Commit | Line | Data |
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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; | |
184d07da | 45 | unsigned int reloc_index; |
f137a54e | 46 | } personality; |
bce613b9 JJ |
47 | asection *output_sec; |
48 | struct eh_cie_fde *cie_inf; | |
49 | unsigned char per_encoding; | |
50 | unsigned char lsda_encoding; | |
51 | unsigned char fde_encoding; | |
52 | unsigned char initial_insn_length; | |
9f4b847e | 53 | unsigned char can_make_lsda_relative; |
bce613b9 JJ |
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++; | |
6b2cc140 | 286 | if (entry->u.cie.add_fde_encoding) |
353057a5 RS |
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; | |
6b2cc140 RS |
298 | if (entry->add_augmentation_size) |
299 | size++; | |
300 | if (entry->cie && entry->u.cie.add_fde_encoding) | |
301 | size++; | |
353057a5 RS |
302 | return size; |
303 | } | |
304 | ||
305 | /* Return the size that ENTRY will have in the output. ALIGNMENT is the | |
306 | required alignment of ENTRY in bytes. */ | |
307 | ||
308 | static unsigned int | |
309 | size_of_output_cie_fde (struct eh_cie_fde *entry, unsigned int alignment) | |
310 | { | |
311 | if (entry->removed) | |
312 | return 0; | |
313 | if (entry->size == 4) | |
314 | return 4; | |
315 | return (entry->size | |
316 | + extra_augmentation_string_bytes (entry) | |
317 | + extra_augmentation_data_bytes (entry) | |
318 | + alignment - 1) & -alignment; | |
319 | } | |
320 | ||
dcf507a6 RS |
321 | /* Assume that the bytes between *ITER and END are CFA instructions. |
322 | Try to move *ITER past the first instruction and return true on | |
323 | success. ENCODED_PTR_WIDTH gives the width of pointer entries. */ | |
324 | ||
325 | static bfd_boolean | |
326 | skip_cfa_op (bfd_byte **iter, bfd_byte *end, unsigned int encoded_ptr_width) | |
327 | { | |
328 | bfd_byte op; | |
329 | bfd_vma length; | |
330 | ||
331 | if (!read_byte (iter, end, &op)) | |
332 | return FALSE; | |
333 | ||
ac685e6a | 334 | switch (op & 0xc0 ? op & 0xc0 : op) |
dcf507a6 RS |
335 | { |
336 | case DW_CFA_nop: | |
337 | case DW_CFA_advance_loc: | |
338 | case DW_CFA_restore: | |
ac685e6a JJ |
339 | case DW_CFA_remember_state: |
340 | case DW_CFA_restore_state: | |
341 | case DW_CFA_GNU_window_save: | |
dcf507a6 RS |
342 | /* No arguments. */ |
343 | return TRUE; | |
344 | ||
345 | case DW_CFA_offset: | |
346 | case DW_CFA_restore_extended: | |
347 | case DW_CFA_undefined: | |
348 | case DW_CFA_same_value: | |
349 | case DW_CFA_def_cfa_register: | |
350 | case DW_CFA_def_cfa_offset: | |
351 | case DW_CFA_def_cfa_offset_sf: | |
352 | case DW_CFA_GNU_args_size: | |
353 | /* One leb128 argument. */ | |
354 | return skip_leb128 (iter, end); | |
355 | ||
ac685e6a JJ |
356 | case DW_CFA_val_offset: |
357 | case DW_CFA_val_offset_sf: | |
dcf507a6 RS |
358 | case DW_CFA_offset_extended: |
359 | case DW_CFA_register: | |
360 | case DW_CFA_def_cfa: | |
361 | case DW_CFA_offset_extended_sf: | |
362 | case DW_CFA_GNU_negative_offset_extended: | |
363 | case DW_CFA_def_cfa_sf: | |
364 | /* Two leb128 arguments. */ | |
365 | return (skip_leb128 (iter, end) | |
366 | && skip_leb128 (iter, end)); | |
367 | ||
368 | case DW_CFA_def_cfa_expression: | |
369 | /* A variable-length argument. */ | |
370 | return (read_uleb128 (iter, end, &length) | |
371 | && skip_bytes (iter, end, length)); | |
372 | ||
373 | case DW_CFA_expression: | |
ac685e6a | 374 | case DW_CFA_val_expression: |
dcf507a6 RS |
375 | /* A leb128 followed by a variable-length argument. */ |
376 | return (skip_leb128 (iter, end) | |
377 | && read_uleb128 (iter, end, &length) | |
378 | && skip_bytes (iter, end, length)); | |
379 | ||
380 | case DW_CFA_set_loc: | |
381 | return skip_bytes (iter, end, encoded_ptr_width); | |
382 | ||
383 | case DW_CFA_advance_loc1: | |
384 | return skip_bytes (iter, end, 1); | |
385 | ||
386 | case DW_CFA_advance_loc2: | |
387 | return skip_bytes (iter, end, 2); | |
388 | ||
389 | case DW_CFA_advance_loc4: | |
390 | return skip_bytes (iter, end, 4); | |
391 | ||
392 | case DW_CFA_MIPS_advance_loc8: | |
393 | return skip_bytes (iter, end, 8); | |
394 | ||
395 | default: | |
396 | return FALSE; | |
397 | } | |
398 | } | |
399 | ||
400 | /* Try to interpret the bytes between BUF and END as CFA instructions. | |
401 | If every byte makes sense, return a pointer to the first DW_CFA_nop | |
402 | padding byte, or END if there is no padding. Return null otherwise. | |
403 | ENCODED_PTR_WIDTH is as for skip_cfa_op. */ | |
404 | ||
405 | static bfd_byte * | |
ac685e6a JJ |
406 | skip_non_nops (bfd_byte *buf, bfd_byte *end, unsigned int encoded_ptr_width, |
407 | unsigned int *set_loc_count) | |
dcf507a6 RS |
408 | { |
409 | bfd_byte *last; | |
410 | ||
411 | last = buf; | |
412 | while (buf < end) | |
413 | if (*buf == DW_CFA_nop) | |
414 | buf++; | |
415 | else | |
416 | { | |
ac685e6a JJ |
417 | if (*buf == DW_CFA_set_loc) |
418 | ++*set_loc_count; | |
dcf507a6 RS |
419 | if (!skip_cfa_op (&buf, end, encoded_ptr_width)) |
420 | return 0; | |
421 | last = buf; | |
422 | } | |
423 | return last; | |
424 | } | |
425 | ||
ca92cecb RS |
426 | /* Called before calling _bfd_elf_parse_eh_frame on every input bfd's |
427 | .eh_frame section. */ | |
65765700 | 428 | |
ca92cecb RS |
429 | void |
430 | _bfd_elf_begin_eh_frame_parsing (struct bfd_link_info *info) | |
431 | { | |
432 | struct eh_frame_hdr_info *hdr_info; | |
433 | ||
434 | hdr_info = &elf_hash_table (info)->eh_info; | |
184d07da | 435 | hdr_info->merge_cies = !info->relocatable; |
ca92cecb RS |
436 | } |
437 | ||
438 | /* Try to parse .eh_frame section SEC, which belongs to ABFD. Store the | |
439 | information in the section's sec_info field on success. COOKIE | |
440 | describes the relocations in SEC. */ | |
441 | ||
442 | void | |
443 | _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, | |
444 | asection *sec, struct elf_reloc_cookie *cookie) | |
65765700 | 445 | { |
acfe5567 RS |
446 | #define REQUIRE(COND) \ |
447 | do \ | |
448 | if (!(COND)) \ | |
449 | goto free_no_table; \ | |
450 | while (0) | |
451 | ||
ca92cecb | 452 | bfd_byte *ehbuf = NULL, *buf, *end; |
bce613b9 | 453 | bfd_byte *last_fde; |
ca92cecb | 454 | struct eh_cie_fde *this_inf; |
bce613b9 | 455 | unsigned int hdr_length, hdr_id; |
184d07da RS |
456 | unsigned int cie_count; |
457 | struct cie *cie, *local_cies = NULL; | |
126495ed | 458 | struct elf_link_hash_table *htab; |
65765700 | 459 | struct eh_frame_hdr_info *hdr_info; |
68f69152 | 460 | struct eh_frame_sec_info *sec_info = NULL; |
65765700 | 461 | unsigned int ptr_size; |
ca92cecb RS |
462 | unsigned int num_cies; |
463 | unsigned int num_entries; | |
9d0a14d3 | 464 | elf_gc_mark_hook_fn gc_mark_hook; |
ca92cecb RS |
465 | |
466 | htab = elf_hash_table (info); | |
467 | hdr_info = &htab->eh_info; | |
468 | if (hdr_info->parsed_eh_frames) | |
469 | return; | |
65765700 | 470 | |
eea6121a | 471 | if (sec->size == 0) |
65765700 JJ |
472 | { |
473 | /* This file does not contain .eh_frame information. */ | |
ca92cecb | 474 | return; |
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. */ |
ca92cecb | 481 | return; |
65765700 JJ |
482 | } |
483 | ||
484 | /* Read the frame unwind information from abfd. */ | |
