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bae7f79e ILT |
1 | // symtab.h -- the gold symbol table -*- C++ -*- |
2 | ||
880cd20d | 3 | // Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc. |
6cb15b7f ILT |
4 | // Written by Ian Lance Taylor <iant@google.com>. |
5 | ||
6 | // This file is part of gold. | |
7 | ||
8 | // This program is free software; you can redistribute it and/or modify | |
9 | // it under the terms of the GNU General Public License as published by | |
10 | // the Free Software Foundation; either version 3 of the License, or | |
11 | // (at your option) any later version. | |
12 | ||
13 | // This program is distributed in the hope that it will be useful, | |
14 | // but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | // GNU General Public License for more details. | |
17 | ||
18 | // You should have received a copy of the GNU General Public License | |
19 | // along with this program; if not, write to the Free Software | |
20 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, | |
21 | // MA 02110-1301, USA. | |
22 | ||
bae7f79e ILT |
23 | // Symbol_table |
24 | // The symbol table. | |
25 | ||
f345227a ST |
26 | #ifndef GOLD_SYMTAB_H |
27 | #define GOLD_SYMTAB_H | |
28 | ||
bae7f79e ILT |
29 | #include <string> |
30 | #include <utility> | |
ead1e424 | 31 | #include <vector> |
bae7f79e ILT |
32 | |
33 | #include "elfcpp.h" | |
7e1edb90 | 34 | #include "parameters.h" |
14bfc3f5 | 35 | #include "stringpool.h" |
f6ce93d6 | 36 | #include "object.h" |
bae7f79e | 37 | |
bae7f79e ILT |
38 | namespace gold |
39 | { | |
40 | ||
7d9e3d98 | 41 | class Mapfile; |
14bfc3f5 | 42 | class Object; |
f6ce93d6 | 43 | class Relobj; |
dbe717ef ILT |
44 | template<int size, bool big_endian> |
45 | class Sized_relobj; | |
89fc3421 CC |
46 | template<int size, bool big_endian> |
47 | class Sized_pluginobj; | |
f6ce93d6 | 48 | class Dynobj; |
dbe717ef ILT |
49 | template<int size, bool big_endian> |
50 | class Sized_dynobj; | |
14b31740 | 51 | class Versions; |
09124467 | 52 | class Version_script_info; |
9a2d6984 | 53 | class Input_objects; |
ead1e424 | 54 | class Output_data; |
a3ad94ed | 55 | class Output_section; |
ead1e424 | 56 | class Output_segment; |
61ba1cf9 | 57 | class Output_file; |
d491d34e | 58 | class Output_symtab_xindex; |
6d03d481 | 59 | class Garbage_collection; |
ef15dade | 60 | class Icf; |
14bfc3f5 | 61 | |
14bfc3f5 ILT |
62 | // The base class of an entry in the symbol table. The symbol table |
63 | // can have a lot of entries, so we don't want this class to big. | |
64 | // Size dependent fields can be found in the template class | |
65 | // Sized_symbol. Targets may support their own derived classes. | |
bae7f79e | 66 | |
bae7f79e ILT |
67 | class Symbol |
68 | { | |
69 | public: | |
ead1e424 ILT |
70 | // Because we want the class to be small, we don't use any virtual |
71 | // functions. But because symbols can be defined in different | |
72 | // places, we need to classify them. This enum is the different | |
73 | // sources of symbols we support. | |
74 | enum Source | |
75 | { | |
f6ce93d6 ILT |
76 | // Symbol defined in a relocatable or dynamic input file--this is |
77 | // the most common case. | |
ead1e424 ILT |
78 | FROM_OBJECT, |
79 | // Symbol defined in an Output_data, a special section created by | |
80 | // the target. | |
81 | IN_OUTPUT_DATA, | |
82 | // Symbol defined in an Output_segment, with no associated | |
83 | // section. | |
84 | IN_OUTPUT_SEGMENT, | |
85 | // Symbol value is constant. | |
f3e9c5c5 ILT |
86 | IS_CONSTANT, |
87 | // Symbol is undefined. | |
88 | IS_UNDEFINED | |
ead1e424 ILT |
89 | }; |
90 | ||
91 | // When the source is IN_OUTPUT_SEGMENT, we need to describe what | |
92 | // the offset means. | |
93 | enum Segment_offset_base | |
94 | { | |
95 | // From the start of the segment. | |
96 | SEGMENT_START, | |
97 | // From the end of the segment. | |
98 | SEGMENT_END, | |
99 | // From the filesz of the segment--i.e., after the loaded bytes | |
100 | // but before the bytes which are allocated but zeroed. | |
101 | SEGMENT_BSS | |
102 | }; | |
103 | ||
14bfc3f5 ILT |
104 | // Return the symbol name. |
105 | const char* | |
106 | name() const | |
107 | { return this->name_; } | |
108 | ||
a2b1aa12 ILT |
109 | // Return the (ANSI) demangled version of the name, if |
110 | // parameters.demangle() is true. Otherwise, return the name. This | |
111 | // is intended to be used only for logging errors, so it's not | |
112 | // super-efficient. | |
113 | std::string | |
114 | demangled_name() const; | |
115 | ||
14bfc3f5 ILT |
116 | // Return the symbol version. This will return NULL for an |
117 | // unversioned symbol. | |
118 | const char* | |
119 | version() const | |
120 | { return this->version_; } | |
121 | ||
09124467 ILT |
122 | // Return whether this version is the default for this symbol name |
123 | // (eg, "foo@@V2" is a default version; "foo@V1" is not). Only | |
124 | // meaningful for versioned symbols. | |
125 | bool | |
126 | is_default() const | |
127 | { | |
128 | gold_assert(this->version_ != NULL); | |
129 | return this->is_def_; | |
130 | } | |
131 | ||
be3e6201 | 132 | // Set that this version is the default for this symbol name. |
09124467 | 133 | void |
be3e6201 ILT |
134 | set_is_default() |
135 | { this->is_def_ = true; } | |
09124467 | 136 | |
ead1e424 ILT |
137 | // Return the symbol source. |
138 | Source | |
139 | source() const | |
140 | { return this->source_; } | |
141 | ||
14bfc3f5 ILT |
142 | // Return the object with which this symbol is associated. |
143 | Object* | |
144 | object() const | |
ead1e424 | 145 | { |
a3ad94ed | 146 | gold_assert(this->source_ == FROM_OBJECT); |
ead1e424 ILT |
147 | return this->u_.from_object.object; |
148 | } | |
149 | ||
f6ce93d6 ILT |
150 | // Return the index of the section in the input relocatable or |
151 | // dynamic object file. | |
ead1e424 | 152 | unsigned int |
d491d34e | 153 | shndx(bool* is_ordinary) const |
ead1e424 | 154 | { |
a3ad94ed | 155 | gold_assert(this->source_ == FROM_OBJECT); |
d491d34e | 156 | *is_ordinary = this->is_ordinary_shndx_; |
16649710 | 157 | return this->u_.from_object.shndx; |
ead1e424 ILT |
158 | } |
159 | ||
160 | // Return the output data section with which this symbol is | |
161 | // associated, if the symbol was specially defined with respect to | |
162 | // an output data section. | |
163 | Output_data* | |
164 | output_data() const | |
165 | { | |
a3ad94ed | 166 | gold_assert(this->source_ == IN_OUTPUT_DATA); |
ead1e424 ILT |
167 | return this->u_.in_output_data.output_data; |
168 | } | |
169 | ||
170 | // If this symbol was defined with respect to an output data | |
171 | // section, return whether the value is an offset from end. | |
172 | bool | |
173 | offset_is_from_end() const | |
174 | { | |
a3ad94ed | 175 | gold_assert(this->source_ == IN_OUTPUT_DATA); |
ead1e424 ILT |
176 | return this->u_.in_output_data.offset_is_from_end; |
177 | } | |
178 | ||
179 | // Return the output segment with which this symbol is associated, | |
180 | // if the symbol was specially defined with respect to an output | |
181 | // segment. | |
182 | Output_segment* | |
183 | output_segment() const | |
184 | { | |
a3ad94ed | 185 | gold_assert(this->source_ == IN_OUTPUT_SEGMENT); |
ead1e424 ILT |
186 | return this->u_.in_output_segment.output_segment; |
187 | } | |
188 | ||
189 | // If this symbol was defined with respect to an output segment, | |
190 | // return the offset base. | |
191 | Segment_offset_base | |
192 | offset_base() const | |
193 | { | |
a3ad94ed | 194 | gold_assert(this->source_ == IN_OUTPUT_SEGMENT); |
ead1e424 ILT |
195 | return this->u_.in_output_segment.offset_base; |
196 | } | |
14bfc3f5 ILT |
197 | |
198 | // Return the symbol binding. | |
199 | elfcpp::STB | |
200 | binding() const | |
201 | { return this->binding_; } | |
202 | ||
1564db8d ILT |
203 | // Return the symbol type. |
204 | elfcpp::STT | |
205 | type() const | |
206 | { return this->type_; } | |
207 | ||
53d7974c L |
208 | // Return true for function symbol. |
209 | bool | |
210 | is_func() const | |
211 | { | |
212 | return (this->type_ == elfcpp::STT_FUNC | |
213 | || this->type_ == elfcpp::STT_GNU_IFUNC); | |
214 | } | |
215 | ||
1564db8d ILT |
216 | // Return the symbol visibility. |
217 | elfcpp::STV | |
218 | visibility() const | |
219 | { return this->visibility_; } | |
220 | ||
0602e05a ILT |
221 | // Set the visibility. |
222 | void | |
2ea97941 ILT |
223 | set_visibility(elfcpp::STV visibility) |
224 | { this->visibility_ = visibility; } | |
0602e05a ILT |
225 | |
226 | // Override symbol visibility. | |
227 | void | |
228 | override_visibility(elfcpp::STV); | |
229 | ||
ce279a62 CC |
230 | // Set whether the symbol was originally a weak undef or a regular undef |
231 | // when resolved by a dynamic def. | |
232 | inline void | |
233 | set_undef_binding(elfcpp::STB bind) | |
234 | { | |
235 | if (!this->undef_binding_set_ || this->undef_binding_weak_) | |
236 | { | |
237 | this->undef_binding_weak_ = bind == elfcpp::STB_WEAK; | |
238 | this->undef_binding_set_ = true; | |
239 | } | |
240 | } | |
241 | ||
242 | // Return TRUE if a weak undef was resolved by a dynamic def. | |
243 | inline bool | |
244 | is_undef_binding_weak() const | |
245 | { return this->undef_binding_weak_; } | |
246 | ||
1564db8d ILT |
247 | // Return the non-visibility part of the st_other field. |
248 | unsigned char | |
ead1e424 ILT |
249 | nonvis() const |
250 | { return this->nonvis_; } | |
14bfc3f5 | 251 | |
1564db8d ILT |
252 | // Return whether this symbol is a forwarder. This will never be |
253 | // true of a symbol found in the hash table, but may be true of | |
254 | // symbol pointers attached to object files. | |
255 | bool | |
256 | is_forwarder() const | |
257 | { return this->is_forwarder_; } | |
258 | ||
259 | // Mark this symbol as a forwarder. | |
260 | void | |
261 | set_forwarder() | |
262 | { this->is_forwarder_ = true; } | |
263 | ||
aeddab66 ILT |
