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Commit | Line | Data |
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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 | struct eh_cie_fde *cie_inf; |
50 | unsigned char per_encoding; | |
51 | unsigned char lsda_encoding; | |
52 | unsigned char fde_encoding; | |
53 | unsigned char initial_insn_length; | |
9f4b847e | 54 | unsigned char can_make_lsda_relative; |
bce613b9 JJ |
55 | unsigned char initial_instructions[50]; |
56 | }; | |
57 | ||
58 | ||
59 | ||
2c42be65 RS |
60 | /* If *ITER hasn't reached END yet, read the next byte into *RESULT and |
61 | move onto the next byte. Return true on success. */ | |
62 | ||
63 | static inline bfd_boolean | |
64 | read_byte (bfd_byte **iter, bfd_byte *end, unsigned char *result) | |
65 | { | |
66 | if (*iter >= end) | |
67 | return FALSE; | |
68 | *result = *((*iter)++); | |
69 | return TRUE; | |
70 | } | |
71 | ||
72 | /* Move *ITER over LENGTH bytes, or up to END, whichever is closer. | |
73 | Return true it was possible to move LENGTH bytes. */ | |
74 | ||
75 | static inline bfd_boolean | |
76 | skip_bytes (bfd_byte **iter, bfd_byte *end, bfd_size_type length) | |
77 | { | |
78 | if ((bfd_size_type) (end - *iter) < length) | |
79 | { | |
80 | *iter = end; | |
81 | return FALSE; | |
82 | } | |
83 | *iter += length; | |
84 | return TRUE; | |
85 | } | |
86 | ||
87 | /* Move *ITER over an leb128, stopping at END. Return true if the end | |
88 | of the leb128 was found. */ | |
89 | ||
90 | static bfd_boolean | |
91 | skip_leb128 (bfd_byte **iter, bfd_byte *end) | |
92 | { | |
93 | unsigned char byte; | |
94 | do | |
95 | if (!read_byte (iter, end, &byte)) | |
96 | return FALSE; | |
97 | while (byte & 0x80); | |
98 | return TRUE; | |
99 | } | |
100 | ||
101 | /* Like skip_leb128, but treat the leb128 as an unsigned value and | |
102 | store it in *VALUE. */ | |
103 | ||
104 | static bfd_boolean | |
105 | read_uleb128 (bfd_byte **iter, bfd_byte *end, bfd_vma *value) | |
106 | { | |
107 | bfd_byte *start, *p; | |
108 | ||
109 | start = *iter; | |
110 | if (!skip_leb128 (iter, end)) | |
111 | return FALSE; | |
112 | ||
113 | p = *iter; | |
114 | *value = *--p; | |
115 | while (p > start) | |
116 | *value = (*value << 7) | (*--p & 0x7f); | |
117 | ||
118 | return TRUE; | |
119 | } | |
120 | ||
121 | /* Like read_uleb128, but for signed values. */ | |
122 | ||
123 | static bfd_boolean | |
124 | read_sleb128 (bfd_byte **iter, bfd_byte *end, bfd_signed_vma *value) | |
125 | { | |
126 | bfd_byte *start, *p; | |
127 | ||
128 | start = *iter; | |
129 | if (!skip_leb128 (iter, end)) | |
130 | return FALSE; | |
131 | ||
132 | p = *iter; | |
133 | *value = ((*--p & 0x7f) ^ 0x40) - 0x40; | |
134 | while (p > start) | |
135 | *value = (*value << 7) | (*--p & 0x7f); | |
136 | ||
137 | return TRUE; | |
138 | } | |
65765700 JJ |
139 | |
140 | /* Return 0 if either encoding is variable width, or not yet known to bfd. */ | |
141 | ||
142 | static | |
c39a58e6 | 143 | int get_DW_EH_PE_width (int encoding, int ptr_size) |
65765700 JJ |
144 | { |
145 | /* DW_EH_PE_ values of 0x60 and 0x70 weren't defined at the time .eh_frame | |
146 | was added to bfd. */ | |
147 | if ((encoding & 0x60) == 0x60) | |
148 | return 0; | |
149 | ||
150 | switch (encoding & 7) | |
151 | { | |
152 | case DW_EH_PE_udata2: return 2; | |
153 | case DW_EH_PE_udata4: return 4; | |
154 | case DW_EH_PE_udata8: return 8; | |
155 | case DW_EH_PE_absptr: return ptr_size; | |
156 | default: | |
157 | break; | |
158 | } | |
159 | ||
160 | return 0; | |
161 | } | |
162 | ||
84f97cb6 AS |
163 | #define get_DW_EH_PE_signed(encoding) (((encoding) & DW_EH_PE_signed) != 0) |
164 | ||
9e2a4898 JJ |
165 | /* Read a width sized value from memory. */ |
166 | ||
167 | static bfd_vma | |
c39a58e6 | 168 | read_value (bfd *abfd, bfd_byte *buf, int width, int is_signed) |
9e2a4898 JJ |
169 | { |
170 | bfd_vma value; | |
171 | ||
172 | switch (width) | |
173 | { | |
84f97cb6 AS |
174 | case 2: |
175 | if (is_signed) | |
176 | value = bfd_get_signed_16 (abfd, buf); | |
177 | else | |
178 | value = bfd_get_16 (abfd, buf); | |
179 | break; | |
180 | case 4: | |
181 | if (is_signed) | |
182 | value = bfd_get_signed_32 (abfd, buf); | |
183 | else | |
184 | value = bfd_get_32 (abfd, buf); | |
185 | break; | |
186 | case 8: | |
187 | if (is_signed) | |
188 | value = bfd_get_signed_64 (abfd, buf); | |
189 | else | |
190 | value = bfd_get_64 (abfd, buf); | |
191 | break; | |
192 | default: | |
193 | BFD_FAIL (); | |
194 | return 0; | |
9e2a4898 JJ |
195 | } |
196 | ||
197 | return value; | |
198 | } | |
b34976b6 | 199 | |
9e2a4898 JJ |
200 | /* Store a width sized value to memory. */ |
201 | ||
202 | static void | |
c39a58e6 | 203 | write_value (bfd *abfd, bfd_byte *buf, bfd_vma value, int width) |
9e2a4898 JJ |
204 | { |
205 | switch (width) | |
206 | { | |
207 | case 2: bfd_put_16 (abfd, value, buf); break; | |
208 | case 4: bfd_put_32 (abfd, value, buf); break; | |
209 | case 8: bfd_put_64 (abfd, value, buf); break; | |
210 | default: BFD_FAIL (); | |
211 | } | |
212 | } | |
213 | ||
bce613b9 | 214 | /* Return one if C1 and C2 CIEs can be merged. */ |
65765700 | 215 | |
bce613b9 JJ |
216 | static int |
217 | cie_eq (const void *e1, const void *e2) | |
65765700 | 218 | { |
a50b1753 NC |
219 | const struct cie *c1 = (const struct cie *) e1; |
220 | const struct cie *c2 = (const struct cie *) e2; | |
bce613b9 JJ |
221 | |
222 | if (c1->hash == c2->hash | |
223 | && c1->length == c2->length | |
65765700 | 224 | && c1->version == c2->version |
f137a54e | 225 | && c1->local_personality == c2->local_personality |
65765700 JJ |
226 | && strcmp (c1->augmentation, c2->augmentation) == 0 |
227 | && strcmp (c1->augmentation, "eh") != 0 | |
228 | && c1->code_align == c2->code_align | |
229 | && c1->data_align == c2->data_align | |
230 | && c1->ra_column == c2->ra_column | |
231 | && c1->augmentation_size == c2->augmentation_size | |
f137a54e AM |
232 | && memcmp (&c1->personality, &c2->personality, |
233 | sizeof (c1->personality)) == 0 | |
4564fb94 AM |
234 | && (c1->cie_inf->u.cie.u.sec->output_section |
235 | == c2->cie_inf->u.cie.u.sec->output_section) | |
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); | |
4564fb94 | 269 | h = iterative_hash_object (c->cie_inf->u.cie.u.sec->output_section, h); |
bce613b9 JJ |
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 | /* Try to parse .eh_frame section SEC, which belongs to ABFD. Store the |
456 | information in the section's sec_info field on success. COOKIE | |
457 | describes the relocations in SEC. */ | |
458 | ||
459 | void | |
460 | _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, | |
461 | asection *sec, struct elf_reloc_cookie *cookie) | |
65765700 | 462 | { |
acfe5567 RS |
463 | #define REQUIRE(COND) \ |
464 | do \ | |
465 | if (!(COND)) \ | |
466 | goto free_no_table; \ | |
467 | while (0) | |
468 | ||
ca92cecb | 469 | bfd_byte *ehbuf = NULL, *buf, *end; |
bce613b9 | 470 | bfd_byte *last_fde; |
ca92cecb | 471 | struct eh_cie_fde *this_inf; |
bce613b9 | 472 | unsigned int hdr_length, hdr_id; |
184d07da RS |
473 | unsigned int cie_count; |
474 | struct cie *cie, *local_cies = NULL; | |
126495ed | 475 | struct elf_link_hash_table *htab; |
65765700 | 476 | struct eh_frame_hdr_info *hdr_info; |
68f69152 | 477 | struct eh_frame_sec_info *sec_info = NULL; |
65765700 | 478 | unsigned int ptr_size; |
ca92cecb RS |
479 | unsigned int num_cies; |
480 | unsigned int num_entries; | |
9d0a14d3 | 481 | elf_gc_mark_hook_fn gc_mark_hook; |
ca92cecb RS |
482 | |
483 | htab = elf_hash_table (info); | |
484 | hdr_info = &htab->eh_info; | |
65765700 | 485 | |
4d16d575 | 486 | if (sec->size == 0 |
dbaa2011 | 487 | || sec->sec_info_type != SEC_INFO_TYPE_NONE) |
65765700 JJ |
488 | { |
489 | /* This file does not contain .eh_frame information. */ | |
ca92cecb | 490 | return; |
65765700 JJ |
491 | } |
492 | ||
e460dd0d | 493 | if (bfd_is_abs_section (sec->output_section)) |
65765700 JJ |
494 | { |
495 | /* At least one of the sections is being discarded from the | |
3472e2e9 | 496 | link, so we should just ignore them. */ |
ca92cecb | 497 | return; |
65765700 JJ |
498 | } |
499 | ||