485 | ||
acfe5567 | 486 | REQUIRE (bfd_malloc_and_get_section (abfd, sec, &ehbuf)); |
68f69152 | 487 | |
eea6121a | 488 | if (sec->size >= 4 |
65765700 JJ |
489 | && bfd_get_32 (abfd, ehbuf) == 0 |
490 | && cookie->rel == cookie->relend) | |
491 | { | |
492 | /* Empty .eh_frame section. */ | |
493 | free (ehbuf); | |
ca92cecb | 494 | return; |
65765700 JJ |
495 | } |
496 | ||
65765700 JJ |
497 | /* If .eh_frame section size doesn't fit into int, we cannot handle |
498 | it (it would need to use 64-bit .eh_frame format anyway). */ | |
acfe5567 | 499 | REQUIRE (sec->size == (unsigned int) sec->size); |
65765700 | 500 | |
8c946ed5 RS |
501 | ptr_size = (get_elf_backend_data (abfd) |
502 | ->elf_backend_eh_frame_address_size (abfd, sec)); | |
503 | REQUIRE (ptr_size != 0); | |
504 | ||
ca92cecb RS |
505 | /* Go through the section contents and work out how many FDEs and |
506 | CIEs there are. */ | |
65765700 | 507 | buf = ehbuf; |
ca92cecb RS |
508 | end = ehbuf + sec->size; |
509 | num_cies = 0; | |
510 | num_entries = 0; | |
511 | while (buf != end) | |
512 | { | |
513 | num_entries++; | |
514 | ||
515 | /* Read the length of the entry. */ | |
516 | REQUIRE (skip_bytes (&buf, end, 4)); | |
517 | hdr_length = bfd_get_32 (abfd, buf - 4); | |
518 | ||
519 | /* 64-bit .eh_frame is not supported. */ | |
520 | REQUIRE (hdr_length != 0xffffffff); | |
521 | if (hdr_length == 0) | |
522 | break; | |
523 | ||
524 | REQUIRE (skip_bytes (&buf, end, 4)); | |
525 | hdr_id = bfd_get_32 (abfd, buf - 4); | |
526 | if (hdr_id == 0) | |
527 | num_cies++; | |
528 | ||
529 | REQUIRE (skip_bytes (&buf, end, hdr_length - 4)); | |
530 | } | |
531 | ||
65765700 | 532 | sec_info = bfd_zmalloc (sizeof (struct eh_frame_sec_info) |
ca92cecb | 533 | + (num_entries - 1) * sizeof (struct eh_cie_fde)); |
acfe5567 | 534 | REQUIRE (sec_info); |
eea6121a | 535 | |
184d07da RS |
536 | /* We need to have a "struct cie" for each CIE in this section. */ |
537 | local_cies = bfd_zmalloc (num_cies * sizeof (*local_cies)); | |
538 | REQUIRE (local_cies); | |
65765700 JJ |
539 | |
540 | #define ENSURE_NO_RELOCS(buf) \ | |
acfe5567 RS |
541 | REQUIRE (!(cookie->rel < cookie->relend \ |
542 | && (cookie->rel->r_offset \ | |
543 | < (bfd_size_type) ((buf) - ehbuf)) \ | |
544 | && cookie->rel->r_info != 0)) | |
65765700 JJ |
545 | |
546 | #define SKIP_RELOCS(buf) \ | |
547 | while (cookie->rel < cookie->relend \ | |
3472e2e9 | 548 | && (cookie->rel->r_offset \ |
65765700 JJ |
549 | < (bfd_size_type) ((buf) - ehbuf))) \ |
550 | cookie->rel++ | |
551 | ||
552 | #define GET_RELOC(buf) \ | |
553 | ((cookie->rel < cookie->relend \ | |
554 | && (cookie->rel->r_offset \ | |
3472e2e9 | 555 | == (bfd_size_type) ((buf) - ehbuf))) \ |
65765700 JJ |
556 | ? cookie->rel : NULL) |
557 | ||
ca92cecb | 558 | buf = ehbuf; |
184d07da | 559 | cie_count = 0; |
9d0a14d3 | 560 | gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook; |
ca92cecb | 561 | while ((bfd_size_type) (buf - ehbuf) != sec->size) |
65765700 | 562 | { |
f075ee0c | 563 | char *aug; |
ca92cecb | 564 | bfd_byte *start, *insns, *insns_end; |
2c42be65 | 565 | bfd_size_type length; |
ac685e6a | 566 | unsigned int set_loc_count; |
65765700 | 567 | |
fda3ecf2 | 568 | this_inf = sec_info->entry + sec_info->count; |
65765700 | 569 | last_fde = buf; |
bce613b9 | 570 | |
bce613b9 JJ |
571 | /* Read the length of the entry. */ |
572 | REQUIRE (skip_bytes (&buf, ehbuf + sec->size, 4)); | |
573 | hdr_length = bfd_get_32 (abfd, buf - 4); | |
acfe5567 | 574 | |
bce613b9 JJ |
575 | /* The CIE/FDE must be fully contained in this input section. */ |
576 | REQUIRE ((bfd_size_type) (buf - ehbuf) + hdr_length <= sec->size); | |
577 | end = buf + hdr_length; | |
65765700 | 578 | |
bce613b9 JJ |
579 | this_inf->offset = last_fde - ehbuf; |
580 | this_inf->size = 4 + hdr_length; | |
155eaaa0 | 581 | this_inf->reloc_index = cookie->rel - cookie->rels; |
bce613b9 JJ |
582 | |
583 | if (hdr_length == 0) | |
584 | { | |
585 | /* A zero-length CIE should only be found at the end of | |
586 | the section. */ | |
587 | REQUIRE ((bfd_size_type) (buf - ehbuf) == sec->size); | |
588 | ENSURE_NO_RELOCS (buf); | |
589 | sec_info->count++; | |
590 | break; | |
65765700 JJ |
591 | } |
592 | ||
bce613b9 JJ |
593 | REQUIRE (skip_bytes (&buf, end, 4)); |
594 | hdr_id = bfd_get_32 (abfd, buf - 4); | |
595 | ||
596 | if (hdr_id == 0) | |
65765700 JJ |
597 | { |
598 | unsigned int initial_insn_length; | |
599 | ||
600 | /* CIE */ | |
bce613b9 JJ |
601 | this_inf->cie = 1; |
602 | ||
184d07da RS |
603 | /* Point CIE to one of the section-local cie structures. */ |
604 | cie = local_cies + cie_count++; | |
605 | ||
ca92cecb | 606 | cie->cie_inf = this_inf; |
bce613b9 | 607 | cie->length = hdr_length; |
ca92cecb | 608 | cie->output_sec = sec->output_section; |
ac685e6a | 609 | start = buf; |
bce613b9 | 610 | REQUIRE (read_byte (&buf, end, &cie->version)); |
65765700 JJ |
611 | |
612 | /* Cannot handle unknown versions. */ | |
bce613b9 JJ |
613 | REQUIRE (cie->version == 1 || cie->version == 3); |
614 | REQUIRE (strlen ((char *) buf) < sizeof (cie->augmentation)); | |
65765700 | 615 | |
bce613b9 | 616 | strcpy (cie->augmentation, (char *) buf); |
f075ee0c | 617 | buf = (bfd_byte *) strchr ((char *) buf, '\0') + 1; |
65765700 JJ |
618 | ENSURE_NO_RELOCS (buf); |
619 | if (buf[0] == 'e' && buf[1] == 'h') | |
620 | { | |
621 | /* GCC < 3.0 .eh_frame CIE */ | |
622 | /* We cannot merge "eh" CIEs because __EXCEPTION_TABLE__ | |
623 | is private to each CIE, so we don't need it for anything. | |
624 | Just skip it. */ | |
2c42be65 | 625 | REQUIRE (skip_bytes (&buf, end, ptr_size)); |
65765700 JJ |
626 | SKIP_RELOCS (buf); |
627 | } | |
bce613b9 JJ |
628 | REQUIRE (read_uleb128 (&buf, end, &cie->code_align)); |
629 | REQUIRE (read_sleb128 (&buf, end, &cie->data_align)); | |
630 | if (cie->version == 1) | |
2c42be65 RS |
631 | { |
632 | REQUIRE (buf < end); | |
bce613b9 | 633 | cie->ra_column = *buf++; |
2c42be65 | 634 | } |
0da76f83 | 635 | else |
bce613b9 | 636 | REQUIRE (read_uleb128 (&buf, end, &cie->ra_column)); |
65765700 | 637 | ENSURE_NO_RELOCS (buf); |
bce613b9 JJ |
638 | cie->lsda_encoding = DW_EH_PE_omit; |
639 | cie->fde_encoding = DW_EH_PE_omit; | |
640 | cie->per_encoding = DW_EH_PE_omit; | |
641 | aug = cie->augmentation; | |
65765700 JJ |
642 | if (aug[0] != 'e' || aug[1] != 'h') |
643 | { | |
644 | if (*aug == 'z') | |
645 | { | |
646 | aug++; | |
bce613b9 | 647 | REQUIRE (read_uleb128 (&buf, end, &cie->augmentation_size)); |
65765700 JJ |
648 | ENSURE_NO_RELOCS (buf); |
649 | } | |
650 | ||
651 | while (*aug != '\0') | |
652 | switch (*aug++) | |
653 | { | |
654 | case 'L': | |
bce613b9 | 655 | REQUIRE (read_byte (&buf, end, &cie->lsda_encoding)); |
65765700 | 656 | ENSURE_NO_RELOCS (buf); |
bce613b9 | 657 | REQUIRE (get_DW_EH_PE_width (cie->lsda_encoding, ptr_size)); |
65765700 JJ |
658 | break; |
659 | case 'R': | |
bce613b9 | 660 | REQUIRE (read_byte (&buf, end, &cie->fde_encoding)); |
65765700 | 661 | ENSURE_NO_RELOCS (buf); |
bce613b9 | 662 | REQUIRE (get_DW_EH_PE_width (cie->fde_encoding, ptr_size)); |
65765700 | 663 | break; |
63752a75 JJ |
664 | case 'S': |
665 | break; | |
65765700 JJ |
666 | case 'P': |
