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bae7f79e ILT |
1 | // symtab.h -- the gold symbol table -*- C++ -*- |
2 | ||
6cb15b7f ILT |
3 | // Copyright 2006, 2007 Free Software Foundation, Inc. |
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 | ||
bae7f79e ILT |
26 | #include <string> |
27 | #include <utility> | |
ead1e424 | 28 | #include <vector> |
bae7f79e ILT |
29 | |
30 | #include "elfcpp.h" | |
7e1edb90 | 31 | #include "parameters.h" |
14bfc3f5 | 32 | #include "stringpool.h" |
f6ce93d6 | 33 | #include "object.h" |
bae7f79e ILT |
34 | |
35 | #ifndef GOLD_SYMTAB_H | |
36 | #define GOLD_SYMTAB_H | |
37 | ||
38 | namespace gold | |
39 | { | |
40 | ||
14bfc3f5 | 41 | class Object; |
f6ce93d6 | 42 | class Relobj; |
dbe717ef ILT |
43 | template<int size, bool big_endian> |
44 | class Sized_relobj; | |
f6ce93d6 | 45 | class Dynobj; |
dbe717ef ILT |
46 | template<int size, bool big_endian> |
47 | class Sized_dynobj; | |
14b31740 | 48 | class Versions; |
09124467 | 49 | class Version_script_info; |
9a2d6984 | 50 | class Input_objects; |
ead1e424 | 51 | class Output_data; |
a3ad94ed | 52 | class Output_section; |
ead1e424 | 53 | class Output_segment; |
61ba1cf9 ILT |
54 | class Output_file; |
55 | class Target; | |
14bfc3f5 | 56 | |
14bfc3f5 ILT |
57 | // The base class of an entry in the symbol table. The symbol table |
58 | // can have a lot of entries, so we don't want this class to big. | |
59 | // Size dependent fields can be found in the template class | |
60 | // Sized_symbol. Targets may support their own derived classes. | |
bae7f79e | 61 | |
bae7f79e ILT |
62 | class Symbol |
63 | { | |
64 | public: | |
ead1e424 ILT |
65 | // Because we want the class to be small, we don't use any virtual |
66 | // functions. But because symbols can be defined in different | |
67 | // places, we need to classify them. This enum is the different | |
68 | // sources of symbols we support. | |
69 | enum Source | |
70 | { | |
f6ce93d6 ILT |
71 | // Symbol defined in a relocatable or dynamic input file--this is |
72 | // the most common case. | |
ead1e424 ILT |
73 | FROM_OBJECT, |
74 | // Symbol defined in an Output_data, a special section created by | |
75 | // the target. | |
76 | IN_OUTPUT_DATA, | |
77 | // Symbol defined in an Output_segment, with no associated | |
78 | // section. | |
79 | IN_OUTPUT_SEGMENT, | |
80 | // Symbol value is constant. | |
81 | CONSTANT | |
82 | }; | |
83 | ||
84 | // When the source is IN_OUTPUT_SEGMENT, we need to describe what | |
85 | // the offset means. | |
86 | enum Segment_offset_base | |
87 | { | |
88 | // From the start of the segment. | |
89 | SEGMENT_START, | |
90 | // From the end of the segment. | |
91 | SEGMENT_END, | |
92 | // From the filesz of the segment--i.e., after the loaded bytes | |
93 | // but before the bytes which are allocated but zeroed. | |
94 | SEGMENT_BSS | |
95 | }; | |
96 | ||
14bfc3f5 ILT |
97 | // Return the symbol name. |
98 | const char* | |
99 | name() const | |
100 | { return this->name_; } | |
101 | ||
a2b1aa12 ILT |
102 | // Return the (ANSI) demangled version of the name, if |
103 | // parameters.demangle() is true. Otherwise, return the name. This | |
104 | // is intended to be used only for logging errors, so it's not | |
105 | // super-efficient. | |
106 | std::string | |
107 | demangled_name() const; | |
108 | ||
14bfc3f5 ILT |
109 | // Return the symbol version. This will return NULL for an |
110 | // unversioned symbol. | |
111 | const char* | |
112 | version() const | |
113 | { return this->version_; } | |
114 | ||
09124467 ILT |
115 | // Return whether this version is the default for this symbol name |
116 | // (eg, "foo@@V2" is a default version; "foo@V1" is not). Only | |
117 | // meaningful for versioned symbols. | |
118 | bool | |
119 | is_default() const | |
120 | { | |
121 | gold_assert(this->version_ != NULL); | |
122 | return this->is_def_; | |
123 | } | |
124 | ||
125 | // Set whether this version is the default for this symbol name. | |
126 | void | |
127 | set_is_default(bool def) | |
128 | { this->is_def_ = def; } | |
129 | ||
ead1e424 ILT |
130 | // Return the symbol source. |
131 | Source | |
132 | source() const | |
133 | { return this->source_; } | |
134 | ||
14bfc3f5 ILT |
135 | // Return the object with which this symbol is associated. |
136 | Object* | |
137 | object() const | |
ead1e424 | 138 | { |
a3ad94ed | 139 | gold_assert(this->source_ == FROM_OBJECT); |
ead1e424 ILT |
140 | return this->u_.from_object.object; |
141 | } | |
142 | ||
f6ce93d6 ILT |
143 | // Return the index of the section in the input relocatable or |
144 | // dynamic object file. | |
ead1e424 | 145 | unsigned int |
16649710 | 146 | shndx() const |
ead1e424 | 147 | { |
a3ad94ed | 148 | gold_assert(this->source_ == FROM_OBJECT); |
16649710 | 149 | return this->u_.from_object.shndx; |
ead1e424 ILT |
150 | } |
151 | ||
152 | // Return the output data section with which this symbol is | |
153 | // associated, if the symbol was specially defined with respect to | |
154 | // an output data section. | |
155 | Output_data* | |
156 | output_data() const | |
157 | { | |
a3ad94ed | 158 | gold_assert(this->source_ == IN_OUTPUT_DATA); |
ead1e424 ILT |
159 | return this->u_.in_output_data.output_data; |
160 | } | |
161 | ||
162 | // If this symbol was defined with respect to an output data | |
163 | // section, return whether the value is an offset from end. | |
164 | bool | |
165 | offset_is_from_end() const | |
166 | { | |
a3ad94ed | 167 | gold_assert(this->source_ == IN_OUTPUT_DATA); |
ead1e424 ILT |
168 | return this->u_.in_output_data.offset_is_from_end; |
169 | } | |
170 | ||
171 | // Return the output segment with which this symbol is associated, | |
172 | // if the symbol was specially defined with respect to an output | |
173 | // segment. | |
174 | Output_segment* | |
175 | output_segment() const | |
176 | { | |
a3ad94ed | 177 | gold_assert(this->source_ == IN_OUTPUT_SEGMENT); |
ead1e424 ILT |
178 | return this->u_.in_output_segment.output_segment; |
179 | } | |
180 | ||
181 | // If this symbol was defined with respect to an output segment, | |
182 | // return the offset base. | |
183 | Segment_offset_base | |
184 | offset_base() const | |
185 | { | |
a3ad94ed | 186 | gold_assert(this->source_ == IN_OUTPUT_SEGMENT); |
ead1e424 ILT |
187 | return this->u_.in_output_segment.offset_base; |
188 | } | |
14bfc3f5 ILT |
189 | |
190 | // Return the symbol binding. | |
191 | elfcpp::STB | |
192 | binding() const | |
193 | { return this->binding_; } | |
194 | ||
1564db8d ILT |
195 | // Return the symbol type. |
196 | elfcpp::STT | |
197 | type() const | |
198 | { return this->type_; } | |
199 | ||
200 | // Return the symbol visibility. | |
201 | elfcpp::STV | |
202 | visibility() const | |
203 | { return this->visibility_; } | |
204 | ||
205 | // Return the non-visibility part of the st_other field. | |
206 | unsigned char | |
ead1e424 ILT |
207 | nonvis() const |
208 | { return this->nonvis_; } | |
14bfc3f5 | 209 | |
1564db8d ILT |
210 | // Return whether this symbol is a forwarder. This will never be |
211 | // true of a symbol found in the hash table, but may be true of | |
212 | // symbol pointers attached to object files. | |
213 | bool | |
214 | is_forwarder() const | |
215 | { return this->is_forwarder_; } | |
216 | ||
217 | // Mark this symbol as a forwarder. | |
218 | void | |
219 | set_forwarder() | |
220 | { this->is_forwarder_ = true; } | |
221 | ||
aeddab66 ILT |
