Commit | Line | Data |
---|---|---|
65765700 | 1 | /* .eh_frame section optimization. |
64be1553 AM |
2 | Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007 |
3 | Free Software Foundation, Inc. | |
65765700 JJ |
4 | Written by Jakub Jelinek <jakub@redhat.com>. |
5 | ||
5ed6aba4 | 6 | This file is part of BFD, the Binary File Descriptor library. |
65765700 | 7 | |
5ed6aba4 NC |
8 | This program is free software; you can redistribute it and/or modify |
9 | it under the terms of the GNU General Public License as published by | |
cd123cb7 | 10 | the Free Software Foundation; either version 3 of the License, or |
5ed6aba4 | 11 | (at your option) any later version. |
65765700 | 12 | |
5ed6aba4 NC |
13 | This program is distributed in the hope that it will be useful, |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
65765700 | 17 | |
5ed6aba4 NC |
18 | You should have received a copy of the GNU General Public License |
19 | along with this program; if not, write to the Free Software | |
cd123cb7 NC |
20 | Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
21 | MA 02110-1301, USA. */ | |
65765700 | 22 | |
65765700 | 23 | #include "sysdep.h" |
3db64b00 | 24 | #include "bfd.h" |
65765700 JJ |
25 | #include "libbfd.h" |
26 | #include "elf-bfd.h" | |
27 | #include "elf/dwarf2.h" | |
28 | ||
29 | #define EH_FRAME_HDR_SIZE 8 | |
30 | ||
bce613b9 JJ |
31 | struct cie |
32 | { | |
33 | unsigned int length; | |
34 | unsigned int hash; | |
35 | unsigned char version; | |
f137a54e | 36 | unsigned char local_personality; |
bce613b9 JJ |
37 | char augmentation[20]; |
38 | bfd_vma code_align; | |
39 | bfd_signed_vma data_align; | |
40 | bfd_vma ra_column; | |
41 | bfd_vma augmentation_size; | |
f137a54e AM |
42 | union { |
43 | struct elf_link_hash_entry *h; | |
44 | bfd_vma val; | |
45 | } personality; | |
bce613b9 JJ |
46 | asection *output_sec; |
47 | struct eh_cie_fde *cie_inf; | |
48 | unsigned char per_encoding; | |
49 | unsigned char lsda_encoding; | |
50 | unsigned char fde_encoding; | |
51 | unsigned char initial_insn_length; | |
52 | unsigned char make_relative; | |
53 | unsigned char make_lsda_relative; | |
54 | unsigned char initial_instructions[50]; | |
55 | }; | |
56 | ||
57 | ||
58 | ||
2c42be65 RS |
59 | /* If *ITER hasn't reached END yet, read the next byte into *RESULT and |
60 | move onto the next byte. Return true on success. */ | |
61 | ||
62 | static inline bfd_boolean | |
63 | read_byte (bfd_byte **iter, bfd_byte *end, unsigned char *result) | |
64 | { | |
65 | if (*iter >= end) | |
66 | return FALSE; | |
67 | *result = *((*iter)++); | |
68 | return TRUE; | |
69 | } | |
70 | ||
71 | /* Move *ITER over LENGTH bytes, or up to END, whichever is closer. | |
72 | Return true it was possible to move LENGTH bytes. */ | |
73 | ||
74 | static inline bfd_boolean | |
75 | skip_bytes (bfd_byte **iter, bfd_byte *end, bfd_size_type length) | |
76 | { | |
77 | if ((bfd_size_type) (end - *iter) < length) | |
78 | { | |
79 | *iter = end; | |
80 | return FALSE; | |
81 | } | |
82 | *iter += length; | |
83 | return TRUE; | |
84 | } | |
85 | ||
86 | /* Move *ITER over an leb128, stopping at END. Return true if the end | |
87 | of the leb128 was found. */ | |
88 | ||
89 | static bfd_boolean | |
90 | skip_leb128 (bfd_byte **iter, bfd_byte *end) | |
91 | { | |
92 | unsigned char byte; | |
93 | do | |
94 | if (!read_byte (iter, end, &byte)) | |
95 | return FALSE; | |
96 | while (byte & 0x80); | |
97 | return TRUE; | |
98 | } | |
99 | ||
100 | /* Like skip_leb128, but treat the leb128 as an unsigned value and | |
101 | store it in *VALUE. */ | |
102 | ||
103 | static bfd_boolean | |
104 | read_uleb128 (bfd_byte **iter, bfd_byte *end, bfd_vma *value) | |
105 | { | |
106 | bfd_byte *start, *p; | |
107 | ||
108 | start = *iter; | |
109 | if (!skip_leb128 (iter, end)) | |
110 | return FALSE; | |
111 | ||
112 | p = *iter; | |
113 | *value = *--p; | |
114 | while (p > start) | |
115 | *value = (*value << 7) | (*--p & 0x7f); | |
116 | ||
117 | return TRUE; | |
118 | } | |
119 | ||
120 | /* Like read_uleb128, but for signed values. */ | |
121 | ||
122 | static bfd_boolean | |
123 | read_sleb128 (bfd_byte **iter, bfd_byte *end, bfd_signed_vma *value) | |
124 | { | |
125 | bfd_byte *start, *p; | |
126 | ||
127 | start = *iter; | |
128 | if (!skip_leb128 (iter, end)) | |
129 | return FALSE; | |
130 | ||
131 | p = *iter; | |
132 | *value = ((*--p & 0x7f) ^ 0x40) - 0x40; | |
133 | while (p > start) | |
134 | *value = (*value << 7) | (*--p & 0x7f); | |
135 | ||
136 | return TRUE; | |
137 | } | |
65765700 JJ |
138 | |
139 | /* Return 0 if either encoding is variable width, or not yet known to bfd. */ | |
140 | ||
141 | static | |
c39a58e6 | 142 | int get_DW_EH_PE_width (int encoding, int ptr_size) |
65765700 JJ |
143 | { |
144 | /* DW_EH_PE_ values of 0x60 and 0x70 weren't defined at the time .eh_frame | |
145 | was added to bfd. */ | |
146 | if ((encoding & 0x60) == 0x60) | |
147 | return 0; | |
148 | ||
149 | switch (encoding & 7) | |
150 | { | |
151 | case DW_EH_PE_udata2: return 2; | |
152 | case DW_EH_PE_udata4: return 4; | |
153 | case DW_EH_PE_udata8: return 8; | |
154 | case DW_EH_PE_absptr: return ptr_size; | |
155 | default: | |
156 | break; | |
157 | } | |
158 | ||
159 | return 0; | |
160 | } | |
161 | ||
84f97cb6 AS |
162 | #define get_DW_EH_PE_signed(encoding) (((encoding) & DW_EH_PE_signed) != 0) |
163 | ||
9e2a4898 JJ |
164 | /* Read a width sized value from memory. */ |
165 | ||
166 | static bfd_vma | |
c39a58e6 | 167 | read_value (bfd *abfd, bfd_byte *buf, int width, int is_signed) |
9e2a4898 JJ |
168 | { |
169 | bfd_vma value; | |
170 | ||
171 | switch (width) | |
172 | { | |
84f97cb6 AS |
173 | case 2: |
174 | if (is_signed) | |
175 | value = bfd_get_signed_16 (abfd, buf); | |
176 | else | |
177 | value = bfd_get_16 (abfd, buf); | |
178 | break; | |
179 | case 4: | |
180 | if (is_signed) | |
181 | value = bfd_get_signed_32 (abfd, buf); | |
182 | else | |
183 | value = bfd_get_32 (abfd, buf); | |
184 | break; | |
185 | case 8: | |
186 | if (is_signed) | |
187 | value = bfd_get_signed_64 (abfd, buf); | |
188 | else | |
189 | value = bfd_get_64 (abfd, buf); | |
190 | break; | |
191 | default: | |
192 | BFD_FAIL (); | |
193 | return 0; | |
9e2a4898 JJ |
194 | } |
195 | ||
196 | return value; | |
197 | } | |
b34976b6 | 198 | |
9e2a4898 JJ |
199 | /* Store a width sized value to memory. */ |
200 | ||
201 | static void | |
c39a58e6 | 202 | write_value (bfd *abfd, bfd_byte *buf, bfd_vma value, int width) |
9e2a4898 JJ |
203 | { |
204 | switch (width) | |
205 | { | |
206 | case 2: bfd_put_16 (abfd, value, buf); break; | |
207 | case 4: bfd_put_32 (abfd, value, buf); break; | |
208 | case 8: bfd_put_64 (abfd, value, buf); break; | |
209 | default: BFD_FAIL (); | |
210 | } | |
211 | } | |
212 | ||
bce613b9 | 213 | /* Return one if C1 and C2 CIEs can be merged. */ |
65765700 | 214 | |
bce613b9 JJ |
215 | static int |
216 | cie_eq (const void *e1, const void *e2) | |
65765700 | 217 | { |
bce613b9 JJ |
218 | const struct cie *c1 = e1; |
219 | const struct cie *c2 = e2; | |
220 | ||
221 | if (c1->hash == c2->hash | |
222 | && c1->length == c2->length | |
65765700 | 223 | && c1->version == c2->version |
f137a54e | 224 | && c1->local_personality == c2->local_personality |
65765700 JJ |
225 | && strcmp (c1->augmentation, c2->augmentation) == 0 |
226 | && strcmp (c1->augmentation, "eh") != 0 | |
227 | && c1->code_align == c2->code_align | |
228 | && c1->data_align == c2->data_align | |
229 | && c1->ra_column == c2->ra_column | |
230 | && c1->augmentation_size == c2->augmentation_size | |
f137a54e AM |
231 | && memcmp (&c1->personality, &c2->personality, |
232 | sizeof (c1->personality)) == 0 | |
bce613b9 | 233 | && c1->output_sec == c2->output_sec |
65765700 JJ |
234 | && c1->per_encoding == c2->per_encoding |
235 | && c1->lsda_encoding == c2->lsda_encoding | |
