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY);
3946 rela.r_addend = 0;
3947 loc = htab->srelbss->contents;
3948 loc += htab->srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
3949 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
3952 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. SYM may
3953 be NULL for local symbols. */
3954 if (sym != NULL
3955 && (strcmp (h->root.root.string, "_DYNAMIC") == 0
3956 || h == htab->elf.hgot))
3957 sym->st_shndx = SHN_ABS;
3959 return TRUE;
3962 /* Finish up local dynamic symbol handling. We set the contents of
3963 various dynamic sections here. */
3965 static bfd_boolean
3966 elf64_x86_64_finish_local_dynamic_symbol (void **slot, void *inf)
3968 struct elf_link_hash_entry *h
3969 = (struct elf_link_hash_entry *) *slot;
3970 struct bfd_link_info *info
3971 = (struct bfd_link_info *) inf;
3973 return elf64_x86_64_finish_dynamic_symbol (info->output_bfd,
3974 info, h, NULL);
3977 /* Used to decide how to sort relocs in an optimal manner for the
3978 dynamic linker, before writing them out. */
3980 static enum elf_reloc_type_class
3981 elf64_x86_64_reloc_type_class (const Elf_Internal_Rela *rela)
3983 switch ((int) ELF64_R_TYPE (rela->r_info))
3985 case R_X86_64_RELATIVE:
3986 return reloc_class_relative;
3987 case R_X86_64_JUMP_SLOT:
3988 return reloc_class_plt;
3989 case R_X86_64_COPY:
3990 return reloc_class_copy;
3991 default:
3992 return reloc_class_normal;
3996 /* Finish up the dynamic sections. */
3998 static bfd_boolean
3999 elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
4001 struct elf64_x86_64_link_hash_table *htab;
4002 bfd *dynobj;
4003 asection *sdyn;
4005 htab = elf64_x86_64_hash_table (info);
4006 dynobj = htab->elf.dynobj;
4007 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
4009 if (htab->elf.dynamic_sections_created)
4011 Elf64_External_Dyn *dyncon, *dynconend;
4013 if (sdyn == NULL || htab->elf.sgot == NULL)
4014 abort ();
4016 dyncon = (Elf64_External_Dyn *) sdyn->contents;
4017 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->size);
4018 for (; dyncon < dynconend; dyncon++)
4020 Elf_Internal_Dyn dyn;
4021 asection *s;
4023 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
4025 switch (dyn.d_tag)
4027 default:
4028 continue;
4030 case DT_PLTGOT:
4031 s = htab->elf.sgotplt;
4032 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
4033 break;
4035 case DT_JMPREL:
4036 dyn.d_un.d_ptr = htab->elf.srelplt->output_section->vma;
4037 break;
4039 case DT_PLTRELSZ:
4040 s = htab->elf.srelplt->output_section;
4041 dyn.d_un.d_val = s->size;
4042 break;
4044 case DT_RELASZ:
4045 /* The procedure linkage table relocs (DT_JMPREL) should
4046 not be included in the overall relocs (DT_RELA).
4047 Therefore, we override the DT_RELASZ entry here to
4048 make it not include the JMPREL relocs. Since the
4049 linker script arranges for .rela.plt to follow all
4050 other relocation sections, we don't have to worry
4051 about changing the DT_RELA entry. */
4052 if (htab->elf.srelplt != NULL)
4054 s = htab->elf.srelplt->output_section;
4055 dyn.d_un.d_val -= s->size;
4057 break;
4059 case DT_TLSDESC_PLT:
4060 s = htab->elf.splt;
4061 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset
4062 + htab->tlsdesc_plt;
4063 break;
4065 case DT_TLSDESC_GOT:
4066 s = htab->elf.sgot;
4067 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset
4068 + htab->tlsdesc_got;
4069 break;
4072 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
4075 /* Fill in the special first entry in the procedure linkage table. */
4076 if (htab->elf.splt && htab->elf.splt->size > 0)
4078 /* Fill in the first entry in the procedure linkage table. */