264 | // Return whether this symbol has an alias in the weak aliases table |
265 | // in Symbol_table. | |
266 | bool | |
267 | has_alias() const | |
268 | { return this->has_alias_; } | |
269 | ||
270 | // Mark this symbol as having an alias. | |
271 | void | |
272 | set_has_alias() | |
273 | { this->has_alias_ = true; } | |
274 | ||
c06b7b0b ILT |
275 | // Return whether this symbol needs an entry in the dynamic symbol |
276 | // table. | |
277 | bool | |
278 | needs_dynsym_entry() const | |
429c1569 ILT |
279 | { |
280 | return (this->needs_dynsym_entry_ | |
8d6d383d ILT |
281 | || (this->in_reg() |
282 | && this->in_dyn() | |
283 | && this->is_externally_visible())); | |
429c1569 | 284 | } |
c06b7b0b ILT |
285 | |
286 | // Mark this symbol as needing an entry in the dynamic symbol table. | |
287 | void | |
288 | set_needs_dynsym_entry() | |
289 | { this->needs_dynsym_entry_ = true; } | |
290 | ||
436ca963 ILT |
291 | // Return whether this symbol should be added to the dynamic symbol |
292 | // table. | |
293 | bool | |
ce97fa81 | 294 | should_add_dynsym_entry(Symbol_table*) const; |
436ca963 | 295 | |
008db82e ILT |
296 | // Return whether this symbol has been seen in a regular object. |
297 | bool | |
298 | in_reg() const | |
299 | { return this->in_reg_; } | |
300 | ||
301 | // Mark this symbol as having been seen in a regular object. | |
302 | void | |
303 | set_in_reg() | |
304 | { this->in_reg_ = true; } | |
305 | ||
1ebd95fd ILT |
306 | // Return whether this symbol has been seen in a dynamic object. |
307 | bool | |
308 | in_dyn() const | |
309 | { return this->in_dyn_; } | |
310 | ||
f6ce93d6 | 311 | // Mark this symbol as having been seen in a dynamic object. |
1564db8d ILT |
312 | void |
313 | set_in_dyn() | |
314 | { this->in_dyn_ = true; } | |
315 | ||
89fc3421 CC |
316 | // Return whether this symbol has been seen in a real ELF object. |
317 | // (IN_REG will return TRUE if the symbol has been seen in either | |
318 | // a real ELF object or an object claimed by a plugin.) | |
319 | bool | |
320 | in_real_elf() const | |
321 | { return this->in_real_elf_; } | |
322 | ||
323 | // Mark this symbol as having been seen in a real ELF object. | |
324 | void | |
325 | set_in_real_elf() | |
326 | { this->in_real_elf_ = true; } | |
327 | ||
880cd20d ILT |
328 | // Return whether this symbol was defined in a section that was |
329 | // discarded from the link. This is used to control some error | |
330 | // reporting. | |
331 | bool | |
332 | is_defined_in_discarded_section() const | |
333 | { return this->is_defined_in_discarded_section_; } | |
334 | ||
335 | // Mark this symbol as having been defined in a discarded section. | |
336 | void | |
337 | set_is_defined_in_discarded_section() | |
338 | { this->is_defined_in_discarded_section_ = true; } | |
339 | ||
c06b7b0b ILT |
340 | // Return the index of this symbol in the output file symbol table. |
341 | // A value of -1U means that this symbol is not going into the | |
342 | // output file. This starts out as zero, and is set to a non-zero | |
343 | // value by Symbol_table::finalize. It is an error to ask for the | |
344 | // symbol table index before it has been set. | |
345 | unsigned int | |
346 | symtab_index() const | |
347 | { | |
a3ad94ed | 348 | gold_assert(this->symtab_index_ != 0); |
c06b7b0b ILT |
349 | return this->symtab_index_; |
350 | } | |
351 | ||
352 | // Set the index of the symbol in the output file symbol table. | |
353 | void | |
354 | set_symtab_index(unsigned int index) | |
355 | { | |
a3ad94ed | 356 | gold_assert(index != 0); |
c06b7b0b ILT |
357 | this->symtab_index_ = index; |
358 | } | |
359 | ||
a3ad94ed ILT |
360 | // Return whether this symbol already has an index in the output |
361 | // file symbol table. | |
362 | bool | |
363 | has_symtab_index() const | |
364 | { return this->symtab_index_ != 0; } | |
365 | ||
c06b7b0b ILT |
366 | // Return the index of this symbol in the dynamic symbol table. A |
367 | // value of -1U means that this symbol is not going into the dynamic | |
368 | // symbol table. This starts out as zero, and is set to a non-zero | |
369 | // during Layout::finalize. It is an error to ask for the dynamic | |
370 | // symbol table index before it has been set. | |
371 | unsigned int | |
372 | dynsym_index() const | |
373 | { | |
a3ad94ed | 374 | gold_assert(this->dynsym_index_ != 0); |
c06b7b0b ILT |
375 | return this->dynsym_index_; |
376 | } | |
377 | ||
378 | // Set the index of the symbol in the dynamic symbol table. | |
379 | void | |
380 | set_dynsym_index(unsigned int index) | |
381 | { | |
a3ad94ed | 382 | gold_assert(index != 0); |
c06b7b0b ILT |
383 | this->dynsym_index_ = index; |
384 | } | |
385 | ||
16649710 ILT |
386 | // Return whether this symbol already has an index in the dynamic |
387 | // symbol table. | |
388 | bool | |
389 | has_dynsym_index() const | |
390 | { return this->dynsym_index_ != 0; } | |
391 | ||
ead1e424 | 392 | // Return whether this symbol has an entry in the GOT section. |
07f397ab | 393 | // For a TLS symbol, this GOT entry will hold its tp-relative offset. |
92e059d8 | 394 | bool |
0a65a3a7 CC |
395 | has_got_offset(unsigned int got_type) const |
396 | { return this->got_offsets_.get_offset(got_type) != -1U; } | |
ead1e424 ILT |
397 | |
398 | // Return the offset into the GOT section of this symbol. | |
399 | unsigned int | |
0a65a3a7 | 400 | got_offset(unsigned int got_type) const |
ead1e424 | 401 | { |
2ea97941 ILT |
402 | unsigned int got_offset = this->got_offsets_.get_offset(got_type); |
403 | gold_assert(got_offset != -1U); | |
404 | return got_offset; | |
ead1e424 ILT |
405 | } |
406 | ||
407 | // Set the GOT offset of this symbol. | |
408 | void | |
2ea97941 ILT |
409 | set_got_offset(unsigned int got_type, unsigned int got_offset) |
410 | { this->got_offsets_.set_offset(got_type, got_offset); } | |
07f397ab | 411 | |
0e70b911 CC |
412 | // Return the GOT offset list. |
413 | const Got_offset_list* | |
414 | got_offset_list() const | |
415 | { return this->got_offsets_.get_list(); } | |
416 | ||
a3ad94ed | 417 | // Return whether this symbol has an entry in the PLT section. |
ead1e424 | 418 | bool |
a3ad94ed | 419 | has_plt_offset() const |
880cd20d | 420 | { return this->plt_offset_ != -1U; } |
a3ad94ed ILT |
421 | |
422 | // Return the offset into the PLT section of this symbol. | |
423 | unsigned int | |
424 | plt_offset() const | |
425 | { | |
426 | gold_assert(this->has_plt_offset()); | |
427 | return this->plt_offset_; | |
428 | } | |
429 | ||
430 | // Set the PLT offset of this symbol. | |
431 | void | |
2ea97941 | 432 | set_plt_offset(unsigned int plt_offset) |
a3ad94ed | 433 | { |
880cd20d | 434 | gold_assert(plt_offset != -1U); |
2ea97941 | 435 | this->plt_offset_ = plt_offset; |
a3ad94ed ILT |
436 | } |
437 | ||
ab5c9e90 ILT |
438 | // Return whether this dynamic symbol needs a special value in the |
439 | // dynamic symbol table. | |
440 | bool | |
441 | needs_dynsym_value() const | |
442 | { return this->needs_dynsym_value_; } | |
443 | ||
444 | // Set that this dynamic symbol needs a special value in the dynamic | |
445 | // symbol table. | |
446 | void | |
447 | set_needs_dynsym_value() | |
448 | { | |
449 | gold_assert(this->object()->is_dynamic()); | |
450 | this->needs_dynsym_value_ = true; | |
451 | } | |
452 | ||
a3ad94ed ILT |
453 | // Return true if the final value of this symbol is known at link |
454 | // time. | |
455 | bool | |
b3b74ddc | 456 | final_value_is_known() const; |
ead1e424 | 457 | |
8a5e3e08 ILT |
458 | // Return true if SHNDX represents a common symbol. This depends on |
459 | // the target. | |
460 | static bool | |
461 | is_common_shndx(unsigned int shndx); | |
462 | ||
f6ce93d6 ILT |
463 | // Return whether this is a defined symbol (not undefined or |
464 | // common). | |
465 | bool | |
466 | is_defined() const | |
467 | { | |
d491d34e ILT |
468 | bool is_ordinary; |
469 | if (this->source_ != FROM_OBJECT) | |
f3e9c5c5 | 470 | return this->source_ != IS_UNDEFINED; |
2ea97941 | 471 | unsigned int shndx = this->shndx(&is_ordinary); |
d491d34e | 472 | return (is_ordinary |
2ea97941 ILT |
473 | ? shndx != elfcpp::SHN_UNDEF |
474 | : !Symbol::is_common_shndx(shndx)); | |
a3ad94ed ILT |
475 | } |
476 | ||
14b31740 | 477 | // Return true if this symbol is from a dynamic object. |
a3ad94ed | 478 | bool |
14b31740 | 479 | is_from_dynobj() const |
a3ad94ed | 480 | { |
14b31740 | 481 | return this->source_ == FROM_OBJECT && this->object()->is_dynamic(); |
f6ce93d6 ILT |
482 | } |
483 | ||
f3a2388f CC |
484 | // Return whether this is a placeholder symbol from a plugin object. |
485 | bool | |
486 | is_placeholder() const | |
487 | { | |
488 | return this->source_ == FROM_OBJECT && this->object()->pluginobj() != NULL; | |
489 | } | |
490 | ||
ead1e424 ILT |
491 | // Return whether this is an undefined symbol. |
492 | bool | |
493 | is_undefined() const | |
494 | { | |
d491d34e | 495 | bool is_ordinary; |
f3e9c5c5 ILT |
496 | return ((this->source_ == FROM_OBJECT |
497 | && this->shndx(&is_ordinary) == elfcpp::SHN_UNDEF | |
498 | && is_ordinary) | |
499 | || this->source_ == IS_UNDEFINED); | |
ead1e424 ILT |
500 | } |
501 | ||
86925eef CC |
502 | // Return whether this is a weak undefined symbol. |
503 | bool | |
504 | is_weak_undefined() const | |
f3e9c5c5 | 505 | { return this->is_undefined() && this->binding() == elfcpp::STB_WEAK; } |
86925eef | 506 | |
86925eef CC |
507 | // Return whether this is an absolute symbol. |
508 | bool | |
509 | is_absolute() const | |
510 | { | |
d491d34e | 511 | bool is_ordinary; |
f3e9c5c5 ILT |
512 | return ((this->source_ == FROM_OBJECT |
513 | && this->shndx(&is_ordinary) == elfcpp::SHN_ABS | |
514 | && !is_ordinary) | |
515 | || this->source_ == IS_CONSTANT); | |
86925eef CC |
516 | } |
517 | ||
ead1e424 ILT |
518 | // Return whether this is a common symbol. |
519 | bool | |
520 | is_common() const | |
521 | { | |
8a5e3e08 ILT |
522 | if (this->source_ != FROM_OBJECT) |
523 | return false; | |
eda294df ILT |
