Remove path name from test case
[binutils-gdb.git] / gdb / minsyms.c
1 /* GDB routines for manipulating the minimal symbol tables.
2 Copyright (C) 1992-2023 Free Software Foundation, Inc.
3 Contributed by Cygnus Support, using pieces from other GDB modules.
4
5 This file is part of GDB.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19
20
21 /* This file contains support routines for creating, manipulating, and
22 destroying minimal symbol tables.
23
24 Minimal symbol tables are used to hold some very basic information about
25 all defined global symbols (text, data, bss, abs, etc). The only two
26 required pieces of information are the symbol's name and the address
27 associated with that symbol.
28
29 In many cases, even if a file was compiled with no special options for
30 debugging at all, as long as was not stripped it will contain sufficient
31 information to build useful minimal symbol tables using this structure.
32
33 Even when a file contains enough debugging information to build a full
34 symbol table, these minimal symbols are still useful for quickly mapping
35 between names and addresses, and vice versa. They are also sometimes used
36 to figure out what full symbol table entries need to be read in. */
37
38
39 #include "defs.h"
40 #include <ctype.h>
41 #include "symtab.h"
42 #include "bfd.h"
43 #include "filenames.h"
44 #include "symfile.h"
45 #include "objfiles.h"
46 #include "demangle.h"
47 #include "value.h"
48 #include "cp-abi.h"
49 #include "target.h"
50 #include "cp-support.h"
51 #include "language.h"
52 #include "cli/cli-utils.h"
53 #include "gdbsupport/symbol.h"
54 #include <algorithm>
55 #include "gdbsupport/gdb-safe-ctype.h"
56 #include "gdbsupport/parallel-for.h"
57 #include "inferior.h"
58
59 #if CXX_STD_THREAD
60 #include <mutex>
61 #endif
62
63 /* Return true if MINSYM is a cold clone symbol.
64 Recognize f.i. these symbols (mangled/demangled):
65 - _ZL3foov.cold
66 foo() [clone .cold]
67 - _ZL9do_rpo_vnP8functionP8edge_defP11bitmap_headbb.cold.138
68 do_rpo_vn(function*, edge_def*, bitmap_head*, bool, bool) \
69 [clone .cold.138]. */
70
71 static bool
72 msymbol_is_cold_clone (minimal_symbol *minsym)
73 {
74 const char *name = minsym->natural_name ();
75 size_t name_len = strlen (name);
76 if (name_len < 1)
77 return false;
78
79 const char *last = &name[name_len - 1];
80 if (*last != ']')
81 return false;
82
83 const char *suffix = " [clone .cold";
84 size_t suffix_len = strlen (suffix);
85 const char *found = strstr (name, suffix);
86 if (found == nullptr)
87 return false;
88
89 const char *start = &found[suffix_len];
90 if (*start == ']')
91 return true;
92
93 if (*start != '.')
94 return false;
95
96 const char *p;
97 for (p = start + 1; p <= last; ++p)
98 {
99 if (*p >= '0' && *p <= '9')
100 continue;
101 break;
102 }
103
104 if (p == last)
105 return true;
106
107 return false;
108 }
109
110 /* See minsyms.h. */
111
112 bool
113 msymbol_is_function (struct objfile *objfile, minimal_symbol *minsym,
114 CORE_ADDR *func_address_p)
115 {
116 CORE_ADDR msym_addr = minsym->value_address (objfile);
117
118 switch (minsym->type ())
119 {
120 case mst_slot_got_plt:
121 case mst_data:
122 case mst_bss:
123 case mst_abs:
124 case mst_file_data:
125 case mst_file_bss:
126 case mst_data_gnu_ifunc:
127 {
128 struct gdbarch *gdbarch = objfile->arch ();
129 CORE_ADDR pc = gdbarch_convert_from_func_ptr_addr
130 (gdbarch, msym_addr, current_inferior ()->top_target ());
131 if (pc != msym_addr)
132 {
133 if (func_address_p != NULL)
134 *func_address_p = pc;
135 return true;
136 }
137 return false;
138 }
139 case mst_file_text:
140 /* Ignore function symbol that is not a function entry. */
141 if (msymbol_is_cold_clone (minsym))
142 return false;
143 /* fallthru */
144 default:
145 if (func_address_p != NULL)
146 *func_address_p = msym_addr;
147 return true;
148 }
149 }
150
151 /* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE.
