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5c2c6c95 ILT |
1 | // dwarf_reader.h -- parse dwarf2/3 debug information for gold -*- C++ -*- |
2 | ||
43819297 RM |
3 | // Copyright 2007, 2008, 2009, 2010, 2011, 2012, 2013 |
4 | // Free Software Foundation, Inc. | |
5c2c6c95 ILT |
5 | // Written by Ian Lance Taylor <iant@google.com>. |
6 | ||
7 | // This file is part of gold. | |
8 | ||
9 | // This program is free software; you can redistribute it and/or modify | |
10 | // it under the terms of the GNU General Public License as published by | |
11 | // the Free Software Foundation; either version 3 of the License, or | |
12 | // (at your option) any later version. | |
13 | ||
14 | // This program is distributed in the hope that it will be useful, | |
15 | // but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | // GNU General Public License for more details. | |
18 | ||
19 | // You should have received a copy of the GNU General Public License | |
20 | // along with this program; if not, write to the Free Software | |
21 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, | |
22 | // MA 02110-1301, USA. | |
23 | ||
24 | #ifndef GOLD_DWARF_READER_H | |
25 | #define GOLD_DWARF_READER_H | |
26 | ||
27 | #include <vector> | |
4c50553d | 28 | #include <map> |
71ff8986 | 29 | #include <limits.h> |
c1027032 | 30 | #include <sys/types.h> |
5c2c6c95 | 31 | |
4c50553d | 32 | #include "elfcpp.h" |
5c2c6c95 ILT |
33 | #include "elfcpp_swap.h" |
34 | #include "dwarf.h" | |
24badc65 | 35 | #include "reloc.h" |
5c2c6c95 ILT |
36 | |
37 | namespace gold | |
38 | { | |
39 | ||
c1027032 | 40 | class Dwarf_info_reader; |
5c2c6c95 ILT |
41 | struct LineStateMachine; |
42 | ||
c1027032 CC |
43 | // This class is used to extract the section index and offset of |
44 | // the target of a relocation for a given offset within the section. | |
45 | ||
46 | class Elf_reloc_mapper | |
47 | { | |
48 | public: | |
49 | Elf_reloc_mapper() | |
50 | { } | |
51 | ||
52 | virtual | |
53 | ~Elf_reloc_mapper() | |
54 | { } | |
55 | ||
56 | // Initialize the relocation tracker for section RELOC_SHNDX. | |
57 | bool | |
58 | initialize(unsigned int reloc_shndx, unsigned int reloc_type) | |
59 | { return this->do_initialize(reloc_shndx, reloc_type); } | |
60 | ||
61 | // Return the next reloc_offset. | |
62 | off_t | |
63 | next_offset() | |
64 | { return this->do_next_offset(); } | |
65 | ||
66 | // Advance to the next relocation past OFFSET. | |
67 | void | |
68 | advance(off_t offset) | |
69 | { this->do_advance(offset); } | |
70 | ||
71 | // Return the section index and offset within the section of the target | |
72 | // of the relocation for RELOC_OFFSET in the referring section. | |
73 | unsigned int | |
74 | get_reloc_target(off_t reloc_offset, off_t* target_offset) | |
75 | { return this->do_get_reloc_target(reloc_offset, target_offset); } | |
76 | ||
77 | // Checkpoint the current position in the reloc section. | |
78 | uint64_t | |
79 | checkpoint() const | |
80 | { return this->do_checkpoint(); } | |
81 | ||
82 | // Reset the current position to the CHECKPOINT. | |
83 | void | |
84 | reset(uint64_t checkpoint) | |
85 | { this->do_reset(checkpoint); } | |
86 | ||
87 | protected: | |
88 | virtual bool | |
89 | do_initialize(unsigned int, unsigned int) = 0; | |
90 | ||
91 | // Return the next reloc_offset. | |
92 | virtual off_t | |
93 | do_next_offset() = 0; | |
94 | ||
95 | // Advance to the next relocation past OFFSET. | |
96 | virtual void | |
97 | do_advance(off_t offset) = 0; | |
98 | ||
99 | virtual unsigned int | |
100 | do_get_reloc_target(off_t reloc_offset, off_t* target_offset) = 0; | |
101 | ||
102 | // Checkpoint the current position in the reloc section. | |
103 | virtual uint64_t | |
104 | do_checkpoint() const = 0; | |
105 | ||
106 | // Reset the current position to the CHECKPOINT. | |
107 | virtual void | |
108 | do_reset(uint64_t checkpoint) = 0; | |
109 | }; | |
110 | ||
111 | template<int size, bool big_endian> | |
112 | class Sized_elf_reloc_mapper : public Elf_reloc_mapper | |
113 | { | |
114 | public: | |
115 | Sized_elf_reloc_mapper(Object* object, const unsigned char* symtab, | |
116 | off_t symtab_size) | |
117 | : object_(object), symtab_(symtab), symtab_size_(symtab_size), | |
118 | reloc_type_(0), track_relocs_() | |
119 | { } | |
120 | ||
121 | protected: | |
122 | bool | |
123 | do_initialize(unsigned int reloc_shndx, unsigned int reloc_type); | |
124 | ||
125 | // Return the next reloc_offset. | |
126 | virtual off_t | |
127 | do_next_offset() | |
128 | { return this->track_relocs_.next_offset(); } | |
129 | ||
130 | // Advance to the next relocation past OFFSET. | |
131 | virtual void | |
132 | do_advance(off_t offset) | |
133 | { this->track_relocs_.advance(offset); } | |
134 | ||
135 | unsigned int | |
136 | do_get_reloc_target(off_t reloc_offset, off_t* target_offset); | |
137 | ||
138 | // Checkpoint the current position in the reloc section. | |
139 | uint64_t | |
140 | do_checkpoint() const | |
141 | { return this->track_relocs_.checkpoint(); } | |
142 | ||
143 | // Reset the current position to the CHECKPOINT. | |
144 | void | |
145 | do_reset(uint64_t checkpoint) | |
146 | { this->track_relocs_.reset(checkpoint); } | |
147 | ||
148 | private: | |
149 | typedef typename elfcpp::Elf_types<size>::Elf_Addr Address; | |
150 | ||
151 | // Return the section index of symbol SYMNDX, and copy its value to *VALUE. | |
152 | // Set *IS_ORDINARY true if the section index is an ordinary section index. | |
153 | unsigned int | |
