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bae7f79e ILT |
1 | // symtab.h -- the gold symbol table -*- C++ -*- |
2 | ||
3 | // Symbol_table | |
4 | // The symbol table. | |
5 | ||
bae7f79e ILT |
6 | #include <string> |
7 | #include <utility> | |
ead1e424 | 8 | #include <vector> |
54dc6425 | 9 | #include <cassert> |
bae7f79e ILT |
10 | |
11 | #include "elfcpp.h" | |
14bfc3f5 | 12 | #include "stringpool.h" |
f6ce93d6 | 13 | #include "object.h" |
bae7f79e ILT |
14 | |
15 | #ifndef GOLD_SYMTAB_H | |
16 | #define GOLD_SYMTAB_H | |
17 | ||
18 | namespace gold | |
19 | { | |
20 | ||
14bfc3f5 | 21 | class Object; |
f6ce93d6 | 22 | class Relobj; |
dbe717ef ILT |
23 | template<int size, bool big_endian> |
24 | class Sized_relobj; | |
f6ce93d6 | 25 | class Dynobj; |
dbe717ef ILT |
26 | template<int size, bool big_endian> |
27 | class Sized_dynobj; | |
ead1e424 ILT |
28 | class Output_data; |
29 | class Output_segment; | |
61ba1cf9 ILT |
30 | class Output_file; |
31 | class Target; | |
14bfc3f5 | 32 | |
14bfc3f5 ILT |
33 | // The base class of an entry in the symbol table. The symbol table |
34 | // can have a lot of entries, so we don't want this class to big. | |
35 | // Size dependent fields can be found in the template class | |
36 | // Sized_symbol. Targets may support their own derived classes. | |
bae7f79e | 37 | |
bae7f79e ILT |
38 | class Symbol |
39 | { | |
40 | public: | |
ead1e424 ILT |
41 | // Because we want the class to be small, we don't use any virtual |
42 | // functions. But because symbols can be defined in different | |
43 | // places, we need to classify them. This enum is the different | |
44 | // sources of symbols we support. | |
45 | enum Source | |
46 | { | |
f6ce93d6 ILT |
47 | // Symbol defined in a relocatable or dynamic input file--this is |
48 | // the most common case. | |
ead1e424 ILT |
49 | FROM_OBJECT, |
50 | // Symbol defined in an Output_data, a special section created by | |
51 | // the target. | |
52 | IN_OUTPUT_DATA, | |
53 | // Symbol defined in an Output_segment, with no associated | |
54 | // section. | |
55 | IN_OUTPUT_SEGMENT, | |
56 | // Symbol value is constant. | |
57 | CONSTANT | |
58 | }; | |
59 | ||
60 | // When the source is IN_OUTPUT_SEGMENT, we need to describe what | |
61 | // the offset means. | |
62 | enum Segment_offset_base | |
63 | { | |
64 | // From the start of the segment. | |
65 | SEGMENT_START, | |
66 | // From the end of the segment. | |
67 | SEGMENT_END, | |
68 | // From the filesz of the segment--i.e., after the loaded bytes | |
69 | // but before the bytes which are allocated but zeroed. | |
70 | SEGMENT_BSS | |
71 | }; | |
72 | ||
14bfc3f5 ILT |
73 | // Return the symbol name. |
74 | const char* | |
75 | name() const | |
76 | { return this->name_; } | |
77 | ||
78 | // Return the symbol version. This will return NULL for an | |
79 | // unversioned symbol. | |
80 | const char* | |
81 | version() const | |
82 | { return this->version_; } | |
83 | ||
ead1e424 ILT |
84 | // Return the symbol source. |
85 | Source | |
86 | source() const | |
87 | { return this->source_; } | |
88 | ||
14bfc3f5 ILT |
89 | // Return the object with which this symbol is associated. |
90 | Object* | |
91 | object() const | |
ead1e424 ILT |
92 | { |
93 | assert(this->source_ == FROM_OBJECT); | |
94 | return this->u_.from_object.object; | |
95 | } | |
96 | ||
f6ce93d6 ILT |
97 | // Return the index of the section in the input relocatable or |
98 | // dynamic object file. | |
ead1e424 ILT |
99 | unsigned int |
100 | shnum() const | |
101 | { | |
102 | assert(this->source_ == FROM_OBJECT); | |
103 | return this->u_.from_object.shnum; | |
104 | } | |
105 | ||
106 | // Return the output data section with which this symbol is | |
107 | // associated, if the symbol was specially defined with respect to | |
108 | // an output data section. | |
109 | Output_data* | |
110 | output_data() const | |
111 | { | |
112 | assert(this->source_ == IN_OUTPUT_DATA); | |
113 | return this->u_.in_output_data.output_data; | |
114 | } | |
115 | ||
116 | // If this symbol was defined with respect to an output data | |
117 | // section, return whether the value is an offset from end. | |
118 | bool | |
119 | offset_is_from_end() const | |
120 | { | |
121 | assert(this->source_ == IN_OUTPUT_DATA); | |
122 | return this->u_.in_output_data.offset_is_from_end; | |