152 At the end, copy them all into one newly allocated array. */
153
154 #define BUNCH_SIZE 127
155
156 struct msym_bunch
157 {
158 struct msym_bunch *next;
159 struct minimal_symbol contents[BUNCH_SIZE];
160 };
161
162 /* See minsyms.h. */
163
164 unsigned int
165 msymbol_hash_iw (const char *string)
166 {
167 unsigned int hash = 0;
168
169 while (*string && *string != '(')
170 {
171 string = skip_spaces (string);
172 if (*string && *string != '(')
173 {
174 hash = SYMBOL_HASH_NEXT (hash, *string);
175 ++string;
176 }
177 }
178 return hash;
179 }
180
181 /* See minsyms.h. */
182
183 unsigned int
184 msymbol_hash (const char *string)
185 {
186 unsigned int hash = 0;
187
188 for (; *string; ++string)
189 hash = SYMBOL_HASH_NEXT (hash, *string);
190 return hash;
191 }
192
193 /* Add the minimal symbol SYM to an objfile's minsym hash table, TABLE. */
194 static void
195 add_minsym_to_hash_table (struct minimal_symbol *sym,
196 struct minimal_symbol **table,
197 unsigned int hash_value)
198 {
199 if (sym->hash_next == NULL)
200 {
201 unsigned int hash = hash_value % MINIMAL_SYMBOL_HASH_SIZE;
202
203 sym->hash_next = table[hash];
204 table[hash] = sym;
205 }
206 }
207
208 /* Add the minimal symbol SYM to an objfile's minsym demangled hash table,
209 TABLE. */
210 static void
211 add_minsym_to_demangled_hash_table (struct minimal_symbol *sym,
212 struct objfile *objfile,
213 unsigned int hash_value)
214 {
215 if (sym->demangled_hash_next == NULL)
216 {
217 objfile->per_bfd->demangled_hash_languages.set (sym->language ());
218
219 struct minimal_symbol **table
220 = objfile->per_bfd->msymbol_demangled_hash;
221 unsigned int hash_index = hash_value % MINIMAL_SYMBOL_HASH_SIZE;
222 sym->demangled_hash_next = table[hash_index];
223 table[hash_index] = sym;
224 }
225 }
226
227 /* Worker object for lookup_minimal_symbol. Stores temporary results
228 while walking the symbol tables. */
229
230 struct found_minimal_symbols
231 {
232 /* External symbols are best. */
233 bound_minimal_symbol external_symbol;
234
235 /* File-local symbols are next best. */
236 bound_minimal_symbol file_symbol;
237
238 /* Symbols for shared library trampolines are next best. */
239 bound_minimal_symbol trampoline_symbol;
240
241 /* Called when a symbol name matches. Check if the minsym is a
242 better type than what we had already found, and record it in one
243 of the members fields if so. Returns true if we collected the
244 real symbol, in which case we can stop searching. */
245 bool maybe_collect (const char *sfile, objfile *objf,
246 minimal_symbol *msymbol);
247 };
248
249 /* See declaration above. */
250
251 bool
252 found_minimal_symbols::maybe_collect (const char *sfile,
253 struct objfile *objfile,
254 minimal_symbol *msymbol)
255 {
256 switch (msymbol->type ())
257 {
258 case mst_file_text:
259 case mst_file_data:
260 case mst_file_bss:
261 if (sfile == NULL
262 || filename_cmp (msymbol->filename, sfile) == 0)
263 {
264 file_symbol.minsym = msymbol;
265 file_symbol.objfile = objfile;
266 }
267 break;
268
269 case mst_solib_trampoline:
270
271 /* If a trampoline symbol is found, we prefer to keep
272 looking for the *real* symbol. If the actual symbol
273 is not found, then we'll use the trampoline
274 entry. */
275 if (trampoline_symbol.minsym == NULL)
276 {
277 trampoline_symbol.minsym = msymbol;
278 trampoline_symbol.objfile = objfile;
279 }
280 break;
281
282 case mst_unknown:
283 default:
284 external_symbol.minsym = msymbol;
285 external_symbol.objfile = objfile;
286 /* We have the real symbol. No use looking further. */
287 return true;
288 }
289
290 /* Keep looking. */
291 return false;
292 }
293
294 /* Walk the mangled name hash table, and pass each symbol whose name
295 matches LOOKUP_NAME according to NAMECMP to FOUND. */
296
297 static void
298 lookup_minimal_symbol_mangled (const char *lookup_name,