222 | // Return whether this symbol has an alias in the weak aliases table |
223 | // in Symbol_table. | |
224 | bool | |
225 | has_alias() const | |
226 | { return this->has_alias_; } | |
227 | ||
228 | // Mark this symbol as having an alias. | |
229 | void | |
230 | set_has_alias() | |
231 | { this->has_alias_ = true; } | |
232 | ||
c06b7b0b ILT |
233 | // Return whether this symbol needs an entry in the dynamic symbol |
234 | // table. | |
235 | bool | |
236 | needs_dynsym_entry() const | |
429c1569 ILT |
237 | { |
238 | return (this->needs_dynsym_entry_ | |
239 | || (this->in_reg() && this->in_dyn())); | |
240 | } | |
c06b7b0b ILT |
241 | |
242 | // Mark this symbol as needing an entry in the dynamic symbol table. | |
243 | void | |
244 | set_needs_dynsym_entry() | |
245 | { this->needs_dynsym_entry_ = true; } | |
246 | ||
436ca963 ILT |
247 | // Return whether this symbol should be added to the dynamic symbol |
248 | // table. | |
249 | bool | |
250 | should_add_dynsym_entry() const; | |
251 | ||
008db82e ILT |
252 | // Return whether this symbol has been seen in a regular object. |
253 | bool | |
254 | in_reg() const | |
255 | { return this->in_reg_; } | |
256 | ||
257 | // Mark this symbol as having been seen in a regular object. | |
258 | void | |
259 | set_in_reg() | |
260 | { this->in_reg_ = true; } | |
261 | ||
1ebd95fd ILT |
262 | // Return whether this symbol has been seen in a dynamic object. |
263 | bool | |
264 | in_dyn() const | |
265 | { return this->in_dyn_; } | |
266 | ||
f6ce93d6 | 267 | // Mark this symbol as having been seen in a dynamic object. |
1564db8d ILT |
268 | void |
269 | set_in_dyn() | |
270 | { this->in_dyn_ = true; } | |
271 | ||
c06b7b0b ILT |
272 | // Return the index of this symbol in the output file symbol table. |
273 | // A value of -1U means that this symbol is not going into the | |
274 | // output file. This starts out as zero, and is set to a non-zero | |
275 | // value by Symbol_table::finalize. It is an error to ask for the | |
276 | // symbol table index before it has been set. | |
277 | unsigned int | |
278 | symtab_index() const | |
279 | { | |
a3ad94ed | 280 | gold_assert(this->symtab_index_ != 0); |
c06b7b0b ILT |
281 | return this->symtab_index_; |
282 | } | |
283 | ||
284 | // Set the index of the symbol in the output file symbol table. | |
285 | void | |
286 | set_symtab_index(unsigned int index) | |
287 | { | |
a3ad94ed | 288 | gold_assert(index != 0); |
c06b7b0b ILT |
289 | this->symtab_index_ = index; |
290 | } | |
291 | ||
a3ad94ed ILT |
292 | // Return whether this symbol already has an index in the output |
293 | // file symbol table. | |
294 | bool | |
295 | has_symtab_index() const | |
296 | { return this->symtab_index_ != 0; } | |
297 | ||
c06b7b0b ILT |
298 | // Return the index of this symbol in the dynamic symbol table. A |
299 | // value of -1U means that this symbol is not going into the dynamic | |
300 | // symbol table. This starts out as zero, and is set to a non-zero | |
301 | // during Layout::finalize. It is an error to ask for the dynamic | |
302 | // symbol table index before it has been set. | |
303 | unsigned int | |
304 | dynsym_index() const | |
305 | { | |
a3ad94ed | 306 | gold_assert(this->dynsym_index_ != 0); |
c06b7b0b ILT |
307 | return this->dynsym_index_; |
308 | } | |
309 | ||
310 | // Set the index of the symbol in the dynamic symbol table. | |
311 | void | |
312 | set_dynsym_index(unsigned int index) | |
313 | { | |
a3ad94ed | 314 | gold_assert(index != 0); |
c06b7b0b ILT |
315 | this->dynsym_index_ = index; |
316 | } | |
317 | ||
16649710 ILT |
318 | // Return whether this symbol already has an index in the dynamic |
319 | // symbol table. | |
320 | bool | |
321 | has_dynsym_index() const | |
322 | { return this->dynsym_index_ != 0; } | |
323 | ||
ead1e424 | 324 | // Return whether this symbol has an entry in the GOT section. |
07f397ab | 325 | // For a TLS symbol, this GOT entry will hold its tp-relative offset. |
92e059d8 | 326 | bool |
ead1e424 ILT |
327 | has_got_offset() const |
328 | { return this->has_got_offset_; } | |
329 | ||
330 | // Return the offset into the GOT section of this symbol. | |
331 | unsigned int | |
332 | got_offset() const | |
333 | { | |
a3ad94ed | 334 | gold_assert(this->has_got_offset()); |
ead1e424 ILT |
335 | return this->got_offset_; |
336 | } | |
337 | ||
338 | // Set the GOT offset of this symbol. | |
339 | void | |
340 | set_got_offset(unsigned int got_offset) | |
341 | { | |
342 | this->has_got_offset_ = true; | |
343 | this->got_offset_ = got_offset; | |
344 | } | |
345 | ||
07f397ab ILT |
346 | // Return whether this TLS symbol has an entry in the GOT section for |
347 | // its module index or, if NEED_PAIR is true, has a pair of entries | |
348 | // for its module index and dtv-relative offset. | |
349 | bool | |
350 | has_tls_got_offset(bool need_pair) const | |
351 | { | |
352 | return (this->has_tls_mod_got_offset_ | |
353 | && (!need_pair || this->has_tls_pair_got_offset_)); | |
354 | } | |
355 | ||
356 | // Return the offset into the GOT section for this symbol's TLS module | |
357 | // index or, if NEED_PAIR is true, for the pair of entries for the | |
358 | // module index and dtv-relative offset. | |
359 | unsigned int | |
360 | tls_got_offset(bool need_pair) const | |
361 | { | |
362 | gold_assert(this->has_tls_got_offset(need_pair)); | |
363 | return this->tls_mod_got_offset_; | |
364 | } | |
365 | ||
366 | // Set the GOT offset of this symbol. | |
367 | void | |
368 | set_tls_got_offset(unsigned int got_offset, bool have_pair) | |
369 | { | |
370 | this->has_tls_mod_got_offset_ = true; | |
371 | this->has_tls_pair_got_offset_ = have_pair; | |
372 | this->tls_mod_got_offset_ = got_offset; | |
373 | } | |
374 | ||
a3ad94ed | 375 | // Return whether this symbol has an entry in the PLT section. |
ead1e424 | 376 | bool |
a3ad94ed ILT |
377 | has_plt_offset() const |
378 | { return this->has_plt_offset_; } | |
379 | ||
380 | // Return the offset into the PLT section of this symbol. | |
381 | unsigned int | |
382 | plt_offset() const | |
383 | { | |
384 | gold_assert(this->has_plt_offset()); | |
385 | return this->plt_offset_; | |
386 | } | |
387 | ||
388 | // Set the PLT offset of this symbol. | |
389 | void | |
390 | set_plt_offset(unsigned int plt_offset) | |
391 | { | |
392 | this->has_plt_offset_ = true; | |
393 | this->plt_offset_ = plt_offset; | |
394 | } | |
395 | ||
ab5c9e90 ILT |
396 | // Return whether this dynamic symbol needs a special value in the |
397 | // dynamic symbol table. | |
398 | bool | |
399 | needs_dynsym_value() const | |
400 | { return this->needs_dynsym_value_; } | |
401 | ||
402 | // Set that this dynamic symbol needs a special value in the dynamic | |
403 | // symbol table. | |
404 | void | |
405 | set_needs_dynsym_value() | |
406 | { | |
407 | gold_assert(this->object()->is_dynamic()); | |
408 | this->needs_dynsym_value_ = true; | |
409 | } | |
410 | ||
a3ad94ed ILT |
411 | // Return true if the final value of this symbol is known at link |
412 | // time. | |
413 | bool | |
b3b74ddc | 414 | final_value_is_known() const; |
ead1e424 | 415 | |
f6ce93d6 ILT |
416 | // Return whether this is a defined symbol (not undefined or |
417 | // common). | |
418 | bool | |
419 | is_defined() const | |
420 | { | |
421 | return (this->source_ != FROM_OBJECT | |
16649710 ILT |
422 | || (this->shndx() != elfcpp::SHN_UNDEF |
423 | && this->shndx() != elfcpp::SHN_COMMON)); | |
a3ad94ed ILT |
424 | } |
425 | ||