524 | if (this->type_ == elfcpp::STT_COMMON) |
525 | return true; | |
d491d34e | 526 | bool is_ordinary; |
2ea97941 ILT |
527 | unsigned int shndx = this->shndx(&is_ordinary); |
528 | return !is_ordinary && Symbol::is_common_shndx(shndx); | |
ead1e424 | 529 | } |
92e059d8 | 530 | |
a6badf5a ILT |
531 | // Return whether this symbol can be seen outside this object. |
532 | bool | |
533 | is_externally_visible() const | |
534 | { | |
535 | return (this->visibility_ == elfcpp::STV_DEFAULT | |
536 | || this->visibility_ == elfcpp::STV_PROTECTED); | |
537 | } | |
538 | ||
436ca963 ILT |
539 | // Return true if this symbol can be preempted by a definition in |
540 | // another link unit. | |
541 | bool | |
542 | is_preemptible() const | |
543 | { | |
386c048c ILT |
544 | // It doesn't make sense to ask whether a symbol defined in |
545 | // another object is preemptible. | |
546 | gold_assert(!this->is_from_dynobj()); | |
547 | ||
8fc19601 ILT |
548 | // It doesn't make sense to ask whether an undefined symbol |
549 | // is preemptible. | |
550 | gold_assert(!this->is_undefined()); | |
551 | ||
f1f70eae ILT |
552 | // If a symbol does not have default visibility, it can not be |
553 | // seen outside this link unit and therefore is not preemptible. | |
554 | if (this->visibility_ != elfcpp::STV_DEFAULT) | |
555 | return false; | |
556 | ||
557 | // If this symbol has been forced to be a local symbol by a | |
558 | // version script, then it is not visible outside this link unit | |
559 | // and is not preemptible. | |
560 | if (this->is_forced_local_) | |
561 | return false; | |
562 | ||
563 | // If we are not producing a shared library, then nothing is | |
564 | // preemptible. | |
565 | if (!parameters->options().shared()) | |
566 | return false; | |
567 | ||
568 | // If the user used -Bsymbolic, then nothing is preemptible. | |
569 | if (parameters->options().Bsymbolic()) | |
570 | return false; | |
571 | ||
572 | // If the user used -Bsymbolic-functions, then functions are not | |
573 | // preemptible. We explicitly check for not being STT_OBJECT, | |
574 | // rather than for being STT_FUNC, because that is what the GNU | |
575 | // linker does. | |
576 | if (this->type() != elfcpp::STT_OBJECT | |
577 | && parameters->options().Bsymbolic_functions()) | |
578 | return false; | |
579 | ||
580 | // Otherwise the symbol is preemptible. | |
581 | return true; | |
436ca963 ILT |
582 | } |
583 | ||
d61c6bd4 ILT |
584 | // Return true if this symbol is a function that needs a PLT entry. |
585 | // If the symbol is defined in a dynamic object or if it is subject | |
8fc19601 | 586 | // to pre-emption, we need to make a PLT entry. If we're doing a |
374ad285 | 587 | // static link or a -pie link, we don't create PLT entries. |
d61c6bd4 ILT |
588 | bool |
589 | needs_plt_entry() const | |
590 | { | |
6d479619 CC |
591 | // An undefined symbol from an executable does not need a PLT entry. |
592 | if (this->is_undefined() && !parameters->options().shared()) | |
593 | return false; | |
594 | ||
8fc19601 | 595 | return (!parameters->doing_static_link() |
374ad285 | 596 | && !parameters->options().pie() |
53d7974c | 597 | && this->is_func() |
8fc19601 | 598 | && (this->is_from_dynobj() |
f3c69fca | 599 | || this->is_undefined() |
8fc19601 | 600 | || this->is_preemptible())); |
d61c6bd4 ILT |
601 | } |
602 | ||
0700cf32 ILT |
603 | // When determining whether a reference to a symbol needs a dynamic |
604 | // relocation, we need to know several things about the reference. | |
605 | // These flags may be or'ed together. | |
606 | enum Reference_flags | |
607 | { | |
608 | // Reference to the symbol's absolute address. | |
609 | ABSOLUTE_REF = 1, | |
610 | // A non-PIC reference. | |
611 | NON_PIC_REF = 2, | |
612 | // A function call. | |
613 | FUNCTION_CALL = 4 | |
614 | }; | |
615 | ||
d61c6bd4 ILT |
616 | // Given a direct absolute or pc-relative static relocation against |
617 | // the global symbol, this function returns whether a dynamic relocation | |
618 | // is needed. | |
619 | ||
620 | bool | |
0700cf32 | 621 | needs_dynamic_reloc(int flags) const |
d61c6bd4 | 622 | { |
8fc19601 ILT |
623 | // No dynamic relocations in a static link! |
624 | if (parameters->doing_static_link()) | |
625 | return false; | |
626 | ||
6d479619 | 627 | // A reference to an undefined symbol from an executable should be |
f3c69fca CC |
628 | // statically resolved to 0, and does not need a dynamic relocation. |
629 | // This matches gnu ld behavior. | |
6d479619 | 630 | if (this->is_undefined() && !parameters->options().shared()) |
f3c69fca CC |
631 | return false; |
632 | ||
633 | // A reference to an absolute symbol does not need a dynamic relocation. | |
634 | if (this->is_absolute()) | |
86925eef CC |
635 | return false; |
636 | ||
d61c6bd4 | 637 | // An absolute reference within a position-independent output file |
0700cf32 ILT |
638 | // will need a dynamic relocation. |
639 | if ((flags & ABSOLUTE_REF) | |
8851ecca | 640 | && parameters->options().output_is_position_independent()) |
d61c6bd4 ILT |
641 | return true; |
642 | ||
643 | // A function call that can branch to a local PLT entry does not need | |
5240d12a ILT |
644 | // a dynamic relocation. A non-pic pc-relative function call in a |
645 | // shared library cannot use a PLT entry. | |
0700cf32 | 646 | if ((flags & FUNCTION_CALL) |
5240d12a | 647 | && this->has_plt_offset() |
8851ecca | 648 | && !((flags & NON_PIC_REF) && parameters->options().shared())) |
d61c6bd4 ILT |
649 | return false; |
650 | ||
651 | // A reference to any PLT entry in a non-position-independent executable | |
652 | // does not need a dynamic relocation. | |
8851ecca | 653 | if (!parameters->options().output_is_position_independent() |
d61c6bd4 ILT |
654 | && this->has_plt_offset()) |
655 | return false; | |
656 | ||
657 | // A reference to a symbol defined in a dynamic object or to a | |
658 | // symbol that is preemptible will need a dynamic relocation. | |
8fc19601 ILT |
659 | if (this->is_from_dynobj() |
660 | || this->is_undefined() | |
661 | || this->is_preemptible()) | |
d61c6bd4 ILT |
662 | return true; |
663 | ||
664 | // For all other cases, return FALSE. | |
665 | return false; | |
666 | } | |
667 | ||
de4c45bd ILT |
668 | // Whether we should use the PLT offset associated with a symbol for |
669 | // a relocation. IS_NON_PIC_REFERENCE is true if this is a non-PIC | |
670 | // reloc--the same set of relocs for which we would pass NON_PIC_REF | |
671 | // to the needs_dynamic_reloc function. | |
672 | ||
673 | bool | |
674 | use_plt_offset(bool is_non_pic_reference) const | |
675 | { | |
676 | // If the symbol doesn't have a PLT offset, then naturally we | |
677 | // don't want to use it. | |
678 | if (!this->has_plt_offset()) | |
679 | return false; | |
680 | ||
681 | // If we are going to generate a dynamic relocation, then we will | |
682 | // wind up using that, so no need to use the PLT entry. | |
683 | if (this->needs_dynamic_reloc(FUNCTION_CALL | |
684 | | (is_non_pic_reference | |
685 | ? NON_PIC_REF | |
686 | : 0))) | |
687 | return false; | |
688 | ||
689 | // If the symbol is from a dynamic object, we need to use the PLT | |
690 | // entry. | |
691 | if (this->is_from_dynobj()) | |
692 | return true; | |
693 | ||
694 | // If we are generating a shared object, and this symbol is | |
695 | // undefined or preemptible, we need to use the PLT entry. | |
696 | if (parameters->options().shared() | |
697 | && (this->is_undefined() || this->is_preemptible())) | |
698 | return true; | |
699 | ||
700 | // If this is a weak undefined symbol, we need to use the PLT | |
701 | // entry; the symbol may be defined by a library loaded at | |
702 | // runtime. | |
703 | if (this->is_weak_undefined()) | |
704 | return true; | |
705 | ||
706 | // Otherwise we can use the regular definition. | |
707 | return false; | |
708 | } | |
709 | ||
d61c6bd4 ILT |
710 | // Given a direct absolute static relocation against |
711 | // the global symbol, where a dynamic relocation is needed, this | |
712 | // function returns whether a relative dynamic relocation can be used. | |
713 | // The caller must determine separately whether the static relocation | |
714 | // is compatible with a relative relocation. | |
715 | ||
716 | bool | |
717 | can_use_relative_reloc(bool is_function_call) const | |
718 | { | |
719 | // A function call that can branch to a local PLT entry can | |
720 | // use a RELATIVE relocation. | |
721 | if (is_function_call && this->has_plt_offset()) | |
722 | return true; | |
723 | ||
724 | // A reference to a symbol defined in a dynamic object or to a | |
725 | // symbol that is preemptible can not use a RELATIVE relocaiton. | |
8fc19601 ILT |
726 | if (this->is_from_dynobj() |
727 | || this->is_undefined() | |
728 | || this->is_preemptible()) | |
d61c6bd4 ILT |
729 | return false; |
730 | ||
731 | // For all other cases, return TRUE. | |
732 | return true; | |
733 | } | |
734 | ||
77e65537 ILT |
735 | // Return the output section where this symbol is defined. Return |
736 | // NULL if the symbol has an absolute value. | |
737 | Output_section* | |
738 | output_section() const; | |
739 | ||
740 | // Set the symbol's output section. This is used for symbols | |
741 | // defined in scripts. This should only be called after the symbol | |
742 | // table has been finalized. | |
743 | void | |
744 | set_output_section(Output_section*); | |
a445fddf | 745 | |
f6ce93d6 ILT |
746 | // Return whether there should be a warning for references to this |
747 | // symbol. | |
748 | bool | |
749 | has_warning() const | |
750 | { return this->has_warning_; } | |
751 | ||
752 | // Mark this symbol as having a warning. | |
753 | void | |
754 | set_has_warning() | |
755 | { this->has_warning_ = true; } | |
756 | ||
46fe1623 ILT |
757 | // Return whether this symbol is defined by a COPY reloc from a |
758 | // dynamic object. | |
759 | bool | |
760 | is_copied_from_dynobj() const | |
761 | { return this->is_copied_from_dynobj_; } | |