667 | { | |
668 | int per_width; | |
669 | ||
bce613b9 JJ |
670 | REQUIRE (read_byte (&buf, end, &cie->per_encoding)); |
671 | per_width = get_DW_EH_PE_width (cie->per_encoding, | |
65765700 | 672 | ptr_size); |
acfe5567 | 673 | REQUIRE (per_width); |
bce613b9 | 674 | if ((cie->per_encoding & 0xf0) == DW_EH_PE_aligned) |
2c42be65 RS |
675 | { |
676 | length = -(buf - ehbuf) & (per_width - 1); | |
677 | REQUIRE (skip_bytes (&buf, end, length)); | |
678 | } | |
65765700 | 679 | ENSURE_NO_RELOCS (buf); |
f137a54e | 680 | /* Ensure we have a reloc here. */ |
184d07da RS |
681 | REQUIRE (GET_RELOC (buf)); |
682 | cie->personality.reloc_index | |
683 | = cookie->rel - cookie->rels; | |
684 | /* Cope with MIPS-style composite relocations. */ | |
685 | do | |
686 | cookie->rel++; | |
687 | while (GET_RELOC (buf) != NULL); | |
2c42be65 | 688 | REQUIRE (skip_bytes (&buf, end, per_width)); |
65765700 JJ |
689 | } |
690 | break; | |
691 | default: | |
692 | /* Unrecognized augmentation. Better bail out. */ | |
693 | goto free_no_table; | |
694 | } | |
695 | } | |
696 | ||
697 | /* For shared libraries, try to get rid of as many RELATIVE relocs | |
0bb2d96a | 698 | as possible. */ |
3472e2e9 | 699 | if (info->shared |
ec3391e7 AO |
700 | && (get_elf_backend_data (abfd) |
701 | ->elf_backend_can_make_relative_eh_frame | |
353057a5 RS |
702 | (abfd, info, sec))) |
703 | { | |
bce613b9 | 704 | if ((cie->fde_encoding & 0xf0) == DW_EH_PE_absptr) |
6b2cc140 | 705 | this_inf->make_relative = 1; |
353057a5 RS |
706 | /* If the CIE doesn't already have an 'R' entry, it's fairly |
707 | easy to add one, provided that there's no aligned data | |
708 | after the augmentation string. */ | |
bce613b9 JJ |
709 | else if (cie->fde_encoding == DW_EH_PE_omit |
710 | && (cie->per_encoding & 0xf0) != DW_EH_PE_aligned) | |
353057a5 | 711 | { |
bce613b9 | 712 | if (*cie->augmentation == 0) |
353057a5 | 713 | this_inf->add_augmentation_size = 1; |
6b2cc140 RS |
714 | this_inf->u.cie.add_fde_encoding = 1; |
715 | this_inf->make_relative = 1; | |
353057a5 RS |
716 | } |
717 | } | |
65765700 | 718 | |
0bb2d96a | 719 | if (info->shared |
ec3391e7 AO |
720 | && (get_elf_backend_data (abfd) |
721 | ->elf_backend_can_make_lsda_relative_eh_frame | |
722 | (abfd, info, sec)) | |
bce613b9 | 723 | && (cie->lsda_encoding & 0xf0) == DW_EH_PE_absptr) |
9f4b847e | 724 | cie->can_make_lsda_relative = 1; |
9e2a4898 | 725 | |
65765700 JJ |
726 | /* If FDE encoding was not specified, it defaults to |
727 | DW_EH_absptr. */ | |
bce613b9 JJ |
728 | if (cie->fde_encoding == DW_EH_PE_omit) |
729 | cie->fde_encoding = DW_EH_PE_absptr; | |
65765700 | 730 | |
dcf507a6 | 731 | initial_insn_length = end - buf; |
bce613b9 | 732 | if (initial_insn_length <= sizeof (cie->initial_instructions)) |
65765700 | 733 | { |
bce613b9 JJ |
734 | cie->initial_insn_length = initial_insn_length; |
735 | memcpy (cie->initial_instructions, buf, initial_insn_length); | |
65765700 | 736 | } |
dcf507a6 | 737 | insns = buf; |
65765700 JJ |
738 | buf += initial_insn_length; |
739 | ENSURE_NO_RELOCS (buf); | |
ca92cecb | 740 | |
184d07da RS |
741 | if (hdr_info->merge_cies) |
742 | this_inf->u.cie.u.full_cie = cie; | |
6b2cc140 | 743 | this_inf->u.cie.per_encoding_relative |
ca92cecb | 744 | = (cie->per_encoding & 0x70) == DW_EH_PE_pcrel; |
65765700 JJ |
745 | } |
746 | else | |
747 | { | |
9d0a14d3 RS |
748 | asection *rsec; |
749 | ||
bce613b9 JJ |
750 | /* Find the corresponding CIE. */ |
751 | unsigned int cie_offset = this_inf->offset + 4 - hdr_id; | |
184d07da RS |
752 | for (cie = local_cies; cie < local_cies + cie_count; cie++) |
753 | if (cie_offset == cie->cie_inf->offset) | |
bce613b9 JJ |
754 | break; |
755 | ||
756 | /* Ensure this FDE references one of the CIEs in this input | |
757 | section. */ | |
184d07da RS |
758 | REQUIRE (cie != local_cies + cie_count); |
759 | this_inf->u.fde.cie_inf = cie->cie_inf; | |
760 | this_inf->make_relative = cie->cie_inf->make_relative; | |
6b2cc140 | 761 | this_inf->add_augmentation_size |
184d07da | 762 | = cie->cie_inf->add_augmentation_size; |
65765700 JJ |
763 | |
764 | ENSURE_NO_RELOCS (buf); | |
acfe5567 | 765 | REQUIRE (GET_RELOC (buf)); |
fda3ecf2 | 766 | |
9d0a14d3 RS |
767 | /* Chain together the FDEs for each section. */ |
768 | rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie); | |
769 | REQUIRE (rsec && rsec->owner == abfd); | |
770 | this_inf->u.fde.next_for_section = elf_fde_list (rsec); | |
771 | elf_fde_list (rsec) = this_inf; | |
772 | ||
2c42be65 RS |
773 | /* Skip the initial location and address range. */ |
774 | start = buf; | |
bce613b9 | 775 | length = get_DW_EH_PE_width (cie->fde_encoding, ptr_size); |
2c42be65 RS |
776 | REQUIRE (skip_bytes (&buf, end, 2 * length)); |
777 | ||
778 | /* Skip the augmentation size, if present. */ | |
bce613b9 | 779 | if (cie->augmentation[0] == 'z') |
dcf507a6 RS |
780 | REQUIRE (read_uleb128 (&buf, end, &length)); |
781 | else | |
782 | length = 0; | |
2c42be65 RS |
783 | |
784 | /* Of the supported augmentation characters above, only 'L' | |
785 | adds augmentation data to the FDE. This code would need to | |
786 | be adjusted if any future augmentations do the same thing. */ | |
bce613b9 | 787 | if (cie->lsda_encoding != DW_EH_PE_omit) |
dcf507a6 | 788 | { |
9f4b847e RS |
789 | SKIP_RELOCS (buf); |
790 | if (cie->can_make_lsda_relative && GET_RELOC (buf)) | |
791 | cie->cie_inf->u.cie.make_lsda_relative = 1; | |
dcf507a6 RS |
792 | this_inf->lsda_offset = buf - start; |
793 | /* If there's no 'z' augmentation, we don't know where the | |
794 | CFA insns begin. Assume no padding. */ | |
bce613b9 | 795 | if (cie->augmentation[0] != 'z') |
dcf507a6 RS |
796 | length = end - buf; |
797 | } | |
798 | ||
799 | /* Skip over the augmentation data. */ | |
800 | REQUIRE (skip_bytes (&buf, end, length)); | |
801 | insns = buf; | |
9e2a4898 | 802 | |
bce613b9 | 803 | buf = last_fde + 4 + hdr_length; |
65765700 JJ |
804 | SKIP_RELOCS (buf); |
805 | } | |
806 | ||
dcf507a6 RS |
807 | /* Try to interpret the CFA instructions and find the first |
808 | padding nop. Shrink this_inf's size so that it doesn't | |
ac685e6a | 809 | include the padding. */ |
bce613b9 | 810 | length = get_DW_EH_PE_width (cie->fde_encoding, ptr_size); |
ac685e6a JJ |
811 | set_loc_count = 0; |
812 | insns_end = skip_non_nops (insns, end, length, &set_loc_count); | |
813 | /* If we don't understand the CFA instructions, we can't know | |
814 | what needs to be adjusted there. */ | |
815 | if (insns_end == NULL | |
816 | /* For the time being we don't support DW_CFA_set_loc in | |
817 | CIE instructions. */ | |
818 | || (set_loc_count && this_inf->cie)) | |
819 | goto free_no_table; | |
820 | this_inf->size -= end - insns_end; | |
bce613b9 JJ |
821 | if (insns_end != end && this_inf->cie) |
822 | { | |
823 | cie->initial_insn_length -= end - insns_end; | |
824 | cie->length -= end - insns_end; | |
825 | } | |
ac685e6a | 826 | if (set_loc_count |
bce613b9 | 827 | && ((cie->fde_encoding & 0xf0) == DW_EH_PE_pcrel |
6b2cc140 | 828 | || this_inf->make_relative)) |
ac685e6a JJ |
829 | { |
830 | unsigned int cnt; | |
831 | bfd_byte *p; | |
832 | ||
833 | this_inf->set_loc = bfd_malloc ((set_loc_count + 1) | |