236 | && c1->fde_encoding == c2->fde_encoding | |
c39a58e6 | 237 | && c1->initial_insn_length == c2->initial_insn_length |
65765700 JJ |
238 | && memcmp (c1->initial_instructions, |
239 | c2->initial_instructions, | |
240 | c1->initial_insn_length) == 0) | |
bce613b9 | 241 | return 1; |
65765700 | 242 | |
bce613b9 JJ |
243 | return 0; |
244 | } | |
245 | ||
246 | static hashval_t | |
247 | cie_hash (const void *e) | |
248 | { | |
249 | const struct cie *c = e; | |
250 | return c->hash; | |
251 | } | |
252 | ||
253 | static hashval_t | |
254 | cie_compute_hash (struct cie *c) | |
255 | { | |
256 | hashval_t h = 0; | |
257 | h = iterative_hash_object (c->length, h); | |
258 | h = iterative_hash_object (c->version, h); | |
259 | h = iterative_hash (c->augmentation, strlen (c->augmentation) + 1, h); | |
260 | h = iterative_hash_object (c->code_align, h); | |
261 | h = iterative_hash_object (c->data_align, h); | |
262 | h = iterative_hash_object (c->ra_column, h); | |
263 | h = iterative_hash_object (c->augmentation_size, h); | |
264 | h = iterative_hash_object (c->personality, h); | |
265 | h = iterative_hash_object (c->output_sec, h); | |
266 | h = iterative_hash_object (c->per_encoding, h); | |
267 | h = iterative_hash_object (c->lsda_encoding, h); | |
268 | h = iterative_hash_object (c->fde_encoding, h); | |
269 | h = iterative_hash_object (c->initial_insn_length, h); | |
270 | h = iterative_hash (c->initial_instructions, c->initial_insn_length, h); | |
271 | c->hash = h; | |
272 | return h; | |
65765700 JJ |
273 | } |
274 | ||
353057a5 RS |
275 | /* Return the number of extra bytes that we'll be inserting into |
276 | ENTRY's augmentation string. */ | |
277 | ||
278 | static INLINE unsigned int | |
279 | extra_augmentation_string_bytes (struct eh_cie_fde *entry) | |
280 | { | |
281 | unsigned int size = 0; | |
282 | if (entry->cie) | |
283 | { | |
284 | if (entry->add_augmentation_size) | |
285 | size++; | |
286 | if (entry->add_fde_encoding) | |
287 | size++; | |
288 | } | |
289 | return size; | |
290 | } | |
291 | ||
292 | /* Likewise ENTRY's augmentation data. */ | |
293 | ||
294 | static INLINE unsigned int | |
295 | extra_augmentation_data_bytes (struct eh_cie_fde *entry) | |
296 | { | |
297 | unsigned int size = 0; | |
298 | if (entry->cie) | |
299 | { | |
300 | if (entry->add_augmentation_size) | |
301 | size++; | |
302 | if (entry->add_fde_encoding) | |
303 | size++; | |
304 | } | |
305 | else | |
306 | { | |
155eaaa0 | 307 | if (entry->u.fde.cie_inf->add_augmentation_size) |
353057a5 RS |
308 | size++; |
309 | } | |
310 | return size; | |
311 | } | |
312 | ||
313 | /* Return the size that ENTRY will have in the output. ALIGNMENT is the | |
314 | required alignment of ENTRY in bytes. */ | |
315 | ||
316 | static unsigned int | |
317 | size_of_output_cie_fde (struct eh_cie_fde *entry, unsigned int alignment) | |
318 | { | |
319 | if (entry->removed) | |
320 | return 0; | |
321 | if (entry->size == 4) | |
322 | return 4; | |
323 | return (entry->size | |
324 | + extra_augmentation_string_bytes (entry) | |
325 | + extra_augmentation_data_bytes (entry) | |
326 | + alignment - 1) & -alignment; | |
327 | } | |
328 | ||
dcf507a6 RS |
329 | /* Assume that the bytes between *ITER and END are CFA instructions. |
330 | Try to move *ITER past the first instruction and return true on | |
331 | success. ENCODED_PTR_WIDTH gives the width of pointer entries. */ | |
332 | ||
333 | static bfd_boolean | |
334 | skip_cfa_op (bfd_byte **iter, bfd_byte *end, unsigned int encoded_ptr_width) | |
335 | { | |
336 | bfd_byte op; | |
337 | bfd_vma length; | |
338 | ||
339 | if (!read_byte (iter, end, &op)) | |
340 | return FALSE; | |
341 | ||
ac685e6a | 342 | switch (op & 0xc0 ? op & 0xc0 : op) |
dcf507a6 RS |
343 | { |
344 | case DW_CFA_nop: | |
345 | case DW_CFA_advance_loc: | |
346 | case DW_CFA_restore: | |
ac685e6a JJ |
347 | case DW_CFA_remember_state: |
348 | case DW_CFA_restore_state: | |
349 | case DW_CFA_GNU_window_save: | |
dcf507a6 RS |
350 | /* No arguments. */ |
351 | return TRUE; | |
352 | ||
353 | case DW_CFA_offset: | |
354 | case DW_CFA_restore_extended: | |
355 | case DW_CFA_undefined: | |
356 | case DW_CFA_same_value: | |
357 | case DW_CFA_def_cfa_register: | |
358 | case DW_CFA_def_cfa_offset: | |
359 | case DW_CFA_def_cfa_offset_sf: | |
360 | case DW_CFA_GNU_args_size: | |
361 | /* One leb128 argument. */ | |
362 | return skip_leb128 (iter, end); | |
363 | ||
ac685e6a JJ |
364 | case DW_CFA_val_offset: |
365 | case DW_CFA_val_offset_sf: | |
dcf507a6 RS |
366 | case DW_CFA_offset_extended: |
367 | case DW_CFA_register: | |
368 | case DW_CFA_def_cfa: | |
369 | case DW_CFA_offset_extended_sf: | |
370 | case DW_CFA_GNU_negative_offset_extended: | |
371 | case DW_CFA_def_cfa_sf: | |
372 | /* Two leb128 arguments. */ | |
373 | return (skip_leb128 (iter, end) | |
374 | && skip_leb128 (iter, end)); | |
375 | ||
376 | case DW_CFA_def_cfa_expression: | |
377 | /* A variable-length argument. */ | |
378 | return (read_uleb128 (iter, end, &length) | |
379 | && skip_bytes (iter, end, length)); | |
380 | ||
381 | case DW_CFA_expression: | |
ac685e6a | 382 | case DW_CFA_val_expression: |
dcf507a6 RS |
383 | /* A leb128 followed by a variable-length argument. */ |
384 | return (skip_leb128 (iter, end) | |
385 | && read_uleb128 (iter, end, &length) | |
386 | && skip_bytes (iter, end, length)); | |
387 | ||
388 | case DW_CFA_set_loc: | |
389 | return skip_bytes (iter, end, encoded_ptr_width); | |
390 | ||
391 | case DW_CFA_advance_loc1: | |
392 | return skip_bytes (iter, end, 1); | |
393 | ||
394 | case DW_CFA_advance_loc2: | |
395 | return skip_bytes (iter, end, 2); | |
396 | ||
397 | case DW_CFA_advance_loc4: | |
398 | return skip_bytes (iter, end, 4); | |
399 | ||
400 | case DW_CFA_MIPS_advance_loc8: | |
401 | return skip_bytes (iter, end, 8); | |
402 | ||
403 | default: | |
404 | return FALSE; | |
405 | } | |
406 | } | |
407 | ||
408 | /* Try to interpret the bytes between BUF and END as CFA instructions. | |
409 | If every byte makes sense, return a pointer to the first DW_CFA_nop | |
410 | padding byte, or END if there is no padding. Return null otherwise. | |
411 | ENCODED_PTR_WIDTH is as for skip_cfa_op. */ | |
412 | ||
413 | static bfd_byte * | |
ac685e6a JJ |
414 | skip_non_nops (bfd_byte *buf, bfd_byte *end, unsigned int encoded_ptr_width, |
415 | unsigned int *set_loc_count) | |
dcf507a6 RS |
416 | { |
417 | bfd_byte *last; | |
418 | ||
419 | last = buf; | |
420 | while (buf < end) | |
421 | if (*buf == DW_CFA_nop) | |
422 | buf++; | |
423 | else | |
424 | { | |
ac685e6a JJ |
425 | if (*buf == DW_CFA_set_loc) |
426 | ++*set_loc_count; | |
dcf507a6 RS |
427 | if (!skip_cfa_op (&buf, end, encoded_ptr_width)) |
428 | return 0; | |
429 | last = buf; | |
430 | } | |
431 | return last; | |
432 | } | |
433 | ||
65765700 JJ |
434 | /* This function is called for each input file before the .eh_frame |
435 | section is relocated. It discards duplicate CIEs and FDEs for discarded | |
b34976b6 | 436 | functions. The function returns TRUE iff any entries have been |
65765700 JJ |
437 | deleted. */ |
438 | ||
b34976b6 | 439 | bfd_boolean |
c39a58e6 AM |
440 | _bfd_elf_discard_section_eh_frame |
441 | (bfd *abfd, struct bfd_link_info *info, asection *sec, | |
442 | bfd_boolean (*reloc_symbol_deleted_p) (bfd_vma, void *), | |
443 | struct elf_reloc_cookie *cookie) | |
65765700 | 444 | { |
acfe5567 RS |
445 | #define REQUIRE(COND) \ |
446 | do \ | |
447 | if (!(COND)) \ | |
448 | goto free_no_table; \ | |
449 | while (0) | |
450 | ||
65765700 | 451 | bfd_byte *ehbuf = NULL, *buf; |
bce613b9 JJ |
452 | bfd_byte *last_fde; |
453 | struct eh_cie_fde *ent, *this_inf; | |
454 | unsigned int hdr_length, hdr_id; | |
455 | struct extended_cie | |
456 | { | |
457 | struct cie cie; | |
458 | unsigned int offset; | |
459 | unsigned int usage_count; | |
460 | unsigned int entry; | |
