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[deliverable/binutils-gdb.git] / bfd / elf32-i386.c
1 /* Intel 80386/80486-specific support for 32-bit ELF
2 Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
3 2003, 2004, 2005 Free Software Foundation, Inc.
4
5 This file is part of BFD, the Binary File Descriptor library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
20
21 #include "bfd.h"
22 #include "sysdep.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #include "elf-bfd.h"
26 #include "elf-vxworks.h"
27
28 /* 386 uses REL relocations instead of RELA. */
29 #define USE_REL 1
30
31 #include "elf/i386.h"
32
33 static reloc_howto_type elf_howto_table[]=
34 {
35 HOWTO(R_386_NONE, 0, 0, 0, FALSE, 0, complain_overflow_bitfield,
36 bfd_elf_generic_reloc, "R_386_NONE",
37 TRUE, 0x00000000, 0x00000000, FALSE),
38 HOWTO(R_386_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
39 bfd_elf_generic_reloc, "R_386_32",
40 TRUE, 0xffffffff, 0xffffffff, FALSE),
41 HOWTO(R_386_PC32, 0, 2, 32, TRUE, 0, complain_overflow_bitfield,
42 bfd_elf_generic_reloc, "R_386_PC32",
43 TRUE, 0xffffffff, 0xffffffff, TRUE),
44 HOWTO(R_386_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
45 bfd_elf_generic_reloc, "R_386_GOT32",
46 TRUE, 0xffffffff, 0xffffffff, FALSE),
47 HOWTO(R_386_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_bitfield,
48 bfd_elf_generic_reloc, "R_386_PLT32",
49 TRUE, 0xffffffff, 0xffffffff, TRUE),
50 HOWTO(R_386_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
51 bfd_elf_generic_reloc, "R_386_COPY",
52 TRUE, 0xffffffff, 0xffffffff, FALSE),
53 HOWTO(R_386_GLOB_DAT, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
54 bfd_elf_generic_reloc, "R_386_GLOB_DAT",
55 TRUE, 0xffffffff, 0xffffffff, FALSE),
56 HOWTO(R_386_JUMP_SLOT, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
57 bfd_elf_generic_reloc, "R_386_JUMP_SLOT",
58 TRUE, 0xffffffff, 0xffffffff, FALSE),
59 HOWTO(R_386_RELATIVE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
60 bfd_elf_generic_reloc, "R_386_RELATIVE",
61 TRUE, 0xffffffff, 0xffffffff, FALSE),
62 HOWTO(R_386_GOTOFF, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
63 bfd_elf_generic_reloc, "R_386_GOTOFF",
64 TRUE, 0xffffffff, 0xffffffff, FALSE),
65 HOWTO(R_386_GOTPC, 0, 2, 32, TRUE, 0, complain_overflow_bitfield,
66 bfd_elf_generic_reloc, "R_386_GOTPC",
67 TRUE, 0xffffffff, 0xffffffff, TRUE),
68
69 /* We have a gap in the reloc numbers here.
70 R_386_standard counts the number up to this point, and
71 R_386_ext_offset is the value to subtract from a reloc type of
72 R_386_16 thru R_386_PC8 to form an index into this table. */
73 #define R_386_standard (R_386_GOTPC + 1)
74 #define R_386_ext_offset (R_386_TLS_TPOFF - R_386_standard)
75
76 /* These relocs are a GNU extension. */
77 HOWTO(R_386_TLS_TPOFF, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
78 bfd_elf_generic_reloc, "R_386_TLS_TPOFF",
79 TRUE, 0xffffffff, 0xffffffff, FALSE),
80 HOWTO(R_386_TLS_IE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
81 bfd_elf_generic_reloc, "R_386_TLS_IE",
82 TRUE, 0xffffffff, 0xffffffff, FALSE),
83 HOWTO(R_386_TLS_GOTIE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
84 bfd_elf_generic_reloc, "R_386_TLS_GOTIE",
85 TRUE, 0xffffffff, 0xffffffff, FALSE),
86 HOWTO(R_386_TLS_LE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
87 bfd_elf_generic_reloc, "R_386_TLS_LE",
88 TRUE, 0xffffffff, 0xffffffff, FALSE),
89 HOWTO(R_386_TLS_GD, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
90 bfd_elf_generic_reloc, "R_386_TLS_GD",
91 TRUE, 0xffffffff, 0xffffffff, FALSE),
92 HOWTO(R_386_TLS_LDM, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
93 bfd_elf_generic_reloc, "R_386_TLS_LDM",
94 TRUE, 0xffffffff, 0xffffffff, FALSE),
95 HOWTO(R_386_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
96 bfd_elf_generic_reloc, "R_386_16",
97 TRUE, 0xffff, 0xffff, FALSE),
98 HOWTO(R_386_PC16, 0, 1, 16, TRUE, 0, complain_overflow_bitfield,
99 bfd_elf_generic_reloc, "R_386_PC16",
100 TRUE, 0xffff, 0xffff, TRUE),
101 HOWTO(R_386_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,
102 bfd_elf_generic_reloc, "R_386_8",
103 TRUE, 0xff, 0xff, FALSE),
104 HOWTO(R_386_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed,
105 bfd_elf_generic_reloc, "R_386_PC8",
106 TRUE, 0xff, 0xff, TRUE),
107
108 #define R_386_ext (R_386_PC8 + 1 - R_386_ext_offset)
109 #define R_386_tls_offset (R_386_TLS_LDO_32 - R_386_ext)
110 /* These are common with Solaris TLS implementation. */
111 HOWTO(R_386_TLS_LDO_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
112 bfd_elf_generic_reloc, "R_386_TLS_LDO_32",
113 TRUE, 0xffffffff, 0xffffffff, FALSE),
114 HOWTO(R_386_TLS_IE_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
115 bfd_elf_generic_reloc, "R_386_TLS_IE_32",
116 TRUE, 0xffffffff, 0xffffffff, FALSE),
117 HOWTO(R_386_TLS_LE_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
118 bfd_elf_generic_reloc, "R_386_TLS_LE_32",
119 TRUE, 0xffffffff, 0xffffffff, FALSE),
120 HOWTO(R_386_TLS_DTPMOD32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
121 bfd_elf_generic_reloc, "R_386_TLS_DTPMOD32",
122 TRUE, 0xffffffff, 0xffffffff, FALSE),
123 HOWTO(R_386_TLS_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
124 bfd_elf_generic_reloc, "R_386_TLS_DTPOFF32",
125 TRUE, 0xffffffff, 0xffffffff, FALSE),
126 HOWTO(R_386_TLS_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
127 bfd_elf_generic_reloc, "R_386_TLS_TPOFF32",
128 TRUE, 0xffffffff, 0xffffffff, FALSE),
129
130 /* Another gap. */
131 #define R_386_tls (R_386_TLS_TPOFF32 + 1 - R_386_tls_offset)
132 #define R_386_vt_offset (R_386_GNU_VTINHERIT - R_386_tls)
133
134 /* GNU extension to record C++ vtable hierarchy. */
135 HOWTO (R_386_GNU_VTINHERIT, /* type */
136 0, /* rightshift */
137 2, /* size (0 = byte, 1 = short, 2 = long) */
138 0, /* bitsize */
139 FALSE, /* pc_relative */
140 0, /* bitpos */
141 complain_overflow_dont, /* complain_on_overflow */
142 NULL, /* special_function */
143 "R_386_GNU_VTINHERIT", /* name */
144 FALSE, /* partial_inplace */
145 0, /* src_mask */
146 0, /* dst_mask */
147 FALSE), /* pcrel_offset */
148
149 /* GNU extension to record C++ vtable member usage. */
150 HOWTO (R_386_GNU_VTENTRY, /* type */
151 0, /* rightshift */
152 2, /* size (0 = byte, 1 = short, 2 = long) */
153 0, /* bitsize */
154 FALSE, /* pc_relative */
155 0, /* bitpos */
156 complain_overflow_dont, /* complain_on_overflow */
157 _bfd_elf_rel_vtable_reloc_fn, /* special_function */
158 "R_386_GNU_VTENTRY", /* name */
159 FALSE, /* partial_inplace */
160 0, /* src_mask */
161 0, /* dst_mask */
162 FALSE) /* pcrel_offset */
163
164 #define R_386_vt (R_386_GNU_VTENTRY + 1 - R_386_vt_offset)
165
166 };
167
168 #ifdef DEBUG_GEN_RELOC
169 #define TRACE(str) \
170 fprintf (stderr, "i386 bfd reloc lookup %d (%s)\n", code, str)
171 #else
172 #define TRACE(str)
173 #endif
174
175 static reloc_howto_type *
176 elf_i386_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
177 bfd_reloc_code_real_type code)
178 {
179 switch (code)
180 {
181 case BFD_RELOC_NONE:
182 TRACE ("BFD_RELOC_NONE");
183 return &elf_howto_table[R_386_NONE];
184
185 case BFD_RELOC_32:
186 TRACE ("BFD_RELOC_32");
187 return &elf_howto_table[R_386_32];
188
189 case BFD_RELOC_CTOR:
190 TRACE ("BFD_RELOC_CTOR");
191 return &elf_howto_table[R_386_32];
192
193 case BFD_RELOC_32_PCREL:
194 TRACE ("BFD_RELOC_PC32");
195 return &elf_howto_table[R_386_PC32];
196
197 case BFD_RELOC_386_GOT32:
198 TRACE ("BFD_RELOC_386_GOT32");
199 return &elf_howto_table[R_386_GOT32];
200
201 case BFD_RELOC_386_PLT32:
202 TRACE ("BFD_RELOC_386_PLT32");
203 return &elf_howto_table[R_386_PLT32];
204
205 case BFD_RELOC_386_COPY:
206 TRACE ("BFD_RELOC_386_COPY");
207 return &elf_howto_table[R_386_COPY];
208
209 case BFD_RELOC_386_GLOB_DAT:
210 TRACE ("BFD_RELOC_386_GLOB_DAT");
211 return &elf_howto_table[R_386_GLOB_DAT];
212
213 case BFD_RELOC_386_JUMP_SLOT:
214 TRACE ("BFD_RELOC_386_JUMP_SLOT");
215 return &elf_howto_table[R_386_JUMP_SLOT];
216
217 case BFD_RELOC_386_RELATIVE:
218 TRACE ("BFD_RELOC_386_RELATIVE");
219 return &elf_howto_table[R_386_RELATIVE];
220
221 case BFD_RELOC_386_GOTOFF:
222 TRACE ("BFD_RELOC_386_GOTOFF");
223 return &elf_howto_table[R_386_GOTOFF];
224
225 case BFD_RELOC_386_GOTPC:
226 TRACE ("BFD_RELOC_386_GOTPC");
227 return &elf_howto_table[R_386_GOTPC];
228
229 /* These relocs are a GNU extension. */
230 case BFD_RELOC_386_TLS_TPOFF:
231 TRACE ("BFD_RELOC_386_TLS_TPOFF");
232 return &elf_howto_table[R_386_TLS_TPOFF - R_386_ext_offset];
233
234 case BFD_RELOC_386_TLS_IE:
235 TRACE ("BFD_RELOC_386_TLS_IE");
236 return &elf_howto_table[R_386_TLS_IE - R_386_ext_offset];
237
238 case BFD_RELOC_386_TLS_GOTIE:
239 TRACE ("BFD_RELOC_386_TLS_GOTIE");
240 return &elf_howto_table[R_386_TLS_GOTIE - R_386_ext_offset];
241
242 case BFD_RELOC_386_TLS_LE:
243 TRACE ("BFD_RELOC_386_TLS_LE");
244 return &elf_howto_table[R_386_TLS_LE - R_386_ext_offset];
245
246 case BFD_RELOC_386_TLS_GD:
247 TRACE ("BFD_RELOC_386_TLS_GD");
248 return &elf_howto_table[R_386_TLS_GD - R_386_ext_offset];
249
250 case BFD_RELOC_386_TLS_LDM:
251 TRACE ("BFD_RELOC_386_TLS_LDM");
252 return &elf_howto_table[R_386_TLS_LDM - R_386_ext_offset];
253
254 case BFD_RELOC_16:
255 TRACE ("BFD_RELOC_16");
256 return &elf_howto_table[R_386_16 - R_386_ext_offset];
257
258 case BFD_RELOC_16_PCREL:
259 TRACE ("BFD_RELOC_16_PCREL");
260 return &elf_howto_table[R_386_PC16 - R_386_ext_offset];
261
262 case BFD_RELOC_8:
263 TRACE ("BFD_RELOC_8");
264 return &elf_howto_table[R_386_8 - R_386_ext_offset];
265
266 case BFD_RELOC_8_PCREL:
267 TRACE ("BFD_RELOC_8_PCREL");
268 return &elf_howto_table[R_386_PC8 - R_386_ext_offset];
269
270 /* Common with Sun TLS implementation. */
271 case BFD_RELOC_386_TLS_LDO_32:
272 TRACE ("BFD_RELOC_386_TLS_LDO_32");
273 return &elf_howto_table[R_386_TLS_LDO_32 - R_386_tls_offset];
274
275 case BFD_RELOC_386_TLS_IE_32:
276 TRACE ("BFD_RELOC_386_TLS_IE_32");
277 return &elf_howto_table[R_386_TLS_IE_32 - R_386_tls_offset];
278
279 case BFD_RELOC_386_TLS_LE_32:
280 TRACE ("BFD_RELOC_386_TLS_LE_32");
281 return &elf_howto_table[R_386_TLS_LE_32 - R_386_tls_offset];
282
283 case BFD_RELOC_386_TLS_DTPMOD32:
284 TRACE ("BFD_RELOC_386_TLS_DTPMOD32");
285 return &elf_howto_table[R_386_TLS_DTPMOD32 - R_386_tls_offset];
286
287 case BFD_RELOC_386_TLS_DTPOFF32:
288 TRACE ("BFD_RELOC_386_TLS_DTPOFF32");
289 return &elf_howto_table[R_386_TLS_DTPOFF32 - R_386_tls_offset];
290
291 case BFD_RELOC_386_TLS_TPOFF32:
292 TRACE ("BFD_RELOC_386_TLS_TPOFF32");
293 return &elf_howto_table[R_386_TLS_TPOFF32 - R_386_tls_offset];
294
295 case BFD_RELOC_VTABLE_INHERIT:
296 TRACE ("BFD_RELOC_VTABLE_INHERIT");
297 return &elf_howto_table[R_386_GNU_VTINHERIT - R_386_vt_offset];
298
299 case BFD_RELOC_VTABLE_ENTRY:
300 TRACE ("BFD_RELOC_VTABLE_ENTRY");
301 return &elf_howto_table[R_386_GNU_VTENTRY - R_386_vt_offset];
302
303 default:
304 break;
305 }
306
307 TRACE ("Unknown");
308 return 0;
309 }
310
311 static void
312 elf_i386_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED,
313 arelent *cache_ptr,
314 Elf_Internal_Rela *dst)
315 {
316 unsigned int r_type = ELF32_R_TYPE (dst->r_info);
317 unsigned int indx;
318
319 if ((indx = r_type) >= R_386_standard
320 && ((indx = r_type - R_386_ext_offset) - R_386_standard
321 >= R_386_ext - R_386_standard)
322 && ((indx = r_type - R_386_tls_offset) - R_386_ext
323 >= R_386_tls - R_386_ext)
324 && ((indx = r_type - R_386_vt_offset) - R_386_tls
325 >= R_386_vt - R_386_tls))
326 {
327 (*_bfd_error_handler) (_("%B: invalid relocation type %d"),
328 abfd, (int) r_type);
329 indx = R_386_NONE;
330 }
331 cache_ptr->howto = &elf_howto_table[indx];
332 }
333
334 /* Return whether a symbol name implies a local label. The UnixWare
335 2.1 cc generates temporary symbols that start with .X, so we
336 recognize them here. FIXME: do other SVR4 compilers also use .X?.