4079 memcpy (htab->elf.splt->contents, elf64_x86_64_plt0_entry,
4080 PLT_ENTRY_SIZE);
4081 /* Add offset for pushq GOT+8(%rip), since the instruction
4082 uses 6 bytes subtract this value. */
4083 bfd_put_32 (output_bfd,
4084 (htab->elf.sgotplt->output_section->vma
4085 + htab->elf.sgotplt->output_offset
4087 - htab->elf.splt->output_section->vma
4088 - htab->elf.splt->output_offset
4089 - 6),
4090 htab->elf.splt->contents + 2);
4091 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to
4092 the end of the instruction. */
4093 bfd_put_32 (output_bfd,
4094 (htab->elf.sgotplt->output_section->vma
4095 + htab->elf.sgotplt->output_offset
4096 + 16
4097 - htab->elf.splt->output_section->vma
4098 - htab->elf.splt->output_offset
4099 - 12),
4100 htab->elf.splt->contents + 8);
4102 elf_section_data (htab->elf.splt->output_section)->this_hdr.sh_entsize =
4103 PLT_ENTRY_SIZE;
4105 if (htab->tlsdesc_plt)
4107 bfd_put_64 (output_bfd, (bfd_vma) 0,
4108 htab->elf.sgot->contents + htab->tlsdesc_got);
4110 memcpy (htab->elf.splt->contents + htab->tlsdesc_plt,
4111 elf64_x86_64_plt0_entry,
4112 PLT_ENTRY_SIZE);
4114 /* Add offset for pushq GOT+8(%rip), since the
4115 instruction uses 6 bytes subtract this value. */
4116 bfd_put_32 (output_bfd,
4117 (htab->elf.sgotplt->output_section->vma
4118 + htab->elf.sgotplt->output_offset
4120 - htab->elf.splt->output_section->vma
4121 - htab->elf.splt->output_offset
4122 - htab->tlsdesc_plt
4123 - 6),
4124 htab->elf.splt->contents + htab->tlsdesc_plt + 2);
4125 /* Add offset for jmp *GOT+TDG(%rip), where TGD stands for
4126 htab->tlsdesc_got. The 12 is the offset to the end of
4127 the instruction. */
4128 bfd_put_32 (output_bfd,
4129 (htab->elf.sgot->output_section->vma
4130 + htab->elf.sgot->output_offset
4131 + htab->tlsdesc_got
4132 - htab->elf.splt->output_section->vma
4133 - htab->elf.splt->output_offset
4134 - htab->tlsdesc_plt
4135 - 12),
4136 htab->elf.splt->contents + htab->tlsdesc_plt + 8);
4141 if (htab->elf.sgotplt)
4143 /* Fill in the first three entries in the global offset table. */
4144 if (htab->elf.sgotplt->size > 0)
4146 /* Set the first entry in the global offset table to the address of
4147 the dynamic section. */
4148 if (sdyn == NULL)
4149 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->elf.sgotplt->contents);
4150 else
4151 bfd_put_64 (output_bfd,
4152 sdyn->output_section->vma + sdyn->output_offset,
4153 htab->elf.sgotplt->contents);
4154 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */
4155 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->elf.sgotplt->contents + GOT_ENTRY_SIZE);
4156 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->elf.sgotplt->contents + GOT_ENTRY_SIZE*2);
4159 elf_section_data (htab->elf.sgotplt->output_section)->this_hdr.sh_entsize =
4160 GOT_ENTRY_SIZE;
4163 if (htab->elf.sgot && htab->elf.sgot->size > 0)
4164 elf_section_data (htab->elf.sgot->output_section)->this_hdr.sh_entsize
4165 = GOT_ENTRY_SIZE;
4167 /* Fill PLT and GOT entries for local STT_GNU_IFUNC symbols. */
4168 htab_traverse (htab->loc_hash_table,
4169 elf64_x86_64_finish_local_dynamic_symbol,
4170 info);
4172 return TRUE;
4175 /* Return address for Ith PLT stub in section PLT, for relocation REL
4176 or (bfd_vma) -1 if it should not be included. */
4178 static bfd_vma
4179 elf64_x86_64_plt_sym_val (bfd_vma i, const asection *plt,
4180 const arelent *rel ATTRIBUTE_UNUSED)
4182 return plt->vma + (i + 1) * PLT_ENTRY_SIZE;
4185 /* Handle an x86-64 specific section when reading an object file. This
4186 is called when elfcode.h finds a section with an unknown type. */
4188 static bfd_boolean
4189 elf64_x86_64_section_from_shdr (bfd *abfd,