834 | * sizeof (unsigned int)); | |
835 | REQUIRE (this_inf->set_loc); | |
836 | this_inf->set_loc[0] = set_loc_count; | |
837 | p = insns; | |
838 | cnt = 0; | |
839 | while (p < end) | |
840 | { | |
841 | if (*p == DW_CFA_set_loc) | |
842 | this_inf->set_loc[++cnt] = p + 1 - start; | |
843 | REQUIRE (skip_cfa_op (&p, end, length)); | |
844 | } | |
845 | } | |
dcf507a6 | 846 | |
ca92cecb | 847 | this_inf->removed = 1; |
bce613b9 JJ |
848 | this_inf->fde_encoding = cie->fde_encoding; |
849 | this_inf->lsda_encoding = cie->lsda_encoding; | |
65765700 JJ |
850 | sec_info->count++; |
851 | } | |
ca92cecb | 852 | BFD_ASSERT (sec_info->count == num_entries); |
184d07da | 853 | BFD_ASSERT (cie_count == num_cies); |
65765700 JJ |
854 | |
855 | elf_section_data (sec)->sec_info = sec_info; | |
68bfbfcc | 856 | sec->sec_info_type = ELF_INFO_TYPE_EH_FRAME; |
184d07da RS |
857 | if (hdr_info->merge_cies) |
858 | { | |
859 | sec_info->cies = local_cies; | |
860 | local_cies = NULL; | |
861 | } | |
ca92cecb | 862 | goto success; |
65765700 | 863 | |
ca92cecb RS |
864 | free_no_table: |
865 | (*info->callbacks->einfo) | |
866 | (_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"), | |
867 | abfd, sec); | |
868 | hdr_info->table = FALSE; | |
869 | if (sec_info) | |
870 | free (sec_info); | |
871 | success: | |
872 | if (ehbuf) | |
873 | free (ehbuf); | |
ca92cecb RS |
874 | if (local_cies) |
875 | free (local_cies); | |
876 | #undef REQUIRE | |
877 | } | |
bce613b9 | 878 | |
ca92cecb RS |
879 | /* Finish a pass over all .eh_frame sections. */ |
880 | ||
881 | void | |
882 | _bfd_elf_end_eh_frame_parsing (struct bfd_link_info *info) | |
883 | { | |
884 | struct eh_frame_hdr_info *hdr_info; | |
885 | ||
886 | hdr_info = &elf_hash_table (info)->eh_info; | |
ca92cecb RS |
887 | hdr_info->parsed_eh_frames = TRUE; |
888 | } | |
bce613b9 | 889 | |
9d0a14d3 RS |
890 | /* Mark all relocations against CIE or FDE ENT, which occurs in |
891 | .eh_frame section SEC. COOKIE describes the relocations in SEC; | |
892 | its "rel" field can be changed freely. */ | |
893 | ||
894 | static bfd_boolean | |
895 | mark_entry (struct bfd_link_info *info, asection *sec, | |
896 | struct eh_cie_fde *ent, elf_gc_mark_hook_fn gc_mark_hook, | |
897 | struct elf_reloc_cookie *cookie) | |
898 | { | |
899 | for (cookie->rel = cookie->rels + ent->reloc_index; | |
900 | cookie->rel < cookie->relend | |
901 | && cookie->rel->r_offset < ent->offset + ent->size; | |
902 | cookie->rel++) | |
903 | if (!_bfd_elf_gc_mark_reloc (info, sec, gc_mark_hook, cookie)) | |
904 | return FALSE; | |
905 | ||
906 | return TRUE; | |
907 | } | |
908 | ||
909 | /* Mark all the relocations against FDEs that relate to code in input | |
910 | section SEC. The FDEs belong to .eh_frame section EH_FRAME, whose | |
911 | relocations are described by COOKIE. */ | |
912 | ||
913 | bfd_boolean | |
914 | _bfd_elf_gc_mark_fdes (struct bfd_link_info *info, asection *sec, | |
915 | asection *eh_frame, elf_gc_mark_hook_fn gc_mark_hook, | |
916 | struct elf_reloc_cookie *cookie) | |
917 | { | |
184d07da | 918 | struct eh_cie_fde *fde, *cie; |
9d0a14d3 RS |
919 | |
920 | for (fde = elf_fde_list (sec); fde; fde = fde->u.fde.next_for_section) | |
921 | { | |
922 | if (!mark_entry (info, eh_frame, fde, gc_mark_hook, cookie)) | |
923 | return FALSE; | |
924 | ||
925 | /* At this stage, all cie_inf fields point to local CIEs, so we | |
926 | can use the same cookie to refer to them. */ | |
927 | cie = fde->u.fde.cie_inf; | |
184d07da | 928 | if (!cie->u.cie.gc_mark) |
9d0a14d3 | 929 | { |
184d07da | 930 | cie->u.cie.gc_mark = 1; |
9d0a14d3 RS |
931 | if (!mark_entry (info, eh_frame, cie, gc_mark_hook, cookie)) |
932 | return FALSE; | |
933 | } | |
934 | } | |
935 | return TRUE; | |
936 | } | |
937 | ||
184d07da RS |
938 | /* Input section SEC of ABFD is an .eh_frame section that contains the |
939 | CIE described by CIE_INF. Return a version of CIE_INF that is going | |
940 | to be kept in the output, adding CIE_INF to the output if necessary. | |
941 | ||
942 | HDR_INFO is the .eh_frame_hdr information and COOKIE describes the | |
943 | relocations in REL. */ | |
944 | ||
945 | static struct eh_cie_fde * | |
946 | find_merged_cie (bfd *abfd, asection *sec, | |
947 | struct eh_frame_hdr_info *hdr_info, | |
948 | struct elf_reloc_cookie *cookie, | |
949 | struct eh_cie_fde *cie_inf) | |
950 | { | |
951 | unsigned long r_symndx; | |
952 | struct cie *cie, *new_cie; | |
953 | Elf_Internal_Rela *rel; | |
954 | void **loc; | |
955 | ||
956 | /* Use CIE_INF if we have already decided to keep it. */ | |
957 | if (!cie_inf->removed) | |
958 | return cie_inf; | |
959 | ||
960 | /* If we have merged CIE_INF with another CIE, use that CIE instead. */ | |
961 | if (cie_inf->u.cie.merged) | |
962 | return cie_inf->u.cie.u.merged_with; | |
963 | ||
964 | cie = cie_inf->u.cie.u.full_cie; | |
965 | ||
966 | /* Assume we will need to keep CIE_INF. */ | |
967 | cie_inf->removed = 0; | |
968 | cie_inf->u.cie.u.sec = sec; | |
969 | ||
970 | /* If we are not merging CIEs, use CIE_INF. */ | |
971 | if (cie == NULL) | |
972 | return cie_inf; | |
973 | ||
974 | if (cie->per_encoding != DW_EH_PE_omit) | |
975 | { | |
976 | /* Work out the address of personality routine, either as an absolute | |
977 | value or as a symbol. */ | |
978 | rel = cookie->rels + cie->personality.reloc_index; | |
979 | memset (&cie->personality, 0, sizeof (cie->personality)); | |
980 | #ifdef BFD64 | |
981 | if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64) | |
982 | r_symndx = ELF64_R_SYM (rel->r_info); | |
983 | else | |
984 | #endif | |
985 | r_symndx = ELF32_R_SYM (rel->r_info); | |
986 | if (r_symndx >= cookie->locsymcount | |
987 | || ELF_ST_BIND (cookie->locsyms[r_symndx].st_info) != STB_LOCAL) | |
988 | { | |
989 | struct elf_link_hash_entry *h; | |
990 | ||
991 | r_symndx -= cookie->extsymoff; | |
992 | h = cookie->sym_hashes[r_symndx]; | |
993 | ||
994 | while (h->root.type == bfd_link_hash_indirect | |
995 | || h->root.type == bfd_link_hash_warning) | |
996 | h = (struct elf_link_hash_entry *) h->root.u.i.link; | |
997 | ||
998 | cie->personality.h = h; | |
999 | } | |
1000 | else | |
1001 | { | |
1002 | Elf_Internal_Sym *sym; | |
1003 | asection *sym_sec; | |
1004 | ||
1005 | sym = &cookie->locsyms[r_symndx]; | |
1006 | sym_sec = bfd_section_from_elf_index (abfd, sym->st_shndx); | |
1007 | if (sym_sec == NULL) | |
1008 | return cie_inf; | |
1009 | ||
1010 | if (sym_sec->kept_section != NULL) | |
1011 | sym_sec = sym_sec->kept_section; | |
1012 | if (sym_sec->output_section == NULL) | |
1013 | return cie_inf; | |
1014 | ||
1015 | cie->local_personality = 1; | |
1016 | cie->personality.val = (sym->st_value | |
1017 | + sym_sec->output_offset | |
1018 | + sym_sec->output_section->vma); | |
1019 | } | |
1020 | } | |
1021 | ||
1022 | /* See if we can merge this CIE with an earlier one. */ | |
1023 | cie->output_sec = sec->output_section; | |
1024 | cie_compute_hash (cie); | |
1025 | if (hdr_info->cies == NULL) | |
1026 | { | |
1027 | hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free); | |
1028 | if (hdr_info->cies == NULL) | |
1029 | return cie_inf; | |
1030 | } | |