762 | ||
763 | // Mark this symbol as defined by a COPY reloc. | |
764 | void | |
765 | set_is_copied_from_dynobj() | |
766 | { this->is_copied_from_dynobj_ = true; } | |
767 | ||
55a93433 ILT |
768 | // Return whether this symbol is forced to visibility STB_LOCAL |
769 | // by a "local:" entry in a version script. | |
770 | bool | |
771 | is_forced_local() const | |
772 | { return this->is_forced_local_; } | |
773 | ||
774 | // Mark this symbol as forced to STB_LOCAL visibility. | |
775 | void | |
776 | set_is_forced_local() | |
777 | { this->is_forced_local_ = true; } | |
778 | ||
966d4097 DK |
779 | // Return true if this may need a COPY relocation. |
780 | // References from an executable object to non-function symbols | |
781 | // defined in a dynamic object may need a COPY relocation. | |
782 | bool | |
783 | may_need_copy_reloc() const | |
784 | { | |
785 | return (!parameters->options().shared() | |
786 | && parameters->options().copyreloc() | |
787 | && this->is_from_dynobj() | |
53d7974c | 788 | && !this->is_func()); |
966d4097 DK |
789 | } |
790 | ||
14bfc3f5 ILT |
791 | protected: |
792 | // Instances of this class should always be created at a specific | |
793 | // size. | |
794 | Symbol() | |
f6ce93d6 | 795 | { memset(this, 0, sizeof *this); } |
14bfc3f5 | 796 | |
ead1e424 ILT |
797 | // Initialize the general fields. |
798 | void | |
799 | init_fields(const char* name, const char* version, | |
800 | elfcpp::STT type, elfcpp::STB binding, | |
801 | elfcpp::STV visibility, unsigned char nonvis); | |
802 | ||
d491d34e ILT |
803 | // Initialize fields from an ELF symbol in OBJECT. ST_SHNDX is the |
804 | // section index, IS_ORDINARY is whether it is a normal section | |
805 | // index rather than a special code. | |
14bfc3f5 ILT |
806 | template<int size, bool big_endian> |
807 | void | |
f3e9c5c5 ILT |
808 | init_base_object(const char *name, const char* version, Object* object, |
809 | const elfcpp::Sym<size, big_endian>&, unsigned int st_shndx, | |
810 | bool is_ordinary); | |
bae7f79e | 811 | |
ead1e424 ILT |
812 | // Initialize fields for an Output_data. |
813 | void | |
75517b77 ILT |
814 | init_base_output_data(const char* name, const char* version, Output_data*, |
815 | elfcpp::STT, elfcpp::STB, elfcpp::STV, | |
816 | unsigned char nonvis, bool offset_is_from_end); | |
ead1e424 ILT |
817 | |
818 | // Initialize fields for an Output_segment. | |
819 | void | |
75517b77 ILT |
820 | init_base_output_segment(const char* name, const char* version, |
821 | Output_segment* os, elfcpp::STT type, | |
822 | elfcpp::STB binding, elfcpp::STV visibility, | |
823 | unsigned char nonvis, | |
f3e9c5c5 | 824 | Segment_offset_base offset_base); |
ead1e424 ILT |
825 | |
826 | // Initialize fields for a constant. | |
827 | void | |
75517b77 ILT |
828 | init_base_constant(const char* name, const char* version, elfcpp::STT type, |
829 | elfcpp::STB binding, elfcpp::STV visibility, | |
830 | unsigned char nonvis); | |
f3e9c5c5 ILT |
831 | |
832 | // Initialize fields for an undefined symbol. | |
833 | void | |
75517b77 ILT |
834 | init_base_undefined(const char* name, const char* version, elfcpp::STT type, |
835 | elfcpp::STB binding, elfcpp::STV visibility, | |
836 | unsigned char nonvis); | |
ead1e424 | 837 | |
1564db8d ILT |
838 | // Override existing symbol. |
839 | template<int size, bool big_endian> | |
840 | void | |
d491d34e ILT |
841 | override_base(const elfcpp::Sym<size, big_endian>&, unsigned int st_shndx, |
842 | bool is_ordinary, Object* object, const char* version); | |
1564db8d | 843 | |
86f2e683 ILT |
844 | // Override existing symbol with a special symbol. |
845 | void | |
846 | override_base_with_special(const Symbol* from); | |
847 | ||
75517b77 ILT |
848 | // Override symbol version. |
849 | void | |
850 | override_version(const char* version); | |
851 | ||
c7912668 ILT |
852 | // Allocate a common symbol by giving it a location in the output |
853 | // file. | |
854 | void | |
855 | allocate_base_common(Output_data*); | |
856 | ||
bae7f79e | 857 | private: |
14bfc3f5 ILT |
858 | Symbol(const Symbol&); |
859 | Symbol& operator=(const Symbol&); | |
860 | ||
861 | // Symbol name (expected to point into a Stringpool). | |
862 | const char* name_; | |
863 | // Symbol version (expected to point into a Stringpool). This may | |
864 | // be NULL. | |
bae7f79e | 865 | const char* version_; |
ead1e424 ILT |
866 | |
867 | union | |
868 | { | |
869 | // This struct is used if SOURCE_ == FROM_OBJECT. | |
870 | struct | |
871 | { | |
872 | // Object in which symbol is defined, or in which it was first | |
873 | // seen. | |
874 | Object* object; | |
875 | // Section number in object_ in which symbol is defined. | |
16649710 | 876 | unsigned int shndx; |
ead1e424 ILT |
877 | } from_object; |
878 | ||
879 | // This struct is used if SOURCE_ == IN_OUTPUT_DATA. | |
880 | struct | |
881 | { | |
882 | // Output_data in which symbol is defined. Before | |
883 | // Layout::finalize the symbol's value is an offset within the | |
884 | // Output_data. | |
885 | Output_data* output_data; | |
886 | // True if the offset is from the end, false if the offset is | |
887 | // from the beginning. | |
888 | bool offset_is_from_end; | |
889 | } in_output_data; | |
890 | ||
891 | // This struct is used if SOURCE_ == IN_OUTPUT_SEGMENT. | |
892 | struct | |
893 | { | |
894 | // Output_segment in which the symbol is defined. Before | |
895 | // Layout::finalize the symbol's value is an offset. | |
896 | Output_segment* output_segment; | |
897 | // The base to use for the offset before Layout::finalize. | |
898 | Segment_offset_base offset_base; | |
899 | } in_output_segment; | |
900 | } u_; | |
901 | ||
c06b7b0b ILT |
902 | // The index of this symbol in the output file. If the symbol is |
903 | // not going into the output file, this value is -1U. This field | |
904 | // starts as always holding zero. It is set to a non-zero value by | |
905 | // Symbol_table::finalize. | |
906 | unsigned int symtab_index_; | |
907 | ||
908 | // The index of this symbol in the dynamic symbol table. If the | |
909 | // symbol is not going into the dynamic symbol table, this value is | |
910 | // -1U. This field starts as always holding zero. It is set to a | |
911 | // non-zero value during Layout::finalize. | |
912 | unsigned int dynsym_index_; | |
913 | ||
880cd20d ILT |
914 | // The GOT section entries for this symbol. A symbol may have more |
915 | // than one GOT offset (e.g., when mixing modules compiled with two | |
916 | // different TLS models), but will usually have at most one. | |
0a65a3a7 | 917 | Got_offset_list got_offsets_; |
07f397ab | 918 | |
880cd20d ILT |
919 | // If this symbol has an entry in the PLT section, then this is the |
920 | // offset from the start of the PLT section. This is -1U if there | |
921 | // is no PLT entry. | |
a3ad94ed ILT |
922 | unsigned int plt_offset_; |
923 | ||
d491d34e | 924 | // Symbol type (bits 0 to 3). |
bae7f79e | 925 | elfcpp::STT type_ : 4; |
d491d34e | 926 | // Symbol binding (bits 4 to 7). |
bae7f79e | 927 | elfcpp::STB binding_ : 4; |
d491d34e | 928 | // Symbol visibility (bits 8 to 9). |
14bfc3f5 | 929 | elfcpp::STV visibility_ : 2; |
d491d34e | 930 | // Rest of symbol st_other field (bits 10 to 15). |
ead1e424 | 931 | unsigned int nonvis_ : 6; |
d491d34e | 932 | // The type of symbol (bits 16 to 18). |
f6ce93d6 | 933 | Source source_ : 3; |
880cd20d | 934 | // True if this is the default version of the symbol (bit 19). |
1564db8d | 935 | bool is_def_ : 1; |
14bfc3f5 ILT |
936 | // True if this symbol really forwards to another symbol. This is |
937 | // used when we discover after the fact that two different entries | |
938 | // in the hash table really refer to the same symbol. This will | |
939 | // never be set for a symbol found in the hash table, but may be set | |
940 | // for a symbol found in the list of symbols attached to an Object. | |
941 | // It forwards to the symbol found in the forwarders_ map of | |
880cd20d | 942 | // Symbol_table (bit 20). |
1564db8d | 943 | bool is_forwarder_ : 1; |
aeddab66 | 944 | // True if the symbol has an alias in the weak_aliases table in |
880cd20d | 945 | // Symbol_table (bit 21). |
aeddab66 | 946 | bool has_alias_ : 1; |
d491d34e | 947 | // True if this symbol needs to be in the dynamic symbol table (bit |
880cd20d | 948 | // 22). |
c06b7b0b | 949 | bool needs_dynsym_entry_ : 1; |
880cd20d | 950 | // True if we've seen this symbol in a regular object (bit 23). |
008db82e | 951 | bool in_reg_ : 1; |
880cd20d | 952 | // True if we've seen this symbol in a dynamic object (bit 24). |
1564db8d | 953 | bool in_dyn_ : 1; |
ab5c9e90 | 954 | // True if this is a dynamic symbol which needs a special value in |
880cd20d | 955 | // the dynamic symbol table (bit 25). |
ab5c9e90 | 956 | bool needs_dynsym_value_ : 1; |
880cd20d | 957 | // True if there is a warning for this symbol (bit 26). |
f6ce93d6 | 958 | bool has_warning_ : 1; |
46fe1623 | 959 | // True if we are using a COPY reloc for this symbol, so that the |
880cd20d | 960 | // real definition lives in a dynamic object (bit 27). |
46fe1623 | 961 | bool is_copied_from_dynobj_ : 1; |
55a93433 | 962 | // True if this symbol was forced to local visibility by a version |
880cd20d | 963 | // script (bit 28). |
55a93433 | 964 | bool is_forced_local_ : 1; |
d491d34e ILT |
965 | // True if the field u_.from_object.shndx is an ordinary section |
966 | // index, not one of the special codes from SHN_LORESERVE to | |
880cd20d | 967 | // SHN_HIRESERVE (bit 29). |
d491d34e | 968 | bool is_ordinary_shndx_ : 1; |
880cd20d | 969 | // True if we've seen this symbol in a real ELF object (bit 30). |
89fc3421 | 970 | bool in_real_elf_ : 1; |
880cd20d ILT |
971 | // True if this symbol is defined in a section which was discarded |
972 | // (bit 31). | |
973 | bool is_defined_in_discarded_section_ : 1; | |
ce279a62 CC |
974 | // True if UNDEF_BINDING_WEAK_ has been set (bit 32). |
975 | bool undef_binding_set_ : 1; | |