500 | /* Read the frame unwind information from abfd. */ | |
501 | ||
acfe5567 | 502 | REQUIRE (bfd_malloc_and_get_section (abfd, sec, &ehbuf)); |
68f69152 | 503 | |
eea6121a | 504 | if (sec->size >= 4 |
65765700 JJ |
505 | && bfd_get_32 (abfd, ehbuf) == 0 |
506 | && cookie->rel == cookie->relend) | |
507 | { | |
508 | /* Empty .eh_frame section. */ | |
509 | free (ehbuf); | |
ca92cecb | 510 | return; |
65765700 JJ |
511 | } |
512 | ||
65765700 JJ |
513 | /* If .eh_frame section size doesn't fit into int, we cannot handle |
514 | it (it would need to use 64-bit .eh_frame format anyway). */ | |
acfe5567 | 515 | REQUIRE (sec->size == (unsigned int) sec->size); |
65765700 | 516 | |
8c946ed5 RS |
517 | ptr_size = (get_elf_backend_data (abfd) |
518 | ->elf_backend_eh_frame_address_size (abfd, sec)); | |
519 | REQUIRE (ptr_size != 0); | |
520 | ||
ca92cecb RS |
521 | /* Go through the section contents and work out how many FDEs and |
522 | CIEs there are. */ | |
65765700 | 523 | buf = ehbuf; |
ca92cecb RS |
524 | end = ehbuf + sec->size; |
525 | num_cies = 0; | |
526 | num_entries = 0; | |
527 | while (buf != end) | |
528 | { | |
529 | num_entries++; | |
530 | ||
531 | /* Read the length of the entry. */ | |
532 | REQUIRE (skip_bytes (&buf, end, 4)); | |
533 | hdr_length = bfd_get_32 (abfd, buf - 4); | |
534 | ||
535 | /* 64-bit .eh_frame is not supported. */ | |
536 | REQUIRE (hdr_length != 0xffffffff); | |
537 | if (hdr_length == 0) | |
538 | break; | |
539 | ||
540 | REQUIRE (skip_bytes (&buf, end, 4)); | |
541 | hdr_id = bfd_get_32 (abfd, buf - 4); | |
542 | if (hdr_id == 0) | |
543 | num_cies++; | |
544 | ||
545 | REQUIRE (skip_bytes (&buf, end, hdr_length - 4)); | |
546 | } | |
547 | ||
a50b1753 NC |
548 | sec_info = (struct eh_frame_sec_info *) |
549 | bfd_zmalloc (sizeof (struct eh_frame_sec_info) | |
550 | + (num_entries - 1) * sizeof (struct eh_cie_fde)); | |
acfe5567 | 551 | REQUIRE (sec_info); |
eea6121a | 552 | |
184d07da | 553 | /* We need to have a "struct cie" for each CIE in this section. */ |
a50b1753 | 554 | local_cies = (struct cie *) bfd_zmalloc (num_cies * sizeof (*local_cies)); |
184d07da | 555 | REQUIRE (local_cies); |
65765700 | 556 | |
5dabe785 | 557 | /* FIXME: octets_per_byte. */ |
65765700 | 558 | #define ENSURE_NO_RELOCS(buf) \ |
acfe5567 RS |
559 | REQUIRE (!(cookie->rel < cookie->relend \ |
560 | && (cookie->rel->r_offset \ | |
561 | < (bfd_size_type) ((buf) - ehbuf)) \ | |
562 | && cookie->rel->r_info != 0)) | |
65765700 | 563 | |
5dabe785 | 564 | /* FIXME: octets_per_byte. */ |
65765700 JJ |
565 | #define SKIP_RELOCS(buf) \ |
566 | while (cookie->rel < cookie->relend \ | |
3472e2e9 | 567 | && (cookie->rel->r_offset \ |
65765700 JJ |
568 | < (bfd_size_type) ((buf) - ehbuf))) \ |
569 | cookie->rel++ | |
570 | ||
5dabe785 | 571 | /* FIXME: octets_per_byte. */ |
65765700 JJ |
572 | #define GET_RELOC(buf) \ |
573 | ((cookie->rel < cookie->relend \ | |
574 | && (cookie->rel->r_offset \ | |
3472e2e9 | 575 | == (bfd_size_type) ((buf) - ehbuf))) \ |
65765700 JJ |
576 | ? cookie->rel : NULL) |
577 | ||
ca92cecb | 578 | buf = ehbuf; |
184d07da | 579 | cie_count = 0; |
9d0a14d3 | 580 | gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook; |
ca92cecb | 581 | while ((bfd_size_type) (buf - ehbuf) != sec->size) |
65765700 | 582 | { |
f075ee0c | 583 | char *aug; |
ca92cecb | 584 | bfd_byte *start, *insns, *insns_end; |
2c42be65 | 585 | bfd_size_type length; |
ac685e6a | 586 | unsigned int set_loc_count; |
65765700 | 587 | |
fda3ecf2 | 588 | this_inf = sec_info->entry + sec_info->count; |
65765700 | 589 | last_fde = buf; |
bce613b9 | 590 | |
bce613b9 JJ |
591 | /* Read the length of the entry. */ |
592 | REQUIRE (skip_bytes (&buf, ehbuf + sec->size, 4)); | |
593 | hdr_length = bfd_get_32 (abfd, buf - 4); | |
acfe5567 | 594 | |
bce613b9 JJ |
595 | /* The CIE/FDE must be fully contained in this input section. */ |
596 | REQUIRE ((bfd_size_type) (buf - ehbuf) + hdr_length <= sec->size); | |
597 | end = buf + hdr_length; | |
65765700 | 598 | |
bce613b9 JJ |
599 | this_inf->offset = last_fde - ehbuf; |
600 | this_inf->size = 4 + hdr_length; | |
155eaaa0 | 601 | this_inf->reloc_index = cookie->rel - cookie->rels; |
bce613b9 JJ |
602 | |
603 | if (hdr_length == 0) | |
604 | { | |
605 | /* A zero-length CIE should only be found at the end of | |
606 | the section. */ | |
607 | REQUIRE ((bfd_size_type) (buf - ehbuf) == sec->size); | |
608 | ENSURE_NO_RELOCS (buf); | |
609 | sec_info->count++; | |
610 | break; | |
65765700 JJ |
611 | } |
612 | ||
bce613b9 JJ |
613 | REQUIRE (skip_bytes (&buf, end, 4)); |
614 | hdr_id = bfd_get_32 (abfd, buf - 4); | |
615 | ||
616 | if (hdr_id == 0) | |
65765700 JJ |
617 | { |
618 | unsigned int initial_insn_length; | |
619 | ||
620 | /* CIE */ | |
bce613b9 JJ |
621 | this_inf->cie = 1; |
622 | ||
184d07da RS |
623 | /* Point CIE to one of the section-local cie structures. */ |
624 | cie = local_cies + cie_count++; | |
625 | ||
ca92cecb | 626 | cie->cie_inf = this_inf; |
bce613b9 | 627 | cie->length = hdr_length; |
ac685e6a | 628 | start = buf; |
bce613b9 | 629 | REQUIRE (read_byte (&buf, end, &cie->version)); |
65765700 JJ |
630 | |
631 | /* Cannot handle unknown versions. */ | |
604282a7 JJ |
632 | REQUIRE (cie->version == 1 |
633 | || cie->version == 3 | |
634 | || cie->version == 4); | |
bce613b9 | 635 | REQUIRE (strlen ((char *) buf) < sizeof (cie->augmentation)); |
65765700 | 636 | |
bce613b9 | 637 | strcpy (cie->augmentation, (char *) buf); |
f075ee0c | 638 | buf = (bfd_byte *) strchr ((char *) buf, '\0') + 1; |
65765700 JJ |
639 | ENSURE_NO_RELOCS (buf); |
640 | if (buf[0] == 'e' && buf[1] == 'h') | |
641 | { | |
642 | /* GCC < 3.0 .eh_frame CIE */ | |
643 | /* We cannot merge "eh" CIEs because __EXCEPTION_TABLE__ | |
644 | is private to each CIE, so we don't need it for anything. | |
645 | Just skip it. */ | |
2c42be65 | 646 | REQUIRE (skip_bytes (&buf, end, ptr_size)); |
65765700 JJ |
647 | SKIP_RELOCS (buf); |
648 | } | |
604282a7 JJ |
649 | if (cie->version >= 4) |
650 | { | |
651 | REQUIRE (buf + 1 < end); | |
652 | REQUIRE (buf[0] == ptr_size); | |
653 | REQUIRE (buf[1] == 0); | |
654 | buf += 2; | |
655 | } | |
bce613b9 JJ |
656 | REQUIRE (read_uleb128 (&buf, end, &cie->code_align)); |
657 | REQUIRE (read_sleb128 (&buf, end, &cie->data_align)); | |
658 | if (cie->version == 1) | |
2c42be65 RS |
659 | { |
660 | REQUIRE (buf < end); | |
bce613b9 | 661 | cie->ra_column = *buf++; |
2c42be65 | 662 | } |
0da76f83 | 663 | else |
bce613b9 | 664 | REQUIRE (read_uleb128 (&buf, end, &cie->ra_column)); |
65765700 | 665 | ENSURE_NO_RELOCS (buf); |
bce613b9 JJ |
666 | cie->lsda_encoding = DW_EH_PE_omit; |
667 | cie->fde_encoding = DW_EH_PE_omit; | |
668 | cie->per_encoding = DW_EH_PE_omit; | |
669 | aug = cie->augmentation; | |
65765700 JJ |
670 | if (aug[0] != 'e' || aug[1] != 'h') |
671 | { | |
672 | if (*aug == 'z') | |
673 | { | |
674 | aug++; | |
bce613b9 | 675 | REQUIRE (read_uleb128 (&buf, end, &cie->augmentation_size)); |
65765700 JJ |
676 | ENSURE_NO_RELOCS (buf); |
677 | } | |
678 | ||
679 | while (*aug != '\0') | |
680 | switch (*aug++) | |
681 | { | |
682 | case 'L': | |
bce613b9 | 683 | REQUIRE (read_byte (&buf, end, &cie->lsda_encoding)); |
65765700 | 684 | ENSURE_NO_RELOCS (buf); |
bce613b9 | 685 | REQUIRE (get_DW_EH_PE_width (cie->lsda_encoding, ptr_size)); |
65765700 JJ |
686 | break; |
687 | case 'R': | |
bce613b9 | 688 | REQUIRE (read_byte (&buf, end, &cie->fde_encoding)); |
65765700 | 689 | ENSURE_NO_RELOCS (buf); |
bce613b9 | 690 | REQUIRE (get_DW_EH_PE_width (cie->fde_encoding, ptr_size)); |
65765700 | 691 | break; |
63752a75 JJ |
692 | case 'S': |
693 | break; | |
65765700 JJ |
694 | case 'P': |
695 | { | |
696 | int per_width; | |
697 | ||
bce613b9 JJ |
698 | REQUIRE (read_byte (&buf, end, &cie->per_encoding)); |
699 | per_width = get_DW_EH_PE_width (cie->per_encoding, | |
65765700 | 700 | ptr_size); |
acfe5567 | 701 | REQUIRE (per_width); |
18e04883 | 702 | if ((cie->per_encoding & 0x70) == DW_EH_PE_aligned) |
2c42be65 RS |
703 | { |
704 | length = -(buf - ehbuf) & (per_width - 1); | |
705 | REQUIRE (skip_bytes (&buf, end, length)); | |
706 | } | |