461 | } *ecies = NULL, *ecie; | |
462 | unsigned int ecie_count = 0, ecie_alloced = 0; | |
463 | struct cie *cie; | |
126495ed | 464 | struct elf_link_hash_table *htab; |
65765700 | 465 | struct eh_frame_hdr_info *hdr_info; |
68f69152 | 466 | struct eh_frame_sec_info *sec_info = NULL; |
bce613b9 | 467 | unsigned int offset; |
65765700 | 468 | unsigned int ptr_size; |
bce613b9 | 469 | unsigned int entry_alloced; |
65765700 | 470 | |
eea6121a | 471 | if (sec->size == 0) |
65765700 JJ |
472 | { |
473 | /* This file does not contain .eh_frame information. */ | |
b34976b6 | 474 | return FALSE; |
65765700 JJ |
475 | } |
476 | ||
e460dd0d | 477 | if (bfd_is_abs_section (sec->output_section)) |
65765700 JJ |
478 | { |
479 | /* At least one of the sections is being discarded from the | |
3472e2e9 | 480 | link, so we should just ignore them. */ |
b34976b6 | 481 | return FALSE; |
65765700 JJ |
482 | } |
483 | ||
126495ed AM |
484 | htab = elf_hash_table (info); |
485 | hdr_info = &htab->eh_info; | |
68f69152 | 486 | |
bce613b9 JJ |
487 | if (hdr_info->cies == NULL && !info->relocatable) |
488 | hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free); | |
489 | ||
65765700 JJ |
490 | /* Read the frame unwind information from abfd. */ |
491 | ||
acfe5567 | 492 | REQUIRE (bfd_malloc_and_get_section (abfd, sec, &ehbuf)); |
68f69152 | 493 | |
eea6121a | 494 | if (sec->size >= 4 |
65765700 JJ |
495 | && bfd_get_32 (abfd, ehbuf) == 0 |
496 | && cookie->rel == cookie->relend) | |
497 | { | |
498 | /* Empty .eh_frame section. */ | |
499 | free (ehbuf); | |
b34976b6 | 500 | return FALSE; |
65765700 JJ |
501 | } |
502 | ||
65765700 JJ |
503 | /* If .eh_frame section size doesn't fit into int, we cannot handle |
504 | it (it would need to use 64-bit .eh_frame format anyway). */ | |
acfe5567 | 505 | REQUIRE (sec->size == (unsigned int) sec->size); |
65765700 | 506 | |
8c946ed5 RS |
507 | ptr_size = (get_elf_backend_data (abfd) |
508 | ->elf_backend_eh_frame_address_size (abfd, sec)); | |
509 | REQUIRE (ptr_size != 0); | |
510 | ||
65765700 | 511 | buf = ehbuf; |
65765700 JJ |
512 | sec_info = bfd_zmalloc (sizeof (struct eh_frame_sec_info) |
513 | + 99 * sizeof (struct eh_cie_fde)); | |
acfe5567 | 514 | REQUIRE (sec_info); |
eea6121a | 515 | |
bce613b9 | 516 | entry_alloced = 100; |
65765700 JJ |
517 | |
518 | #define ENSURE_NO_RELOCS(buf) \ | |
acfe5567 RS |
519 | REQUIRE (!(cookie->rel < cookie->relend \ |
520 | && (cookie->rel->r_offset \ | |
521 | < (bfd_size_type) ((buf) - ehbuf)) \ | |
522 | && cookie->rel->r_info != 0)) | |
65765700 JJ |
523 | |
524 | #define SKIP_RELOCS(buf) \ | |
525 | while (cookie->rel < cookie->relend \ | |
3472e2e9 | 526 | && (cookie->rel->r_offset \ |
65765700 JJ |
527 | < (bfd_size_type) ((buf) - ehbuf))) \ |
528 | cookie->rel++ | |
529 | ||
530 | #define GET_RELOC(buf) \ | |
531 | ((cookie->rel < cookie->relend \ | |
532 | && (cookie->rel->r_offset \ | |
3472e2e9 | 533 | == (bfd_size_type) ((buf) - ehbuf))) \ |
65765700 JJ |
534 | ? cookie->rel : NULL) |
535 | ||
536 | for (;;) | |
537 | { | |
f075ee0c | 538 | char *aug; |
ac685e6a | 539 | bfd_byte *start, *end, *insns, *insns_end; |
2c42be65 | 540 | bfd_size_type length; |
ac685e6a | 541 | unsigned int set_loc_count; |
65765700 | 542 | |
bce613b9 | 543 | if (sec_info->count == entry_alloced) |
65765700 JJ |
544 | { |
545 | sec_info = bfd_realloc (sec_info, | |
546 | sizeof (struct eh_frame_sec_info) | |
bce613b9 | 547 | + ((entry_alloced + 99) |
fda3ecf2 | 548 | * sizeof (struct eh_cie_fde))); |
acfe5567 | 549 | REQUIRE (sec_info); |
65765700 | 550 | |
bce613b9 | 551 | memset (&sec_info->entry[entry_alloced], 0, |
65765700 | 552 | 100 * sizeof (struct eh_cie_fde)); |
bce613b9 | 553 | entry_alloced += 100; |
65765700 JJ |
554 | } |
555 | ||
fda3ecf2 | 556 | this_inf = sec_info->entry + sec_info->count; |
65765700 | 557 | last_fde = buf; |
bce613b9 | 558 | |
eea6121a | 559 | if ((bfd_size_type) (buf - ehbuf) == sec->size) |
bce613b9 | 560 | break; |
acfe5567 | 561 | |
bce613b9 JJ |
562 | /* Read the length of the entry. */ |
563 | REQUIRE (skip_bytes (&buf, ehbuf + sec->size, 4)); | |
564 | hdr_length = bfd_get_32 (abfd, buf - 4); | |
acfe5567 | 565 | |
bce613b9 JJ |
566 | /* 64-bit .eh_frame is not supported. */ |
567 | REQUIRE (hdr_length != 0xffffffff); | |
65765700 | 568 | |
bce613b9 JJ |
569 | /* The CIE/FDE must be fully contained in this input section. */ |
570 | REQUIRE ((bfd_size_type) (buf - ehbuf) + hdr_length <= sec->size); | |
571 | end = buf + hdr_length; | |
65765700 | 572 | |
bce613b9 JJ |
573 | this_inf->offset = last_fde - ehbuf; |
574 | this_inf->size = 4 + hdr_length; | |
155eaaa0 | 575 | this_inf->reloc_index = cookie->rel - cookie->rels; |
bce613b9 JJ |
576 | |
577 | if (hdr_length == 0) | |
578 | { | |
579 | /* A zero-length CIE should only be found at the end of | |
580 | the section. */ | |
581 | REQUIRE ((bfd_size_type) (buf - ehbuf) == sec->size); | |
582 | ENSURE_NO_RELOCS (buf); | |
583 | sec_info->count++; | |
584 | break; | |
65765700 JJ |
585 | } |
586 | ||
bce613b9 JJ |
587 | REQUIRE (skip_bytes (&buf, end, 4)); |
588 | hdr_id = bfd_get_32 (abfd, buf - 4); | |
589 | ||
590 | if (hdr_id == 0) | |
65765700 JJ |
591 | { |
592 | unsigned int initial_insn_length; | |
593 | ||
594 | /* CIE */ | |
bce613b9 JJ |
595 | this_inf->cie = 1; |
596 | ||
597 | if (ecie_count == ecie_alloced) | |
65765700 | 598 | { |
bce613b9 JJ |
599 | ecies = bfd_realloc (ecies, |
600 | (ecie_alloced + 20) * sizeof (*ecies)); | |
601 | REQUIRE (ecies); | |
602 | memset (&ecies[ecie_alloced], 0, 20 * sizeof (*ecies)); | |
603 | ecie_alloced += 20; | |
65765700 JJ |
604 | } |
605 | ||
bce613b9 JJ |
606 | cie = &ecies[ecie_count].cie; |
607 | ecies[ecie_count].offset = this_inf->offset; | |
608 | ecies[ecie_count++].entry = sec_info->count; | |
609 | cie->length = hdr_length; | |
ac685e6a | 610 | start = buf; |
bce613b9 | 611 | REQUIRE (read_byte (&buf, end, &cie->version)); |
65765700 JJ |
612 | |
613 | /* Cannot handle unknown versions. */ | |
bce613b9 JJ |
614 | REQUIRE (cie->version == 1 || cie->version == 3); |
615 | REQUIRE (strlen ((char *) buf) < sizeof (cie->augmentation)); | |
65765700 | 616 | |
bce613b9 | 617 | strcpy (cie->augmentation, (char *) buf); |
f075ee0c | 618 | buf = (bfd_byte *) strchr ((char *) buf, '\0') + 1; |
65765700 JJ |
619 | ENSURE_NO_RELOCS (buf); |
620 | if (buf[0] == 'e' && buf[1] == 'h') | |
621 | { | |
622 | /* GCC < 3.0 .eh_frame CIE */ | |
623 | /* We cannot merge "eh" CIEs because __EXCEPTION_TABLE__ | |
624 | is private to each CIE, so we don't need it for anything. | |
625 | Just skip it. */ | |
2c42be65 | 626 | REQUIRE (skip_bytes (&buf, end, ptr_size)); |
65765700 JJ |
627 | SKIP_RELOCS (buf); |
628 | } | |
bce613b9 JJ |
629 | REQUIRE (read_uleb128 (&buf, end, &cie->code_align)); |
630 | REQUIRE (read_sleb128 (&buf, end, &cie->data_align)); | |
631 | if (cie->version == 1) | |
2c42be65 RS |
632 | { |
633 | REQUIRE (buf < end); | |
bce613b9 | 634 | cie->ra_column = *buf++; |
2c42be65 | 635 | } |
0da76f83 | 636 | else |
bce613b9 | 637 | REQUIRE (read_uleb128 (&buf, end, &cie->ra_column)); |
65765700 | 638 | ENSURE_NO_RELOCS (buf); |
bce613b9 JJ |
639 | cie->lsda_encoding = DW_EH_PE_omit; |
640 | cie->fde_encoding = DW_EH_PE_omit; | |
641 | cie->per_encoding = DW_EH_PE_omit; | |
642 | aug = cie->augmentation; | |
65765700 JJ |
643 | if (aug[0] != 'e' || aug[1] != 'h') |
644 | { | |
645 | if (*aug == 'z') | |
646 | { | |
647 | aug++; | |
bce613b9 | 648 | REQUIRE (read_uleb128 (&buf, end, &cie->augmentation_size)); |
65765700 JJ |
649 | ENSURE_NO_RELOCS (buf); |
650 | } | |
651 | ||
652 | while (*aug != '\0') | |
653 | switch (*aug++) | |
654 | { | |
655 | case 'L': | |
bce613b9 | 656 | REQUIRE (read_byte (&buf, end, &cie->lsda_encoding)); |
65765700 | 657 | ENSURE_NO_RELOCS (buf); |
bce613b9 | 658 | REQUIRE (get_DW_EH_PE_width (cie->lsda_encoding, ptr_size)); |