14b31740 | 426 | // Return true if this symbol is from a dynamic object. |
a3ad94ed | 427 | bool |
14b31740 | 428 | is_from_dynobj() const |
a3ad94ed | 429 | { |
14b31740 | 430 | return this->source_ == FROM_OBJECT && this->object()->is_dynamic(); |
f6ce93d6 ILT |
431 | } |
432 | ||
ead1e424 ILT |
433 | // Return whether this is an undefined symbol. |
434 | bool | |
435 | is_undefined() const | |
436 | { | |
16649710 | 437 | return this->source_ == FROM_OBJECT && this->shndx() == elfcpp::SHN_UNDEF; |
ead1e424 ILT |
438 | } |
439 | ||
440 | // Return whether this is a common symbol. | |
441 | bool | |
442 | is_common() const | |
443 | { | |
f6ce93d6 | 444 | return (this->source_ == FROM_OBJECT |
16649710 | 445 | && (this->shndx() == elfcpp::SHN_COMMON |
f6ce93d6 | 446 | || this->type_ == elfcpp::STT_COMMON)); |
ead1e424 | 447 | } |
92e059d8 | 448 | |
a6badf5a ILT |
449 | // Return whether this symbol can be seen outside this object. |
450 | bool | |
451 | is_externally_visible() const | |
452 | { | |
453 | return (this->visibility_ == elfcpp::STV_DEFAULT | |
454 | || this->visibility_ == elfcpp::STV_PROTECTED); | |
455 | } | |
456 | ||
436ca963 ILT |
457 | // Return true if this symbol can be preempted by a definition in |
458 | // another link unit. | |
459 | bool | |
460 | is_preemptible() const | |
461 | { | |
386c048c ILT |
462 | // It doesn't make sense to ask whether a symbol defined in |
463 | // another object is preemptible. | |
464 | gold_assert(!this->is_from_dynobj()); | |
465 | ||
436ca963 ILT |
466 | return (this->visibility_ != elfcpp::STV_INTERNAL |
467 | && this->visibility_ != elfcpp::STV_HIDDEN | |
51b08ebe | 468 | && this->visibility_ != elfcpp::STV_PROTECTED |
d61c6bd4 | 469 | && parameters->output_is_shared() |
51b08ebe | 470 | && !parameters->symbolic()); |
436ca963 ILT |
471 | } |
472 | ||
d61c6bd4 ILT |
473 | // Return true if this symbol is a function that needs a PLT entry. |
474 | // If the symbol is defined in a dynamic object or if it is subject | |
475 | // to pre-emption, we need to make a PLT entry. | |
476 | bool | |
477 | needs_plt_entry() const | |
478 | { | |
479 | return (this->type() == elfcpp::STT_FUNC | |
480 | && (this->is_from_dynobj() || this->is_preemptible())); | |
481 | } | |
482 | ||
0700cf32 ILT |
483 | // When determining whether a reference to a symbol needs a dynamic |
484 | // relocation, we need to know several things about the reference. | |
485 | // These flags may be or'ed together. | |
486 | enum Reference_flags | |
487 | { | |
488 | // Reference to the symbol's absolute address. | |
489 | ABSOLUTE_REF = 1, | |
490 | // A non-PIC reference. | |
491 | NON_PIC_REF = 2, | |
492 | // A function call. | |
493 | FUNCTION_CALL = 4 | |
494 | }; | |
495 | ||
d61c6bd4 ILT |
496 | // Given a direct absolute or pc-relative static relocation against |
497 | // the global symbol, this function returns whether a dynamic relocation | |
498 | // is needed. | |
499 | ||
500 | bool | |
0700cf32 | 501 | needs_dynamic_reloc(int flags) const |
d61c6bd4 ILT |
502 | { |
503 | // An absolute reference within a position-independent output file | |
0700cf32 ILT |
504 | // will need a dynamic relocation. |
505 | if ((flags & ABSOLUTE_REF) | |
506 | && parameters->output_is_position_independent()) | |
d61c6bd4 ILT |
507 | return true; |
508 | ||
509 | // A function call that can branch to a local PLT entry does not need | |
510 | // a dynamic relocation. | |
0700cf32 ILT |
511 | if ((flags & FUNCTION_CALL) && this->has_plt_offset()) |
512 | return false; | |
513 | ||
514 | // A non-pic pc-relative function call in a shared library whose target | |
515 | // is defined in the same load module does not need a dynamic relocation. | |
516 | // Even if the target is preemptible, we will bind directly, since we | |
517 | // cannot use a PLT entry in this case. | |
518 | if ((flags & FUNCTION_CALL) | |
519 | && (flags & NON_PIC_REF) | |
520 | && this->is_defined() | |
521 | && parameters->output_is_shared()) | |
d61c6bd4 ILT |
522 | return false; |
523 | ||
524 | // A reference to any PLT entry in a non-position-independent executable | |
525 | // does not need a dynamic relocation. | |
526 | if (!parameters->output_is_position_independent() | |
527 | && this->has_plt_offset()) | |
528 | return false; | |
529 | ||
530 | // A reference to a symbol defined in a dynamic object or to a | |
531 | // symbol that is preemptible will need a dynamic relocation. | |
532 | if (this->is_from_dynobj() || this->is_preemptible()) | |
533 | return true; | |
534 | ||
535 | // For all other cases, return FALSE. | |
536 | return false; | |
537 | } | |
538 | ||
539 | // Given a direct absolute static relocation against | |
540 | // the global symbol, where a dynamic relocation is needed, this | |
541 | // function returns whether a relative dynamic relocation can be used. | |
542 | // The caller must determine separately whether the static relocation | |
543 | // is compatible with a relative relocation. | |
544 | ||
545 | bool | |
546 | can_use_relative_reloc(bool is_function_call) const | |
547 | { | |
548 | // A function call that can branch to a local PLT entry can | |
549 | // use a RELATIVE relocation. | |
550 | if (is_function_call && this->has_plt_offset()) | |
551 | return true; | |
552 | ||
553 | // A reference to a symbol defined in a dynamic object or to a | |
554 | // symbol that is preemptible can not use a RELATIVE relocaiton. | |
555 | if (this->is_from_dynobj() || this->is_preemptible()) | |
556 | return false; | |
557 | ||
558 | // For all other cases, return TRUE. | |
559 | return true; | |
560 | } | |
561 | ||
f6ce93d6 ILT |
562 | // Return whether there should be a warning for references to this |
563 | // symbol. | |
564 | bool | |
565 | has_warning() const | |
566 | { return this->has_warning_; } | |
567 | ||
568 | // Mark this symbol as having a warning. | |
569 | void | |
570 | set_has_warning() | |
571 | { this->has_warning_ = true; } | |
572 | ||
46fe1623 ILT |
573 | // Return whether this symbol is defined by a COPY reloc from a |
574 | // dynamic object. | |
575 | bool | |
576 | is_copied_from_dynobj() const | |
577 | { return this->is_copied_from_dynobj_; } | |
578 | ||
579 | // Mark this symbol as defined by a COPY reloc. | |
580 | void | |
581 | set_is_copied_from_dynobj() | |
582 | { this->is_copied_from_dynobj_ = true; } | |
583 | ||
14bfc3f5 ILT |
584 | protected: |
585 | // Instances of this class should always be created at a specific | |
586 | // size. | |
587 | Symbol() | |
f6ce93d6 | 588 | { memset(this, 0, sizeof *this); } |
14bfc3f5 | 589 | |
ead1e424 ILT |
590 | // Initialize the general fields. |
591 | void | |
592 | init_fields(const char* name, const char* version, | |
593 | elfcpp::STT type, elfcpp::STB binding, | |
594 | elfcpp::STV visibility, unsigned char nonvis); | |
595 | ||
14bfc3f5 ILT |
596 | // Initialize fields from an ELF symbol in OBJECT. |
597 | template<int size, bool big_endian> | |
598 | void | |
599 | init_base(const char *name, const char* version, Object* object, | |
600 | const elfcpp::Sym<size, big_endian>&); | |
bae7f79e | 601 | |
ead1e424 ILT |
602 | // Initialize fields for an Output_data. |
603 | void | |
604 | init_base(const char* name, Output_data*, elfcpp::STT, elfcpp::STB, | |
605 | elfcpp::STV, unsigned char nonvis, bool offset_is_from_end); | |
606 | ||
607 | // Initialize fields for an Output_segment. | |
608 | void | |
609 | init_base(const char* name, Output_segment* os, elfcpp::STT type, | |