1031 | loc = htab_find_slot_with_hash (hdr_info->cies, cie, cie->hash, INSERT); | |
1032 | if (loc == NULL) | |
1033 | return cie_inf; | |
1034 | ||
1035 | new_cie = (struct cie *) *loc; | |
1036 | if (new_cie == NULL) | |
1037 | { | |
1038 | /* Keep CIE_INF and record it in the hash table. */ | |
1039 | new_cie = malloc (sizeof (struct cie)); | |
1040 | if (new_cie == NULL) | |
1041 | return cie_inf; | |
1042 | ||
1043 | memcpy (new_cie, cie, sizeof (struct cie)); | |
1044 | *loc = new_cie; | |
1045 | } | |
1046 | else | |
1047 | { | |
1048 | /* Merge CIE_INF with NEW_CIE->CIE_INF. */ | |
1049 | cie_inf->removed = 1; | |
1050 | cie_inf->u.cie.merged = 1; | |
1051 | cie_inf->u.cie.u.merged_with = new_cie->cie_inf; | |
1052 | if (cie_inf->u.cie.make_lsda_relative) | |
1053 | new_cie->cie_inf->u.cie.make_lsda_relative = 1; | |
1054 | } | |
1055 | return new_cie->cie_inf; | |
1056 | } | |
1057 | ||
ca92cecb RS |
1058 | /* This function is called for each input file before the .eh_frame |
1059 | section is relocated. It discards duplicate CIEs and FDEs for discarded | |
1060 | functions. The function returns TRUE iff any entries have been | |
1061 | deleted. */ | |
1062 | ||
1063 | bfd_boolean | |
1064 | _bfd_elf_discard_section_eh_frame | |
1065 | (bfd *abfd, struct bfd_link_info *info, asection *sec, | |
1066 | bfd_boolean (*reloc_symbol_deleted_p) (bfd_vma, void *), | |
1067 | struct elf_reloc_cookie *cookie) | |
1068 | { | |
184d07da | 1069 | struct eh_cie_fde *ent; |
ca92cecb RS |
1070 | struct eh_frame_sec_info *sec_info; |
1071 | struct eh_frame_hdr_info *hdr_info; | |
1072 | unsigned int ptr_size, offset; | |
1073 | ||
1074 | sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info; | |
1075 | if (sec_info == NULL) | |
1076 | return FALSE; | |
1077 | ||
1078 | hdr_info = &elf_hash_table (info)->eh_info; | |
fda3ecf2 | 1079 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) |
ca92cecb | 1080 | if (!ent->cie) |
fda3ecf2 | 1081 | { |
ca92cecb RS |
1082 | cookie->rel = cookie->rels + ent->reloc_index; |
1083 | BFD_ASSERT (cookie->rel < cookie->relend | |
1084 | && cookie->rel->r_offset == ent->offset + 8); | |
1085 | if (!(*reloc_symbol_deleted_p) (ent->offset + 8, cookie)) | |
bce613b9 | 1086 | { |
ca92cecb RS |
1087 | if (info->shared |
1088 | && (((ent->fde_encoding & 0xf0) == DW_EH_PE_absptr | |
6b2cc140 | 1089 | && ent->make_relative == 0) |
ca92cecb RS |
1090 | || (ent->fde_encoding & 0xf0) == DW_EH_PE_aligned)) |
1091 | { | |
1092 | /* If a shared library uses absolute pointers | |
1093 | which we cannot turn into PC relative, | |
1094 | don't create the binary search table, | |
1095 | since it is affected by runtime relocations. */ | |
1096 | hdr_info->table = FALSE; | |
1097 | (*info->callbacks->einfo) | |
1098 | (_("%P: fde encoding in %B(%A) prevents .eh_frame_hdr" | |
1099 | " table being created.\n"), abfd, sec); | |
1100 | } | |
1101 | ent->removed = 0; | |
1102 | hdr_info->fde_count++; | |
184d07da RS |
1103 | ent->u.fde.cie_inf = find_merged_cie (abfd, sec, hdr_info, cookie, |
1104 | ent->u.fde.cie_inf); | |
bce613b9 | 1105 | } |
ca92cecb RS |
1106 | } |
1107 | ||
184d07da RS |
1108 | if (sec_info->cies) |
1109 | { | |
1110 | free (sec_info->cies); | |
1111 | sec_info->cies = NULL; | |
1112 | } | |
1113 | ||
ca92cecb RS |
1114 | ptr_size = (get_elf_backend_data (sec->owner) |
1115 | ->elf_backend_eh_frame_address_size (sec->owner, sec)); | |
1116 | offset = 0; | |
1117 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) | |
1118 | if (!ent->removed) | |
1119 | { | |
353057a5 RS |
1120 | ent->new_offset = offset; |
1121 | offset += size_of_output_cie_fde (ent, ptr_size); | |
fda3ecf2 | 1122 | } |
65765700 | 1123 | |
eea6121a | 1124 | sec->rawsize = sec->size; |
353057a5 | 1125 | sec->size = offset; |
353057a5 | 1126 | return offset != sec->rawsize; |
65765700 JJ |
1127 | } |
1128 | ||
1129 | /* This function is called for .eh_frame_hdr section after | |
1130 | _bfd_elf_discard_section_eh_frame has been called on all .eh_frame | |
1131 | input sections. It finalizes the size of .eh_frame_hdr section. */ | |
1132 | ||
b34976b6 | 1133 | bfd_boolean |
c39a58e6 | 1134 | _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) |
65765700 | 1135 | { |
126495ed | 1136 | struct elf_link_hash_table *htab; |
65765700 | 1137 | struct eh_frame_hdr_info *hdr_info; |
126495ed | 1138 | asection *sec; |
65765700 | 1139 | |
126495ed AM |
1140 | htab = elf_hash_table (info); |
1141 | hdr_info = &htab->eh_info; | |
bce613b9 | 1142 | |
184d07da RS |
1143 | if (hdr_info->cies != NULL) |
1144 | { | |
1145 | htab_delete (hdr_info->cies); | |
1146 | hdr_info->cies = NULL; | |
1147 | } | |
1148 | ||
126495ed AM |
1149 | sec = hdr_info->hdr_sec; |
1150 | if (sec == NULL) | |
b34976b6 | 1151 | return FALSE; |
126495ed | 1152 | |
eea6121a | 1153 | sec->size = EH_FRAME_HDR_SIZE; |
65765700 | 1154 | if (hdr_info->table) |
eea6121a | 1155 | sec->size += 4 + hdr_info->fde_count * 8; |
65765700 | 1156 | |
126495ed | 1157 | elf_tdata (abfd)->eh_frame_hdr = sec; |
b34976b6 | 1158 | return TRUE; |
65765700 JJ |
1159 | } |
1160 | ||
68f69152 JJ |
1161 | /* This function is called from size_dynamic_sections. |
1162 | It needs to decide whether .eh_frame_hdr should be output or not, | |
8423293d AM |
1163 | because when the dynamic symbol table has been sized it is too late |
1164 | to strip sections. */ | |
68f69152 | 1165 | |
b34976b6 | 1166 | bfd_boolean |
c39a58e6 | 1167 | _bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info) |
68f69152 | 1168 | { |
126495ed | 1169 | asection *o; |
68f69152 | 1170 | bfd *abfd; |
126495ed | 1171 | struct elf_link_hash_table *htab; |
68f69152 JJ |
1172 | struct eh_frame_hdr_info *hdr_info; |
1173 | ||
126495ed AM |
1174 | htab = elf_hash_table (info); |
1175 | hdr_info = &htab->eh_info; | |
1176 | if (hdr_info->hdr_sec == NULL) | |
b34976b6 | 1177 | return TRUE; |
68f69152 | 1178 | |
126495ed AM |
1179 | if (bfd_is_abs_section (hdr_info->hdr_sec->output_section)) |
1180 | { | |
1181 | hdr_info->hdr_sec = NULL; | |
b34976b6 | 1182 | return TRUE; |
126495ed | 1183 | } |
68f69152 JJ |
1184 | |
1185 | abfd = NULL; | |
1186 | if (info->eh_frame_hdr) | |
1187 | for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next) | |
1188 | { | |
1189 | /* Count only sections which have at least a single CIE or FDE. | |
1190 | There cannot be any CIE or FDE <= 8 bytes. */ | |
1191 | o = bfd_get_section_by_name (abfd, ".eh_frame"); | |
eea6121a | 1192 | if (o && o->size > 8 && !bfd_is_abs_section (o->output_section)) |
68f69152 JJ |
1193 | break; |
1194 | } | |
1195 | ||
1196 | if (abfd == NULL) | |
1197 | { | |
8423293d | 1198 | hdr_info->hdr_sec->flags |= SEC_EXCLUDE; |
126495ed | 1199 | hdr_info->hdr_sec = NULL; |
b34976b6 | 1200 | return TRUE; |
68f69152 | 1201 | } |
126495ed | 1202 | |
b34976b6 AM |
1203 | hdr_info->table = TRUE; |
1204 | return TRUE; | |
68f69152 JJ |
1205 | } |
1206 | ||
65765700 JJ |
1207 | /* Adjust an address in the .eh_frame section. Given OFFSET within |
1208 | SEC, this returns the new offset in the adjusted .eh_frame section, | |
1209 | or -1 if the address refers to a CIE/FDE which has been removed | |
1210 | or to offset with dynamic relocation which is no longer needed. */ | |
1211 | ||