123 | } | |
124 | ||
125 | // Return the output segment with which this symbol is associated, | |
126 | // if the symbol was specially defined with respect to an output | |
127 | // segment. | |
128 | Output_segment* | |
129 | output_segment() const | |
130 | { | |
131 | assert(this->source_ == IN_OUTPUT_SEGMENT); | |
132 | return this->u_.in_output_segment.output_segment; | |
133 | } | |
134 | ||
135 | // If this symbol was defined with respect to an output segment, | |
136 | // return the offset base. | |
137 | Segment_offset_base | |
138 | offset_base() const | |
139 | { | |
140 | assert(this->source_ == IN_OUTPUT_SEGMENT); | |
141 | return this->u_.in_output_segment.offset_base; | |
142 | } | |
14bfc3f5 ILT |
143 | |
144 | // Return the symbol binding. | |
145 | elfcpp::STB | |
146 | binding() const | |
147 | { return this->binding_; } | |
148 | ||
1564db8d ILT |
149 | // Return the symbol type. |
150 | elfcpp::STT | |
151 | type() const | |
152 | { return this->type_; } | |
153 | ||
154 | // Return the symbol visibility. | |
155 | elfcpp::STV | |
156 | visibility() const | |
157 | { return this->visibility_; } | |
158 | ||
159 | // Return the non-visibility part of the st_other field. | |
160 | unsigned char | |
ead1e424 ILT |
161 | nonvis() const |
162 | { return this->nonvis_; } | |
14bfc3f5 | 163 | |
1564db8d ILT |
164 | // Return whether this symbol is a forwarder. This will never be |
165 | // true of a symbol found in the hash table, but may be true of | |
166 | // symbol pointers attached to object files. | |
167 | bool | |
168 | is_forwarder() const | |
169 | { return this->is_forwarder_; } | |
170 | ||
171 | // Mark this symbol as a forwarder. | |
172 | void | |
173 | set_forwarder() | |
174 | { this->is_forwarder_ = true; } | |
175 | ||
f6ce93d6 | 176 | // Return whether this symbol was ever seen in a dynamic object. |
1564db8d ILT |
177 | bool |
178 | in_dyn() const | |
179 | { return this->in_dyn_; } | |
180 | ||
f6ce93d6 | 181 | // Mark this symbol as having been seen in a dynamic object. |
1564db8d ILT |
182 | void |
183 | set_in_dyn() | |
184 | { this->in_dyn_ = true; } | |
185 | ||
ead1e424 | 186 | // Return whether this symbol has an entry in the GOT section. |
92e059d8 | 187 | bool |
ead1e424 ILT |
188 | has_got_offset() const |
189 | { return this->has_got_offset_; } | |
190 | ||
191 | // Return the offset into the GOT section of this symbol. | |
192 | unsigned int | |
193 | got_offset() const | |
194 | { | |
195 | assert(this->has_got_offset()); | |
196 | return this->got_offset_; | |
197 | } | |
198 | ||
199 | // Set the GOT offset of this symbol. | |
200 | void | |
201 | set_got_offset(unsigned int got_offset) | |
202 | { | |
203 | this->has_got_offset_ = true; | |
204 | this->got_offset_ = got_offset; | |
205 | } | |
206 | ||
207 | // Return whether this symbol is resolved locally. This is always | |
208 | // true when linking statically. It is true for a symbol defined in | |
209 | // this object when using -Bsymbolic. It is true for a symbol | |
210 | // marked local in a version file. FIXME: This needs to be | |
211 | // completed. | |
212 | bool | |
213 | is_resolved_locally() const | |
214 | { return !this->in_dyn_; } | |
215 | ||
f6ce93d6 ILT |
216 | // Return whether this is a defined symbol (not undefined or |
217 | // common). | |
218 | bool | |
219 | is_defined() const | |
220 | { | |
221 | return (this->source_ != FROM_OBJECT | |
222 | || (this->u_.from_object.shnum != elfcpp::SHN_UNDEF | |
223 | && this->u_.from_object.shnum != elfcpp::SHN_COMMON)); | |
224 | } | |
225 | ||
ead1e424 ILT |
226 | // Return whether this is an undefined symbol. |
227 | bool | |
228 | is_undefined() const | |
229 | { | |
230 | return this->source_ == FROM_OBJECT && this->shnum() == elfcpp::SHN_UNDEF; | |
231 | } | |
232 | ||
233 | // Return whether this is a common symbol. | |
234 | bool | |
235 | is_common() const | |
236 | { | |
f6ce93d6 ILT |
237 | return (this->source_ == FROM_OBJECT |
238 | && (this->u_.from_object.shnum == elfcpp::SHN_COMMON | |
239 | || this->type_ == elfcpp::STT_COMMON)); | |
ead1e424 | 240 | } |
92e059d8 | 241 | |
f6ce93d6 ILT |
242 | // Return whether there should be a warning for references to this |
243 | // symbol. | |
244 | bool | |
245 | has_warning() const | |
246 | { return this->has_warning_; } | |
247 | ||