154 | symbol_section(unsigned int symndx, Address* value, bool* is_ordinary); | |
155 | ||
156 | // The object file. | |
157 | Object* object_; | |
158 | // The ELF symbol table. | |
159 | const unsigned char* symtab_; | |
160 | // The size of the ELF symbol table. | |
161 | off_t symtab_size_; | |
162 | // Type of the relocation section (SHT_REL or SHT_RELA). | |
163 | unsigned int reloc_type_; | |
164 | // Relocations for the referring section. | |
165 | Track_relocs<size, big_endian> track_relocs_; | |
166 | }; | |
167 | ||
168 | // This class is used to read the abbreviations table from the | |
169 | // .debug_abbrev section of the object file. | |
170 | ||
171 | class Dwarf_abbrev_table | |
172 | { | |
173 | public: | |
174 | // An attribute list entry. | |
175 | struct Attribute | |
176 | { | |
177 | Attribute(unsigned int a, unsigned int f) | |
178 | : attr(a), form(f) | |
179 | { } | |
180 | unsigned int attr; | |
181 | unsigned int form; | |
182 | }; | |
183 | ||
184 | // An abbrev code entry. | |
185 | struct Abbrev_code | |
186 | { | |
187 | Abbrev_code(unsigned int t, bool hc) | |
188 | : tag(t), has_children(hc), has_sibling_attribute(false), attributes() | |
189 | { | |
190 | this->attributes.reserve(10); | |
191 | } | |
192 | ||
193 | void | |
194 | add_attribute(unsigned int attr, unsigned int form) | |
195 | { | |
196 | this->attributes.push_back(Attribute(attr, form)); | |
197 | } | |
198 | ||
199 | // The DWARF tag. | |
200 | unsigned int tag; | |
201 | // True if the DIE has children. | |
202 | bool has_children : 1; | |
203 | // True if the DIE has a sibling attribute. | |
204 | bool has_sibling_attribute : 1; | |
205 | // The list of attributes and forms. | |
206 | std::vector<Attribute> attributes; | |
207 | }; | |
208 | ||
209 | Dwarf_abbrev_table() | |
210 | : abbrev_shndx_(0), abbrev_offset_(0), buffer_(NULL), buffer_end_(NULL), | |
211 | owns_buffer_(false), buffer_pos_(NULL), high_abbrev_codes_() | |
212 | { | |
213 | memset(this->low_abbrev_codes_, 0, sizeof(this->low_abbrev_codes_)); | |
214 | } | |
215 | ||
216 | ~Dwarf_abbrev_table() | |
217 | { | |
218 | if (this->owns_buffer_ && this->buffer_ != NULL) | |
219 | delete[] this->buffer_; | |
220 | this->clear_abbrev_codes(); | |
221 | } | |
222 | ||
223 | // Read the abbrev table from an object file. | |
224 | bool | |
225 | read_abbrevs(Relobj* object, | |
226 | unsigned int abbrev_shndx, | |
227 | off_t abbrev_offset) | |
228 | { | |
229 | // If we've already read this abbrev table, return immediately. | |
230 | if (this->abbrev_shndx_ > 0 | |
231 | && this->abbrev_shndx_ == abbrev_shndx | |
232 | && this->abbrev_offset_ == abbrev_offset) | |
233 | return true; | |
234 | return this->do_read_abbrevs(object, abbrev_shndx, abbrev_offset); | |
235 | } | |
236 | ||
237 | // Return the abbrev code entry for CODE. This is a fast path for | |
238 | // abbrev codes that are in the direct lookup table. If not found | |
239 | // there, we call do_get_abbrev() to do the hard work. | |
240 | const Abbrev_code* | |
241 | get_abbrev(unsigned int code) | |
242 | { | |
243 | if (code < this->low_abbrev_code_max_ | |
244 | && this->low_abbrev_codes_[code] != NULL) | |
245 | return this->low_abbrev_codes_[code]; | |
246 | return this->do_get_abbrev(code); | |
247 | } | |
248 | ||
249 | private: | |
250 | // Read the abbrev table from an object file. | |
251 | bool | |
252 | do_read_abbrevs(Relobj* object, | |
253 | unsigned int abbrev_shndx, | |
254 | off_t abbrev_offset); | |
255 | ||
256 | // Lookup the abbrev code entry for CODE. | |
257 | const Abbrev_code* | |
258 | do_get_abbrev(unsigned int code); | |
259 | ||
260 | // Store an abbrev code entry for CODE. | |
261 | void | |
262 | store_abbrev(unsigned int code, const Abbrev_code* entry) | |
263 | { | |
264 | if (code < this->low_abbrev_code_max_) | |
265 | this->low_abbrev_codes_[code] = entry; | |
266 | else | |
267 | this->high_abbrev_codes_[code] = entry; | |
268 | } | |
269 | ||
270 | // Clear the abbrev code table and release the memory it uses. | |
271 | void | |
272 | clear_abbrev_codes(); | |
273 | ||
274 | typedef Unordered_map<unsigned int, const Abbrev_code*> Abbrev_code_table; | |
275 | ||
276 | // The section index of the current abbrev table. | |
277 | unsigned int abbrev_shndx_; | |
278 | // The offset within the section of the current abbrev table. | |
279 | off_t abbrev_offset_; | |
280 | // The buffer containing the .debug_abbrev section. | |
281 | const unsigned char* buffer_; | |
282 | const unsigned char* buffer_end_; | |
283 | // True if this object owns the buffer and needs to delete it. | |
284 | bool owns_buffer_; | |
285 | // Pointer to the current position in the buffer. | |
286 | const unsigned char* buffer_pos_; | |
287 | // The table of abbrev codes. | |
288 | // We use a direct-lookup array for low abbrev codes, | |
289 | // and store the rest in a hash table. | |
290 | static const unsigned int low_abbrev_code_max_ = 256; | |
291 | const Abbrev_code* low_abbrev_codes_[low_abbrev_code_max_]; | |
292 | Abbrev_code_table high_abbrev_codes_; | |
293 | }; | |
294 | ||
295 | // A DWARF range list. The start and end offsets are relative | |
296 | // to the input section SHNDX. Each range must lie entirely | |
297 | // within a single section. | |
298 | ||
299 | class Dwarf_range_list | |
300 | { | |
301 | public: | |
302 | struct Range | |
303 | { | |
304 | Range(unsigned int a_shndx, off_t a_start, off_t a_end) | |
305 | : shndx(a_shndx), start(a_start), end(a_end) | |
306 | { } | |
307 | ||
308 | unsigned int shndx; | |