1212 | bfd_vma | |
c39a58e6 | 1213 | _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED, |
92e4ec35 | 1214 | struct bfd_link_info *info, |
c39a58e6 AM |
1215 | asection *sec, |
1216 | bfd_vma offset) | |
65765700 JJ |
1217 | { |
1218 | struct eh_frame_sec_info *sec_info; | |
92e4ec35 AM |
1219 | struct elf_link_hash_table *htab; |
1220 | struct eh_frame_hdr_info *hdr_info; | |
65765700 JJ |
1221 | unsigned int lo, hi, mid; |
1222 | ||
68bfbfcc | 1223 | if (sec->sec_info_type != ELF_INFO_TYPE_EH_FRAME) |
65765700 | 1224 | return offset; |
c39a58e6 | 1225 | sec_info = elf_section_data (sec)->sec_info; |
65765700 | 1226 | |
eea6121a AM |
1227 | if (offset >= sec->rawsize) |
1228 | return offset - sec->rawsize + sec->size; | |
65765700 | 1229 | |
92e4ec35 AM |
1230 | htab = elf_hash_table (info); |
1231 | hdr_info = &htab->eh_info; | |
92e4ec35 | 1232 | |
65765700 JJ |
1233 | lo = 0; |
1234 | hi = sec_info->count; | |
1235 | mid = 0; | |
1236 | while (lo < hi) | |
1237 | { | |
1238 | mid = (lo + hi) / 2; | |
1239 | if (offset < sec_info->entry[mid].offset) | |
1240 | hi = mid; | |
1241 | else if (offset | |
1242 | >= sec_info->entry[mid].offset + sec_info->entry[mid].size) | |
1243 | lo = mid + 1; | |
1244 | else | |
1245 | break; | |
1246 | } | |
1247 | ||
1248 | BFD_ASSERT (lo < hi); | |
1249 | ||
1250 | /* FDE or CIE was removed. */ | |
1251 | if (sec_info->entry[mid].removed) | |
1252 | return (bfd_vma) -1; | |
1253 | ||
1254 | /* If converting to DW_EH_PE_pcrel, there will be no need for run-time | |
1255 | relocation against FDE's initial_location field. */ | |
fda3ecf2 | 1256 | if (!sec_info->entry[mid].cie |
6b2cc140 | 1257 | && sec_info->entry[mid].make_relative |
353057a5 RS |
1258 | && offset == sec_info->entry[mid].offset + 8) |
1259 | return (bfd_vma) -2; | |
65765700 | 1260 | |
9e2a4898 JJ |
1261 | /* If converting LSDA pointers to DW_EH_PE_pcrel, there will be no need |
1262 | for run-time relocation against LSDA field. */ | |
fda3ecf2 | 1263 | if (!sec_info->entry[mid].cie |
9f4b847e RS |
1264 | && sec_info->entry[mid].u.fde.cie_inf->u.cie.make_lsda_relative |
1265 | && offset == (sec_info->entry[mid].offset + 8 | |
1266 | + sec_info->entry[mid].lsda_offset)) | |
1267 | return (bfd_vma) -2; | |
9e2a4898 | 1268 | |
ac685e6a JJ |
1269 | /* If converting to DW_EH_PE_pcrel, there will be no need for run-time |
1270 | relocation against DW_CFA_set_loc's arguments. */ | |
1271 | if (sec_info->entry[mid].set_loc | |
6b2cc140 | 1272 | && sec_info->entry[mid].make_relative |
ac685e6a JJ |
1273 | && (offset >= sec_info->entry[mid].offset + 8 |
1274 | + sec_info->entry[mid].set_loc[1])) | |
1275 | { | |
1276 | unsigned int cnt; | |
1277 | ||
1278 | for (cnt = 1; cnt <= sec_info->entry[mid].set_loc[0]; cnt++) | |
1279 | if (offset == sec_info->entry[mid].offset + 8 | |
1280 | + sec_info->entry[mid].set_loc[cnt]) | |
1281 | return (bfd_vma) -2; | |
1282 | } | |
1283 | ||
353057a5 | 1284 | /* Any new augmentation bytes go before the first relocation. */ |
c68836a9 | 1285 | return (offset + sec_info->entry[mid].new_offset |
353057a5 RS |
1286 | - sec_info->entry[mid].offset |
1287 | + extra_augmentation_string_bytes (sec_info->entry + mid) | |
1288 | + extra_augmentation_data_bytes (sec_info->entry + mid)); | |
65765700 JJ |
1289 | } |
1290 | ||
1291 | /* Write out .eh_frame section. This is called with the relocated | |
1292 | contents. */ | |
1293 | ||
b34976b6 | 1294 | bfd_boolean |
c39a58e6 AM |
1295 | _bfd_elf_write_section_eh_frame (bfd *abfd, |
1296 | struct bfd_link_info *info, | |
1297 | asection *sec, | |
1298 | bfd_byte *contents) | |
65765700 JJ |
1299 | { |
1300 | struct eh_frame_sec_info *sec_info; | |
126495ed | 1301 | struct elf_link_hash_table *htab; |
65765700 | 1302 | struct eh_frame_hdr_info *hdr_info; |
65765700 | 1303 | unsigned int ptr_size; |
fda3ecf2 | 1304 | struct eh_cie_fde *ent; |
65765700 | 1305 | |
68bfbfcc | 1306 | if (sec->sec_info_type != ELF_INFO_TYPE_EH_FRAME) |
c39a58e6 | 1307 | return bfd_set_section_contents (abfd, sec->output_section, contents, |
eea6121a | 1308 | sec->output_offset, sec->size); |
8c946ed5 RS |
1309 | |
1310 | ptr_size = (get_elf_backend_data (abfd) | |
1311 | ->elf_backend_eh_frame_address_size (abfd, sec)); | |
1312 | BFD_ASSERT (ptr_size != 0); | |
1313 | ||
c39a58e6 | 1314 | sec_info = elf_section_data (sec)->sec_info; |
126495ed AM |
1315 | htab = elf_hash_table (info); |
1316 | hdr_info = &htab->eh_info; | |
3472e2e9 | 1317 | |
126495ed AM |
1318 | if (hdr_info->table && hdr_info->array == NULL) |
1319 | hdr_info->array | |
1320 | = bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array)); | |
1321 | if (hdr_info->array == NULL) | |
1322 | hdr_info = NULL; | |
65765700 | 1323 | |
353057a5 RS |
1324 | /* The new offsets can be bigger or smaller than the original offsets. |
1325 | We therefore need to make two passes over the section: one backward | |
1326 | pass to move entries up and one forward pass to move entries down. | |
1327 | The two passes won't interfere with each other because entries are | |
1328 | not reordered */ | |
1329 | for (ent = sec_info->entry + sec_info->count; ent-- != sec_info->entry;) | |
1330 | if (!ent->removed && ent->new_offset > ent->offset) | |
fc802241 | 1331 | memmove (contents + ent->new_offset, contents + ent->offset, ent->size); |
353057a5 RS |
1332 | |
1333 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) | |
1334 | if (!ent->removed && ent->new_offset < ent->offset) | |
fc802241 | 1335 | memmove (contents + ent->new_offset, contents + ent->offset, ent->size); |
353057a5 | 1336 | |
fda3ecf2 | 1337 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) |
65765700 | 1338 | { |
353057a5 RS |
1339 | unsigned char *buf, *end; |
1340 | unsigned int new_size; | |
1341 | ||
fda3ecf2 AM |
1342 | if (ent->removed) |
1343 | continue; | |
1344 | ||
353057a5 RS |
1345 | if (ent->size == 4) |
1346 | { | |
1347 | /* Any terminating FDE must be at the end of the section. */ | |
1348 | BFD_ASSERT (ent == sec_info->entry + sec_info->count - 1); | |
1349 | continue; | |
1350 | } | |
1351 | ||
fc802241 | 1352 | buf = contents + ent->new_offset; |
353057a5 RS |
1353 | end = buf + ent->size; |
1354 | new_size = size_of_output_cie_fde (ent, ptr_size); | |
1355 | ||
a34a056a L |
1356 | /* Update the size. It may be shrinked. */ |
1357 | bfd_put_32 (abfd, new_size - 4, buf); | |
1358 | ||
1359 | /* Filling the extra bytes with DW_CFA_nops. */ | |
353057a5 | 1360 | if (new_size != ent->size) |
a34a056a | 1361 | memset (end, 0, new_size - ent->size); |
353057a5 | 1362 | |
fda3ecf2 | 1363 | if (ent->cie) |
65765700 JJ |
1364 | { |
1365 | /* CIE */ | |
353057a5 | 1366 | if (ent->make_relative |
9f4b847e | 1367 | || ent->u.cie.make_lsda_relative |
6b2cc140 | 1368 | || ent->u.cie.per_encoding_relative) |
65765700 | 1369 | { |
f075ee0c | 1370 | char *aug; |
353057a5 | 1371 | unsigned int action, extra_string, extra_data; |
2c42be65 | 1372 | unsigned int per_width, per_encoding; |
65765700 | 1373 | |
9e2a4898 | 1374 | /* Need to find 'R' or 'L' augmentation's argument and modify |
65765700 | 1375 | DW_EH_PE_* value. */ |
353057a5 | 1376 | action = ((ent->make_relative ? 1 : 0) |
9f4b847e | 1377 | | (ent->u.cie.make_lsda_relative ? 2 : 0) |