18e04883 | 707 | this_inf->u.cie.personality_offset = buf - start; |
65765700 | 708 | ENSURE_NO_RELOCS (buf); |
f137a54e | 709 | /* Ensure we have a reloc here. */ |
184d07da RS |
710 | REQUIRE (GET_RELOC (buf)); |
711 | cie->personality.reloc_index | |
712 | = cookie->rel - cookie->rels; | |
713 | /* Cope with MIPS-style composite relocations. */ | |
714 | do | |
715 | cookie->rel++; | |
716 | while (GET_RELOC (buf) != NULL); | |
2c42be65 | 717 | REQUIRE (skip_bytes (&buf, end, per_width)); |
65765700 JJ |
718 | } |
719 | break; | |
720 | default: | |
721 | /* Unrecognized augmentation. Better bail out. */ | |
722 | goto free_no_table; | |
723 | } | |
724 | } | |
725 | ||
726 | /* For shared libraries, try to get rid of as many RELATIVE relocs | |
0bb2d96a | 727 | as possible. */ |
3472e2e9 | 728 | if (info->shared |
ec3391e7 AO |
729 | && (get_elf_backend_data (abfd) |
730 | ->elf_backend_can_make_relative_eh_frame | |
353057a5 RS |
731 | (abfd, info, sec))) |
732 | { | |
18e04883 | 733 | if ((cie->fde_encoding & 0x70) == DW_EH_PE_absptr) |
6b2cc140 | 734 | this_inf->make_relative = 1; |
353057a5 RS |
735 | /* If the CIE doesn't already have an 'R' entry, it's fairly |
736 | easy to add one, provided that there's no aligned data | |
737 | after the augmentation string. */ | |
bce613b9 | 738 | else if (cie->fde_encoding == DW_EH_PE_omit |
18e04883 | 739 | && (cie->per_encoding & 0x70) != DW_EH_PE_aligned) |
353057a5 | 740 | { |
bce613b9 | 741 | if (*cie->augmentation == 0) |
353057a5 | 742 | this_inf->add_augmentation_size = 1; |
6b2cc140 RS |
743 | this_inf->u.cie.add_fde_encoding = 1; |
744 | this_inf->make_relative = 1; | |
353057a5 | 745 | } |
65765700 | 746 | |
18e04883 RS |
747 | if ((cie->lsda_encoding & 0x70) == DW_EH_PE_absptr) |
748 | cie->can_make_lsda_relative = 1; | |
749 | } | |
9e2a4898 | 750 | |
65765700 JJ |
751 | /* If FDE encoding was not specified, it defaults to |
752 | DW_EH_absptr. */ | |
bce613b9 JJ |
753 | if (cie->fde_encoding == DW_EH_PE_omit) |
754 | cie->fde_encoding = DW_EH_PE_absptr; | |
65765700 | 755 | |
dcf507a6 | 756 | initial_insn_length = end - buf; |
99d190fa AM |
757 | cie->initial_insn_length = initial_insn_length; |
758 | memcpy (cie->initial_instructions, buf, | |
759 | initial_insn_length <= sizeof (cie->initial_instructions) | |
760 | ? initial_insn_length : sizeof (cie->initial_instructions)); | |
dcf507a6 | 761 | insns = buf; |
65765700 JJ |
762 | buf += initial_insn_length; |
763 | ENSURE_NO_RELOCS (buf); | |
ca92cecb | 764 | |
da44f4e5 AM |
765 | if (!info->relocatable) |
766 | /* Keep info for merging cies. */ | |
184d07da | 767 | this_inf->u.cie.u.full_cie = cie; |
6b2cc140 | 768 | this_inf->u.cie.per_encoding_relative |
ca92cecb | 769 | = (cie->per_encoding & 0x70) == DW_EH_PE_pcrel; |
65765700 JJ |
770 | } |
771 | else | |
772 | { | |
bce613b9 JJ |
773 | /* Find the corresponding CIE. */ |
774 | unsigned int cie_offset = this_inf->offset + 4 - hdr_id; | |
184d07da RS |
775 | for (cie = local_cies; cie < local_cies + cie_count; cie++) |
776 | if (cie_offset == cie->cie_inf->offset) | |
bce613b9 JJ |
777 | break; |
778 | ||
779 | /* Ensure this FDE references one of the CIEs in this input | |
780 | section. */ | |
184d07da RS |
781 | REQUIRE (cie != local_cies + cie_count); |
782 | this_inf->u.fde.cie_inf = cie->cie_inf; | |
783 | this_inf->make_relative = cie->cie_inf->make_relative; | |
6b2cc140 | 784 | this_inf->add_augmentation_size |
184d07da | 785 | = cie->cie_inf->add_augmentation_size; |
65765700 JJ |
786 | |
787 | ENSURE_NO_RELOCS (buf); | |
e41b3a13 | 788 | if ((sec->flags & SEC_LINKER_CREATED) == 0 || cookie->rels != NULL) |
2a7b2e88 | 789 | { |
e41b3a13 JJ |
790 | asection *rsec; |
791 | ||
792 | REQUIRE (GET_RELOC (buf)); | |
793 | ||
794 | /* Chain together the FDEs for each section. */ | |
795 | rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie); | |
796 | /* RSEC will be NULL if FDE was cleared out as it was belonging to | |
797 | a discarded SHT_GROUP. */ | |
798 | if (rsec) | |
799 | { | |
800 | REQUIRE (rsec->owner == abfd); | |
801 | this_inf->u.fde.next_for_section = elf_fde_list (rsec); | |
802 | elf_fde_list (rsec) = this_inf; | |
803 | } | |
2a7b2e88 | 804 | } |
9d0a14d3 | 805 | |
2c42be65 RS |
806 | /* Skip the initial location and address range. */ |
807 | start = buf; | |
bce613b9 | 808 | length = get_DW_EH_PE_width (cie->fde_encoding, ptr_size); |
2c42be65 RS |
809 | REQUIRE (skip_bytes (&buf, end, 2 * length)); |
810 | ||
811 | /* Skip the augmentation size, if present. */ | |
bce613b9 | 812 | if (cie->augmentation[0] == 'z') |
dcf507a6 RS |
813 | REQUIRE (read_uleb128 (&buf, end, &length)); |
814 | else | |
815 | length = 0; | |
2c42be65 RS |
816 | |
817 | /* Of the supported augmentation characters above, only 'L' | |
818 | adds augmentation data to the FDE. This code would need to | |
819 | be adjusted if any future augmentations do the same thing. */ | |
bce613b9 | 820 | if (cie->lsda_encoding != DW_EH_PE_omit) |
dcf507a6 | 821 | { |
9f4b847e RS |
822 | SKIP_RELOCS (buf); |
823 | if (cie->can_make_lsda_relative && GET_RELOC (buf)) | |
824 | cie->cie_inf->u.cie.make_lsda_relative = 1; | |
dcf507a6 RS |
825 | this_inf->lsda_offset = buf - start; |
826 | /* If there's no 'z' augmentation, we don't know where the | |
827 | CFA insns begin. Assume no padding. */ | |
bce613b9 | 828 | if (cie->augmentation[0] != 'z') |
dcf507a6 RS |
829 | length = end - buf; |
830 | } | |
831 | ||
832 | /* Skip over the augmentation data. */ | |
833 | REQUIRE (skip_bytes (&buf, end, length)); | |
834 | insns = buf; | |
9e2a4898 | 835 | |
bce613b9 | 836 | buf = last_fde + 4 + hdr_length; |
2a7b2e88 | 837 | |
273f4430 JK |
838 | /* For NULL RSEC (cleared FDE belonging to a discarded section) |
839 | the relocations are commonly cleared. We do not sanity check if | |
840 | all these relocations are cleared as (1) relocations to | |
841 | .gcc_except_table will remain uncleared (they will get dropped | |
842 | with the drop of this unused FDE) and (2) BFD already safely drops | |
843 | relocations of any type to .eh_frame by | |
844 | elf_section_ignore_discarded_relocs. | |
845 | TODO: The .gcc_except_table entries should be also filtered as | |
846 | .eh_frame entries; or GCC could rather use COMDAT for them. */ | |
847 | SKIP_RELOCS (buf); | |
65765700 JJ |
848 | } |
849 | ||
dcf507a6 RS |
850 | /* Try to interpret the CFA instructions and find the first |
851 | padding nop. Shrink this_inf's size so that it doesn't | |
ac685e6a | 852 | include the padding. */ |
bce613b9 | 853 | length = get_DW_EH_PE_width (cie->fde_encoding, ptr_size); |
ac685e6a JJ |
854 | set_loc_count = 0; |
855 | insns_end = skip_non_nops (insns, end, length, &set_loc_count); | |
856 | /* If we don't understand the CFA instructions, we can't know | |
857 | what needs to be adjusted there. */ | |
858 | if (insns_end == NULL | |
859 | /* For the time being we don't support DW_CFA_set_loc in | |
860 | CIE instructions. */ | |
861 | || (set_loc_count && this_inf->cie)) | |
862 | goto free_no_table; | |
863 | this_inf->size -= end - insns_end; | |
bce613b9 JJ |
864 | if (insns_end != end && this_inf->cie) |
865 | { | |
866 | cie->initial_insn_length -= end - insns_end; | |
867 | cie->length -= end - insns_end; | |
868 | } | |
ac685e6a | 869 | if (set_loc_count |
18e04883 | 870 | && ((cie->fde_encoding & 0x70) == DW_EH_PE_pcrel |
6b2cc140 | 871 | || this_inf->make_relative)) |
ac685e6a JJ |
872 | { |
873 | unsigned int cnt; | |
874 | bfd_byte *p; | |
875 | ||
a50b1753 NC |
876 | this_inf->set_loc = (unsigned int *) |
877 | bfd_malloc ((set_loc_count + 1) * sizeof (unsigned int)); | |
ac685e6a JJ |
878 | REQUIRE (this_inf->set_loc); |
879 | this_inf->set_loc[0] = set_loc_count; | |
880 | p = insns; | |
881 | cnt = 0; | |
882 | while (p < end) | |
883 | { | |
884 | if (*p == DW_CFA_set_loc) | |
885 | this_inf->set_loc[++cnt] = p + 1 - start; | |
886 | REQUIRE (skip_cfa_op (&p, end, length)); | |
887 | } | |
888 | } | |
dcf507a6 | 889 | |
ca92cecb | 890 | this_inf->removed = 1; |
bce613b9 JJ |
891 | this_inf->fde_encoding = cie->fde_encoding; |
892 | this_inf->lsda_encoding = cie->lsda_encoding; | |
65765700 JJ |
893 | sec_info->count++; |
894 | } | |