610 | elfcpp::STB binding, elfcpp::STV visibility, | |
611 | unsigned char nonvis, Segment_offset_base offset_base); | |
612 | ||
613 | // Initialize fields for a constant. | |
614 | void | |
615 | init_base(const char* name, elfcpp::STT type, elfcpp::STB binding, | |
616 | elfcpp::STV visibility, unsigned char nonvis); | |
617 | ||
1564db8d ILT |
618 | // Override existing symbol. |
619 | template<int size, bool big_endian> | |
620 | void | |
14b31740 ILT |
621 | override_base(const elfcpp::Sym<size, big_endian>&, Object* object, |
622 | const char* version); | |
1564db8d | 623 | |
86f2e683 ILT |
624 | // Override existing symbol with a special symbol. |
625 | void | |
626 | override_base_with_special(const Symbol* from); | |
627 | ||
c7912668 ILT |
628 | // Allocate a common symbol by giving it a location in the output |
629 | // file. | |
630 | void | |
631 | allocate_base_common(Output_data*); | |
632 | ||
bae7f79e | 633 | private: |
14bfc3f5 ILT |
634 | Symbol(const Symbol&); |
635 | Symbol& operator=(const Symbol&); | |
636 | ||
637 | // Symbol name (expected to point into a Stringpool). | |
638 | const char* name_; | |
639 | // Symbol version (expected to point into a Stringpool). This may | |
640 | // be NULL. | |
bae7f79e | 641 | const char* version_; |
ead1e424 ILT |
642 | |
643 | union | |
644 | { | |
645 | // This struct is used if SOURCE_ == FROM_OBJECT. | |
646 | struct | |
647 | { | |
648 | // Object in which symbol is defined, or in which it was first | |
649 | // seen. | |
650 | Object* object; | |
651 | // Section number in object_ in which symbol is defined. | |
16649710 | 652 | unsigned int shndx; |
ead1e424 ILT |
653 | } from_object; |
654 | ||
655 | // This struct is used if SOURCE_ == IN_OUTPUT_DATA. | |
656 | struct | |
657 | { | |
658 | // Output_data in which symbol is defined. Before | |
659 | // Layout::finalize the symbol's value is an offset within the | |
660 | // Output_data. | |
661 | Output_data* output_data; | |
662 | // True if the offset is from the end, false if the offset is | |
663 | // from the beginning. | |
664 | bool offset_is_from_end; | |
665 | } in_output_data; | |
666 | ||
667 | // This struct is used if SOURCE_ == IN_OUTPUT_SEGMENT. | |
668 | struct | |
669 | { | |
670 | // Output_segment in which the symbol is defined. Before | |
671 | // Layout::finalize the symbol's value is an offset. | |
672 | Output_segment* output_segment; | |
673 | // The base to use for the offset before Layout::finalize. | |
674 | Segment_offset_base offset_base; | |
675 | } in_output_segment; | |
676 | } u_; | |
677 | ||
c06b7b0b ILT |
678 | // The index of this symbol in the output file. If the symbol is |
679 | // not going into the output file, this value is -1U. This field | |
680 | // starts as always holding zero. It is set to a non-zero value by | |
681 | // Symbol_table::finalize. | |
682 | unsigned int symtab_index_; | |
683 | ||
684 | // The index of this symbol in the dynamic symbol table. If the | |
685 | // symbol is not going into the dynamic symbol table, this value is | |
686 | // -1U. This field starts as always holding zero. It is set to a | |
687 | // non-zero value during Layout::finalize. | |
688 | unsigned int dynsym_index_; | |
689 | ||
ead1e424 | 690 | // If this symbol has an entry in the GOT section (has_got_offset_ |
c06b7b0b | 691 | // is true), this is the offset from the start of the GOT section. |
07f397ab ILT |
692 | // For a TLS symbol, if has_tls_tpoff_got_offset_ is true, this |
693 | // serves as the GOT offset for the GOT entry that holds its | |
694 | // TP-relative offset. | |
ead1e424 | 695 | unsigned int got_offset_; |
c06b7b0b | 696 | |
07f397ab ILT |
697 | // If this is a TLS symbol and has an entry in the GOT section |
698 | // for a module index or a pair of entries (module index, | |
699 | // dtv-relative offset), these are the offsets from the start | |
700 | // of the GOT section. | |
701 | unsigned int tls_mod_got_offset_; | |
702 | unsigned int tls_pair_got_offset_; | |
703 | ||
a3ad94ed ILT |
704 | // If this symbol has an entry in the PLT section (has_plt_offset_ |
705 | // is true), then this is the offset from the start of the PLT | |
706 | // section. | |
707 | unsigned int plt_offset_; | |
708 | ||
14bfc3f5 | 709 | // Symbol type. |
bae7f79e | 710 | elfcpp::STT type_ : 4; |
14bfc3f5 | 711 | // Symbol binding. |
bae7f79e | 712 | elfcpp::STB binding_ : 4; |
14bfc3f5 ILT |
713 | // Symbol visibility. |
714 | elfcpp::STV visibility_ : 2; | |
715 | // Rest of symbol st_other field. | |
ead1e424 ILT |
716 | unsigned int nonvis_ : 6; |
717 | // The type of symbol. | |
f6ce93d6 | 718 | Source source_ : 3; |
14bfc3f5 ILT |
719 | // True if this symbol always requires special target-specific |
720 | // handling. | |
ead1e424 | 721 | bool is_target_special_ : 1; |
14bfc3f5 | 722 | // True if this is the default version of the symbol. |
1564db8d | 723 | bool is_def_ : 1; |
14bfc3f5 ILT |
724 | // True if this symbol really forwards to another symbol. This is |
725 | // used when we discover after the fact that two different entries | |
726 | // in the hash table really refer to the same symbol. This will | |
727 | // never be set for a symbol found in the hash table, but may be set | |
728 | // for a symbol found in the list of symbols attached to an Object. | |
729 | // It forwards to the symbol found in the forwarders_ map of | |
730 | // Symbol_table. | |
1564db8d | 731 | bool is_forwarder_ : 1; |
aeddab66 ILT |
732 | // True if the symbol has an alias in the weak_aliases table in |
733 | // Symbol_table. | |
734 | bool has_alias_ : 1; | |
c06b7b0b ILT |
735 | // True if this symbol needs to be in the dynamic symbol table. |
736 | bool needs_dynsym_entry_ : 1; | |
008db82e ILT |
737 | // True if we've seen this symbol in a regular object. |
738 | bool in_reg_ : 1; | |
1564db8d ILT |
739 | // True if we've seen this symbol in a dynamic object. |
740 | bool in_dyn_ : 1; | |
ead1e424 | 741 | // True if the symbol has an entry in the GOT section. |
07f397ab | 742 | // For a TLS symbol, this GOT entry will hold its tp-relative offset. |
ead1e424 | 743 | bool has_got_offset_ : 1; |
07f397ab ILT |
744 | // True if the symbol has an entry in the GOT section for its |
745 | // module index. | |
746 | bool has_tls_mod_got_offset_ : 1; | |
747 | // True if the symbol has a pair of entries in the GOT section for its | |
748 | // module index and dtv-relative offset. | |
749 | bool has_tls_pair_got_offset_ : 1; | |
a3ad94ed ILT |
750 | // True if the symbol has an entry in the PLT section. |
751 | bool has_plt_offset_ : 1; | |
ab5c9e90 ILT |
752 | // True if this is a dynamic symbol which needs a special value in |
753 | // the dynamic symbol table. | |
754 | bool needs_dynsym_value_ : 1; | |
f6ce93d6 ILT |
755 | // True if there is a warning for this symbol. |
756 | bool has_warning_ : 1; | |
46fe1623 ILT |
757 | // True if we are using a COPY reloc for this symbol, so that the |
758 | // real definition lives in a dynamic object. | |
759 | bool is_copied_from_dynobj_ : 1; | |
bae7f79e ILT |
760 | }; |
761 | ||
14bfc3f5 ILT |
762 | // The parts of a symbol which are size specific. Using a template |
763 | // derived class like this helps us use less space on a 32-bit system. | |
bae7f79e ILT |
764 | |
765 | template<int size> | |
14bfc3f5 ILT |
766 | class Sized_symbol : public Symbol |
767 | { | |
768 | public: | |
1564db8d ILT |
769 | typedef typename elfcpp::Elf_types<size>::Elf_Addr Value_type; |