309 | off_t start; | |
310 | off_t end; | |
311 | }; | |
312 | ||
313 | Dwarf_range_list() | |
314 | : range_list_() | |
315 | { } | |
316 | ||
317 | void | |
318 | add(unsigned int shndx, off_t start, off_t end) | |
319 | { this->range_list_.push_back(Range(shndx, start, end)); } | |
320 | ||
321 | size_t | |
322 | size() const | |
323 | { return this->range_list_.size(); } | |
324 | ||
325 | const Range& | |
326 | operator[](off_t i) const | |
327 | { return this->range_list_[i]; } | |
328 | ||
329 | private: | |
330 | std::vector<Range> range_list_; | |
331 | }; | |
332 | ||
333 | // This class is used to read the ranges table from the | |
334 | // .debug_ranges section of the object file. | |
335 | ||
336 | class Dwarf_ranges_table | |
337 | { | |
338 | public: | |
ed5d6712 CC |
339 | Dwarf_ranges_table(Dwarf_info_reader* dwinfo) |
340 | : dwinfo_(dwinfo), ranges_shndx_(0), ranges_buffer_(NULL), | |
341 | ranges_buffer_end_(NULL), owns_ranges_buffer_(false), | |
267257d2 | 342 | ranges_reloc_mapper_(NULL), reloc_type_(0), output_section_offset_(0) |
c1027032 CC |
343 | { } |
344 | ||
345 | ~Dwarf_ranges_table() | |
346 | { | |
347 | if (this->owns_ranges_buffer_ && this->ranges_buffer_ != NULL) | |
348 | delete[] this->ranges_buffer_; | |
349 | if (this->ranges_reloc_mapper_ != NULL) | |
350 | delete this->ranges_reloc_mapper_; | |
351 | } | |
352 | ||
353 | // Read the ranges table from an object file. | |
354 | bool | |
355 | read_ranges_table(Relobj* object, | |
356 | const unsigned char* symtab, | |
357 | off_t symtab_size, | |
358 | unsigned int ranges_shndx); | |
359 | ||
360 | // Read the range table from an object file. | |
361 | Dwarf_range_list* | |
362 | read_range_list(Relobj* object, | |
363 | const unsigned char* symtab, | |
364 | off_t symtab_size, | |
365 | unsigned int address_size, | |
366 | unsigned int ranges_shndx, | |
367 | off_t ranges_offset); | |
368 | ||
267257d2 CC |
369 | // Look for a relocation at offset OFF in the range table, |
370 | // and return the section index and offset of the target. | |
371 | unsigned int | |
372 | lookup_reloc(off_t off, off_t* target_off); | |
373 | ||
c1027032 | 374 | private: |
ed5d6712 CC |
375 | // The Dwarf_info_reader, for reading data. |
376 | Dwarf_info_reader* dwinfo_; | |
c1027032 CC |
377 | // The section index of the ranges table. |
378 | unsigned int ranges_shndx_; | |
379 | // The buffer containing the .debug_ranges section. | |
380 | const unsigned char* ranges_buffer_; | |
381 | const unsigned char* ranges_buffer_end_; | |
382 | // True if this object owns the buffer and needs to delete it. | |
383 | bool owns_ranges_buffer_; | |
384 | // Relocation mapper for the .debug_ranges section. | |
385 | Elf_reloc_mapper* ranges_reloc_mapper_; | |
267257d2 CC |
386 | // Type of the relocation section (SHT_REL or SHT_RELA). |
387 | unsigned int reloc_type_; | |
c1027032 CC |
388 | // For incremental update links, this will hold the offset of the |
389 | // input section within the output section. Offsets read from | |
390 | // relocated data will be relative to the output section, and need | |
391 | // to be corrected before reading data from the input section. | |
392 | uint64_t output_section_offset_; | |
393 | }; | |
394 | ||
395 | // This class is used to read the pubnames and pubtypes tables from the | |
396 | // .debug_pubnames and .debug_pubtypes sections of the object file. | |
397 | ||
398 | class Dwarf_pubnames_table | |
399 | { | |
400 | public: | |
ed5d6712 CC |
401 | Dwarf_pubnames_table(Dwarf_info_reader* dwinfo, bool is_pubtypes) |
402 | : dwinfo_(dwinfo), buffer_(NULL), buffer_end_(NULL), owns_buffer_(false), | |
ec673e64 CC |
403 | offset_size_(0), pinfo_(NULL), end_of_table_(NULL), |
404 | is_pubtypes_(is_pubtypes), is_gnu_style_(false), | |
234d4ab8 | 405 | output_section_offset_(0), unit_length_(0), cu_offset_(0) |
c1027032 CC |
406 | { } |
407 | ||
408 | ~Dwarf_pubnames_table() | |
409 | { | |
410 | if (this->owns_buffer_ && this->buffer_ != NULL) | |
411 | delete[] this->buffer_; | |
412 | } | |
413 | ||
234d4ab8 SA |
414 | // Read the pubnames section from the object file, using the symbol |
415 | // table for relocating it. | |
c1027032 | 416 | bool |
234d4ab8 SA |
417 | read_section(Relobj* object, const unsigned char* symbol_table, |
418 | off_t symtab_size); | |
c1027032 CC |
419 | |
420 | // Read the header for the set at OFFSET. | |
421 | bool | |
422 | read_header(off_t offset); | |
423 | ||
234d4ab8 SA |
424 | // Return the offset to the cu within the info or types section. |
425 | off_t | |
426 | cu_offset() | |
427 | { return this->cu_offset_; } | |
428 | ||
429 | // Return the size of this subsection of the table. The unit length | |
430 | // doesn't include the size of its own field. | |
431 | off_t | |
432 | subsection_size() | |
433 | { return this->unit_length_; } | |
434 | ||
ec673e64 CC |
435 | // Read the next name from the set. If the pubname table is gnu-style, |
436 | // FLAG_BYTE is set to the high-byte of a gdb_index version 7 cu_index. | |
c1027032 | 437 | const char* |
ec673e64 | 438 | next_name(uint8_t* flag_byte); |
c1027032 CC |
439 | |
440 | private: | |
ed5d6712 CC |
441 | // The Dwarf_info_reader, for reading data. |
442 | Dwarf_info_reader* dwinfo_; | |
c1027032 CC |
443 | // The buffer containing the .debug_ranges section. |
444 | const unsigned char* buffer_; | |
445 | const unsigned char* buffer_end_; | |
446 | // True if this object owns the buffer and needs to delete it. | |
447 | bool owns_buffer_; | |
