Commit | Line | Data |
---|---|---|
65765700 | 1 | /* .eh_frame section optimization. |
4b95cf5c | 2 | Copyright (C) 2001-2014 Free Software Foundation, Inc. |
65765700 JJ |
3 | Written by Jakub Jelinek <jakub@redhat.com>. |
4 | ||
5ed6aba4 | 5 | This file is part of BFD, the Binary File Descriptor library. |
65765700 | 6 | |
5ed6aba4 NC |
7 | This program is free software; you can redistribute it and/or modify |
8 | it under the terms of the GNU General Public License as published by | |
cd123cb7 | 9 | the Free Software Foundation; either version 3 of the License, or |
5ed6aba4 | 10 | (at your option) any later version. |
65765700 | 11 | |
5ed6aba4 NC |
12 | This program is distributed in the hope that it will be useful, |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
65765700 | 16 | |
5ed6aba4 NC |
17 | You should have received a copy of the GNU General Public License |
18 | along with this program; if not, write to the Free Software | |
cd123cb7 NC |
19 | Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
20 | MA 02110-1301, USA. */ | |
65765700 | 21 | |
65765700 | 22 | #include "sysdep.h" |
3db64b00 | 23 | #include "bfd.h" |
65765700 JJ |
24 | #include "libbfd.h" |
25 | #include "elf-bfd.h" | |
fa8f86ff | 26 | #include "dwarf2.h" |
65765700 JJ |
27 | |
28 | #define EH_FRAME_HDR_SIZE 8 | |
29 | ||
bce613b9 JJ |
30 | struct cie |
31 | { | |
32 | unsigned int length; | |
33 | unsigned int hash; | |
34 | unsigned char version; | |
f137a54e | 35 | unsigned char local_personality; |
bce613b9 JJ |
36 | char augmentation[20]; |
37 | bfd_vma code_align; | |
38 | bfd_signed_vma data_align; | |
39 | bfd_vma ra_column; | |
40 | bfd_vma augmentation_size; | |
f137a54e AM |
41 | union { |
42 | struct elf_link_hash_entry *h; | |
5087d529 AM |
43 | struct { |
44 | unsigned int bfd_id; | |
45 | unsigned int index; | |
46 | } sym; | |
184d07da | 47 | unsigned int reloc_index; |
f137a54e | 48 | } personality; |
bce613b9 JJ |
49 | asection *output_sec; |
50 | struct eh_cie_fde *cie_inf; | |
51 | unsigned char per_encoding; | |
52 | unsigned char lsda_encoding; | |
53 | unsigned char fde_encoding; | |
54 | unsigned char initial_insn_length; | |
9f4b847e | 55 | unsigned char can_make_lsda_relative; |
bce613b9 JJ |
56 | unsigned char initial_instructions[50]; |
57 | }; | |
58 | ||
59 | ||
60 | ||
2c42be65 RS |
61 | /* If *ITER hasn't reached END yet, read the next byte into *RESULT and |
62 | move onto the next byte. Return true on success. */ | |
63 | ||
64 | static inline bfd_boolean | |
65 | read_byte (bfd_byte **iter, bfd_byte *end, unsigned char *result) | |
66 | { | |
67 | if (*iter >= end) | |
68 | return FALSE; | |
69 | *result = *((*iter)++); | |
70 | return TRUE; | |
71 | } | |
72 | ||
73 | /* Move *ITER over LENGTH bytes, or up to END, whichever is closer. | |
74 | Return true it was possible to move LENGTH bytes. */ | |
75 | ||
76 | static inline bfd_boolean | |
77 | skip_bytes (bfd_byte **iter, bfd_byte *end, bfd_size_type length) | |
78 | { | |
79 | if ((bfd_size_type) (end - *iter) < length) | |
80 | { | |
81 | *iter = end; | |
82 | return FALSE; | |
83 | } | |
84 | *iter += length; | |
85 | return TRUE; | |
86 | } | |
87 | ||
88 | /* Move *ITER over an leb128, stopping at END. Return true if the end | |
89 | of the leb128 was found. */ | |
90 | ||
91 | static bfd_boolean | |
92 | skip_leb128 (bfd_byte **iter, bfd_byte *end) | |
93 | { | |
94 | unsigned char byte; | |
95 | do | |
96 | if (!read_byte (iter, end, &byte)) | |
97 | return FALSE; | |
98 | while (byte & 0x80); | |
99 | return TRUE; | |
100 | } | |
101 | ||
102 | /* Like skip_leb128, but treat the leb128 as an unsigned value and | |
103 | store it in *VALUE. */ | |
104 | ||
105 | static bfd_boolean | |
106 | read_uleb128 (bfd_byte **iter, bfd_byte *end, bfd_vma *value) | |
107 | { | |
108 | bfd_byte *start, *p; | |
109 | ||
110 | start = *iter; | |
111 | if (!skip_leb128 (iter, end)) | |
112 | return FALSE; | |
113 | ||
114 | p = *iter; | |
115 | *value = *--p; | |
116 | while (p > start) | |
117 | *value = (*value << 7) | (*--p & 0x7f); | |
118 | ||
119 | return TRUE; | |
120 | } | |
121 | ||
122 | /* Like read_uleb128, but for signed values. */ | |
123 | ||
124 | static bfd_boolean | |
125 | read_sleb128 (bfd_byte **iter, bfd_byte *end, bfd_signed_vma *value) | |
126 | { | |
127 | bfd_byte *start, *p; | |
128 | ||
129 | start = *iter; | |
130 | if (!skip_leb128 (iter, end)) | |
131 | return FALSE; | |
132 | ||
133 | p = *iter; | |
134 | *value = ((*--p & 0x7f) ^ 0x40) - 0x40; | |
135 | while (p > start) | |
136 | *value = (*value << 7) | (*--p & 0x7f); | |
137 | ||
138 | return TRUE; | |
139 | } | |
65765700 JJ |
140 | |
141 | /* Return 0 if either encoding is variable width, or not yet known to bfd. */ | |
142 | ||
143 | static | |
c39a58e6 | 144 | int get_DW_EH_PE_width (int encoding, int ptr_size) |
65765700 JJ |
145 | { |
146 | /* DW_EH_PE_ values of 0x60 and 0x70 weren't defined at the time .eh_frame | |
147 | was added to bfd. */ | |
148 | if ((encoding & 0x60) == 0x60) | |
149 | return 0; | |
150 | ||
151 | switch (encoding & 7) | |
152 | { | |
153 | case DW_EH_PE_udata2: return 2; | |
154 | case DW_EH_PE_udata4: return 4; | |
155 | case DW_EH_PE_udata8: return 8; | |
156 | case DW_EH_PE_absptr: return ptr_size; | |
157 | default: | |
158 | break; | |
159 | } | |
160 | ||
161 | return 0; | |
162 | } | |
163 | ||
84f97cb6 AS |
164 | #define get_DW_EH_PE_signed(encoding) (((encoding) & DW_EH_PE_signed) != 0) |
165 | ||
9e2a4898 JJ |
166 | /* Read a width sized value from memory. */ |
167 | ||
168 | static bfd_vma | |
c39a58e6 | 169 | read_value (bfd *abfd, bfd_byte *buf, int width, int is_signed) |
9e2a4898 JJ |
170 | { |
171 | bfd_vma value; | |
172 | ||
173 | switch (width) | |
174 | { | |
84f97cb6 AS |
175 | case 2: |
176 | if (is_signed) | |
177 | value = bfd_get_signed_16 (abfd, buf); | |
178 | else | |
179 | value = bfd_get_16 (abfd, buf); | |
180 | break; | |
181 | case 4: | |
182 | if (is_signed) | |
183 | value = bfd_get_signed_32 (abfd, buf); | |
184 | else | |
185 | value = bfd_get_32 (abfd, buf); | |
186 | break; | |
187 | case 8: | |
188 | if (is_signed) | |
189 | value = bfd_get_signed_64 (abfd, buf); | |
190 | else | |
191 | value = bfd_get_64 (abfd, buf); | |
192 | break; | |
193 | default: | |
194 | BFD_FAIL (); | |
195 | return 0; | |
9e2a4898 JJ |
196 | } |
197 | ||
198 | return value; | |
199 | } | |
b34976b6 | 200 | |
9e2a4898 JJ |
201 | /* Store a width sized value to memory. */ |
202 | ||
203 | static void | |
c39a58e6 | 204 | write_value (bfd *abfd, bfd_byte *buf, bfd_vma value, int width) |
9e2a4898 JJ |
205 | { |
206 | switch (width) | |
207 | { | |
208 | case 2: bfd_put_16 (abfd, value, buf); break; | |
209 | case 4: bfd_put_32 (abfd, value, buf); break; | |
210 | case 8: bfd_put_64 (abfd, value, buf); break; | |
211 | default: BFD_FAIL (); | |
212 | } | |
213 | } | |
214 | ||
bce613b9 | 215 | /* Return one if C1 and C2 CIEs can be merged. */ |
65765700 | 216 | |
bce613b9 JJ |
217 | static int |
218 | cie_eq (const void *e1, const void *e2) | |
65765700 | 219 | { |
a50b1753 NC |
220 | const struct cie *c1 = (const struct cie *) e1; |
221 | const struct cie *c2 = (const struct cie *) e2; | |
bce613b9 JJ |
222 | |
223 | if (c1->hash == c2->hash | |
224 | && c1->length == c2->length | |
65765700 | 225 | && c1->version == c2->version |
f137a54e | 226 | && c1->local_personality == c2->local_personality |
65765700 JJ |
227 | && strcmp (c1->augmentation, c2->augmentation) == 0 |
228 | && strcmp (c1->augmentation, "eh") != 0 | |
229 | && c1->code_align == c2->code_align | |
230 | && c1->data_align == c2->data_align | |
231 | && c1->ra_column == c2->ra_column | |
232 | && c1->augmentation_size == c2->augmentation_size | |
f137a54e AM |
233 | && memcmp (&c1->personality, &c2->personality, |
234 | sizeof (c1->personality)) == 0 | |
bce613b9 | 235 | && c1->output_sec == c2->output_sec |
65765700 JJ |
236 | && c1->per_encoding == c2->per_encoding |
237 | && c1->lsda_encoding == c2->lsda_encoding | |
238 | && c1->fde_encoding == c2->fde_encoding | |
c39a58e6 | 239 | && c1->initial_insn_length == c2->initial_insn_length |
99d190fa | 240 | && c1->initial_insn_length <= sizeof (c1->initial_instructions) |
65765700 JJ |
241 | && memcmp (c1->initial_instructions, |
242 | c2->initial_instructions, | |
243 | c1->initial_insn_length) == 0) | |
bce613b9 | 244 | return 1; |
65765700 | 245 | |
bce613b9 JJ |
246 | return 0; |
247 | } | |
248 | ||
249 | static hashval_t | |
250 | cie_hash (const void *e) | |
251 | { | |
a50b1753 | 252 | const struct cie *c = (const struct cie *) e; |
bce613b9 JJ |
253 | return c->hash; |
254 | } | |
255 | ||
256 | static hashval_t | |
257 | cie_compute_hash (struct cie *c) | |
258 | { | |
259 | hashval_t h = 0; | |
99d190fa | 260 | size_t len; |
bce613b9 JJ |
261 | h = iterative_hash_object (c->length, h); |
262 | h = iterative_hash_object (c->version, h); | |
263 | h = iterative_hash (c->augmentation, strlen (c->augmentation) + 1, h); | |
264 | h = iterative_hash_object (c->code_align, h); | |
265 | h = iterative_hash_object (c->data_align, h); | |