770 | typedef typename elfcpp::Elf_types<size>::Elf_WXword Size_type; | |
771 | ||
14bfc3f5 ILT |
772 | Sized_symbol() |
773 | { } | |
774 | ||
775 | // Initialize fields from an ELF symbol in OBJECT. | |
776 | template<bool big_endian> | |
777 | void | |
778 | init(const char *name, const char* version, Object* object, | |
779 | const elfcpp::Sym<size, big_endian>&); | |
780 | ||
ead1e424 ILT |
781 | // Initialize fields for an Output_data. |
782 | void | |
783 | init(const char* name, Output_data*, Value_type value, Size_type symsize, | |
784 | elfcpp::STT, elfcpp::STB, elfcpp::STV, unsigned char nonvis, | |
785 | bool offset_is_from_end); | |
786 | ||
787 | // Initialize fields for an Output_segment. | |
788 | void | |
789 | init(const char* name, Output_segment*, Value_type value, Size_type symsize, | |
790 | elfcpp::STT, elfcpp::STB, elfcpp::STV, unsigned char nonvis, | |
791 | Segment_offset_base offset_base); | |
792 | ||
793 | // Initialize fields for a constant. | |
794 | void | |
795 | init(const char* name, Value_type value, Size_type symsize, | |
796 | elfcpp::STT, elfcpp::STB, elfcpp::STV, unsigned char nonvis); | |
797 | ||
1564db8d ILT |
798 | // Override existing symbol. |
799 | template<bool big_endian> | |
800 | void | |
14b31740 ILT |
801 | override(const elfcpp::Sym<size, big_endian>&, Object* object, |
802 | const char* version); | |
1564db8d | 803 | |
86f2e683 ILT |
804 | // Override existing symbol with a special symbol. |
805 | void | |
806 | override_with_special(const Sized_symbol<size>*); | |
807 | ||
1564db8d ILT |
808 | // Return the symbol's value. |
809 | Value_type | |
810 | value() const | |
811 | { return this->value_; } | |
812 | ||
813 | // Return the symbol's size (we can't call this 'size' because that | |
814 | // is a template parameter). | |
815 | Size_type | |
816 | symsize() const | |
ead1e424 ILT |
817 | { return this->symsize_; } |
818 | ||
819 | // Set the symbol size. This is used when resolving common symbols. | |
820 | void | |
821 | set_symsize(Size_type symsize) | |
822 | { this->symsize_ = symsize; } | |
1564db8d | 823 | |
75f65a3e ILT |
824 | // Set the symbol value. This is called when we store the final |
825 | // values of the symbols into the symbol table. | |
826 | void | |
827 | set_value(Value_type value) | |
828 | { this->value_ = value; } | |
829 | ||
c7912668 ILT |
830 | // Allocate a common symbol by giving it a location in the output |
831 | // file. | |
832 | void | |
833 | allocate_common(Output_data*, Value_type value); | |
834 | ||
14bfc3f5 ILT |
835 | private: |
836 | Sized_symbol(const Sized_symbol&); | |
837 | Sized_symbol& operator=(const Sized_symbol&); | |
838 | ||
ead1e424 ILT |
839 | // Symbol value. Before Layout::finalize this is the offset in the |
840 | // input section. This is set to the final value during | |
841 | // Layout::finalize. | |
1564db8d | 842 | Value_type value_; |
14bfc3f5 | 843 | // Symbol size. |
ead1e424 ILT |
844 | Size_type symsize_; |
845 | }; | |
846 | ||
847 | // A struct describing a symbol defined by the linker, where the value | |
848 | // of the symbol is defined based on an output section. This is used | |
849 | // for symbols defined by the linker, like "_init_array_start". | |
850 | ||
851 | struct Define_symbol_in_section | |
852 | { | |
853 | // The symbol name. | |
854 | const char* name; | |
855 | // The name of the output section with which this symbol should be | |
856 | // associated. If there is no output section with that name, the | |
857 | // symbol will be defined as zero. | |
858 | const char* output_section; | |
859 | // The offset of the symbol within the output section. This is an | |
860 | // offset from the start of the output section, unless start_at_end | |
861 | // is true, in which case this is an offset from the end of the | |
862 | // output section. | |
863 | uint64_t value; | |
864 | // The size of the symbol. | |
865 | uint64_t size; | |
866 | // The symbol type. | |
867 | elfcpp::STT type; | |
868 | // The symbol binding. | |
869 | elfcpp::STB binding; | |
870 | // The symbol visibility. | |
871 | elfcpp::STV visibility; | |
872 | // The rest of the st_other field. | |
873 | unsigned char nonvis; | |
874 | // If true, the value field is an offset from the end of the output | |
875 | // section. | |
876 | bool offset_is_from_end; | |
877 | // If true, this symbol is defined only if we see a reference to it. | |
878 | bool only_if_ref; | |
879 | }; | |
880 | ||
881 | // A struct describing a symbol defined by the linker, where the value | |
882 | // of the symbol is defined based on a segment. This is used for | |
883 | // symbols defined by the linker, like "_end". We describe the | |
884 | // segment with which the symbol should be associated by its | |
885 | // characteristics. If no segment meets these characteristics, the | |
886 | // symbol will be defined as zero. If there is more than one segment | |
887 | // which meets these characteristics, we will use the first one. | |
888 | ||
889 | struct Define_symbol_in_segment | |
890 | { | |
891 | // The symbol name. | |
892 | const char* name; | |
893 | // The segment type where the symbol should be defined, typically | |
894 | // PT_LOAD. | |
895 | elfcpp::PT segment_type; | |
896 | // Bitmask of segment flags which must be set. | |
897 | elfcpp::PF segment_flags_set; | |
898 | // Bitmask of segment flags which must be clear. | |
899 | elfcpp::PF segment_flags_clear; | |
900 | // The offset of the symbol within the segment. The offset is | |
901 | // calculated from the position set by offset_base. | |
902 | uint64_t value; | |
903 | // The size of the symbol. | |
904 | uint64_t size; | |
905 | // The symbol type. | |
906 | elfcpp::STT type; | |
907 | // The symbol binding. | |
908 | elfcpp::STB binding; | |
909 | // The symbol visibility. | |
910 | elfcpp::STV visibility; | |
911 | // The rest of the st_other field. | |
912 | unsigned char nonvis; | |
913 | // The base from which we compute the offset. | |
914 | Symbol::Segment_offset_base offset_base; | |
915 | // If true, this symbol is defined only if we see a reference to it. | |
916 | bool only_if_ref; | |
14bfc3f5 ILT |
917 | }; |
918 | ||
f6ce93d6 ILT |
919 | // This class manages warnings. Warnings are a GNU extension. When |
920 | // we see a section named .gnu.warning.SYM in an object file, and if | |
921 | // we wind using the definition of SYM from that object file, then we | |
922 | // will issue a warning for any relocation against SYM from a | |
923 | // different object file. The text of the warning is the contents of | |
924 | // the section. This is not precisely the definition used by the old | |
925 | // GNU linker; the old GNU linker treated an occurrence of | |
926 | // .gnu.warning.SYM as defining a warning symbol. A warning symbol | |
927 | // would trigger a warning on any reference. However, it was | |
928 | // inconsistent in that a warning in a dynamic object only triggered | |
929 | // if there was no definition in a regular object. This linker is | |
930 | // different in that we only issue a warning if we use the symbol | |
931 | // definition from the same object file as the warning section. | |
932 | ||
933 | class Warnings | |
934 | { | |
935 | public: | |
936 | Warnings() | |
937 | : warnings_() | |
938 | { } | |
939 | ||
cb295612 ILT |
940 | // Add a warning for symbol NAME in object OBJ. WARNING is the text |
941 | // of the warning. | |
f6ce93d6 ILT |
942 | void |