ca92cecb | 895 | BFD_ASSERT (sec_info->count == num_entries); |
184d07da | 896 | BFD_ASSERT (cie_count == num_cies); |
65765700 JJ |
897 | |
898 | elf_section_data (sec)->sec_info = sec_info; | |
dbaa2011 | 899 | sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME; |
da44f4e5 | 900 | if (!info->relocatable) |
184d07da | 901 | { |
da44f4e5 | 902 | /* Keep info for merging cies. */ |
184d07da RS |
903 | sec_info->cies = local_cies; |
904 | local_cies = NULL; | |
905 | } | |
ca92cecb | 906 | goto success; |
65765700 | 907 | |
ca92cecb RS |
908 | free_no_table: |
909 | (*info->callbacks->einfo) | |
910 | (_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"), | |
911 | abfd, sec); | |
912 | hdr_info->table = FALSE; | |
913 | if (sec_info) | |
914 | free (sec_info); | |
915 | success: | |
916 | if (ehbuf) | |
917 | free (ehbuf); | |
ca92cecb RS |
918 | if (local_cies) |
919 | free (local_cies); | |
920 | #undef REQUIRE | |
921 | } | |
bce613b9 | 922 | |
9d0a14d3 RS |
923 | /* Mark all relocations against CIE or FDE ENT, which occurs in |
924 | .eh_frame section SEC. COOKIE describes the relocations in SEC; | |
925 | its "rel" field can be changed freely. */ | |
926 | ||
927 | static bfd_boolean | |
928 | mark_entry (struct bfd_link_info *info, asection *sec, | |
929 | struct eh_cie_fde *ent, elf_gc_mark_hook_fn gc_mark_hook, | |
930 | struct elf_reloc_cookie *cookie) | |
931 | { | |
5dabe785 | 932 | /* FIXME: octets_per_byte. */ |
9d0a14d3 RS |
933 | for (cookie->rel = cookie->rels + ent->reloc_index; |
934 | cookie->rel < cookie->relend | |
935 | && cookie->rel->r_offset < ent->offset + ent->size; | |
936 | cookie->rel++) | |
937 | if (!_bfd_elf_gc_mark_reloc (info, sec, gc_mark_hook, cookie)) | |
938 | return FALSE; | |
939 | ||
940 | return TRUE; | |
941 | } | |
942 | ||
943 | /* Mark all the relocations against FDEs that relate to code in input | |
944 | section SEC. The FDEs belong to .eh_frame section EH_FRAME, whose | |
945 | relocations are described by COOKIE. */ | |
946 | ||
947 | bfd_boolean | |
948 | _bfd_elf_gc_mark_fdes (struct bfd_link_info *info, asection *sec, | |
949 | asection *eh_frame, elf_gc_mark_hook_fn gc_mark_hook, | |
950 | struct elf_reloc_cookie *cookie) | |
951 | { | |
184d07da | 952 | struct eh_cie_fde *fde, *cie; |
9d0a14d3 RS |
953 | |
954 | for (fde = elf_fde_list (sec); fde; fde = fde->u.fde.next_for_section) | |
955 | { | |
956 | if (!mark_entry (info, eh_frame, fde, gc_mark_hook, cookie)) | |
957 | return FALSE; | |
958 | ||
959 | /* At this stage, all cie_inf fields point to local CIEs, so we | |
960 | can use the same cookie to refer to them. */ | |
961 | cie = fde->u.fde.cie_inf; | |
184d07da | 962 | if (!cie->u.cie.gc_mark) |
9d0a14d3 | 963 | { |
184d07da | 964 | cie->u.cie.gc_mark = 1; |
9d0a14d3 RS |
965 | if (!mark_entry (info, eh_frame, cie, gc_mark_hook, cookie)) |
966 | return FALSE; | |
967 | } | |
968 | } | |
969 | return TRUE; | |
970 | } | |
971 | ||
184d07da RS |
972 | /* Input section SEC of ABFD is an .eh_frame section that contains the |
973 | CIE described by CIE_INF. Return a version of CIE_INF that is going | |
974 | to be kept in the output, adding CIE_INF to the output if necessary. | |
975 | ||
976 | HDR_INFO is the .eh_frame_hdr information and COOKIE describes the | |
977 | relocations in REL. */ | |
978 | ||
979 | static struct eh_cie_fde * | |
18e04883 | 980 | find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec, |
184d07da RS |
981 | struct eh_frame_hdr_info *hdr_info, |
982 | struct elf_reloc_cookie *cookie, | |
983 | struct eh_cie_fde *cie_inf) | |
984 | { | |
985 | unsigned long r_symndx; | |
986 | struct cie *cie, *new_cie; | |
987 | Elf_Internal_Rela *rel; | |
988 | void **loc; | |
989 | ||
990 | /* Use CIE_INF if we have already decided to keep it. */ | |
991 | if (!cie_inf->removed) | |
992 | return cie_inf; | |
993 | ||
994 | /* If we have merged CIE_INF with another CIE, use that CIE instead. */ | |
995 | if (cie_inf->u.cie.merged) | |
996 | return cie_inf->u.cie.u.merged_with; | |
997 | ||
998 | cie = cie_inf->u.cie.u.full_cie; | |
999 | ||
1000 | /* Assume we will need to keep CIE_INF. */ | |
1001 | cie_inf->removed = 0; | |
1002 | cie_inf->u.cie.u.sec = sec; | |
1003 | ||
1004 | /* If we are not merging CIEs, use CIE_INF. */ | |
1005 | if (cie == NULL) | |
1006 | return cie_inf; | |
1007 | ||
1008 | if (cie->per_encoding != DW_EH_PE_omit) | |
1009 | { | |
18e04883 RS |
1010 | bfd_boolean per_binds_local; |
1011 | ||
5087d529 AM |
1012 | /* Work out the address of personality routine, or at least |
1013 | enough info that we could calculate the address had we made a | |
1014 | final section layout. The symbol on the reloc is enough, | |
1015 | either the hash for a global, or (bfd id, index) pair for a | |
1016 | local. The assumption here is that no one uses addends on | |
1017 | the reloc. */ | |
184d07da RS |
1018 | rel = cookie->rels + cie->personality.reloc_index; |
1019 | memset (&cie->personality, 0, sizeof (cie->personality)); | |
1020 | #ifdef BFD64 | |
1021 | if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64) | |
1022 | r_symndx = ELF64_R_SYM (rel->r_info); | |
1023 | else | |
1024 | #endif | |
1025 | r_symndx = ELF32_R_SYM (rel->r_info); | |
1026 | if (r_symndx >= cookie->locsymcount | |
1027 | || ELF_ST_BIND (cookie->locsyms[r_symndx].st_info) != STB_LOCAL) | |
1028 | { | |
1029 | struct elf_link_hash_entry *h; | |
1030 | ||
1031 | r_symndx -= cookie->extsymoff; | |
1032 | h = cookie->sym_hashes[r_symndx]; | |
1033 | ||
1034 | while (h->root.type == bfd_link_hash_indirect | |
1035 | || h->root.type == bfd_link_hash_warning) | |
1036 | h = (struct elf_link_hash_entry *) h->root.u.i.link; | |
1037 | ||
1038 | cie->personality.h = h; | |
18e04883 | 1039 | per_binds_local = SYMBOL_REFERENCES_LOCAL (info, h); |
184d07da RS |
1040 | } |
1041 | else | |
1042 | { | |
1043 | Elf_Internal_Sym *sym; | |
1044 | asection *sym_sec; | |
1045 | ||
1046 | sym = &cookie->locsyms[r_symndx]; | |
1047 | sym_sec = bfd_section_from_elf_index (abfd, sym->st_shndx); | |
1048 | if (sym_sec == NULL) | |
1049 | return cie_inf; | |
1050 | ||
1051 | if (sym_sec->kept_section != NULL) | |
1052 | sym_sec = sym_sec->kept_section; | |
1053 | if (sym_sec->output_section == NULL) | |
1054 | return cie_inf; | |
1055 | ||
1056 | cie->local_personality = 1; | |
5087d529 AM |
1057 | cie->personality.sym.bfd_id = abfd->id; |
1058 | cie->personality.sym.index = r_symndx; | |
18e04883 RS |
1059 | per_binds_local = TRUE; |
1060 | } | |
1061 | ||
1062 | if (per_binds_local | |
1063 | && info->shared | |
1064 | && (cie->per_encoding & 0x70) == DW_EH_PE_absptr | |
1065 | && (get_elf_backend_data (abfd) | |
1066 | ->elf_backend_can_make_relative_eh_frame (abfd, info, sec))) | |
1067 | { | |
1068 | cie_inf->u.cie.make_per_encoding_relative = 1; | |
1069 | cie_inf->u.cie.per_encoding_relative = 1; | |
184d07da RS |
1070 | } |
1071 | } | |
1072 | ||
1073 | /* See if we can merge this CIE with an earlier one. */ | |
184d07da RS |
1074 | cie_compute_hash (cie); |
1075 | if (hdr_info->cies == NULL) | |
1076 | { | |
1077 | hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free); | |
1078 | if (hdr_info->cies == NULL) | |
1079 | return cie_inf; | |
1080 | } | |
1081 | loc = htab_find_slot_with_hash (hdr_info->cies, cie, cie->hash, INSERT); | |
1082 | if (loc == NULL) | |
1083 | return cie_inf; | |
1084 | ||
1085 | new_cie = (struct cie *) *loc; | |
1086 | if (new_cie == NULL) | |
1087 | { | |
1088 | /* Keep CIE_INF and record it in the hash table. */ | |
a50b1753 | 1089 | new_cie = (struct cie *) malloc (sizeof (struct cie)); |
184d07da RS |
1090 | if (new_cie == NULL) |
1091 | return cie_inf; | |
1092 | ||
1093 | memcpy (new_cie, cie, sizeof (struct cie)); | |
1094 | *loc = new_cie; | |
1095 | } | |
1096 | else | |
1097 | { | |
1098 | /* Merge CIE_INF with NEW_CIE->CIE_INF. */ | |
1099 | cie_inf->removed = 1; | |
1100 | cie_inf->u.cie.merged = 1; | |
1101 | cie_inf->u.cie.u.merged_with = new_cie->cie_inf; | |
1102 | if (cie_inf->u.cie.make_lsda_relative) | |
1103 | new_cie->cie_inf->u.cie.make_lsda_relative = 1; | |
1104 | } | |
1105 | return new_cie->cie_inf; | |
1106 | } | |
1107 | ||