4190 Elf_Internal_Shdr *hdr,
4191 const char *name,
4192 int shindex)
4194 if (hdr->sh_type != SHT_X86_64_UNWIND)
4195 return FALSE;
4197 if (! _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex))
4198 return FALSE;
4200 return TRUE;
4203 /* Hook called by the linker routine which adds symbols from an object
4204 file. We use it to put SHN_X86_64_LCOMMON items in .lbss, instead
4205 of .bss. */
4207 static bfd_boolean
4208 elf64_x86_64_add_symbol_hook (bfd *abfd,
4209 struct bfd_link_info *info,
4210 Elf_Internal_Sym *sym,
4211 const char **namep ATTRIBUTE_UNUSED,
4212 flagword *flagsp ATTRIBUTE_UNUSED,
4213 asection **secp,
4214 bfd_vma *valp)
4216 asection *lcomm;
4218 switch (sym->st_shndx)
4220 case SHN_X86_64_LCOMMON:
4221 lcomm = bfd_get_section_by_name (abfd, "LARGE_COMMON");
4222 if (lcomm == NULL)
4224 lcomm = bfd_make_section_with_flags (abfd,
4225 "LARGE_COMMON",
4226 (SEC_ALLOC
4227 | SEC_IS_COMMON
4228 | SEC_LINKER_CREATED));
4229 if (lcomm == NULL)
4230 return FALSE;
4231 elf_section_flags (lcomm) |= SHF_X86_64_LARGE;
4233 *secp = lcomm;
4234 *valp = sym->st_size;
4235 break;
4238 if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC)
4239 elf_tdata (info->output_bfd)->has_ifunc_symbols = TRUE;
4241 return TRUE;
4245 /* Given a BFD section, try to locate the corresponding ELF section
4246 index. */
4248 static bfd_boolean
4249 elf64_x86_64_elf_section_from_bfd_section (bfd *abfd ATTRIBUTE_UNUSED,
4250 asection *sec, int *index)
4252 if (sec == &_bfd_elf_large_com_section)
4254 *index = SHN_X86_64_LCOMMON;
4255 return TRUE;
4257 return FALSE;
4260 /* Process a symbol. */
4262 static void
4263 elf64_x86_64_symbol_processing (bfd *abfd ATTRIBUTE_UNUSED,
4264 asymbol *asym)
4266 elf_symbol_type *elfsym = (elf_symbol_type *) asym;
4268 switch (elfsym->internal_elf_sym.st_shndx)
4270 case SHN_X86_64_LCOMMON:
4271 asym->section = &_bfd_elf_large_com_section;
4272 asym->value = elfsym->internal_elf_sym.st_size;
4273 /* Common symbol doesn't set BSF_GLOBAL. */
4274 asym->flags &= ~BSF_GLOBAL;
4275 break;
4279 static bfd_boolean
4280 elf64_x86_64_common_definition (Elf_Internal_Sym *sym)
4282 return (sym->st_shndx == SHN_COMMON
4283 || sym->st_shndx == SHN_X86_64_LCOMMON);
4286 static unsigned int
4287 elf64_x86_64_common_section_index (asection *sec)
4289 if ((elf_section_flags (sec) & SHF_X86_64_LARGE) == 0)
4290 return SHN_COMMON;
4291 else
4292 return SHN_X86_64_LCOMMON;
4295 static asection *
4296 elf64_x86_64_common_section (asection *sec)
4298 if ((elf_section_flags (sec) & SHF_X86_64_LARGE) == 0)
4299 return bfd_com_section_ptr;
4300 else
4301 return &_bfd_elf_large_com_section;
4304 static bfd_boolean
4305 elf64_x86_64_merge_symbol (struct bfd_link_info *info ATTRIBUTE_UNUSED,
4306 struct elf_link_hash_entry **sym_hash ATTRIBUTE_UNUSED,
4307 struct elf_link_hash_entry *h,
4308 Elf_Internal_Sym *sym,
4309 asection **psec,
4310 bfd_vma *pvalue ATTRIBUTE_UNUSED,
4311 unsigned int *pold_alignment ATTRIBUTE_UNUSED,
4312 bfd_boolean *skip ATTRIBUTE_UNUSED,
4313 bfd_boolean *override ATTRIBUTE_UNUSED,
4314 bfd_boolean *type_change_ok ATTRIBUTE_UNUSED,
4315 bfd_boolean *size_change_ok ATTRIBUTE_UNUSED,
4316 bfd_boolean *newdef ATTRIBUTE_UNUSED,
4317 bfd_boolean *newdyn,
4318 bfd_boolean *newdyncommon ATTRIBUTE_UNUSED,
4319 bfd_boolean *newweak ATTRIBUTE_UNUSED,
4320 bfd *abfd ATTRIBUTE_UNUSED,
4321 asection **sec,
4322 bfd_boolean *olddef ATTRIBUTE_UNUSED,
4323 bfd_boolean *olddyn,
4324 bfd_boolean *olddyncommon ATTRIBUTE_UNUSED,
4325 bfd_boolean *oldweak ATTRIBUTE_UNUSED,
4326 bfd *oldbfd,
4327 asection **oldsec)
4329 /* A normal common symbol and a large common symbol result in a