299 const char *sfile,
300 struct objfile *objfile,
301 struct minimal_symbol **table,
302 unsigned int hash,
303 int (*namecmp) (const char *, const char *),
304 found_minimal_symbols &found)
305 {
306 for (minimal_symbol *msymbol = table[hash];
307 msymbol != NULL;
308 msymbol = msymbol->hash_next)
309 {
310 const char *symbol_name = msymbol->linkage_name ();
311
312 if (namecmp (symbol_name, lookup_name) == 0
313 && found.maybe_collect (sfile, objfile, msymbol))
314 return;
315 }
316 }
317
318 /* Walk the demangled name hash table, and pass each symbol whose name
319 matches LOOKUP_NAME according to MATCHER to FOUND. */
320
321 static void
322 lookup_minimal_symbol_demangled (const lookup_name_info &lookup_name,
323 const char *sfile,
324 struct objfile *objfile,
325 struct minimal_symbol **table,
326 unsigned int hash,
327 symbol_name_matcher_ftype *matcher,
328 found_minimal_symbols &found)
329 {
330 for (minimal_symbol *msymbol = table[hash];
331 msymbol != NULL;
332 msymbol = msymbol->demangled_hash_next)
333 {
334 const char *symbol_name = msymbol->search_name ();
335
336 if (matcher (symbol_name, lookup_name, NULL)
337 && found.maybe_collect (sfile, objfile, msymbol))
338 return;
339 }
340 }
341
342 /* Look through all the current minimal symbol tables and find the
343 first minimal symbol that matches NAME. If OBJF is non-NULL, limit
344 the search to that objfile. If SFILE is non-NULL, the only file-scope
345 symbols considered will be from that source file (global symbols are
346 still preferred). Returns a pointer to the minimal symbol that
347 matches, or NULL if no match is found.
348
349 Note: One instance where there may be duplicate minimal symbols with
350 the same name is when the symbol tables for a shared library and the
351 symbol tables for an executable contain global symbols with the same
352 names (the dynamic linker deals with the duplication).
353
354 It's also possible to have minimal symbols with different mangled
355 names, but identical demangled names. For example, the GNU C++ v3
356 ABI requires the generation of two (or perhaps three) copies of
357 constructor functions --- "in-charge", "not-in-charge", and
358 "allocate" copies; destructors may be duplicated as well.
359 Obviously, there must be distinct mangled names for each of these,
360 but the demangled names are all the same: S::S or S::~S. */
361
362 struct bound_minimal_symbol
363 lookup_minimal_symbol (const char *name, const char *sfile,
364 struct objfile *objf)
365 {
366 found_minimal_symbols found;
367
368 unsigned int mangled_hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
369
370 auto *mangled_cmp
371 = (case_sensitivity == case_sensitive_on
372 ? strcmp
373 : strcasecmp);
374
375 if (sfile != NULL)
376 sfile = lbasename (sfile);
377
378 lookup_name_info lookup_name (name, symbol_name_match_type::FULL);
379
380 for (objfile *objfile : current_program_space->objfiles ())
381 {
382 if (found.external_symbol.minsym != NULL)
383 break;
384
385 if (objf == NULL || objf == objfile
386 || objf == objfile->separate_debug_objfile_backlink)
387 {
388 symbol_lookup_debug_printf ("lookup_minimal_symbol (%s, %s, %s)",
389 name, sfile != NULL ? sfile : "NULL",
390 objfile_debug_name (objfile));
391
392 /* Do two passes: the first over the ordinary hash table,
393 and the second over the demangled hash table. */
394 lookup_minimal_symbol_mangled (name, sfile, objfile,
395 objfile->per_bfd->msymbol_hash,
396 mangled_hash, mangled_cmp, found);
397
398 /* If not found, try the demangled hash table. */
399 if (found.external_symbol.minsym == NULL)
400 {
401 /* Once for each language in the demangled hash names
402 table (usually just zero or one languages). */
403 for (unsigned iter = 0; iter < nr_languages; ++iter)
404 {
405 if (!objfile->per_bfd->demangled_hash_languages.test (iter))