65765700 JJ |
659 | break; |
660 | case 'R': | |
bce613b9 | 661 | REQUIRE (read_byte (&buf, end, &cie->fde_encoding)); |
65765700 | 662 | ENSURE_NO_RELOCS (buf); |
bce613b9 | 663 | REQUIRE (get_DW_EH_PE_width (cie->fde_encoding, ptr_size)); |
65765700 | 664 | break; |
63752a75 JJ |
665 | case 'S': |
666 | break; | |
65765700 JJ |
667 | case 'P': |
668 | { | |
669 | int per_width; | |
670 | ||
bce613b9 JJ |
671 | REQUIRE (read_byte (&buf, end, &cie->per_encoding)); |
672 | per_width = get_DW_EH_PE_width (cie->per_encoding, | |
65765700 | 673 | ptr_size); |
acfe5567 | 674 | REQUIRE (per_width); |
bce613b9 | 675 | if ((cie->per_encoding & 0xf0) == DW_EH_PE_aligned) |
2c42be65 RS |
676 | { |
677 | length = -(buf - ehbuf) & (per_width - 1); | |
678 | REQUIRE (skip_bytes (&buf, end, length)); | |
679 | } | |
65765700 | 680 | ENSURE_NO_RELOCS (buf); |
f137a54e | 681 | /* Ensure we have a reloc here. */ |
99eb2ac8 | 682 | if (GET_RELOC (buf) != NULL) |
65765700 JJ |
683 | { |
684 | unsigned long r_symndx; | |
685 | ||
686 | #ifdef BFD64 | |
888cab37 RS |
687 | if (elf_elfheader (abfd)->e_ident[EI_CLASS] |
688 | == ELFCLASS64) | |
65765700 JJ |
689 | r_symndx = ELF64_R_SYM (cookie->rel->r_info); |
690 | else | |
691 | #endif | |
692 | r_symndx = ELF32_R_SYM (cookie->rel->r_info); | |
f137a54e AM |
693 | if (r_symndx >= cookie->locsymcount |
694 | || ELF_ST_BIND (cookie->locsyms[r_symndx] | |
695 | .st_info) != STB_LOCAL) | |
65765700 JJ |
696 | { |
697 | struct elf_link_hash_entry *h; | |
698 | ||
699 | r_symndx -= cookie->extsymoff; | |
700 | h = cookie->sym_hashes[r_symndx]; | |
701 | ||
702 | while (h->root.type == bfd_link_hash_indirect | |
703 | || h->root.type == bfd_link_hash_warning) | |
704 | h = (struct elf_link_hash_entry *) | |
705 | h->root.u.i.link; | |
706 | ||
f137a54e | 707 | cie->personality.h = h; |
65765700 | 708 | } |
ef8c95ad AM |
709 | else |
710 | { | |
ef8c95ad | 711 | Elf_Internal_Sym *sym; |
f137a54e AM |
712 | asection *sym_sec; |
713 | bfd_vma val; | |
714 | ||
715 | sym = &cookie->locsyms[r_symndx]; | |
716 | sym_sec = (bfd_section_from_elf_index | |
717 | (abfd, sym->st_shndx)); | |
3e5484db | 718 | if (sym_sec != NULL) |
ef8c95ad | 719 | { |
3e5484db AM |
720 | if (sym_sec->kept_section != NULL) |
721 | sym_sec = sym_sec->kept_section; | |
722 | if (sym_sec->output_section != NULL) | |
723 | { | |
724 | val = (sym->st_value | |
725 | + sym_sec->output_offset | |
726 | + sym_sec->output_section->vma); | |
727 | cie->personality.val = val; | |
728 | cie->local_personality = 1; | |
729 | } | |
ef8c95ad AM |
730 | } |
731 | } | |
ef8c95ad | 732 | |
f4a6705c RS |
733 | /* Cope with MIPS-style composite relocations. */ |
734 | do | |
735 | cookie->rel++; | |
736 | while (GET_RELOC (buf) != NULL); | |
65765700 | 737 | } |
2c42be65 | 738 | REQUIRE (skip_bytes (&buf, end, per_width)); |
f137a54e | 739 | REQUIRE (cie->local_personality || cie->personality.h); |
65765700 JJ |
740 | } |
741 | break; | |
742 | default: | |
743 | /* Unrecognized augmentation. Better bail out. */ | |
744 | goto free_no_table; | |
745 | } | |
746 | } | |
747 | ||
748 | /* For shared libraries, try to get rid of as many RELATIVE relocs | |
0bb2d96a | 749 | as possible. */ |
3472e2e9 | 750 | if (info->shared |
ec3391e7 AO |
751 | && (get_elf_backend_data (abfd) |
752 | ->elf_backend_can_make_relative_eh_frame | |
353057a5 RS |
753 | (abfd, info, sec))) |
754 | { | |
bce613b9 JJ |
755 | if ((cie->fde_encoding & 0xf0) == DW_EH_PE_absptr) |
756 | cie->make_relative = 1; | |
353057a5 RS |
757 | /* If the CIE doesn't already have an 'R' entry, it's fairly |
758 | easy to add one, provided that there's no aligned data | |
759 | after the augmentation string. */ | |
bce613b9 JJ |
760 | else if (cie->fde_encoding == DW_EH_PE_omit |
761 | && (cie->per_encoding & 0xf0) != DW_EH_PE_aligned) | |
353057a5 | 762 | { |
bce613b9 | 763 | if (*cie->augmentation == 0) |
353057a5 RS |
764 | this_inf->add_augmentation_size = 1; |
765 | this_inf->add_fde_encoding = 1; | |
bce613b9 | 766 | cie->make_relative = 1; |
353057a5 RS |
767 | } |
768 | } | |
65765700 | 769 | |
0bb2d96a | 770 | if (info->shared |
ec3391e7 AO |
771 | && (get_elf_backend_data (abfd) |
772 | ->elf_backend_can_make_lsda_relative_eh_frame | |
773 | (abfd, info, sec)) | |
bce613b9 JJ |
774 | && (cie->lsda_encoding & 0xf0) == DW_EH_PE_absptr) |
775 | cie->make_lsda_relative = 1; | |
9e2a4898 | 776 | |
65765700 JJ |
777 | /* If FDE encoding was not specified, it defaults to |
778 | DW_EH_absptr. */ | |
bce613b9 JJ |
779 | if (cie->fde_encoding == DW_EH_PE_omit) |
780 | cie->fde_encoding = DW_EH_PE_absptr; | |
65765700 | 781 | |
dcf507a6 | 782 | initial_insn_length = end - buf; |
bce613b9 | 783 | if (initial_insn_length <= sizeof (cie->initial_instructions)) |
65765700 | 784 | { |
bce613b9 JJ |
785 | cie->initial_insn_length = initial_insn_length; |
786 | memcpy (cie->initial_instructions, buf, initial_insn_length); | |
65765700 | 787 | } |
dcf507a6 | 788 | insns = buf; |
65765700 JJ |
789 | buf += initial_insn_length; |
790 | ENSURE_NO_RELOCS (buf); | |
65765700 JJ |
791 | } |
792 | else | |
793 | { | |
bce613b9 JJ |
794 | /* Find the corresponding CIE. */ |
795 | unsigned int cie_offset = this_inf->offset + 4 - hdr_id; | |
796 | for (ecie = ecies; ecie < ecies + ecie_count; ++ecie) | |
797 | if (cie_offset == ecie->offset) | |
798 | break; | |
799 | ||
800 | /* Ensure this FDE references one of the CIEs in this input | |
801 | section. */ | |
802 | REQUIRE (ecie != ecies + ecie_count); | |
803 | cie = &ecie->cie; | |
65765700 JJ |
804 | |
805 | ENSURE_NO_RELOCS (buf); | |
acfe5567 | 806 | REQUIRE (GET_RELOC (buf)); |
fda3ecf2 | 807 | |
65765700 | 808 | if ((*reloc_symbol_deleted_p) (buf - ehbuf, cookie)) |
353057a5 RS |
809 | /* This is a FDE against a discarded section. It should |
810 | be deleted. */ | |
811 | this_inf->removed = 1; | |
65765700 JJ |
812 | else |
813 | { | |
0bb2d96a | 814 | if (info->shared |
bce613b9 JJ |
815 | && (((cie->fde_encoding & 0xf0) == DW_EH_PE_absptr |
816 | && cie->make_relative == 0) | |
817 | || (cie->fde_encoding & 0xf0) == DW_EH_PE_aligned)) | |
0bb2d96a | 818 | { |
73722af0 | 819 | /* If a shared library uses absolute pointers |
0bb2d96a JJ |
820 | which we cannot turn into PC relative, |
821 | don't create the binary search table, | |
822 | since it is affected by runtime relocations. */ | |
b34976b6 | 823 | hdr_info->table = FALSE; |
64be1553 AM |
824 | (*info->callbacks->einfo) |
825 | (_("%P: fde encoding in %B(%A) prevents .eh_frame_hdr" | |
826 | " table being created.\n"), abfd, sec); | |
0bb2d96a | 827 | } |
bce613b9 | 828 | ecie->usage_count++; |
65765700 | 829 | hdr_info->fde_count++; |
155eaaa0 | 830 | this_inf->u.fde.cie_inf = (void *) (ecie - ecies); |
65765700 | 831 | } |
bce613b9 | 832 | |
2c42be65 RS |
833 | /* Skip the initial location and address range. */ |
834 | start = buf; | |
bce613b9 | 835 | length = get_DW_EH_PE_width (cie->fde_encoding, ptr_size); |
2c42be65 RS |
836 | REQUIRE (skip_bytes (&buf, end, 2 * length)); |
837 | ||
838 | /* Skip the augmentation size, if present. */ | |
bce613b9 | 839 | if (cie->augmentation[0] == 'z') |
dcf507a6 RS |
840 | REQUIRE (read_uleb128 (&buf, end, &length)); |
841 | else | |
842 | length = 0; | |
2c42be65 RS |
843 | |
844 | /* Of the supported augmentation characters above, only 'L' | |
845 | adds augmentation data to the FDE. This code would need to | |
846 | be adjusted if any future augmentations do the same thing. */ | |
bce613b9 | 847 | if (cie->lsda_encoding != DW_EH_PE_omit) |
dcf507a6 RS |
848 | { |
849 | this_inf->lsda_offset = buf - start; | |
850 | /* If there's no 'z' augmentation, we don't know where the | |
851 | CFA insns begin. Assume no padding. */ | |
bce613b9 | 852 | if (cie->augmentation[0] != 'z') |
dcf507a6 RS |
853 | length = end - buf; |
854 | } | |
855 | ||
856 | /* Skip over the augmentation data. */ | |