4330 normal common symbol. We turn the large common symbol into a
4331 normal one. */
4332 if (!*olddyn
4333 && h->root.type == bfd_link_hash_common
4334 && !*newdyn
4335 && bfd_is_com_section (*sec)
4336 && *oldsec != *sec)
4338 if (sym->st_shndx == SHN_COMMON
4339 && (elf_section_flags (*oldsec) & SHF_X86_64_LARGE) != 0)
4341 h->root.u.c.p->section
4342 = bfd_make_section_old_way (oldbfd, "COMMON");
4343 h->root.u.c.p->section->flags = SEC_ALLOC;
4345 else if (sym->st_shndx == SHN_X86_64_LCOMMON
4346 && (elf_section_flags (*oldsec) & SHF_X86_64_LARGE) == 0)
4347 *psec = *sec = bfd_com_section_ptr;
4350 return TRUE;
4353 static int
4354 elf64_x86_64_additional_program_headers (bfd *abfd,
4355 struct bfd_link_info *info ATTRIBUTE_UNUSED)
4357 asection *s;
4358 int count = 0;
4360 /* Check to see if we need a large readonly segment. */
4361 s = bfd_get_section_by_name (abfd, ".lrodata");
4362 if (s && (s->flags & SEC_LOAD))
4363 count++;
4365 /* Check to see if we need a large data segment. Since .lbss sections
4366 is placed right after the .bss section, there should be no need for
4367 a large data segment just because of .lbss. */
4368 s = bfd_get_section_by_name (abfd, ".ldata");
4369 if (s && (s->flags & SEC_LOAD))
4370 count++;
4372 return count;
4375 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
4377 static bfd_boolean
4378 elf64_x86_64_hash_symbol (struct elf_link_hash_entry *h)
4380 if (h->plt.offset != (bfd_vma) -1
4381 && !h->def_regular
4382 && !h->pointer_equality_needed)
4383 return FALSE;
4385 return _bfd_elf_hash_symbol (h);
4388 static const struct bfd_elf_special_section
4389 elf64_x86_64_special_sections[]=
4391 { STRING_COMMA_LEN (".gnu.linkonce.lb"), -2, SHT_NOBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE},
4392 { STRING_COMMA_LEN (".gnu.linkonce.lr"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_X86_64_LARGE},
4393 { STRING_COMMA_LEN (".gnu.linkonce.lt"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_EXECINSTR + SHF_X86_64_LARGE},
4394 { STRING_COMMA_LEN (".lbss"), -2, SHT_NOBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE},
4395 { STRING_COMMA_LEN (".ldata"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE},
4396 { STRING_COMMA_LEN (".lrodata"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_X86_64_LARGE},
4397 { NULL, 0, 0, 0, 0 }
4400 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec
4401 #define TARGET_LITTLE_NAME "elf64-x86-64"
4402 #define ELF_ARCH bfd_arch_i386
4403 #define ELF_MACHINE_CODE EM_X86_64
4404 #define ELF_MAXPAGESIZE 0x200000
4405 #define ELF_MINPAGESIZE 0x1000
4406 #define ELF_COMMONPAGESIZE 0x1000
4408 #define elf_backend_can_gc_sections 1
4409 #define elf_backend_can_refcount 1
4410 #define elf_backend_want_got_plt 1
4411 #define elf_backend_plt_readonly 1
4412 #define elf_backend_want_plt_sym 0
4413 #define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
4414 #define elf_backend_rela_normal 1
4416 #define elf_info_to_howto elf64_x86_64_info_to_howto
4418 #define bfd_elf64_bfd_link_hash_table_create \
4419 elf64_x86_64_link_hash_table_create
4420 #define bfd_elf64_bfd_link_hash_table_free \
4421 elf64_x86_64_link_hash_table_free
4422 #define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup
4423 #define bfd_elf64_bfd_reloc_name_lookup \
4424 elf64_x86_64_reloc_name_lookup
4426 #define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol
4427 #define elf_backend_relocs_compatible _bfd_elf_relocs_compatible
4428 #define elf_backend_check_relocs elf64_x86_64_check_relocs
4429 #define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol
4430 #define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections
4431 #define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections
4432 #define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol
4433 #define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook
4434 #define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook
4435 #define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus
4436 #define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo
4437 #define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class
4438 #define elf_backend_relocate_section elf64_x86_64_relocate_section
4439 #define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections
4440 #define elf_backend_always_size_sections elf64_x86_64_always_size_sections
4441 #define elf_backend_init_index_section _bfd_elf_init_1_index_section
4442 #define elf_backend_plt_sym_val elf64_x86_64_plt_sym_val
4443 #define elf_backend_object_p elf64_x86_64_elf_object_p
4444 #define bfd_elf64_mkobject elf64_x86_64_mkobject
4446 #define elf_backend_section_from_shdr \
4447 elf64_x86_64_section_from_shdr
4449 #define elf_backend_section_from_bfd_section \
4450 elf64_x86_64_elf_section_from_bfd_section
4451 #define elf_backend_add_symbol_hook \
4452 elf64_x86_64_add_symbol_hook
4453 #define elf_backend_symbol_processing \
4454 elf64_x86_64_symbol_processing
4455 #define elf_backend_common_section_index \
4456 elf64_x86_64_common_section_index
4457 #define elf_backend_common_section \
4458 elf64_x86_64_common_section
4459 #define elf_backend_common_definition \
4460 elf64_x86_64_common_definition
4461 #define elf_backend_merge_symbol \
4462 elf64_x86_64_merge_symbol
4463 #define elf_backend_special_sections \
4464 elf64_x86_64_special_sections
4465 #define elf_backend_additional_program_headers \
4466 elf64_x86_64_additional_program_headers
4467 #define elf_backend_hash_symbol \
4468 elf64_x86_64_hash_symbol
4470 #undef elf_backend_post_process_headers
4471 #define elf_backend_post_process_headers _bfd_elf_set_osabi
4473 #include "elf64-target.h"
4475 /* FreeBSD support. */
4477 #undef TARGET_LITTLE_SYM
4478 #define TARGET_LITTLE_SYM bfd_elf64_x86_64_freebsd_vec
4479 #undef TARGET_LITTLE_NAME
4480 #define TARGET_LITTLE_NAME "elf64-x86-64-freebsd"
4482 #undef ELF_OSABI
4483 #define ELF_OSABI ELFOSABI_FREEBSD
4485 #undef elf64_bed
4486 #define elf64_bed elf64_x86_64_fbsd_bed
4488 #include "elf64-target.h"
4490 /* Intel L1OM support. */
4492 static bfd_boolean
4493 elf64_l1om_elf_object_p (bfd *abfd)
4495 /* Set the right machine number for an L1OM elf64 file. */
4496 bfd_default_set_arch_mach (abfd, bfd_arch_l1om, bfd_mach_l1om);
4497 return TRUE;
4500 #undef TARGET_LITTLE_SYM
4501 #define TARGET_LITTLE_SYM bfd_elf64_l1om_vec
4502 #undef TARGET_LITTLE_NAME
4503 #define TARGET_LITTLE_NAME "elf64-l1om"
4504 #undef ELF_ARCH
4505 #define ELF_ARCH bfd_arch_l1om
4507 #undef ELF_MACHINE_CODE
4508 #define ELF_MACHINE_CODE EM_L1OM
4510 #undef ELF_OSABI
4512 #undef elf64_bed
4513 #define elf64_bed elf64_l1om_bed
4515 #undef elf_backend_object_p
4516 #define elf_backend_object_p elf64_l1om_elf_object_p
4518 #undef elf_backend_post_process_headers
4520 #include "elf64-target.h"
4522 /* FreeBSD L1OM support. */
4524 #undef TARGET_LITTLE_SYM
4525 #define TARGET_LITTLE_SYM bfd_elf64_l1om_freebsd_vec
4526 #undef TARGET_LITTLE_NAME
4527 #define TARGET_LITTLE_NAME "elf64-l1om-freebsd"
4529 #undef ELF_OSABI
4530 #define ELF_OSABI ELFOSABI_FREEBSD
4532 #undef elf64_bed
4533 #define elf64_bed elf64_l1om_fbsd_bed
4535 #undef elf_backend_post_process_headers
4536 #define elf_backend_post_process_headers _bfd_elf_set_osabi
4538 #include "elf64-target.h"