ca92cecb RS |
1108 | /* This function is called for each input file before the .eh_frame |
1109 | section is relocated. It discards duplicate CIEs and FDEs for discarded | |
1110 | functions. The function returns TRUE iff any entries have been | |
1111 | deleted. */ | |
1112 | ||
1113 | bfd_boolean | |
1114 | _bfd_elf_discard_section_eh_frame | |
1115 | (bfd *abfd, struct bfd_link_info *info, asection *sec, | |
1116 | bfd_boolean (*reloc_symbol_deleted_p) (bfd_vma, void *), | |
1117 | struct elf_reloc_cookie *cookie) | |
1118 | { | |
184d07da | 1119 | struct eh_cie_fde *ent; |
ca92cecb RS |
1120 | struct eh_frame_sec_info *sec_info; |
1121 | struct eh_frame_hdr_info *hdr_info; | |
1122 | unsigned int ptr_size, offset; | |
1123 | ||
dbaa2011 | 1124 | if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME) |
4d16d575 AM |
1125 | return FALSE; |
1126 | ||
ca92cecb RS |
1127 | sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info; |
1128 | if (sec_info == NULL) | |
1129 | return FALSE; | |
1130 | ||
e41b3a13 JJ |
1131 | ptr_size = (get_elf_backend_data (sec->owner) |
1132 | ->elf_backend_eh_frame_address_size (sec->owner, sec)); | |
1133 | ||
ca92cecb | 1134 | hdr_info = &elf_hash_table (info)->eh_info; |
fda3ecf2 | 1135 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) |
f60e73e9 AM |
1136 | if (ent->size == 4) |
1137 | /* There should only be one zero terminator, on the last input | |
1138 | file supplying .eh_frame (crtend.o). Remove any others. */ | |
1139 | ent->removed = sec->map_head.s != NULL; | |
1140 | else if (!ent->cie) | |
fda3ecf2 | 1141 | { |
e41b3a13 JJ |
1142 | bfd_boolean keep; |
1143 | if ((sec->flags & SEC_LINKER_CREATED) != 0 && cookie->rels == NULL) | |
1144 | { | |
1145 | unsigned int width | |
1146 | = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); | |
1147 | bfd_vma value | |
1148 | = read_value (abfd, sec->contents + ent->offset + 8 + width, | |
1149 | width, get_DW_EH_PE_signed (ent->fde_encoding)); | |
1150 | keep = value != 0; | |
1151 | } | |
1152 | else | |
1153 | { | |
1154 | cookie->rel = cookie->rels + ent->reloc_index; | |
1155 | /* FIXME: octets_per_byte. */ | |
1156 | BFD_ASSERT (cookie->rel < cookie->relend | |
1157 | && cookie->rel->r_offset == ent->offset + 8); | |
1158 | keep = !(*reloc_symbol_deleted_p) (ent->offset + 8, cookie); | |
1159 | } | |
1160 | if (keep) | |
bce613b9 | 1161 | { |
ca92cecb | 1162 | if (info->shared |
18e04883 | 1163 | && (((ent->fde_encoding & 0x70) == DW_EH_PE_absptr |
6b2cc140 | 1164 | && ent->make_relative == 0) |
18e04883 | 1165 | || (ent->fde_encoding & 0x70) == DW_EH_PE_aligned)) |
ca92cecb RS |
1166 | { |
1167 | /* If a shared library uses absolute pointers | |
1168 | which we cannot turn into PC relative, | |
1169 | don't create the binary search table, | |
1170 | since it is affected by runtime relocations. */ | |
1171 | hdr_info->table = FALSE; | |
1172 | (*info->callbacks->einfo) | |
1173 | (_("%P: fde encoding in %B(%A) prevents .eh_frame_hdr" | |
1174 | " table being created.\n"), abfd, sec); | |
1175 | } | |
1176 | ent->removed = 0; | |
1177 | hdr_info->fde_count++; | |
18e04883 RS |
1178 | ent->u.fde.cie_inf = find_merged_cie (abfd, info, sec, hdr_info, |
1179 | cookie, ent->u.fde.cie_inf); | |
bce613b9 | 1180 | } |
ca92cecb RS |
1181 | } |
1182 | ||
184d07da RS |
1183 | if (sec_info->cies) |
1184 | { | |
1185 | free (sec_info->cies); | |
1186 | sec_info->cies = NULL; | |
1187 | } | |
1188 | ||
ca92cecb RS |
1189 | offset = 0; |
1190 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) | |
1191 | if (!ent->removed) | |
1192 | { | |
353057a5 RS |
1193 | ent->new_offset = offset; |
1194 | offset += size_of_output_cie_fde (ent, ptr_size); | |
fda3ecf2 | 1195 | } |
65765700 | 1196 | |
eea6121a | 1197 | sec->rawsize = sec->size; |
353057a5 | 1198 | sec->size = offset; |
353057a5 | 1199 | return offset != sec->rawsize; |
65765700 JJ |
1200 | } |
1201 | ||
1202 | /* This function is called for .eh_frame_hdr section after | |
1203 | _bfd_elf_discard_section_eh_frame has been called on all .eh_frame | |
1204 | input sections. It finalizes the size of .eh_frame_hdr section. */ | |
1205 | ||
b34976b6 | 1206 | bfd_boolean |
c39a58e6 | 1207 | _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) |
65765700 | 1208 | { |
126495ed | 1209 | struct elf_link_hash_table *htab; |
65765700 | 1210 | struct eh_frame_hdr_info *hdr_info; |
126495ed | 1211 | asection *sec; |
65765700 | 1212 | |
126495ed AM |
1213 | htab = elf_hash_table (info); |
1214 | hdr_info = &htab->eh_info; | |
bce613b9 | 1215 | |
184d07da RS |
1216 | if (hdr_info->cies != NULL) |
1217 | { | |
1218 | htab_delete (hdr_info->cies); | |
1219 | hdr_info->cies = NULL; | |
1220 | } | |
1221 | ||
126495ed AM |
1222 | sec = hdr_info->hdr_sec; |
1223 | if (sec == NULL) | |
b34976b6 | 1224 | return FALSE; |
126495ed | 1225 | |
eea6121a | 1226 | sec->size = EH_FRAME_HDR_SIZE; |
65765700 | 1227 | if (hdr_info->table) |
eea6121a | 1228 | sec->size += 4 + hdr_info->fde_count * 8; |
65765700 | 1229 | |
12bd6957 | 1230 | elf_eh_frame_hdr (abfd) = sec; |
b34976b6 | 1231 | return TRUE; |
65765700 JJ |
1232 | } |
1233 | ||
9a2a56cc AM |
1234 | /* Return true if there is at least one non-empty .eh_frame section in |
1235 | input files. Can only be called after ld has mapped input to | |
1236 | output sections, and before sections are stripped. */ | |
1237 | bfd_boolean | |
1238 | _bfd_elf_eh_frame_present (struct bfd_link_info *info) | |
1239 | { | |
1240 | asection *eh = bfd_get_section_by_name (info->output_bfd, ".eh_frame"); | |
1241 | ||
1242 | if (eh == NULL) | |
1243 | return FALSE; | |
1244 | ||
1245 | /* Count only sections which have at least a single CIE or FDE. | |
1246 | There cannot be any CIE or FDE <= 8 bytes. */ | |
1247 | for (eh = eh->map_head.s; eh != NULL; eh = eh->map_head.s) | |
1248 | if (eh->size > 8) | |
1249 | return TRUE; | |
1250 | ||
1251 | return FALSE; | |
1252 | } | |
1253 | ||
68f69152 JJ |
1254 | /* This function is called from size_dynamic_sections. |
1255 | It needs to decide whether .eh_frame_hdr should be output or not, | |
8423293d AM |
1256 | because when the dynamic symbol table has been sized it is too late |
1257 | to strip sections. */ | |
68f69152 | 1258 | |
b34976b6 | 1259 | bfd_boolean |
c39a58e6 | 1260 | _bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info) |
68f69152 | 1261 | { |
126495ed | 1262 | struct elf_link_hash_table *htab; |
68f69152 JJ |
1263 | struct eh_frame_hdr_info *hdr_info; |
1264 | ||
126495ed AM |
1265 | htab = elf_hash_table (info); |
1266 | hdr_info = &htab->eh_info; | |
1267 | if (hdr_info->hdr_sec == NULL) | |
b34976b6 | 1268 | return TRUE; |
68f69152 | 1269 | |
9a2a56cc AM |
1270 | if (bfd_is_abs_section (hdr_info->hdr_sec->output_section) |
1271 | || !info->eh_frame_hdr | |
1272 | || !_bfd_elf_eh_frame_present (info)) | |
68f69152 | 1273 | { |
8423293d | 1274 | hdr_info->hdr_sec->flags |= SEC_EXCLUDE; |
126495ed | 1275 | hdr_info->hdr_sec = NULL; |
b34976b6 | 1276 | return TRUE; |
68f69152 | 1277 | } |
126495ed | 1278 | |
b34976b6 AM |
1279 | hdr_info->table = TRUE; |
1280 | return TRUE; | |
68f69152 JJ |
1281 | } |
1282 | ||
65765700 JJ |
1283 | /* Adjust an address in the .eh_frame section. Given OFFSET within |
1284 | SEC, this returns the new offset in the adjusted .eh_frame section, | |
1285 | or -1 if the address refers to a CIE/FDE which has been removed | |
1286 | or to offset with dynamic relocation which is no longer needed. */ | |
1287 | ||
1288 | bfd_vma | |
c39a58e6 | 1289 | _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED, |
3d540e93 | 1290 | struct bfd_link_info *info ATTRIBUTE_UNUSED, |
c39a58e6 AM |
1291 | asection *sec, |
1292 | bfd_vma offset) | |
65765700 JJ |
1293 | { |
1294 | struct eh_frame_sec_info *sec_info; | |
1295 | unsigned int lo, hi, mid; | |
1296 | ||
dbaa2011 | 1297 | if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME) |
65765700 | 1298 | return offset; |
a50b1753 | 1299 | sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info; |
65765700 | 1300 | |
eea6121a AM |
1301 | if (offset >= sec->rawsize) |
1302 | return offset - sec->rawsize + sec->size; | |
65765700 JJ |
1303 | |
1304 | lo = 0; | |