406 continue;
407 enum language lang = (enum language) iter;
408
409 unsigned int hash
410 = (lookup_name.search_name_hash (lang)
411 % MINIMAL_SYMBOL_HASH_SIZE);
412
413 symbol_name_matcher_ftype *match
414 = language_def (lang)->get_symbol_name_matcher
415 (lookup_name);
416 struct minimal_symbol **msymbol_demangled_hash
417 = objfile->per_bfd->msymbol_demangled_hash;
418
419 lookup_minimal_symbol_demangled (lookup_name, sfile, objfile,
420 msymbol_demangled_hash,
421 hash, match, found);
422
423 if (found.external_symbol.minsym != NULL)
424 break;
425 }
426 }
427 }
428 }
429
430 /* External symbols are best. */
431 if (found.external_symbol.minsym != NULL)
432 {
433 if (symbol_lookup_debug)
434 {
435 minimal_symbol *minsym = found.external_symbol.minsym;
436
437 symbol_lookup_debug_printf
438 ("lookup_minimal_symbol (...) = %s (external)",
439 host_address_to_string (minsym));
440 }
441 return found.external_symbol;
442 }
443
444 /* File-local symbols are next best. */
445 if (found.file_symbol.minsym != NULL)
446 {
447 if (symbol_lookup_debug)
448 {
449 minimal_symbol *minsym = found.file_symbol.minsym;
450
451 symbol_lookup_debug_printf
452 ("lookup_minimal_symbol (...) = %s (file-local)",
453 host_address_to_string (minsym));
454 }
455 return found.file_symbol;
456 }
457
458 /* Symbols for shared library trampolines are next best. */
459 if (found.trampoline_symbol.minsym != NULL)
460 {
461 if (symbol_lookup_debug)
462 {
463 minimal_symbol *minsym = found.trampoline_symbol.minsym;
464
465 symbol_lookup_debug_printf
466 ("lookup_minimal_symbol (...) = %s (trampoline)",
467 host_address_to_string (minsym));
468 }
469
470 return found.trampoline_symbol;
471 }
472
473 /* Not found. */
474 symbol_lookup_debug_printf ("lookup_minimal_symbol (...) = NULL");
475 return {};
476 }
477
478 /* See minsyms.h. */
479
480 struct bound_minimal_symbol
481 lookup_bound_minimal_symbol (const char *name)
482 {
483 return lookup_minimal_symbol (name, NULL, NULL);
484 }
485
486 /* See gdbsupport/symbol.h. */
487
488 int
489 find_minimal_symbol_address (const char *name, CORE_ADDR *addr,
490 struct objfile *objfile)
491 {
492 struct bound_minimal_symbol sym
493 = lookup_minimal_symbol (name, NULL, objfile);
494
495 if (sym.minsym != NULL)
496 *addr = sym.value_address ();
497
498 return sym.minsym == NULL;
499 }
500
501 /* Get the lookup name form best suitable for linkage name
502 matching. */
503
504 static const char *
505 linkage_name_str (const lookup_name_info &lookup_name)
506 {
507 /* Unlike most languages (including C++), Ada uses the
508 encoded/linkage name as the search name recorded in symbols. So
509 if debugging in Ada mode, prefer the Ada-encoded name. This also
510 makes Ada's verbatim match syntax ("<...>") work, because
511 "lookup_name.name()" includes the "<>"s, while
512 "lookup_name.ada().lookup_name()" is the encoded name with "<>"s
513 stripped. */
514 if (current_language->la_language == language_ada)
515 return lookup_name.ada ().lookup_name ().c_str ();
516
517 return lookup_name.c_str ();
518 }
519
520 /* See minsyms.h. */
521
522 void
523 iterate_over_minimal_symbols
524 (struct objfile *objf, const lookup_name_info &lookup_name,
525 gdb::function_view<bool (struct minimal_symbol *)> callback)
526 {
527 /* The first pass is over the ordinary hash table. */
528 {
529 const char *name = linkage_name_str (lookup_name);
530 unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
531 auto *mangled_cmp
532 = (case_sensitivity == case_sensitive_on
533 ? strcmp
534 : strcasecmp);
535
536 for (minimal_symbol *iter = objf->per_bfd->msymbol_hash[hash];
537 iter != NULL;
538 iter = iter->hash_next)
539 {
540 if (mangled_cmp (iter->linkage_name (), name) == 0)
541 if (callback (iter))
542 return;
543 }
544 }
545
546 /* The second pass is over the demangled table. Once for each