448 | // The size of a DWARF offset for the current set. | |
449 | unsigned int offset_size_; | |
450 | // The current position within the buffer. | |
451 | const unsigned char* pinfo_; | |
ec673e64 CC |
452 | // The end of the current pubnames table. |
453 | const unsigned char* end_of_table_; | |
c1027032 CC |
454 | // TRUE if this is a .debug_pubtypes section. |
455 | bool is_pubtypes_; | |
ec673e64 CC |
456 | // Gnu-style pubnames table. This style has an extra flag byte between the |
457 | // offset and the name, and is used for generating version 7 of gdb-index. | |
458 | bool is_gnu_style_; | |
c1027032 CC |
459 | // For incremental update links, this will hold the offset of the |
460 | // input section within the output section. Offsets read from | |
461 | // relocated data will be relative to the output section, and need | |
462 | // to be corrected before reading data from the input section. | |
463 | uint64_t output_section_offset_; | |
234d4ab8 SA |
464 | // Fields read from the header. |
465 | uint64_t unit_length_; | |
466 | off_t cu_offset_; | |
467 | ||
468 | // Track relocations for this table so we can find the CUs that | |
469 | // correspond to the subsections. | |
470 | Elf_reloc_mapper* reloc_mapper_; | |
471 | // Type of the relocation section (SHT_REL or SHT_RELA). | |
472 | unsigned int reloc_type_; | |
c1027032 CC |
473 | }; |
474 | ||
475 | // This class represents a DWARF Debug Info Entry (DIE). | |
476 | ||
477 | class Dwarf_die | |
478 | { | |
479 | public: | |
480 | // An attribute value. | |
481 | struct Attribute_value | |
482 | { | |
483 | unsigned int attr; | |
484 | unsigned int form; | |
485 | union | |
486 | { | |
487 | int64_t intval; | |
488 | uint64_t uintval; | |
489 | const char* stringval; | |
490 | const unsigned char* blockval; | |
491 | off_t refval; | |
492 | } val; | |
493 | union | |
494 | { | |
495 | // Section index for reference forms. | |
496 | unsigned int shndx; | |
497 | // Block length for block forms. | |
498 | unsigned int blocklen; | |
499 | // Attribute offset for DW_FORM_strp. | |
500 | unsigned int attr_off; | |
501 | } aux; | |
502 | }; | |
503 | ||
504 | // A list of attribute values. | |
505 | typedef std::vector<Attribute_value> Attributes; | |
506 | ||
507 | Dwarf_die(Dwarf_info_reader* dwinfo, | |
508 | off_t die_offset, | |
509 | Dwarf_die* parent); | |
510 | ||
511 | // Return the DWARF tag for this DIE. | |
512 | unsigned int | |
513 | tag() const | |
514 | { | |
515 | if (this->abbrev_code_ == NULL) | |
516 | return 0; | |
517 | return this->abbrev_code_->tag; | |
518 | } | |
519 | ||
520 | // Return true if this DIE has children. | |
521 | bool | |
522 | has_children() const | |
523 | { | |
524 | gold_assert(this->abbrev_code_ != NULL); | |
525 | return this->abbrev_code_->has_children; | |
526 | } | |
527 | ||
528 | // Return true if this DIE has a sibling attribute. | |
529 | bool | |
530 | has_sibling_attribute() const | |
531 | { | |
532 | gold_assert(this->abbrev_code_ != NULL); | |
533 | return this->abbrev_code_->has_sibling_attribute; | |
534 | } | |
535 | ||
536 | // Return the value of attribute ATTR. | |
537 | const Attribute_value* | |
538 | attribute(unsigned int attr); | |
539 | ||
540 | // Return the value of the DW_AT_name attribute. | |
541 | const char* | |
542 | name() | |
543 | { | |
544 | if (this->name_ == NULL) | |
545 | this->set_name(); | |
546 | return this->name_; | |
547 | } | |
548 | ||
549 | // Return the value of the DW_AT_linkage_name | |
550 | // or DW_AT_MIPS_linkage_name attribute. | |
551 | const char* | |
552 | linkage_name() | |
553 | { | |
554 | if (this->linkage_name_ == NULL) | |
555 | this->set_linkage_name(); | |
556 | return this->linkage_name_; | |
557 | } | |
558 | ||
559 | // Return the value of the DW_AT_specification attribute. | |
560 | off_t | |
561 | specification() | |
562 | { | |
563 | if (!this->attributes_read_) | |
564 | this->read_attributes(); | |
565 | return this->specification_; | |
566 | } | |
567 | ||
568 | // Return the value of the DW_AT_abstract_origin attribute. | |
569 | off_t | |
570 | abstract_origin() | |
571 | { | |
572 | if (!this->attributes_read_) | |
573 | this->read_attributes(); | |
574 | return this->abstract_origin_; | |
575 | } | |
576 | ||
577 | // Return the value of attribute ATTR as a string. | |
578 | const char* | |
579 | string_attribute(unsigned int attr); | |
580 | ||
581 | // Return the value of attribute ATTR as an integer. | |
582 | int64_t | |
583 | int_attribute(unsigned int attr); | |
584 | ||
585 | // Return the value of attribute ATTR as an unsigned integer. | |
586 | uint64_t | |
587 | uint_attribute(unsigned int attr); | |
588 | ||
589 | // Return the value of attribute ATTR as a reference. | |
590 | off_t | |
57923f48 MW |
591 | ref_attribute(unsigned int attr, unsigned int* shndx); |
592 | ||
593 | // Return the value of attribute ATTR as a address. | |
594 | off_t | |
595 | address_attribute(unsigned int attr, unsigned int* shndx); | |
c1027032 CC |
596 | |
597 | // Return the value of attribute ATTR as a flag. | |
598 | bool | |
599 | flag_attribute(unsigned int attr) | |
600 | { return this->int_attribute(attr) != 0; } | |
601 | ||
602 | // Return true if this DIE is a declaration. | |
603 | bool | |
604 | is_declaration() | |
605 | { return this->flag_attribute(elfcpp::DW_AT_declaration); } | |
606 | ||
607 | // Return the parent of this DIE. | |
608 | Dwarf_die* | |
609 | parent() const | |
610 | { return this->parent_; } | |
611 | ||
612 | // Return the offset of this DIE. | |
613 | off_t | |