1305 | hi = sec_info->count; | |
1306 | mid = 0; | |
1307 | while (lo < hi) | |
1308 | { | |
1309 | mid = (lo + hi) / 2; | |
1310 | if (offset < sec_info->entry[mid].offset) | |
1311 | hi = mid; | |
1312 | else if (offset | |
1313 | >= sec_info->entry[mid].offset + sec_info->entry[mid].size) | |
1314 | lo = mid + 1; | |
1315 | else | |
1316 | break; | |
1317 | } | |
1318 | ||
1319 | BFD_ASSERT (lo < hi); | |
1320 | ||
1321 | /* FDE or CIE was removed. */ | |
1322 | if (sec_info->entry[mid].removed) | |
1323 | return (bfd_vma) -1; | |
1324 | ||
18e04883 RS |
1325 | /* If converting personality pointers to DW_EH_PE_pcrel, there will be |
1326 | no need for run-time relocation against the personality field. */ | |
1327 | if (sec_info->entry[mid].cie | |
1328 | && sec_info->entry[mid].u.cie.make_per_encoding_relative | |
1329 | && offset == (sec_info->entry[mid].offset + 8 | |
1330 | + sec_info->entry[mid].u.cie.personality_offset)) | |
1331 | return (bfd_vma) -2; | |
1332 | ||
65765700 JJ |
1333 | /* If converting to DW_EH_PE_pcrel, there will be no need for run-time |
1334 | relocation against FDE's initial_location field. */ | |
fda3ecf2 | 1335 | if (!sec_info->entry[mid].cie |
6b2cc140 | 1336 | && sec_info->entry[mid].make_relative |
353057a5 RS |
1337 | && offset == sec_info->entry[mid].offset + 8) |
1338 | return (bfd_vma) -2; | |
65765700 | 1339 | |
9e2a4898 JJ |
1340 | /* If converting LSDA pointers to DW_EH_PE_pcrel, there will be no need |
1341 | for run-time relocation against LSDA field. */ | |
fda3ecf2 | 1342 | if (!sec_info->entry[mid].cie |
9f4b847e RS |
1343 | && sec_info->entry[mid].u.fde.cie_inf->u.cie.make_lsda_relative |
1344 | && offset == (sec_info->entry[mid].offset + 8 | |
1345 | + sec_info->entry[mid].lsda_offset)) | |
1346 | return (bfd_vma) -2; | |
9e2a4898 | 1347 | |
ac685e6a JJ |
1348 | /* If converting to DW_EH_PE_pcrel, there will be no need for run-time |
1349 | relocation against DW_CFA_set_loc's arguments. */ | |
1350 | if (sec_info->entry[mid].set_loc | |
6b2cc140 | 1351 | && sec_info->entry[mid].make_relative |
ac685e6a JJ |
1352 | && (offset >= sec_info->entry[mid].offset + 8 |
1353 | + sec_info->entry[mid].set_loc[1])) | |
1354 | { | |
1355 | unsigned int cnt; | |
1356 | ||
1357 | for (cnt = 1; cnt <= sec_info->entry[mid].set_loc[0]; cnt++) | |
1358 | if (offset == sec_info->entry[mid].offset + 8 | |
1359 | + sec_info->entry[mid].set_loc[cnt]) | |
1360 | return (bfd_vma) -2; | |
1361 | } | |
1362 | ||
353057a5 | 1363 | /* Any new augmentation bytes go before the first relocation. */ |
c68836a9 | 1364 | return (offset + sec_info->entry[mid].new_offset |
353057a5 RS |
1365 | - sec_info->entry[mid].offset |
1366 | + extra_augmentation_string_bytes (sec_info->entry + mid) | |
1367 | + extra_augmentation_data_bytes (sec_info->entry + mid)); | |
65765700 JJ |
1368 | } |
1369 | ||
1370 | /* Write out .eh_frame section. This is called with the relocated | |
1371 | contents. */ | |
1372 | ||
b34976b6 | 1373 | bfd_boolean |
c39a58e6 AM |
1374 | _bfd_elf_write_section_eh_frame (bfd *abfd, |
1375 | struct bfd_link_info *info, | |
1376 | asection *sec, | |
1377 | bfd_byte *contents) | |
65765700 JJ |
1378 | { |
1379 | struct eh_frame_sec_info *sec_info; | |
126495ed | 1380 | struct elf_link_hash_table *htab; |
65765700 | 1381 | struct eh_frame_hdr_info *hdr_info; |
65765700 | 1382 | unsigned int ptr_size; |
fda3ecf2 | 1383 | struct eh_cie_fde *ent; |
65765700 | 1384 | |
dbaa2011 | 1385 | if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME) |
5dabe785 | 1386 | /* FIXME: octets_per_byte. */ |
c39a58e6 | 1387 | return bfd_set_section_contents (abfd, sec->output_section, contents, |
eea6121a | 1388 | sec->output_offset, sec->size); |
8c946ed5 RS |
1389 | |
1390 | ptr_size = (get_elf_backend_data (abfd) | |
1391 | ->elf_backend_eh_frame_address_size (abfd, sec)); | |
1392 | BFD_ASSERT (ptr_size != 0); | |
1393 | ||
a50b1753 | 1394 | sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info; |
126495ed AM |
1395 | htab = elf_hash_table (info); |
1396 | hdr_info = &htab->eh_info; | |
3472e2e9 | 1397 | |
126495ed | 1398 | if (hdr_info->table && hdr_info->array == NULL) |
a50b1753 NC |
1399 | hdr_info->array = (struct eh_frame_array_ent *) |
1400 | bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array)); | |
126495ed AM |
1401 | if (hdr_info->array == NULL) |
1402 | hdr_info = NULL; | |
65765700 | 1403 | |
353057a5 RS |
1404 | /* The new offsets can be bigger or smaller than the original offsets. |
1405 | We therefore need to make two passes over the section: one backward | |
1406 | pass to move entries up and one forward pass to move entries down. | |
1407 | The two passes won't interfere with each other because entries are | |
1408 | not reordered */ | |
1409 | for (ent = sec_info->entry + sec_info->count; ent-- != sec_info->entry;) | |
1410 | if (!ent->removed && ent->new_offset > ent->offset) | |
fc802241 | 1411 | memmove (contents + ent->new_offset, contents + ent->offset, ent->size); |
353057a5 RS |
1412 | |
1413 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) | |
1414 | if (!ent->removed && ent->new_offset < ent->offset) | |
fc802241 | 1415 | memmove (contents + ent->new_offset, contents + ent->offset, ent->size); |
353057a5 | 1416 | |
fda3ecf2 | 1417 | for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) |
65765700 | 1418 | { |
353057a5 RS |
1419 | unsigned char *buf, *end; |
1420 | unsigned int new_size; | |
1421 | ||
fda3ecf2 AM |
1422 | if (ent->removed) |
1423 | continue; | |
1424 | ||
353057a5 RS |
1425 | if (ent->size == 4) |
1426 | { | |
1427 | /* Any terminating FDE must be at the end of the section. */ | |
1428 | BFD_ASSERT (ent == sec_info->entry + sec_info->count - 1); | |
1429 | continue; | |
1430 | } | |
1431 | ||
fc802241 | 1432 | buf = contents + ent->new_offset; |
353057a5 RS |
1433 | end = buf + ent->size; |
1434 | new_size = size_of_output_cie_fde (ent, ptr_size); | |
1435 | ||
a34a056a L |
1436 | /* Update the size. It may be shrinked. */ |
1437 | bfd_put_32 (abfd, new_size - 4, buf); | |
1438 | ||
1439 | /* Filling the extra bytes with DW_CFA_nops. */ | |
353057a5 | 1440 | if (new_size != ent->size) |
a34a056a | 1441 | memset (end, 0, new_size - ent->size); |
353057a5 | 1442 | |
fda3ecf2 | 1443 | if (ent->cie) |
65765700 JJ |
1444 | { |
1445 | /* CIE */ | |
353057a5 | 1446 | if (ent->make_relative |
9f4b847e | 1447 | || ent->u.cie.make_lsda_relative |
6b2cc140 | 1448 | || ent->u.cie.per_encoding_relative) |
65765700 | 1449 | { |
f075ee0c | 1450 | char *aug; |
353057a5 | 1451 | unsigned int action, extra_string, extra_data; |
2c42be65 | 1452 | unsigned int per_width, per_encoding; |
65765700 | 1453 | |
9e2a4898 | 1454 | /* Need to find 'R' or 'L' augmentation's argument and modify |
65765700 | 1455 | DW_EH_PE_* value. */ |
353057a5 | 1456 | action = ((ent->make_relative ? 1 : 0) |
9f4b847e | 1457 | | (ent->u.cie.make_lsda_relative ? 2 : 0) |
6b2cc140 | 1458 | | (ent->u.cie.per_encoding_relative ? 4 : 0)); |
353057a5 RS |
1459 | extra_string = extra_augmentation_string_bytes (ent); |
1460 | extra_data = extra_augmentation_data_bytes (ent); | |
1461 | ||
65765700 JJ |
1462 | /* Skip length, id and version. */ |
1463 | buf += 9; | |
f075ee0c AM |
1464 | aug = (char *) buf; |
1465 | buf += strlen (aug) + 1; | |
2c42be65 RS |
1466 | skip_leb128 (&buf, end); |
1467 | skip_leb128 (&buf, end); | |
1468 | skip_leb128 (&buf, end); | |
65765700 JJ |
1469 | if (*aug == 'z') |
1470 | { | |
353057a5 RS |
1471 | /* The uleb128 will always be a single byte for the kind |
1472 | of augmentation strings that we're prepared to handle. */ | |
1473 | *buf++ += extra_data; | |
65765700 JJ |
1474 | aug++; |
1475 | } | |
1476 | ||
353057a5 RS |
1477 | /* Make room for the new augmentation string and data bytes. */ |
1478 | memmove (buf + extra_string + extra_data, buf, end - buf); | |
f075ee0c | 1479 | memmove (aug + extra_string, aug, buf - (bfd_byte *) aug); |
353057a5 | 1480 | buf += extra_string; |
2c42be65 | 1481 | end += extra_string + extra_data; |
353057a5 RS |
1482 | |
1483 | if (ent->add_augmentation_size) | |
1484 | { | |
1485 | *aug++ = 'z'; | |
1486 | *buf++ = extra_data - 1; | |
1487 | } | |