857 | REQUIRE (skip_bytes (&buf, end, length)); | |
858 | insns = buf; | |
9e2a4898 | 859 | |
bce613b9 | 860 | buf = last_fde + 4 + hdr_length; |
65765700 JJ |
861 | SKIP_RELOCS (buf); |
862 | } | |
863 | ||
dcf507a6 RS |
864 | /* Try to interpret the CFA instructions and find the first |
865 | padding nop. Shrink this_inf's size so that it doesn't | |
ac685e6a | 866 | include the padding. */ |
bce613b9 | 867 | length = get_DW_EH_PE_width (cie->fde_encoding, ptr_size); |
ac685e6a JJ |
868 | set_loc_count = 0; |
869 | insns_end = skip_non_nops (insns, end, length, &set_loc_count); | |
870 | /* If we don't understand the CFA instructions, we can't know | |
871 | what needs to be adjusted there. */ | |
872 | if (insns_end == NULL | |
873 | /* For the time being we don't support DW_CFA_set_loc in | |
874 | CIE instructions. */ | |
875 | || (set_loc_count && this_inf->cie)) | |
876 | goto free_no_table; | |
877 | this_inf->size -= end - insns_end; | |
bce613b9 JJ |
878 | if (insns_end != end && this_inf->cie) |
879 | { | |
880 | cie->initial_insn_length -= end - insns_end; | |
881 | cie->length -= end - insns_end; | |
882 | } | |
ac685e6a | 883 | if (set_loc_count |
bce613b9 JJ |
884 | && ((cie->fde_encoding & 0xf0) == DW_EH_PE_pcrel |
885 | || cie->make_relative)) | |
ac685e6a JJ |
886 | { |
887 | unsigned int cnt; | |
888 | bfd_byte *p; | |
889 | ||
890 | this_inf->set_loc = bfd_malloc ((set_loc_count + 1) | |
891 | * sizeof (unsigned int)); | |
892 | REQUIRE (this_inf->set_loc); | |
893 | this_inf->set_loc[0] = set_loc_count; | |
894 | p = insns; | |
895 | cnt = 0; | |
896 | while (p < end) | |
897 | { | |
898 | if (*p == DW_CFA_set_loc) | |
899 | this_inf->set_loc[++cnt] = p + 1 - start; | |
900 | REQUIRE (skip_cfa_op (&p, end, length)); | |
901 | } | |
902 | } | |
dcf507a6 | 903 | |
bce613b9 JJ |
904 | this_inf->fde_encoding = cie->fde_encoding; |
905 | this_inf->lsda_encoding = cie->lsda_encoding; | |
65765700 JJ |
906 | sec_info->count++; |
907 | } | |
908 | ||
909 | elf_section_data (sec)->sec_info = sec_info; | |
68bfbfcc | 910 | sec->sec_info_type = ELF_INFO_TYPE_EH_FRAME; |
65765700 | 911 | |
bce613b9 JJ |
912 | /* Look at all CIEs in this section and determine which can be |
913 | removed as unused, which can be merged with previous duplicate | |
914 | CIEs and which need to be kept. */ | |
915 | for (ecie = ecies; ecie < ecies + ecie_count; ++ecie) | |
916 | { | |
917 | if (ecie->usage_count == 0) | |
918 | { | |
919 | sec_info->entry[ecie->entry].removed = 1; | |
920 | continue; | |
921 | } | |
922 | ecie->cie.output_sec = sec->output_section; | |
923 | ecie->cie.cie_inf = sec_info->entry + ecie->entry; | |
924 | cie_compute_hash (&ecie->cie); | |
925 | if (hdr_info->cies != NULL) | |
926 | { | |
927 | void **loc = htab_find_slot_with_hash (hdr_info->cies, &ecie->cie, | |
928 | ecie->cie.hash, INSERT); | |
929 | if (loc != NULL) | |
930 | { | |
931 | if (*loc != HTAB_EMPTY_ENTRY) | |
932 | { | |
933 | sec_info->entry[ecie->entry].removed = 1; | |
934 | ecie->cie.cie_inf = ((struct cie *) *loc)->cie_inf; | |
935 | continue; | |
936 | } | |
937 | ||
938 | *loc = malloc (sizeof (struct cie)); | |
939 | if (*loc == NULL) | |
940 | *loc = HTAB_DELETED_ENTRY; | |
941 | else | |
942 | memcpy (*loc, &ecie->cie, sizeof (struct cie)); | |
943 | } | |
944 | } | |
945 | ecie->cie.cie_inf->make_relative = ecie->cie.make_relative; | |
946 | ecie->cie.cie_inf->make_lsda_relative = ecie->cie.make_lsda_relative; | |
947 | ecie->cie.cie_inf->per_encoding_relative | |
948 | = (ecie->cie.per_encoding & 0x70) == DW_EH_PE_pcrel; | |
949 | } | |
950 | ||
65765700 JJ |
951 | /* Ok, now we can assign new offsets. */ |
952 | offset = 0; | |
fda3ecf2 AM |
953 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) |
954 | if (!ent->removed) | |
955 | { | |
bce613b9 JJ |
956 | if (!ent->cie) |
957 | { | |
155eaaa0 RS |
958 | ecie = ecies + (bfd_hostptr_t) ent->u.fde.cie_inf; |
959 | ent->u.fde.cie_inf = ecie->cie.cie_inf; | |
bce613b9 | 960 | } |
353057a5 RS |
961 | ent->new_offset = offset; |
962 | offset += size_of_output_cie_fde (ent, ptr_size); | |
fda3ecf2 | 963 | } |
65765700 | 964 | |
353057a5 | 965 | /* Resize the sec as needed. */ |
eea6121a | 966 | sec->rawsize = sec->size; |
353057a5 | 967 | sec->size = offset; |
65765700 | 968 | |
68f69152 | 969 | free (ehbuf); |
bce613b9 JJ |
970 | if (ecies) |
971 | free (ecies); | |
353057a5 | 972 | return offset != sec->rawsize; |
65765700 JJ |
973 | |
974 | free_no_table: | |
64be1553 AM |
975 | (*info->callbacks->einfo) |
976 | (_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"), | |
977 | abfd, sec); | |
68f69152 JJ |
978 | if (ehbuf) |
979 | free (ehbuf); | |
65765700 JJ |
980 | if (sec_info) |
981 | free (sec_info); | |
bce613b9 JJ |
982 | if (ecies) |
983 | free (ecies); | |
b34976b6 | 984 | hdr_info->table = FALSE; |
b34976b6 | 985 | return FALSE; |
acfe5567 RS |
986 | |
987 | #undef REQUIRE | |
65765700 JJ |
988 | } |
989 | ||
990 | /* This function is called for .eh_frame_hdr section after | |
991 | _bfd_elf_discard_section_eh_frame has been called on all .eh_frame | |
992 | input sections. It finalizes the size of .eh_frame_hdr section. */ | |
993 | ||
b34976b6 | 994 | bfd_boolean |
c39a58e6 | 995 | _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) |
65765700 | 996 | { |
126495ed | 997 | struct elf_link_hash_table *htab; |
65765700 | 998 | struct eh_frame_hdr_info *hdr_info; |
126495ed | 999 | asection *sec; |
65765700 | 1000 | |
126495ed AM |
1001 | htab = elf_hash_table (info); |
1002 | hdr_info = &htab->eh_info; | |
bce613b9 JJ |
1003 | |
1004 | if (hdr_info->cies != NULL) | |
1005 | { | |
1006 | htab_delete (hdr_info->cies); | |
1007 | hdr_info->cies = NULL; | |
1008 | } | |
1009 | ||
126495ed AM |
1010 | sec = hdr_info->hdr_sec; |
1011 | if (sec == NULL) | |
b34976b6 | 1012 | return FALSE; |
126495ed | 1013 | |
eea6121a | 1014 | sec->size = EH_FRAME_HDR_SIZE; |
65765700 | 1015 | if (hdr_info->table) |
eea6121a | 1016 | sec->size += 4 + hdr_info->fde_count * 8; |
65765700 | 1017 | |
126495ed | 1018 | elf_tdata (abfd)->eh_frame_hdr = sec; |
b34976b6 | 1019 | return TRUE; |
65765700 JJ |
1020 | } |
1021 | ||
68f69152 JJ |
1022 | /* This function is called from size_dynamic_sections. |
1023 | It needs to decide whether .eh_frame_hdr should be output or not, | |
8423293d AM |
1024 | because when the dynamic symbol table has been sized it is too late |
1025 | to strip sections. */ | |
68f69152 | 1026 | |
b34976b6 | 1027 | bfd_boolean |
c39a58e6 | 1028 | _bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info) |
68f69152 | 1029 | { |
126495ed | 1030 | asection *o; |
68f69152 | 1031 | bfd *abfd; |
126495ed | 1032 | struct elf_link_hash_table *htab; |
68f69152 JJ |
1033 | struct eh_frame_hdr_info *hdr_info; |
1034 | ||
126495ed AM |
1035 | htab = elf_hash_table (info); |
1036 | hdr_info = &htab->eh_info; | |
1037 | if (hdr_info->hdr_sec == NULL) | |
b34976b6 | 1038 | return TRUE; |
68f69152 | 1039 | |
126495ed AM |
1040 | if (bfd_is_abs_section (hdr_info->hdr_sec->output_section)) |
1041 | { | |
1042 | hdr_info->hdr_sec = NULL; | |
b34976b6 | 1043 | return TRUE; |
126495ed | 1044 | } |
68f69152 JJ |
1045 | |
1046 | abfd = NULL; | |
1047 | if (info->eh_frame_hdr) | |
1048 | for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next) | |
1049 | { | |
1050 | /* Count only sections which have at least a single CIE or FDE. | |
1051 | There cannot be any CIE or FDE <= 8 bytes. */ | |
1052 | o = bfd_get_section_by_name (abfd, ".eh_frame"); | |
eea6121a | 1053 | if (o && o->size > 8 && !bfd_is_abs_section (o->output_section)) |
68f69152 JJ |
1054 | break; |
1055 | } | |
1056 | ||
1057 | if (abfd == NULL) | |
1058 | { | |
8423293d | 1059 | hdr_info->hdr_sec->flags |= SEC_EXCLUDE; |
126495ed | 1060 | hdr_info->hdr_sec = NULL; |
b34976b6 | 1061 | return TRUE; |
68f69152 | 1062 | } |
126495ed | 1063 | |