248 | // Mark this symbol as having a warning. | |
249 | void | |
250 | set_has_warning() | |
251 | { this->has_warning_ = true; } | |
252 | ||
14bfc3f5 ILT |
253 | protected: |
254 | // Instances of this class should always be created at a specific | |
255 | // size. | |
256 | Symbol() | |
f6ce93d6 | 257 | { memset(this, 0, sizeof *this); } |
14bfc3f5 | 258 | |
ead1e424 ILT |
259 | // Initialize the general fields. |
260 | void | |
261 | init_fields(const char* name, const char* version, | |
262 | elfcpp::STT type, elfcpp::STB binding, | |
263 | elfcpp::STV visibility, unsigned char nonvis); | |
264 | ||
14bfc3f5 ILT |
265 | // Initialize fields from an ELF symbol in OBJECT. |
266 | template<int size, bool big_endian> | |
267 | void | |
268 | init_base(const char *name, const char* version, Object* object, | |
269 | const elfcpp::Sym<size, big_endian>&); | |
bae7f79e | 270 | |
ead1e424 ILT |
271 | // Initialize fields for an Output_data. |
272 | void | |
273 | init_base(const char* name, Output_data*, elfcpp::STT, elfcpp::STB, | |
274 | elfcpp::STV, unsigned char nonvis, bool offset_is_from_end); | |
275 | ||
276 | // Initialize fields for an Output_segment. | |
277 | void | |
278 | init_base(const char* name, Output_segment* os, elfcpp::STT type, | |
279 | elfcpp::STB binding, elfcpp::STV visibility, | |
280 | unsigned char nonvis, Segment_offset_base offset_base); | |
281 | ||
282 | // Initialize fields for a constant. | |
283 | void | |
284 | init_base(const char* name, elfcpp::STT type, elfcpp::STB binding, | |
285 | elfcpp::STV visibility, unsigned char nonvis); | |
286 | ||
1564db8d ILT |
287 | // Override existing symbol. |
288 | template<int size, bool big_endian> | |
289 | void | |
290 | override_base(const elfcpp::Sym<size, big_endian>&, Object* object); | |
291 | ||
bae7f79e | 292 | private: |
14bfc3f5 ILT |
293 | Symbol(const Symbol&); |
294 | Symbol& operator=(const Symbol&); | |
295 | ||
296 | // Symbol name (expected to point into a Stringpool). | |
297 | const char* name_; | |
298 | // Symbol version (expected to point into a Stringpool). This may | |
299 | // be NULL. | |
bae7f79e | 300 | const char* version_; |
ead1e424 ILT |
301 | |
302 | union | |
303 | { | |
304 | // This struct is used if SOURCE_ == FROM_OBJECT. | |
305 | struct | |
306 | { | |
307 | // Object in which symbol is defined, or in which it was first | |
308 | // seen. | |
309 | Object* object; | |
310 | // Section number in object_ in which symbol is defined. | |
311 | unsigned int shnum; | |
312 | } from_object; | |
313 | ||
314 | // This struct is used if SOURCE_ == IN_OUTPUT_DATA. | |
315 | struct | |
316 | { | |
317 | // Output_data in which symbol is defined. Before | |
318 | // Layout::finalize the symbol's value is an offset within the | |
319 | // Output_data. | |
320 | Output_data* output_data; | |
321 | // True if the offset is from the end, false if the offset is | |
322 | // from the beginning. | |
323 | bool offset_is_from_end; | |
324 | } in_output_data; | |
325 | ||
326 | // This struct is used if SOURCE_ == IN_OUTPUT_SEGMENT. | |
327 | struct | |
328 | { | |
329 | // Output_segment in which the symbol is defined. Before | |
330 | // Layout::finalize the symbol's value is an offset. | |
331 | Output_segment* output_segment; | |
332 | // The base to use for the offset before Layout::finalize. | |
333 | Segment_offset_base offset_base; | |
334 | } in_output_segment; | |
335 | } u_; | |
336 | ||
337 | // If this symbol has an entry in the GOT section (has_got_offset_ | |
338 | // is true), this is the offset. | |
339 | unsigned int got_offset_; | |
14bfc3f5 | 340 | // Symbol type. |
bae7f79e | 341 | elfcpp::STT type_ : 4; |
14bfc3f5 | 342 | // Symbol binding. |
bae7f79e | 343 | elfcpp::STB binding_ : 4; |
14bfc3f5 ILT |
344 | // Symbol visibility. |
345 | elfcpp::STV visibility_ : 2; | |
346 | // Rest of symbol st_other field. | |
ead1e424 ILT |
347 | unsigned int nonvis_ : 6; |
348 | // The type of symbol. | |
f6ce93d6 | 349 | Source source_ : 3; |
14bfc3f5 ILT |
350 | // True if this symbol always requires special target-specific |
351 | // handling. | |
ead1e424 | 352 | bool is_target_special_ : 1; |
14bfc3f5 | 353 | // True if this is the default version of the symbol. |
1564db8d | 354 | bool is_def_ : 1; |
14bfc3f5 ILT |
355 | // True if this symbol really forwards to another symbol. This is |