976 | // True if this symbol was a weak undef resolved by a dynamic def | |
977 | // (bit 33). | |
978 | bool undef_binding_weak_ : 1; | |
bae7f79e ILT |
979 | }; |
980 | ||
14bfc3f5 ILT |
981 | // The parts of a symbol which are size specific. Using a template |
982 | // derived class like this helps us use less space on a 32-bit system. | |
bae7f79e ILT |
983 | |
984 | template<int size> | |
14bfc3f5 ILT |
985 | class Sized_symbol : public Symbol |
986 | { | |
987 | public: | |
1564db8d ILT |
988 | typedef typename elfcpp::Elf_types<size>::Elf_Addr Value_type; |
989 | typedef typename elfcpp::Elf_types<size>::Elf_WXword Size_type; | |
990 | ||
14bfc3f5 ILT |
991 | Sized_symbol() |
992 | { } | |
993 | ||
d491d34e ILT |
994 | // Initialize fields from an ELF symbol in OBJECT. ST_SHNDX is the |
995 | // section index, IS_ORDINARY is whether it is a normal section | |
996 | // index rather than a special code. | |
14bfc3f5 ILT |
997 | template<bool big_endian> |
998 | void | |
f3e9c5c5 ILT |
999 | init_object(const char *name, const char* version, Object* object, |
1000 | const elfcpp::Sym<size, big_endian>&, unsigned int st_shndx, | |
1001 | bool is_ordinary); | |
14bfc3f5 | 1002 | |
ead1e424 ILT |
1003 | // Initialize fields for an Output_data. |
1004 | void | |
75517b77 ILT |
1005 | init_output_data(const char* name, const char* version, Output_data*, |
1006 | Value_type value, Size_type symsize, elfcpp::STT, | |
1007 | elfcpp::STB, elfcpp::STV, unsigned char nonvis, | |
1008 | bool offset_is_from_end); | |
ead1e424 ILT |
1009 | |
1010 | // Initialize fields for an Output_segment. | |
1011 | void | |
75517b77 ILT |
1012 | init_output_segment(const char* name, const char* version, Output_segment*, |
1013 | Value_type value, Size_type symsize, elfcpp::STT, | |
1014 | elfcpp::STB, elfcpp::STV, unsigned char nonvis, | |
1015 | Segment_offset_base offset_base); | |
ead1e424 ILT |
1016 | |
1017 | // Initialize fields for a constant. | |
1018 | void | |
75517b77 ILT |
1019 | init_constant(const char* name, const char* version, Value_type value, |
1020 | Size_type symsize, elfcpp::STT, elfcpp::STB, elfcpp::STV, | |
1021 | unsigned char nonvis); | |
f3e9c5c5 ILT |
1022 | |
1023 | // Initialize fields for an undefined symbol. | |
1024 | void | |
75517b77 ILT |
1025 | init_undefined(const char* name, const char* version, elfcpp::STT, |
1026 | elfcpp::STB, elfcpp::STV, unsigned char nonvis); | |
ead1e424 | 1027 | |
1564db8d ILT |
1028 | // Override existing symbol. |
1029 | template<bool big_endian> | |
1030 | void | |
d491d34e ILT |
1031 | override(const elfcpp::Sym<size, big_endian>&, unsigned int st_shndx, |
1032 | bool is_ordinary, Object* object, const char* version); | |
1564db8d | 1033 | |
86f2e683 ILT |
1034 | // Override existing symbol with a special symbol. |
1035 | void | |
1036 | override_with_special(const Sized_symbol<size>*); | |
1037 | ||
1564db8d ILT |
1038 | // Return the symbol's value. |
1039 | Value_type | |
1040 | value() const | |
1041 | { return this->value_; } | |
1042 | ||
1043 | // Return the symbol's size (we can't call this 'size' because that | |
1044 | // is a template parameter). | |
1045 | Size_type | |
1046 | symsize() const | |
ead1e424 ILT |
1047 | { return this->symsize_; } |
1048 | ||
1049 | // Set the symbol size. This is used when resolving common symbols. | |
1050 | void | |
2ea97941 ILT |
1051 | set_symsize(Size_type symsize) |
1052 | { this->symsize_ = symsize; } | |
1564db8d | 1053 | |
75f65a3e ILT |
1054 | // Set the symbol value. This is called when we store the final |
1055 | // values of the symbols into the symbol table. | |
1056 | void | |
2ea97941 ILT |
1057 | set_value(Value_type value) |
1058 | { this->value_ = value; } | |
75f65a3e | 1059 | |
c7912668 ILT |
1060 | // Allocate a common symbol by giving it a location in the output |
1061 | // file. | |
1062 | void | |
1063 | allocate_common(Output_data*, Value_type value); | |
1064 | ||
14bfc3f5 ILT |
1065 | private: |
1066 | Sized_symbol(const Sized_symbol&); | |
1067 | Sized_symbol& operator=(const Sized_symbol&); | |
1068 | ||
ead1e424 ILT |
1069 | // Symbol value. Before Layout::finalize this is the offset in the |
1070 | // input section. This is set to the final value during | |
1071 | // Layout::finalize. | |
1564db8d | 1072 | Value_type value_; |
14bfc3f5 | 1073 | // Symbol size. |
ead1e424 ILT |
1074 | Size_type symsize_; |
1075 | }; | |
1076 | ||
1077 | // A struct describing a symbol defined by the linker, where the value | |
1078 | // of the symbol is defined based on an output section. This is used | |
1079 | // for symbols defined by the linker, like "_init_array_start". | |
1080 | ||
1081 | struct Define_symbol_in_section | |
1082 | { | |
1083 | // The symbol name. | |
1084 | const char* name; | |
1085 | // The name of the output section with which this symbol should be | |
1086 | // associated. If there is no output section with that name, the | |
1087 | // symbol will be defined as zero. | |
1088 | const char* output_section; | |
1089 | // The offset of the symbol within the output section. This is an | |
1090 | // offset from the start of the output section, unless start_at_end | |
1091 | // is true, in which case this is an offset from the end of the | |
1092 | // output section. | |
1093 | uint64_t value; | |
1094 | // The size of the symbol. | |
1095 | uint64_t size; | |
1096 | // The symbol type. | |
1097 | elfcpp::STT type; | |
1098 | // The symbol binding. | |
1099 | elfcpp::STB binding; | |
1100 | // The symbol visibility. | |
1101 | elfcpp::STV visibility; | |
1102 | // The rest of the st_other field. | |
1103 | unsigned char nonvis; | |
1104 | // If true, the value field is an offset from the end of the output | |
1105 | // section. | |
1106 | bool offset_is_from_end; | |
1107 | // If true, this symbol is defined only if we see a reference to it. | |
1108 | bool only_if_ref; | |
1109 | }; | |
1110 | ||
1111 | // A struct describing a symbol defined by the linker, where the value | |
1112 | // of the symbol is defined based on a segment. This is used for | |
1113 | // symbols defined by the linker, like "_end". We describe the | |
1114 | // segment with which the symbol should be associated by its | |
1115 | // characteristics. If no segment meets these characteristics, the | |
1116 | // symbol will be defined as zero. If there is more than one segment | |
1117 | // which meets these characteristics, we will use the first one. | |
1118 | ||
1119 | struct Define_symbol_in_segment | |
1120 | { | |
1121 | // The symbol name. | |
1122 | const char* name; | |
1123 | // The segment type where the symbol should be defined, typically | |
1124 | // PT_LOAD. | |
1125 | elfcpp::PT segment_type; | |
1126 | // Bitmask of segment flags which must be set. | |
1127 | elfcpp::PF segment_flags_set; | |
1128 | // Bitmask of segment flags which must be clear. | |
1129 | elfcpp::PF segment_flags_clear; | |
1130 | // The offset of the symbol within the segment. The offset is | |
1131 | // calculated from the position set by offset_base. | |
1132 | uint64_t value; | |
1133 | // The size of the symbol. | |
1134 | uint64_t size; | |
1135 | // The symbol type. | |
1136 | elfcpp::STT type; | |
1137 | // The symbol binding. | |
1138 | elfcpp::STB binding; | |
1139 | // The symbol visibility. | |
1140 | elfcpp::STV visibility; | |
1141 | // The rest of the st_other field. | |
1142 | unsigned char nonvis; | |
1143 | // The base from which we compute the offset. | |
1144 | Symbol::Segment_offset_base offset_base; | |
1145 | // If true, this symbol is defined only if we see a reference to it. | |
1146 | bool only_if_ref; | |
14bfc3f5 ILT |
1147 | }; |
1148 | ||
f6ce93d6 ILT |
1149 | // This class manages warnings. Warnings are a GNU extension. When |
1150 | // we see a section named .gnu.warning.SYM in an object file, and if | |
1151 | // we wind using the definition of SYM from that object file, then we | |
1152 | // will issue a warning for any relocation against SYM from a | |
1153 | // different object file. The text of the warning is the contents of | |
1154 | // the section. This is not precisely the definition used by the old | |
1155 | // GNU linker; the old GNU linker treated an occurrence of | |
1156 | // .gnu.warning.SYM as defining a warning symbol. A warning symbol | |
1157 | // would trigger a warning on any reference. However, it was | |
1158 | // inconsistent in that a warning in a dynamic object only triggered | |
1159 | // if there was no definition in a regular object. This linker is | |
1160 | // different in that we only issue a warning if we use the symbol | |
1161 | // definition from the same object file as the warning section. | |
1162 | ||
1163 | class Warnings | |
1164 | { | |
1165 | public: | |
1166 | Warnings() | |
1167 | : warnings_() | |
1168 | { } | |
1169 | ||
cb295612 ILT |
1170 | // Add a warning for symbol NAME in object OBJ. WARNING is the text |
1171 | // of the warning. | |
f6ce93d6 ILT |
1172 | void |
1173 | add_warning(Symbol_table* symtab, const char* name, Object* obj, | |
cb295612 | 1174 | const std::string& warning); |
f6ce93d6 ILT |
1175 | |
1176 | // For each symbol for which we should give a warning, make a note | |
1177 | // on the symbol. | |
1178 | void | |
cb295612 | 1179 | note_warnings(Symbol_table* symtab); |
f6ce93d6 | 1180 | |
75f2446e ILT |
1181 | // Issue a warning for a reference to SYM at RELINFO's location. |
1182 | template<int size, bool big_endian> | |
f6ce93d6 | 1183 | void |
75f2446e ILT |
1184 | issue_warning(const Symbol* sym, const Relocate_info<size, big_endian>*, |
1185 | size_t relnum, off_t reloffset) const; | |
f6ce93d6 ILT |
1186 | |
1187 | private: | |
1188 | Warnings(const Warnings&); | |
1189 | Warnings& operator=(const Warnings&); | |
1190 | ||
1191 | // What we need to know to get the warning text. | |
1192 | struct Warning_location | |
1193 | { | |
1194 | // The object the warning is in. | |
1195 | Object* object; | |
cb295612 | 1196 | // The warning text. |