337 If so, we should move the .X recognition into
338 _bfd_elf_is_local_label_name. */
339
340 static bfd_boolean
341 elf_i386_is_local_label_name (bfd *abfd, const char *name)
342 {
343 if (name[0] == '.' && name[1] == 'X')
344 return TRUE;
345
346 return _bfd_elf_is_local_label_name (abfd, name);
347 }
348 \f
349 /* Support for core dump NOTE sections. */
350
351 static bfd_boolean
352 elf_i386_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
353 {
354 int offset;
355 size_t size;
356
357 if (note->namesz == 8 && strcmp (note->namedata, "FreeBSD") == 0)
358 {
359 int pr_version = bfd_get_32 (abfd, note->descdata);
360
361 if (pr_version != 1)
362 return FALSE;
363
364 /* pr_cursig */
365 elf_tdata (abfd)->core_signal = bfd_get_32 (abfd, note->descdata + 20);
366
367 /* pr_pid */
368 elf_tdata (abfd)->core_pid = bfd_get_32 (abfd, note->descdata + 24);
369
370 /* pr_reg */
371 offset = 28;
372 size = bfd_get_32 (abfd, note->descdata + 8);
373 }
374 else
375 {
376 switch (note->descsz)
377 {
378 default:
379 return FALSE;
380
381 case 144: /* Linux/i386 */
382 /* pr_cursig */
383 elf_tdata (abfd)->core_signal = bfd_get_16 (abfd, note->descdata + 12);
384
385 /* pr_pid */
386 elf_tdata (abfd)->core_pid = bfd_get_32 (abfd, note->descdata + 24);
387
388 /* pr_reg */
389 offset = 72;
390 size = 68;
391
392 break;
393 }
394 }
395
396 /* Make a ".reg/999" section. */
397 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
398 size, note->descpos + offset);
399 }
400
401 static bfd_boolean
402 elf_i386_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
403 {
404 if (note->namesz == 8 && strcmp (note->namedata, "FreeBSD") == 0)
405 {
406 int pr_version = bfd_get_32 (abfd, note->descdata);
407
408 if (pr_version != 1)
409 return FALSE;
410
411 elf_tdata (abfd)->core_program
412 = _bfd_elfcore_strndup (abfd, note->descdata + 8, 17);
413 elf_tdata (abfd)->core_command
414 = _bfd_elfcore_strndup (abfd, note->descdata + 25, 81);
415 }
416 else
417 {
418 switch (note->descsz)
419 {
420 default:
421 return FALSE;
422
423 case 124: /* Linux/i386 elf_prpsinfo. */
424 elf_tdata (abfd)->core_program
425 = _bfd_elfcore_strndup (abfd, note->descdata + 28, 16);
426 elf_tdata (abfd)->core_command
427 = _bfd_elfcore_strndup (abfd, note->descdata + 44, 80);
428 }
429 }
430
431 /* Note that for some reason, a spurious space is tacked
432 onto the end of the args in some (at least one anyway)
433 implementations, so strip it off if it exists. */
434 {
435 char *command = elf_tdata (abfd)->core_command;
436 int n = strlen (command);
437
438 if (0 < n && command[n - 1] == ' ')
439 command[n - 1] = '\0';
440 }
441
442 return TRUE;
443 }
444 \f
445 /* Functions for the i386 ELF linker.
446
447 In order to gain some understanding of code in this file without
448 knowing all the intricate details of the linker, note the
449 following:
450
451 Functions named elf_i386_* are called by external routines, other
452 functions are only called locally. elf_i386_* functions appear
453 in this file more or less in the order in which they are called
454 from external routines. eg. elf_i386_check_relocs is called
455 early in the link process, elf_i386_finish_dynamic_sections is
456 one of the last functions. */
457
458
459 /* The name of the dynamic interpreter. This is put in the .interp
460 section. */
461
462 #define ELF_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1"
463
464 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
465 copying dynamic variables from a shared lib into an app's dynbss
466 section, and instead use a dynamic relocation to point into the
467 shared lib. */
468 #define ELIMINATE_COPY_RELOCS 1
469
470 /* The size in bytes of an entry in the procedure linkage table. */
471
472 #define PLT_ENTRY_SIZE 16
473
474 /* The first entry in an absolute procedure linkage table looks like
475 this. See the SVR4 ABI i386 supplement to see how this works.
476 Will be padded to PLT_ENTRY_SIZE with htab->plt0_pad_byte. */
477
478 static const bfd_byte elf_i386_plt0_entry[12] =
479 {
480 0xff, 0x35, /* pushl contents of address */
481 0, 0, 0, 0, /* replaced with address of .got + 4. */
482 0xff, 0x25, /* jmp indirect */
483 0, 0, 0, 0 /* replaced with address of .got + 8. */
484 };
485
486 /* Subsequent entries in an absolute procedure linkage table look like
487 this. */
488
489 static const bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] =
490 {
491 0xff, 0x25, /* jmp indirect */
492 0, 0, 0, 0, /* replaced with address of this symbol in .got. */
493 0x68, /* pushl immediate */
494 0, 0, 0, 0, /* replaced with offset into relocation table. */
495 0xe9, /* jmp relative */
496 0, 0, 0, 0 /* replaced with offset to start of .plt. */
497 };
498
499 /* The first entry in a PIC procedure linkage table look like this.
500 Will be padded to PLT_ENTRY_SIZE with htab->plt0_pad_byte. */
501
502 static const bfd_byte elf_i386_pic_plt0_entry[12] =
503 {
504 0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */
505 0xff, 0xa3, 8, 0, 0, 0 /* jmp *8(%ebx) */
506 };
507
508 /* Subsequent entries in a PIC procedure linkage table look like this. */
509
510 static const bfd_byte elf_i386_pic_plt_entry[PLT_ENTRY_SIZE] =
511 {
512 0xff, 0xa3, /* jmp *offset(%ebx) */
513 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */
514 0x68, /* pushl immediate */
515 0, 0, 0, 0, /* replaced with offset into relocation table. */
516 0xe9, /* jmp relative */
517 0, 0, 0, 0 /* replaced with offset to start of .plt. */
518 };
519
520 /* On VxWorks, the .rel.plt.unloaded section has absolute relocations
521 for the PLTResolve stub and then for each PLT entry. */
522 #define PLTRESOLVE_RELOCS_SHLIB 0
523 #define PLTRESOLVE_RELOCS 2
524 #define PLT_NON_JUMP_SLOT_RELOCS 2
525
526 /* The i386 linker needs to keep track of the number of relocs that it
527 decides to copy as dynamic relocs in check_relocs for each symbol.
528 This is so that it can later discard them if they are found to be
529 unnecessary. We store the information in a field extending the
530 regular ELF linker hash table. */
531
532 struct elf_i386_dyn_relocs
533 {
534 struct elf_i386_dyn_relocs *next;
535
536 /* The input section of the reloc. */
537 asection *sec;
538
539 /* Total number of relocs copied for the input section. */
540 bfd_size_type count;
541
542 /* Number of pc-relative relocs copied for the input section. */
543 bfd_size_type pc_count;
544 };
545
546 /* i386 ELF linker hash entry. */
547
548 struct elf_i386_link_hash_entry
549 {
550 struct elf_link_hash_entry elf;
551
552 /* Track dynamic relocs copied for this symbol. */
553 struct elf_i386_dyn_relocs *dyn_relocs;
554
555 #define GOT_UNKNOWN 0
556 #define GOT_NORMAL 1
557 #define GOT_TLS_GD 2
558 #define GOT_TLS_IE 4
559 #define GOT_TLS_IE_POS 5
560 #define GOT_TLS_IE_NEG 6
561 #define GOT_TLS_IE_BOTH 7
562 unsigned char tls_type;
563 };
564
565 #define elf_i386_hash_entry(ent) ((struct elf_i386_link_hash_entry *)(ent))
566
567 struct elf_i386_obj_tdata
568 {
569 struct elf_obj_tdata root;
570
571 /* tls_type for each local got entry. */
572 char *local_got_tls_type;
573 };
574
575 #define elf_i386_tdata(abfd) \
576 ((struct elf_i386_obj_tdata *) (abfd)->tdata.any)
577
578 #define elf_i386_local_got_tls_type(abfd) \
579 (elf_i386_tdata (abfd)->local_got_tls_type)
580
581 static bfd_boolean
582 elf_i386_mkobject (bfd *abfd)
583 {
584 bfd_size_type amt = sizeof (struct elf_i386_obj_tdata);
585 abfd->tdata.any = bfd_zalloc (abfd, amt);
586 if (abfd->tdata.any == NULL)
587 return FALSE;
588 return TRUE;
589 }
590
591 /* i386 ELF linker hash table. */
592
593 struct elf_i386_link_hash_table
594 {
595 struct elf_link_hash_table elf;
596
597 /* Short-cuts to get to dynamic linker sections. */
598 asection *sgot;
599 asection *sgotplt;
600 asection *srelgot;
601 asection *splt;
602 asection *srelplt;
603 asection *sdynbss;
604 asection *srelbss;
605
606 /* The (unloaded but important) .rel.plt.unloaded section on VxWorks. */
607 asection *srelplt2;
608
609 /* Short-cuts to frequently used symbols for VxWorks targets. */
610 struct elf_link_hash_entry *hgot, *hplt;
611
612 /* True if the target system is VxWorks. */
613 int is_vxworks;
614
615 /* Value used to fill the last word of the first plt entry. */
616 bfd_byte plt0_pad_byte;
617
618 union {
619 bfd_signed_vma refcount;
620 bfd_vma offset;
621 } tls_ldm_got;
622
623 /* Small local sym to section mapping cache. */
624 struct sym_sec_cache sym_sec;
625 };
626
627 /* Get the i386 ELF linker hash table from a link_info structure. */
628
629 #define elf_i386_hash_table(p) \
630 ((struct elf_i386_link_hash_table *) ((p)->hash))
631
632 /* Create an entry in an i386 ELF linker hash table. */
633
634 static struct bfd_hash_entry *
635 link_hash_newfunc (struct bfd_hash_entry *entry,
636 struct bfd_hash_table *table,
637 const char *string)
638 {
639 /* Allocate the structure if it has not already been allocated by a
640 subclass. */
641 if (entry == NULL)
642 {
643 entry = bfd_hash_allocate (table,
644 sizeof (struct elf_i386_link_hash_entry));
645 if (entry == NULL)
646 return entry;
647 }
648
649 /* Call the allocation method of the superclass. */
650 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
651 if (entry != NULL)
652 {
653 struct elf_i386_link_hash_entry *eh;
654
655 eh = (struct elf_i386_link_hash_entry *) entry;
656 eh->dyn_relocs = NULL;
657 eh->tls_type = GOT_UNKNOWN;
658 }
659
660 return entry;
661 }
662
663 /* Create an i386 ELF linker hash table. */
664
665 static struct bfd_link_hash_table *
666 elf_i386_link_hash_table_create (bfd *abfd)
667 {
668 struct elf_i386_link_hash_table *ret;
669 bfd_size_type amt = sizeof (struct elf_i386_link_hash_table);
670
671 ret = bfd_malloc (amt);
672 if (ret == NULL)
673 return NULL;
674
675 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc))
676 {
677 free (ret);
678 return NULL;
679 }
680
681 ret->sgot = NULL;
682 ret->sgotplt = NULL;
683 ret->srelgot = NULL;
684 ret->splt = NULL;
685 ret->srelplt = NULL;
686 ret->sdynbss = NULL;
687 ret->srelbss = NULL;
688 ret->tls_ldm_got.refcount = 0;
689 ret->sym_sec.abfd = NULL;
690 ret->is_vxworks = 0;
691 ret->srelplt2 = NULL;
692 ret->hgot = NULL;
693 ret->hplt = NULL;
694 ret->plt0_pad_byte = 0;
695
696 return &ret->elf.root;
697 }
698
699 /* Create .got, .gotplt, and .rel.got sections in DYNOBJ, and set up
700 shortcuts to them in our hash table. */
701
702 static bfd_boolean
703 create_got_section (bfd *dynobj, struct bfd_link_info *info)
704 {
705 struct elf_i386_link_hash_table *htab;
706
707 if (! _bfd_elf_create_got_section (dynobj, info))
708 return FALSE;
709
710 htab = elf_i386_hash_table (info);
711 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
712 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
713 if (!htab->sgot || !htab->sgotplt)
714 abort ();
715
716 htab->srelgot = bfd_make_section_with_flags (dynobj, ".rel.got",
717 (SEC_ALLOC | SEC_LOAD
718 | SEC_HAS_CONTENTS
719 | SEC_IN_MEMORY
720 | SEC_LINKER_CREATED
721 | SEC_READONLY));
722 if (htab->srelgot == NULL
723 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 2))
724 return FALSE;
725 return TRUE;
726 }
727
728 /* Create .plt, .rel.plt, .got, .got.plt, .rel.got, .dynbss, and
729 .rel.bss sections in DYNOBJ, and set up shortcuts to them in our
730 hash table. */
731
732 static bfd_boolean
733 elf_i386_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info)
734 {
735 struct elf_i386_link_hash_table *htab;
736 asection * s;
737 int flags;
738 const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
739
740 htab = elf_i386_hash_table (info);
741 if (!htab->sgot && !create_got_section (dynobj, info))
742 return FALSE;
743
744 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
745 return FALSE;
746
747 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
748 htab->srelplt = bfd_get_section_by_name (dynobj, ".rel.plt");
749 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
750 if (!info->shared)
751 htab->srelbss = bfd_get_section_by_name (dynobj, ".rel.bss");
752
753 if (!htab->splt || !htab->srelplt || !htab->sdynbss
754 || (!info->shared && !htab->srelbss))
755 abort ();
756
757 if (htab->is_vxworks && !info->shared)
758 {
759 s = bfd_make_section (dynobj, ".rel.plt.unloaded");
760 flags = (SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_READONLY
761 | SEC_LINKER_CREATED);
762 if (s == NULL
763 || ! bfd_set_section_flags (dynobj, s, flags)
764 || ! bfd_set_section_alignment (dynobj, s, bed->s->log_file_align))
765 return FALSE;
766 htab->srelplt2 = s;
767 }
768
769 return TRUE;
770 }
771
772 /* Copy the extra info we tack onto an elf_link_hash_entry. */
773
774 static void
775 elf_i386_copy_indirect_symbol (const struct elf_backend_data *bed,
776 struct elf_link_hash_entry *dir,
777 struct elf_link_hash_entry *ind)
778 {
779 struct elf_i386_link_hash_entry *edir, *eind;
780
781 edir = (struct elf_i386_link_hash_entry *) dir;
782 eind = (struct elf_i386_link_hash_entry *) ind;
783
784 if (eind->dyn_relocs != NULL)
785 {
786 if (edir->dyn_relocs != NULL)
787 {
788 struct elf_i386_dyn_relocs **pp;
789 struct elf_i386_dyn_relocs *p;
790
791 if (ind->root.type == bfd_link_hash_indirect)
792 abort ();
793
794 /* Add reloc counts against the weak sym to the strong sym
795 list. Merge any entries against the same section. */
796 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
797 {
798 struct elf_i386_dyn_relocs *q;
799
800 for (q = edir->dyn_relocs; q != NULL; q = q->next)
801 if (q->sec == p->sec)
802 {
803 q->pc_count += p->pc_count;
804 q->count += p->count;
805 *pp = p->next;
806 break;
807 }
808 if (q == NULL)
809 pp = &p->next;
810 }
811 *pp = edir->dyn_relocs;
812 }
813
814 edir->dyn_relocs = eind->dyn_relocs;
815 eind->dyn_relocs = NULL;
816 }
817
818 if (ind->root.type == bfd_link_hash_indirect
819 && dir->got.refcount <= 0)
820 {
821 edir->tls_type = eind->tls_type;
822 eind->tls_type = GOT_UNKNOWN;
823 }
824
825 if (ELIMINATE_COPY_RELOCS
826 && ind->root.type != bfd_link_hash_indirect
827 && dir->dynamic_adjusted)
828 {
829 /* If called to transfer flags for a weakdef during processing
830 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
831 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
832 dir->ref_dynamic |= ind->ref_dynamic;
833 dir->ref_regular |= ind->ref_regular;
834 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
835 dir->needs_plt |= ind->needs_plt;
836 dir->pointer_equality_needed |= ind->pointer_equality_needed;
837 }
838 else
839 _bfd_elf_link_hash_copy_indirect (bed, dir, ind);
840 }
841
842 static int
843 elf_i386_tls_transition (struct bfd_link_info *info, int r_type, int is_local)
844 {
845 if (info->shared)
846 return r_type;
847
848 switch (r_type)
849 {
850 case R_386_TLS_GD:
851 case R_386_TLS_IE_32:
852 if (is_local)
853 return R_386_TLS_LE_32;
854 return R_386_TLS_IE_32;
855 case R_386_TLS_IE:
856 case R_386_TLS_GOTIE:
857 if (is_local)
858 return R_386_TLS_LE_32;
859 return r_type;
860 case R_386_TLS_LDM:
861 return R_386_TLS_LE_32;
862 }
863
864 return r_type;
865 }
866
867 /* Look through the relocs for a section during the first phase, and
868 calculate needed space in the global offset table, procedure linkage
869 table, and dynamic reloc sections. */
870
871 static bfd_boolean
872 elf_i386_check_relocs (bfd *abfd,
873 struct bfd_link_info *info,
874 asection *sec,
875 const Elf_Internal_Rela *relocs)
876 {
877 struct elf_i386_link_hash_table *htab;
878 Elf_Internal_Shdr *symtab_hdr;
879 struct elf_link_hash_entry **sym_hashes;
880 const Elf_Internal_Rela *rel;
881 const Elf_Internal_Rela *rel_end;
882 asection *sreloc;
883
884 if (info->relocatable)
885 return TRUE;
886