356 | // used when we discover after the fact that two different entries | |
357 | // in the hash table really refer to the same symbol. This will | |
358 | // never be set for a symbol found in the hash table, but may be set | |
359 | // for a symbol found in the list of symbols attached to an Object. | |
360 | // It forwards to the symbol found in the forwarders_ map of | |
361 | // Symbol_table. | |
1564db8d ILT |
362 | bool is_forwarder_ : 1; |
363 | // True if we've seen this symbol in a dynamic object. | |
364 | bool in_dyn_ : 1; | |
ead1e424 ILT |
365 | // True if the symbol has an entry in the GOT section. |
366 | bool has_got_offset_ : 1; | |
f6ce93d6 ILT |
367 | // True if there is a warning for this symbol. |
368 | bool has_warning_ : 1; | |
bae7f79e ILT |
369 | }; |
370 | ||
14bfc3f5 ILT |
371 | // The parts of a symbol which are size specific. Using a template |
372 | // derived class like this helps us use less space on a 32-bit system. | |
bae7f79e ILT |
373 | |
374 | template<int size> | |
14bfc3f5 ILT |
375 | class Sized_symbol : public Symbol |
376 | { | |
377 | public: | |
1564db8d ILT |
378 | typedef typename elfcpp::Elf_types<size>::Elf_Addr Value_type; |
379 | typedef typename elfcpp::Elf_types<size>::Elf_WXword Size_type; | |
380 | ||
14bfc3f5 ILT |
381 | Sized_symbol() |
382 | { } | |
383 | ||
384 | // Initialize fields from an ELF symbol in OBJECT. | |
385 | template<bool big_endian> | |
386 | void | |
387 | init(const char *name, const char* version, Object* object, | |
388 | const elfcpp::Sym<size, big_endian>&); | |
389 | ||
ead1e424 ILT |
390 | // Initialize fields for an Output_data. |
391 | void | |
392 | init(const char* name, Output_data*, Value_type value, Size_type symsize, | |
393 | elfcpp::STT, elfcpp::STB, elfcpp::STV, unsigned char nonvis, | |
394 | bool offset_is_from_end); | |
395 | ||
396 | // Initialize fields for an Output_segment. | |
397 | void | |
398 | init(const char* name, Output_segment*, Value_type value, Size_type symsize, | |
399 | elfcpp::STT, elfcpp::STB, elfcpp::STV, unsigned char nonvis, | |
400 | Segment_offset_base offset_base); | |
401 | ||
402 | // Initialize fields for a constant. | |
403 | void | |
404 | init(const char* name, Value_type value, Size_type symsize, | |
405 | elfcpp::STT, elfcpp::STB, elfcpp::STV, unsigned char nonvis); | |
406 | ||
1564db8d ILT |
407 | // Override existing symbol. |
408 | template<bool big_endian> | |
409 | void | |
410 | override(const elfcpp::Sym<size, big_endian>&, Object* object); | |
411 | ||
412 | // Return the symbol's value. | |
413 | Value_type | |
414 | value() const | |
415 | { return this->value_; } | |
416 | ||
417 | // Return the symbol's size (we can't call this 'size' because that | |
418 | // is a template parameter). | |
419 | Size_type | |
420 | symsize() const | |
ead1e424 ILT |
421 | { return this->symsize_; } |
422 | ||
423 | // Set the symbol size. This is used when resolving common symbols. | |
424 | void | |
425 | set_symsize(Size_type symsize) | |
426 | { this->symsize_ = symsize; } | |
1564db8d | 427 | |
75f65a3e ILT |
428 | // Set the symbol value. This is called when we store the final |
429 | // values of the symbols into the symbol table. | |
430 | void | |
431 | set_value(Value_type value) | |
432 | { this->value_ = value; } | |
433 | ||
14bfc3f5 ILT |
434 | private: |
435 | Sized_symbol(const Sized_symbol&); | |
436 | Sized_symbol& operator=(const Sized_symbol&); | |
437 | ||
ead1e424 ILT |
438 | // Symbol value. Before Layout::finalize this is the offset in the |
439 | // input section. This is set to the final value during | |
440 | // Layout::finalize. | |
1564db8d | 441 | Value_type value_; |
14bfc3f5 | 442 | // Symbol size. |
ead1e424 ILT |
443 | Size_type symsize_; |
444 | }; | |
445 | ||
446 | // A struct describing a symbol defined by the linker, where the value | |
447 | // of the symbol is defined based on an output section. This is used | |
448 | // for symbols defined by the linker, like "_init_array_start". | |
449 | ||
450 | struct Define_symbol_in_section | |
451 | { | |
452 | // The symbol name. | |
453 | const char* name; | |
454 | // The name of the output section with which this symbol should be | |
455 | // associated. If there is no output section with that name, the | |
456 | // symbol will be defined as zero. | |