614 | offset() const | |
615 | { return this->die_offset_; } | |
616 | ||
617 | // Return the offset of this DIE's first child. | |
618 | off_t | |
619 | child_offset(); | |
620 | ||
621 | // Set the offset of this DIE's next sibling. | |
622 | void | |
623 | set_sibling_offset(off_t sibling_offset) | |
624 | { this->sibling_offset_ = sibling_offset; } | |
625 | ||
626 | // Return the offset of this DIE's next sibling. | |
627 | off_t | |
628 | sibling_offset(); | |
629 | ||
630 | private: | |
631 | typedef Dwarf_abbrev_table::Abbrev_code Abbrev_code; | |
632 | ||
633 | // Read all the attributes of the DIE. | |
634 | bool | |
635 | read_attributes(); | |
636 | ||
637 | // Set the name of the DIE if present. | |
638 | void | |
639 | set_name(); | |
640 | ||
641 | // Set the linkage name if present. | |
642 | void | |
643 | set_linkage_name(); | |
644 | ||
645 | // Skip all the attributes of the DIE and return the offset | |
646 | // of the next DIE. | |
647 | off_t | |
648 | skip_attributes(); | |
649 | ||
650 | // The Dwarf_info_reader, for reading attributes. | |
651 | Dwarf_info_reader* dwinfo_; | |
652 | // The parent of this DIE. | |
653 | Dwarf_die* parent_; | |
654 | // Offset of this DIE within its compilation unit. | |
655 | off_t die_offset_; | |
656 | // Offset of the first attribute, relative to the beginning of the DIE. | |
657 | off_t attr_offset_; | |
658 | // Offset of the first child, relative to the compilation unit. | |
659 | off_t child_offset_; | |
660 | // Offset of the next sibling, relative to the compilation unit. | |
661 | off_t sibling_offset_; | |
662 | // The abbreviation table entry. | |
663 | const Abbrev_code* abbrev_code_; | |
664 | // The list of attributes. | |
665 | Attributes attributes_; | |
666 | // True if the attributes have been read. | |
667 | bool attributes_read_; | |
668 | // The following fields hold common attributes to avoid a linear | |
669 | // search through the attribute list. | |
670 | // The DIE name (DW_AT_name). | |
671 | const char* name_; | |
672 | // Offset of the name in the string table (for DW_FORM_strp). | |
673 | off_t name_off_; | |
674 | // The linkage name (DW_AT_linkage_name or DW_AT_MIPS_linkage_name). | |
675 | const char* linkage_name_; | |
676 | // Offset of the linkage name in the string table (for DW_FORM_strp). | |
677 | off_t linkage_name_off_; | |
678 | // Section index of the string table (for DW_FORM_strp). | |
679 | unsigned int string_shndx_; | |
680 | // The value of a DW_AT_specification attribute. | |
681 | off_t specification_; | |
682 | // The value of a DW_AT_abstract_origin attribute. | |
683 | off_t abstract_origin_; | |
684 | }; | |
685 | ||
686 | // This class is used to read the debug info from the .debug_info | |
687 | // or .debug_types sections. This is a base class that implements | |
688 | // the generic parsing of the compilation unit header and DIE | |
689 | // structure. The parse() method parses the entire section, and | |
690 | // calls the various visit_xxx() methods for each header. Clients | |
691 | // should derive a new class from this one and implement the | |
692 | // visit_compilation_unit() and visit_type_unit() functions. | |
693 | ||
694 | class Dwarf_info_reader | |
695 | { | |
696 | public: | |
697 | Dwarf_info_reader(bool is_type_unit, | |
698 | Relobj* object, | |
699 | const unsigned char* symtab, | |
700 | off_t symtab_size, | |
701 | unsigned int shndx, | |
702 | unsigned int reloc_shndx, | |
703 | unsigned int reloc_type) | |
704 | : is_type_unit_(is_type_unit), object_(object), symtab_(symtab), | |
705 | symtab_size_(symtab_size), shndx_(shndx), reloc_shndx_(reloc_shndx), | |
8787852d CC |
706 | reloc_type_(reloc_type), abbrev_shndx_(0), string_shndx_(0), |
707 | buffer_(NULL), buffer_end_(NULL), cu_offset_(0), cu_length_(0), | |
43819297 RM |
708 | offset_size_(0), address_size_(0), cu_version_(0), |
709 | abbrev_table_(), ranges_table_(this), | |
ed5d6712 | 710 | reloc_mapper_(NULL), string_buffer_(NULL), string_buffer_end_(NULL), |
8787852d | 711 | owns_string_buffer_(false), string_output_section_offset_(0) |
c1027032 CC |
712 | { } |
713 | ||
714 | virtual | |
715 | ~Dwarf_info_reader() | |
716 | { | |
717 | if (this->reloc_mapper_ != NULL) | |
718 | delete this->reloc_mapper_; | |
719 | if (this->owns_string_buffer_ && this->string_buffer_ != NULL) | |
720 | delete[] this->string_buffer_; | |
721 | } | |
722 | ||
723 | // Begin parsing the debug info. This calls visit_compilation_unit() | |
724 | // or visit_type_unit() for each compilation or type unit found in the | |
725 | // section, and visit_die() for each top-level DIE. | |
726 | void | |
727 | parse(); | |
728 | ||
729 | // Return the abbrev code entry for a CODE. | |
730 | const Dwarf_abbrev_table::Abbrev_code* | |
731 | get_abbrev(unsigned int code) | |
732 | { return this->abbrev_table_.get_abbrev(code); } | |
733 | ||
734 | // Return a pointer to the DWARF info buffer at OFFSET. | |
735 | const unsigned char* | |
736 | buffer_at_offset(off_t offset) const | |
737 | { | |
738 | const unsigned char* p = this->buffer_ + this->cu_offset_ + offset; | |
739 | if (this->check_buffer(p + 1)) | |
740 | return p; | |
741 | return NULL; | |
742 | } | |
743 | ||
ed5d6712 CC |
744 | // Read a possibly unaligned integer of SIZE. |
745 | template <int valsize> | |
746 | inline typename elfcpp::Valtype_base<valsize>::Valtype | |
747 | read_from_pointer(const unsigned char* source); | |
748 | ||
749 | // Read a possibly unaligned integer of SIZE. Update SOURCE after read. | |