887 htab = elf_i386_hash_table (info);
888 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
889 sym_hashes = elf_sym_hashes (abfd);
890
891 sreloc = NULL;
892
893 rel_end = relocs + sec->reloc_count;
894 for (rel = relocs; rel < rel_end; rel++)
895 {
896 unsigned int r_type;
897 unsigned long r_symndx;
898 struct elf_link_hash_entry *h;
899
900 r_symndx = ELF32_R_SYM (rel->r_info);
901 r_type = ELF32_R_TYPE (rel->r_info);
902
903 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
904 {
905 (*_bfd_error_handler) (_("%B: bad symbol index: %d"),
906 abfd,
907 r_symndx);
908 return FALSE;
909 }
910
911 if (r_symndx < symtab_hdr->sh_info)
912 h = NULL;
913 else
914 {
915 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
916 while (h->root.type == bfd_link_hash_indirect
917 || h->root.type == bfd_link_hash_warning)
918 h = (struct elf_link_hash_entry *) h->root.u.i.link;
919 }
920
921 r_type = elf_i386_tls_transition (info, r_type, h == NULL);
922
923 switch (r_type)
924 {
925 case R_386_TLS_LDM:
926 htab->tls_ldm_got.refcount += 1;
927 goto create_got;
928
929 case R_386_PLT32:
930 /* This symbol requires a procedure linkage table entry. We
931 actually build the entry in adjust_dynamic_symbol,
932 because this might be a case of linking PIC code which is
933 never referenced by a dynamic object, in which case we
934 don't need to generate a procedure linkage table entry
935 after all. */
936
937 /* If this is a local symbol, we resolve it directly without
938 creating a procedure linkage table entry. */
939 if (h == NULL)
940 continue;
941
942 h->needs_plt = 1;
943 h->plt.refcount += 1;
944 break;
945
946 case R_386_TLS_IE_32:
947 case R_386_TLS_IE:
948 case R_386_TLS_GOTIE:
949 if (info->shared)
950 info->flags |= DF_STATIC_TLS;
951 /* Fall through */
952
953 case R_386_GOT32:
954 case R_386_TLS_GD:
955 /* This symbol requires a global offset table entry. */
956 {
957 int tls_type, old_tls_type;
958
959 switch (r_type)
960 {
961 default:
962 case R_386_GOT32: tls_type = GOT_NORMAL; break;
963 case R_386_TLS_GD: tls_type = GOT_TLS_GD; break;
964 case R_386_TLS_IE_32:
965 if (ELF32_R_TYPE (rel->r_info) == r_type)
966 tls_type = GOT_TLS_IE_NEG;
967 else
968 /* If this is a GD->IE transition, we may use either of
969 R_386_TLS_TPOFF and R_386_TLS_TPOFF32. */
970 tls_type = GOT_TLS_IE;
971 break;
972 case R_386_TLS_IE:
973 case R_386_TLS_GOTIE:
974 tls_type = GOT_TLS_IE_POS; break;
975 }
976
977 if (h != NULL)
978 {
979 h->got.refcount += 1;
980 old_tls_type = elf_i386_hash_entry(h)->tls_type;
981 }
982 else
983 {
984 bfd_signed_vma *local_got_refcounts;
985
986 /* This is a global offset table entry for a local symbol. */
987 local_got_refcounts = elf_local_got_refcounts (abfd);
988 if (local_got_refcounts == NULL)
989 {
990 bfd_size_type size;
991
992 size = symtab_hdr->sh_info;
993 size *= (sizeof (bfd_signed_vma) + sizeof(char));
994 local_got_refcounts = bfd_zalloc (abfd, size);
995 if (local_got_refcounts == NULL)
996 return FALSE;
997 elf_local_got_refcounts (abfd) = local_got_refcounts;
998 elf_i386_local_got_tls_type (abfd)
999 = (char *) (local_got_refcounts + symtab_hdr->sh_info);
1000 }
1001 local_got_refcounts[r_symndx] += 1;
1002 old_tls_type = elf_i386_local_got_tls_type (abfd) [r_symndx];
1003 }
1004
1005 if ((old_tls_type & GOT_TLS_IE) && (tls_type & GOT_TLS_IE))
1006 tls_type |= old_tls_type;
1007 /* If a TLS symbol is accessed using IE at least once,
1008 there is no point to use dynamic model for it. */
1009 else if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
1010 && (old_tls_type != GOT_TLS_GD
1011 || (tls_type & GOT_TLS_IE) == 0))
1012 {
1013 if ((old_tls_type & GOT_TLS_IE) && tls_type == GOT_TLS_GD)
1014 tls_type = old_tls_type;
1015 else
1016 {
1017 (*_bfd_error_handler)
1018 (_("%B: `%s' accessed both as normal and "
1019 "thread local symbol"),
1020 abfd,
1021 h ? h->root.root.string : "<local>");
1022 return FALSE;
1023 }
1024 }
1025
1026 if (old_tls_type != tls_type)
1027 {
1028 if (h != NULL)
1029 elf_i386_hash_entry (h)->tls_type = tls_type;
1030 else
1031 elf_i386_local_got_tls_type (abfd) [r_symndx] = tls_type;
1032 }
1033 }
1034 /* Fall through */
1035
1036 case R_386_GOTOFF:
1037 case R_386_GOTPC:
1038 create_got:
1039 if (htab->sgot == NULL)
1040 {
1041 if (htab->elf.dynobj == NULL)
1042 htab->elf.dynobj = abfd;
1043 if (!create_got_section (htab->elf.dynobj, info))
1044 return FALSE;
1045 }
1046 if (r_type != R_386_TLS_IE)
1047 break;
1048 /* Fall through */
1049
1050 case R_386_TLS_LE_32:
1051 case R_386_TLS_LE:
1052 if (!info->shared)
1053 break;
1054 info->flags |= DF_STATIC_TLS;
1055 /* Fall through */
1056
1057 case R_386_32:
1058 case R_386_PC32:
1059 if (h != NULL && !info->shared)
1060 {
1061 /* If this reloc is in a read-only section, we might
1062 need a copy reloc. We can't check reliably at this
1063 stage whether the section is read-only, as input
1064 sections have not yet been mapped to output sections.
1065 Tentatively set the flag for now, and correct in
1066 adjust_dynamic_symbol. */
1067 h->non_got_ref = 1;
1068
1069 /* We may need a .plt entry if the function this reloc
1070 refers to is in a shared lib. */
1071 h->plt.refcount += 1;
1072 if (r_type != R_386_PC32)
1073 h->pointer_equality_needed = 1;
1074 }
1075
1076 /* If we are creating a shared library, and this is a reloc
1077 against a global symbol, or a non PC relative reloc
1078 against a local symbol, then we need to copy the reloc
1079 into the shared library. However, if we are linking with
1080 -Bsymbolic, we do not need to copy a reloc against a
1081 global symbol which is defined in an object we are
1082 including in the link (i.e., DEF_REGULAR is set). At
1083 this point we have not seen all the input files, so it is
1084 possible that DEF_REGULAR is not set now but will be set
1085 later (it is never cleared). In case of a weak definition,
1086 DEF_REGULAR may be cleared later by a strong definition in
1087 a shared library. We account for that possibility below by
1088 storing information in the relocs_copied field of the hash
1089 table entry. A similar situation occurs when creating
1090 shared libraries and symbol visibility changes render the
1091 symbol local.
1092
1093 If on the other hand, we are creating an executable, we
1094 may need to keep relocations for symbols satisfied by a
1095 dynamic library if we manage to avoid copy relocs for the
1096 symbol. */
1097 if ((info->shared
1098 && (sec->flags & SEC_ALLOC) != 0
1099 && (r_type != R_386_PC32
1100 || (h != NULL
1101 && (! info->symbolic
1102 || h->root.type == bfd_link_hash_defweak
1103 || !h->def_regular))))
1104 || (ELIMINATE_COPY_RELOCS
1105 && !info->shared
1106 && (sec->flags & SEC_ALLOC) != 0
1107 && h != NULL
1108 && (h->root.type == bfd_link_hash_defweak
1109 || !h->def_regular)))
1110 {
1111 struct elf_i386_dyn_relocs *p;
1112 struct elf_i386_dyn_relocs **head;
1113
1114 /* We must copy these reloc types into the output file.
1115 Create a reloc section in dynobj and make room for
1116 this reloc. */
1117 if (sreloc == NULL)
1118 {
1119 const char *name;
1120 bfd *dynobj;
1121 unsigned int strndx = elf_elfheader (abfd)->e_shstrndx;
1122 unsigned int shnam = elf_section_data (sec)->rel_hdr.sh_name;
1123
1124 name = bfd_elf_string_from_elf_section (abfd, strndx, shnam);
1125 if (name == NULL)
1126 return FALSE;
1127
1128 if (strncmp (name, ".rel", 4) != 0
1129 || strcmp (bfd_get_section_name (abfd, sec),
1130 name + 4) != 0)
1131 {
1132 (*_bfd_error_handler)
1133 (_("%B: bad relocation section name `%s\'"),
1134 abfd, name);
1135 }
1136
1137 if (htab->elf.dynobj == NULL)
1138 htab->elf.dynobj = abfd;
1139
1140 dynobj = htab->elf.dynobj;
1141 sreloc = bfd_get_section_by_name (dynobj, name);
1142 if (sreloc == NULL)
1143 {
1144 flagword flags;
1145
1146 flags = (SEC_HAS_CONTENTS | SEC_READONLY
1147 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
1148 if ((sec->flags & SEC_ALLOC) != 0)
1149 flags |= SEC_ALLOC | SEC_LOAD;
1150 sreloc = bfd_make_section_with_flags (dynobj,
1151 name,
1152 flags);
1153 if (sreloc == NULL
1154 || ! bfd_set_section_alignment (dynobj, sreloc, 2))
1155 return FALSE;
1156 }
1157 elf_section_data (sec)->sreloc = sreloc;
1158 }
1159
1160 /* If this is a global symbol, we count the number of
1161 relocations we need for this symbol. */
1162 if (h != NULL)
1163 {
1164 head = &((struct elf_i386_link_hash_entry *) h)->dyn_relocs;
1165 }
1166 else
1167 {
1168 /* Track dynamic relocs needed for local syms too.
1169 We really need local syms available to do this
1170 easily. Oh well. */
1171
1172 asection *s;
1173 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
1174 sec, r_symndx);
1175 if (s == NULL)
1176 return FALSE;
1177
1178 head = ((struct elf_i386_dyn_relocs **)
1179 &elf_section_data (s)->local_dynrel);
1180 }
1181
1182 p = *head;
1183 if (p == NULL || p->sec != sec)
1184 {
1185 bfd_size_type amt = sizeof *p;
1186 p = bfd_alloc (htab->elf.dynobj, amt);
1187 if (p == NULL)
1188 return FALSE;
1189 p->next = *head;
1190 *head = p;
1191 p->sec = sec;
1192 p->count = 0;
1193 p->pc_count = 0;
1194 }
1195
1196 p->count += 1;
1197 if (r_type == R_386_PC32)
1198 p->pc_count += 1;
1199 }
1200 break;
1201
1202 /* This relocation describes the C++ object vtable hierarchy.
1203 Reconstruct it for later use during GC. */
1204 case R_386_GNU_VTINHERIT:
1205 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
1206 return FALSE;
1207 break;
1208
1209 /* This relocation describes which C++ vtable entries are actually
1210 used. Record for later use during GC. */
1211 case R_386_GNU_VTENTRY:
1212 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset))
1213 return FALSE;
1214 break;
1215
1216 default:
1217 break;
1218 }
1219 }
1220
1221 return TRUE;
1222 }
1223
1224 /* Return the section that should be marked against GC for a given
1225 relocation. */
1226
1227 static asection *
1228 elf_i386_gc_mark_hook (asection *sec,
1229 struct bfd_link_info *info ATTRIBUTE_UNUSED,
1230 Elf_Internal_Rela *rel,
1231 struct elf_link_hash_entry *h,
1232 Elf_Internal_Sym *sym)
1233 {
1234 if (h != NULL)
1235 {
1236 switch (ELF32_R_TYPE (rel->r_info))
1237 {
1238 case R_386_GNU_VTINHERIT:
1239 case R_386_GNU_VTENTRY:
1240 break;
1241
1242 default:
1243 switch (h->root.type)
1244 {
1245 case bfd_link_hash_defined:
1246 case bfd_link_hash_defweak:
1247 return h->root.u.def.section;
1248
1249 case bfd_link_hash_common:
1250 return h->root.u.c.p->section;
1251
1252 default:
1253 break;
1254 }
1255 }
1256 }
1257 else
1258 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
1259
1260 return NULL;
1261 }
1262
1263 /* Update the got entry reference counts for the section being removed. */
1264
1265 static bfd_boolean
1266 elf_i386_gc_sweep_hook (bfd *abfd,
1267 struct bfd_link_info *info,
1268 asection *sec,
1269 const Elf_Internal_Rela *relocs)
1270 {
1271 Elf_Internal_Shdr *symtab_hdr;
1272 struct elf_link_hash_entry **sym_hashes;
1273 bfd_signed_vma *local_got_refcounts;
1274 const Elf_Internal_Rela *rel, *relend;
1275
1276 elf_section_data (sec)->local_dynrel = NULL;
1277
1278 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1279 sym_hashes = elf_sym_hashes (abfd);
1280 local_got_refcounts = elf_local_got_refcounts (abfd);
1281
1282 relend = relocs + sec->reloc_count;
1283 for (rel = relocs; rel < relend; rel++)
1284 {
1285 unsigned long r_symndx;
1286 unsigned int r_type;
1287 struct elf_link_hash_entry *h = NULL;
1288
1289 r_symndx = ELF32_R_SYM (rel->r_info);
1290 if (r_symndx >= symtab_hdr->sh_info)
1291 {
1292 struct elf_i386_link_hash_entry *eh;
1293 struct elf_i386_dyn_relocs **pp;
1294 struct elf_i386_dyn_relocs *p;
1295
1296 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1297 while (h->root.type == bfd_link_hash_indirect
1298 || h->root.type == bfd_link_hash_warning)
1299 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1300 eh = (struct elf_i386_link_hash_entry *) h;
1301
1302 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1303 if (p->sec == sec)
1304 {
1305 /* Everything must go for SEC. */
1306 *pp = p->next;
1307 break;
1308 }
1309 }
1310
1311 r_type = ELF32_R_TYPE (rel->r_info);
1312 r_type = elf_i386_tls_transition (info, r_type, h != NULL);
1313 switch (r_type)
1314 {
1315 case R_386_TLS_LDM:
1316 if (elf_i386_hash_table (info)->tls_ldm_got.refcount > 0)
1317 elf_i386_hash_table (info)->tls_ldm_got.refcount -= 1;
1318 break;
1319
1320 case R_386_TLS_GD:
1321 case R_386_TLS_IE_32:
1322 case R_386_TLS_IE:
1323 case R_386_TLS_GOTIE:
1324 case R_386_GOT32:
1325 if (h != NULL)
1326 {
1327 if (h->got.refcount > 0)
1328 h->got.refcount -= 1;
1329 }
1330 else if (local_got_refcounts != NULL)
1331 {
1332 if (local_got_refcounts[r_symndx] > 0)
1333 local_got_refcounts[r_symndx] -= 1;
1334 }
1335 break;
1336
1337 case R_386_32:
1338 case R_386_PC32:
1339 if (info->shared)
1340 break;
1341 /* Fall through */
1342
1343 case R_386_PLT32:
1344 if (h != NULL)
1345 {
1346 if (h->plt.refcount > 0)
1347 h->plt.refcount -= 1;
1348 }
1349 break;
1350
1351 default:
1352 break;
1353 }
1354 }
1355
1356 return TRUE;
1357 }
1358
1359 /* Adjust a symbol defined by a dynamic object and referenced by a
1360 regular object. The current definition is in some section of the
1361 dynamic object, but we're not including those sections. We have to
1362 change the definition to something the rest of the link can
1363 understand. */
1364
1365 static bfd_boolean
1366 elf_i386_adjust_dynamic_symbol (struct bfd_link_info *info,
1367 struct elf_link_hash_entry *h)
1368 {
1369 struct elf_i386_link_hash_table *htab;
1370 asection *s;
1371 unsigned int power_of_two;
1372
1373 /* If this is a function, put it in the procedure linkage table. We
1374 will fill in the contents of the procedure linkage table later,
1375 when we know the address of the .got section. */
1376 if (h->type == STT_FUNC
1377 || h->needs_plt)
1378 {
1379 if (h->plt.refcount <= 0
1380 || SYMBOL_CALLS_LOCAL (info, h)
1381 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1382 && h->root.type == bfd_link_hash_undefweak))
1383 {
1384 /* This case can occur if we saw a PLT32 reloc in an input
1385 file, but the symbol was never referred to by a dynamic
1386 object, or if all references were garbage collected. In
1387 such a case, we don't actually need to build a procedure
1388 linkage table, and we can just do a PC32 reloc instead. */
1389 h->plt.offset = (bfd_vma) -1;
1390 h->needs_plt = 0;
1391 }
1392
1393 return TRUE;
1394 }
1395 else
1396 /* It's possible that we incorrectly decided a .plt reloc was
1397 needed for an R_386_PC32 reloc to a non-function sym in
1398 check_relocs. We can't decide accurately between function and
1399 non-function syms in check-relocs; Objects loaded later in
1400 the link may change h->type. So fix it now. */
1401 h->plt.offset = (bfd_vma) -1;
1402
1403 /* If this is a weak symbol, and there is a real definition, the
1404 processor independent code will have arranged for us to see the
1405 real definition first, and we can just use the same value. */
1406 if (h->u.weakdef != NULL)
1407 {
1408 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1409 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1410 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1411 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1412 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1413 h->non_got_ref = h->u.weakdef->non_got_ref;
1414 return TRUE;
1415 }
1416
1417 /* This is a reference to a symbol defined by a dynamic object which
1418 is not a function. */
1419
1420 /* If we are creating a shared library, we must presume that the
1421 only references to the symbol are via the global offset table.