457 | const char* output_section; | |
458 | // The offset of the symbol within the output section. This is an | |
459 | // offset from the start of the output section, unless start_at_end | |
460 | // is true, in which case this is an offset from the end of the | |
461 | // output section. | |
462 | uint64_t value; | |
463 | // The size of the symbol. | |
464 | uint64_t size; | |
465 | // The symbol type. | |
466 | elfcpp::STT type; | |
467 | // The symbol binding. | |
468 | elfcpp::STB binding; | |
469 | // The symbol visibility. | |
470 | elfcpp::STV visibility; | |
471 | // The rest of the st_other field. | |
472 | unsigned char nonvis; | |
473 | // If true, the value field is an offset from the end of the output | |
474 | // section. | |
475 | bool offset_is_from_end; | |
476 | // If true, this symbol is defined only if we see a reference to it. | |
477 | bool only_if_ref; | |
478 | }; | |
479 | ||
480 | // A struct describing a symbol defined by the linker, where the value | |
481 | // of the symbol is defined based on a segment. This is used for | |
482 | // symbols defined by the linker, like "_end". We describe the | |
483 | // segment with which the symbol should be associated by its | |
484 | // characteristics. If no segment meets these characteristics, the | |
485 | // symbol will be defined as zero. If there is more than one segment | |
486 | // which meets these characteristics, we will use the first one. | |
487 | ||
488 | struct Define_symbol_in_segment | |
489 | { | |
490 | // The symbol name. | |
491 | const char* name; | |
492 | // The segment type where the symbol should be defined, typically | |
493 | // PT_LOAD. | |
494 | elfcpp::PT segment_type; | |
495 | // Bitmask of segment flags which must be set. | |
496 | elfcpp::PF segment_flags_set; | |
497 | // Bitmask of segment flags which must be clear. | |
498 | elfcpp::PF segment_flags_clear; | |
499 | // The offset of the symbol within the segment. The offset is | |
500 | // calculated from the position set by offset_base. | |
501 | uint64_t value; | |
502 | // The size of the symbol. | |
503 | uint64_t size; | |
504 | // The symbol type. | |
505 | elfcpp::STT type; | |
506 | // The symbol binding. | |
507 | elfcpp::STB binding; | |
508 | // The symbol visibility. | |
509 | elfcpp::STV visibility; | |
510 | // The rest of the st_other field. | |
511 | unsigned char nonvis; | |
512 | // The base from which we compute the offset. | |
513 | Symbol::Segment_offset_base offset_base; | |
514 | // If true, this symbol is defined only if we see a reference to it. | |
515 | bool only_if_ref; | |
14bfc3f5 ILT |
516 | }; |
517 | ||
f6ce93d6 ILT |
518 | // This class manages warnings. Warnings are a GNU extension. When |
519 | // we see a section named .gnu.warning.SYM in an object file, and if | |
520 | // we wind using the definition of SYM from that object file, then we | |
521 | // will issue a warning for any relocation against SYM from a | |
522 | // different object file. The text of the warning is the contents of | |
523 | // the section. This is not precisely the definition used by the old | |
524 | // GNU linker; the old GNU linker treated an occurrence of | |
525 | // .gnu.warning.SYM as defining a warning symbol. A warning symbol | |
526 | // would trigger a warning on any reference. However, it was | |
527 | // inconsistent in that a warning in a dynamic object only triggered | |
528 | // if there was no definition in a regular object. This linker is | |
529 | // different in that we only issue a warning if we use the symbol | |
530 | // definition from the same object file as the warning section. | |
531 | ||
532 | class Warnings | |
533 | { | |
534 | public: | |
535 | Warnings() | |
536 | : warnings_() | |
537 | { } | |
538 | ||
539 | // Add a warning for symbol NAME in section SHNDX in object OBJ. | |
540 | void | |
541 | add_warning(Symbol_table* symtab, const char* name, Object* obj, | |
542 | unsigned int shndx); | |
543 | ||
544 | // For each symbol for which we should give a warning, make a note | |
545 | // on the symbol. | |
546 | void | |
547 | note_warnings(Symbol_table* symtab); | |
548 | ||
549 | // Issue a warning for a reference to SYM at LOCATION. | |
550 | void | |
551 | issue_warning(Symbol* sym, const std::string& location) const; | |
552 | ||
553 | private: | |
554 | Warnings(const Warnings&); | |