266 | h = iterative_hash_object (c->ra_column, h); | |
267 | h = iterative_hash_object (c->augmentation_size, h); | |
268 | h = iterative_hash_object (c->personality, h); | |
269 | h = iterative_hash_object (c->output_sec, h); | |
270 | h = iterative_hash_object (c->per_encoding, h); | |
271 | h = iterative_hash_object (c->lsda_encoding, h); | |
272 | h = iterative_hash_object (c->fde_encoding, h); | |
273 | h = iterative_hash_object (c->initial_insn_length, h); | |
99d190fa AM |
274 | len = c->initial_insn_length; |
275 | if (len > sizeof (c->initial_instructions)) | |
276 | len = sizeof (c->initial_instructions); | |
277 | h = iterative_hash (c->initial_instructions, len, h); | |
bce613b9 JJ |
278 | c->hash = h; |
279 | return h; | |
65765700 JJ |
280 | } |
281 | ||
353057a5 RS |
282 | /* Return the number of extra bytes that we'll be inserting into |
283 | ENTRY's augmentation string. */ | |
284 | ||
285 | static INLINE unsigned int | |
286 | extra_augmentation_string_bytes (struct eh_cie_fde *entry) | |
287 | { | |
288 | unsigned int size = 0; | |
289 | if (entry->cie) | |
290 | { | |
291 | if (entry->add_augmentation_size) | |
292 | size++; | |
6b2cc140 | 293 | if (entry->u.cie.add_fde_encoding) |
353057a5 RS |
294 | size++; |
295 | } | |
296 | return size; | |
297 | } | |
298 | ||
299 | /* Likewise ENTRY's augmentation data. */ | |
300 | ||
301 | static INLINE unsigned int | |
302 | extra_augmentation_data_bytes (struct eh_cie_fde *entry) | |
303 | { | |
304 | unsigned int size = 0; | |
6b2cc140 RS |
305 | if (entry->add_augmentation_size) |
306 | size++; | |
307 | if (entry->cie && entry->u.cie.add_fde_encoding) | |
308 | size++; | |
353057a5 RS |
309 | return size; |
310 | } | |
311 | ||
312 | /* Return the size that ENTRY will have in the output. ALIGNMENT is the | |
313 | required alignment of ENTRY in bytes. */ | |
314 | ||
315 | static unsigned int | |
316 | size_of_output_cie_fde (struct eh_cie_fde *entry, unsigned int alignment) | |
317 | { | |
318 | if (entry->removed) | |
319 | return 0; | |
320 | if (entry->size == 4) | |
321 | return 4; | |
322 | return (entry->size | |
323 | + extra_augmentation_string_bytes (entry) | |
324 | + extra_augmentation_data_bytes (entry) | |
325 | + alignment - 1) & -alignment; | |
326 | } | |
327 | ||
dcf507a6 RS |
328 | /* Assume that the bytes between *ITER and END are CFA instructions. |
329 | Try to move *ITER past the first instruction and return true on | |
330 | success. ENCODED_PTR_WIDTH gives the width of pointer entries. */ | |
331 | ||
332 | static bfd_boolean | |
333 | skip_cfa_op (bfd_byte **iter, bfd_byte *end, unsigned int encoded_ptr_width) | |
334 | { | |
335 | bfd_byte op; | |
336 | bfd_vma length; | |
337 | ||
338 | if (!read_byte (iter, end, &op)) | |
339 | return FALSE; | |
340 | ||
ac685e6a | 341 | switch (op & 0xc0 ? op & 0xc0 : op) |
dcf507a6 RS |
342 | { |
343 | case DW_CFA_nop: | |
344 | case DW_CFA_advance_loc: | |
345 | case DW_CFA_restore: | |
ac685e6a JJ |
346 | case DW_CFA_remember_state: |
347 | case DW_CFA_restore_state: | |
348 | case DW_CFA_GNU_window_save: | |
dcf507a6 RS |
349 | /* No arguments. */ |
350 | return TRUE; | |
351 | ||
352 | case DW_CFA_offset: | |
353 | case DW_CFA_restore_extended: | |
354 | case DW_CFA_undefined: | |
355 | case DW_CFA_same_value: | |
356 | case DW_CFA_def_cfa_register: | |
357 | case DW_CFA_def_cfa_offset: | |
358 | case DW_CFA_def_cfa_offset_sf: | |
359 | case DW_CFA_GNU_args_size: | |
360 | /* One leb128 argument. */ | |
361 | return skip_leb128 (iter, end); | |
362 | ||
ac685e6a JJ |
363 | case DW_CFA_val_offset: |
364 | case DW_CFA_val_offset_sf: | |
dcf507a6 RS |
365 | case DW_CFA_offset_extended: |
366 | case DW_CFA_register: | |
367 | case DW_CFA_def_cfa: | |
368 | case DW_CFA_offset_extended_sf: | |
369 | case DW_CFA_GNU_negative_offset_extended: | |
370 | case DW_CFA_def_cfa_sf: | |
371 | /* Two leb128 arguments. */ | |
372 | return (skip_leb128 (iter, end) | |
373 | && skip_leb128 (iter, end)); | |
374 | ||
375 | case DW_CFA_def_cfa_expression: | |
376 | /* A variable-length argument. */ | |
377 | return (read_uleb128 (iter, end, &length) | |
378 | && skip_bytes (iter, end, length)); | |
379 | ||
380 | case DW_CFA_expression: | |
ac685e6a | 381 | case DW_CFA_val_expression: |
dcf507a6 RS |
382 | /* A leb128 followed by a variable-length argument. */ |
383 | return (skip_leb128 (iter, end) | |
384 | && read_uleb128 (iter, end, &length) | |
385 | && skip_bytes (iter, end, length)); | |
386 | ||
387 | case DW_CFA_set_loc: | |
388 | return skip_bytes (iter, end, encoded_ptr_width); | |
389 | ||
390 | case DW_CFA_advance_loc1: | |
391 | return skip_bytes (iter, end, 1); | |
392 | ||
393 | case DW_CFA_advance_loc2: | |
394 | return skip_bytes (iter, end, 2); | |
395 | ||
396 | case DW_CFA_advance_loc4: | |
397 | return skip_bytes (iter, end, 4); | |
398 | ||
399 | case DW_CFA_MIPS_advance_loc8: | |
400 | return skip_bytes (iter, end, 8); | |
401 | ||
402 | default: | |
403 | return FALSE; | |
404 | } | |
405 | } | |
406 | ||
407 | /* Try to interpret the bytes between BUF and END as CFA instructions. | |
408 | If every byte makes sense, return a pointer to the first DW_CFA_nop | |
409 | padding byte, or END if there is no padding. Return null otherwise. | |
410 | ENCODED_PTR_WIDTH is as for skip_cfa_op. */ | |
411 | ||
412 | static bfd_byte * | |
ac685e6a JJ |
413 | skip_non_nops (bfd_byte *buf, bfd_byte *end, unsigned int encoded_ptr_width, |
414 | unsigned int *set_loc_count) | |
dcf507a6 RS |
415 | { |
416 | bfd_byte *last; | |
417 | ||
418 | last = buf; | |
419 | while (buf < end) | |
420 | if (*buf == DW_CFA_nop) | |
421 | buf++; | |
422 | else | |
423 | { | |
ac685e6a JJ |
424 | if (*buf == DW_CFA_set_loc) |
425 | ++*set_loc_count; | |
dcf507a6 RS |
426 | if (!skip_cfa_op (&buf, end, encoded_ptr_width)) |
427 | return 0; | |
428 | last = buf; | |
429 | } | |
430 | return last; | |
431 | } | |
432 | ||
30af5962 RS |
433 | /* Convert absolute encoding ENCODING into PC-relative form. |
434 | SIZE is the size of a pointer. */ | |
435 | ||
436 | static unsigned char | |
437 | make_pc_relative (unsigned char encoding, unsigned int ptr_size) | |
438 | { | |
439 | if ((encoding & 0x7f) == DW_EH_PE_absptr) | |
440 | switch (ptr_size) | |
441 | { | |
442 | case 2: | |
443 | encoding |= DW_EH_PE_sdata2; | |
444 | break; | |
445 | case 4: | |
446 | encoding |= DW_EH_PE_sdata4; | |
447 | break; | |
448 | case 8: | |
449 | encoding |= DW_EH_PE_sdata8; | |
450 | break; | |
451 | } | |
452 | return encoding | DW_EH_PE_pcrel; | |
453 | } | |
454 | ||
ca92cecb RS |
455 | /* Called before calling _bfd_elf_parse_eh_frame on every input bfd's |
456 | .eh_frame section. */ | |
65765700 | 457 | |
ca92cecb RS |
458 | void |
459 | _bfd_elf_begin_eh_frame_parsing (struct bfd_link_info *info) | |
460 | { | |
461 | struct eh_frame_hdr_info *hdr_info; | |
462 | ||
463 | hdr_info = &elf_hash_table (info)->eh_info; | |
184d07da | 464 | hdr_info->merge_cies = !info->relocatable; |
ca92cecb RS |
465 | } |
466 | ||
467 | /* Try to parse .eh_frame section SEC, which belongs to ABFD. Store the | |
468 | information in the section's sec_info field on success. COOKIE | |
469 | describes the relocations in SEC. */ | |
470 | ||
471 | void | |
472 | _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, | |
473 | asection *sec, struct elf_reloc_cookie *cookie) | |
65765700 | 474 | { |
acfe5567 RS |
475 | #define REQUIRE(COND) \ |
476 | do \ | |
477 | if (!(COND)) \ | |
478 | goto free_no_table; \ | |
479 | while (0) | |
480 | ||
ca92cecb | 481 | bfd_byte *ehbuf = NULL, *buf, *end; |
bce613b9 | 482 | bfd_byte *last_fde; |
ca92cecb | 483 | struct eh_cie_fde *this_inf; |
bce613b9 | 484 | unsigned int hdr_length, hdr_id; |
184d07da RS |
485 | unsigned int cie_count; |
486 | struct cie *cie, *local_cies = NULL; | |
126495ed | 487 | struct elf_link_hash_table *htab; |
65765700 | 488 | struct eh_frame_hdr_info *hdr_info; |
68f69152 | 489 | struct eh_frame_sec_info *sec_info = NULL; |
65765700 | 490 | unsigned int ptr_size; |
ca92cecb RS |
491 | unsigned int num_cies; |
492 | unsigned int num_entries; | |
9d0a14d3 | 493 | elf_gc_mark_hook_fn gc_mark_hook; |
ca92cecb RS |
494 | |
495 | htab = elf_hash_table (info); | |
496 | hdr_info = &htab->eh_info; | |
497 | if (hdr_info->parsed_eh_frames) | |
498 | return; | |
65765700 | 499 | |
4d16d575 | 500 | if (sec->size == 0 |
dbaa2011 | 501 | || sec->sec_info_type != SEC_INFO_TYPE_NONE) |
65765700 JJ |
502 | { |
503 | /* This file does not contain .eh_frame information. */ | |
ca92cecb | 504 | return; |
65765700 JJ |
505 | } |
506 | ||
e460dd0d | 507 | if (bfd_is_abs_section (sec->output_section)) |
65765700 JJ |
508 | { |
509 | /* At least one of the sections is being discarded from the | |
3472e2e9 | 510 | link, so we should just ignore them. */ |
ca92cecb | 511 | return; |
65765700 JJ |
512 | } |
513 | ||
514 | /* Read the frame unwind information from abfd. */ | |
515 | ||
acfe5567 | 516 | REQUIRE (bfd_malloc_and_get_section (abfd, sec, &ehbuf)); |
68f69152 | 517 | |
eea6121a | 518 | if (sec->size >= 4 |
65765700 JJ |
519 | && bfd_get_32 (abfd, ehbuf) == 0 |