1422 For such cases we need not do anything here; the relocations will
1423 be handled correctly by relocate_section. */
1424 if (info->shared)
1425 return TRUE;
1426
1427 /* If there are no references to this symbol that do not use the
1428 GOT, we don't need to generate a copy reloc. */
1429 if (!h->non_got_ref)
1430 return TRUE;
1431
1432 /* If -z nocopyreloc was given, we won't generate them either. */
1433 if (info->nocopyreloc)
1434 {
1435 h->non_got_ref = 0;
1436 return TRUE;
1437 }
1438
1439 htab = elf_i386_hash_table (info);
1440
1441 /* If there aren't any dynamic relocs in read-only sections, then
1442 we can keep the dynamic relocs and avoid the copy reloc. This
1443 doesn't work on VxWorks, where we can not have dynamic relocations
1444 (other than copy and jump slot relocations) in an executable. */
1445 if (ELIMINATE_COPY_RELOCS && !htab->is_vxworks)
1446 {
1447 struct elf_i386_link_hash_entry * eh;
1448 struct elf_i386_dyn_relocs *p;
1449
1450 eh = (struct elf_i386_link_hash_entry *) h;
1451 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1452 {
1453 s = p->sec->output_section;
1454 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1455 break;
1456 }
1457
1458 if (p == NULL)
1459 {
1460 h->non_got_ref = 0;
1461 return TRUE;
1462 }
1463 }
1464
1465 /* We must allocate the symbol in our .dynbss section, which will
1466 become part of the .bss section of the executable. There will be
1467 an entry for this symbol in the .dynsym section. The dynamic
1468 object will contain position independent code, so all references
1469 from the dynamic object to this symbol will go through the global
1470 offset table. The dynamic linker will use the .dynsym entry to
1471 determine the address it must put in the global offset table, so
1472 both the dynamic object and the regular object will refer to the
1473 same memory location for the variable. */
1474
1475 /* We must generate a R_386_COPY reloc to tell the dynamic linker to
1476 copy the initial value out of the dynamic object and into the
1477 runtime process image. */
1478 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1479 {
1480 htab->srelbss->size += sizeof (Elf32_External_Rel);
1481 h->needs_copy = 1;
1482 }
1483
1484 /* We need to figure out the alignment required for this symbol. I
1485 have no idea how ELF linkers handle this. */
1486 power_of_two = bfd_log2 (h->size);
1487 if (power_of_two > 3)
1488 power_of_two = 3;
1489
1490 /* Apply the required alignment. */
1491 s = htab->sdynbss;
1492 s->size = BFD_ALIGN (s->size, (bfd_size_type) (1 << power_of_two));
1493 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1494 {
1495 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1496 return FALSE;
1497 }
1498
1499 /* Define the symbol as being at this point in the section. */
1500 h->root.u.def.section = s;
1501 h->root.u.def.value = s->size;
1502
1503 /* Increment the section size to make room for the symbol. */
1504 s->size += h->size;
1505
1506 return TRUE;
1507 }
1508
1509 /* Allocate space in .plt, .got and associated reloc sections for
1510 dynamic relocs. */
1511
1512 static bfd_boolean
1513 allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
1514 {
1515 struct bfd_link_info *info;
1516 struct elf_i386_link_hash_table *htab;
1517 struct elf_i386_link_hash_entry *eh;
1518 struct elf_i386_dyn_relocs *p;
1519
1520 if (h->root.type == bfd_link_hash_indirect)
1521 return TRUE;
1522
1523 if (h->root.type == bfd_link_hash_warning)
1524 /* When warning symbols are created, they **replace** the "real"
1525 entry in the hash table, thus we never get to see the real
1526 symbol in a hash traversal. So look at it now. */
1527 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1528
1529 info = (struct bfd_link_info *) inf;
1530 htab = elf_i386_hash_table (info);
1531
1532 if (htab->elf.dynamic_sections_created
1533 && h->plt.refcount > 0)
1534 {
1535 /* Make sure this symbol is output as a dynamic symbol.
1536 Undefined weak syms won't yet be marked as dynamic. */
1537 if (h->dynindx == -1
1538 && !h->forced_local)
1539 {
1540 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1541 return FALSE;
1542 }
1543
1544 if (info->shared
1545 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
1546 {
1547 asection *s = htab->splt;
1548
1549 /* If this is the first .plt entry, make room for the special
1550 first entry. */
1551 if (s->size == 0)
1552 s->size += PLT_ENTRY_SIZE;
1553
1554 h->plt.offset = s->size;
1555
1556 /* If this symbol is not defined in a regular file, and we are
1557 not generating a shared library, then set the symbol to this
1558 location in the .plt. This is required to make function
1559 pointers compare as equal between the normal executable and
1560 the shared library. */
1561 if (! info->shared
1562 && !h->def_regular)
1563 {
1564 h->root.u.def.section = s;
1565 h->root.u.def.value = h->plt.offset;
1566 }
1567
1568 /* Make room for this entry. */
1569 s->size += PLT_ENTRY_SIZE;
1570
1571 /* We also need to make an entry in the .got.plt section, which
1572 will be placed in the .got section by the linker script. */
1573 htab->sgotplt->size += 4;
1574
1575 /* We also need to make an entry in the .rel.plt section. */
1576 htab->srelplt->size += sizeof (Elf32_External_Rel);
1577
1578 if (htab->is_vxworks && !info->shared)
1579 {
1580 /* VxWorks has a second set of relocations for each PLT entry
1581 in executables. They go in a separate relocation section,
1582 which is processed by the kernel loader. */
1583
1584 /* There are two relocations for the initial PLT entry: an
1585 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 4 and an
1586 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 8. */
1587
1588 if (h->plt.offset == PLT_ENTRY_SIZE)
1589 htab->srelplt2->size += (sizeof (Elf32_External_Rel) * 2);
1590
1591 /* There are two extra relocations for each subsequent PLT entry:
1592 an R_386_32 relocation for the GOT entry, and an R_386_32
1593 relocation for the PLT entry. */
1594
1595 htab->srelplt2->size += (sizeof (Elf32_External_Rel) * 2);
1596 }
1597 }
1598 else
1599 {
1600 h->plt.offset = (bfd_vma) -1;
1601 h->needs_plt = 0;
1602 }
1603 }
1604 else
1605 {
1606 h->plt.offset = (bfd_vma) -1;
1607 h->needs_plt = 0;
1608 }
1609
1610 /* If R_386_TLS_{IE_32,IE,GOTIE} symbol is now local to the binary,
1611 make it a R_386_TLS_LE_32 requiring no TLS entry. */
1612 if (h->got.refcount > 0
1613 && !info->shared
1614 && h->dynindx == -1
1615 && (elf_i386_hash_entry(h)->tls_type & GOT_TLS_IE))
1616 h->got.offset = (bfd_vma) -1;
1617 else if (h->got.refcount > 0)
1618 {
1619 asection *s;
1620 bfd_boolean dyn;
1621 int tls_type = elf_i386_hash_entry(h)->tls_type;
1622
1623 /* Make sure this symbol is output as a dynamic symbol.
1624 Undefined weak syms won't yet be marked as dynamic. */
1625 if (h->dynindx == -1
1626 && !h->forced_local)
1627 {
1628 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1629 return FALSE;
1630 }
1631
1632 s = htab->sgot;
1633 h->got.offset = s->size;
1634 s->size += 4;
1635 /* R_386_TLS_GD needs 2 consecutive GOT slots. */
1636 if (tls_type == GOT_TLS_GD || tls_type == GOT_TLS_IE_BOTH)
1637 s->size += 4;
1638 dyn = htab->elf.dynamic_sections_created;
1639 /* R_386_TLS_IE_32 needs one dynamic relocation,
1640 R_386_TLS_IE resp. R_386_TLS_GOTIE needs one dynamic relocation,
1641 (but if both R_386_TLS_IE_32 and R_386_TLS_IE is present, we
1642 need two), R_386_TLS_GD needs one if local symbol and two if
1643 global. */
1644 if (tls_type == GOT_TLS_IE_BOTH)
1645 htab->srelgot->size += 2 * sizeof (Elf32_External_Rel);
1646 else if ((tls_type == GOT_TLS_GD && h->dynindx == -1)
1647 || (tls_type & GOT_TLS_IE))
1648 htab->srelgot->size += sizeof (Elf32_External_Rel);
1649 else if (tls_type == GOT_TLS_GD)
1650 htab->srelgot->size += 2 * sizeof (Elf32_External_Rel);
1651 else if ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1652 || h->root.type != bfd_link_hash_undefweak)
1653 && (info->shared
1654 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
1655 htab->srelgot->size += sizeof (Elf32_External_Rel);
1656 }
1657 else
1658 h->got.offset = (bfd_vma) -1;
1659
1660 eh = (struct elf_i386_link_hash_entry *) h;
1661 if (eh->dyn_relocs == NULL)
1662 return TRUE;
1663
1664 /* In the shared -Bsymbolic case, discard space allocated for
1665 dynamic pc-relative relocs against symbols which turn out to be
1666 defined in regular objects. For the normal shared case, discard
1667 space for pc-relative relocs that have become local due to symbol
1668 visibility changes. */
1669
1670 if (info->shared)
1671 {
1672 /* The only reloc that uses pc_count is R_386_PC32, which will
1673 appear on a call or on something like ".long foo - .". We
1674 want calls to protected symbols to resolve directly to the
1675 function rather than going via the plt. If people want
1676 function pointer comparisons to work as expected then they
1677 should avoid writing assembly like ".long foo - .". */
1678 if (SYMBOL_CALLS_LOCAL (info, h))
1679 {
1680 struct elf_i386_dyn_relocs **pp;
1681
1682 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1683 {
1684 p->count -= p->pc_count;
1685 p->pc_count = 0;
1686 if (p->count == 0)
1687 *pp = p->next;
1688 else
1689 pp = &p->next;
1690 }
1691 }
1692
1693 /* Also discard relocs on undefined weak syms with non-default
1694 visibility. */
1695 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1696 && h->root.type == bfd_link_hash_undefweak)
1697 eh->dyn_relocs = NULL;
1698 }
1699 else if (ELIMINATE_COPY_RELOCS)
1700 {
1701 /* For the non-shared case, discard space for relocs against
1702 symbols which turn out to need copy relocs or are not
1703 dynamic. */
1704
1705 if (!h->non_got_ref
1706 && ((h->def_dynamic
1707 && !h->def_regular)
1708 || (htab->elf.dynamic_sections_created
1709 && (h->root.type == bfd_link_hash_undefweak
1710 || h->root.type == bfd_link_hash_undefined))))
1711 {
1712 /* Make sure this symbol is output as a dynamic symbol.
1713 Undefined weak syms won't yet be marked as dynamic. */
1714 if (h->dynindx == -1
1715 && !h->forced_local)
1716 {
1717 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1718 return FALSE;
1719 }
1720
1721 /* If that succeeded, we know we'll be keeping all the
1722 relocs. */
1723 if (h->dynindx != -1)
1724 goto keep;
1725 }
1726
1727 eh->dyn_relocs = NULL;
1728
1729 keep: ;
1730 }
1731
1732 /* Finally, allocate space. */
1733 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1734 {
1735 asection *sreloc = elf_section_data (p->sec)->sreloc;
1736 sreloc->size += p->count * sizeof (Elf32_External_Rel);
1737 }
1738
1739 return TRUE;
1740 }
1741
1742 /* Find any dynamic relocs that apply to read-only sections. */
1743
1744 static bfd_boolean
1745 readonly_dynrelocs (struct elf_link_hash_entry *h, void *inf)
1746 {
1747 struct elf_i386_link_hash_entry *eh;
1748 struct elf_i386_dyn_relocs *p;
1749
1750 if (h->root.type == bfd_link_hash_warning)
1751 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1752
1753 eh = (struct elf_i386_link_hash_entry *) h;
1754 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1755 {
1756 asection *s = p->sec->output_section;
1757
1758 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1759 {
1760 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1761
1762 info->flags |= DF_TEXTREL;
1763
1764 /* Not an error, just cut short the traversal. */
1765 return FALSE;
1766 }
1767 }
1768 return TRUE;
1769 }
1770
1771 /* Set the sizes of the dynamic sections. */
1772
1773 static bfd_boolean
1774 elf_i386_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
1775 struct bfd_link_info *info)
1776 {
1777 struct elf_i386_link_hash_table *htab;
1778 bfd *dynobj;
1779 asection *s;
1780 bfd_boolean relocs;
1781 bfd *ibfd;
1782
1783 htab = elf_i386_hash_table (info);
1784 dynobj = htab->elf.dynobj;
1785 if (dynobj == NULL)
1786 abort ();
1787
1788 if (htab->elf.dynamic_sections_created)
1789 {
1790 /* Set the contents of the .interp section to the interpreter. */
1791 if (info->executable)
1792 {
1793 s = bfd_get_section_by_name (dynobj, ".interp");
1794 if (s == NULL)
1795 abort ();
1796 s->size = sizeof ELF_DYNAMIC_INTERPRETER;
1797 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1798 }
1799 }
1800
1801 /* Set up .got offsets for local syms, and space for local dynamic
1802 relocs. */
1803 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1804 {
1805 bfd_signed_vma *local_got;
1806 bfd_signed_vma *end_local_got;
1807 char *local_tls_type;
1808 bfd_size_type locsymcount;
1809 Elf_Internal_Shdr *symtab_hdr;
1810 asection *srel;
1811
1812 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1813 continue;
1814
1815 for (s = ibfd->sections; s != NULL; s = s->next)
1816 {
1817 struct elf_i386_dyn_relocs *p;
1818
1819 for (p = *((struct elf_i386_dyn_relocs **)
1820 &elf_section_data (s)->local_dynrel);
1821 p != NULL;
1822 p = p->next)
1823 {
1824 if (!bfd_is_abs_section (p->sec)
1825 && bfd_is_abs_section (p->sec->output_section))
1826 {
1827 /* Input section has been discarded, either because
1828 it is a copy of a linkonce section or due to
1829 linker script /DISCARD/, so we'll be discarding
1830 the relocs too. */
1831 }
1832 else if (p->count != 0)
1833 {
1834 srel = elf_section_data (p->sec)->sreloc;
1835 srel->size += p->count * sizeof (Elf32_External_Rel);
1836 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1837 info->flags |= DF_TEXTREL;
1838 }
1839 }
1840 }
1841
1842 local_got = elf_local_got_refcounts (ibfd);
1843 if (!local_got)
1844 continue;
1845
1846 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1847 locsymcount = symtab_hdr->sh_info;
1848 end_local_got = local_got + locsymcount;
1849 local_tls_type = elf_i386_local_got_tls_type (ibfd);
1850 s = htab->sgot;
1851 srel = htab->srelgot;
1852 for (; local_got < end_local_got; ++local_got, ++local_tls_type)
1853 {
1854 if (*local_got > 0)
1855 {
1856 *local_got = s->size;
1857 s->size += 4;
1858 if (*local_tls_type == GOT_TLS_GD
1859 || *local_tls_type == GOT_TLS_IE_BOTH)
1860 s->size += 4;
1861 if (info->shared
1862 || *local_tls_type == GOT_TLS_GD
1863 || (*local_tls_type & GOT_TLS_IE))
1864 {
1865 if (*local_tls_type == GOT_TLS_IE_BOTH)
1866 srel->size += 2 * sizeof (Elf32_External_Rel);
1867 else
1868 srel->size += sizeof (Elf32_External_Rel);
1869 }
1870 }
1871 else
1872 *local_got = (bfd_vma) -1;
1873 }
1874 }
1875
1876 if (htab->tls_ldm_got.refcount > 0)
1877 {
1878 /* Allocate 2 got entries and 1 dynamic reloc for R_386_TLS_LDM
1879 relocs. */
1880 htab->tls_ldm_got.offset = htab->sgot->size;
1881 htab->sgot->size += 8;
1882 htab->srelgot->size += sizeof (Elf32_External_Rel);
1883 }
1884 else
1885 htab->tls_ldm_got.offset = -1;
1886
1887 if (htab->is_vxworks)
1888 {
1889 /* Save the GOT and PLT symbols in the hash table for easy access.