6b2cc140 | 1488 | if (ent->u.cie.add_fde_encoding) |
353057a5 RS |
1489 | { |
1490 | BFD_ASSERT (action & 1); | |
1491 | *aug++ = 'R'; | |
30af5962 | 1492 | *buf++ = make_pc_relative (DW_EH_PE_absptr, ptr_size); |
353057a5 RS |
1493 | action &= ~1; |
1494 | } | |
1495 | ||
9e2a4898 | 1496 | while (action) |
65765700 JJ |
1497 | switch (*aug++) |
1498 | { | |
1499 | case 'L': | |
9e2a4898 JJ |
1500 | if (action & 2) |
1501 | { | |
fda3ecf2 | 1502 | BFD_ASSERT (*buf == ent->lsda_encoding); |
30af5962 | 1503 | *buf = make_pc_relative (*buf, ptr_size); |
9e2a4898 JJ |
1504 | action &= ~2; |
1505 | } | |
65765700 JJ |
1506 | buf++; |
1507 | break; | |
1508 | case 'P': | |
18e04883 | 1509 | if (ent->u.cie.make_per_encoding_relative) |
a10917ef | 1510 | *buf = make_pc_relative (*buf, ptr_size); |
65765700 | 1511 | per_encoding = *buf++; |
3472e2e9 | 1512 | per_width = get_DW_EH_PE_width (per_encoding, ptr_size); |
65765700 | 1513 | BFD_ASSERT (per_width != 0); |
09ae86c2 | 1514 | BFD_ASSERT (((per_encoding & 0x70) == DW_EH_PE_pcrel) |
6b2cc140 | 1515 | == ent->u.cie.per_encoding_relative); |
18e04883 | 1516 | if ((per_encoding & 0x70) == DW_EH_PE_aligned) |
65765700 JJ |
1517 | buf = (contents |
1518 | + ((buf - contents + per_width - 1) | |
1519 | & ~((bfd_size_type) per_width - 1))); | |
09ae86c2 JJ |
1520 | if (action & 4) |
1521 | { | |
fda3ecf2 AM |
1522 | bfd_vma val; |
1523 | ||
1524 | val = read_value (abfd, buf, per_width, | |
1525 | get_DW_EH_PE_signed (per_encoding)); | |
18e04883 RS |
1526 | if (ent->u.cie.make_per_encoding_relative) |
1527 | val -= (sec->output_section->vma | |
1528 | + sec->output_offset | |
1529 | + (buf - contents)); | |
1530 | else | |
1531 | { | |
1532 | val += (bfd_vma) ent->offset - ent->new_offset; | |
1533 | val -= extra_string + extra_data; | |
1534 | } | |
fda3ecf2 | 1535 | write_value (abfd, buf, val, per_width); |
09ae86c2 JJ |
1536 | action &= ~4; |
1537 | } | |
65765700 JJ |
1538 | buf += per_width; |
1539 | break; | |
9e2a4898 JJ |
1540 | case 'R': |
1541 | if (action & 1) | |
1542 | { | |
fda3ecf2 | 1543 | BFD_ASSERT (*buf == ent->fde_encoding); |
30af5962 | 1544 | *buf = make_pc_relative (*buf, ptr_size); |
9e2a4898 JJ |
1545 | action &= ~1; |
1546 | } | |
1547 | buf++; | |
1548 | break; | |
63752a75 JJ |
1549 | case 'S': |
1550 | break; | |
65765700 JJ |
1551 | default: |
1552 | BFD_FAIL (); | |
1553 | } | |
65765700 JJ |
1554 | } |
1555 | } | |
353057a5 | 1556 | else |
65765700 JJ |
1557 | { |
1558 | /* FDE */ | |
fda3ecf2 | 1559 | bfd_vma value, address; |
9e2a4898 | 1560 | unsigned int width; |
ac685e6a | 1561 | bfd_byte *start; |
155eaaa0 | 1562 | struct eh_cie_fde *cie; |
65765700 | 1563 | |
b34976b6 | 1564 | /* Skip length. */ |
155eaaa0 | 1565 | cie = ent->u.fde.cie_inf; |
65765700 | 1566 | buf += 4; |
fc802241 RS |
1567 | value = ((ent->new_offset + sec->output_offset + 4) |
1568 | - (cie->new_offset + cie->u.cie.u.sec->output_offset)); | |
fda3ecf2 | 1569 | bfd_put_32 (abfd, value, buf); |
65765700 | 1570 | buf += 4; |
fda3ecf2 AM |
1571 | width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); |
1572 | value = read_value (abfd, buf, width, | |
1573 | get_DW_EH_PE_signed (ent->fde_encoding)); | |
1574 | address = value; | |
9e2a4898 | 1575 | if (value) |
65765700 | 1576 | { |
18e04883 | 1577 | switch (ent->fde_encoding & 0x70) |
9e2a4898 | 1578 | { |
9e2a4898 JJ |
1579 | case DW_EH_PE_textrel: |
1580 | BFD_ASSERT (hdr_info == NULL); | |
1581 | break; | |
1582 | case DW_EH_PE_datarel: | |
1583 | { | |
cd9e734e AM |
1584 | switch (abfd->arch_info->arch) |
1585 | { | |
1586 | case bfd_arch_ia64: | |
1587 | BFD_ASSERT (elf_gp (abfd) != 0); | |
1588 | address += elf_gp (abfd); | |
1589 | break; | |
1590 | default: | |
1591 | (*info->callbacks->einfo) | |
1592 | (_("%P: DW_EH_PE_datarel unspecified" | |
1593 | " for this architecture.\n")); | |
1594 | /* Fall thru */ | |
1595 | case bfd_arch_frv: | |
1596 | case bfd_arch_i386: | |
1597 | BFD_ASSERT (htab->hgot != NULL | |
1598 | && ((htab->hgot->root.type | |
1599 | == bfd_link_hash_defined) | |
1600 | || (htab->hgot->root.type | |
1601 | == bfd_link_hash_defweak))); | |
1602 | address | |
1603 | += (htab->hgot->root.u.def.value | |
1604 | + htab->hgot->root.u.def.section->output_offset | |
1605 | + (htab->hgot->root.u.def.section->output_section | |
1606 | ->vma)); | |
1607 | break; | |
1608 | } | |
9e2a4898 JJ |
1609 | } |
1610 | break; | |
1611 | case DW_EH_PE_pcrel: | |
9c47c4c1 | 1612 | value += (bfd_vma) ent->offset - ent->new_offset; |
fc802241 RS |
1613 | address += (sec->output_section->vma |
1614 | + sec->output_offset | |
1615 | + ent->offset + 8); | |
9e2a4898 JJ |
1616 | break; |
1617 | } | |
6b2cc140 | 1618 | if (ent->make_relative) |
fc802241 RS |
1619 | value -= (sec->output_section->vma |
1620 | + sec->output_offset | |
1621 | + ent->new_offset + 8); | |
9e2a4898 | 1622 | write_value (abfd, buf, value, width); |
65765700 JJ |
1623 | } |
1624 | ||
ac685e6a JJ |
1625 | start = buf; |
1626 | ||
65765700 JJ |
1627 | if (hdr_info) |
1628 | { | |
cd9e734e AM |
1629 | /* The address calculation may overflow, giving us a |
1630 | value greater than 4G on a 32-bit target when | |
1631 | dwarf_vma is 64-bit. */ | |
1632 | if (sizeof (address) > 4 && ptr_size == 4) | |
1633 | address &= 0xffffffff; | |
65765700 | 1634 | hdr_info->array[hdr_info->array_count].initial_loc = address; |
ae6c7e33 AM |
1635 | hdr_info->array[hdr_info->array_count].range |
1636 | = read_value (abfd, buf + width, width, FALSE); | |
65765700 | 1637 | hdr_info->array[hdr_info->array_count++].fde |
fc802241 RS |
1638 | = (sec->output_section->vma |
1639 | + sec->output_offset | |
1640 | + ent->new_offset); | |
65765700 | 1641 | } |
9e2a4898 | 1642 | |
18e04883 | 1643 | if ((ent->lsda_encoding & 0x70) == DW_EH_PE_pcrel |
9f4b847e | 1644 | || cie->u.cie.make_lsda_relative) |
9e2a4898 | 1645 | { |
fda3ecf2 AM |
1646 | buf += ent->lsda_offset; |
1647 | width = get_DW_EH_PE_width (ent->lsda_encoding, ptr_size); | |
84f97cb6 | 1648 | value = read_value (abfd, buf, width, |
fda3ecf2 | 1649 | get_DW_EH_PE_signed (ent->lsda_encoding)); |
9e2a4898 JJ |
1650 | if (value) |
1651 | { | |
18e04883 | 1652 | if ((ent->lsda_encoding & 0x70) == DW_EH_PE_pcrel) |
9c47c4c1 | 1653 | value += (bfd_vma) ent->offset - ent->new_offset; |
9f4b847e | 1654 | else if (cie->u.cie.make_lsda_relative) |
fc802241 RS |
1655 | value -= (sec->output_section->vma |
1656 | + sec->output_offset | |
1657 | + ent->new_offset + 8 + ent->lsda_offset); | |
9e2a4898 JJ |
1658 | write_value (abfd, buf, value, width); |
1659 | } | |
1660 | } | |
6b2cc140 | 1661 | else if (ent->add_augmentation_size) |
353057a5 RS |
1662 | { |
1663 | /* Skip the PC and length and insert a zero byte for the | |
1664 | augmentation size. */ | |
1665 | buf += width * 2; | |
1666 | memmove (buf + 1, buf, end - buf); | |
1667 | *buf = 0; | |
1668 | } | |
ac685e6a JJ |
1669 | |
1670 | if (ent->set_loc) | |
1671 | { | |
1672 | /* Adjust DW_CFA_set_loc. */ | |
91d6fa6a | 1673 | unsigned int cnt; |
ac685e6a JJ |
1674 | bfd_vma new_offset; |
1675 | ||
1676 | width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); | |
1677 | new_offset = ent->new_offset + 8 | |
1678 | + extra_augmentation_string_bytes (ent) | |
1679 | + extra_augmentation_data_bytes (ent); | |
1680 | ||
1681 | for (cnt = 1; cnt <= ent->set_loc[0]; cnt++) | |
1682 | { | |
ac685e6a JJ |
1683 | buf = start + ent->set_loc[cnt]; |
1684 | ||
1685 | value = read_value (abfd, buf, width, | |
1686 | get_DW_EH_PE_signed (ent->fde_encoding)); | |
1687 | if (!value) | |
1688 | continue; | |
1689 | ||
18e04883 | 1690 | if ((ent->fde_encoding & 0x70) == DW_EH_PE_pcrel) |
9c47c4c1 | 1691 | value += (bfd_vma) ent->offset + 8 - new_offset; |
6b2cc140 | 1692 | if (ent->make_relative) |
fc802241 RS |
1693 | value -= (sec->output_section->vma |
1694 | + sec->output_offset | |
1695 | + new_offset + ent->set_loc[cnt]); | |
ac685e6a JJ |
1696 | write_value (abfd, buf, value, width); |
1697 | } | |
1698 | } | |
65765700 | 1699 | } |
65765700 JJ |
1700 | } |
1701 | ||
a34a056a L |
1702 | /* We don't align the section to its section alignment since the |