750 | template <int valsize> | |
751 | inline typename elfcpp::Valtype_base<valsize>::Valtype | |
752 | read_from_pointer(const unsigned char** source); | |
753 | ||
c1027032 CC |
754 | // Look for a relocation at offset ATTR_OFF in the dwarf info, |
755 | // and return the section index and offset of the target. | |
756 | unsigned int | |
757 | lookup_reloc(off_t attr_off, off_t* target_off); | |
758 | ||
759 | // Return a string from the DWARF string table. | |
760 | const char* | |
761 | get_string(off_t str_off, unsigned int string_shndx); | |
762 | ||
763 | // Return the size of a DWARF offset. | |
764 | unsigned int | |
765 | offset_size() const | |
766 | { return this->offset_size_; } | |
767 | ||
768 | // Return the size of an address. | |
769 | unsigned int | |
770 | address_size() const | |
771 | { return this->address_size_; } | |
772 | ||
8787852d CC |
773 | // Set the section index of the .debug_abbrev section. |
774 | // We use this if there are no relocations for the .debug_info section. | |
775 | // If not set, the code parse() routine will search for the section by name. | |
776 | void | |
777 | set_abbrev_shndx(unsigned int abbrev_shndx) | |
778 | { this->abbrev_shndx_ = abbrev_shndx; } | |
779 | ||
234d4ab8 SA |
780 | // Return a pointer to the object file's ELF symbol table. |
781 | const unsigned char* | |
782 | symtab() const | |
783 | { return this->symtab_; } | |
784 | ||
785 | // Return the size of the object file's ELF symbol table. | |
786 | off_t | |
787 | symtab_size() const | |
788 | { return this->symtab_size_; } | |
789 | ||
790 | // Return the offset of the current compilation unit. | |
791 | off_t | |
792 | cu_offset() const | |
793 | { return this->cu_offset_; } | |
794 | ||
c1027032 CC |
795 | protected: |
796 | // Begin parsing the debug info. This calls visit_compilation_unit() | |
797 | // or visit_type_unit() for each compilation or type unit found in the | |
798 | // section, and visit_die() for each top-level DIE. | |
799 | template<bool big_endian> | |
800 | void | |
801 | do_parse(); | |
802 | ||
803 | // The following methods are hooks that are meant to be implemented | |
804 | // by a derived class. A default, do-nothing, implementation of | |
805 | // each is provided for this base class. | |
806 | ||
807 | // Visit a compilation unit. | |
808 | virtual void | |
809 | visit_compilation_unit(off_t cu_offset, off_t cu_length, Dwarf_die* root_die); | |
810 | ||
811 | // Visit a type unit. | |
812 | virtual void | |
908794a9 CC |
813 | visit_type_unit(off_t tu_offset, off_t tu_length, off_t type_offset, |
814 | uint64_t signature, Dwarf_die* root_die); | |
c1027032 CC |
815 | |
816 | // Read the range table. | |
817 | Dwarf_range_list* | |
818 | read_range_list(unsigned int ranges_shndx, off_t ranges_offset) | |
819 | { | |
820 | return this->ranges_table_.read_range_list(this->object_, | |
821 | this->symtab_, | |
822 | this->symtab_size_, | |
823 | this->address_size_, | |
824 | ranges_shndx, | |
825 | ranges_offset); | |
826 | } | |
827 | ||
828 | // Return the object. | |
829 | Relobj* | |
830 | object() const | |
831 | { return this->object_; } | |
832 | ||
c1027032 CC |
833 | // Checkpoint the relocation tracker. |
834 | uint64_t | |
835 | get_reloc_checkpoint() const | |
836 | { return this->reloc_mapper_->checkpoint(); } | |
837 | ||
838 | // Reset the relocation tracker to the CHECKPOINT. | |
839 | void | |
840 | reset_relocs(uint64_t checkpoint) | |
841 | { this->reloc_mapper_->reset(checkpoint); } | |
842 | ||
843 | private: | |
a68a081d CC |
844 | // Print a warning about a corrupt debug section. |
845 | void | |
846 | warn_corrupt_debug_section() const; | |
847 | ||
c1027032 CC |
848 | // Check that P is within the bounds of the current section. |
849 | bool | |
a68a081d CC |
850 | check_buffer(const unsigned char* p) const |
851 | { | |
852 | if (p > this->buffer_ + this->cu_offset_ + this->cu_length_) | |
853 | { | |
854 | this->warn_corrupt_debug_section(); | |
855 | return false; | |
856 | } | |
857 | return true; | |
858 | } | |
c1027032 CC |
859 | |
860 | // Read the DWARF string table. | |
861 | bool | |
862 | read_string_table(unsigned int string_shndx) | |
863 | { | |
864 | // If we've already read this string table, return immediately. | |
865 | if (this->string_shndx_ > 0 && this->string_shndx_ == string_shndx) | |
866 | return true; | |
867 | if (string_shndx == 0 && this->string_shndx_ > 0) | |
868 | return true; | |
869 | return this->do_read_string_table(string_shndx); | |
870 | } | |
871 | ||
872 | bool | |
873 | do_read_string_table(unsigned int string_shndx); | |
874 | ||
875 | // True if this is a type unit; false for a compilation unit. | |
876 | bool is_type_unit_; | |
877 | // The object containing the .debug_info or .debug_types input section. | |
878 | Relobj* object_; | |
879 | // The ELF symbol table. | |
880 | const unsigned char* symtab_; | |
881 | // The size of the ELF symbol table. | |
882 | off_t symtab_size_; | |
883 | // Index of the .debug_info or .debug_types section. | |
884 | unsigned int shndx_; | |
885 | // Index of the relocation section. | |
886 | unsigned int reloc_shndx_; | |
887 | // Type of the relocation section (SHT_REL or SHT_RELA). | |
888 | unsigned int reloc_type_; | |
8787852d CC |
889 | // Index of the .debug_abbrev section (0 if not known). |
890 | unsigned int abbrev_shndx_; | |
c1027032 CC |
891 | // Index of the .debug_str section. |
892 | unsigned int string_shndx_; | |
893 | // The buffer for the debug info. | |
894 | const unsigned char* buffer_; | |