520 | && cookie->rel == cookie->relend) | |
521 | { | |
522 | /* Empty .eh_frame section. */ | |
523 | free (ehbuf); | |
ca92cecb | 524 | return; |
65765700 JJ |
525 | } |
526 | ||
65765700 JJ |
527 | /* If .eh_frame section size doesn't fit into int, we cannot handle |
528 | it (it would need to use 64-bit .eh_frame format anyway). */ | |
acfe5567 | 529 | REQUIRE (sec->size == (unsigned int) sec->size); |
65765700 | 530 | |
8c946ed5 RS |
531 | ptr_size = (get_elf_backend_data (abfd) |
532 | ->elf_backend_eh_frame_address_size (abfd, sec)); | |
533 | REQUIRE (ptr_size != 0); | |
534 | ||
ca92cecb RS |
535 | /* Go through the section contents and work out how many FDEs and |
536 | CIEs there are. */ | |
65765700 | 537 | buf = ehbuf; |
ca92cecb RS |
538 | end = ehbuf + sec->size; |
539 | num_cies = 0; | |
540 | num_entries = 0; | |
541 | while (buf != end) | |
542 | { | |
543 | num_entries++; | |
544 | ||
545 | /* Read the length of the entry. */ | |
546 | REQUIRE (skip_bytes (&buf, end, 4)); | |
547 | hdr_length = bfd_get_32 (abfd, buf - 4); | |
548 | ||
549 | /* 64-bit .eh_frame is not supported. */ | |
550 | REQUIRE (hdr_length != 0xffffffff); | |
551 | if (hdr_length == 0) | |
552 | break; | |
553 | ||
554 | REQUIRE (skip_bytes (&buf, end, 4)); | |
555 | hdr_id = bfd_get_32 (abfd, buf - 4); | |
556 | if (hdr_id == 0) | |
557 | num_cies++; | |
558 | ||
559 | REQUIRE (skip_bytes (&buf, end, hdr_length - 4)); | |
560 | } | |
561 | ||
a50b1753 NC |
562 | sec_info = (struct eh_frame_sec_info *) |
563 | bfd_zmalloc (sizeof (struct eh_frame_sec_info) | |
564 | + (num_entries - 1) * sizeof (struct eh_cie_fde)); | |
acfe5567 | 565 | REQUIRE (sec_info); |
eea6121a | 566 | |
184d07da | 567 | /* We need to have a "struct cie" for each CIE in this section. */ |
a50b1753 | 568 | local_cies = (struct cie *) bfd_zmalloc (num_cies * sizeof (*local_cies)); |
184d07da | 569 | REQUIRE (local_cies); |
65765700 | 570 | |
5dabe785 | 571 | /* FIXME: octets_per_byte. */ |
65765700 | 572 | #define ENSURE_NO_RELOCS(buf) \ |
acfe5567 RS |
573 | REQUIRE (!(cookie->rel < cookie->relend \ |
574 | && (cookie->rel->r_offset \ | |
575 | < (bfd_size_type) ((buf) - ehbuf)) \ | |
576 | && cookie->rel->r_info != 0)) | |
65765700 | 577 | |
5dabe785 | 578 | /* FIXME: octets_per_byte. */ |
65765700 JJ |
579 | #define SKIP_RELOCS(buf) \ |
580 | while (cookie->rel < cookie->relend \ | |
3472e2e9 | 581 | && (cookie->rel->r_offset \ |
65765700 JJ |
582 | < (bfd_size_type) ((buf) - ehbuf))) \ |
583 | cookie->rel++ | |
584 | ||
5dabe785 | 585 | /* FIXME: octets_per_byte. */ |
65765700 JJ |
586 | #define GET_RELOC(buf) \ |
587 | ((cookie->rel < cookie->relend \ | |
588 | && (cookie->rel->r_offset \ | |
3472e2e9 | 589 | == (bfd_size_type) ((buf) - ehbuf))) \ |
65765700 JJ |
590 | ? cookie->rel : NULL) |
591 | ||
ca92cecb | 592 | buf = ehbuf; |
184d07da | 593 | cie_count = 0; |
9d0a14d3 | 594 | gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook; |
ca92cecb | 595 | while ((bfd_size_type) (buf - ehbuf) != sec->size) |
65765700 | 596 | { |
f075ee0c | 597 | char *aug; |
ca92cecb | 598 | bfd_byte *start, *insns, *insns_end; |
2c42be65 | 599 | bfd_size_type length; |
ac685e6a | 600 | unsigned int set_loc_count; |
65765700 | 601 | |
fda3ecf2 | 602 | this_inf = sec_info->entry + sec_info->count; |
65765700 | 603 | last_fde = buf; |
bce613b9 | 604 | |
bce613b9 JJ |
605 | /* Read the length of the entry. */ |
606 | REQUIRE (skip_bytes (&buf, ehbuf + sec->size, 4)); | |
607 | hdr_length = bfd_get_32 (abfd, buf - 4); | |
acfe5567 | 608 | |
bce613b9 JJ |
609 | /* The CIE/FDE must be fully contained in this input section. */ |
610 | REQUIRE ((bfd_size_type) (buf - ehbuf) + hdr_length <= sec->size); | |
611 | end = buf + hdr_length; | |
65765700 | 612 | |
bce613b9 JJ |
613 | this_inf->offset = last_fde - ehbuf; |
614 | this_inf->size = 4 + hdr_length; | |
155eaaa0 | 615 | this_inf->reloc_index = cookie->rel - cookie->rels; |
bce613b9 JJ |
616 | |
617 | if (hdr_length == 0) | |
618 | { | |
619 | /* A zero-length CIE should only be found at the end of | |
620 | the section. */ | |
621 | REQUIRE ((bfd_size_type) (buf - ehbuf) == sec->size); | |
622 | ENSURE_NO_RELOCS (buf); | |
623 | sec_info->count++; | |
624 | break; | |
65765700 JJ |
625 | } |
626 | ||
bce613b9 JJ |
627 | REQUIRE (skip_bytes (&buf, end, 4)); |
628 | hdr_id = bfd_get_32 (abfd, buf - 4); | |
629 | ||
630 | if (hdr_id == 0) | |
65765700 JJ |
631 | { |
632 | unsigned int initial_insn_length; | |
633 | ||
634 | /* CIE */ | |
bce613b9 JJ |
635 | this_inf->cie = 1; |
636 | ||
184d07da RS |
637 | /* Point CIE to one of the section-local cie structures. */ |
638 | cie = local_cies + cie_count++; | |
639 | ||
ca92cecb | 640 | cie->cie_inf = this_inf; |
bce613b9 | 641 | cie->length = hdr_length; |
ca92cecb | 642 | cie->output_sec = sec->output_section; |
ac685e6a | 643 | start = buf; |
bce613b9 | 644 | REQUIRE (read_byte (&buf, end, &cie->version)); |
65765700 JJ |
645 | |
646 | /* Cannot handle unknown versions. */ | |
604282a7 JJ |
647 | REQUIRE (cie->version == 1 |
648 | || cie->version == 3 | |
649 | || cie->version == 4); | |
bce613b9 | 650 | REQUIRE (strlen ((char *) buf) < sizeof (cie->augmentation)); |
65765700 | 651 | |
bce613b9 | 652 | strcpy (cie->augmentation, (char *) buf); |
f075ee0c | 653 | buf = (bfd_byte *) strchr ((char *) buf, '\0') + 1; |
65765700 JJ |
654 | ENSURE_NO_RELOCS (buf); |
655 | if (buf[0] == 'e' && buf[1] == 'h') | |
656 | { | |
657 | /* GCC < 3.0 .eh_frame CIE */ | |
658 | /* We cannot merge "eh" CIEs because __EXCEPTION_TABLE__ | |
659 | is private to each CIE, so we don't need it for anything. | |
660 | Just skip it. */ | |
2c42be65 | 661 | REQUIRE (skip_bytes (&buf, end, ptr_size)); |
65765700 JJ |
662 | SKIP_RELOCS (buf); |
663 | } | |
604282a7 JJ |
664 | if (cie->version >= 4) |
665 | { | |
666 | REQUIRE (buf + 1 < end); | |
667 | REQUIRE (buf[0] == ptr_size); | |
668 | REQUIRE (buf[1] == 0); | |
669 | buf += 2; | |
670 | } | |
bce613b9 JJ |
671 | REQUIRE (read_uleb128 (&buf, end, &cie->code_align)); |
672 | REQUIRE (read_sleb128 (&buf, end, &cie->data_align)); | |
673 | if (cie->version == 1) | |
2c42be65 RS |
674 | { |
675 | REQUIRE (buf < end); | |
bce613b9 | 676 | cie->ra_column = *buf++; |
2c42be65 | 677 | } |
0da76f83 | 678 | else |
bce613b9 | 679 | REQUIRE (read_uleb128 (&buf, end, &cie->ra_column)); |
65765700 | 680 | ENSURE_NO_RELOCS (buf); |
bce613b9 JJ |
681 | cie->lsda_encoding = DW_EH_PE_omit; |
682 | cie->fde_encoding = DW_EH_PE_omit; | |
683 | cie->per_encoding = DW_EH_PE_omit; | |
684 | aug = cie->augmentation; | |
65765700 JJ |
685 | if (aug[0] != 'e' || aug[1] != 'h') |
686 | { | |
687 | if (*aug == 'z') | |
688 | { | |
689 | aug++; | |
bce613b9 | 690 | REQUIRE (read_uleb128 (&buf, end, &cie->augmentation_size)); |
65765700 JJ |
691 | ENSURE_NO_RELOCS (buf); |
692 | } | |
693 | ||
694 | while (*aug != '\0') | |
695 | switch (*aug++) | |
696 | { | |
697 | case 'L': | |
bce613b9 | 698 | REQUIRE (read_byte (&buf, end, &cie->lsda_encoding)); |
65765700 | 699 | ENSURE_NO_RELOCS (buf); |
bce613b9 | 700 | REQUIRE (get_DW_EH_PE_width (cie->lsda_encoding, ptr_size)); |
65765700 JJ |
701 | break; |
702 | case 'R': | |
bce613b9 | 703 | REQUIRE (read_byte (&buf, end, &cie->fde_encoding)); |
65765700 | 704 | ENSURE_NO_RELOCS (buf); |
bce613b9 | 705 | REQUIRE (get_DW_EH_PE_width (cie->fde_encoding, ptr_size)); |
65765700 | 706 | break; |
63752a75 JJ |
707 | case 'S': |
708 | break; | |
65765700 JJ |
709 | case 'P': |
710 | { | |
711 | int per_width; | |
712 | ||
bce613b9 JJ |
713 | REQUIRE (read_byte (&buf, end, &cie->per_encoding)); |
714 | per_width = get_DW_EH_PE_width (cie->per_encoding, | |
65765700 | 715 | ptr_size); |
acfe5567 | 716 | REQUIRE (per_width); |
18e04883 | 717 | if ((cie->per_encoding & 0x70) == DW_EH_PE_aligned) |
2c42be65 RS |
718 | { |
719 | length = -(buf - ehbuf) & (per_width - 1); | |
720 | REQUIRE (skip_bytes (&buf, end, length)); | |
721 | } | |
18e04883 | 722 | this_inf->u.cie.personality_offset = buf - start; |
65765700 | 723 | ENSURE_NO_RELOCS (buf); |
f137a54e | 724 | /* Ensure we have a reloc here. */ |
184d07da RS |
725 | REQUIRE (GET_RELOC (buf)); |
726 | cie->personality.reloc_index | |
727 | = cookie->rel - cookie->rels; | |
728 | /* Cope with MIPS-style composite relocations. */ | |
729 | do | |
730 | cookie->rel++; | |
731 | while (GET_RELOC (buf) != NULL); | |
2c42be65 | 732 | REQUIRE (skip_bytes (&buf, end, per_width)); |
65765700 JJ |
733 | } |
734 | break; | |
735 | default: | |
736 | /* Unrecognized augmentation. Better bail out. */ | |
737 | goto free_no_table; | |
738 | } | |
739 | } | |
740 | ||
741 | /* For shared libraries, try to get rid of as many RELATIVE relocs | |
0bb2d96a | 742 | as possible. */ |
3472e2e9 | 743 | if (info->shared |
ec3391e7 AO |
744 | && (get_elf_backend_data (abfd) |
745 | ->elf_backend_can_make_relative_eh_frame | |
353057a5 RS |
746 | (abfd, info, sec))) |
747 | { | |
18e04883 | 748 | if ((cie->fde_encoding & 0x70) == DW_EH_PE_absptr) |
6b2cc140 | 749 | this_inf->make_relative = 1; |
353057a5 RS |
750 | /* If the CIE doesn't already have an 'R' entry, it's fairly |