b34976b6 AM |
1064 | hdr_info->table = TRUE; |
1065 | return TRUE; | |
68f69152 JJ |
1066 | } |
1067 | ||
65765700 JJ |
1068 | /* Adjust an address in the .eh_frame section. Given OFFSET within |
1069 | SEC, this returns the new offset in the adjusted .eh_frame section, | |
1070 | or -1 if the address refers to a CIE/FDE which has been removed | |
1071 | or to offset with dynamic relocation which is no longer needed. */ | |
1072 | ||
1073 | bfd_vma | |
c39a58e6 | 1074 | _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED, |
92e4ec35 | 1075 | struct bfd_link_info *info, |
c39a58e6 AM |
1076 | asection *sec, |
1077 | bfd_vma offset) | |
65765700 JJ |
1078 | { |
1079 | struct eh_frame_sec_info *sec_info; | |
92e4ec35 AM |
1080 | struct elf_link_hash_table *htab; |
1081 | struct eh_frame_hdr_info *hdr_info; | |
65765700 JJ |
1082 | unsigned int lo, hi, mid; |
1083 | ||
68bfbfcc | 1084 | if (sec->sec_info_type != ELF_INFO_TYPE_EH_FRAME) |
65765700 | 1085 | return offset; |
c39a58e6 | 1086 | sec_info = elf_section_data (sec)->sec_info; |
65765700 | 1087 | |
eea6121a AM |
1088 | if (offset >= sec->rawsize) |
1089 | return offset - sec->rawsize + sec->size; | |
65765700 | 1090 | |
92e4ec35 AM |
1091 | htab = elf_hash_table (info); |
1092 | hdr_info = &htab->eh_info; | |
1093 | if (hdr_info->offsets_adjusted) | |
1094 | offset += sec->output_offset; | |
1095 | ||
65765700 JJ |
1096 | lo = 0; |
1097 | hi = sec_info->count; | |
1098 | mid = 0; | |
1099 | while (lo < hi) | |
1100 | { | |
1101 | mid = (lo + hi) / 2; | |
1102 | if (offset < sec_info->entry[mid].offset) | |
1103 | hi = mid; | |
1104 | else if (offset | |
1105 | >= sec_info->entry[mid].offset + sec_info->entry[mid].size) | |
1106 | lo = mid + 1; | |
1107 | else | |
1108 | break; | |
1109 | } | |
1110 | ||
1111 | BFD_ASSERT (lo < hi); | |
1112 | ||
1113 | /* FDE or CIE was removed. */ | |
1114 | if (sec_info->entry[mid].removed) | |
1115 | return (bfd_vma) -1; | |
1116 | ||
1117 | /* If converting to DW_EH_PE_pcrel, there will be no need for run-time | |
1118 | relocation against FDE's initial_location field. */ | |
fda3ecf2 | 1119 | if (!sec_info->entry[mid].cie |
155eaaa0 | 1120 | && sec_info->entry[mid].u.fde.cie_inf->make_relative |
353057a5 RS |
1121 | && offset == sec_info->entry[mid].offset + 8) |
1122 | return (bfd_vma) -2; | |
65765700 | 1123 | |
9e2a4898 JJ |
1124 | /* If converting LSDA pointers to DW_EH_PE_pcrel, there will be no need |
1125 | for run-time relocation against LSDA field. */ | |
fda3ecf2 | 1126 | if (!sec_info->entry[mid].cie |
155eaaa0 | 1127 | && sec_info->entry[mid].u.fde.cie_inf->make_lsda_relative |
126495ed | 1128 | && (offset == (sec_info->entry[mid].offset + 8 |
92e4ec35 | 1129 | + sec_info->entry[mid].lsda_offset)) |
155eaaa0 | 1130 | && (sec_info->entry[mid].u.fde.cie_inf->need_lsda_relative |
92e4ec35 | 1131 | || !hdr_info->offsets_adjusted)) |
8935b81f | 1132 | { |
155eaaa0 | 1133 | sec_info->entry[mid].u.fde.cie_inf->need_lsda_relative = 1; |
8935b81f AM |
1134 | return (bfd_vma) -2; |
1135 | } | |
9e2a4898 | 1136 | |
ac685e6a JJ |
1137 | /* If converting to DW_EH_PE_pcrel, there will be no need for run-time |
1138 | relocation against DW_CFA_set_loc's arguments. */ | |
1139 | if (sec_info->entry[mid].set_loc | |
1140 | && (sec_info->entry[mid].cie | |
1141 | ? sec_info->entry[mid].make_relative | |
155eaaa0 | 1142 | : sec_info->entry[mid].u.fde.cie_inf->make_relative) |
ac685e6a JJ |
1143 | && (offset >= sec_info->entry[mid].offset + 8 |
1144 | + sec_info->entry[mid].set_loc[1])) | |
1145 | { | |
1146 | unsigned int cnt; | |
1147 | ||
1148 | for (cnt = 1; cnt <= sec_info->entry[mid].set_loc[0]; cnt++) | |
1149 | if (offset == sec_info->entry[mid].offset + 8 | |
1150 | + sec_info->entry[mid].set_loc[cnt]) | |
1151 | return (bfd_vma) -2; | |
1152 | } | |
1153 | ||
92e4ec35 AM |
1154 | if (hdr_info->offsets_adjusted) |
1155 | offset -= sec->output_offset; | |
353057a5 | 1156 | /* Any new augmentation bytes go before the first relocation. */ |
c68836a9 | 1157 | return (offset + sec_info->entry[mid].new_offset |
353057a5 RS |
1158 | - sec_info->entry[mid].offset |
1159 | + extra_augmentation_string_bytes (sec_info->entry + mid) | |
1160 | + extra_augmentation_data_bytes (sec_info->entry + mid)); | |
65765700 JJ |
1161 | } |
1162 | ||
1163 | /* Write out .eh_frame section. This is called with the relocated | |
1164 | contents. */ | |
1165 | ||
b34976b6 | 1166 | bfd_boolean |
c39a58e6 AM |
1167 | _bfd_elf_write_section_eh_frame (bfd *abfd, |
1168 | struct bfd_link_info *info, | |
1169 | asection *sec, | |
1170 | bfd_byte *contents) | |
65765700 JJ |
1171 | { |
1172 | struct eh_frame_sec_info *sec_info; | |
126495ed | 1173 | struct elf_link_hash_table *htab; |
65765700 | 1174 | struct eh_frame_hdr_info *hdr_info; |
65765700 | 1175 | unsigned int ptr_size; |
fda3ecf2 | 1176 | struct eh_cie_fde *ent; |
65765700 | 1177 | |
68bfbfcc | 1178 | if (sec->sec_info_type != ELF_INFO_TYPE_EH_FRAME) |
c39a58e6 | 1179 | return bfd_set_section_contents (abfd, sec->output_section, contents, |
eea6121a | 1180 | sec->output_offset, sec->size); |
8c946ed5 RS |
1181 | |
1182 | ptr_size = (get_elf_backend_data (abfd) | |
1183 | ->elf_backend_eh_frame_address_size (abfd, sec)); | |
1184 | BFD_ASSERT (ptr_size != 0); | |
1185 | ||
c39a58e6 | 1186 | sec_info = elf_section_data (sec)->sec_info; |
126495ed AM |
1187 | htab = elf_hash_table (info); |
1188 | hdr_info = &htab->eh_info; | |
3472e2e9 AM |
1189 | |
1190 | /* First convert all offsets to output section offsets, so that a | |
1191 | CIE offset is valid if the CIE is used by a FDE from some other | |
1192 | section. This can happen when duplicate CIEs are deleted in | |
1193 | _bfd_elf_discard_section_eh_frame. We do all sections here because | |
1194 | this function might not be called on sections in the same order as | |
1195 | _bfd_elf_discard_section_eh_frame. */ | |
1196 | if (!hdr_info->offsets_adjusted) | |
1197 | { | |
1198 | bfd *ibfd; | |
1199 | asection *eh; | |
1200 | struct eh_frame_sec_info *eh_inf; | |
1201 | ||
1202 | for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next) | |
1203 | { | |
1204 | if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour | |
1205 | || (ibfd->flags & DYNAMIC) != 0) | |
1206 | continue; | |
1207 | ||
1208 | eh = bfd_get_section_by_name (ibfd, ".eh_frame"); | |
1209 | if (eh == NULL || eh->sec_info_type != ELF_INFO_TYPE_EH_FRAME) | |
1210 | continue; | |
1211 | ||
1212 | eh_inf = elf_section_data (eh)->sec_info; | |
1213 | for (ent = eh_inf->entry; ent < eh_inf->entry + eh_inf->count; ++ent) | |
1214 | { | |
1215 | ent->offset += eh->output_offset; | |
1216 | ent->new_offset += eh->output_offset; | |
1217 | } | |
1218 | } | |
1219 | hdr_info->offsets_adjusted = TRUE; | |
1220 | } | |
1221 | ||
126495ed AM |
1222 | if (hdr_info->table && hdr_info->array == NULL) |
1223 | hdr_info->array | |
1224 | = bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array)); | |
1225 | if (hdr_info->array == NULL) | |
1226 | hdr_info = NULL; | |
65765700 | 1227 | |
353057a5 RS |
1228 | /* The new offsets can be bigger or smaller than the original offsets. |
1229 | We therefore need to make two passes over the section: one backward | |
1230 | pass to move entries up and one forward pass to move entries down. | |
1231 | The two passes won't interfere with each other because entries are | |
1232 | not reordered */ | |
1233 | for (ent = sec_info->entry + sec_info->count; ent-- != sec_info->entry;) | |
1234 | if (!ent->removed && ent->new_offset > ent->offset) | |
1235 | memmove (contents + ent->new_offset - sec->output_offset, | |
1236 | contents + ent->offset - sec->output_offset, ent->size); | |
1237 | ||
1238 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) | |
1239 | if (!ent->removed && ent->new_offset < ent->offset) | |
1240 | memmove (contents + ent->new_offset - sec->output_offset, | |