943 | add_warning(Symbol_table* symtab, const char* name, Object* obj, | |
cb295612 | 944 | const std::string& warning); |
f6ce93d6 ILT |
945 | |
946 | // For each symbol for which we should give a warning, make a note | |
947 | // on the symbol. | |
948 | void | |
cb295612 | 949 | note_warnings(Symbol_table* symtab); |
f6ce93d6 | 950 | |
75f2446e ILT |
951 | // Issue a warning for a reference to SYM at RELINFO's location. |
952 | template<int size, bool big_endian> | |
f6ce93d6 | 953 | void |
75f2446e ILT |
954 | issue_warning(const Symbol* sym, const Relocate_info<size, big_endian>*, |
955 | size_t relnum, off_t reloffset) const; | |
f6ce93d6 ILT |
956 | |
957 | private: | |
958 | Warnings(const Warnings&); | |
959 | Warnings& operator=(const Warnings&); | |
960 | ||
961 | // What we need to know to get the warning text. | |
962 | struct Warning_location | |
963 | { | |
964 | // The object the warning is in. | |
965 | Object* object; | |
cb295612 | 966 | // The warning text. |
f6ce93d6 ILT |
967 | std::string text; |
968 | ||
969 | Warning_location() | |
cb295612 | 970 | : object(NULL), text() |
f6ce93d6 ILT |
971 | { } |
972 | ||
973 | void | |
cb295612 | 974 | set(Object* o, const std::string& t) |
f6ce93d6 ILT |
975 | { |
976 | this->object = o; | |
cb295612 | 977 | this->text = t; |
f6ce93d6 | 978 | } |
f6ce93d6 ILT |
979 | }; |
980 | ||
981 | // A mapping from warning symbol names (canonicalized in | |
70e654ba | 982 | // Symbol_table's namepool_ field) to warning information. |
f6ce93d6 ILT |
983 | typedef Unordered_map<const char*, Warning_location> Warning_table; |
984 | ||
985 | Warning_table warnings_; | |
986 | }; | |
987 | ||
14bfc3f5 ILT |
988 | // The main linker symbol table. |
989 | ||
bae7f79e ILT |
990 | class Symbol_table |
991 | { | |
992 | public: | |
6d013333 ILT |
993 | // COUNT is an estimate of how many symbosl will be inserted in the |
994 | // symbol table. It's ok to put 0 if you don't know; a correct | |
995 | // guess will just save some CPU by reducing hashtable resizes. | |
09124467 | 996 | Symbol_table(unsigned int count, const Version_script_info& version_script); |
bae7f79e | 997 | |
1564db8d | 998 | ~Symbol_table(); |
bae7f79e | 999 | |
dbe717ef | 1000 | // Add COUNT external symbols from the relocatable object RELOBJ to |
f6ce93d6 ILT |
1001 | // the symbol table. SYMS is the symbols, SYM_NAMES is their names, |
1002 | // SYM_NAME_SIZE is the size of SYM_NAMES. This sets SYMPOINTERS to | |
1003 | // point to the symbols in the symbol table. | |
14bfc3f5 ILT |
1004 | template<int size, bool big_endian> |
1005 | void | |
dbe717ef ILT |
1006 | add_from_relobj(Sized_relobj<size, big_endian>* relobj, |
1007 | const unsigned char* syms, size_t count, | |
1008 | const char* sym_names, size_t sym_name_size, | |
730cdc88 | 1009 | typename Sized_relobj<size, big_endian>::Symbols*); |
14bfc3f5 | 1010 | |
dbe717ef ILT |
1011 | // Add COUNT dynamic symbols from the dynamic object DYNOBJ to the |
1012 | // symbol table. SYMS is the symbols. SYM_NAMES is their names. | |
1013 | // SYM_NAME_SIZE is the size of SYM_NAMES. The other parameters are | |
1014 | // symbol version data. | |
1015 | template<int size, bool big_endian> | |
1016 | void | |
1017 | add_from_dynobj(Sized_dynobj<size, big_endian>* dynobj, | |
1018 | const unsigned char* syms, size_t count, | |
1019 | const char* sym_names, size_t sym_name_size, | |
1020 | const unsigned char* versym, size_t versym_size, | |
1021 | const std::vector<const char*>*); | |
1022 | ||
ead1e424 ILT |
1023 | // Define a special symbol based on an Output_data. It is a |
1024 | // multiple definition error if this symbol is already defined. | |
14b31740 ILT |
1025 | Symbol* |
1026 | define_in_output_data(const Target*, const char* name, const char* version, | |
1027 | Output_data*, uint64_t value, uint64_t symsize, | |
ead1e424 ILT |
1028 | elfcpp::STT type, elfcpp::STB binding, |
1029 | elfcpp::STV visibility, unsigned char nonvis, | |
1030 | bool offset_is_from_end, bool only_if_ref); | |
1031 | ||
1032 | // Define a special symbol based on an Output_segment. It is a | |
1033 | // multiple definition error if this symbol is already defined. | |
14b31740 ILT |
1034 | Symbol* |
1035 | define_in_output_segment(const Target*, const char* name, | |
1036 | const char* version, Output_segment*, | |
ead1e424 ILT |
1037 | uint64_t value, uint64_t symsize, |
1038 | elfcpp::STT type, elfcpp::STB binding, | |
1039 | elfcpp::STV visibility, unsigned char nonvis, | |
1040 | Symbol::Segment_offset_base, bool only_if_ref); | |
1041 | ||
1042 | // Define a special symbol with a constant value. It is a multiple | |
1043 | // definition error if this symbol is already defined. | |
14b31740 ILT |
1044 | Symbol* |
1045 | define_as_constant(const Target*, const char* name, const char* version, | |
1046 | uint64_t value, uint64_t symsize, elfcpp::STT type, | |
1047 | elfcpp::STB binding, elfcpp::STV visibility, | |
1048 | unsigned char nonvis, bool only_if_ref); | |
ead1e424 ILT |
1049 | |
1050 | // Define a set of symbols in output sections. | |
1051 | void | |
14b31740 | 1052 | define_symbols(const Layout*, const Target*, int count, |
ead1e424 ILT |
1053 | const Define_symbol_in_section*); |
1054 | ||
1055 | // Define a set of symbols in output segments. | |
1056 | void | |
14b31740 | 1057 | define_symbols(const Layout*, const Target*, int count, |
70e654ba | 1058 | const Define_symbol_in_segment*); |
ead1e424 | 1059 | |
46fe1623 ILT |
1060 | // Define SYM using a COPY reloc. POSD is the Output_data where the |
1061 | // symbol should be defined--typically a .dyn.bss section. VALUE is | |
1062 | // the offset within POSD. | |
1063 | template<int size> | |
1064 | void | |
1065 | define_with_copy_reloc(const Target*, Sized_symbol<size>* sym, | |
fe8718a4 ILT |
1066 | Output_data* posd, |
1067 | typename elfcpp::Elf_types<size>::Elf_Addr); | |
46fe1623 | 1068 | |
61ba1cf9 ILT |
1069 | // Look up a symbol. |
1070 | Symbol* | |
1071 | lookup(const char*, const char* version = NULL) const; | |
1072 | ||
14bfc3f5 | 1073 | // Return the real symbol associated with the forwarder symbol FROM. |
bae7f79e | 1074 | Symbol* |
c06b7b0b | 1075 | resolve_forwards(const Symbol* from) const; |
bae7f79e | 1076 | |
1564db8d ILT |
1077 | // Return the sized version of a symbol in this table. |
1078 | template<int size> | |
1079 | Sized_symbol<size>* | |
5482377d | 1080 | get_sized_symbol(Symbol* ACCEPT_SIZE) const; |
1564db8d ILT |
1081 | |
1082 | template<int size> | |
1083 | const Sized_symbol<size>* | |
5482377d | 1084 | get_sized_symbol(const Symbol* ACCEPT_SIZE) const; |
54dc6425 | 1085 | |
ead1e424 ILT |
1086 | // Return the count of undefined symbols seen. |
1087 | int | |
1088 | saw_undefined() const | |
1089 | { return this->saw_undefined_; } | |
1090 | ||
1091 | // Allocate the common symbols | |
1092 | void | |
1093 | allocate_commons(const General_options&, Layout*); | |
1094 | ||
cb295612 ILT |
1095 | // Add a warning for symbol NAME in object OBJ. WARNING is the text |
1096 | // of the warning. | |
f6ce93d6 | 1097 | void |
cb295612 ILT |
1098 | add_warning(const char* name, Object* obj, const std::string& warning) |
1099 | { this->warnings_.add_warning(this, name, obj, warning); } | |
f6ce93d6 ILT |
1100 | |
1101 | // Canonicalize a symbol name for use in the hash table. | |
1102 | const char* | |
1103 | canonicalize_name(const char* name) | |
cfd73a4e | 1104 | { return this->namepool_.add(name, true, NULL); } |
f6ce93d6 ILT |
1105 | |