895 | const unsigned char* buffer_end_; | |
896 | // Offset of the current compilation unit. | |
897 | off_t cu_offset_; | |
898 | // Length of the current compilation unit. | |
899 | off_t cu_length_; | |
900 | // Size of a DWARF offset for the current compilation unit. | |
901 | unsigned int offset_size_; | |
902 | // Size of an address for the target architecture. | |
903 | unsigned int address_size_; | |
904 | // Compilation unit version number. | |
905 | unsigned int cu_version_; | |
c1027032 CC |
906 | // Abbreviations table for current compilation unit. |
907 | Dwarf_abbrev_table abbrev_table_; | |
908 | // Ranges table for the current compilation unit. | |
909 | Dwarf_ranges_table ranges_table_; | |
910 | // Relocation mapper for the section. | |
911 | Elf_reloc_mapper* reloc_mapper_; | |
912 | // The buffer for the debug string table. | |
913 | const char* string_buffer_; | |
914 | const char* string_buffer_end_; | |
915 | // True if this object owns the buffer and needs to delete it. | |
916 | bool owns_string_buffer_; | |
917 | // For incremental update links, this will hold the offset of the | |
918 | // input .debug_str section within the output section. Offsets read | |
919 | // from relocated data will be relative to the output section, and need | |
920 | // to be corrected before reading data from the input section. | |
921 | uint64_t string_output_section_offset_; | |
922 | }; | |
923 | ||
79e052ea ILT |
924 | // We can't do better than to keep the offsets in a sorted vector. |
925 | // Here, offset is the key, and file_num/line_num is the value. | |
926 | struct Offset_to_lineno_entry | |
927 | { | |
928 | off_t offset; | |
929 | int header_num; // which file-list to use (i.e. which .o file are we in) | |
71ff8986 ILT |
930 | // A pointer into files_. |
931 | unsigned int file_num : sizeof(int) * CHAR_BIT - 1; | |
932 | // True if this was the last entry for the current offset, meaning | |
933 | // it's the line that actually applies. | |
934 | unsigned int last_line_for_offset : 1; | |
935 | // The line number in the source file. -1 to indicate end-of-function. | |
936 | int line_num; | |
937 | ||
938 | // This sorts by offsets first, and then puts the correct line to | |
939 | // report for a given offset at the beginning of the run of equal | |
940 | // offsets (so that asking for 1 line gives the best answer). This | |
941 | // is not a total ordering. | |
79e052ea | 942 | bool operator<(const Offset_to_lineno_entry& that) const |
71ff8986 ILT |
943 | { |
944 | if (this->offset != that.offset) | |
945 | return this->offset < that.offset; | |
946 | // Note the '>' which makes this sort 'true' first. | |
947 | return this->last_line_for_offset > that.last_line_for_offset; | |
948 | } | |
79e052ea ILT |
949 | }; |
950 | ||
5c2c6c95 ILT |
951 | // This class is used to read the line information from the debugging |
952 | // section of an object file. | |
953 | ||
954 | class Dwarf_line_info | |
955 | { | |
956 | public: | |
a55ce7fe ILT |
957 | Dwarf_line_info() |
958 | { } | |
959 | ||
960 | virtual | |
961 | ~Dwarf_line_info() | |
962 | { } | |
5c2c6c95 ILT |
963 | |
964 | // Given a section number and an offset, returns the associated | |
965 | // file and line-number, as a string: "file:lineno". If unable | |
966 | // to do the mapping, returns the empty string. You must call | |
71ff8986 ILT |
967 | // read_line_mappings() before calling this function. If |
968 | // 'other_lines' is non-NULL, fills that in with other line | |
969 | // numbers assigned to the same offset. | |
5c2c6c95 | 970 | std::string |
71ff8986 ILT |
971 | addr2line(unsigned int shndx, off_t offset, |
972 | std::vector<std::string>* other_lines) | |
973 | { return this->do_addr2line(shndx, offset, other_lines); } | |
a55ce7fe | 974 | |
e4e5049b CS |
975 | // A helper function for a single addr2line lookup. It also keeps a |
976 | // cache of the last CACHE_SIZE Dwarf_line_info objects it created; | |
977 | // set to 0 not to cache at all. The larger CACHE_SIZE is, the more | |
978 | // chance this routine won't have to re-create a Dwarf_line_info | |
979 | // object for its addr2line computation; such creations are slow. | |
980 | // NOTE: Not thread-safe, so only call from one thread at a time. | |
a55ce7fe | 981 | static std::string |
e4e5049b | 982 | one_addr2line(Object* object, unsigned int shndx, off_t offset, |
71ff8986 | 983 | size_t cache_size, std::vector<std::string>* other_lines); |
e4e5049b CS |
984 | |
985 | // This reclaims all the memory that one_addr2line may have cached. | |
986 | // Use this when you know you will not be calling one_addr2line again. | |
987 | static void | |
988 | clear_addr2line_cache(); | |
5c2c6c95 ILT |
989 | |
990 | private: | |
a55ce7fe | 991 | virtual std::string |
71ff8986 ILT |
992 | do_addr2line(unsigned int shndx, off_t offset, |
993 | std::vector<std::string>* other_lines) = 0; | |
a55ce7fe ILT |
994 | }; |
995 | ||
996 | template<int size, bool big_endian> | |
a18f2bd6 | 997 | class Sized_dwarf_line_info : public Dwarf_line_info |
a55ce7fe ILT |
998 | { |
999 | public: | |
1000 | // Initializes a .debug_line reader for a given object file. | |
9430daf8 ILT |
1001 | // If SHNDX is specified and non-negative, only read the debug |
1002 | // information that pertains to the specified section. | |
75aea3d0 | 1003 | Sized_dwarf_line_info(Object* object, unsigned int read_shndx = -1U); |
a55ce7fe | 1004 | |
5dd8762a CC |
1005 | virtual |
1006 | ~Sized_dwarf_line_info() | |
1007 | { | |
1008 | if (this->buffer_start_ != NULL) | |