547 language in the demangled hash names table (usually just zero or
548 one). */
549 for (unsigned liter = 0; liter < nr_languages; ++liter)
550 {
551 if (!objf->per_bfd->demangled_hash_languages.test (liter))
552 continue;
553
554 enum language lang = (enum language) liter;
555 const language_defn *lang_def = language_def (lang);
556 symbol_name_matcher_ftype *name_match
557 = lang_def->get_symbol_name_matcher (lookup_name);
558
559 unsigned int hash
560 = lookup_name.search_name_hash (lang) % MINIMAL_SYMBOL_HASH_SIZE;
561 for (minimal_symbol *iter = objf->per_bfd->msymbol_demangled_hash[hash];
562 iter != NULL;
563 iter = iter->demangled_hash_next)
564 if (name_match (iter->search_name (), lookup_name, NULL))
565 if (callback (iter))
566 return;
567 }
568 }
569
570 /* See minsyms.h. */
571
572 bound_minimal_symbol
573 lookup_minimal_symbol_linkage (const char *name, struct objfile *objf)
574 {
575 unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
576
577 for (objfile *objfile : objf->separate_debug_objfiles ())
578 {
579 for (minimal_symbol *msymbol = objfile->per_bfd->msymbol_hash[hash];
580 msymbol != NULL;
581 msymbol = msymbol->hash_next)
582 {
583 if (strcmp (msymbol->linkage_name (), name) == 0
584 && (msymbol->type () == mst_data
585 || msymbol->type () == mst_bss))
586 return {msymbol, objfile};
587 }
588 }
589
590 return {};
591 }
592
593 /* See minsyms.h. */
594
595 struct bound_minimal_symbol
596 lookup_minimal_symbol_linkage (const char *name, bool only_main)
597 {
598 for (objfile *objfile : current_program_space->objfiles ())
599 {
600 if (objfile->separate_debug_objfile_backlink != nullptr)
601 continue;
602
603 if (only_main && (objfile->flags & OBJF_MAINLINE) == 0)
604 continue;
605
606 bound_minimal_symbol minsym = lookup_minimal_symbol_linkage (name,
607 objfile);
608 if (minsym.minsym != nullptr)
609 return minsym;
610 }
611
612 return {};
613 }
614
615 /* See minsyms.h. */
616
617 struct bound_minimal_symbol
618 lookup_minimal_symbol_text (const char *name, struct objfile *objf)
619 {
620 struct minimal_symbol *msymbol;
621 struct bound_minimal_symbol found_symbol;
622 struct bound_minimal_symbol found_file_symbol;
623
624 unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
625
626 for (objfile *objfile : current_program_space->objfiles ())
627 {
628 if (found_symbol.minsym != NULL)
629 break;
630
631 if (objf == NULL || objf == objfile
632 || objf == objfile->separate_debug_objfile_backlink)
633 {
634 for (msymbol = objfile->per_bfd->msymbol_hash[hash];
635 msymbol != NULL && found_symbol.minsym == NULL;
636 msymbol = msymbol->hash_next)
637 {
638 if (strcmp (msymbol->linkage_name (), name) == 0 &&
639 (msymbol->type () == mst_text
640 || msymbol->type () == mst_text_gnu_ifunc
641 || msymbol->type () == mst_file_text))
642 {
643 switch (msymbol->type ())
644 {
645 case mst_file_text:
646 found_file_symbol.minsym = msymbol;
647 found_file_symbol.objfile = objfile;
648 break;
649 default:
650 found_symbol.minsym = msymbol;
651 found_symbol.objfile = objfile;
652 break;
653 }
654 }
655 }
656 }
657 }
658 /* External symbols are best. */
659 if (found_symbol.minsym)
660 return found_symbol;
661
662 /* File-local symbols are next best. */
663 return found_file_symbol;
664 }
665
666 /* See minsyms.h. */
667
668 struct minimal_symbol *
669 lookup_minimal_symbol_by_pc_name (CORE_ADDR pc, const char *name,
670 struct objfile *objf)
671 {
672 struct minimal_symbol *msymbol;
673
674 unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
675
676 for (objfile *objfile : current_program_space->objfiles ())
677 {
678 if (objf == NULL || objf == objfile
679 || objf == objfile->separate_debug_objfile_backlink)
680 {
681 for (msymbol = objfile->per_bfd->msymbol_hash[hash];
682 msymbol != NULL;
683 msymbol = msymbol->hash_next)