751 | easy to add one, provided that there's no aligned data | |
752 | after the augmentation string. */ | |
bce613b9 | 753 | else if (cie->fde_encoding == DW_EH_PE_omit |
18e04883 | 754 | && (cie->per_encoding & 0x70) != DW_EH_PE_aligned) |
353057a5 | 755 | { |
bce613b9 | 756 | if (*cie->augmentation == 0) |
353057a5 | 757 | this_inf->add_augmentation_size = 1; |
6b2cc140 RS |
758 | this_inf->u.cie.add_fde_encoding = 1; |
759 | this_inf->make_relative = 1; | |
353057a5 | 760 | } |
65765700 | 761 | |
18e04883 RS |
762 | if ((cie->lsda_encoding & 0x70) == DW_EH_PE_absptr) |
763 | cie->can_make_lsda_relative = 1; | |
764 | } | |
9e2a4898 | 765 | |
65765700 JJ |
766 | /* If FDE encoding was not specified, it defaults to |
767 | DW_EH_absptr. */ | |
bce613b9 JJ |
768 | if (cie->fde_encoding == DW_EH_PE_omit) |
769 | cie->fde_encoding = DW_EH_PE_absptr; | |
65765700 | 770 | |
dcf507a6 | 771 | initial_insn_length = end - buf; |
99d190fa AM |
772 | cie->initial_insn_length = initial_insn_length; |
773 | memcpy (cie->initial_instructions, buf, | |
774 | initial_insn_length <= sizeof (cie->initial_instructions) | |
775 | ? initial_insn_length : sizeof (cie->initial_instructions)); | |
dcf507a6 | 776 | insns = buf; |
65765700 JJ |
777 | buf += initial_insn_length; |
778 | ENSURE_NO_RELOCS (buf); | |
ca92cecb | 779 | |
184d07da RS |
780 | if (hdr_info->merge_cies) |
781 | this_inf->u.cie.u.full_cie = cie; | |
6b2cc140 | 782 | this_inf->u.cie.per_encoding_relative |
ca92cecb | 783 | = (cie->per_encoding & 0x70) == DW_EH_PE_pcrel; |
65765700 JJ |
784 | } |
785 | else | |
786 | { | |
bce613b9 JJ |
787 | /* Find the corresponding CIE. */ |
788 | unsigned int cie_offset = this_inf->offset + 4 - hdr_id; | |
184d07da RS |
789 | for (cie = local_cies; cie < local_cies + cie_count; cie++) |
790 | if (cie_offset == cie->cie_inf->offset) | |
bce613b9 JJ |
791 | break; |
792 | ||
793 | /* Ensure this FDE references one of the CIEs in this input | |
794 | section. */ | |
184d07da RS |
795 | REQUIRE (cie != local_cies + cie_count); |
796 | this_inf->u.fde.cie_inf = cie->cie_inf; | |
797 | this_inf->make_relative = cie->cie_inf->make_relative; | |
6b2cc140 | 798 | this_inf->add_augmentation_size |
184d07da | 799 | = cie->cie_inf->add_augmentation_size; |
65765700 JJ |
800 | |
801 | ENSURE_NO_RELOCS (buf); | |
e41b3a13 | 802 | if ((sec->flags & SEC_LINKER_CREATED) == 0 || cookie->rels != NULL) |
2a7b2e88 | 803 | { |
e41b3a13 JJ |
804 | asection *rsec; |
805 | ||
806 | REQUIRE (GET_RELOC (buf)); | |
807 | ||
808 | /* Chain together the FDEs for each section. */ | |
809 | rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie); | |
810 | /* RSEC will be NULL if FDE was cleared out as it was belonging to | |
811 | a discarded SHT_GROUP. */ | |
812 | if (rsec) | |
813 | { | |
814 | REQUIRE (rsec->owner == abfd); | |
815 | this_inf->u.fde.next_for_section = elf_fde_list (rsec); | |
816 | elf_fde_list (rsec) = this_inf; | |
817 | } | |
2a7b2e88 | 818 | } |
9d0a14d3 | 819 | |
2c42be65 RS |
820 | /* Skip the initial location and address range. */ |
821 | start = buf; | |
bce613b9 | 822 | length = get_DW_EH_PE_width (cie->fde_encoding, ptr_size); |
2c42be65 RS |
823 | REQUIRE (skip_bytes (&buf, end, 2 * length)); |
824 | ||
825 | /* Skip the augmentation size, if present. */ | |
bce613b9 | 826 | if (cie->augmentation[0] == 'z') |
dcf507a6 RS |
827 | REQUIRE (read_uleb128 (&buf, end, &length)); |
828 | else | |
829 | length = 0; | |
2c42be65 RS |
830 | |
831 | /* Of the supported augmentation characters above, only 'L' | |
832 | adds augmentation data to the FDE. This code would need to | |
833 | be adjusted if any future augmentations do the same thing. */ | |
bce613b9 | 834 | if (cie->lsda_encoding != DW_EH_PE_omit) |
dcf507a6 | 835 | { |
9f4b847e RS |
836 | SKIP_RELOCS (buf); |
837 | if (cie->can_make_lsda_relative && GET_RELOC (buf)) | |
838 | cie->cie_inf->u.cie.make_lsda_relative = 1; | |
dcf507a6 RS |
839 | this_inf->lsda_offset = buf - start; |
840 | /* If there's no 'z' augmentation, we don't know where the | |
841 | CFA insns begin. Assume no padding. */ | |
bce613b9 | 842 | if (cie->augmentation[0] != 'z') |
dcf507a6 RS |
843 | length = end - buf; |
844 | } | |
845 | ||
846 | /* Skip over the augmentation data. */ | |
847 | REQUIRE (skip_bytes (&buf, end, length)); | |
848 | insns = buf; | |
9e2a4898 | 849 | |
bce613b9 | 850 | buf = last_fde + 4 + hdr_length; |
2a7b2e88 | 851 | |
273f4430 JK |
852 | /* For NULL RSEC (cleared FDE belonging to a discarded section) |
853 | the relocations are commonly cleared. We do not sanity check if | |
854 | all these relocations are cleared as (1) relocations to | |
855 | .gcc_except_table will remain uncleared (they will get dropped | |
856 | with the drop of this unused FDE) and (2) BFD already safely drops | |
857 | relocations of any type to .eh_frame by | |
858 | elf_section_ignore_discarded_relocs. | |
859 | TODO: The .gcc_except_table entries should be also filtered as | |
860 | .eh_frame entries; or GCC could rather use COMDAT for them. */ | |
861 | SKIP_RELOCS (buf); | |
65765700 JJ |
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 |
18e04883 | 884 | && ((cie->fde_encoding & 0x70) == DW_EH_PE_pcrel |
6b2cc140 | 885 | || this_inf->make_relative)) |
ac685e6a JJ |
886 | { |
887 | unsigned int cnt; | |
888 | bfd_byte *p; | |
889 | ||
a50b1753 NC |
890 | this_inf->set_loc = (unsigned int *) |
891 | bfd_malloc ((set_loc_count + 1) * sizeof (unsigned int)); | |
ac685e6a JJ |
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 | |
ca92cecb | 904 | this_inf->removed = 1; |
bce613b9 JJ |
905 | this_inf->fde_encoding = cie->fde_encoding; |
906 | this_inf->lsda_encoding = cie->lsda_encoding; | |
65765700 JJ |
907 | sec_info->count++; |
908 | } | |
ca92cecb | 909 | BFD_ASSERT (sec_info->count == num_entries); |
184d07da | 910 | BFD_ASSERT (cie_count == num_cies); |
65765700 JJ |
911 | |
912 | elf_section_data (sec)->sec_info = sec_info; | |
dbaa2011 | 913 | sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME; |
184d07da RS |
914 | if (hdr_info->merge_cies) |
915 | { | |
916 | sec_info->cies = local_cies; | |
917 | local_cies = NULL; | |
918 | } | |
ca92cecb | 919 | goto success; |
65765700 | 920 | |
ca92cecb RS |
921 | free_no_table: |
922 | (*info->callbacks->einfo) | |
923 | (_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"), | |
924 | abfd, sec); | |
925 | hdr_info->table = FALSE; | |
926 | if (sec_info) | |
927 | free (sec_info); | |
928 | success: | |
929 | if (ehbuf) | |
930 | free (ehbuf); | |
ca92cecb RS |
931 | if (local_cies) |
932 | free (local_cies); | |
933 | #undef REQUIRE | |
934 | } | |
bce613b9 | 935 | |
ca92cecb RS |
936 | /* Finish a pass over all .eh_frame sections. */ |
937 | ||
938 | void | |
939 | _bfd_elf_end_eh_frame_parsing (struct bfd_link_info *info) | |
940 | { | |
941 | struct eh_frame_hdr_info *hdr_info; | |
942 | ||
943 | hdr_info = &elf_hash_table (info)->eh_info; | |
ca92cecb RS |
944 | hdr_info->parsed_eh_frames = TRUE; |
945 | } | |
bce613b9 | 946 | |
9d0a14d3 RS |
947 | /* Mark all relocations against CIE or FDE ENT, which occurs in |
948 | .eh_frame section SEC. COOKIE describes the relocations in SEC; | |
949 | its "rel" field can be changed freely. */ | |
950 | ||
951 | static bfd_boolean | |
952 | mark_entry (struct bfd_link_info *info, asection *sec, | |
953 | struct eh_cie_fde *ent, elf_gc_mark_hook_fn gc_mark_hook, | |
954 | struct elf_reloc_cookie *cookie) | |
955 | { | |
5dabe785 | 956 | /* FIXME: octets_per_byte. */ |
9d0a14d3 RS |
957 | for (cookie->rel = cookie->rels + ent->reloc_index; |
958 | cookie->rel < cookie->relend | |
959 | && cookie->rel->r_offset < ent->offset + ent->size; | |
960 | cookie->rel++) | |
961 | if (!_bfd_elf_gc_mark_reloc (info, sec, gc_mark_hook, cookie)) | |
962 | return FALSE; | |
963 | ||
964 | return TRUE; | |
965 | } | |
966 | ||
967 | /* Mark all the relocations against FDEs that relate to code in input | |
968 | section SEC. The FDEs belong to .eh_frame section EH_FRAME, whose | |
969 | relocations are described by COOKIE. */ | |
970 | ||
971 | bfd_boolean | |
972 | _bfd_elf_gc_mark_fdes (struct bfd_link_info *info, asection *sec, | |
973 | asection *eh_frame, elf_gc_mark_hook_fn gc_mark_hook, | |
974 | struct elf_reloc_cookie *cookie) | |
975 | { | |
184d07da | 976 | struct eh_cie_fde *fde, *cie; |
9d0a14d3 RS |
977 | |
978 | for (fde = elf_fde_list (sec); fde; fde = fde->u.fde.next_for_section) | |
979 | { | |
980 | if (!mark_entry (info, eh_frame, fde, gc_mark_hook, cookie)) | |
981 | return FALSE; | |
982 | ||
983 | /* At this stage, all cie_inf fields point to local CIEs, so we | |
984 | can use the same cookie to refer to them. */ | |
985 | cie = fde->u.fde.cie_inf; | |
184d07da | 986 | if (!cie->u.cie.gc_mark) |
9d0a14d3 | 987 | { |
184d07da | 988 | cie->u.cie.gc_mark = 1; |
9d0a14d3 RS |
989 | if (!mark_entry (info, eh_frame, cie, gc_mark_hook, cookie)) |
990 | return FALSE; | |
991 | } | |
992 | } | |
993 | return TRUE; | |
994 | } | |
995 | ||
184d07da RS |
996 | /* Input section SEC of ABFD is an .eh_frame section that contains the |