1009 | delete[] this->buffer_start_; | |
1010 | } | |
1011 | ||
a55ce7fe ILT |
1012 | private: |
1013 | std::string | |
71ff8986 ILT |
1014 | do_addr2line(unsigned int shndx, off_t offset, |
1015 | std::vector<std::string>* other_lines); | |
1016 | ||
1017 | // Formats a file and line number to a string like "dirname/filename:lineno". | |
1018 | std::string | |
1019 | format_file_lineno(const Offset_to_lineno_entry& lineno) const; | |
a55ce7fe | 1020 | |
24badc65 | 1021 | // Start processing line info, and populates the offset_map_. |
9430daf8 ILT |
1022 | // If SHNDX is non-negative, only store debug information that |
1023 | // pertains to the specified section. | |
24badc65 | 1024 | void |
c1027032 | 1025 | read_line_mappings(unsigned int shndx); |
24badc65 | 1026 | |
4c50553d ILT |
1027 | // Reads the relocation section associated with .debug_line and |
1028 | // stores relocation information in reloc_map_. | |
1029 | void | |
c1027032 | 1030 | read_relocs(); |
4c50553d | 1031 | |
5c2c6c95 ILT |
1032 | // Reads the DWARF2/3 header for this line info. Each takes as input |
1033 | // a starting buffer position, and returns the ending position. | |
5c2c6c95 ILT |
1034 | const unsigned char* |
1035 | read_header_prolog(const unsigned char* lineptr); | |
1036 | ||
1037 | const unsigned char* | |
1038 | read_header_tables(const unsigned char* lineptr); | |
1039 | ||
9430daf8 ILT |
1040 | // Reads the DWARF2/3 line information. If shndx is non-negative, |
1041 | // discard all line information that doesn't pertain to the given | |
1042 | // section. | |
5c2c6c95 | 1043 | const unsigned char* |
75aea3d0 | 1044 | read_lines(const unsigned char* lineptr, unsigned int shndx); |
5c2c6c95 ILT |
1045 | |
1046 | // Process a single line info opcode at START using the state | |
1047 | // machine at LSM. Return true if we should define a line using the | |
1048 | // current state of the line state machine. Place the length of the | |
1049 | // opcode in LEN. | |
1050 | bool | |
e43872e9 | 1051 | process_one_opcode(const unsigned char* start, |
5c2c6c95 ILT |
1052 | struct LineStateMachine* lsm, size_t* len); |
1053 | ||
af674d1d ILT |
1054 | // Some parts of processing differ depending on whether the input |
1055 | // was a .o file or not. | |
1056 | bool input_is_relobj(); | |
1057 | ||
4c50553d ILT |
1058 | // If we saw anything amiss while parsing, we set this to false. |
1059 | // Then addr2line will always fail (rather than return possibly- | |
1060 | // corrupt data). | |
1061 | bool data_valid_; | |
1062 | ||
5c2c6c95 ILT |
1063 | // A DWARF2/3 line info header. This is not the same size as in the |
1064 | // actual file, as the one in the file may have a 32 bit or 64 bit | |
1065 | // lengths. | |
1066 | ||
1067 | struct Dwarf_line_infoHeader | |
1068 | { | |
1069 | off_t total_length; | |
1070 | int version; | |
1071 | off_t prologue_length; | |
1072 | int min_insn_length; // insn stands for instructin | |
1073 | bool default_is_stmt; // stmt stands for statement | |
1074 | signed char line_base; | |
1075 | int line_range; | |
1076 | unsigned char opcode_base; | |
1077 | std::vector<unsigned char> std_opcode_lengths; | |
1078 | int offset_size; | |
1079 | } header_; | |
1080 | ||
1081 | // buffer is the buffer for our line info, starting at exactly where | |
1082 | // the line info to read is. | |
1083 | const unsigned char* buffer_; | |
24badc65 | 1084 | const unsigned char* buffer_end_; |
5dd8762a CC |
1085 | // If the buffer was allocated temporarily, and therefore must be |
1086 | // deallocated in the dtor, this contains a pointer to the start | |
1087 | // of the buffer. | |
1088 | const unsigned char* buffer_start_; | |
5c2c6c95 | 1089 | |
4c50553d | 1090 | // This has relocations that point into buffer. |
c1027032 | 1091 | Sized_elf_reloc_mapper<size, big_endian>* reloc_mapper_; |
4dbfafcc ILT |
1092 | // The type of the reloc section in track_relocs_--SHT_REL or SHT_RELA. |
1093 | unsigned int track_relocs_type_; | |
4c50553d ILT |
1094 | |
1095 | // This is used to figure out what section to apply a relocation to. | |
24badc65 | 1096 | const unsigned char* symtab_buffer_; |
8383303e | 1097 | section_size_type symtab_buffer_size_; |
4c50553d | 1098 | |
af674d1d ILT |
1099 | // Holds the directories and files as we see them. We have an array |
1100 | // of directory-lists, one for each .o file we're reading (usually | |
1101 | // there will just be one, but there may be more if input is a .so). | |
1102 | std::vector<std::vector<std::string> > directories_; | |
5c2c6c95 | 1103 | // The first part is an index into directories_, the second the filename. |
af674d1d ILT |
1104 | std::vector<std::vector< std::pair<int, std::string> > > files_; |
1105 | ||
1106 | // An index into the current directories_ and files_ vectors. | |
1107 | int current_header_index_; | |
5c2c6c95 | 1108 | |
af674d1d ILT |
1109 | // A sorted map from offset of the relocation target to the shndx |
1110 | // and addend for the relocation. | |
c1027032 | 1111 | typedef std::map<off_t, std::pair<unsigned int, off_t> > |
4c50553d ILT |
1112 | Reloc_map; |
1113 | Reloc_map reloc_map_; | |
1114 | ||
5c2c6c95 ILT |
1115 | // We have a vector of offset->lineno entries for every input section. |
1116 | typedef Unordered_map<unsigned int, std::vector<Offset_to_lineno_entry> > | |
1117 | Lineno_map; | |
1118 | ||
1119 | Lineno_map line_number_map_; | |
1120 | }; | |
1121 | ||
1122 | } // End namespace gold. | |
1123 | ||
1124 | #endif // !defined(GOLD_DWARF_READER_H) |