6b2cc140 | 1378 | | (ent->u.cie.per_encoding_relative ? 4 : 0)); |
353057a5 RS |
1379 | extra_string = extra_augmentation_string_bytes (ent); |
1380 | extra_data = extra_augmentation_data_bytes (ent); | |
1381 | ||
65765700 JJ |
1382 | /* Skip length, id and version. */ |
1383 | buf += 9; | |
f075ee0c AM |
1384 | aug = (char *) buf; |
1385 | buf += strlen (aug) + 1; | |
2c42be65 RS |
1386 | skip_leb128 (&buf, end); |
1387 | skip_leb128 (&buf, end); | |
1388 | skip_leb128 (&buf, end); | |
65765700 JJ |
1389 | if (*aug == 'z') |
1390 | { | |
353057a5 RS |
1391 | /* The uleb128 will always be a single byte for the kind |
1392 | of augmentation strings that we're prepared to handle. */ | |
1393 | *buf++ += extra_data; | |
65765700 JJ |
1394 | aug++; |
1395 | } | |
1396 | ||
353057a5 RS |
1397 | /* Make room for the new augmentation string and data bytes. */ |
1398 | memmove (buf + extra_string + extra_data, buf, end - buf); | |
f075ee0c | 1399 | memmove (aug + extra_string, aug, buf - (bfd_byte *) aug); |
353057a5 | 1400 | buf += extra_string; |
2c42be65 | 1401 | end += extra_string + extra_data; |
353057a5 RS |
1402 | |
1403 | if (ent->add_augmentation_size) | |
1404 | { | |
1405 | *aug++ = 'z'; | |
1406 | *buf++ = extra_data - 1; | |
1407 | } | |
6b2cc140 | 1408 | if (ent->u.cie.add_fde_encoding) |
353057a5 RS |
1409 | { |
1410 | BFD_ASSERT (action & 1); | |
1411 | *aug++ = 'R'; | |
1412 | *buf++ = DW_EH_PE_pcrel; | |
1413 | action &= ~1; | |
1414 | } | |
1415 | ||
9e2a4898 | 1416 | while (action) |
65765700 JJ |
1417 | switch (*aug++) |
1418 | { | |
1419 | case 'L': | |
9e2a4898 JJ |
1420 | if (action & 2) |
1421 | { | |
fda3ecf2 | 1422 | BFD_ASSERT (*buf == ent->lsda_encoding); |
9e2a4898 JJ |
1423 | *buf |= DW_EH_PE_pcrel; |
1424 | action &= ~2; | |
1425 | } | |
65765700 JJ |
1426 | buf++; |
1427 | break; | |
1428 | case 'P': | |
1429 | per_encoding = *buf++; | |
3472e2e9 | 1430 | per_width = get_DW_EH_PE_width (per_encoding, ptr_size); |
65765700 | 1431 | BFD_ASSERT (per_width != 0); |
09ae86c2 | 1432 | BFD_ASSERT (((per_encoding & 0x70) == DW_EH_PE_pcrel) |
6b2cc140 | 1433 | == ent->u.cie.per_encoding_relative); |
65765700 JJ |
1434 | if ((per_encoding & 0xf0) == DW_EH_PE_aligned) |
1435 | buf = (contents | |
1436 | + ((buf - contents + per_width - 1) | |
1437 | & ~((bfd_size_type) per_width - 1))); | |
09ae86c2 JJ |
1438 | if (action & 4) |
1439 | { | |
fda3ecf2 AM |
1440 | bfd_vma val; |
1441 | ||
1442 | val = read_value (abfd, buf, per_width, | |
1443 | get_DW_EH_PE_signed (per_encoding)); | |
1444 | val += ent->offset - ent->new_offset; | |
353057a5 | 1445 | val -= extra_string + extra_data; |
fda3ecf2 | 1446 | write_value (abfd, buf, val, per_width); |
09ae86c2 JJ |
1447 | action &= ~4; |
1448 | } | |
65765700 JJ |
1449 | buf += per_width; |
1450 | break; | |
9e2a4898 JJ |
1451 | case 'R': |
1452 | if (action & 1) | |
1453 | { | |
fda3ecf2 | 1454 | BFD_ASSERT (*buf == ent->fde_encoding); |
9e2a4898 JJ |
1455 | *buf |= DW_EH_PE_pcrel; |
1456 | action &= ~1; | |
1457 | } | |
1458 | buf++; | |
1459 | break; | |
63752a75 JJ |
1460 | case 'S': |
1461 | break; | |
65765700 JJ |
1462 | default: |
1463 | BFD_FAIL (); | |
1464 | } | |
65765700 JJ |
1465 | } |
1466 | } | |
353057a5 | 1467 | else |
65765700 JJ |
1468 | { |
1469 | /* FDE */ | |
fda3ecf2 | 1470 | bfd_vma value, address; |
9e2a4898 | 1471 | unsigned int width; |
ac685e6a | 1472 | bfd_byte *start; |
155eaaa0 | 1473 | struct eh_cie_fde *cie; |
65765700 | 1474 | |
b34976b6 | 1475 | /* Skip length. */ |
155eaaa0 | 1476 | cie = ent->u.fde.cie_inf; |
65765700 | 1477 | buf += 4; |
fc802241 RS |
1478 | value = ((ent->new_offset + sec->output_offset + 4) |
1479 | - (cie->new_offset + cie->u.cie.u.sec->output_offset)); | |
fda3ecf2 | 1480 | bfd_put_32 (abfd, value, buf); |
65765700 | 1481 | buf += 4; |
fda3ecf2 AM |
1482 | width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); |
1483 | value = read_value (abfd, buf, width, | |
1484 | get_DW_EH_PE_signed (ent->fde_encoding)); | |
1485 | address = value; | |
9e2a4898 | 1486 | if (value) |
65765700 | 1487 | { |
fda3ecf2 | 1488 | switch (ent->fde_encoding & 0xf0) |
9e2a4898 JJ |
1489 | { |
1490 | case DW_EH_PE_indirect: | |
1491 | case DW_EH_PE_textrel: | |
1492 | BFD_ASSERT (hdr_info == NULL); | |
1493 | break; | |
1494 | case DW_EH_PE_datarel: | |
1495 | { | |
1496 | asection *got = bfd_get_section_by_name (abfd, ".got"); | |
1497 | ||
1498 | BFD_ASSERT (got != NULL); | |
1499 | address += got->vma; | |
1500 | } | |
1501 | break; | |
1502 | case DW_EH_PE_pcrel: | |
fda3ecf2 | 1503 | value += ent->offset - ent->new_offset; |
fc802241 RS |
1504 | address += (sec->output_section->vma |
1505 | + sec->output_offset | |
1506 | + ent->offset + 8); | |
9e2a4898 JJ |
1507 | break; |
1508 | } | |
6b2cc140 | 1509 | if (ent->make_relative) |
fc802241 RS |
1510 | value -= (sec->output_section->vma |
1511 | + sec->output_offset | |
1512 | + ent->new_offset + 8); | |
9e2a4898 | 1513 | write_value (abfd, buf, value, width); |
65765700 JJ |
1514 | } |
1515 | ||
ac685e6a JJ |
1516 | start = buf; |
1517 | ||
65765700 JJ |
1518 | if (hdr_info) |
1519 | { | |
1520 | hdr_info->array[hdr_info->array_count].initial_loc = address; | |
1521 | hdr_info->array[hdr_info->array_count++].fde | |
fc802241 RS |
1522 | = (sec->output_section->vma |
1523 | + sec->output_offset | |
1524 | + ent->new_offset); | |
65765700 | 1525 | } |
9e2a4898 | 1526 | |
fda3ecf2 | 1527 | if ((ent->lsda_encoding & 0xf0) == DW_EH_PE_pcrel |
9f4b847e | 1528 | || cie->u.cie.make_lsda_relative) |
9e2a4898 | 1529 | { |
fda3ecf2 AM |
1530 | buf += ent->lsda_offset; |
1531 | width = get_DW_EH_PE_width (ent->lsda_encoding, ptr_size); | |
84f97cb6 | 1532 | value = read_value (abfd, buf, width, |
fda3ecf2 | 1533 | get_DW_EH_PE_signed (ent->lsda_encoding)); |
9e2a4898 JJ |
1534 | if (value) |
1535 | { | |
fda3ecf2 AM |
1536 | if ((ent->lsda_encoding & 0xf0) == DW_EH_PE_pcrel) |
1537 | value += ent->offset - ent->new_offset; | |
9f4b847e | 1538 | else if (cie->u.cie.make_lsda_relative) |
fc802241 RS |
1539 | value -= (sec->output_section->vma |
1540 | + sec->output_offset | |
1541 | + ent->new_offset + 8 + ent->lsda_offset); | |
9e2a4898 JJ |
1542 | write_value (abfd, buf, value, width); |
1543 | } | |
1544 | } | |
6b2cc140 | 1545 | else if (ent->add_augmentation_size) |
353057a5 RS |
1546 | { |
1547 | /* Skip the PC and length and insert a zero byte for the | |
1548 | augmentation size. */ | |
1549 | buf += width * 2; | |
1550 | memmove (buf + 1, buf, end - buf); | |
1551 | *buf = 0; | |
1552 | } | |
ac685e6a JJ |
1553 | |
1554 | if (ent->set_loc) | |
1555 | { | |
1556 | /* Adjust DW_CFA_set_loc. */ | |
1557 | unsigned int cnt, width; | |
1558 | bfd_vma new_offset; | |
1559 | ||
1560 | width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); | |
1561 | new_offset = ent->new_offset + 8 | |
1562 | + extra_augmentation_string_bytes (ent) | |
1563 | + extra_augmentation_data_bytes (ent); | |
1564 | ||
1565 | for (cnt = 1; cnt <= ent->set_loc[0]; cnt++) | |
1566 | { | |
1567 | bfd_vma value; | |
1568 | buf = start + ent->set_loc[cnt]; | |
1569 | ||
1570 | value = read_value (abfd, buf, width, | |
1571 | get_DW_EH_PE_signed (ent->fde_encoding)); | |