f6ce93d6 ILT |
1197 | std::string text; |
1198 | ||
1199 | Warning_location() | |
cb295612 | 1200 | : object(NULL), text() |
f6ce93d6 ILT |
1201 | { } |
1202 | ||
1203 | void | |
cb295612 | 1204 | set(Object* o, const std::string& t) |
f6ce93d6 ILT |
1205 | { |
1206 | this->object = o; | |
cb295612 | 1207 | this->text = t; |
f6ce93d6 | 1208 | } |
f6ce93d6 ILT |
1209 | }; |
1210 | ||
1211 | // A mapping from warning symbol names (canonicalized in | |
70e654ba | 1212 | // Symbol_table's namepool_ field) to warning information. |
f6ce93d6 ILT |
1213 | typedef Unordered_map<const char*, Warning_location> Warning_table; |
1214 | ||
1215 | Warning_table warnings_; | |
1216 | }; | |
1217 | ||
14bfc3f5 ILT |
1218 | // The main linker symbol table. |
1219 | ||
bae7f79e ILT |
1220 | class Symbol_table |
1221 | { | |
1222 | public: | |
99fff23b ILT |
1223 | // The different places where a symbol definition can come from. |
1224 | enum Defined | |
1225 | { | |
1226 | // Defined in an object file--the normal case. | |
1227 | OBJECT, | |
1228 | // Defined for a COPY reloc. | |
1229 | COPY, | |
1230 | // Defined on the command line using --defsym. | |
1231 | DEFSYM, | |
1232 | // Defined (so to speak) on the command line using -u. | |
1233 | UNDEFINED, | |
1234 | // Defined in a linker script. | |
1235 | SCRIPT, | |
1236 | // Predefined by the linker. | |
1237 | PREDEFINED, | |
1238 | }; | |
1239 | ||
fc59c572 ILT |
1240 | // The order in which we sort common symbols. |
1241 | enum Sort_commons_order | |
1242 | { | |
1243 | SORT_COMMONS_BY_SIZE_DESCENDING, | |
1244 | SORT_COMMONS_BY_ALIGNMENT_DESCENDING, | |
1245 | SORT_COMMONS_BY_ALIGNMENT_ASCENDING | |
1246 | }; | |
1247 | ||
6d013333 ILT |
1248 | // COUNT is an estimate of how many symbosl will be inserted in the |
1249 | // symbol table. It's ok to put 0 if you don't know; a correct | |
1250 | // guess will just save some CPU by reducing hashtable resizes. | |
09124467 | 1251 | Symbol_table(unsigned int count, const Version_script_info& version_script); |
bae7f79e | 1252 | |
1564db8d | 1253 | ~Symbol_table(); |
bae7f79e | 1254 | |
ef15dade | 1255 | void |
2ea97941 ILT |
1256 | set_icf(Icf* icf) |
1257 | { this->icf_ = icf;} | |
ef15dade ST |
1258 | |
1259 | Icf* | |
1260 | icf() const | |
1261 | { return this->icf_; } | |
1262 | ||
1263 | // Returns true if ICF determined that this is a duplicate section. | |
1264 | bool | |
1265 | is_section_folded(Object* obj, unsigned int shndx) const; | |
1266 | ||
6d03d481 | 1267 | void |
2ea97941 ILT |
1268 | set_gc(Garbage_collection* gc) |
1269 | { this->gc_ = gc; } | |
6d03d481 ST |
1270 | |
1271 | Garbage_collection* | |
ef15dade | 1272 | gc() const |
6d03d481 ST |
1273 | { return this->gc_; } |
1274 | ||
1275 | // During garbage collection, this keeps undefined symbols. | |
1276 | void | |
88a4108b | 1277 | gc_mark_undef_symbols(Layout*); |
6d03d481 ST |
1278 | |
1279 | // During garbage collection, this ensures externally visible symbols | |
1280 | // are not treated as garbage while building shared objects. | |
1281 | void | |
1282 | gc_mark_symbol_for_shlib(Symbol* sym); | |
1283 | ||
1284 | // During garbage collection, this keeps sections that correspond to | |
1285 | // symbols seen in dynamic objects. | |
1286 | inline void | |
1287 | gc_mark_dyn_syms(Symbol* sym); | |
1288 | ||
dbe717ef | 1289 | // Add COUNT external symbols from the relocatable object RELOBJ to |
d491d34e ILT |
1290 | // the symbol table. SYMS is the symbols, SYMNDX_OFFSET is the |
1291 | // offset in the symbol table of the first symbol, SYM_NAMES is | |
1292 | // their names, SYM_NAME_SIZE is the size of SYM_NAMES. This sets | |
92de84a6 ILT |
1293 | // SYMPOINTERS to point to the symbols in the symbol table. It sets |
1294 | // *DEFINED to the number of defined symbols. | |
14bfc3f5 ILT |
1295 | template<int size, bool big_endian> |
1296 | void | |
dbe717ef ILT |
1297 | add_from_relobj(Sized_relobj<size, big_endian>* relobj, |
1298 | const unsigned char* syms, size_t count, | |
d491d34e ILT |
1299 | size_t symndx_offset, const char* sym_names, |
1300 | size_t sym_name_size, | |
92de84a6 ILT |
1301 | typename Sized_relobj<size, big_endian>::Symbols*, |
1302 | size_t* defined); | |
89fc3421 CC |
1303 | |
1304 | // Add one external symbol from the plugin object OBJ to the symbol table. | |
1305 | // Returns a pointer to the resolved symbol in the symbol table. | |
1306 | template<int size, bool big_endian> | |
1307 | Symbol* | |
1308 | add_from_pluginobj(Sized_pluginobj<size, big_endian>* obj, | |
1309 | const char* name, const char* ver, | |
1310 | elfcpp::Sym<size, big_endian>* sym); | |
14bfc3f5 | 1311 | |
dbe717ef ILT |
1312 | // Add COUNT dynamic symbols from the dynamic object DYNOBJ to the |
1313 | // symbol table. SYMS is the symbols. SYM_NAMES is their names. | |
1314 | // SYM_NAME_SIZE is the size of SYM_NAMES. The other parameters are | |
1315 | // symbol version data. | |
1316 | template<int size, bool big_endian> | |
1317 | void | |
1318 | add_from_dynobj(Sized_dynobj<size, big_endian>* dynobj, | |
1319 | const unsigned char* syms, size_t count, | |
1320 | const char* sym_names, size_t sym_name_size, | |
1321 | const unsigned char* versym, size_t versym_size, | |
92de84a6 ILT |
1322 | const std::vector<const char*>*, |
1323 | typename Sized_relobj<size, big_endian>::Symbols*, | |
1324 | size_t* defined); | |
dbe717ef | 1325 | |
ead1e424 ILT |
1326 | // Define a special symbol based on an Output_data. It is a |
1327 | // multiple definition error if this symbol is already defined. | |
14b31740 | 1328 | Symbol* |
99fff23b | 1329 | define_in_output_data(const char* name, const char* version, Defined, |
14b31740 | 1330 | Output_data*, uint64_t value, uint64_t symsize, |
ead1e424 ILT |
1331 | elfcpp::STT type, elfcpp::STB binding, |
1332 | elfcpp::STV visibility, unsigned char nonvis, | |
1333 | bool offset_is_from_end, bool only_if_ref); | |
1334 | ||
1335 | // Define a special symbol based on an Output_segment. It is a | |
1336 | // multiple definition error if this symbol is already defined. | |
14b31740 | 1337 | Symbol* |
99fff23b | 1338 | define_in_output_segment(const char* name, const char* version, Defined, |
9b07f471 | 1339 | Output_segment*, uint64_t value, uint64_t symsize, |
ead1e424 ILT |
1340 | elfcpp::STT type, elfcpp::STB binding, |
1341 | elfcpp::STV visibility, unsigned char nonvis, | |
1342 | Symbol::Segment_offset_base, bool only_if_ref); | |
1343 | ||
1344 | // Define a special symbol with a constant value. It is a multiple | |
1345 | // definition error if this symbol is already defined. | |
14b31740 | 1346 | Symbol* |
99fff23b | 1347 | define_as_constant(const char* name, const char* version, Defined, |
14b31740 ILT |
1348 | uint64_t value, uint64_t symsize, elfcpp::STT type, |
1349 | elfcpp::STB binding, elfcpp::STV visibility, | |
caa9d5d9 ILT |
1350 | unsigned char nonvis, bool only_if_ref, |
1351 | bool force_override); | |
ead1e424 | 1352 | |
a445fddf ILT |
1353 | // Define a set of symbols in output sections. If ONLY_IF_REF is |
1354 | // true, only define them if they are referenced. | |
ead1e424 | 1355 | void |
a445fddf ILT |
1356 | define_symbols(const Layout*, int count, const Define_symbol_in_section*, |
1357 | bool only_if_ref); | |
ead1e424 | 1358 | |
a445fddf ILT |
1359 | // Define a set of symbols in output segments. If ONLY_IF_REF is |
1360 | // true, only defined them if they are referenced. | |
ead1e424 | 1361 | void |
a445fddf ILT |
1362 | define_symbols(const Layout*, int count, const Define_symbol_in_segment*, |
1363 | bool only_if_ref); | |
ead1e424 | 1364 | |
46fe1623 ILT |
1365 | // Define SYM using a COPY reloc. POSD is the Output_data where the |
1366 | // symbol should be defined--typically a .dyn.bss section. VALUE is | |
1367 | // the offset within POSD. | |
1368 | template<int size> | |
1369 | void | |
9b07f471 | 1370 | define_with_copy_reloc(Sized_symbol<size>* sym, Output_data* posd, |
fe8718a4 | 1371 | typename elfcpp::Elf_types<size>::Elf_Addr); |
46fe1623 | 1372 | |
61ba1cf9 ILT |
1373 | // Look up a symbol. |
1374 | Symbol* | |
1375 | lookup(const char*, const char* version = NULL) const; | |
1376 | ||
14bfc3f5 | 1377 | // Return the real symbol associated with the forwarder symbol FROM. |
bae7f79e | 1378 | Symbol* |
c06b7b0b | 1379 | resolve_forwards(const Symbol* from) const; |
bae7f79e | 1380 | |
1564db8d ILT |
1381 | // Return the sized version of a symbol in this table. |
1382 | template<int size> | |
1383 | Sized_symbol<size>* | |
7d1a9ebb | 1384 | get_sized_symbol(Symbol*) const; |
1564db8d ILT |
1385 | |
1386 | template<int size> | |
1387 | const Sized_symbol<size>* | |
7d1a9ebb | 1388 | get_sized_symbol(const Symbol*) const; |
54dc6425 | 1389 | |
ead1e424 | 1390 | // Return the count of undefined symbols seen. |
114dfbe1 | 1391 | size_t |
ead1e424 ILT |
1392 | saw_undefined() const |
1393 | { return this->saw_undefined_; } | |
1394 | ||
1395 | // Allocate the common symbols | |
1396 | void | |
7d9e3d98 | 1397 | allocate_commons(Layout*, Mapfile*); |
ead1e424 | 1398 | |
cb295612 ILT |
1399 | // Add a warning for symbol NAME in object OBJ. WARNING is the text |
1400 | // of the warning. | |
f6ce93d6 | 1401 | void |
cb295612 ILT |
1402 | add_warning(const char* name, Object* obj, const std::string& warning) |
1403 | { this->warnings_.add_warning(this, name, obj, warning); } | |
f6ce93d6 ILT |
1404 | |
1405 | // Canonicalize a symbol name for use in the hash table. | |
1406 | const char* | |
1407 | canonicalize_name(const char* name) | |
cfd73a4e | 1408 | { return this->namepool_.add(name, true, NULL); } |
f6ce93d6 ILT |
1409 | |
1410 | // Possibly issue a warning for a reference to SYM at LOCATION which | |
1411 | // is in OBJ. | |
75f2446e | 1412 | template<int size, bool big_endian> |
f6ce93d6 | 1413 | void |
75f2446e ILT |
1414 | issue_warning(const Symbol* sym, |
1415 | const Relocate_info<size, big_endian>* relinfo, | |
1416 | size_t relnum, off_t reloffset) const | |