684 {
685 if (msymbol->value_address (objfile) == pc
686 && strcmp (msymbol->linkage_name (), name) == 0)
687 return msymbol;
688 }
689 }
690 }
691
692 return NULL;
693 }
694
695 /* A helper function that makes *PC section-relative. This searches
696 the sections of OBJFILE and if *PC is in a section, it subtracts
697 the section offset, stores the result into UNREL_ADDR, and returns
698 true. Otherwise it returns false. */
699
700 static int
701 frob_address (struct objfile *objfile, CORE_ADDR pc,
702 unrelocated_addr *unrel_addr)
703 {
704 for (obj_section *iter : objfile->sections ())
705 {
706 if (pc >= iter->addr () && pc < iter->endaddr ())
707 {
708 *unrel_addr = unrelocated_addr (pc - iter->offset ());
709 return 1;
710 }
711 }
712
713 return 0;
714 }
715
716 /* Helper for lookup_minimal_symbol_by_pc_section. Convert a
717 lookup_msym_prefer to a minimal_symbol_type. */
718
719 static minimal_symbol_type
720 msym_prefer_to_msym_type (lookup_msym_prefer prefer)
721 {
722 switch (prefer)
723 {
724 case lookup_msym_prefer::TEXT:
725 return mst_text;
726 case lookup_msym_prefer::TRAMPOLINE:
727 return mst_solib_trampoline;
728 case lookup_msym_prefer::GNU_IFUNC:
729 return mst_text_gnu_ifunc;
730 }
731
732 /* Assert here instead of in a default switch case above so that
733 -Wswitch warns if a new enumerator is added. */
734 gdb_assert_not_reached ("unhandled lookup_msym_prefer");
735 }
736
737 /* See minsyms.h.
738
739 Note that we need to look through ALL the minimal symbol tables
740 before deciding on the symbol that comes closest to the specified PC.
741 This is because objfiles can overlap, for example objfile A has .text
742 at 0x100 and .data at 0x40000 and objfile B has .text at 0x234 and
743 .data at 0x40048. */
744
745 bound_minimal_symbol
746 lookup_minimal_symbol_by_pc_section (CORE_ADDR pc_in, struct obj_section *section,
747 lookup_msym_prefer prefer,
748 bound_minimal_symbol *previous)
749 {
750 int lo;
751 int hi;
752 int newobj;
753 struct minimal_symbol *msymbol;
754 struct minimal_symbol *best_symbol = NULL;
755 struct objfile *best_objfile = NULL;
756 struct bound_minimal_symbol result;
757
758 if (previous != nullptr)
759 {
760 previous->minsym = nullptr;
761 previous->objfile = nullptr;
762 }
763
764 if (section == NULL)
765 {
766 section = find_pc_section (pc_in);
767 if (section == NULL)
768 return {};
769 }
770
771 minimal_symbol_type want_type = msym_prefer_to_msym_type (prefer);
772
773 /* We can not require the symbol found to be in section, because
774 e.g. IRIX 6.5 mdebug relies on this code returning an absolute
775 symbol - but find_pc_section won't return an absolute section and
776 hence the code below would skip over absolute symbols. We can
777 still take advantage of the call to find_pc_section, though - the
778 object file still must match. In case we have separate debug
779 files, search both the file and its separate debug file. There's
780 no telling which one will have the minimal symbols. */
781
782 gdb_assert (section != NULL);
783
784 for (objfile *objfile : section->objfile->separate_debug_objfiles ())
785 {
786 CORE_ADDR pc = pc_in;
787
788 /* If this objfile has a minimal symbol table, go search it
789 using a binary search. */
790
791 if (objfile->per_bfd->minimal_symbol_count > 0)
792 {
793 int best_zero_sized = -1;
794
795 msymbol = objfile->per_bfd->msymbols.get ();
796 lo = 0;
797 hi = objfile->per_bfd->minimal_symbol_count - 1;
798
799 /* This code assumes that the minimal symbols are sorted by
800 ascending address values. If the pc value is greater than or
801 equal to the first symbol's address, then some symbol in this
802 minimal symbol table is a suitable candidate for being the
803 "best" symbol. This includes the last real symbol, for cases
804 where the pc value is larger than any address in this vector.