997 | CIE described by CIE_INF. Return a version of CIE_INF that is going | |
998 | to be kept in the output, adding CIE_INF to the output if necessary. | |
999 | ||
1000 | HDR_INFO is the .eh_frame_hdr information and COOKIE describes the | |
1001 | relocations in REL. */ | |
1002 | ||
1003 | static struct eh_cie_fde * | |
18e04883 | 1004 | find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec, |
184d07da RS |
1005 | struct eh_frame_hdr_info *hdr_info, |
1006 | struct elf_reloc_cookie *cookie, | |
1007 | struct eh_cie_fde *cie_inf) | |
1008 | { | |
1009 | unsigned long r_symndx; | |
1010 | struct cie *cie, *new_cie; | |
1011 | Elf_Internal_Rela *rel; | |
1012 | void **loc; | |
1013 | ||
1014 | /* Use CIE_INF if we have already decided to keep it. */ | |
1015 | if (!cie_inf->removed) | |
1016 | return cie_inf; | |
1017 | ||
1018 | /* If we have merged CIE_INF with another CIE, use that CIE instead. */ | |
1019 | if (cie_inf->u.cie.merged) | |
1020 | return cie_inf->u.cie.u.merged_with; | |
1021 | ||
1022 | cie = cie_inf->u.cie.u.full_cie; | |
1023 | ||
1024 | /* Assume we will need to keep CIE_INF. */ | |
1025 | cie_inf->removed = 0; | |
1026 | cie_inf->u.cie.u.sec = sec; | |
1027 | ||
1028 | /* If we are not merging CIEs, use CIE_INF. */ | |
1029 | if (cie == NULL) | |
1030 | return cie_inf; | |
1031 | ||
1032 | if (cie->per_encoding != DW_EH_PE_omit) | |
1033 | { | |
18e04883 RS |
1034 | bfd_boolean per_binds_local; |
1035 | ||
5087d529 AM |
1036 | /* Work out the address of personality routine, or at least |
1037 | enough info that we could calculate the address had we made a | |
1038 | final section layout. The symbol on the reloc is enough, | |
1039 | either the hash for a global, or (bfd id, index) pair for a | |
1040 | local. The assumption here is that no one uses addends on | |
1041 | the reloc. */ | |
184d07da RS |
1042 | rel = cookie->rels + cie->personality.reloc_index; |
1043 | memset (&cie->personality, 0, sizeof (cie->personality)); | |
1044 | #ifdef BFD64 | |
1045 | if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64) | |
1046 | r_symndx = ELF64_R_SYM (rel->r_info); | |
1047 | else | |
1048 | #endif | |
1049 | r_symndx = ELF32_R_SYM (rel->r_info); | |
1050 | if (r_symndx >= cookie->locsymcount | |
1051 | || ELF_ST_BIND (cookie->locsyms[r_symndx].st_info) != STB_LOCAL) | |
1052 | { | |
1053 | struct elf_link_hash_entry *h; | |
1054 | ||
1055 | r_symndx -= cookie->extsymoff; | |
1056 | h = cookie->sym_hashes[r_symndx]; | |
1057 | ||
1058 | while (h->root.type == bfd_link_hash_indirect | |
1059 | || h->root.type == bfd_link_hash_warning) | |
1060 | h = (struct elf_link_hash_entry *) h->root.u.i.link; | |
1061 | ||
1062 | cie->personality.h = h; | |
18e04883 | 1063 | per_binds_local = SYMBOL_REFERENCES_LOCAL (info, h); |
184d07da RS |
1064 | } |
1065 | else | |
1066 | { | |
1067 | Elf_Internal_Sym *sym; | |
1068 | asection *sym_sec; | |
1069 | ||
1070 | sym = &cookie->locsyms[r_symndx]; | |
1071 | sym_sec = bfd_section_from_elf_index (abfd, sym->st_shndx); | |
1072 | if (sym_sec == NULL) | |
1073 | return cie_inf; | |
1074 | ||
1075 | if (sym_sec->kept_section != NULL) | |
1076 | sym_sec = sym_sec->kept_section; | |
1077 | if (sym_sec->output_section == NULL) | |
1078 | return cie_inf; | |
1079 | ||
1080 | cie->local_personality = 1; | |
5087d529 AM |
1081 | cie->personality.sym.bfd_id = abfd->id; |
1082 | cie->personality.sym.index = r_symndx; | |
18e04883 RS |
1083 | per_binds_local = TRUE; |
1084 | } | |
1085 | ||
1086 | if (per_binds_local | |
1087 | && info->shared | |
1088 | && (cie->per_encoding & 0x70) == DW_EH_PE_absptr | |
1089 | && (get_elf_backend_data (abfd) | |
1090 | ->elf_backend_can_make_relative_eh_frame (abfd, info, sec))) | |
1091 | { | |
1092 | cie_inf->u.cie.make_per_encoding_relative = 1; | |
1093 | cie_inf->u.cie.per_encoding_relative = 1; | |
184d07da RS |
1094 | } |
1095 | } | |
1096 | ||
1097 | /* See if we can merge this CIE with an earlier one. */ | |
1098 | cie->output_sec = sec->output_section; | |
1099 | cie_compute_hash (cie); | |
1100 | if (hdr_info->cies == NULL) | |
1101 | { | |
1102 | hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free); | |
1103 | if (hdr_info->cies == NULL) | |
1104 | return cie_inf; | |
1105 | } | |
1106 | loc = htab_find_slot_with_hash (hdr_info->cies, cie, cie->hash, INSERT); | |
1107 | if (loc == NULL) | |
1108 | return cie_inf; | |
1109 | ||
1110 | new_cie = (struct cie *) *loc; | |
1111 | if (new_cie == NULL) | |
1112 | { | |
1113 | /* Keep CIE_INF and record it in the hash table. */ | |
a50b1753 | 1114 | new_cie = (struct cie *) malloc (sizeof (struct cie)); |
184d07da RS |
1115 | if (new_cie == NULL) |
1116 | return cie_inf; | |
1117 | ||
1118 | memcpy (new_cie, cie, sizeof (struct cie)); | |
1119 | *loc = new_cie; | |
1120 | } | |
1121 | else | |
1122 | { | |
1123 | /* Merge CIE_INF with NEW_CIE->CIE_INF. */ | |
1124 | cie_inf->removed = 1; | |
1125 | cie_inf->u.cie.merged = 1; | |
1126 | cie_inf->u.cie.u.merged_with = new_cie->cie_inf; | |
1127 | if (cie_inf->u.cie.make_lsda_relative) | |
1128 | new_cie->cie_inf->u.cie.make_lsda_relative = 1; | |
1129 | } | |
1130 | return new_cie->cie_inf; | |
1131 | } | |
1132 | ||
ca92cecb RS |
1133 | /* This function is called for each input file before the .eh_frame |
1134 | section is relocated. It discards duplicate CIEs and FDEs for discarded | |
1135 | functions. The function returns TRUE iff any entries have been | |
1136 | deleted. */ | |
1137 | ||
1138 | bfd_boolean | |
1139 | _bfd_elf_discard_section_eh_frame | |
1140 | (bfd *abfd, struct bfd_link_info *info, asection *sec, | |
1141 | bfd_boolean (*reloc_symbol_deleted_p) (bfd_vma, void *), | |
1142 | struct elf_reloc_cookie *cookie) | |
1143 | { | |
184d07da | 1144 | struct eh_cie_fde *ent; |
ca92cecb RS |
1145 | struct eh_frame_sec_info *sec_info; |
1146 | struct eh_frame_hdr_info *hdr_info; | |
1147 | unsigned int ptr_size, offset; | |
1148 | ||
dbaa2011 | 1149 | if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME) |
4d16d575 AM |
1150 | return FALSE; |
1151 | ||
ca92cecb RS |
1152 | sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info; |
1153 | if (sec_info == NULL) | |
1154 | return FALSE; | |
1155 | ||
e41b3a13 JJ |
1156 | ptr_size = (get_elf_backend_data (sec->owner) |
1157 | ->elf_backend_eh_frame_address_size (sec->owner, sec)); | |
1158 | ||
ca92cecb | 1159 | hdr_info = &elf_hash_table (info)->eh_info; |
fda3ecf2 | 1160 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) |
f60e73e9 AM |
1161 | if (ent->size == 4) |
1162 | /* There should only be one zero terminator, on the last input | |
1163 | file supplying .eh_frame (crtend.o). Remove any others. */ | |
1164 | ent->removed = sec->map_head.s != NULL; | |
1165 | else if (!ent->cie) | |
fda3ecf2 | 1166 | { |
e41b3a13 JJ |
1167 | bfd_boolean keep; |
1168 | if ((sec->flags & SEC_LINKER_CREATED) != 0 && cookie->rels == NULL) | |
1169 | { | |
1170 | unsigned int width | |
1171 | = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); | |
1172 | bfd_vma value | |
1173 | = read_value (abfd, sec->contents + ent->offset + 8 + width, | |
1174 | width, get_DW_EH_PE_signed (ent->fde_encoding)); | |
1175 | keep = value != 0; | |
1176 | } | |
1177 | else | |
1178 | { | |
1179 | cookie->rel = cookie->rels + ent->reloc_index; | |
1180 | /* FIXME: octets_per_byte. */ | |
1181 | BFD_ASSERT (cookie->rel < cookie->relend | |
1182 | && cookie->rel->r_offset == ent->offset + 8); | |
1183 | keep = !(*reloc_symbol_deleted_p) (ent->offset + 8, cookie); | |
1184 | } | |
1185 | if (keep) | |
bce613b9 | 1186 | { |
ca92cecb | 1187 | if (info->shared |
18e04883 | 1188 | && (((ent->fde_encoding & 0x70) == DW_EH_PE_absptr |
6b2cc140 | 1189 | && ent->make_relative == 0) |
18e04883 | 1190 | || (ent->fde_encoding & 0x70) == DW_EH_PE_aligned)) |
ca92cecb RS |
1191 | { |
1192 | /* If a shared library uses absolute pointers | |
1193 | which we cannot turn into PC relative, | |
1194 | don't create the binary search table, | |
1195 | since it is affected by runtime relocations. */ | |
1196 | hdr_info->table = FALSE; | |
1197 | (*info->callbacks->einfo) | |
1198 | (_("%P: fde encoding in %B(%A) prevents .eh_frame_hdr" | |
1199 | " table being created.\n"), abfd, sec); | |
1200 | } | |
1201 | ent->removed = 0; | |
1202 | hdr_info->fde_count++; | |
18e04883 RS |
1203 | ent->u.fde.cie_inf = find_merged_cie (abfd, info, sec, hdr_info, |
1204 | cookie, ent->u.fde.cie_inf); | |
bce613b9 | 1205 | } |
ca92cecb RS |
1206 | } |
1207 | ||
184d07da RS |
1208 | if (sec_info->cies) |
1209 | { | |
1210 | free (sec_info->cies); | |
1211 | sec_info->cies = NULL; | |
1212 | } | |
1213 | ||
ca92cecb RS |
1214 | offset = 0; |
1215 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) | |
1216 | if (!ent->removed) | |
1217 | { | |
353057a5 RS |
1218 | ent->new_offset = offset; |
1219 | offset += size_of_output_cie_fde (ent, ptr_size); | |
fda3ecf2 | 1220 | } |
65765700 | 1221 | |
eea6121a | 1222 | sec->rawsize = sec->size; |
353057a5 | 1223 | sec->size = offset; |
353057a5 | 1224 | return offset != sec->rawsize; |
65765700 JJ |
1225 | } |
1226 | ||