1890 Mark them as having relocations; they might not, but we won't
1891 know for sure until we build the GOT in finish_dynamic_symbol. */
1892
1893 htab->hgot = elf_link_hash_lookup (elf_hash_table (info),
1894 "_GLOBAL_OFFSET_TABLE_",
1895 FALSE, FALSE, FALSE);
1896 if (htab->hgot)
1897 htab->hgot->indx = -2;
1898 htab->hplt = elf_link_hash_lookup (elf_hash_table (info),
1899 "_PROCEDURE_LINKAGE_TABLE_",
1900 FALSE, FALSE, FALSE);
1901 if (htab->hplt)
1902 htab->hplt->indx = -2;
1903
1904 if (htab->is_vxworks && htab->hplt && htab->splt->flags & SEC_CODE)
1905 htab->hplt->type = STT_FUNC;
1906 }
1907
1908 /* Allocate global sym .plt and .got entries, and space for global
1909 sym dynamic relocs. */
1910 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1911
1912 /* We now have determined the sizes of the various dynamic sections.
1913 Allocate memory for them. */
1914 relocs = FALSE;
1915 for (s = dynobj->sections; s != NULL; s = s->next)
1916 {
1917 bfd_boolean strip_section = TRUE;
1918
1919 if ((s->flags & SEC_LINKER_CREATED) == 0)
1920 continue;
1921
1922 if (s == htab->splt
1923 || s == htab->sgot
1924 || s == htab->sgotplt
1925 || s == htab->sdynbss)
1926 {
1927 /* Strip this section if we don't need it; see the
1928 comment below. */
1929 /* We'd like to strip these sections if they aren't needed, but if
1930 we've exported dynamic symbols from them we must leave them.
1931 It's too late to tell BFD to get rid of the symbols. */
1932
1933 if (htab->hplt != NULL)
1934 strip_section = FALSE;
1935 }
1936 else if (strncmp (bfd_get_section_name (dynobj, s), ".rel", 4) == 0)
1937 {
1938 if (s->size != 0 && s != htab->srelplt && s != htab->srelplt2)
1939 relocs = TRUE;
1940
1941 /* We use the reloc_count field as a counter if we need
1942 to copy relocs into the output file. */
1943 s->reloc_count = 0;
1944 }
1945 else
1946 {
1947 /* It's not one of our sections, so don't allocate space. */
1948 continue;
1949 }
1950
1951 if (s->size == 0 && strip_section)
1952 {
1953 /* If we don't need this section, strip it from the
1954 output file. This is mostly to handle .rel.bss and
1955 .rel.plt. We must create both sections in
1956 create_dynamic_sections, because they must be created
1957 before the linker maps input sections to output
1958 sections. The linker does that before
1959 adjust_dynamic_symbol is called, and it is that
1960 function which decides whether anything needs to go
1961 into these sections. */
1962
1963 s->flags |= SEC_EXCLUDE;
1964 continue;
1965 }
1966
1967 /* Allocate memory for the section contents. We use bfd_zalloc
1968 here in case unused entries are not reclaimed before the
1969 section's contents are written out. This should not happen,
1970 but this way if it does, we get a R_386_NONE reloc instead
1971 of garbage. */
1972 s->contents = bfd_zalloc (dynobj, s->size);
1973 if (s->contents == NULL)
1974 return FALSE;
1975 }
1976
1977 if (htab->elf.dynamic_sections_created)
1978 {
1979 /* Add some entries to the .dynamic section. We fill in the
1980 values later, in elf_i386_finish_dynamic_sections, but we
1981 must add the entries now so that we get the correct size for
1982 the .dynamic section. The DT_DEBUG entry is filled in by the
1983 dynamic linker and used by the debugger. */
1984 #define add_dynamic_entry(TAG, VAL) \
1985 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1986
1987 if (info->executable)
1988 {
1989 if (!add_dynamic_entry (DT_DEBUG, 0))
1990 return FALSE;
1991 }
1992
1993 if (htab->splt->size != 0)
1994 {
1995 if (!add_dynamic_entry (DT_PLTGOT, 0)
1996 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1997 || !add_dynamic_entry (DT_PLTREL, DT_REL)
1998 || !add_dynamic_entry (DT_JMPREL, 0))
1999 return FALSE;
2000 }
2001
2002 if (relocs)
2003 {
2004 if (!add_dynamic_entry (DT_REL, 0)
2005 || !add_dynamic_entry (DT_RELSZ, 0)
2006 || !add_dynamic_entry (DT_RELENT, sizeof (Elf32_External_Rel)))
2007 return FALSE;
2008
2009 /* If any dynamic relocs apply to a read-only section,
2010 then we need a DT_TEXTREL entry. */
2011 if ((info->flags & DF_TEXTREL) == 0)
2012 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
2013 (PTR) info);
2014
2015 if ((info->flags & DF_TEXTREL) != 0)
2016 {
2017 if (!add_dynamic_entry (DT_TEXTREL, 0))
2018 return FALSE;
2019 }
2020 }
2021 }
2022 #undef add_dynamic_entry
2023
2024 return TRUE;
2025 }
2026
2027 /* Set the correct type for an x86 ELF section. We do this by the
2028 section name, which is a hack, but ought to work. */
2029
2030 static bfd_boolean
2031 elf_i386_fake_sections (bfd *abfd ATTRIBUTE_UNUSED,
2032 Elf_Internal_Shdr *hdr,
2033 asection *sec)
2034 {
2035 register const char *name;
2036
2037 name = bfd_get_section_name (abfd, sec);
2038
2039 /* This is an ugly, but unfortunately necessary hack that is
2040 needed when producing EFI binaries on x86. It tells
2041 elf.c:elf_fake_sections() not to consider ".reloc" as a section
2042 containing ELF relocation info. We need this hack in order to
2043 be able to generate ELF binaries that can be translated into
2044 EFI applications (which are essentially COFF objects). Those
2045 files contain a COFF ".reloc" section inside an ELFNN object,
2046 which would normally cause BFD to segfault because it would
2047 attempt to interpret this section as containing relocation
2048 entries for section "oc". With this hack enabled, ".reloc"
2049 will be treated as a normal data section, which will avoid the
2050 segfault. However, you won't be able to create an ELFNN binary
2051 with a section named "oc" that needs relocations, but that's
2052 the kind of ugly side-effects you get when detecting section
2053 types based on their names... In practice, this limitation is
2054 unlikely to bite. */
2055 if (strcmp (name, ".reloc") == 0)
2056 hdr->sh_type = SHT_PROGBITS;
2057
2058 return TRUE;
2059 }
2060
2061 /* Return the base VMA address which should be subtracted from real addresses
2062 when resolving @dtpoff relocation.
2063 This is PT_TLS segment p_vaddr. */
2064
2065 static bfd_vma
2066 dtpoff_base (struct bfd_link_info *info)
2067 {
2068 /* If tls_sec is NULL, we should have signalled an error already. */
2069 if (elf_hash_table (info)->tls_sec == NULL)
2070 return 0;
2071 return elf_hash_table (info)->tls_sec->vma;
2072 }
2073
2074 /* Return the relocation value for @tpoff relocation
2075 if STT_TLS virtual address is ADDRESS. */
2076
2077 static bfd_vma
2078 tpoff (struct bfd_link_info *info, bfd_vma address)
2079 {
2080 struct elf_link_hash_table *htab = elf_hash_table (info);
2081
2082 /* If tls_sec is NULL, we should have signalled an error already. */
2083 if (htab->tls_sec == NULL)
2084 return 0;
2085 return htab->tls_size + htab->tls_sec->vma - address;
2086 }
2087
2088 /* Relocate an i386 ELF section. */
2089
2090 static bfd_boolean
2091 elf_i386_relocate_section (bfd *output_bfd,
2092 struct bfd_link_info *info,
2093 bfd *input_bfd,
2094 asection *input_section,
2095 bfd_byte *contents,
2096 Elf_Internal_Rela *relocs,
2097 Elf_Internal_Sym *local_syms,
2098 asection **local_sections)
2099 {
2100 struct elf_i386_link_hash_table *htab;
2101 Elf_Internal_Shdr *symtab_hdr;
2102 struct elf_link_hash_entry **sym_hashes;
2103 bfd_vma *local_got_offsets;
2104 Elf_Internal_Rela *rel;
2105 Elf_Internal_Rela *relend;
2106
2107 htab = elf_i386_hash_table (info);
2108 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2109 sym_hashes = elf_sym_hashes (input_bfd);
2110 local_got_offsets = elf_local_got_offsets (input_bfd);
2111
2112 rel = relocs;
2113 relend = relocs + input_section->reloc_count;
2114 for (; rel < relend; rel++)
2115 {
2116 unsigned int r_type;
2117 reloc_howto_type *howto;
2118 unsigned long r_symndx;
2119 struct elf_link_hash_entry *h;
2120 Elf_Internal_Sym *sym;
2121 asection *sec;
2122 bfd_vma off;
2123 bfd_vma relocation;
2124 bfd_boolean unresolved_reloc;
2125 bfd_reloc_status_type r;
2126 unsigned int indx;
2127 int tls_type;
2128
2129 r_type = ELF32_R_TYPE (rel->r_info);
2130 if (r_type == R_386_GNU_VTINHERIT
2131 || r_type == R_386_GNU_VTENTRY)
2132 continue;
2133
2134 if ((indx = r_type) >= R_386_standard
2135 && ((indx = r_type - R_386_ext_offset) - R_386_standard
2136 >= R_386_ext - R_386_standard)
2137 && ((indx = r_type - R_386_tls_offset) - R_386_ext
2138 >= R_386_tls - R_386_ext))
2139 {
2140 (*_bfd_error_handler)
2141 (_("%B: unrecognized relocation (0x%x) in section `%A'"),
2142 input_bfd, input_section, r_type);
2143 bfd_set_error (bfd_error_bad_value);
2144 return FALSE;
2145 }
2146 howto = elf_howto_table + indx;
2147
2148 r_symndx = ELF32_R_SYM (rel->r_info);
2149
2150 if (info->relocatable)
2151 {
2152 bfd_vma val;
2153 bfd_byte *where;
2154
2155 /* This is a relocatable link. We don't have to change
2156 anything, unless the reloc is against a section symbol,
2157 in which case we have to adjust according to where the
2158 section symbol winds up in the output section. */
2159 if (r_symndx >= symtab_hdr->sh_info)
2160 continue;
2161
2162 sym = local_syms + r_symndx;
2163 if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
2164 continue;
2165
2166 sec = local_sections[r_symndx];
2167 val = sec->output_offset;
2168 if (val == 0)
2169 continue;
2170
2171 where = contents + rel->r_offset;
2172 switch (howto->size)
2173 {
2174 /* FIXME: overflow checks. */
2175 case 0:
2176 val += bfd_get_8 (input_bfd, where);
2177 bfd_put_8 (input_bfd, val, where);
2178 break;
2179 case 1:
2180 val += bfd_get_16 (input_bfd, where);
2181 bfd_put_16 (input_bfd, val, where);
2182 break;
2183 case 2:
2184 val += bfd_get_32 (input_bfd, where);
2185 bfd_put_32 (input_bfd, val, where);
2186 break;
2187 default:
2188 abort ();
2189 }
2190 continue;
2191 }
2192
2193 /* This is a final link. */
2194 h = NULL;
2195 sym = NULL;
2196 sec = NULL;
2197 unresolved_reloc = FALSE;
2198 if (r_symndx < symtab_hdr->sh_info)
2199 {
2200 sym = local_syms + r_symndx;
2201 sec = local_sections[r_symndx];
2202 relocation = (sec->output_section->vma
2203 + sec->output_offset
2204 + sym->st_value);
2205 if ((sec->flags & SEC_MERGE)
2206 && ELF_ST_TYPE (sym->st_info) == STT_SECTION)
2207 {
2208 asection *msec;
2209 bfd_vma addend;
2210 bfd_byte *where = contents + rel->r_offset;
2211
2212 switch (howto->size)
2213 {
2214 case 0:
2215 addend = bfd_get_8 (input_bfd, where);
2216 if (howto->pc_relative)
2217 {
2218 addend = (addend ^ 0x80) - 0x80;
2219 addend += 1;
2220 }
2221 break;
2222 case 1:
2223 addend = bfd_get_16 (input_bfd, where);
2224 if (howto->pc_relative)
2225 {
2226 addend = (addend ^ 0x8000) - 0x8000;
2227 addend += 2;
2228 }
2229 break;
2230 case 2:
2231 addend = bfd_get_32 (input_bfd, where);
2232 if (howto->pc_relative)
2233 {
2234 addend = (addend ^ 0x80000000) - 0x80000000;
2235 addend += 4;
2236 }
2237 break;
2238 default:
2239 abort ();
2240 }
2241
2242 msec = sec;
2243 addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec, addend);
2244 addend -= relocation;
2245 addend += msec->output_section->vma + msec->output_offset;
2246
2247 switch (howto->size)
2248 {
2249 case 0:
2250 /* FIXME: overflow checks. */
2251 if (howto->pc_relative)
2252 addend -= 1;
2253 bfd_put_8 (input_bfd, addend, where);
2254 break;
2255 case 1:
2256 if (howto->pc_relative)
2257 addend -= 2;
2258 bfd_put_16 (input_bfd, addend, where);
2259 break;
2260 case 2:
2261 if (howto->pc_relative)
2262 addend -= 4;
2263 bfd_put_32 (input_bfd, addend, where);
2264 break;
2265 }
2266 }
2267 }
2268 else
2269 {
2270 bfd_boolean warned;
2271
2272 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
2273 r_symndx, symtab_hdr, sym_hashes,
2274 h, sec, relocation,
2275 unresolved_reloc, warned);
2276 }
2277
2278 if (r_symndx == 0)
2279 {
2280 /* r_symndx will be zero only for relocs against symbols from
2281 removed linkonce sections, or sections discarded by a linker
2282 script. For these relocs, we just want the section contents
2283 zeroed. Avoid any special processing in the switch below. */
2284 r_type = R_386_NONE;
2285
2286 relocation = 0;
2287 if (howto->pc_relative)
2288 relocation = (input_section->output_section->vma
2289 + input_section->output_offset
2290 + rel->r_offset);
2291 }
2292
2293 switch (r_type)
2294 {
2295 case R_386_GOT32:
2296 /* Relocation is to the entry for this symbol in the global
2297 offset table. */
2298 if (htab->sgot == NULL)
2299 abort ();
2300
2301 if (h != NULL)
2302 {
2303 bfd_boolean dyn;
2304
2305 off = h->got.offset;
2306 dyn = htab->elf.dynamic_sections_created;
2307 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
2308 || (info->shared
2309 && SYMBOL_REFERENCES_LOCAL (info, h))
2310 || (ELF_ST_VISIBILITY (h->other)
2311 && h->root.type == bfd_link_hash_undefweak))
2312 {
2313 /* This is actually a static link, or it is a
2314 -Bsymbolic link and the symbol is defined
2315 locally, or the symbol was forced to be local
2316 because of a version file. We must initialize
2317 this entry in the global offset table. Since the
2318 offset must always be a multiple of 4, we use the
2319 least significant bit to record whether we have
2320 initialized it already.