1241 | contents + ent->offset - sec->output_offset, ent->size); | |
1242 | ||
fda3ecf2 | 1243 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) |
65765700 | 1244 | { |
353057a5 RS |
1245 | unsigned char *buf, *end; |
1246 | unsigned int new_size; | |
1247 | ||
fda3ecf2 AM |
1248 | if (ent->removed) |
1249 | continue; | |
1250 | ||
353057a5 RS |
1251 | if (ent->size == 4) |
1252 | { | |
1253 | /* Any terminating FDE must be at the end of the section. */ | |
1254 | BFD_ASSERT (ent == sec_info->entry + sec_info->count - 1); | |
1255 | continue; | |
1256 | } | |
1257 | ||
1258 | buf = contents + ent->new_offset - sec->output_offset; | |
1259 | end = buf + ent->size; | |
1260 | new_size = size_of_output_cie_fde (ent, ptr_size); | |
1261 | ||
a34a056a L |
1262 | /* Update the size. It may be shrinked. */ |
1263 | bfd_put_32 (abfd, new_size - 4, buf); | |
1264 | ||
1265 | /* Filling the extra bytes with DW_CFA_nops. */ | |
353057a5 | 1266 | if (new_size != ent->size) |
a34a056a | 1267 | memset (end, 0, new_size - ent->size); |
353057a5 | 1268 | |
fda3ecf2 | 1269 | if (ent->cie) |
65765700 JJ |
1270 | { |
1271 | /* CIE */ | |
353057a5 | 1272 | if (ent->make_relative |
fda3ecf2 AM |
1273 | || ent->need_lsda_relative |
1274 | || ent->per_encoding_relative) | |
65765700 | 1275 | { |
f075ee0c | 1276 | char *aug; |
353057a5 | 1277 | unsigned int action, extra_string, extra_data; |
2c42be65 | 1278 | unsigned int per_width, per_encoding; |
65765700 | 1279 | |
9e2a4898 | 1280 | /* Need to find 'R' or 'L' augmentation's argument and modify |
65765700 | 1281 | DW_EH_PE_* value. */ |
353057a5 | 1282 | action = ((ent->make_relative ? 1 : 0) |
fda3ecf2 AM |
1283 | | (ent->need_lsda_relative ? 2 : 0) |
1284 | | (ent->per_encoding_relative ? 4 : 0)); | |
353057a5 RS |
1285 | extra_string = extra_augmentation_string_bytes (ent); |
1286 | extra_data = extra_augmentation_data_bytes (ent); | |
1287 | ||
65765700 JJ |
1288 | /* Skip length, id and version. */ |
1289 | buf += 9; | |
f075ee0c AM |
1290 | aug = (char *) buf; |
1291 | buf += strlen (aug) + 1; | |
2c42be65 RS |
1292 | skip_leb128 (&buf, end); |
1293 | skip_leb128 (&buf, end); | |
1294 | skip_leb128 (&buf, end); | |
65765700 JJ |
1295 | if (*aug == 'z') |
1296 | { | |
353057a5 RS |
1297 | /* The uleb128 will always be a single byte for the kind |
1298 | of augmentation strings that we're prepared to handle. */ | |
1299 | *buf++ += extra_data; | |
65765700 JJ |
1300 | aug++; |
1301 | } | |
1302 | ||
353057a5 RS |
1303 | /* Make room for the new augmentation string and data bytes. */ |
1304 | memmove (buf + extra_string + extra_data, buf, end - buf); | |
f075ee0c | 1305 | memmove (aug + extra_string, aug, buf - (bfd_byte *) aug); |
353057a5 | 1306 | buf += extra_string; |
2c42be65 | 1307 | end += extra_string + extra_data; |
353057a5 RS |
1308 | |
1309 | if (ent->add_augmentation_size) | |
1310 | { | |
1311 | *aug++ = 'z'; | |
1312 | *buf++ = extra_data - 1; | |
1313 | } | |
1314 | if (ent->add_fde_encoding) | |
1315 | { | |
1316 | BFD_ASSERT (action & 1); | |
1317 | *aug++ = 'R'; | |
1318 | *buf++ = DW_EH_PE_pcrel; | |
1319 | action &= ~1; | |
1320 | } | |
1321 | ||
9e2a4898 | 1322 | while (action) |
65765700 JJ |
1323 | switch (*aug++) |
1324 | { | |
1325 | case 'L': | |
9e2a4898 JJ |
1326 | if (action & 2) |
1327 | { | |
fda3ecf2 | 1328 | BFD_ASSERT (*buf == ent->lsda_encoding); |
9e2a4898 JJ |
1329 | *buf |= DW_EH_PE_pcrel; |
1330 | action &= ~2; | |
1331 | } | |
65765700 JJ |
1332 | buf++; |
1333 | break; | |
1334 | case 'P': | |
1335 | per_encoding = *buf++; | |
3472e2e9 | 1336 | per_width = get_DW_EH_PE_width (per_encoding, ptr_size); |
65765700 | 1337 | BFD_ASSERT (per_width != 0); |
09ae86c2 | 1338 | BFD_ASSERT (((per_encoding & 0x70) == DW_EH_PE_pcrel) |
fda3ecf2 | 1339 | == ent->per_encoding_relative); |
65765700 JJ |
1340 | if ((per_encoding & 0xf0) == DW_EH_PE_aligned) |
1341 | buf = (contents | |
1342 | + ((buf - contents + per_width - 1) | |
1343 | & ~((bfd_size_type) per_width - 1))); | |
09ae86c2 JJ |
1344 | if (action & 4) |
1345 | { | |
fda3ecf2 AM |
1346 | bfd_vma val; |
1347 | ||
1348 | val = read_value (abfd, buf, per_width, | |
1349 | get_DW_EH_PE_signed (per_encoding)); | |
1350 | val += ent->offset - ent->new_offset; | |
353057a5 | 1351 | val -= extra_string + extra_data; |
fda3ecf2 | 1352 | write_value (abfd, buf, val, per_width); |
09ae86c2 JJ |
1353 | action &= ~4; |
1354 | } | |
65765700 JJ |
1355 | buf += per_width; |
1356 | break; | |
9e2a4898 JJ |
1357 | case 'R': |
1358 | if (action & 1) | |
1359 | { | |
fda3ecf2 | 1360 | BFD_ASSERT (*buf == ent->fde_encoding); |
9e2a4898 JJ |
1361 | *buf |= DW_EH_PE_pcrel; |
1362 | action &= ~1; | |
1363 | } | |
1364 | buf++; | |
1365 | break; | |
63752a75 JJ |
1366 | case 'S': |
1367 | break; | |
65765700 JJ |
1368 | default: |
1369 | BFD_FAIL (); | |
1370 | } | |
65765700 JJ |
1371 | } |
1372 | } | |
353057a5 | 1373 | else |
65765700 JJ |
1374 | { |
1375 | /* FDE */ | |
fda3ecf2 | 1376 | bfd_vma value, address; |
9e2a4898 | 1377 | unsigned int width; |
ac685e6a | 1378 | bfd_byte *start; |
155eaaa0 | 1379 | struct eh_cie_fde *cie; |
65765700 | 1380 | |
b34976b6 | 1381 | /* Skip length. */ |
155eaaa0 | 1382 | cie = ent->u.fde.cie_inf; |
65765700 | 1383 | buf += 4; |
155eaaa0 | 1384 | value = ent->new_offset + 4 - cie->new_offset; |
fda3ecf2 | 1385 | bfd_put_32 (abfd, value, buf); |
65765700 | 1386 | buf += 4; |
fda3ecf2 AM |
1387 | width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); |
1388 | value = read_value (abfd, buf, width, | |
1389 | get_DW_EH_PE_signed (ent->fde_encoding)); | |
1390 | address = value; | |
9e2a4898 | 1391 | if (value) |
65765700 | 1392 | { |
fda3ecf2 | 1393 | switch (ent->fde_encoding & 0xf0) |
9e2a4898 JJ |
1394 | { |
1395 | case DW_EH_PE_indirect: | |
1396 | case DW_EH_PE_textrel: | |
1397 | BFD_ASSERT (hdr_info == NULL); | |
1398 | break; | |
1399 | case DW_EH_PE_datarel: | |
1400 | { | |
1401 | asection *got = bfd_get_section_by_name (abfd, ".got"); | |
1402 | ||
1403 | BFD_ASSERT (got != NULL); | |
1404 | address += got->vma; | |
1405 | } | |
1406 | break; | |
1407 | case DW_EH_PE_pcrel: | |
fda3ecf2 AM |
1408 | value += ent->offset - ent->new_offset; |
1409 | address += sec->output_section->vma + ent->offset + 8; | |
9e2a4898 JJ |
1410 | break; |
1411 | } | |
155eaaa0 | 1412 | if (cie->make_relative) |
fda3ecf2 | 1413 | value -= sec->output_section->vma + ent->new_offset + 8; |
9e2a4898 | 1414 | write_value (abfd, buf, value, width); |
65765700 JJ |
1415 | } |
1416 | ||
ac685e6a JJ |
1417 | start = buf; |
1418 | ||
65765700 JJ |
1419 | if (hdr_info) |
1420 | { | |
1421 | hdr_info->array[hdr_info->array_count].initial_loc = address; | |
1422 | hdr_info->array[hdr_info->array_count++].fde | |
fda3ecf2 | 1423 | = sec->output_section->vma + ent->new_offset; |
65765700 | 1424 | } |
9e2a4898 | 1425 | |
fda3ecf2 | 1426 | if ((ent->lsda_encoding & 0xf0) == DW_EH_PE_pcrel |
155eaaa0 | 1427 | || cie->need_lsda_relative) |
9e2a4898 | 1428 | { |
fda3ecf2 AM |
1429 | buf += ent->lsda_offset; |
1430 | width = get_DW_EH_PE_width (ent->lsda_encoding, ptr_size); | |
84f97cb6 | 1431 | value = read_value (abfd, buf, width, |
fda3ecf2 | 1432 | get_DW_EH_PE_signed (ent->lsda_encoding)); |
9e2a4898 JJ |
1433 | if (value) |
1434 | { | |
fda3ecf2 AM |
1435 | if ((ent->lsda_encoding & 0xf0) == DW_EH_PE_pcrel) |
1436 | value += ent->offset - ent->new_offset; | |
155eaaa0 | 1437 | else if (cie->need_lsda_relative) |
fda3ecf2 AM |
1438 | value -= (sec->output_section->vma + ent->new_offset + 8 |
1439 | + ent->lsda_offset); | |
9e2a4898 JJ |
1440 | write_value (abfd, buf, value, width); |
1441 | } | |
1442 | } | |
155eaaa0 | 1443 | else if (cie->add_augmentation_size) |
353057a5 RS |
1444 | { |
1445 | /* Skip the PC and length and insert a zero byte for the | |
1446 | augmentation size. */ | |
1447 | buf += width * 2; | |