1227 | /* This function is called for .eh_frame_hdr section after | |
1228 | _bfd_elf_discard_section_eh_frame has been called on all .eh_frame | |
1229 | input sections. It finalizes the size of .eh_frame_hdr section. */ | |
1230 | ||
b34976b6 | 1231 | bfd_boolean |
c39a58e6 | 1232 | _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) |
65765700 | 1233 | { |
126495ed | 1234 | struct elf_link_hash_table *htab; |
65765700 | 1235 | struct eh_frame_hdr_info *hdr_info; |
126495ed | 1236 | asection *sec; |
65765700 | 1237 | |
126495ed AM |
1238 | htab = elf_hash_table (info); |
1239 | hdr_info = &htab->eh_info; | |
bce613b9 | 1240 | |
184d07da RS |
1241 | if (hdr_info->cies != NULL) |
1242 | { | |
1243 | htab_delete (hdr_info->cies); | |
1244 | hdr_info->cies = NULL; | |
1245 | } | |
1246 | ||
126495ed AM |
1247 | sec = hdr_info->hdr_sec; |
1248 | if (sec == NULL) | |
b34976b6 | 1249 | return FALSE; |
126495ed | 1250 | |
eea6121a | 1251 | sec->size = EH_FRAME_HDR_SIZE; |
65765700 | 1252 | if (hdr_info->table) |
eea6121a | 1253 | sec->size += 4 + hdr_info->fde_count * 8; |
65765700 | 1254 | |
12bd6957 | 1255 | elf_eh_frame_hdr (abfd) = sec; |
b34976b6 | 1256 | return TRUE; |
65765700 JJ |
1257 | } |
1258 | ||
9a2a56cc AM |
1259 | /* Return true if there is at least one non-empty .eh_frame section in |
1260 | input files. Can only be called after ld has mapped input to | |
1261 | output sections, and before sections are stripped. */ | |
1262 | bfd_boolean | |
1263 | _bfd_elf_eh_frame_present (struct bfd_link_info *info) | |
1264 | { | |
1265 | asection *eh = bfd_get_section_by_name (info->output_bfd, ".eh_frame"); | |
1266 | ||
1267 | if (eh == NULL) | |
1268 | return FALSE; | |
1269 | ||
1270 | /* Count only sections which have at least a single CIE or FDE. | |
1271 | There cannot be any CIE or FDE <= 8 bytes. */ | |
1272 | for (eh = eh->map_head.s; eh != NULL; eh = eh->map_head.s) | |
1273 | if (eh->size > 8) | |
1274 | return TRUE; | |
1275 | ||
1276 | return FALSE; | |
1277 | } | |
1278 | ||
68f69152 JJ |
1279 | /* This function is called from size_dynamic_sections. |
1280 | It needs to decide whether .eh_frame_hdr should be output or not, | |
8423293d AM |
1281 | because when the dynamic symbol table has been sized it is too late |
1282 | to strip sections. */ | |
68f69152 | 1283 | |
b34976b6 | 1284 | bfd_boolean |
c39a58e6 | 1285 | _bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info) |
68f69152 | 1286 | { |
126495ed | 1287 | struct elf_link_hash_table *htab; |
68f69152 JJ |
1288 | struct eh_frame_hdr_info *hdr_info; |
1289 | ||
126495ed AM |
1290 | htab = elf_hash_table (info); |
1291 | hdr_info = &htab->eh_info; | |
1292 | if (hdr_info->hdr_sec == NULL) | |
b34976b6 | 1293 | return TRUE; |
68f69152 | 1294 | |
9a2a56cc AM |
1295 | if (bfd_is_abs_section (hdr_info->hdr_sec->output_section) |
1296 | || !info->eh_frame_hdr | |
1297 | || !_bfd_elf_eh_frame_present (info)) | |
68f69152 | 1298 | { |
8423293d | 1299 | hdr_info->hdr_sec->flags |= SEC_EXCLUDE; |
126495ed | 1300 | hdr_info->hdr_sec = NULL; |
b34976b6 | 1301 | return TRUE; |
68f69152 | 1302 | } |
126495ed | 1303 | |
b34976b6 AM |
1304 | hdr_info->table = TRUE; |
1305 | return TRUE; | |
68f69152 JJ |
1306 | } |
1307 | ||
65765700 JJ |
1308 | /* Adjust an address in the .eh_frame section. Given OFFSET within |
1309 | SEC, this returns the new offset in the adjusted .eh_frame section, | |
1310 | or -1 if the address refers to a CIE/FDE which has been removed | |
1311 | or to offset with dynamic relocation which is no longer needed. */ | |
1312 | ||
1313 | bfd_vma | |
c39a58e6 | 1314 | _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED, |
3d540e93 | 1315 | struct bfd_link_info *info ATTRIBUTE_UNUSED, |
c39a58e6 AM |
1316 | asection *sec, |
1317 | bfd_vma offset) | |
65765700 JJ |
1318 | { |
1319 | struct eh_frame_sec_info *sec_info; | |
1320 | unsigned int lo, hi, mid; | |
1321 | ||
dbaa2011 | 1322 | if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME) |
65765700 | 1323 | return offset; |
a50b1753 | 1324 | sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info; |
65765700 | 1325 | |
eea6121a AM |
1326 | if (offset >= sec->rawsize) |
1327 | return offset - sec->rawsize + sec->size; | |
65765700 JJ |
1328 | |
1329 | lo = 0; | |
1330 | hi = sec_info->count; | |
1331 | mid = 0; | |
1332 | while (lo < hi) | |
1333 | { | |
1334 | mid = (lo + hi) / 2; | |
1335 | if (offset < sec_info->entry[mid].offset) | |
1336 | hi = mid; | |
1337 | else if (offset | |
1338 | >= sec_info->entry[mid].offset + sec_info->entry[mid].size) | |
1339 | lo = mid + 1; | |
1340 | else | |
1341 | break; | |
1342 | } | |
1343 | ||
1344 | BFD_ASSERT (lo < hi); | |
1345 | ||
1346 | /* FDE or CIE was removed. */ | |
1347 | if (sec_info->entry[mid].removed) | |
1348 | return (bfd_vma) -1; | |
1349 | ||
18e04883 RS |
1350 | /* If converting personality pointers to DW_EH_PE_pcrel, there will be |
1351 | no need for run-time relocation against the personality field. */ | |
1352 | if (sec_info->entry[mid].cie | |
1353 | && sec_info->entry[mid].u.cie.make_per_encoding_relative | |
1354 | && offset == (sec_info->entry[mid].offset + 8 | |
1355 | + sec_info->entry[mid].u.cie.personality_offset)) | |
1356 | return (bfd_vma) -2; | |
1357 | ||
65765700 JJ |
1358 | /* If converting to DW_EH_PE_pcrel, there will be no need for run-time |
1359 | relocation against FDE's initial_location field. */ | |
fda3ecf2 | 1360 | if (!sec_info->entry[mid].cie |
6b2cc140 | 1361 | && sec_info->entry[mid].make_relative |
353057a5 RS |
1362 | && offset == sec_info->entry[mid].offset + 8) |
1363 | return (bfd_vma) -2; | |
65765700 | 1364 | |
9e2a4898 JJ |
1365 | /* If converting LSDA pointers to DW_EH_PE_pcrel, there will be no need |
1366 | for run-time relocation against LSDA field. */ | |
fda3ecf2 | 1367 | if (!sec_info->entry[mid].cie |
9f4b847e RS |
1368 | && sec_info->entry[mid].u.fde.cie_inf->u.cie.make_lsda_relative |
1369 | && offset == (sec_info->entry[mid].offset + 8 | |
1370 | + sec_info->entry[mid].lsda_offset)) | |
1371 | return (bfd_vma) -2; | |
9e2a4898 | 1372 | |
ac685e6a JJ |
1373 | /* If converting to DW_EH_PE_pcrel, there will be no need for run-time |
1374 | relocation against DW_CFA_set_loc's arguments. */ | |
1375 | if (sec_info->entry[mid].set_loc | |
6b2cc140 | 1376 | && sec_info->entry[mid].make_relative |
ac685e6a JJ |
1377 | && (offset >= sec_info->entry[mid].offset + 8 |
1378 | + sec_info->entry[mid].set_loc[1])) | |
1379 | { | |
1380 | unsigned int cnt; | |
1381 | ||
1382 | for (cnt = 1; cnt <= sec_info->entry[mid].set_loc[0]; cnt++) | |
1383 | if (offset == sec_info->entry[mid].offset + 8 | |
1384 | + sec_info->entry[mid].set_loc[cnt]) | |
1385 | return (bfd_vma) -2; | |
1386 | } | |
1387 | ||
353057a5 | 1388 | /* Any new augmentation bytes go before the first relocation. */ |
c68836a9 | 1389 | return (offset + sec_info->entry[mid].new_offset |
353057a5 RS |
1390 | - sec_info->entry[mid].offset |
1391 | + extra_augmentation_string_bytes (sec_info->entry + mid) | |
1392 | + extra_augmentation_data_bytes (sec_info->entry + mid)); | |
65765700 JJ |
1393 | } |
1394 | ||
1395 | /* Write out .eh_frame section. This is called with the relocated | |
1396 | contents. */ | |
1397 | ||
b34976b6 | 1398 | bfd_boolean |
c39a58e6 AM |
1399 | _bfd_elf_write_section_eh_frame (bfd *abfd, |
1400 | struct bfd_link_info *info, | |
1401 | asection *sec, | |
1402 | bfd_byte *contents) | |
65765700 JJ |
1403 | { |
1404 | struct eh_frame_sec_info *sec_info; | |
126495ed | 1405 | struct elf_link_hash_table *htab; |
65765700 | 1406 | struct eh_frame_hdr_info *hdr_info; |
65765700 | 1407 | unsigned int ptr_size; |
fda3ecf2 | 1408 | struct eh_cie_fde *ent; |
65765700 | 1409 | |
dbaa2011 | 1410 | if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME) |
5dabe785 | 1411 | /* FIXME: octets_per_byte. */ |
c39a58e6 | 1412 | return bfd_set_section_contents (abfd, sec->output_section, contents, |
eea6121a | 1413 | sec->output_offset, sec->size); |
8c946ed5 RS |
1414 | |
1415 | ptr_size = (get_elf_backend_data (abfd) | |
1416 | ->elf_backend_eh_frame_address_size (abfd, sec)); | |
1417 | BFD_ASSERT (ptr_size != 0); | |
1418 | ||
a50b1753 | 1419 | sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info; |
126495ed AM |
1420 | htab = elf_hash_table (info); |
1421 | hdr_info = &htab->eh_info; | |
3472e2e9 | 1422 | |
126495ed | 1423 | if (hdr_info->table && hdr_info->array == NULL) |
a50b1753 NC |
1424 | hdr_info->array = (struct eh_frame_array_ent *) |
1425 | bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array)); | |
126495ed AM |
1426 | if (hdr_info->array == NULL) |
1427 | hdr_info = NULL; | |
65765700 | 1428 | |
353057a5 RS |
1429 | /* The new offsets can be bigger or smaller than the original offsets. |
1430 | We therefore need to make two passes over the section: one backward | |
1431 | pass to move entries up and one forward pass to move entries down. | |
1432 | The two passes won't interfere with each other because entries are | |
1433 | not reordered */ | |
1434 | for (ent = sec_info->entry + sec_info->count; ent-- != sec_info->entry;) | |