1106 | // Possibly issue a warning for a reference to SYM at LOCATION which | |
1107 | // is in OBJ. | |
75f2446e | 1108 | template<int size, bool big_endian> |
f6ce93d6 | 1109 | void |
75f2446e ILT |
1110 | issue_warning(const Symbol* sym, |
1111 | const Relocate_info<size, big_endian>* relinfo, | |
1112 | size_t relnum, off_t reloffset) const | |
1113 | { this->warnings_.issue_warning(sym, relinfo, relnum, reloffset); } | |
f6ce93d6 | 1114 | |
70e654ba ILT |
1115 | // Check candidate_odr_violations_ to find symbols with the same name |
1116 | // but apparently different definitions (different source-file/line-no). | |
1117 | void | |
17a1d0a9 | 1118 | detect_odr_violations(const Task*, const char* output_file_name) const; |
70e654ba | 1119 | |
46fe1623 ILT |
1120 | // SYM is defined using a COPY reloc. Return the dynamic object |
1121 | // where the original definition was found. | |
1122 | Dynobj* | |
1123 | get_copy_source(const Symbol* sym) const; | |
1124 | ||
a3ad94ed ILT |
1125 | // Set the dynamic symbol indexes. INDEX is the index of the first |
1126 | // global dynamic symbol. Pointers to the symbols are stored into | |
1127 | // the vector. The names are stored into the Stringpool. This | |
1128 | // returns an updated dynamic symbol index. | |
1129 | unsigned int | |
35cdfc9a | 1130 | set_dynsym_indexes(const Target*, unsigned int index, |
14b31740 | 1131 | std::vector<Symbol*>*, Stringpool*, Versions*); |
a3ad94ed | 1132 | |
75f65a3e | 1133 | // Finalize the symbol table after we have set the final addresses |
c06b7b0b ILT |
1134 | // of all the input sections. This sets the final symbol indexes, |
1135 | // values and adds the names to *POOL. INDEX is the index of the | |
16649710 ILT |
1136 | // first global symbol. OFF is the file offset of the global symbol |
1137 | // table, DYNOFF is the offset of the globals in the dynamic symbol | |
1138 | // table, DYN_GLOBAL_INDEX is the index of the first global dynamic | |
1139 | // symbol, and DYNCOUNT is the number of global dynamic symbols. | |
1140 | // This records the parameters, and returns the new file offset. | |
75f65a3e | 1141 | off_t |
cb295612 | 1142 | finalize(unsigned int index, off_t off, off_t dynoff, |
16649710 | 1143 | size_t dyn_global_index, size_t dyncount, Stringpool* pool); |
1564db8d | 1144 | |
61ba1cf9 ILT |
1145 | // Write out the global symbols. |
1146 | void | |
9a2d6984 | 1147 | write_globals(const Input_objects*, const Stringpool*, const Stringpool*, |
16649710 | 1148 | Output_file*) const; |
61ba1cf9 | 1149 | |
a3ad94ed ILT |
1150 | // Write out a section symbol. Return the updated offset. |
1151 | void | |
9025d29d | 1152 | write_section_symbol(const Output_section*, Output_file*, off_t) const; |
a3ad94ed | 1153 | |
abaa3995 ILT |
1154 | // Dump statistical information to stderr. |
1155 | void | |
1156 | print_stats() const; | |
1157 | ||
09124467 ILT |
1158 | // Return the version script information. |
1159 | const Version_script_info& | |
1160 | version_script() const | |
1161 | { return version_script_; } | |
1162 | ||
bae7f79e ILT |
1163 | private: |
1164 | Symbol_table(const Symbol_table&); | |
1165 | Symbol_table& operator=(const Symbol_table&); | |
1166 | ||
14bfc3f5 ILT |
1167 | // Make FROM a forwarder symbol to TO. |
1168 | void | |
1169 | make_forwarder(Symbol* from, Symbol* to); | |
1170 | ||
1171 | // Add a symbol. | |
1172 | template<int size, bool big_endian> | |
aeddab66 | 1173 | Sized_symbol<size>* |
f0641a0b ILT |
1174 | add_from_object(Object*, const char *name, Stringpool::Key name_key, |
1175 | const char *version, Stringpool::Key version_key, | |
70e654ba ILT |
1176 | bool def, const elfcpp::Sym<size, big_endian>& sym, |
1177 | const elfcpp::Sym<size, big_endian>& orig_sym); | |
14bfc3f5 ILT |
1178 | |
1179 | // Resolve symbols. | |
1180 | template<int size, bool big_endian> | |
aeddab66 | 1181 | void |
1564db8d ILT |
1182 | resolve(Sized_symbol<size>* to, |
1183 | const elfcpp::Sym<size, big_endian>& sym, | |
70e654ba | 1184 | const elfcpp::Sym<size, big_endian>& orig_sym, |
14b31740 | 1185 | Object*, const char* version); |
14bfc3f5 | 1186 | |
1564db8d | 1187 | template<int size, bool big_endian> |
aeddab66 | 1188 | void |
14b31740 ILT |
1189 | resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from, |
1190 | const char* version ACCEPT_SIZE_ENDIAN); | |
1191 | ||
86f2e683 ILT |
1192 | // Whether we should override a symbol, based on flags in |
1193 | // resolve.cc. | |
1194 | static bool | |
d20222a1 | 1195 | should_override(const Symbol*, unsigned int, Object*, bool*); |
86f2e683 | 1196 | |
aeddab66 ILT |
1197 | // Override a symbol. |
1198 | template<int size, bool big_endian> | |
1199 | void | |
1200 | override(Sized_symbol<size>* tosym, | |
1201 | const elfcpp::Sym<size, big_endian>& fromsym, | |
1202 | Object* object, const char* version); | |
1203 | ||
86f2e683 ILT |
1204 | // Whether we should override a symbol with a special symbol which |
1205 | // is automatically defined by the linker. | |
1206 | static bool | |
1207 | should_override_with_special(const Symbol*); | |
1208 | ||
aeddab66 ILT |
1209 | // Override a symbol with a special symbol. |
1210 | template<int size> | |
1211 | void | |
1212 | override_with_special(Sized_symbol<size>* tosym, | |
1213 | const Sized_symbol<size>* fromsym); | |
1214 | ||
1215 | // Record all weak alias sets for a dynamic object. | |
1216 | template<int size> | |
1217 | void | |
1218 | record_weak_aliases(std::vector<Sized_symbol<size>*>*); | |
1219 | ||
14b31740 ILT |
1220 | // Define a special symbol. |
1221 | template<int size, bool big_endian> | |
1222 | Sized_symbol<size>* | |
306d9ef0 ILT |
1223 | define_special_symbol(const Target* target, const char** pname, |
1224 | const char** pversion, bool only_if_ref, | |
86f2e683 | 1225 | Sized_symbol<size>** poldsym ACCEPT_SIZE_ENDIAN); |
14bfc3f5 | 1226 | |
ead1e424 ILT |
1227 | // Define a symbol in an Output_data, sized version. |
1228 | template<int size> | |
14b31740 ILT |
1229 | Sized_symbol<size>* |
1230 | do_define_in_output_data(const Target*, const char* name, | |
1231 | const char* version, Output_data*, | |
ead1e424 ILT |
1232 | typename elfcpp::Elf_types<size>::Elf_Addr value, |
1233 | typename elfcpp::Elf_types<size>::Elf_WXword ssize, | |
1234 | elfcpp::STT type, elfcpp::STB binding, | |
1235 | elfcpp::STV visibility, unsigned char nonvis, | |
1236 | bool offset_is_from_end, bool only_if_ref); | |
1237 | ||
1238 | // Define a symbol in an Output_segment, sized version. | |
1239 | template<int size> | |
14b31740 | 1240 | Sized_symbol<size>* |
ead1e424 | 1241 | do_define_in_output_segment( |
14b31740 | 1242 | const Target*, const char* name, const char* version, Output_segment* os, |
ead1e424 ILT |
1243 | typename elfcpp::Elf_types<size>::Elf_Addr value, |
1244 | typename elfcpp::Elf_types<size>::Elf_WXword ssize, | |
1245 | elfcpp::STT type, elfcpp::STB binding, | |
1246 | elfcpp::STV visibility, unsigned char nonvis, | |
1247 | Symbol::Segment_offset_base offset_base, bool only_if_ref); | |
1248 | ||
1249 | // Define a symbol as a constant, sized version. | |
1250 | template<int size> | |
14b31740 | 1251 | Sized_symbol<size>* |
ead1e424 | 1252 | do_define_as_constant( |
14b31740 | 1253 | const Target*, const char* name, const char* version, |
ead1e424 ILT |
1254 | typename elfcpp::Elf_types<size>::Elf_Addr value, |
1255 | typename elfcpp::Elf_types<size>::Elf_WXword ssize, | |
1256 | elfcpp::STT type, elfcpp::STB binding, | |