1417 | { this->warnings_.issue_warning(sym, relinfo, relnum, reloffset); } | |
f6ce93d6 | 1418 | |
70e654ba ILT |
1419 | // Check candidate_odr_violations_ to find symbols with the same name |
1420 | // but apparently different definitions (different source-file/line-no). | |
1421 | void | |
17a1d0a9 | 1422 | detect_odr_violations(const Task*, const char* output_file_name) const; |
70e654ba | 1423 | |
f3e9c5c5 ILT |
1424 | // Add any undefined symbols named on the command line to the symbol |
1425 | // table. | |
1426 | void | |
88a4108b | 1427 | add_undefined_symbols_from_command_line(Layout*); |
f3e9c5c5 | 1428 | |
46fe1623 ILT |
1429 | // SYM is defined using a COPY reloc. Return the dynamic object |
1430 | // where the original definition was found. | |
1431 | Dynobj* | |
1432 | get_copy_source(const Symbol* sym) const; | |
1433 | ||
a3ad94ed ILT |
1434 | // Set the dynamic symbol indexes. INDEX is the index of the first |
1435 | // global dynamic symbol. Pointers to the symbols are stored into | |
1436 | // the vector. The names are stored into the Stringpool. This | |
1437 | // returns an updated dynamic symbol index. | |
1438 | unsigned int | |
9b07f471 ILT |
1439 | set_dynsym_indexes(unsigned int index, std::vector<Symbol*>*, |
1440 | Stringpool*, Versions*); | |
a3ad94ed | 1441 | |
75f65a3e | 1442 | // Finalize the symbol table after we have set the final addresses |
c06b7b0b | 1443 | // of all the input sections. This sets the final symbol indexes, |
55a93433 ILT |
1444 | // values and adds the names to *POOL. *PLOCAL_SYMCOUNT is the |
1445 | // index of the first global symbol. OFF is the file offset of the | |
1446 | // global symbol table, DYNOFF is the offset of the globals in the | |
1447 | // dynamic symbol table, DYN_GLOBAL_INDEX is the index of the first | |
1448 | // global dynamic symbol, and DYNCOUNT is the number of global | |
1449 | // dynamic symbols. This records the parameters, and returns the | |
1450 | // new file offset. It updates *PLOCAL_SYMCOUNT if it created any | |
1451 | // local symbols. | |
75f65a3e | 1452 | off_t |
55a93433 ILT |
1453 | finalize(off_t off, off_t dynoff, size_t dyn_global_index, size_t dyncount, |
1454 | Stringpool* pool, unsigned int *plocal_symcount); | |
1564db8d | 1455 | |
c0a62865 DK |
1456 | // Status code of Symbol_table::compute_final_value. |
1457 | enum Compute_final_value_status | |
1458 | { | |
1459 | // No error. | |
1460 | CFVS_OK, | |
1461 | // Unspported symbol section. | |
1462 | CFVS_UNSUPPORTED_SYMBOL_SECTION, | |
1463 | // No output section. | |
1464 | CFVS_NO_OUTPUT_SECTION | |
1465 | }; | |
1466 | ||
1467 | // Compute the final value of SYM and store status in location PSTATUS. | |
1468 | // During relaxation, this may be called multiple times for a symbol to | |
1469 | // compute its would-be final value in each relaxation pass. | |
1470 | ||
1471 | template<int size> | |
1472 | typename Sized_symbol<size>::Value_type | |
1473 | compute_final_value(const Sized_symbol<size>* sym, | |
1474 | Compute_final_value_status* pstatus) const; | |
1475 | ||
09ec0418 CC |
1476 | // Return the index of the first global symbol. |
1477 | unsigned int | |
1478 | first_global_index() const | |
1479 | { return this->first_global_index_; } | |
1480 | ||
1481 | // Return the total number of symbols in the symbol table. | |
1482 | unsigned int | |
1483 | output_count() const | |
1484 | { return this->output_count_; } | |
1485 | ||
61ba1cf9 ILT |
1486 | // Write out the global symbols. |
1487 | void | |
fd9d194f | 1488 | write_globals(const Stringpool*, const Stringpool*, |
d491d34e | 1489 | Output_symtab_xindex*, Output_symtab_xindex*, |
16649710 | 1490 | Output_file*) const; |
61ba1cf9 | 1491 | |
a3ad94ed ILT |
1492 | // Write out a section symbol. Return the updated offset. |
1493 | void | |
d491d34e ILT |
1494 | write_section_symbol(const Output_section*, Output_symtab_xindex*, |
1495 | Output_file*, off_t) const; | |
a3ad94ed | 1496 | |
0e70b911 CC |
1497 | // Loop over all symbols, applying the function F to each. |
1498 | template<int size, typename F> | |
1499 | void | |
1500 | for_all_symbols(F f) const | |
1501 | { | |
1502 | for (Symbol_table_type::const_iterator p = this->table_.begin(); | |
1503 | p != this->table_.end(); | |
1504 | ++p) | |
1505 | { | |
1506 | Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(p->second); | |
1507 | f(sym); | |
1508 | } | |
1509 | } | |
1510 | ||
abaa3995 ILT |
1511 | // Dump statistical information to stderr. |
1512 | void | |
1513 | print_stats() const; | |
1514 | ||
09124467 ILT |
1515 | // Return the version script information. |
1516 | const Version_script_info& | |
1517 | version_script() const | |
1518 | { return version_script_; } | |
1519 | ||
bae7f79e ILT |
1520 | private: |
1521 | Symbol_table(const Symbol_table&); | |
1522 | Symbol_table& operator=(const Symbol_table&); | |
1523 | ||
155a0dd7 ILT |
1524 | // The type of the list of common symbols. |
1525 | typedef std::vector<Symbol*> Commons_type; | |
1526 | ||
8c500701 ILT |
1527 | // The type of the symbol hash table. |
1528 | ||
1529 | typedef std::pair<Stringpool::Key, Stringpool::Key> Symbol_table_key; | |
1530 | ||
1531 | struct Symbol_table_hash | |
1532 | { | |
1533 | size_t | |
1534 | operator()(const Symbol_table_key&) const; | |
1535 | }; | |
1536 | ||
1537 | struct Symbol_table_eq | |
1538 | { | |
1539 | bool | |
1540 | operator()(const Symbol_table_key&, const Symbol_table_key&) const; | |
1541 | }; | |
1542 | ||
1543 | typedef Unordered_map<Symbol_table_key, Symbol*, Symbol_table_hash, | |
1544 | Symbol_table_eq> Symbol_table_type; | |
1545 | ||
14bfc3f5 ILT |
1546 | // Make FROM a forwarder symbol to TO. |
1547 | void | |
1548 | make_forwarder(Symbol* from, Symbol* to); | |
1549 | ||
1550 | // Add a symbol. | |
1551 | template<int size, bool big_endian> | |
aeddab66 | 1552 | Sized_symbol<size>* |
f0641a0b ILT |
1553 | add_from_object(Object*, const char *name, Stringpool::Key name_key, |
1554 | const char *version, Stringpool::Key version_key, | |
70e654ba | 1555 | bool def, const elfcpp::Sym<size, big_endian>& sym, |
d491d34e ILT |
1556 | unsigned int st_shndx, bool is_ordinary, |
1557 | unsigned int orig_st_shndx); | |
14bfc3f5 | 1558 | |
8c500701 ILT |
1559 | // Define a default symbol. |
1560 | template<int size, bool big_endian> | |
1561 | void | |
1562 | define_default_version(Sized_symbol<size>*, bool, | |
1563 | Symbol_table_type::iterator); | |
1564 | ||
14bfc3f5 ILT |
1565 | // Resolve symbols. |
1566 | template<int size, bool big_endian> | |
aeddab66 | 1567 | void |
1564db8d ILT |
1568 | resolve(Sized_symbol<size>* to, |
1569 | const elfcpp::Sym<size, big_endian>& sym, | |
d491d34e ILT |
1570 | unsigned int st_shndx, bool is_ordinary, |
1571 | unsigned int orig_st_shndx, | |
14b31740 | 1572 | Object*, const char* version); |
14bfc3f5 | 1573 | |
1564db8d | 1574 | template<int size, bool big_endian> |
aeddab66 | 1575 | void |
95d14cd3 | 1576 | resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from); |
14b31740 | 1577 | |
0602e05a ILT |
1578 | // Record that a symbol is forced to be local by a version script or |
1579 | // by visibility. | |
55a93433 ILT |
1580 | void |
1581 | force_local(Symbol*); | |
1582 | ||
0864d551 ILT |
1583 | // Adjust NAME and *NAME_KEY for wrapping. |
1584 | const char* | |
029ba973 | 1585 | wrap_symbol(const char* name, Stringpool::Key* name_key); |
0864d551 | 1586 | |
86f2e683 ILT |
1587 | // Whether we should override a symbol, based on flags in |
1588 | // resolve.cc. | |
1589 | static bool | |
ce279a62 | 1590 | should_override(const Symbol*, unsigned int, Defined, Object*, bool*, bool*); |
86f2e683 | 1591 | |
1ae4d23b ILT |
1592 | // Report a problem in symbol resolution. |
1593 | static void | |
1594 | report_resolve_problem(bool is_error, const char* msg, const Symbol* to, | |
99fff23b | 1595 | Defined, Object* object); |
1ae4d23b | 1596 | |
aeddab66 ILT |
1597 | // Override a symbol. |
1598 | template<int size, bool big_endian> | |
1599 | void | |
1600 | override(Sized_symbol<size>* tosym, | |
1601 | const elfcpp::Sym<size, big_endian>& fromsym, | |
d491d34e | 1602 | unsigned int st_shndx, bool is_ordinary, |
aeddab66 ILT |
1603 | Object* object, const char* version); |
1604 | ||
86f2e683 ILT |
1605 | // Whether we should override a symbol with a special symbol which |
1606 | // is automatically defined by the linker. | |
1607 | static bool | |
99fff23b | 1608 | should_override_with_special(const Symbol*, Defined); |
86f2e683 | 1609 | |
aeddab66 ILT |
1610 | // Override a symbol with a special symbol. |
1611 | template<int size> | |
1612 | void | |
1613 | override_with_special(Sized_symbol<size>* tosym, | |
1614 | const Sized_symbol<size>* fromsym); | |
1615 | ||
1616 | // Record all weak alias sets for a dynamic object. | |
1617 | template<int size> | |
1618 | void | |
1619 | record_weak_aliases(std::vector<Sized_symbol<size>*>*); | |
1620 | ||
14b31740 ILT |
1621 | // Define a special symbol. |
1622 | template<int size, bool big_endian> | |
1623 | Sized_symbol<size>* | |
9b07f471 | 1624 | define_special_symbol(const char** pname, const char** pversion, |
8c500701 ILT |
1625 | bool only_if_ref, Sized_symbol<size>** poldsym, |
1626 | bool* resolve_oldsym); | |
14bfc3f5 | 1627 | |
ead1e424 ILT |
1628 | // Define a symbol in an Output_data, sized version. |
1629 | template<int size> | |
14b31740 | 1630 | Sized_symbol<size>* |
99fff23b ILT |
1631 | do_define_in_output_data(const char* name, const char* version, Defined, |
1632 | Output_data*, | |
ead1e424 ILT |
1633 | typename elfcpp::Elf_types<size>::Elf_Addr value, |
1634 | typename elfcpp::Elf_types<size>::Elf_WXword ssize, | |
1635 | elfcpp::STT type, elfcpp::STB binding, | |
1636 | elfcpp::STV visibility, unsigned char nonvis, | |
1637 | bool offset_is_from_end, bool only_if_ref); | |
1638 | ||
1639 | // Define a symbol in an Output_segment, sized version. | |
1640 | template<int size> | |
14b31740 | 1641 | Sized_symbol<size>* |