1435 | if (!ent->removed && ent->new_offset > ent->offset) | |
fc802241 | 1436 | memmove (contents + ent->new_offset, contents + ent->offset, ent->size); |
353057a5 RS |
1437 | |
1438 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) | |
1439 | if (!ent->removed && ent->new_offset < ent->offset) | |
fc802241 | 1440 | memmove (contents + ent->new_offset, contents + ent->offset, ent->size); |
353057a5 | 1441 | |
fda3ecf2 | 1442 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) |
65765700 | 1443 | { |
353057a5 RS |
1444 | unsigned char *buf, *end; |
1445 | unsigned int new_size; | |
1446 | ||
fda3ecf2 AM |
1447 | if (ent->removed) |
1448 | continue; | |
1449 | ||
353057a5 RS |
1450 | if (ent->size == 4) |
1451 | { | |
1452 | /* Any terminating FDE must be at the end of the section. */ | |
1453 | BFD_ASSERT (ent == sec_info->entry + sec_info->count - 1); | |
1454 | continue; | |
1455 | } | |
1456 | ||
fc802241 | 1457 | buf = contents + ent->new_offset; |
353057a5 RS |
1458 | end = buf + ent->size; |
1459 | new_size = size_of_output_cie_fde (ent, ptr_size); | |
1460 | ||
a34a056a L |
1461 | /* Update the size. It may be shrinked. */ |
1462 | bfd_put_32 (abfd, new_size - 4, buf); | |
1463 | ||
1464 | /* Filling the extra bytes with DW_CFA_nops. */ | |
353057a5 | 1465 | if (new_size != ent->size) |
a34a056a | 1466 | memset (end, 0, new_size - ent->size); |
353057a5 | 1467 | |
fda3ecf2 | 1468 | if (ent->cie) |
65765700 JJ |
1469 | { |
1470 | /* CIE */ | |
353057a5 | 1471 | if (ent->make_relative |
9f4b847e | 1472 | || ent->u.cie.make_lsda_relative |
6b2cc140 | 1473 | || ent->u.cie.per_encoding_relative) |
65765700 | 1474 | { |
f075ee0c | 1475 | char *aug; |
353057a5 | 1476 | unsigned int action, extra_string, extra_data; |
2c42be65 | 1477 | unsigned int per_width, per_encoding; |
65765700 | 1478 | |
9e2a4898 | 1479 | /* Need to find 'R' or 'L' augmentation's argument and modify |
65765700 | 1480 | DW_EH_PE_* value. */ |
353057a5 | 1481 | action = ((ent->make_relative ? 1 : 0) |
9f4b847e | 1482 | | (ent->u.cie.make_lsda_relative ? 2 : 0) |
6b2cc140 | 1483 | | (ent->u.cie.per_encoding_relative ? 4 : 0)); |
353057a5 RS |
1484 | extra_string = extra_augmentation_string_bytes (ent); |
1485 | extra_data = extra_augmentation_data_bytes (ent); | |
1486 | ||
65765700 JJ |
1487 | /* Skip length, id and version. */ |
1488 | buf += 9; | |
f075ee0c AM |
1489 | aug = (char *) buf; |
1490 | buf += strlen (aug) + 1; | |
2c42be65 RS |
1491 | skip_leb128 (&buf, end); |
1492 | skip_leb128 (&buf, end); | |
1493 | skip_leb128 (&buf, end); | |
65765700 JJ |
1494 | if (*aug == 'z') |
1495 | { | |
353057a5 RS |
1496 | /* The uleb128 will always be a single byte for the kind |
1497 | of augmentation strings that we're prepared to handle. */ | |
1498 | *buf++ += extra_data; | |
65765700 JJ |
1499 | aug++; |
1500 | } | |
1501 | ||
353057a5 RS |
1502 | /* Make room for the new augmentation string and data bytes. */ |
1503 | memmove (buf + extra_string + extra_data, buf, end - buf); | |
f075ee0c | 1504 | memmove (aug + extra_string, aug, buf - (bfd_byte *) aug); |
353057a5 | 1505 | buf += extra_string; |
2c42be65 | 1506 | end += extra_string + extra_data; |
353057a5 RS |
1507 | |
1508 | if (ent->add_augmentation_size) | |
1509 | { | |
1510 | *aug++ = 'z'; | |
1511 | *buf++ = extra_data - 1; | |
1512 | } | |
6b2cc140 | 1513 | if (ent->u.cie.add_fde_encoding) |
353057a5 RS |
1514 | { |
1515 | BFD_ASSERT (action & 1); | |
1516 | *aug++ = 'R'; | |
30af5962 | 1517 | *buf++ = make_pc_relative (DW_EH_PE_absptr, ptr_size); |
353057a5 RS |
1518 | action &= ~1; |
1519 | } | |
1520 | ||
9e2a4898 | 1521 | while (action) |
65765700 JJ |
1522 | switch (*aug++) |
1523 | { | |
1524 | case 'L': | |
9e2a4898 JJ |
1525 | if (action & 2) |
1526 | { | |
fda3ecf2 | 1527 | BFD_ASSERT (*buf == ent->lsda_encoding); |
30af5962 | 1528 | *buf = make_pc_relative (*buf, ptr_size); |
9e2a4898 JJ |
1529 | action &= ~2; |
1530 | } | |
65765700 JJ |
1531 | buf++; |
1532 | break; | |
1533 | case 'P': | |
18e04883 | 1534 | if (ent->u.cie.make_per_encoding_relative) |
a10917ef | 1535 | *buf = make_pc_relative (*buf, ptr_size); |
65765700 | 1536 | per_encoding = *buf++; |
3472e2e9 | 1537 | per_width = get_DW_EH_PE_width (per_encoding, ptr_size); |
65765700 | 1538 | BFD_ASSERT (per_width != 0); |
09ae86c2 | 1539 | BFD_ASSERT (((per_encoding & 0x70) == DW_EH_PE_pcrel) |
6b2cc140 | 1540 | == ent->u.cie.per_encoding_relative); |
18e04883 | 1541 | if ((per_encoding & 0x70) == DW_EH_PE_aligned) |
65765700 JJ |
1542 | buf = (contents |
1543 | + ((buf - contents + per_width - 1) | |
1544 | & ~((bfd_size_type) per_width - 1))); | |
09ae86c2 JJ |
1545 | if (action & 4) |
1546 | { | |
fda3ecf2 AM |
1547 | bfd_vma val; |
1548 | ||
1549 | val = read_value (abfd, buf, per_width, | |
1550 | get_DW_EH_PE_signed (per_encoding)); | |
18e04883 RS |
1551 | if (ent->u.cie.make_per_encoding_relative) |
1552 | val -= (sec->output_section->vma | |
1553 | + sec->output_offset | |
1554 | + (buf - contents)); | |
1555 | else | |
1556 | { | |
1557 | val += (bfd_vma) ent->offset - ent->new_offset; | |
1558 | val -= extra_string + extra_data; | |
1559 | } | |
fda3ecf2 | 1560 | write_value (abfd, buf, val, per_width); |
09ae86c2 JJ |
1561 | action &= ~4; |
1562 | } | |
65765700 JJ |
1563 | buf += per_width; |
1564 | break; | |
9e2a4898 JJ |
1565 | case 'R': |
1566 | if (action & 1) | |
1567 | { | |
fda3ecf2 | 1568 | BFD_ASSERT (*buf == ent->fde_encoding); |
30af5962 | 1569 | *buf = make_pc_relative (*buf, ptr_size); |
9e2a4898 JJ |
1570 | action &= ~1; |
1571 | } | |
1572 | buf++; | |
1573 | break; | |
63752a75 JJ |
1574 | case 'S': |
1575 | break; | |
65765700 JJ |
1576 | default: |
1577 | BFD_FAIL (); | |
1578 | } | |
65765700 JJ |
1579 | } |
1580 | } | |
353057a5 | 1581 | else |
65765700 JJ |
1582 | { |
1583 | /* FDE */ | |
fda3ecf2 | 1584 | bfd_vma value, address; |
9e2a4898 | 1585 | unsigned int width; |
ac685e6a | 1586 | bfd_byte *start; |
155eaaa0 | 1587 | struct eh_cie_fde *cie; |
65765700 | 1588 | |
b34976b6 | 1589 | /* Skip length. */ |
155eaaa0 | 1590 | cie = ent->u.fde.cie_inf; |
65765700 | 1591 | buf += 4; |
fc802241 RS |
1592 | value = ((ent->new_offset + sec->output_offset + 4) |
1593 | - (cie->new_offset + cie->u.cie.u.sec->output_offset)); | |
fda3ecf2 | 1594 | bfd_put_32 (abfd, value, buf); |
65765700 | 1595 | buf += 4; |
fda3ecf2 AM |
1596 | width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); |
1597 | value = read_value (abfd, buf, width, | |
1598 | get_DW_EH_PE_signed (ent->fde_encoding)); | |
1599 | address = value; | |
9e2a4898 | 1600 | if (value) |
65765700 | 1601 | { |
18e04883 | 1602 | switch (ent->fde_encoding & 0x70) |
9e2a4898 | 1603 | { |
9e2a4898 JJ |
1604 | case DW_EH_PE_textrel: |
1605 | BFD_ASSERT (hdr_info == NULL); | |
1606 | break; | |
1607 | case DW_EH_PE_datarel: | |
1608 | { | |
cd9e734e AM |
1609 | switch (abfd->arch_info->arch) |
1610 | { | |
1611 | case bfd_arch_ia64: | |
1612 | BFD_ASSERT (elf_gp (abfd) != 0); | |
1613 | address += elf_gp (abfd); | |
1614 | break; | |
1615 | default: | |
1616 | (*info->callbacks->einfo) | |
1617 | (_("%P: DW_EH_PE_datarel unspecified" | |
1618 | " for this architecture.\n")); | |
1619 | /* Fall thru */ | |
1620 | case bfd_arch_frv: | |
1621 | case bfd_arch_i386: | |
1622 | BFD_ASSERT (htab->hgot != NULL | |
1623 | && ((htab->hgot->root.type | |
1624 | == bfd_link_hash_defined) | |
1625 | || (htab->hgot->root.type | |
1626 | == bfd_link_hash_defweak))); | |
1627 | address | |
1628 | += (htab->hgot->root.u.def.value | |
1629 | + htab->hgot->root.u.def.section->output_offset | |
1630 | + (htab->hgot->root.u.def.section->output_section | |
1631 | ->vma)); | |
1632 | break; | |
1633 | } | |
9e2a4898 JJ |
1634 | } |
1635 | break; | |
1636 | case DW_EH_PE_pcrel: | |
9c47c4c1 | 1637 | value += (bfd_vma) ent->offset - ent->new_offset; |
fc802241 RS |
1638 | address += (sec->output_section->vma |
1639 | + sec->output_offset | |
1640 | + ent->offset + 8); | |
9e2a4898 JJ |
1641 | break; |
1642 | } | |
6b2cc140 | 1643 | if (ent->make_relative) |
fc802241 RS |
1644 | value -= (sec->output_section->vma |
1645 | + sec->output_offset | |
1646 | + ent->new_offset + 8); | |
9e2a4898 | 1647 | write_value (abfd, buf, value, width); |
65765700 JJ |
1648 | } |
1649 | ||
ac685e6a JJ |
1650 | start = buf; |
1651 | ||
65765700 JJ |
1652 | if (hdr_info) |
1653 | { | |
cd9e734e AM |
1654 | /* The address calculation may overflow, giving us a |
1655 | value greater than 4G on a 32-bit target when | |
1656 | dwarf_vma is 64-bit. */ | |
1657 | if (sizeof (address) > 4 && ptr_size == 4) | |
1658 | address &= 0xffffffff; | |
65765700 JJ |
1659 | hdr_info->array[hdr_info->array_count].initial_loc = address; |
1660 | hdr_info->array[hdr_info->array_count++].fde | |
fc802241 RS |
1661 | = (sec->output_section->vma |
1662 | + sec->output_offset | |
1663 | + ent->new_offset); | |
65765700 | 1664 | } |
9e2a4898 | 1665 | |
18e04883 | 1666 | if ((ent->lsda_encoding & 0x70) == DW_EH_PE_pcrel |
9f4b847e | 1667 | || cie->u.cie.make_lsda_relative) |
9e2a4898 | 1668 | { |
fda3ecf2 AM |
1669 | buf += ent->lsda_offset; |