2321
2322 When doing a dynamic link, we create a .rel.got
2323 relocation entry to initialize the value. This
2324 is done in the finish_dynamic_symbol routine. */
2325 if ((off & 1) != 0)
2326 off &= ~1;
2327 else
2328 {
2329 bfd_put_32 (output_bfd, relocation,
2330 htab->sgot->contents + off);
2331 h->got.offset |= 1;
2332 }
2333 }
2334 else
2335 unresolved_reloc = FALSE;
2336 }
2337 else
2338 {
2339 if (local_got_offsets == NULL)
2340 abort ();
2341
2342 off = local_got_offsets[r_symndx];
2343
2344 /* The offset must always be a multiple of 4. We use
2345 the least significant bit to record whether we have
2346 already generated the necessary reloc. */
2347 if ((off & 1) != 0)
2348 off &= ~1;
2349 else
2350 {
2351 bfd_put_32 (output_bfd, relocation,
2352 htab->sgot->contents + off);
2353
2354 if (info->shared)
2355 {
2356 asection *s;
2357 Elf_Internal_Rela outrel;
2358 bfd_byte *loc;
2359
2360 s = htab->srelgot;
2361 if (s == NULL)
2362 abort ();
2363
2364 outrel.r_offset = (htab->sgot->output_section->vma
2365 + htab->sgot->output_offset
2366 + off);
2367 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2368 loc = s->contents;
2369 loc += s->reloc_count++ * sizeof (Elf32_External_Rel);
2370 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2371 }
2372
2373 local_got_offsets[r_symndx] |= 1;
2374 }
2375 }
2376
2377 if (off >= (bfd_vma) -2)
2378 abort ();
2379
2380 relocation = htab->sgot->output_section->vma
2381 + htab->sgot->output_offset + off
2382 - htab->sgotplt->output_section->vma
2383 - htab->sgotplt->output_offset;
2384 break;
2385
2386 case R_386_GOTOFF:
2387 /* Relocation is relative to the start of the global offset
2388 table. */
2389
2390 /* Check to make sure it isn't a protected function symbol
2391 for shared library since it may not be local when used
2392 as function address. */
2393 if (info->shared
2394 && !info->executable
2395 && h
2396 && h->def_regular
2397 && h->type == STT_FUNC
2398 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
2399 {
2400 (*_bfd_error_handler)
2401 (_("%B: relocation R_386_GOTOFF against protected function `%s' can not be used when making a shared object"),
2402 input_bfd, h->root.root.string);
2403 bfd_set_error (bfd_error_bad_value);
2404 return FALSE;
2405 }
2406
2407 /* Note that sgot is not involved in this
2408 calculation. We always want the start of .got.plt. If we
2409 defined _GLOBAL_OFFSET_TABLE_ in a different way, as is
2410 permitted by the ABI, we might have to change this
2411 calculation. */
2412 relocation -= htab->sgotplt->output_section->vma
2413 + htab->sgotplt->output_offset;
2414 break;
2415
2416 case R_386_GOTPC:
2417 /* Use global offset table as symbol value. */
2418 relocation = htab->sgotplt->output_section->vma
2419 + htab->sgotplt->output_offset;
2420 unresolved_reloc = FALSE;
2421 break;
2422
2423 case R_386_PLT32:
2424 /* Relocation is to the entry for this symbol in the
2425 procedure linkage table. */
2426
2427 /* Resolve a PLT32 reloc against a local symbol directly,
2428 without using the procedure linkage table. */
2429 if (h == NULL)
2430 break;
2431
2432 if (h->plt.offset == (bfd_vma) -1
2433 || htab->splt == NULL)
2434 {
2435 /* We didn't make a PLT entry for this symbol. This
2436 happens when statically linking PIC code, or when
2437 using -Bsymbolic. */
2438 break;
2439 }
2440
2441 relocation = (htab->splt->output_section->vma
2442 + htab->splt->output_offset
2443 + h->plt.offset);
2444 unresolved_reloc = FALSE;
2445 break;
2446
2447 case R_386_32:
2448 case R_386_PC32:
2449 if ((input_section->flags & SEC_ALLOC) == 0)
2450 break;
2451
2452 if ((info->shared
2453 && (h == NULL
2454 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
2455 || h->root.type != bfd_link_hash_undefweak)
2456 && (r_type != R_386_PC32
2457 || !SYMBOL_CALLS_LOCAL (info, h)))
2458 || (ELIMINATE_COPY_RELOCS
2459 && !info->shared
2460 && h != NULL
2461 && h->dynindx != -1
2462 && !h->non_got_ref
2463 && ((h->def_dynamic
2464 && !h->def_regular)
2465 || h->root.type == bfd_link_hash_undefweak
2466 || h->root.type == bfd_link_hash_undefined)))
2467 {
2468 Elf_Internal_Rela outrel;
2469 bfd_byte *loc;
2470 bfd_boolean skip, relocate;
2471 asection *sreloc;
2472
2473 /* When generating a shared object, these relocations
2474 are copied into the output file to be resolved at run
2475 time. */
2476
2477 skip = FALSE;
2478 relocate = FALSE;
2479
2480 outrel.r_offset =
2481 _bfd_elf_section_offset (output_bfd, info, input_section,
2482 rel->r_offset);
2483 if (outrel.r_offset == (bfd_vma) -1)
2484 skip = TRUE;
2485 else if (outrel.r_offset == (bfd_vma) -2)
2486 skip = TRUE, relocate = TRUE;
2487 outrel.r_offset += (input_section->output_section->vma
2488 + input_section->output_offset);
2489
2490 if (skip)
2491 memset (&outrel, 0, sizeof outrel);
2492 else if (h != NULL
2493 && h->dynindx != -1
2494 && (r_type == R_386_PC32
2495 || !info->shared
2496 || !info->symbolic
2497 || !h->def_regular))
2498 outrel.r_info = ELF32_R_INFO (h->dynindx, r_type);
2499 else
2500 {
2501 /* This symbol is local, or marked to become local. */
2502 relocate = TRUE;
2503 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2504 }
2505
2506 sreloc = elf_section_data (input_section)->sreloc;
2507 if (sreloc == NULL)
2508 abort ();
2509
2510 loc = sreloc->contents;
2511 loc += sreloc->reloc_count++ * sizeof (Elf32_External_Rel);
2512 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2513
2514 /* If this reloc is against an external symbol, we do
2515 not want to fiddle with the addend. Otherwise, we
2516 need to include the symbol value so that it becomes
2517 an addend for the dynamic reloc. */
2518 if (! relocate)
2519 continue;
2520 }
2521 break;
2522
2523 case R_386_TLS_IE:
2524 if (info->shared)
2525 {
2526 Elf_Internal_Rela outrel;
2527 bfd_byte *loc;
2528 asection *sreloc;
2529
2530 outrel.r_offset = rel->r_offset
2531 + input_section->output_section->vma
2532 + input_section->output_offset;
2533 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2534 sreloc = elf_section_data (input_section)->sreloc;
2535 if (sreloc == NULL)
2536 abort ();
2537 loc = sreloc->contents;
2538 loc += sreloc->reloc_count++ * sizeof (Elf32_External_Rel);
2539 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2540 }
2541 /* Fall through */
2542
2543 case R_386_TLS_GD:
2544 case R_386_TLS_IE_32:
2545 case R_386_TLS_GOTIE:
2546 r_type = elf_i386_tls_transition (info, r_type, h == NULL);
2547 tls_type = GOT_UNKNOWN;
2548 if (h == NULL && local_got_offsets)
2549 tls_type = elf_i386_local_got_tls_type (input_bfd) [r_symndx];
2550 else if (h != NULL)
2551 {
2552 tls_type = elf_i386_hash_entry(h)->tls_type;
2553 if (!info->shared && h->dynindx == -1 && (tls_type & GOT_TLS_IE))
2554 r_type = R_386_TLS_LE_32;
2555 }
2556 if (tls_type == GOT_TLS_IE)
2557 tls_type = GOT_TLS_IE_NEG;
2558 if (r_type == R_386_TLS_GD)
2559 {
2560 if (tls_type == GOT_TLS_IE_POS)
2561 r_type = R_386_TLS_GOTIE;
2562 else if (tls_type & GOT_TLS_IE)
2563 r_type = R_386_TLS_IE_32;
2564 }
2565
2566 if (r_type == R_386_TLS_LE_32)
2567 {
2568 BFD_ASSERT (! unresolved_reloc);
2569 if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GD)
2570 {
2571 unsigned int val, type;
2572 bfd_vma roff;
2573
2574 /* GD->LE transition. */
2575 BFD_ASSERT (rel->r_offset >= 2);
2576 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2577 BFD_ASSERT (type == 0x8d || type == 0x04);
2578 BFD_ASSERT (rel->r_offset + 9 <= input_section->size);
2579 BFD_ASSERT (bfd_get_8 (input_bfd,
2580 contents + rel->r_offset + 4)
2581 == 0xe8);
2582 BFD_ASSERT (rel + 1 < relend);
2583 BFD_ASSERT (ELF32_R_TYPE (rel[1].r_info) == R_386_PLT32);
2584 roff = rel->r_offset + 5;
2585 val = bfd_get_8 (input_bfd,
2586 contents + rel->r_offset - 1);
2587 if (type == 0x04)
2588 {
2589 /* leal foo(,%reg,1), %eax; call ___tls_get_addr
2590 Change it into:
2591 movl %gs:0, %eax; subl $foo@tpoff, %eax
2592 (6 byte form of subl). */
2593 BFD_ASSERT (rel->r_offset >= 3);
2594 BFD_ASSERT (bfd_get_8 (input_bfd,
2595 contents + rel->r_offset - 3)
2596 == 0x8d);
2597 BFD_ASSERT ((val & 0xc7) == 0x05 && val != (4 << 3));
2598 memcpy (contents + rel->r_offset - 3,
2599 "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2600 }
2601 else
2602 {
2603 BFD_ASSERT ((val & 0xf8) == 0x80 && (val & 7) != 4);
2604 if (rel->r_offset + 10 <= input_section->size
2605 && bfd_get_8 (input_bfd,
2606 contents + rel->r_offset + 9) == 0x90)
2607 {
2608 /* leal foo(%reg), %eax; call ___tls_get_addr; nop
2609 Change it into:
2610 movl %gs:0, %eax; subl $foo@tpoff, %eax
2611 (6 byte form of subl). */
2612 memcpy (contents + rel->r_offset - 2,
2613 "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2614 roff = rel->r_offset + 6;
2615 }
2616 else
2617 {
2618 /* leal foo(%reg), %eax; call ___tls_get_addr
2619 Change it into:
2620 movl %gs:0, %eax; subl $foo@tpoff, %eax
2621 (5 byte form of subl). */
2622 memcpy (contents + rel->r_offset - 2,
2623 "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2624 }
2625 }
2626 bfd_put_32 (output_bfd, tpoff (info, relocation),
2627 contents + roff);
2628 /* Skip R_386_PLT32. */
2629 rel++;
2630 continue;
2631 }
2632 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_IE)
2633 {
2634 unsigned int val, type;
2635
2636 /* IE->LE transition:
2637 Originally it can be one of:
2638 movl foo, %eax
2639 movl foo, %reg
2640 addl foo, %reg
2641 We change it into:
2642 movl $foo, %eax
2643 movl $foo, %reg
2644 addl $foo, %reg. */
2645 BFD_ASSERT (rel->r_offset >= 1);
2646 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2647 BFD_ASSERT (rel->r_offset + 4 <= input_section->size);
2648 if (val == 0xa1)
2649 {
2650 /* movl foo, %eax. */
2651 bfd_put_8 (output_bfd, 0xb8,
2652 contents + rel->r_offset - 1);
2653 }
2654 else
2655 {
2656 BFD_ASSERT (rel->r_offset >= 2);
2657 type = bfd_get_8 (input_bfd,
2658 contents + rel->r_offset - 2);
2659 switch (type)
2660 {
2661 case 0x8b:
2662 /* movl */
2663 BFD_ASSERT ((val & 0xc7) == 0x05);
2664 bfd_put_8 (output_bfd, 0xc7,
2665 contents + rel->r_offset - 2);
2666 bfd_put_8 (output_bfd,
2667 0xc0 | ((val >> 3) & 7),
2668 contents + rel->r_offset - 1);
2669 break;
2670 case 0x03:
2671 /* addl */
2672 BFD_ASSERT ((val & 0xc7) == 0x05);
2673 bfd_put_8 (output_bfd, 0x81,
2674 contents + rel->r_offset - 2);
2675 bfd_put_8 (output_bfd,
2676 0xc0 | ((val >> 3) & 7),
2677 contents + rel->r_offset - 1);
2678 break;
2679 default:
2680 BFD_FAIL ();
2681 break;
2682 }
2683 }
2684 bfd_put_32 (output_bfd, -tpoff (info, relocation),
2685 contents + rel->r_offset);
2686 continue;
2687 }
2688 else
2689 {
2690 unsigned int val, type;
2691
2692 /* {IE_32,GOTIE}->LE transition:
2693 Originally it can be one of:
2694 subl foo(%reg1), %reg2
2695 movl foo(%reg1), %reg2
2696 addl foo(%reg1), %reg2
2697 We change it into:
2698 subl $foo, %reg2
2699 movl $foo, %reg2 (6 byte form)
2700 addl $foo, %reg2. */
2701 BFD_ASSERT (rel->r_offset >= 2);
2702 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2703 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2704 BFD_ASSERT (rel->r_offset + 4 <= input_section->size);
2705 BFD_ASSERT ((val & 0xc0) == 0x80 && (val & 7) != 4);
2706 if (type == 0x8b)
2707 {
2708 /* movl */
2709 bfd_put_8 (output_bfd, 0xc7,
2710 contents + rel->r_offset - 2);
2711 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7),
2712 contents + rel->r_offset - 1);
2713 }
2714 else if (type == 0x2b)
2715 {
2716 /* subl */
2717 bfd_put_8 (output_bfd, 0x81,
2718 contents + rel->r_offset - 2);
2719 bfd_put_8 (output_bfd, 0xe8 | ((val >> 3) & 7),
2720 contents + rel->r_offset - 1);
2721 }
2722 else if (type == 0x03)
2723 {
2724 /* addl */
2725 bfd_put_8 (output_bfd, 0x81,
2726 contents + rel->r_offset - 2);
2727 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7),
2728 contents + rel->r_offset - 1);
2729 }
2730 else
2731 BFD_FAIL ();
2732 if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GOTIE)
2733 bfd_put_32 (output_bfd, -tpoff (info, relocation),
2734 contents + rel->r_offset);
2735 else
2736 bfd_put_32 (output_bfd, tpoff (info, relocation),
2737 contents + rel->r_offset);
2738 continue;
2739 }
2740 }
2741
2742 if (htab->sgot == NULL)
2743 abort ();
2744
2745 if (h != NULL)
2746 off = h->got.offset;
2747 else
2748 {
2749 if (local_got_offsets == NULL)
2750 abort ();
2751
2752 off = local_got_offsets[r_symndx];
2753 }
2754
2755 if ((off & 1) != 0)
2756 off &= ~1;
2757 else
2758 {
2759 Elf_Internal_Rela outrel;
2760 bfd_byte *loc;
2761 int dr_type, indx;
2762
2763 if (htab->srelgot == NULL)
2764 abort ();
2765
2766 outrel.r_offset = (htab->sgot->output_section->vma
2767 + htab->sgot->output_offset + off);
2768
2769 indx = h && h->dynindx != -1 ? h->dynindx : 0;
2770 if (r_type == R_386_TLS_GD)
2771 dr_type = R_386_TLS_DTPMOD32;
2772 else if (tls_type == GOT_TLS_IE_POS)
2773 dr_type = R_386_TLS_TPOFF;
2774 else
2775 dr_type = R_386_TLS_TPOFF32;
2776 if (dr_type == R_386_TLS_TPOFF && indx == 0)
2777 bfd_put_32 (output_bfd, relocation - dtpoff_base (info),
2778 htab->sgot->contents + off);
2779 else if (dr_type == R_386_TLS_TPOFF32 && indx == 0)
2780 bfd_put_32 (output_bfd, dtpoff_base (info) - relocation,
2781 htab->sgot->contents + off);
2782 else
2783 bfd_put_32 (output_bfd, 0,
2784 htab->sgot->contents + off);
2785 outrel.r_info = ELF32_R_INFO (indx, dr_type);
2786 loc = htab->srelgot->contents;
2787 loc += htab->srelgot->reloc_count++ * sizeof (Elf32_External_Rel);
2788 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2789
2790 if (r_type == R_386_TLS_GD)
2791 {
2792 if (indx == 0)
2793 {
2794 BFD_ASSERT (! unresolved_reloc);
2795 bfd_put_32 (output_bfd,
2796 relocation - dtpoff_base (info),
2797 htab->sgot->contents + off + 4);
2798 }
2799 else
2800 {
2801 bfd_put_32 (output_bfd, 0,
2802 htab->sgot->contents + off + 4);
2803 outrel.r_info = ELF32_R_INFO (indx,
2804 R_386_TLS_DTPOFF32);
2805 outrel.r_offset += 4;
2806 htab->srelgot->reloc_count++;
2807 loc += sizeof (Elf32_External_Rel);
2808 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2809 }
2810 }
2811 else if (tls_type == GOT_TLS_IE_BOTH)
2812 {
2813 bfd_put_32 (output_bfd,
2814 indx == 0 ? relocation - dtpoff_base (info) : 0,
2815 htab->sgot->contents + off + 4);
2816 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF);
2817 outrel.r_offset += 4;
2818 htab->srelgot->reloc_count++;
2819 loc += sizeof (Elf32_External_Rel);
2820 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2821 }
2822
2823 if (h != NULL)
2824 h->got.offset |= 1;
2825 else
2826 local_got_offsets[r_symndx] |= 1;
2827 }
2828
2829 if (off >= (bfd_vma) -2)
2830 abort ();
2831 if (r_type == ELF32_R_TYPE (rel->r_info))
2832 {
2833 bfd_vma g_o_t = htab->sgotplt->output_section->vma
2834 + htab->sgotplt->output_offset;
2835 relocation = htab->sgot->output_section->vma
2836 + htab->sgot->output_offset + off - g_o_t;
2837 if ((r_type == R_386_TLS_IE || r_type == R_386_TLS_GOTIE)
2838 && tls_type == GOT_TLS_IE_BOTH)
2839 relocation += 4;
2840 if (r_type == R_386_TLS_IE)
2841 relocation += g_o_t;
2842 unresolved_reloc = FALSE;
2843 }
2844 else
2845 {
2846 unsigned int val, type;
2847 bfd_vma roff;
2848
2849 /* GD->IE transition. */
2850 BFD_ASSERT (rel->r_offset >= 2);
2851 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2852 BFD_ASSERT (type == 0x8d || type == 0x04);
2853 BFD_ASSERT (rel->r_offset + 9 <= input_section->size);
2854 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2855 == 0xe8);
2856 BFD_ASSERT (rel + 1 < relend);
2857 BFD_ASSERT (ELF32_R_TYPE (rel[1].r_info) == R_386_PLT32);
2858 roff = rel->r_offset - 3;
2859 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2860 if (type == 0x04)
2861 {
2862 /* leal foo(,%reg,1), %eax; call ___tls_get_addr
2863 Change it into:
2864 movl %gs:0, %eax; subl $foo@gottpoff(%reg), %eax. */
2865 BFD_ASSERT (rel->r_offset >= 3);
2866 BFD_ASSERT (bfd_get_8 (input_bfd,
2867 contents + rel->r_offset - 3)
2868 == 0x8d);
2869 BFD_ASSERT ((val & 0xc7) == 0x05 && val != (4 << 3));
2870 val >>= 3;
2871 }
2872 else
2873 {
2874 /* leal foo(%reg), %eax; call ___tls_get_addr; nop
2875 Change it into:
2876 movl %gs:0, %eax; subl $foo@gottpoff(%reg), %eax. */
2877 BFD_ASSERT (rel->r_offset + 10 <= input_section->size);
2878 BFD_ASSERT ((val & 0xf8) == 0x80 && (val & 7) != 4);
2879 BFD_ASSERT (bfd_get_8 (input_bfd,
2880 contents + rel->r_offset + 9)
2881 == 0x90);
2882 roff = rel->r_offset - 2;
2883 }
2884 memcpy (contents + roff,
2885 "\x65\xa1\0\0\0\0\x2b\x80\0\0\0", 12);
2886 contents[roff + 7] = 0x80 | (val & 7);
2887 /* If foo is used only with foo@gotntpoff(%reg) and
2888 foo@indntpoff, but not with foo@gottpoff(%reg), change
2889 subl $foo@gottpoff(%reg), %eax
2890 into:
2891 addl $foo@gotntpoff(%reg), %eax. */
2892 if (r_type == R_386_TLS_GOTIE)
2893 {
2894 contents[roff + 6] = 0x03;
2895 if (tls_type == GOT_TLS_IE_BOTH)
2896 off += 4;
2897 }
2898 bfd_put_32 (output_bfd,
2899 htab->sgot->output_section->vma
2900 + htab->sgot->output_offset + off
2901 - htab->sgotplt->output_section->vma
2902 - htab->sgotplt->output_offset,
2903 contents + roff + 8);
2904 /* Skip R_386_PLT32. */
2905 rel++;
2906 continue;
2907 }
2908 break;
2909
2910 case R_386_TLS_LDM:
2911 if (! info->shared)
2912 {
2913 unsigned int val;
2914
2915 /* LD->LE transition:
2916 Ensure it is:
2917 leal foo(%reg), %eax; call ___tls_get_addr.