555 | Warnings& operator=(const Warnings&); | |
556 | ||
557 | // What we need to know to get the warning text. | |
558 | struct Warning_location | |
559 | { | |
560 | // The object the warning is in. | |
561 | Object* object; | |
562 | // The index of the warning section. | |
563 | unsigned int shndx; | |
564 | // The warning text if we have already loaded it. | |
565 | std::string text; | |
566 | ||
567 | Warning_location() | |
568 | : object(NULL), shndx(0), text() | |
569 | { } | |
570 | ||
571 | void | |
572 | set(Object* o, unsigned int s) | |
573 | { | |
574 | this->object = o; | |
575 | this->shndx = s; | |
576 | } | |
577 | ||
578 | void | |
579 | set_text(const char* t, off_t l) | |
580 | { this->text.assign(t, l); } | |
581 | }; | |
582 | ||
583 | // A mapping from warning symbol names (canonicalized in | |
584 | // Symbol_table's namepool_ field) to | |
585 | typedef Unordered_map<const char*, Warning_location> Warning_table; | |
586 | ||
587 | Warning_table warnings_; | |
588 | }; | |
589 | ||
14bfc3f5 ILT |
590 | // The main linker symbol table. |
591 | ||
bae7f79e ILT |
592 | class Symbol_table |
593 | { | |
594 | public: | |
595 | Symbol_table(); | |
596 | ||
1564db8d | 597 | ~Symbol_table(); |
bae7f79e | 598 | |
dbe717ef | 599 | // Add COUNT external symbols from the relocatable object RELOBJ to |
f6ce93d6 ILT |
600 | // the symbol table. SYMS is the symbols, SYM_NAMES is their names, |
601 | // SYM_NAME_SIZE is the size of SYM_NAMES. This sets SYMPOINTERS to | |
602 | // point to the symbols in the symbol table. | |
14bfc3f5 ILT |
603 | template<int size, bool big_endian> |
604 | void | |
dbe717ef ILT |
605 | add_from_relobj(Sized_relobj<size, big_endian>* relobj, |
606 | const unsigned char* syms, size_t count, | |
607 | const char* sym_names, size_t sym_name_size, | |
14bfc3f5 ILT |
608 | Symbol** sympointers); |
609 | ||
dbe717ef ILT |
610 | // Add COUNT dynamic symbols from the dynamic object DYNOBJ to the |
611 | // symbol table. SYMS is the symbols. SYM_NAMES is their names. | |
612 | // SYM_NAME_SIZE is the size of SYM_NAMES. The other parameters are | |
613 | // symbol version data. | |
614 | template<int size, bool big_endian> | |
615 | void | |
616 | add_from_dynobj(Sized_dynobj<size, big_endian>* dynobj, | |
617 | const unsigned char* syms, size_t count, | |
618 | const char* sym_names, size_t sym_name_size, | |
619 | const unsigned char* versym, size_t versym_size, | |
620 | const std::vector<const char*>*); | |
621 | ||
ead1e424 ILT |
622 | // Define a special symbol. |
623 | template<int size, bool big_endian> | |
624 | Sized_symbol<size>* | |
593f47df ILT |
625 | define_special_symbol(Target* target, const char* name, bool only_if_ref |
626 | ACCEPT_SIZE_ENDIAN); | |
ead1e424 ILT |
627 | |
628 | // Define a special symbol based on an Output_data. It is a | |
629 | // multiple definition error if this symbol is already defined. | |
630 | void | |
631 | define_in_output_data(Target*, const char* name, Output_data*, | |
632 | uint64_t value, uint64_t symsize, | |
633 | elfcpp::STT type, elfcpp::STB binding, | |
634 | elfcpp::STV visibility, unsigned char nonvis, | |
635 | bool offset_is_from_end, bool only_if_ref); | |
636 | ||
637 | // Define a special symbol based on an Output_segment. It is a | |
638 | // multiple definition error if this symbol is already defined. | |
639 | void | |
640 | define_in_output_segment(Target*, const char* name, Output_segment*, | |
641 | uint64_t value, uint64_t symsize, | |
642 | elfcpp::STT type, elfcpp::STB binding, | |
643 | elfcpp::STV visibility, unsigned char nonvis, | |
644 | Symbol::Segment_offset_base, bool only_if_ref); | |
645 | ||
646 | // Define a special symbol with a constant value. It is a multiple | |
647 | // definition error if this symbol is already defined. | |
648 | void | |
649 | define_as_constant(Target*, const char* name, uint64_t value, | |
650 | uint64_t symsize, elfcpp::STT type, elfcpp::STB binding, | |
651 | elfcpp::STV visibility, unsigned char nonvis, | |
652 | bool only_if_ref); | |
653 | ||
654 | // Define a set of symbols in output sections. | |
655 | void | |
656 | define_symbols(const Layout*, Target*, int count, | |
657 | const Define_symbol_in_section*); | |
658 | ||
659 | // Define a set of symbols in output segments. | |
660 | void | |