1670 | width = get_DW_EH_PE_width (ent->lsda_encoding, ptr_size); | |
84f97cb6 | 1671 | value = read_value (abfd, buf, width, |
fda3ecf2 | 1672 | get_DW_EH_PE_signed (ent->lsda_encoding)); |
9e2a4898 JJ |
1673 | if (value) |
1674 | { | |
18e04883 | 1675 | if ((ent->lsda_encoding & 0x70) == DW_EH_PE_pcrel) |
9c47c4c1 | 1676 | value += (bfd_vma) ent->offset - ent->new_offset; |
9f4b847e | 1677 | else if (cie->u.cie.make_lsda_relative) |
fc802241 RS |
1678 | value -= (sec->output_section->vma |
1679 | + sec->output_offset | |
1680 | + ent->new_offset + 8 + ent->lsda_offset); | |
9e2a4898 JJ |
1681 | write_value (abfd, buf, value, width); |
1682 | } | |
1683 | } | |
6b2cc140 | 1684 | else if (ent->add_augmentation_size) |
353057a5 RS |
1685 | { |
1686 | /* Skip the PC and length and insert a zero byte for the | |
1687 | augmentation size. */ | |
1688 | buf += width * 2; | |
1689 | memmove (buf + 1, buf, end - buf); | |
1690 | *buf = 0; | |
1691 | } | |
ac685e6a JJ |
1692 | |
1693 | if (ent->set_loc) | |
1694 | { | |
1695 | /* Adjust DW_CFA_set_loc. */ | |
91d6fa6a | 1696 | unsigned int cnt; |
ac685e6a JJ |
1697 | bfd_vma new_offset; |
1698 | ||
1699 | width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); | |
1700 | new_offset = ent->new_offset + 8 | |
1701 | + extra_augmentation_string_bytes (ent) | |
1702 | + extra_augmentation_data_bytes (ent); | |
1703 | ||
1704 | for (cnt = 1; cnt <= ent->set_loc[0]; cnt++) | |
1705 | { | |
ac685e6a JJ |
1706 | buf = start + ent->set_loc[cnt]; |
1707 | ||
1708 | value = read_value (abfd, buf, width, | |
1709 | get_DW_EH_PE_signed (ent->fde_encoding)); | |
1710 | if (!value) | |
1711 | continue; | |
1712 | ||
18e04883 | 1713 | if ((ent->fde_encoding & 0x70) == DW_EH_PE_pcrel) |
9c47c4c1 | 1714 | value += (bfd_vma) ent->offset + 8 - new_offset; |
6b2cc140 | 1715 | if (ent->make_relative) |
fc802241 RS |
1716 | value -= (sec->output_section->vma |
1717 | + sec->output_offset | |
1718 | + new_offset + ent->set_loc[cnt]); | |
ac685e6a JJ |
1719 | write_value (abfd, buf, value, width); |
1720 | } | |
1721 | } | |
65765700 | 1722 | } |
65765700 JJ |
1723 | } |
1724 | ||
a34a056a L |
1725 | /* We don't align the section to its section alignment since the |
1726 | runtime library only expects all CIE/FDE records aligned at | |
4e591bc1 | 1727 | the pointer size. _bfd_elf_discard_section_eh_frame should |
a34a056a L |
1728 | have padded CIE/FDE records to multiple of pointer size with |
1729 | size_of_output_cie_fde. */ | |
1730 | if ((sec->size % ptr_size) != 0) | |
1731 | abort (); | |
a5eb27e6 | 1732 | |
5dabe785 | 1733 | /* FIXME: octets_per_byte. */ |
65765700 | 1734 | return bfd_set_section_contents (abfd, sec->output_section, |
3472e2e9 AM |
1735 | contents, (file_ptr) sec->output_offset, |
1736 | sec->size); | |
65765700 JJ |
1737 | } |
1738 | ||
1739 | /* Helper function used to sort .eh_frame_hdr search table by increasing | |
1740 | VMA of FDE initial location. */ | |
1741 | ||
1742 | static int | |
c39a58e6 | 1743 | vma_compare (const void *a, const void *b) |
65765700 | 1744 | { |
a50b1753 NC |
1745 | const struct eh_frame_array_ent *p = (const struct eh_frame_array_ent *) a; |
1746 | const struct eh_frame_array_ent *q = (const struct eh_frame_array_ent *) b; | |
65765700 JJ |
1747 | if (p->initial_loc > q->initial_loc) |
1748 | return 1; | |
1749 | if (p->initial_loc < q->initial_loc) | |
1750 | return -1; | |
1751 | return 0; | |
1752 | } | |
1753 | ||
1754 | /* Write out .eh_frame_hdr section. This must be called after | |
1755 | _bfd_elf_write_section_eh_frame has been called on all input | |
1756 | .eh_frame sections. | |
1757 | .eh_frame_hdr format: | |
1758 | ubyte version (currently 1) | |
1759 | ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of | |
1760 | .eh_frame section) | |
1761 | ubyte fde_count_enc (DW_EH_PE_* encoding of total FDE count | |
1762 | number (or DW_EH_PE_omit if there is no | |
1763 | binary search table computed)) | |
1764 | ubyte table_enc (DW_EH_PE_* encoding of binary search table, | |
1765 | or DW_EH_PE_omit if not present. | |
1766 | DW_EH_PE_datarel is using address of | |
1767 | .eh_frame_hdr section start as base) | |
1768 | [encoded] eh_frame_ptr (pointer to start of .eh_frame section) | |
1769 | optionally followed by: | |
1770 | [encoded] fde_count (total number of FDEs in .eh_frame section) | |
1771 | fde_count x [encoded] initial_loc, fde | |
1772 | (array of encoded pairs containing | |
1773 | FDE initial_location field and FDE address, | |
5ed6aba4 | 1774 | sorted by increasing initial_loc). */ |
65765700 | 1775 | |
b34976b6 | 1776 | bfd_boolean |
c39a58e6 | 1777 | _bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) |
65765700 | 1778 | { |
126495ed | 1779 | struct elf_link_hash_table *htab; |
65765700 | 1780 | struct eh_frame_hdr_info *hdr_info; |
126495ed | 1781 | asection *sec; |
9f7c3e5e | 1782 | bfd_boolean retval = TRUE; |
65765700 | 1783 | |
126495ed AM |
1784 | htab = elf_hash_table (info); |
1785 | hdr_info = &htab->eh_info; | |
1786 | sec = hdr_info->hdr_sec; | |
65765700 | 1787 | |
9f7c3e5e | 1788 | if (info->eh_frame_hdr && sec != NULL) |
5ed6aba4 | 1789 | { |
9f7c3e5e AM |
1790 | bfd_byte *contents; |
1791 | asection *eh_frame_sec; | |
1792 | bfd_size_type size; | |
1793 | bfd_vma encoded_eh_frame; | |
1794 | ||
1795 | size = EH_FRAME_HDR_SIZE; | |
1796 | if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) | |
1797 | size += 4 + hdr_info->fde_count * 8; | |
1798 | contents = (bfd_byte *) bfd_malloc (size); | |
1799 | if (contents == NULL) | |
1800 | return FALSE; | |
65765700 | 1801 | |
9f7c3e5e AM |
1802 | eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame"); |
1803 | if (eh_frame_sec == NULL) | |
1804 | { | |
1805 | free (contents); | |
1806 | return FALSE; | |
1807 | } | |
ec3391e7 | 1808 | |
9f7c3e5e AM |
1809 | memset (contents, 0, EH_FRAME_HDR_SIZE); |
1810 | /* Version. */ | |
1811 | contents[0] = 1; | |
1812 | /* .eh_frame offset. */ | |
1813 | contents[1] = get_elf_backend_data (abfd)->elf_backend_encode_eh_address | |
1814 | (abfd, info, eh_frame_sec, 0, sec, 4, &encoded_eh_frame); | |
ec3391e7 | 1815 | |
9f7c3e5e AM |
1816 | if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) |
1817 | { | |
1818 | /* FDE count encoding. */ | |
1819 | contents[2] = DW_EH_PE_udata4; | |
1820 | /* Search table encoding. */ | |
1821 | contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; | |
1822 | } | |
1823 | else | |
1824 | { | |
1825 | contents[2] = DW_EH_PE_omit; | |
1826 | contents[3] = DW_EH_PE_omit; | |
1827 | } | |
1828 | bfd_put_32 (abfd, encoded_eh_frame, contents + 4); | |
65765700 | 1829 | |
9f7c3e5e | 1830 | if (contents[2] != DW_EH_PE_omit) |
65765700 | 1831 | { |
9f7c3e5e AM |
1832 | unsigned int i; |
1833 | ||
1834 | bfd_put_32 (abfd, hdr_info->fde_count, contents + EH_FRAME_HDR_SIZE); | |
1835 | qsort (hdr_info->array, hdr_info->fde_count, | |
1836 | sizeof (*hdr_info->array), vma_compare); | |
1837 | for (i = 0; i < hdr_info->fde_count; i++) | |
1838 | { | |
1839 | bfd_put_32 (abfd, | |
1840 | hdr_info->array[i].initial_loc | |
1841 | - sec->output_section->vma, | |
1842 | contents + EH_FRAME_HDR_SIZE + i * 8 + 4); | |
1843 | bfd_put_32 (abfd, | |
1844 | hdr_info->array[i].fde - sec->output_section->vma, | |
1845 | contents + EH_FRAME_HDR_SIZE + i * 8 + 8); | |
1846 | } | |
65765700 | 1847 | } |
65765700 | 1848 | |
9f7c3e5e AM |
1849 | /* FIXME: octets_per_byte. */ |
1850 | retval = bfd_set_section_contents (abfd, sec->output_section, contents, | |
1851 | (file_ptr) sec->output_offset, | |
1852 | sec->size); | |
1853 | free (contents); | |
1854 | } | |
1855 | if (hdr_info->array != NULL) | |
1856 | free (hdr_info->array); | |
5ed6aba4 | 1857 | return retval; |
65765700 | 1858 | } |
ec3391e7 | 1859 | |
8c946ed5 RS |
1860 | /* Return the width of FDE addresses. This is the default implementation. */ |
1861 | ||
1862 | unsigned int | |
1863 | _bfd_elf_eh_frame_address_size (bfd *abfd, asection *sec ATTRIBUTE_UNUSED) | |
1864 | { | |
1865 | return elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 ? 8 : 4; | |
1866 | } | |
1867 | ||
ec3391e7 AO |
1868 | /* Decide whether we can use a PC-relative encoding within the given |
1869 | EH frame section. This is the default implementation. */ | |
1870 | ||
1871 | bfd_boolean | |
1872 | _bfd_elf_can_make_relative (bfd *input_bfd ATTRIBUTE_UNUSED, | |
1873 | struct bfd_link_info *info ATTRIBUTE_UNUSED, | |
1874 | asection *eh_frame_section ATTRIBUTE_UNUSED) | |
1875 | { | |
1876 | return TRUE; | |
1877 | } | |
1878 | ||
1879 | /* Select an encoding for the given address. Preference is given to | |
1880 | PC-relative addressing modes. */ | |
1881 | ||
1882 | bfd_byte | |
1883 | _bfd_elf_encode_eh_address (bfd *abfd ATTRIBUTE_UNUSED, | |
1884 | struct bfd_link_info *info ATTRIBUTE_UNUSED, | |
1885 | asection *osec, bfd_vma offset, | |
1886 | asection *loc_sec, bfd_vma loc_offset, | |
1887 | bfd_vma *encoded) | |
1888 | { | |
1889 | *encoded = osec->vma + offset - | |
1890 | (loc_sec->output_section->vma + loc_sec->output_offset + loc_offset); | |
1891 | return DW_EH_PE_pcrel | DW_EH_PE_sdata4; | |
1892 | } |