1448 | memmove (buf + 1, buf, end - buf); | |
1449 | *buf = 0; | |
1450 | } | |
ac685e6a JJ |
1451 | |
1452 | if (ent->set_loc) | |
1453 | { | |
1454 | /* Adjust DW_CFA_set_loc. */ | |
1455 | unsigned int cnt, width; | |
1456 | bfd_vma new_offset; | |
1457 | ||
1458 | width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); | |
1459 | new_offset = ent->new_offset + 8 | |
1460 | + extra_augmentation_string_bytes (ent) | |
1461 | + extra_augmentation_data_bytes (ent); | |
1462 | ||
1463 | for (cnt = 1; cnt <= ent->set_loc[0]; cnt++) | |
1464 | { | |
1465 | bfd_vma value; | |
1466 | buf = start + ent->set_loc[cnt]; | |
1467 | ||
1468 | value = read_value (abfd, buf, width, | |
1469 | get_DW_EH_PE_signed (ent->fde_encoding)); | |
1470 | if (!value) | |
1471 | continue; | |
1472 | ||
1473 | if ((ent->fde_encoding & 0xf0) == DW_EH_PE_pcrel) | |
1474 | value += ent->offset + 8 - new_offset; | |
155eaaa0 | 1475 | if (cie->make_relative) |
ac685e6a JJ |
1476 | value -= sec->output_section->vma + new_offset |
1477 | + ent->set_loc[cnt]; | |
1478 | write_value (abfd, buf, value, width); | |
1479 | } | |
1480 | } | |
65765700 | 1481 | } |
65765700 JJ |
1482 | } |
1483 | ||
a34a056a L |
1484 | /* We don't align the section to its section alignment since the |
1485 | runtime library only expects all CIE/FDE records aligned at | |
4e591bc1 | 1486 | the pointer size. _bfd_elf_discard_section_eh_frame should |
a34a056a L |
1487 | have padded CIE/FDE records to multiple of pointer size with |
1488 | size_of_output_cie_fde. */ | |
1489 | if ((sec->size % ptr_size) != 0) | |
1490 | abort (); | |
a5eb27e6 | 1491 | |
65765700 | 1492 | return bfd_set_section_contents (abfd, sec->output_section, |
3472e2e9 AM |
1493 | contents, (file_ptr) sec->output_offset, |
1494 | sec->size); | |
65765700 JJ |
1495 | } |
1496 | ||
1497 | /* Helper function used to sort .eh_frame_hdr search table by increasing | |
1498 | VMA of FDE initial location. */ | |
1499 | ||
1500 | static int | |
c39a58e6 | 1501 | vma_compare (const void *a, const void *b) |
65765700 | 1502 | { |
c39a58e6 AM |
1503 | const struct eh_frame_array_ent *p = a; |
1504 | const struct eh_frame_array_ent *q = b; | |
65765700 JJ |
1505 | if (p->initial_loc > q->initial_loc) |
1506 | return 1; | |
1507 | if (p->initial_loc < q->initial_loc) | |
1508 | return -1; | |
1509 | return 0; | |
1510 | } | |
1511 | ||
1512 | /* Write out .eh_frame_hdr section. This must be called after | |
1513 | _bfd_elf_write_section_eh_frame has been called on all input | |
1514 | .eh_frame sections. | |
1515 | .eh_frame_hdr format: | |
1516 | ubyte version (currently 1) | |
1517 | ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of | |
1518 | .eh_frame section) | |
1519 | ubyte fde_count_enc (DW_EH_PE_* encoding of total FDE count | |
1520 | number (or DW_EH_PE_omit if there is no | |
1521 | binary search table computed)) | |
1522 | ubyte table_enc (DW_EH_PE_* encoding of binary search table, | |
1523 | or DW_EH_PE_omit if not present. | |
1524 | DW_EH_PE_datarel is using address of | |
1525 | .eh_frame_hdr section start as base) | |
1526 | [encoded] eh_frame_ptr (pointer to start of .eh_frame section) | |
1527 | optionally followed by: | |
1528 | [encoded] fde_count (total number of FDEs in .eh_frame section) | |
1529 | fde_count x [encoded] initial_loc, fde | |
1530 | (array of encoded pairs containing | |
1531 | FDE initial_location field and FDE address, | |
5ed6aba4 | 1532 | sorted by increasing initial_loc). */ |
65765700 | 1533 | |
b34976b6 | 1534 | bfd_boolean |
c39a58e6 | 1535 | _bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) |
65765700 | 1536 | { |
126495ed | 1537 | struct elf_link_hash_table *htab; |
65765700 | 1538 | struct eh_frame_hdr_info *hdr_info; |
126495ed | 1539 | asection *sec; |
65765700 JJ |
1540 | bfd_byte *contents; |
1541 | asection *eh_frame_sec; | |
1542 | bfd_size_type size; | |
5ed6aba4 | 1543 | bfd_boolean retval; |
ec3391e7 | 1544 | bfd_vma encoded_eh_frame; |
65765700 | 1545 | |
126495ed AM |
1546 | htab = elf_hash_table (info); |
1547 | hdr_info = &htab->eh_info; | |
1548 | sec = hdr_info->hdr_sec; | |
1549 | if (sec == NULL) | |
b34976b6 | 1550 | return TRUE; |
57a72197 | 1551 | |
65765700 JJ |
1552 | size = EH_FRAME_HDR_SIZE; |
1553 | if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) | |
1554 | size += 4 + hdr_info->fde_count * 8; | |
1555 | contents = bfd_malloc (size); | |
1556 | if (contents == NULL) | |
b34976b6 | 1557 | return FALSE; |
65765700 JJ |
1558 | |
1559 | eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame"); | |
1560 | if (eh_frame_sec == NULL) | |
5ed6aba4 NC |
1561 | { |
1562 | free (contents); | |
1563 | return FALSE; | |
1564 | } | |
65765700 JJ |
1565 | |
1566 | memset (contents, 0, EH_FRAME_HDR_SIZE); | |
5ed6aba4 | 1567 | contents[0] = 1; /* Version. */ |
ec3391e7 AO |
1568 | contents[1] = get_elf_backend_data (abfd)->elf_backend_encode_eh_address |
1569 | (abfd, info, eh_frame_sec, 0, sec, 4, | |
1570 | &encoded_eh_frame); /* .eh_frame offset. */ | |
1571 | ||
65765700 JJ |
1572 | if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) |
1573 | { | |
5ed6aba4 NC |
1574 | contents[2] = DW_EH_PE_udata4; /* FDE count encoding. */ |
1575 | contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; /* Search table enc. */ | |
65765700 JJ |
1576 | } |
1577 | else | |
1578 | { | |
1579 | contents[2] = DW_EH_PE_omit; | |
1580 | contents[3] = DW_EH_PE_omit; | |
1581 | } | |
ec3391e7 AO |
1582 | bfd_put_32 (abfd, encoded_eh_frame, contents + 4); |
1583 | ||
65765700 JJ |
1584 | if (contents[2] != DW_EH_PE_omit) |
1585 | { | |
1586 | unsigned int i; | |
1587 | ||
1588 | bfd_put_32 (abfd, hdr_info->fde_count, contents + EH_FRAME_HDR_SIZE); | |
1589 | qsort (hdr_info->array, hdr_info->fde_count, sizeof (*hdr_info->array), | |
1590 | vma_compare); | |
1591 | for (i = 0; i < hdr_info->fde_count; i++) | |
1592 | { | |
1593 | bfd_put_32 (abfd, | |
1594 | hdr_info->array[i].initial_loc | |
1595 | - sec->output_section->vma, | |
1596 | contents + EH_FRAME_HDR_SIZE + i * 8 + 4); | |
1597 | bfd_put_32 (abfd, | |
1598 | hdr_info->array[i].fde - sec->output_section->vma, | |
1599 | contents + EH_FRAME_HDR_SIZE + i * 8 + 8); | |
1600 | } | |
1601 | } | |
1602 | ||
5ed6aba4 NC |
1603 | retval = bfd_set_section_contents (abfd, sec->output_section, |
1604 | contents, (file_ptr) sec->output_offset, | |
eea6121a | 1605 | sec->size); |
5ed6aba4 NC |
1606 | free (contents); |
1607 | return retval; | |
65765700 | 1608 | } |
ec3391e7 | 1609 | |
8c946ed5 RS |
1610 | /* Return the width of FDE addresses. This is the default implementation. */ |
1611 | ||
1612 | unsigned int | |
1613 | _bfd_elf_eh_frame_address_size (bfd *abfd, asection *sec ATTRIBUTE_UNUSED) | |
1614 | { | |
1615 | return elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 ? 8 : 4; | |
1616 | } | |
1617 | ||
ec3391e7 AO |
1618 | /* Decide whether we can use a PC-relative encoding within the given |
1619 | EH frame section. This is the default implementation. */ | |
1620 | ||
1621 | bfd_boolean | |
1622 | _bfd_elf_can_make_relative (bfd *input_bfd ATTRIBUTE_UNUSED, | |
1623 | struct bfd_link_info *info ATTRIBUTE_UNUSED, | |
1624 | asection *eh_frame_section ATTRIBUTE_UNUSED) | |
1625 | { | |
1626 | return TRUE; | |
1627 | } | |
1628 | ||
1629 | /* Select an encoding for the given address. Preference is given to | |
1630 | PC-relative addressing modes. */ | |
1631 | ||
1632 | bfd_byte | |
1633 | _bfd_elf_encode_eh_address (bfd *abfd ATTRIBUTE_UNUSED, | |
1634 | struct bfd_link_info *info ATTRIBUTE_UNUSED, | |
1635 | asection *osec, bfd_vma offset, | |
1636 | asection *loc_sec, bfd_vma loc_offset, | |
1637 | bfd_vma *encoded) | |
1638 | { | |
1639 | *encoded = osec->vma + offset - | |
1640 | (loc_sec->output_section->vma + loc_sec->output_offset + loc_offset); | |
1641 | return DW_EH_PE_pcrel | DW_EH_PE_sdata4; | |
1642 | } |