661 | define_symbols(const Layout*, Target*, int count, | |
662 | const Define_symbol_in_segment*); | |
663 | ||
61ba1cf9 ILT |
664 | // Look up a symbol. |
665 | Symbol* | |
666 | lookup(const char*, const char* version = NULL) const; | |
667 | ||
14bfc3f5 | 668 | // Return the real symbol associated with the forwarder symbol FROM. |
bae7f79e | 669 | Symbol* |
14bfc3f5 | 670 | resolve_forwards(Symbol* from) const; |
bae7f79e | 671 | |
14bfc3f5 ILT |
672 | // Return the size of the symbols in the table. |
673 | int | |
674 | get_size() const | |
675 | { return this->size_; } | |
bae7f79e | 676 | |
1564db8d ILT |
677 | // Return the sized version of a symbol in this table. |
678 | template<int size> | |
679 | Sized_symbol<size>* | |
5482377d | 680 | get_sized_symbol(Symbol* ACCEPT_SIZE) const; |
1564db8d ILT |
681 | |
682 | template<int size> | |
683 | const Sized_symbol<size>* | |
5482377d | 684 | get_sized_symbol(const Symbol* ACCEPT_SIZE) const; |
54dc6425 | 685 | |
ead1e424 ILT |
686 | // Return the count of undefined symbols seen. |
687 | int | |
688 | saw_undefined() const | |
689 | { return this->saw_undefined_; } | |
690 | ||
691 | // Allocate the common symbols | |
692 | void | |
693 | allocate_commons(const General_options&, Layout*); | |
694 | ||
f6ce93d6 ILT |
695 | // Add a warning for symbol NAME in section SHNDX in object OBJ. |
696 | void | |
697 | add_warning(const char* name, Object* obj, unsigned int shndx) | |
698 | { this->warnings_.add_warning(this, name, obj, shndx); } | |
699 | ||
700 | // Canonicalize a symbol name for use in the hash table. | |
701 | const char* | |
702 | canonicalize_name(const char* name) | |
f0641a0b | 703 | { return this->namepool_.add(name, NULL); } |
f6ce93d6 ILT |
704 | |
705 | // Possibly issue a warning for a reference to SYM at LOCATION which | |
706 | // is in OBJ. | |
707 | void | |
708 | issue_warning(Symbol* sym, const std::string& location) const | |
709 | { this->warnings_.issue_warning(sym, location); } | |
710 | ||
75f65a3e ILT |
711 | // Finalize the symbol table after we have set the final addresses |
712 | // of all the input sections. This sets the final symbol values and | |
713 | // adds the names to *POOL. It records the file offset OFF, and | |
714 | // returns the new file offset. | |
715 | off_t | |
716 | finalize(off_t, Stringpool*); | |
1564db8d | 717 | |
61ba1cf9 ILT |
718 | // Write out the global symbols. |
719 | void | |
720 | write_globals(const Target*, const Stringpool*, Output_file*) const; | |
721 | ||
bae7f79e ILT |
722 | private: |
723 | Symbol_table(const Symbol_table&); | |
724 | Symbol_table& operator=(const Symbol_table&); | |
725 | ||
14bfc3f5 ILT |
726 | // Set the size of the symbols in the table. |
727 | void | |
728 | set_size(int size) | |
729 | { this->size_ = size; } | |
730 | ||
731 | // Make FROM a forwarder symbol to TO. | |
732 | void | |
733 | make_forwarder(Symbol* from, Symbol* to); | |
734 | ||
735 | // Add a symbol. | |
736 | template<int size, bool big_endian> | |
737 | Symbol* | |
f0641a0b ILT |
738 | add_from_object(Object*, const char *name, Stringpool::Key name_key, |
739 | const char *version, Stringpool::Key version_key, | |
740 | bool def, const elfcpp::Sym<size, big_endian>& sym); | |
14bfc3f5 ILT |
741 | |
742 | // Resolve symbols. | |
743 | template<int size, bool big_endian> | |
744 | static void | |
1564db8d ILT |
745 | resolve(Sized_symbol<size>* to, |
746 | const elfcpp::Sym<size, big_endian>& sym, | |
747 | Object*); | |
14bfc3f5 | 748 | |
1564db8d | 749 | template<int size, bool big_endian> |
14bfc3f5 | 750 | static void |
5482377d ILT |
751 | resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from |
752 | ACCEPT_SIZE_ENDIAN); | |
14bfc3f5 | 753 | |
ead1e424 ILT |
754 | // Define a symbol in an Output_data, sized version. |
755 | template<int size> | |
756 | void | |
757 | do_define_in_output_data(Target*, const char* name, Output_data*, | |
758 | typename elfcpp::Elf_types<size>::Elf_Addr value, | |
759 | typename elfcpp::Elf_types<size>::Elf_WXword ssize, | |
760 | elfcpp::STT type, elfcpp::STB binding, | |
761 | elfcpp::STV visibility, unsigned char nonvis, | |
762 | bool offset_is_from_end, bool only_if_ref); | |
763 | ||
764 | // Define a symbol in an Output_segment, sized version. | |
765 | template<int size> | |
766 | void | |
767 | do_define_in_output_segment( | |