ead1e424 | 1642 | do_define_in_output_segment( |
99fff23b | 1643 | const char* name, const char* version, Defined, Output_segment* os, |
ead1e424 ILT |
1644 | typename elfcpp::Elf_types<size>::Elf_Addr value, |
1645 | typename elfcpp::Elf_types<size>::Elf_WXword ssize, | |
1646 | elfcpp::STT type, elfcpp::STB binding, | |
1647 | elfcpp::STV visibility, unsigned char nonvis, | |
1648 | Symbol::Segment_offset_base offset_base, bool only_if_ref); | |
1649 | ||
1650 | // Define a symbol as a constant, sized version. | |
1651 | template<int size> | |
14b31740 | 1652 | Sized_symbol<size>* |
ead1e424 | 1653 | do_define_as_constant( |
99fff23b | 1654 | const char* name, const char* version, Defined, |
ead1e424 ILT |
1655 | typename elfcpp::Elf_types<size>::Elf_Addr value, |
1656 | typename elfcpp::Elf_types<size>::Elf_WXword ssize, | |
1657 | elfcpp::STT type, elfcpp::STB binding, | |
1658 | elfcpp::STV visibility, unsigned char nonvis, | |
caa9d5d9 | 1659 | bool only_if_ref, bool force_override); |
ead1e424 | 1660 | |
f3e9c5c5 ILT |
1661 | // Add any undefined symbols named on the command line to the symbol |
1662 | // table, sized version. | |
1663 | template<int size> | |
1664 | void | |
88a4108b ILT |
1665 | do_add_undefined_symbols_from_command_line(Layout*); |
1666 | ||
1667 | // Add one undefined symbol. | |
1668 | template<int size> | |
1669 | void | |
1670 | add_undefined_symbol_from_command_line(const char* name); | |
f3e9c5c5 | 1671 | |
8a5e3e08 ILT |
1672 | // Types of common symbols. |
1673 | ||
1674 | enum Commons_section_type | |
1675 | { | |
1676 | COMMONS_NORMAL, | |
1677 | COMMONS_TLS, | |
1678 | COMMONS_SMALL, | |
1679 | COMMONS_LARGE | |
1680 | }; | |
1681 | ||
ead1e424 ILT |
1682 | // Allocate the common symbols, sized version. |
1683 | template<int size> | |
1684 | void | |
fc59c572 | 1685 | do_allocate_commons(Layout*, Mapfile*, Sort_commons_order); |
155a0dd7 ILT |
1686 | |
1687 | // Allocate the common symbols from one list. | |
1688 | template<int size> | |
1689 | void | |
8a5e3e08 | 1690 | do_allocate_commons_list(Layout*, Commons_section_type, Commons_type*, |
fc59c572 | 1691 | Mapfile*, Sort_commons_order); |
ead1e424 | 1692 | |
70e654ba ILT |
1693 | // Implement detect_odr_violations. |
1694 | template<int size, bool big_endian> | |
1695 | void | |
1696 | sized_detect_odr_violations() const; | |
1697 | ||
75f65a3e ILT |
1698 | // Finalize symbols specialized for size. |
1699 | template<int size> | |
1700 | off_t | |
55a93433 ILT |
1701 | sized_finalize(off_t, Stringpool*, unsigned int*); |
1702 | ||
1703 | // Finalize a symbol. Return whether it should be added to the | |
1704 | // symbol table. | |
1705 | template<int size> | |
1706 | bool | |
1707 | sized_finalize_symbol(Symbol*); | |
1708 | ||
1709 | // Add a symbol the final symtab by setting its index. | |
1710 | template<int size> | |
1711 | void | |
1712 | add_to_final_symtab(Symbol*, Stringpool*, unsigned int* pindex, off_t* poff); | |
75f65a3e | 1713 | |
61ba1cf9 ILT |
1714 | // Write globals specialized for size and endianness. |
1715 | template<int size, bool big_endian> | |
1716 | void | |
fd9d194f ILT |
1717 | sized_write_globals(const Stringpool*, const Stringpool*, |
1718 | Output_symtab_xindex*, Output_symtab_xindex*, | |
1719 | Output_file*) const; | |
16649710 ILT |
1720 | |
1721 | // Write out a symbol to P. | |
1722 | template<int size, bool big_endian> | |
1723 | void | |
ab5c9e90 ILT |
1724 | sized_write_symbol(Sized_symbol<size>*, |
1725 | typename elfcpp::Elf_types<size>::Elf_Addr value, | |
ce279a62 | 1726 | unsigned int shndx, elfcpp::STB, |
7d1a9ebb | 1727 | const Stringpool*, unsigned char* p) const; |
61ba1cf9 | 1728 | |
9a2d6984 ILT |
1729 | // Possibly warn about an undefined symbol from a dynamic object. |
1730 | void | |
fd9d194f | 1731 | warn_about_undefined_dynobj_symbol(Symbol*) const; |
9a2d6984 | 1732 | |
a3ad94ed ILT |
1733 | // Write out a section symbol, specialized for size and endianness. |
1734 | template<int size, bool big_endian> | |
1735 | void | |
d491d34e ILT |
1736 | sized_write_section_symbol(const Output_section*, Output_symtab_xindex*, |
1737 | Output_file*, off_t) const; | |
a3ad94ed | 1738 | |
55a93433 ILT |
1739 | // The type of the list of symbols which have been forced local. |
1740 | typedef std::vector<Symbol*> Forced_locals; | |
1741 | ||
46fe1623 ILT |
1742 | // A map from symbols with COPY relocs to the dynamic objects where |
1743 | // they are defined. | |
1744 | typedef Unordered_map<const Symbol*, Dynobj*> Copied_symbol_dynobjs; | |
1745 | ||
70e654ba ILT |
1746 | // A map from symbol name (as a pointer into the namepool) to all |
1747 | // the locations the symbols is (weakly) defined (and certain other | |
1748 | // conditions are met). This map will be used later to detect | |
1749 | // possible One Definition Rule (ODR) violations. | |
1750 | struct Symbol_location | |
1751 | { | |
1752 | Object* object; // Object where the symbol is defined. | |
1753 | unsigned int shndx; // Section-in-object where the symbol is defined. | |
1754 | off_t offset; // Offset-in-section where the symbol is defined. | |
1755 | bool operator==(const Symbol_location& that) const | |
1756 | { | |
1757 | return (this->object == that.object | |
1758 | && this->shndx == that.shndx | |
1759 | && this->offset == that.offset); | |
1760 | } | |
1761 | }; | |
1762 | ||
1763 | struct Symbol_location_hash | |
1764 | { | |
1765 | size_t operator()(const Symbol_location& loc) const | |
1766 | { return reinterpret_cast<uintptr_t>(loc.object) ^ loc.offset ^ loc.shndx; } | |
1767 | }; | |
1768 | ||
1769 | typedef Unordered_map<const char*, | |
1770 | Unordered_set<Symbol_location, Symbol_location_hash> > | |
1771 | Odr_map; | |
1772 | ||
ead1e424 ILT |
1773 | // We increment this every time we see a new undefined symbol, for |
1774 | // use in archive groups. | |
114dfbe1 | 1775 | size_t saw_undefined_; |
c06b7b0b ILT |
1776 | // The index of the first global symbol in the output file. |
1777 | unsigned int first_global_index_; | |
75f65a3e ILT |
1778 | // The file offset within the output symtab section where we should |
1779 | // write the table. | |
1780 | off_t offset_; | |
61ba1cf9 | 1781 | // The number of global symbols we want to write out. |
55a93433 | 1782 | unsigned int output_count_; |
16649710 ILT |
1783 | // The file offset of the global dynamic symbols, or 0 if none. |
1784 | off_t dynamic_offset_; | |
16649710 ILT |
1785 | // The index of the first global dynamic symbol. |
1786 | unsigned int first_dynamic_global_index_; | |
16649710 | 1787 | // The number of global dynamic symbols, or 0 if none. |
55a93433 | 1788 | unsigned int dynamic_count_; |
54dc6425 | 1789 | // The symbol hash table. |
14bfc3f5 | 1790 | Symbol_table_type table_; |
54dc6425 ILT |
1791 | // A pool of symbol names. This is used for all global symbols. |
1792 | // Entries in the hash table point into this pool. | |
14bfc3f5 | 1793 | Stringpool namepool_; |
14bfc3f5 | 1794 | // Forwarding symbols. |
c06b7b0b | 1795 | Unordered_map<const Symbol*, Symbol*> forwarders_; |
aeddab66 ILT |
1796 | // Weak aliases. A symbol in this list points to the next alias. |
1797 | // The aliases point to each other in a circular list. | |
1798 | Unordered_map<Symbol*, Symbol*> weak_aliases_; | |
ead1e424 ILT |
1799 | // We don't expect there to be very many common symbols, so we keep |
1800 | // a list of them. When we find a common symbol we add it to this | |
1801 | // list. It is possible that by the time we process the list the | |
1802 | // symbol is no longer a common symbol. It may also have become a | |
1803 | // forwarder. | |
1804 | Commons_type commons_; | |
155a0dd7 ILT |
1805 | // This is like the commons_ field, except that it holds TLS common |
1806 | // symbols. | |
1807 | Commons_type tls_commons_; | |
8a5e3e08 ILT |
1808 | // This is for small common symbols. |
1809 | Commons_type small_commons_; | |
1810 | // This is for large common symbols. | |
1811 | Commons_type large_commons_; | |
55a93433 ILT |
1812 | // A list of symbols which have been forced to be local. We don't |
1813 | // expect there to be very many of them, so we keep a list of them | |
1814 | // rather than walking the whole table to find them. | |
1815 | Forced_locals forced_locals_; | |
f6ce93d6 ILT |
1816 | // Manage symbol warnings. |
1817 | Warnings warnings_; | |
70e654ba ILT |
1818 | // Manage potential One Definition Rule (ODR) violations. |
1819 | Odr_map candidate_odr_violations_; | |
1820 | ||
46fe1623 ILT |
1821 | // When we emit a COPY reloc for a symbol, we define it in an |
1822 | // Output_data. When it's time to emit version information for it, | |
1823 | // we need to know the dynamic object in which we found the original | |
1824 | // definition. This maps symbols with COPY relocs to the dynamic | |
1825 | // object where they were defined. | |
1826 | Copied_symbol_dynobjs copied_symbol_dynobjs_; | |
09124467 ILT |
1827 | // Information parsed from the version script, if any. |
1828 | const Version_script_info& version_script_; | |
6d03d481 | 1829 | Garbage_collection* gc_; |
ef15dade | 1830 | Icf* icf_; |
bae7f79e ILT |
1831 | }; |
1832 | ||
1564db8d ILT |
1833 | // We inline get_sized_symbol for efficiency. |
1834 | ||
1835 | template<int size> | |
1836 | Sized_symbol<size>* | |
7d1a9ebb | 1837 | Symbol_table::get_sized_symbol(Symbol* sym) const |
1564db8d | 1838 | { |
8851ecca | 1839 | gold_assert(size == parameters->target().get_size()); |
1564db8d ILT |
1840 | return static_cast<Sized_symbol<size>*>(sym); |
1841 | } | |
1842 | ||
1843 | template<int size> | |
1844 | const Sized_symbol<size>* | |
7d1a9ebb | 1845 | Symbol_table::get_sized_symbol(const Symbol* sym) const |
1564db8d | 1846 | { |
8851ecca | 1847 | gold_assert(size == parameters->target().get_size()); |
1564db8d ILT |
1848 | return static_cast<const Sized_symbol<size>*>(sym); |
1849 | } | |
1850 | ||
bae7f79e ILT |
1851 | } // End namespace gold. |
1852 | ||
1853 | #endif // !defined(GOLD_SYMTAB_H) |