1572 | if (!value) | |
1573 | continue; | |
1574 | ||
1575 | if ((ent->fde_encoding & 0xf0) == DW_EH_PE_pcrel) | |
1576 | value += ent->offset + 8 - new_offset; | |
6b2cc140 | 1577 | if (ent->make_relative) |
fc802241 RS |
1578 | value -= (sec->output_section->vma |
1579 | + sec->output_offset | |
1580 | + new_offset + ent->set_loc[cnt]); | |
ac685e6a JJ |
1581 | write_value (abfd, buf, value, width); |
1582 | } | |
1583 | } | |
65765700 | 1584 | } |
65765700 JJ |
1585 | } |
1586 | ||
a34a056a L |
1587 | /* We don't align the section to its section alignment since the |
1588 | runtime library only expects all CIE/FDE records aligned at | |
4e591bc1 | 1589 | the pointer size. _bfd_elf_discard_section_eh_frame should |
a34a056a L |
1590 | have padded CIE/FDE records to multiple of pointer size with |
1591 | size_of_output_cie_fde. */ | |
1592 | if ((sec->size % ptr_size) != 0) | |
1593 | abort (); | |
a5eb27e6 | 1594 | |
65765700 | 1595 | return bfd_set_section_contents (abfd, sec->output_section, |
3472e2e9 AM |
1596 | contents, (file_ptr) sec->output_offset, |
1597 | sec->size); | |
65765700 JJ |
1598 | } |
1599 | ||
1600 | /* Helper function used to sort .eh_frame_hdr search table by increasing | |
1601 | VMA of FDE initial location. */ | |
1602 | ||
1603 | static int | |
c39a58e6 | 1604 | vma_compare (const void *a, const void *b) |
65765700 | 1605 | { |
c39a58e6 AM |
1606 | const struct eh_frame_array_ent *p = a; |
1607 | const struct eh_frame_array_ent *q = b; | |
65765700 JJ |
1608 | if (p->initial_loc > q->initial_loc) |
1609 | return 1; | |
1610 | if (p->initial_loc < q->initial_loc) | |
1611 | return -1; | |
1612 | return 0; | |
1613 | } | |
1614 | ||
1615 | /* Write out .eh_frame_hdr section. This must be called after | |
1616 | _bfd_elf_write_section_eh_frame has been called on all input | |
1617 | .eh_frame sections. | |
1618 | .eh_frame_hdr format: | |
1619 | ubyte version (currently 1) | |
1620 | ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of | |
1621 | .eh_frame section) | |
1622 | ubyte fde_count_enc (DW_EH_PE_* encoding of total FDE count | |
1623 | number (or DW_EH_PE_omit if there is no | |
1624 | binary search table computed)) | |
1625 | ubyte table_enc (DW_EH_PE_* encoding of binary search table, | |
1626 | or DW_EH_PE_omit if not present. | |
1627 | DW_EH_PE_datarel is using address of | |
1628 | .eh_frame_hdr section start as base) | |
1629 | [encoded] eh_frame_ptr (pointer to start of .eh_frame section) | |
1630 | optionally followed by: | |
1631 | [encoded] fde_count (total number of FDEs in .eh_frame section) | |
1632 | fde_count x [encoded] initial_loc, fde | |
1633 | (array of encoded pairs containing | |
1634 | FDE initial_location field and FDE address, | |
5ed6aba4 | 1635 | sorted by increasing initial_loc). */ |
65765700 | 1636 | |
b34976b6 | 1637 | bfd_boolean |
c39a58e6 | 1638 | _bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) |
65765700 | 1639 | { |
126495ed | 1640 | struct elf_link_hash_table *htab; |
65765700 | 1641 | struct eh_frame_hdr_info *hdr_info; |
126495ed | 1642 | asection *sec; |
65765700 JJ |
1643 | bfd_byte *contents; |
1644 | asection *eh_frame_sec; | |
1645 | bfd_size_type size; | |
5ed6aba4 | 1646 | bfd_boolean retval; |
ec3391e7 | 1647 | bfd_vma encoded_eh_frame; |
65765700 | 1648 | |
126495ed AM |
1649 | htab = elf_hash_table (info); |
1650 | hdr_info = &htab->eh_info; | |
1651 | sec = hdr_info->hdr_sec; | |
1652 | if (sec == NULL) | |
b34976b6 | 1653 | return TRUE; |
57a72197 | 1654 | |
65765700 JJ |
1655 | size = EH_FRAME_HDR_SIZE; |
1656 | if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) | |
1657 | size += 4 + hdr_info->fde_count * 8; | |
1658 | contents = bfd_malloc (size); | |
1659 | if (contents == NULL) | |
b34976b6 | 1660 | return FALSE; |
65765700 JJ |
1661 | |
1662 | eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame"); | |
1663 | if (eh_frame_sec == NULL) | |
5ed6aba4 NC |
1664 | { |
1665 | free (contents); | |
1666 | return FALSE; | |
1667 | } | |
65765700 JJ |
1668 | |
1669 | memset (contents, 0, EH_FRAME_HDR_SIZE); | |
5ed6aba4 | 1670 | contents[0] = 1; /* Version. */ |
ec3391e7 AO |
1671 | contents[1] = get_elf_backend_data (abfd)->elf_backend_encode_eh_address |
1672 | (abfd, info, eh_frame_sec, 0, sec, 4, | |
1673 | &encoded_eh_frame); /* .eh_frame offset. */ | |
1674 | ||
65765700 JJ |
1675 | if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) |
1676 | { | |
5ed6aba4 NC |
1677 | contents[2] = DW_EH_PE_udata4; /* FDE count encoding. */ |
1678 | contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; /* Search table enc. */ | |
65765700 JJ |
1679 | } |
1680 | else | |
1681 | { | |
1682 | contents[2] = DW_EH_PE_omit; | |
1683 | contents[3] = DW_EH_PE_omit; | |
1684 | } | |
ec3391e7 AO |
1685 | bfd_put_32 (abfd, encoded_eh_frame, contents + 4); |
1686 | ||
65765700 JJ |
1687 | if (contents[2] != DW_EH_PE_omit) |
1688 | { | |
1689 | unsigned int i; | |
1690 | ||
1691 | bfd_put_32 (abfd, hdr_info->fde_count, contents + EH_FRAME_HDR_SIZE); | |
1692 | qsort (hdr_info->array, hdr_info->fde_count, sizeof (*hdr_info->array), | |
1693 | vma_compare); | |
1694 | for (i = 0; i < hdr_info->fde_count; i++) | |
1695 | { | |
1696 | bfd_put_32 (abfd, | |
1697 | hdr_info->array[i].initial_loc | |
1698 | - sec->output_section->vma, | |
1699 | contents + EH_FRAME_HDR_SIZE + i * 8 + 4); | |
1700 | bfd_put_32 (abfd, | |
1701 | hdr_info->array[i].fde - sec->output_section->vma, | |
1702 | contents + EH_FRAME_HDR_SIZE + i * 8 + 8); | |
1703 | } | |
1704 | } | |
1705 | ||
5ed6aba4 NC |
1706 | retval = bfd_set_section_contents (abfd, sec->output_section, |
1707 | contents, (file_ptr) sec->output_offset, | |
eea6121a | 1708 | sec->size); |
5ed6aba4 NC |
1709 | free (contents); |
1710 | return retval; | |
65765700 | 1711 | } |
ec3391e7 | 1712 | |
8c946ed5 RS |
1713 | /* Return the width of FDE addresses. This is the default implementation. */ |
1714 | ||
1715 | unsigned int | |
1716 | _bfd_elf_eh_frame_address_size (bfd *abfd, asection *sec ATTRIBUTE_UNUSED) | |
1717 | { | |
1718 | return elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 ? 8 : 4; | |
1719 | } | |
1720 | ||
ec3391e7 AO |
1721 | /* Decide whether we can use a PC-relative encoding within the given |
1722 | EH frame section. This is the default implementation. */ | |
1723 | ||
1724 | bfd_boolean | |
1725 | _bfd_elf_can_make_relative (bfd *input_bfd ATTRIBUTE_UNUSED, | |
1726 | struct bfd_link_info *info ATTRIBUTE_UNUSED, | |
1727 | asection *eh_frame_section ATTRIBUTE_UNUSED) | |
1728 | { | |
1729 | return TRUE; | |
1730 | } | |
1731 | ||
1732 | /* Select an encoding for the given address. Preference is given to | |
1733 | PC-relative addressing modes. */ | |
1734 | ||
1735 | bfd_byte | |
1736 | _bfd_elf_encode_eh_address (bfd *abfd ATTRIBUTE_UNUSED, | |
1737 | struct bfd_link_info *info ATTRIBUTE_UNUSED, | |
1738 | asection *osec, bfd_vma offset, | |
1739 | asection *loc_sec, bfd_vma loc_offset, | |
1740 | bfd_vma *encoded) | |
1741 | { | |
1742 | *encoded = osec->vma + offset - | |
1743 | (loc_sec->output_section->vma + loc_sec->output_offset + loc_offset); | |
1744 | return DW_EH_PE_pcrel | DW_EH_PE_sdata4; | |
1745 | } |