2918 We change it into:
2919 movl %gs:0, %eax; nop; leal 0(%esi,1), %esi. */
2920 BFD_ASSERT (rel->r_offset >= 2);
2921 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 2)
2922 == 0x8d);
2923 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2924 BFD_ASSERT ((val & 0xf8) == 0x80 && (val & 7) != 4);
2925 BFD_ASSERT (rel->r_offset + 9 <= input_section->size);
2926 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2927 == 0xe8);
2928 BFD_ASSERT (rel + 1 < relend);
2929 BFD_ASSERT (ELF32_R_TYPE (rel[1].r_info) == R_386_PLT32);
2930 memcpy (contents + rel->r_offset - 2,
2931 "\x65\xa1\0\0\0\0\x90\x8d\x74\x26", 11);
2932 /* Skip R_386_PLT32. */
2933 rel++;
2934 continue;
2935 }
2936
2937 if (htab->sgot == NULL)
2938 abort ();
2939
2940 off = htab->tls_ldm_got.offset;
2941 if (off & 1)
2942 off &= ~1;
2943 else
2944 {
2945 Elf_Internal_Rela outrel;
2946 bfd_byte *loc;
2947
2948 if (htab->srelgot == NULL)
2949 abort ();
2950
2951 outrel.r_offset = (htab->sgot->output_section->vma
2952 + htab->sgot->output_offset + off);
2953
2954 bfd_put_32 (output_bfd, 0,
2955 htab->sgot->contents + off);
2956 bfd_put_32 (output_bfd, 0,
2957 htab->sgot->contents + off + 4);
2958 outrel.r_info = ELF32_R_INFO (0, R_386_TLS_DTPMOD32);
2959 loc = htab->srelgot->contents;
2960 loc += htab->srelgot->reloc_count++ * sizeof (Elf32_External_Rel);
2961 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2962 htab->tls_ldm_got.offset |= 1;
2963 }
2964 relocation = htab->sgot->output_section->vma
2965 + htab->sgot->output_offset + off
2966 - htab->sgotplt->output_section->vma
2967 - htab->sgotplt->output_offset;
2968 unresolved_reloc = FALSE;
2969 break;
2970
2971 case R_386_TLS_LDO_32:
2972 if (info->shared || (input_section->flags & SEC_CODE) == 0)
2973 relocation -= dtpoff_base (info);
2974 else
2975 /* When converting LDO to LE, we must negate. */
2976 relocation = -tpoff (info, relocation);
2977 break;
2978
2979 case R_386_TLS_LE_32:
2980 case R_386_TLS_LE:
2981 if (info->shared)
2982 {
2983 Elf_Internal_Rela outrel;
2984 asection *sreloc;
2985 bfd_byte *loc;
2986 int indx;
2987
2988 outrel.r_offset = rel->r_offset
2989 + input_section->output_section->vma
2990 + input_section->output_offset;
2991 if (h != NULL && h->dynindx != -1)
2992 indx = h->dynindx;
2993 else
2994 indx = 0;
2995 if (r_type == R_386_TLS_LE_32)
2996 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF32);
2997 else
2998 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF);
2999 sreloc = elf_section_data (input_section)->sreloc;
3000 if (sreloc == NULL)
3001 abort ();
3002 loc = sreloc->contents;
3003 loc += sreloc->reloc_count++ * sizeof (Elf32_External_Rel);
3004 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
3005 if (indx)
3006 continue;
3007 else if (r_type == R_386_TLS_LE_32)
3008 relocation = dtpoff_base (info) - relocation;
3009 else
3010 relocation -= dtpoff_base (info);
3011 }
3012 else if (r_type == R_386_TLS_LE_32)
3013 relocation = tpoff (info, relocation);
3014 else
3015 relocation = -tpoff (info, relocation);
3016 break;
3017
3018 default:
3019 break;
3020 }
3021
3022 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
3023 because such sections are not SEC_ALLOC and thus ld.so will
3024 not process them. */
3025 if (unresolved_reloc
3026 && !((input_section->flags & SEC_DEBUGGING) != 0
3027 && h->def_dynamic))
3028 {
3029 (*_bfd_error_handler)
3030 (_("%B(%A+0x%lx): unresolvable relocation against symbol `%s'"),
3031 input_bfd,
3032 input_section,
3033 (long) rel->r_offset,
3034 h->root.root.string);
3035 return FALSE;
3036 }
3037
3038 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
3039 contents, rel->r_offset,
3040 relocation, 0);
3041
3042 if (r != bfd_reloc_ok)
3043 {
3044 const char *name;
3045
3046 if (h != NULL)
3047 name = h->root.root.string;
3048 else
3049 {
3050 name = bfd_elf_string_from_elf_section (input_bfd,
3051 symtab_hdr->sh_link,
3052 sym->st_name);
3053 if (name == NULL)
3054 return FALSE;
3055 if (*name == '\0')
3056 name = bfd_section_name (input_bfd, sec);
3057 }
3058
3059 if (r == bfd_reloc_overflow)
3060 {
3061 if (! ((*info->callbacks->reloc_overflow)
3062 (info, (h ? &h->root : NULL), name, howto->name,
3063 (bfd_vma) 0, input_bfd, input_section,
3064 rel->r_offset)))
3065 return FALSE;
3066 }
3067 else
3068 {
3069 (*_bfd_error_handler)
3070 (_("%B(%A+0x%lx): reloc against `%s': error %d"),
3071 input_bfd, input_section,
3072 (long) rel->r_offset, name, (int) r);
3073 return FALSE;
3074 }
3075 }
3076 }
3077
3078 return TRUE;
3079 }
3080
3081 /* Finish up dynamic symbol handling. We set the contents of various
3082 dynamic sections here. */
3083
3084 static bfd_boolean
3085 elf_i386_finish_dynamic_symbol (bfd *output_bfd,
3086 struct bfd_link_info *info,
3087 struct elf_link_hash_entry *h,
3088 Elf_Internal_Sym *sym)
3089 {
3090 struct elf_i386_link_hash_table *htab;
3091
3092 htab = elf_i386_hash_table (info);
3093
3094 if (h->plt.offset != (bfd_vma) -1)
3095 {
3096 bfd_vma plt_index;
3097 bfd_vma got_offset;
3098 Elf_Internal_Rela rel;
3099 bfd_byte *loc;
3100
3101 /* This symbol has an entry in the procedure linkage table. Set
3102 it up. */
3103
3104 if (h->dynindx == -1
3105 || htab->splt == NULL
3106 || htab->sgotplt == NULL
3107 || htab->srelplt == NULL)
3108 abort ();
3109
3110 /* Get the index in the procedure linkage table which
3111 corresponds to this symbol. This is the index of this symbol
3112 in all the symbols for which we are making plt entries. The
3113 first entry in the procedure linkage table is reserved. */
3114 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
3115
3116 /* Get the offset into the .got table of the entry that
3117 corresponds to this function. Each .got entry is 4 bytes.
3118 The first three are reserved. */
3119 got_offset = (plt_index + 3) * 4;
3120
3121 /* Fill in the entry in the procedure linkage table. */
3122 if (! info->shared)
3123 {
3124 memcpy (htab->splt->contents + h->plt.offset, elf_i386_plt_entry,
3125 PLT_ENTRY_SIZE);
3126 bfd_put_32 (output_bfd,
3127 (htab->sgotplt->output_section->vma
3128 + htab->sgotplt->output_offset
3129 + got_offset),
3130 htab->splt->contents + h->plt.offset + 2);
3131
3132 if (htab->is_vxworks)
3133 {
3134 int s, k, reloc_index;
3135
3136 /* Create the R_386_32 relocation referencing the GOT
3137 for this PLT entry. */
3138
3139 /* S: Current slot number (zero-based). */
3140 s = (h->plt.offset - PLT_ENTRY_SIZE) / PLT_ENTRY_SIZE;
3141 /* K: Number of relocations for PLTResolve. */
3142 if (info->shared)
3143 k = PLTRESOLVE_RELOCS_SHLIB;
3144 else
3145 k = PLTRESOLVE_RELOCS;
3146 /* Skip the PLTresolve relocations, and the relocations for
3147 the other PLT slots. */
3148 reloc_index = k + s * PLT_NON_JUMP_SLOT_RELOCS;
3149 loc = (htab->srelplt2->contents + reloc_index
3150 * sizeof (Elf32_External_Rel));
3151
3152 rel.r_offset = (htab->splt->output_section->vma
3153 + htab->splt->output_offset
3154 + h->plt.offset + 2),
3155 rel.r_info = ELF32_R_INFO (htab->hgot->indx, R_386_32);
3156 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
3157
3158 /* Create the R_386_32 relocation referencing the beginning of
3159 the PLT for this GOT entry. */
3160 rel.r_offset = (htab->sgotplt->output_section->vma
3161 + htab->sgotplt->output_offset
3162 + got_offset);
3163 rel.r_info = ELF32_R_INFO (htab->hplt->indx, R_386_32);
3164 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3165 loc + sizeof (Elf32_External_Rel));
3166 }
3167 }
3168 else
3169 {
3170 memcpy (htab->splt->contents + h->plt.offset, elf_i386_pic_plt_entry,
3171 PLT_ENTRY_SIZE);
3172 bfd_put_32 (output_bfd, got_offset,
3173 htab->splt->contents + h->plt.offset + 2);
3174 }
3175
3176 bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel),
3177 htab->splt->contents + h->plt.offset + 7);
3178 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
3179 htab->splt->contents + h->plt.offset + 12);
3180
3181 /* Fill in the entry in the global offset table. */
3182 bfd_put_32 (output_bfd,
3183 (htab->splt->output_section->vma
3184 + htab->splt->output_offset
3185 + h->plt.offset
3186 + 6),
3187 htab->sgotplt->contents + got_offset);
3188
3189 /* Fill in the entry in the .rel.plt section. */
3190 rel.r_offset = (htab->sgotplt->output_section->vma
3191 + htab->sgotplt->output_offset
3192 + got_offset);
3193 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT);
3194 loc = htab->srelplt->contents + plt_index * sizeof (Elf32_External_Rel);
3195 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
3196
3197 if (!h->def_regular)
3198 {
3199 /* Mark the symbol as undefined, rather than as defined in
3200 the .plt section. Leave the value if there were any
3201 relocations where pointer equality matters (this is a clue
3202 for the dynamic linker, to make function pointer
3203 comparisons work between an application and shared
3204 library), otherwise set it to zero. If a function is only
3205 called from a binary, there is no need to slow down
3206 shared libraries because of that. */
3207 sym->st_shndx = SHN_UNDEF;
3208 if (!h->pointer_equality_needed)
3209 sym->st_value = 0;
3210 }
3211 }
3212
3213 if (h->got.offset != (bfd_vma) -1
3214 && elf_i386_hash_entry(h)->tls_type != GOT_TLS_GD
3215 && (elf_i386_hash_entry(h)->tls_type & GOT_TLS_IE) == 0)
3216 {
3217 Elf_Internal_Rela rel;
3218 bfd_byte *loc;
3219
3220 /* This symbol has an entry in the global offset table. Set it
3221 up. */
3222
3223 if (htab->sgot == NULL || htab->srelgot == NULL)
3224 abort ();
3225
3226 rel.r_offset = (htab->sgot->output_section->vma
3227 + htab->sgot->output_offset
3228 + (h->got.offset & ~(bfd_vma) 1));
3229
3230 /* If this is a static link, or it is a -Bsymbolic link and the
3231 symbol is defined locally or was forced to be local because
3232 of a version file, we just want to emit a RELATIVE reloc.