1703 | runtime library only expects all CIE/FDE records aligned at | |
4e591bc1 | 1704 | the pointer size. _bfd_elf_discard_section_eh_frame should |
a34a056a L |
1705 | have padded CIE/FDE records to multiple of pointer size with |
1706 | size_of_output_cie_fde. */ | |
1707 | if ((sec->size % ptr_size) != 0) | |
1708 | abort (); | |
a5eb27e6 | 1709 | |
5dabe785 | 1710 | /* FIXME: octets_per_byte. */ |
65765700 | 1711 | return bfd_set_section_contents (abfd, sec->output_section, |
3472e2e9 AM |
1712 | contents, (file_ptr) sec->output_offset, |
1713 | sec->size); | |
65765700 JJ |
1714 | } |
1715 | ||
1716 | /* Helper function used to sort .eh_frame_hdr search table by increasing | |
1717 | VMA of FDE initial location. */ | |
1718 | ||
1719 | static int | |
c39a58e6 | 1720 | vma_compare (const void *a, const void *b) |
65765700 | 1721 | { |
a50b1753 NC |
1722 | const struct eh_frame_array_ent *p = (const struct eh_frame_array_ent *) a; |
1723 | const struct eh_frame_array_ent *q = (const struct eh_frame_array_ent *) b; | |
65765700 JJ |
1724 | if (p->initial_loc > q->initial_loc) |
1725 | return 1; | |
1726 | if (p->initial_loc < q->initial_loc) | |
1727 | return -1; | |
1728 | return 0; | |
1729 | } | |
1730 | ||
1731 | /* Write out .eh_frame_hdr section. This must be called after | |
1732 | _bfd_elf_write_section_eh_frame has been called on all input | |
1733 | .eh_frame sections. | |
1734 | .eh_frame_hdr format: | |
1735 | ubyte version (currently 1) | |
1736 | ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of | |
1737 | .eh_frame section) | |
1738 | ubyte fde_count_enc (DW_EH_PE_* encoding of total FDE count | |
1739 | number (or DW_EH_PE_omit if there is no | |
1740 | binary search table computed)) | |
1741 | ubyte table_enc (DW_EH_PE_* encoding of binary search table, | |
1742 | or DW_EH_PE_omit if not present. | |
1743 | DW_EH_PE_datarel is using address of | |
1744 | .eh_frame_hdr section start as base) | |
1745 | [encoded] eh_frame_ptr (pointer to start of .eh_frame section) | |
1746 | optionally followed by: | |
1747 | [encoded] fde_count (total number of FDEs in .eh_frame section) | |
1748 | fde_count x [encoded] initial_loc, fde | |
1749 | (array of encoded pairs containing | |
1750 | FDE initial_location field and FDE address, | |
5ed6aba4 | 1751 | sorted by increasing initial_loc). */ |
65765700 | 1752 | |
b34976b6 | 1753 | bfd_boolean |
c39a58e6 | 1754 | _bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) |
65765700 | 1755 | { |
126495ed | 1756 | struct elf_link_hash_table *htab; |
65765700 | 1757 | struct eh_frame_hdr_info *hdr_info; |
126495ed | 1758 | asection *sec; |
9f7c3e5e | 1759 | bfd_boolean retval = TRUE; |
65765700 | 1760 | |
126495ed AM |
1761 | htab = elf_hash_table (info); |
1762 | hdr_info = &htab->eh_info; | |
1763 | sec = hdr_info->hdr_sec; | |
65765700 | 1764 | |
9f7c3e5e | 1765 | if (info->eh_frame_hdr && sec != NULL) |
5ed6aba4 | 1766 | { |
9f7c3e5e AM |
1767 | bfd_byte *contents; |
1768 | asection *eh_frame_sec; | |
1769 | bfd_size_type size; | |
1770 | bfd_vma encoded_eh_frame; | |
1771 | ||
1772 | size = EH_FRAME_HDR_SIZE; | |
1773 | if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) | |
1774 | size += 4 + hdr_info->fde_count * 8; | |
1775 | contents = (bfd_byte *) bfd_malloc (size); | |
1776 | if (contents == NULL) | |
1777 | return FALSE; | |
65765700 | 1778 | |
9f7c3e5e AM |
1779 | eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame"); |
1780 | if (eh_frame_sec == NULL) | |
1781 | { | |
1782 | free (contents); | |
1783 | return FALSE; | |
1784 | } | |
ec3391e7 | 1785 | |
9f7c3e5e AM |
1786 | memset (contents, 0, EH_FRAME_HDR_SIZE); |
1787 | /* Version. */ | |
1788 | contents[0] = 1; | |
1789 | /* .eh_frame offset. */ | |
1790 | contents[1] = get_elf_backend_data (abfd)->elf_backend_encode_eh_address | |
1791 | (abfd, info, eh_frame_sec, 0, sec, 4, &encoded_eh_frame); | |
ec3391e7 | 1792 | |
9f7c3e5e AM |
1793 | if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) |
1794 | { | |
1795 | /* FDE count encoding. */ | |
1796 | contents[2] = DW_EH_PE_udata4; | |
1797 | /* Search table encoding. */ | |
1798 | contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; | |
1799 | } | |
1800 | else | |
1801 | { | |
1802 | contents[2] = DW_EH_PE_omit; | |
1803 | contents[3] = DW_EH_PE_omit; | |
1804 | } | |
1805 | bfd_put_32 (abfd, encoded_eh_frame, contents + 4); | |
65765700 | 1806 | |
9f7c3e5e | 1807 | if (contents[2] != DW_EH_PE_omit) |
65765700 | 1808 | { |
9f7c3e5e | 1809 | unsigned int i; |
ae6c7e33 | 1810 | bfd_boolean overlap, overflow; |
9f7c3e5e AM |
1811 | |
1812 | bfd_put_32 (abfd, hdr_info->fde_count, contents + EH_FRAME_HDR_SIZE); | |
1813 | qsort (hdr_info->array, hdr_info->fde_count, | |
1814 | sizeof (*hdr_info->array), vma_compare); | |
ae6c7e33 AM |
1815 | overlap = FALSE; |
1816 | overflow = FALSE; | |
9f7c3e5e AM |
1817 | for (i = 0; i < hdr_info->fde_count; i++) |
1818 | { | |
ae6c7e33 AM |
1819 | bfd_vma val; |
1820 | ||
1821 | val = hdr_info->array[i].initial_loc - sec->output_section->vma; | |
1822 | val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000; | |
1823 | if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 | |
1824 | && (hdr_info->array[i].initial_loc | |
1825 | != sec->output_section->vma + val)) | |
1826 | overflow = TRUE; | |
1827 | bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 4); | |
1828 | val = hdr_info->array[i].fde - sec->output_section->vma; | |
1829 | val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000; | |
1830 | if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 | |
1831 | && (hdr_info->array[i].fde | |
1832 | != sec->output_section->vma + val)) | |
1833 | overflow = TRUE; | |
1834 | bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 8); | |
1835 | if (i != 0 | |
1836 | && (hdr_info->array[i].initial_loc | |
1837 | < (hdr_info->array[i - 1].initial_loc | |
1838 | + hdr_info->array[i - 1].range))) | |
1839 | overlap = TRUE; | |
1840 | } | |
1841 | if (overflow) | |
1842 | (*info->callbacks->einfo) | |
1843 | (_("%P: .eh_frame_hdr entry overflow.\n")); | |
1844 | if (overlap) | |
1845 | (*info->callbacks->einfo) | |
1846 | (_("%P: .eh_frame_hdr refers to overlapping FDEs.\n")); | |
1847 | if (overflow || overlap) | |
1848 | { | |
1849 | bfd_set_error (bfd_error_bad_value); | |
1850 | retval = FALSE; | |
9f7c3e5e | 1851 | } |
65765700 | 1852 | } |
65765700 | 1853 | |
9f7c3e5e | 1854 | /* FIXME: octets_per_byte. */ |
ae6c7e33 AM |
1855 | if (!bfd_set_section_contents (abfd, sec->output_section, contents, |
1856 | (file_ptr) sec->output_offset, | |
1857 | sec->size)) | |
1858 | retval = FALSE; | |
9f7c3e5e AM |
1859 | free (contents); |
1860 | } | |
1861 | if (hdr_info->array != NULL) | |
1862 | free (hdr_info->array); | |
5ed6aba4 | 1863 | return retval; |
65765700 | 1864 | } |
ec3391e7 | 1865 | |
8c946ed5 RS |
1866 | /* Return the width of FDE addresses. This is the default implementation. */ |
1867 | ||
1868 | unsigned int | |
1869 | _bfd_elf_eh_frame_address_size (bfd *abfd, asection *sec ATTRIBUTE_UNUSED) | |
1870 | { | |
1871 | return elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 ? 8 : 4; | |
1872 | } | |
1873 | ||
ec3391e7 AO |
1874 | /* Decide whether we can use a PC-relative encoding within the given |
1875 | EH frame section. This is the default implementation. */ | |
1876 | ||
1877 | bfd_boolean | |
1878 | _bfd_elf_can_make_relative (bfd *input_bfd ATTRIBUTE_UNUSED, | |
1879 | struct bfd_link_info *info ATTRIBUTE_UNUSED, | |
1880 | asection *eh_frame_section ATTRIBUTE_UNUSED) | |
1881 | { | |
1882 | return TRUE; | |
1883 | } | |
1884 | ||
1885 | /* Select an encoding for the given address. Preference is given to | |
1886 | PC-relative addressing modes. */ | |
1887 | ||
1888 | bfd_byte | |
1889 | _bfd_elf_encode_eh_address (bfd *abfd ATTRIBUTE_UNUSED, | |
1890 | struct bfd_link_info *info ATTRIBUTE_UNUSED, | |
1891 | asection *osec, bfd_vma offset, | |
1892 | asection *loc_sec, bfd_vma loc_offset, | |
1893 | bfd_vma *encoded) | |
1894 | { | |
1895 | *encoded = osec->vma + offset - | |
1896 | (loc_sec->output_section->vma + loc_sec->output_offset + loc_offset); | |
1897 | return DW_EH_PE_pcrel | DW_EH_PE_sdata4; | |
1898 | } |