768 | Target*, const char* name, Output_segment* os, | |
769 | typename elfcpp::Elf_types<size>::Elf_Addr value, | |
770 | typename elfcpp::Elf_types<size>::Elf_WXword ssize, | |
771 | elfcpp::STT type, elfcpp::STB binding, | |
772 | elfcpp::STV visibility, unsigned char nonvis, | |
773 | Symbol::Segment_offset_base offset_base, bool only_if_ref); | |
774 | ||
775 | // Define a symbol as a constant, sized version. | |
776 | template<int size> | |
777 | void | |
778 | do_define_as_constant( | |
779 | Target*, const char* name, | |
780 | typename elfcpp::Elf_types<size>::Elf_Addr value, | |
781 | typename elfcpp::Elf_types<size>::Elf_WXword ssize, | |
782 | elfcpp::STT type, elfcpp::STB binding, | |
783 | elfcpp::STV visibility, unsigned char nonvis, | |
784 | bool only_if_ref); | |
785 | ||
786 | // Allocate the common symbols, sized version. | |
787 | template<int size> | |
788 | void | |
789 | do_allocate_commons(const General_options&, Layout*); | |
790 | ||
75f65a3e ILT |
791 | // Finalize symbols specialized for size. |
792 | template<int size> | |
793 | off_t | |
794 | sized_finalize(off_t, Stringpool*); | |
795 | ||
61ba1cf9 ILT |
796 | // Write globals specialized for size and endianness. |
797 | template<int size, bool big_endian> | |
798 | void | |
799 | sized_write_globals(const Target*, const Stringpool*, Output_file*) const; | |
800 | ||
54dc6425 ILT |
801 | // The type of the symbol hash table. |
802 | ||
f0641a0b | 803 | typedef std::pair<Stringpool::Key, Stringpool::Key> Symbol_table_key; |
14bfc3f5 ILT |
804 | |
805 | struct Symbol_table_hash | |
806 | { | |
807 | size_t | |
808 | operator()(const Symbol_table_key&) const; | |
809 | }; | |
810 | ||
811 | struct Symbol_table_eq | |
812 | { | |
813 | bool | |
814 | operator()(const Symbol_table_key&, const Symbol_table_key&) const; | |
815 | }; | |
816 | ||
817 | typedef Unordered_map<Symbol_table_key, Symbol*, Symbol_table_hash, | |
818 | Symbol_table_eq> Symbol_table_type; | |
819 | ||
ead1e424 ILT |
820 | // The type of the list of common symbols. |
821 | ||
822 | typedef std::vector<Symbol*> Commons_type; | |
823 | ||
14bfc3f5 ILT |
824 | // The size of the symbols in the symbol table (32 or 64). |
825 | int size_; | |
826 | ||
ead1e424 ILT |
827 | // We increment this every time we see a new undefined symbol, for |
828 | // use in archive groups. | |
829 | int saw_undefined_; | |
830 | ||
75f65a3e ILT |
831 | // The file offset within the output symtab section where we should |
832 | // write the table. | |
833 | off_t offset_; | |
834 | ||
61ba1cf9 ILT |
835 | // The number of global symbols we want to write out. |
836 | size_t output_count_; | |
837 | ||
54dc6425 | 838 | // The symbol hash table. |
14bfc3f5 ILT |
839 | Symbol_table_type table_; |
840 | ||
54dc6425 ILT |
841 | // A pool of symbol names. This is used for all global symbols. |
842 | // Entries in the hash table point into this pool. | |
14bfc3f5 | 843 | Stringpool namepool_; |
bae7f79e | 844 | |
14bfc3f5 ILT |
845 | // Forwarding symbols. |
846 | Unordered_map<Symbol*, Symbol*> forwarders_; | |
ead1e424 ILT |
847 | |
848 | // We don't expect there to be very many common symbols, so we keep | |
849 | // a list of them. When we find a common symbol we add it to this | |
850 | // list. It is possible that by the time we process the list the | |
851 | // symbol is no longer a common symbol. It may also have become a | |
852 | // forwarder. | |
853 | Commons_type commons_; | |
f6ce93d6 ILT |
854 | |
855 | // Manage symbol warnings. | |
856 | Warnings warnings_; | |
bae7f79e ILT |
857 | }; |
858 | ||
1564db8d ILT |
859 | // We inline get_sized_symbol for efficiency. |
860 | ||
861 | template<int size> | |
862 | Sized_symbol<size>* | |
5482377d | 863 | Symbol_table::get_sized_symbol(Symbol* sym ACCEPT_SIZE) const |
1564db8d ILT |
864 | { |
865 | assert(size == this->get_size()); | |
866 | return static_cast<Sized_symbol<size>*>(sym); | |
867 | } | |
868 | ||
869 | template<int size> | |
870 | const Sized_symbol<size>* | |
5482377d | 871 | Symbol_table::get_sized_symbol(const Symbol* sym ACCEPT_SIZE) const |
1564db8d ILT |
872 | { |
873 | assert(size == this->get_size()); | |
874 | return static_cast<const Sized_symbol<size>*>(sym); | |
875 | } | |
876 | ||
bae7f79e ILT |
877 | } // End namespace gold. |
878 | ||
879 | #endif // !defined(GOLD_SYMTAB_H) |