3233 The entry in the global offset table will already have been
3234 initialized in the relocate_section function. */
3235 if (info->shared
3236 && SYMBOL_REFERENCES_LOCAL (info, h))
3237 {
3238 BFD_ASSERT((h->got.offset & 1) != 0);
3239 rel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
3240 }
3241 else
3242 {
3243 BFD_ASSERT((h->got.offset & 1) == 0);
3244 bfd_put_32 (output_bfd, (bfd_vma) 0,
3245 htab->sgot->contents + h->got.offset);
3246 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_GLOB_DAT);
3247 }
3248
3249 loc = htab->srelgot->contents;
3250 loc += htab->srelgot->reloc_count++ * sizeof (Elf32_External_Rel);
3251 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
3252 }
3253
3254 if (h->needs_copy)
3255 {
3256 Elf_Internal_Rela rel;
3257 bfd_byte *loc;
3258
3259 /* This symbol needs a copy reloc. Set it up. */
3260
3261 if (h->dynindx == -1
3262 || (h->root.type != bfd_link_hash_defined
3263 && h->root.type != bfd_link_hash_defweak)
3264 || htab->srelbss == NULL)
3265 abort ();
3266
3267 rel.r_offset = (h->root.u.def.value
3268 + h->root.u.def.section->output_section->vma
3269 + h->root.u.def.section->output_offset);
3270 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_COPY);
3271 loc = htab->srelbss->contents;
3272 loc += htab->srelbss->reloc_count++ * sizeof (Elf32_External_Rel);
3273 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
3274 }
3275
3276 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute.
3277 On VxWorks, the _GLOBAL_OFFSET_TABLE_ symbol is not absolute: it
3278 is relative to the ".got" section. */
3279 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
3280 || (strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0
3281 && !htab->is_vxworks))
3282 sym->st_shndx = SHN_ABS;
3283
3284 return TRUE;
3285 }
3286
3287 /* Used to decide how to sort relocs in an optimal manner for the
3288 dynamic linker, before writing them out. */
3289
3290 static enum elf_reloc_type_class
3291 elf_i386_reloc_type_class (const Elf_Internal_Rela *rela)
3292 {
3293 switch (ELF32_R_TYPE (rela->r_info))
3294 {
3295 case R_386_RELATIVE:
3296 return reloc_class_relative;
3297 case R_386_JUMP_SLOT:
3298 return reloc_class_plt;
3299 case R_386_COPY:
3300 return reloc_class_copy;
3301 default:
3302 return reloc_class_normal;
3303 }
3304 }
3305
3306 /* Finish up the dynamic sections. */
3307
3308 static bfd_boolean
3309 elf_i386_finish_dynamic_sections (bfd *output_bfd,
3310 struct bfd_link_info *info)
3311 {
3312 struct elf_i386_link_hash_table *htab;
3313 bfd *dynobj;
3314 asection *sdyn;
3315
3316 htab = elf_i386_hash_table (info);
3317 dynobj = htab->elf.dynobj;
3318 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3319
3320 if (htab->elf.dynamic_sections_created)
3321 {
3322 Elf32_External_Dyn *dyncon, *dynconend;
3323
3324 if (sdyn == NULL || htab->sgot == NULL)
3325 abort ();
3326
3327 dyncon = (Elf32_External_Dyn *) sdyn->contents;
3328 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->size);
3329 for (; dyncon < dynconend; dyncon++)
3330 {
3331 Elf_Internal_Dyn dyn;
3332 asection *s;
3333
3334 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
3335
3336 switch (dyn.d_tag)
3337 {
3338 default:
3339 continue;
3340
3341 case DT_PLTGOT:
3342 s = htab->sgotplt;
3343 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
3344 break;
3345
3346 case DT_JMPREL:
3347 s = htab->srelplt;
3348 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
3349 break;
3350
3351 case DT_PLTRELSZ:
3352 s = htab->srelplt;
3353 dyn.d_un.d_val = s->size;
3354 break;
3355
3356 case DT_RELSZ:
3357 /* My reading of the SVR4 ABI indicates that the
3358 procedure linkage table relocs (DT_JMPREL) should be
3359 included in the overall relocs (DT_REL). This is
3360 what Solaris does. However, UnixWare can not handle
3361 that case. Therefore, we override the DT_RELSZ entry
3362 here to make it not include the JMPREL relocs. */
3363 s = htab->srelplt;
3364 if (s == NULL)
3365 continue;
3366 dyn.d_un.d_val -= s->size;
3367 break;
3368
3369 case DT_REL:
3370 /* We may not be using the standard ELF linker script.
3371 If .rel.plt is the first .rel section, we adjust
3372 DT_REL to not include it. */
3373 s = htab->srelplt;
3374 if (s == NULL)
3375 continue;
3376 if (dyn.d_un.d_ptr != s->output_section->vma + s->output_offset)
3377 continue;
3378 dyn.d_un.d_ptr += s->size;
3379 break;
3380 }
3381
3382 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3383 }
3384
3385 /* Fill in the first entry in the procedure linkage table. */
3386 if (htab->splt && htab->splt->size > 0)
3387 {
3388 if (info->shared)
3389 {
3390 memcpy (htab->splt->contents, elf_i386_pic_plt0_entry,
3391 sizeof (elf_i386_pic_plt0_entry));
3392 memset (htab->splt->contents + sizeof (elf_i386_pic_plt0_entry),
3393 htab->plt0_pad_byte,
3394 PLT_ENTRY_SIZE - sizeof (elf_i386_pic_plt0_entry));
3395 }
3396 else
3397 {
3398 memcpy (htab->splt->contents, elf_i386_plt0_entry,
3399 sizeof(elf_i386_plt0_entry));
3400 memset (htab->splt->contents + sizeof (elf_i386_plt0_entry),
3401 htab->plt0_pad_byte,
3402 PLT_ENTRY_SIZE - sizeof (elf_i386_plt0_entry));
3403 bfd_put_32 (output_bfd,
3404 (htab->sgotplt->output_section->vma
3405 + htab->sgotplt->output_offset
3406 + 4),
3407 htab->splt->contents + 2);
3408 bfd_put_32 (output_bfd,
3409 (htab->sgotplt->output_section->vma
3410 + htab->sgotplt->output_offset
3411 + 8),
3412 htab->splt->contents + 8);
3413
3414 if (htab->is_vxworks)
3415 {
3416 Elf_Internal_Rela rel;
3417 struct elf_link_hash_entry *hgot;
3418
3419 /* The VxWorks GOT is relocated by the dynamic linker.
3420 Therefore, we must emit relocations rather than
3421 simply computing the values now. */
3422 hgot = elf_link_hash_lookup (elf_hash_table (info),
3423 "_GLOBAL_OFFSET_TABLE_",
3424 FALSE, FALSE, FALSE);
3425 /* Generate a relocation for _GLOBAL_OFFSET_TABLE_ + 4.
3426 On IA32 we use REL relocations so the addend goes in
3427 the PLT directly. */
3428 rel.r_offset = (htab->splt->output_section->vma
3429 + htab->splt->output_offset
3430 + 2);
3431 rel.r_info = ELF32_R_INFO (hgot->indx, R_386_32);
3432 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3433 htab->srelplt2->contents);
3434 /* Generate a relocation for _GLOBAL_OFFSET_TABLE_ + 8. */
3435 rel.r_offset = (htab->splt->output_section->vma
3436 + htab->splt->output_offset
3437 + 8);
3438 rel.r_info = ELF32_R_INFO (hgot->indx, R_386_32);
3439 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3440 htab->srelplt2->contents +
3441 sizeof (Elf32_External_Rel));
3442 }
3443 }
3444
3445 /* UnixWare sets the entsize of .plt to 4, although that doesn't
3446 really seem like the right value. */
3447 elf_section_data (htab->splt->output_section)
3448 ->this_hdr.sh_entsize = 4;
3449
3450 /* Correct the .rel.plt.unloaded relocations. */
3451 if (htab->is_vxworks && !info->shared)
3452 {
3453 int num_plts = (htab->splt->size / PLT_ENTRY_SIZE) - 1;
3454 unsigned char *p;
3455
3456 p = htab->srelplt2->contents;
3457 if (info->shared)
3458 p += PLTRESOLVE_RELOCS_SHLIB * sizeof (Elf32_External_Rel);
3459 else
3460 p += PLTRESOLVE_RELOCS * sizeof (Elf32_External_Rel);
3461
3462 for (; num_plts; num_plts--)
3463 {
3464 Elf_Internal_Rela rel;
3465 bfd_elf32_swap_reloc_in (output_bfd, p, &rel);
3466 rel.r_info = ELF32_R_INFO (htab->hgot->indx, R_386_32);
3467 bfd_elf32_swap_reloc_out (output_bfd, &rel, p);
3468 p += sizeof (Elf32_External_Rel);
3469
3470 bfd_elf32_swap_reloc_in (output_bfd, p, &rel);
3471 rel.r_info = ELF32_R_INFO (htab->hplt->indx, R_386_32);
3472 bfd_elf32_swap_reloc_out (output_bfd, &rel, p);
3473 p += sizeof (Elf32_External_Rel);
3474 }
3475 }
3476 }
3477 }
3478
3479 if (htab->sgotplt)
3480 {
3481 /* Fill in the first three entries in the global offset table. */
3482 if (htab->sgotplt->size > 0)
3483 {
3484 bfd_put_32 (output_bfd,
3485 (sdyn == NULL ? 0
3486 : sdyn->output_section->vma + sdyn->output_offset),
3487 htab->sgotplt->contents);
3488 bfd_put_32 (output_bfd, 0, htab->sgotplt->contents + 4);
3489 bfd_put_32 (output_bfd, 0, htab->sgotplt->contents + 8);
3490 }
3491
3492 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize = 4;
3493 }
3494
3495 if (htab->sgot && htab->sgot->size > 0)
3496 elf_section_data (htab->sgot->output_section)->this_hdr.sh_entsize = 4;
3497
3498 return TRUE;
3499 }
3500
3501 /* Return address for Ith PLT stub in section PLT, for relocation REL
3502 or (bfd_vma) -1 if it should not be included. */
3503
3504 static bfd_vma
3505 elf_i386_plt_sym_val (bfd_vma i, const asection *plt,
3506 const arelent *rel ATTRIBUTE_UNUSED)
3507 {
3508 return plt->vma + (i + 1) * PLT_ENTRY_SIZE;
3509 }
3510
3511
3512 #define TARGET_LITTLE_SYM bfd_elf32_i386_vec
3513 #define TARGET_LITTLE_NAME "elf32-i386"
3514 #define ELF_ARCH bfd_arch_i386
3515 #define ELF_MACHINE_CODE EM_386
3516 #define ELF_MAXPAGESIZE 0x1000
3517
3518 #define elf_backend_can_gc_sections 1
3519 #define elf_backend_can_refcount 1
3520 #define elf_backend_want_got_plt 1
3521 #define elf_backend_plt_readonly 1
3522 #define elf_backend_want_plt_sym 0
3523 #define elf_backend_got_header_size 12
3524
3525 /* Support RELA for objdump of prelink objects. */
3526 #define elf_info_to_howto elf_i386_info_to_howto_rel
3527 #define elf_info_to_howto_rel elf_i386_info_to_howto_rel
3528
3529 #define bfd_elf32_mkobject elf_i386_mkobject
3530
3531 #define bfd_elf32_bfd_is_local_label_name elf_i386_is_local_label_name
3532 #define bfd_elf32_bfd_link_hash_table_create elf_i386_link_hash_table_create
3533 #define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup
3534
3535 #define elf_backend_adjust_dynamic_symbol elf_i386_adjust_dynamic_symbol
3536 #define elf_backend_check_relocs elf_i386_check_relocs
3537 #define elf_backend_copy_indirect_symbol elf_i386_copy_indirect_symbol
3538 #define elf_backend_create_dynamic_sections elf_i386_create_dynamic_sections
3539 #define elf_backend_fake_sections elf_i386_fake_sections
3540 #define elf_backend_finish_dynamic_sections elf_i386_finish_dynamic_sections
3541 #define elf_backend_finish_dynamic_symbol elf_i386_finish_dynamic_symbol
3542 #define elf_backend_gc_mark_hook elf_i386_gc_mark_hook
3543 #define elf_backend_gc_sweep_hook elf_i386_gc_sweep_hook
3544 #define elf_backend_grok_prstatus elf_i386_grok_prstatus
3545 #define elf_backend_grok_psinfo elf_i386_grok_psinfo
3546 #define elf_backend_reloc_type_class elf_i386_reloc_type_class
3547 #define elf_backend_relocate_section elf_i386_relocate_section
3548 #define elf_backend_size_dynamic_sections elf_i386_size_dynamic_sections
3549 #define elf_backend_plt_sym_val elf_i386_plt_sym_val
3550
3551 #include "elf32-target.h"
3552
3553 /* FreeBSD support. */
3554
3555 #undef TARGET_LITTLE_SYM
3556 #define TARGET_LITTLE_SYM bfd_elf32_i386_freebsd_vec
3557 #undef TARGET_LITTLE_NAME
3558 #define TARGET_LITTLE_NAME "elf32-i386-freebsd"
3559
3560 /* The kernel recognizes executables as valid only if they carry a
3561 "FreeBSD" label in the ELF header. So we put this label on all
3562 executables and (for simplicity) also all other object files. */
3563
3564 static void
3565 elf_i386_post_process_headers (bfd *abfd,
3566 struct bfd_link_info *info ATTRIBUTE_UNUSED)
3567 {
3568 Elf_Internal_Ehdr *i_ehdrp;
3569
3570 i_ehdrp = elf_elfheader (abfd);
3571
3572 /* Put an ABI label supported by FreeBSD >= 4.1. */
3573 i_ehdrp->e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
3574 #ifdef OLD_FREEBSD_ABI_LABEL
3575 /* The ABI label supported by FreeBSD <= 4.0 is quite nonstandard. */
3576 memcpy (&i_ehdrp->e_ident[EI_ABIVERSION], "FreeBSD", 8);
3577 #endif
3578 }
3579
3580 #undef elf_backend_post_process_headers
3581 #define elf_backend_post_process_headers elf_i386_post_process_headers
3582 #undef elf32_bed
3583 #define elf32_bed elf32_i386_fbsd_bed
3584
3585 #include "elf32-target.h"
3586
3587 /* VxWorks support. */
3588
3589 #undef TARGET_LITTLE_SYM
3590 #define TARGET_LITTLE_SYM bfd_elf32_i386_vxworks_vec
3591 #undef TARGET_LITTLE_NAME
3592 #define TARGET_LITTLE_NAME "elf32-i386-vxworks"
3593
3594
3595 /* Like elf_i386_link_hash_table_create but with tweaks for VxWorks. */
3596
3597 static struct bfd_link_hash_table *
3598 elf_i386_vxworks_link_hash_table_create (bfd *abfd)
3599 {
3600 struct bfd_link_hash_table *ret;
3601 struct elf_i386_link_hash_table *htab;
3602
3603 ret = elf_i386_link_hash_table_create (abfd);
3604 if (ret)
3605 {
3606 htab = (struct elf_i386_link_hash_table *) ret;
3607 htab->is_vxworks = 1;
3608 htab->plt0_pad_byte = 0x90;
3609 }
3610
3611 return ret;
3612 }
3613
3614
3615 /* Tweak magic VxWorks symbols as they are written to the output file. */
3616 static bfd_boolean
3617 elf_i386_vxworks_link_output_symbol_hook (struct bfd_link_info *info
3618 ATTRIBUTE_UNUSED,
3619 const char *name,
3620 Elf_Internal_Sym *sym,
3621 asection *input_sec ATTRIBUTE_UNUSED,
3622 struct elf_link_hash_entry *h
3623 ATTRIBUTE_UNUSED)
3624 {
3625 /* Ignore the first dummy symbol. */
3626 if (!name)
3627 return TRUE;
3628
3629 return elf_vxworks_link_output_symbol_hook (name, sym);
3630 }
3631
3632 #undef elf_backend_post_process_headers
3633 #undef bfd_elf32_bfd_link_hash_table_create
3634 #define bfd_elf32_bfd_link_hash_table_create \
3635 elf_i386_vxworks_link_hash_table_create
3636 #undef elf_backend_add_symbol_hook
3637 #define elf_backend_add_symbol_hook \
3638 elf_vxworks_add_symbol_hook
3639 #undef elf_backend_link_output_symbol_hook
3640 #define elf_backend_link_output_symbol_hook \
3641 elf_i386_vxworks_link_output_symbol_hook
3642 #undef elf_backend_emit_relocs
3643 #define elf_backend_emit_relocs elf_vxworks_emit_relocs
3644 #undef elf_backend_final_write_processing
3645 #define elf_backend_final_write_processing \
3646 elf_vxworks_final_write_processing
3647
3648 /* On VxWorks, we emit relocations against _PROCEDURE_LINKAGE_TABLE_, so
3649 define it. */
3650 #undef elf_backend_want_plt_sym
3651 #define elf_backend_want_plt_sym 1
3652
3653 #undef elf32_bed
3654 #define elf32_bed elf32_i386_vxworks_bed
3655
3656 #include "elf32-target.h"
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