1257 | elfcpp::STV visibility, unsigned char nonvis, | |
1258 | bool only_if_ref); | |
1259 | ||
1260 | // Allocate the common symbols, sized version. | |
1261 | template<int size> | |
1262 | void | |
1263 | do_allocate_commons(const General_options&, Layout*); | |
1264 | ||
70e654ba ILT |
1265 | // Implement detect_odr_violations. |
1266 | template<int size, bool big_endian> | |
1267 | void | |
1268 | sized_detect_odr_violations() const; | |
1269 | ||
75f65a3e ILT |
1270 | // Finalize symbols specialized for size. |
1271 | template<int size> | |
1272 | off_t | |
c06b7b0b | 1273 | sized_finalize(unsigned int, off_t, Stringpool*); |
75f65a3e | 1274 | |
61ba1cf9 ILT |
1275 | // Write globals specialized for size and endianness. |
1276 | template<int size, bool big_endian> | |
1277 | void | |
9a2d6984 ILT |
1278 | sized_write_globals(const Input_objects*, const Stringpool*, |
1279 | const Stringpool*, Output_file*) const; | |
16649710 ILT |
1280 | |
1281 | // Write out a symbol to P. | |
1282 | template<int size, bool big_endian> | |
1283 | void | |
ab5c9e90 ILT |
1284 | sized_write_symbol(Sized_symbol<size>*, |
1285 | typename elfcpp::Elf_types<size>::Elf_Addr value, | |
1286 | unsigned int shndx, | |
6a469986 ILT |
1287 | const Stringpool*, unsigned char* p |
1288 | ACCEPT_SIZE_ENDIAN) const; | |
61ba1cf9 | 1289 | |
9a2d6984 ILT |
1290 | // Possibly warn about an undefined symbol from a dynamic object. |
1291 | void | |
1292 | warn_about_undefined_dynobj_symbol(const Input_objects*, Symbol*) const; | |
1293 | ||
a3ad94ed ILT |
1294 | // Write out a section symbol, specialized for size and endianness. |
1295 | template<int size, bool big_endian> | |
1296 | void | |
1297 | sized_write_section_symbol(const Output_section*, Output_file*, off_t) const; | |
1298 | ||
54dc6425 ILT |
1299 | // The type of the symbol hash table. |
1300 | ||
f0641a0b | 1301 | typedef std::pair<Stringpool::Key, Stringpool::Key> Symbol_table_key; |
14bfc3f5 ILT |
1302 | |
1303 | struct Symbol_table_hash | |
1304 | { | |
1305 | size_t | |
1306 | operator()(const Symbol_table_key&) const; | |
1307 | }; | |
1308 | ||
1309 | struct Symbol_table_eq | |
1310 | { | |
1311 | bool | |
1312 | operator()(const Symbol_table_key&, const Symbol_table_key&) const; | |
1313 | }; | |
1314 | ||
1315 | typedef Unordered_map<Symbol_table_key, Symbol*, Symbol_table_hash, | |
1316 | Symbol_table_eq> Symbol_table_type; | |
1317 | ||
ead1e424 | 1318 | // The type of the list of common symbols. |
ead1e424 ILT |
1319 | typedef std::vector<Symbol*> Commons_type; |
1320 | ||
46fe1623 ILT |
1321 | // A map from symbols with COPY relocs to the dynamic objects where |
1322 | // they are defined. | |
1323 | typedef Unordered_map<const Symbol*, Dynobj*> Copied_symbol_dynobjs; | |
1324 | ||
70e654ba ILT |
1325 | // A map from symbol name (as a pointer into the namepool) to all |
1326 | // the locations the symbols is (weakly) defined (and certain other | |
1327 | // conditions are met). This map will be used later to detect | |
1328 | // possible One Definition Rule (ODR) violations. | |
1329 | struct Symbol_location | |
1330 | { | |
1331 | Object* object; // Object where the symbol is defined. | |
1332 | unsigned int shndx; // Section-in-object where the symbol is defined. | |
1333 | off_t offset; // Offset-in-section where the symbol is defined. | |
1334 | bool operator==(const Symbol_location& that) const | |
1335 | { | |
1336 | return (this->object == that.object | |
1337 | && this->shndx == that.shndx | |
1338 | && this->offset == that.offset); | |
1339 | } | |
1340 | }; | |
1341 | ||
1342 | struct Symbol_location_hash | |
1343 | { | |
1344 | size_t operator()(const Symbol_location& loc) const | |
1345 | { return reinterpret_cast<uintptr_t>(loc.object) ^ loc.offset ^ loc.shndx; } | |
1346 | }; | |
1347 | ||
1348 | typedef Unordered_map<const char*, | |
1349 | Unordered_set<Symbol_location, Symbol_location_hash> > | |
1350 | Odr_map; | |
1351 | ||
ead1e424 ILT |
1352 | // We increment this every time we see a new undefined symbol, for |
1353 | // use in archive groups. | |
1354 | int saw_undefined_; | |
c06b7b0b ILT |
1355 | // The index of the first global symbol in the output file. |
1356 | unsigned int first_global_index_; | |
75f65a3e ILT |
1357 | // The file offset within the output symtab section where we should |
1358 | // write the table. | |
1359 | off_t offset_; | |
61ba1cf9 ILT |
1360 | // The number of global symbols we want to write out. |
1361 | size_t output_count_; | |
16649710 ILT |
1362 | // The file offset of the global dynamic symbols, or 0 if none. |
1363 | off_t dynamic_offset_; | |
16649710 ILT |
1364 | // The index of the first global dynamic symbol. |
1365 | unsigned int first_dynamic_global_index_; | |
16649710 ILT |
1366 | // The number of global dynamic symbols, or 0 if none. |
1367 | off_t dynamic_count_; | |
54dc6425 | 1368 | // The symbol hash table. |
14bfc3f5 | 1369 | Symbol_table_type table_; |
54dc6425 ILT |
1370 | // A pool of symbol names. This is used for all global symbols. |
1371 | // Entries in the hash table point into this pool. | |
14bfc3f5 | 1372 | Stringpool namepool_; |
14bfc3f5 | 1373 | // Forwarding symbols. |
c06b7b0b | 1374 | Unordered_map<const Symbol*, Symbol*> forwarders_; |
aeddab66 ILT |
1375 | // Weak aliases. A symbol in this list points to the next alias. |
1376 | // The aliases point to each other in a circular list. | |
1377 | Unordered_map<Symbol*, Symbol*> weak_aliases_; | |
ead1e424 ILT |
1378 | // We don't expect there to be very many common symbols, so we keep |
1379 | // a list of them. When we find a common symbol we add it to this | |
1380 | // list. It is possible that by the time we process the list the | |
1381 | // symbol is no longer a common symbol. It may also have become a | |
1382 | // forwarder. | |
1383 | Commons_type commons_; | |
f6ce93d6 ILT |
1384 | // Manage symbol warnings. |
1385 | Warnings warnings_; | |
70e654ba ILT |
1386 | // Manage potential One Definition Rule (ODR) violations. |
1387 | Odr_map candidate_odr_violations_; | |
1388 | ||
46fe1623 ILT |
1389 | // When we emit a COPY reloc for a symbol, we define it in an |
1390 | // Output_data. When it's time to emit version information for it, | |
1391 | // we need to know the dynamic object in which we found the original | |
1392 | // definition. This maps symbols with COPY relocs to the dynamic | |
1393 | // object where they were defined. | |
1394 | Copied_symbol_dynobjs copied_symbol_dynobjs_; | |
09124467 ILT |
1395 | // Information parsed from the version script, if any. |
1396 | const Version_script_info& version_script_; | |
bae7f79e ILT |
1397 | }; |
1398 | ||
1564db8d ILT |
1399 | // We inline get_sized_symbol for efficiency. |
1400 | ||
1401 | template<int size> | |
1402 | Sized_symbol<size>* | |
5482377d | 1403 | Symbol_table::get_sized_symbol(Symbol* sym ACCEPT_SIZE) const |
1564db8d | 1404 | { |
9025d29d | 1405 | gold_assert(size == parameters->get_size()); |
1564db8d ILT |
1406 | return static_cast<Sized_symbol<size>*>(sym); |
1407 | } | |
1408 | ||
1409 | template<int size> | |
1410 | const Sized_symbol<size>* | |
5482377d | 1411 | Symbol_table::get_sized_symbol(const Symbol* sym ACCEPT_SIZE) const |
1564db8d | 1412 | { |
9025d29d | 1413 | gold_assert(size == parameters->get_size()); |
1564db8d ILT |
1414 | return static_cast<const Sized_symbol<size>*>(sym); |
1415 | } | |
1416 | ||
bae7f79e ILT |
1417 | } // End namespace gold. |
1418 | ||
1419 | #endif // !defined(GOLD_SYMTAB_H) |