805
806 By iterating until the address associated with the current
807 hi index (the endpoint of the test interval) is less than
808 or equal to the desired pc value, we accomplish two things:
809 (1) the case where the pc value is larger than any minimal
810 symbol address is trivially solved, (2) the address associated
811 with the hi index is always the one we want when the iteration
812 terminates. In essence, we are iterating the test interval
813 down until the pc value is pushed out of it from the high end.
814
815 Warning: this code is trickier than it would appear at first. */
816
817 unrelocated_addr unrel_pc;
818 if (frob_address (objfile, pc, &unrel_pc)
819 && unrel_pc >= msymbol[lo].unrelocated_address ())
820 {
821 while (msymbol[hi].unrelocated_address () > unrel_pc)
822 {
823 /* pc is still strictly less than highest address. */
824 /* Note "new" will always be >= lo. */
825 newobj = (lo + hi) / 2;
826 if ((msymbol[newobj].unrelocated_address () >= unrel_pc)
827 || (lo == newobj))
828 {
829 hi = newobj;
830 }
831 else
832 {
833 lo = newobj;
834 }
835 }
836
837 /* If we have multiple symbols at the same address, we want
838 hi to point to the last one. That way we can find the
839 right symbol if it has an index greater than hi. */
840 while (hi < objfile->per_bfd->minimal_symbol_count - 1
841 && (msymbol[hi].unrelocated_address ()
842 == msymbol[hi + 1].unrelocated_address ()))
843 hi++;
844
845 /* Skip various undesirable symbols. */
846 while (hi >= 0)
847 {
848 /* Skip any absolute symbols. This is apparently
849 what adb and dbx do, and is needed for the CM-5.
850 There are two known possible problems: (1) on
851 ELF, apparently end, edata, etc. are absolute.
852 Not sure ignoring them here is a big deal, but if
853 we want to use them, the fix would go in
854 elfread.c. (2) I think shared library entry
855 points on the NeXT are absolute. If we want
856 special handling for this it probably should be
857 triggered by a special mst_abs_or_lib or some
858 such. */
859
860 if (msymbol[hi].type () == mst_abs)
861 {
862 hi--;
863 continue;
864 }
865
866 /* If SECTION was specified, skip any symbol from
867 wrong section. */
868 if (section
869 /* Some types of debug info, such as COFF,
870 don't fill the bfd_section member, so don't
871 throw away symbols on those platforms. */
872 && msymbol[hi].obj_section (objfile) != nullptr
873 && (!matching_obj_sections
874 (msymbol[hi].obj_section (objfile),
875 section)))
876 {
877 hi--;
878 continue;
879 }
880
881 /* If we are looking for a trampoline and this is a
882 text symbol, or the other way around, check the
883 preceding symbol too. If they are otherwise
884 identical prefer that one. */
885 if (hi > 0
886 && msymbol[hi].type () != want_type
887 && msymbol[hi - 1].type () == want_type
888 && (msymbol[hi].size () == msymbol[hi - 1].size ())
889 && (msymbol[hi].unrelocated_address ()
890 == msymbol[hi - 1].unrelocated_address ())
891 && (msymbol[hi].obj_section (objfile)
892 == msymbol[hi - 1].obj_section (objfile)))
893 {
894 hi--;
895 continue;
896 }
897
898 /* If the minimal symbol has a zero size, save it
899 but keep scanning backwards looking for one with
900 a non-zero size. A zero size may mean that the
901 symbol isn't an object or function (e.g. a
902 label), or it may just mean that the size was not
903 specified. */
904 if (msymbol[hi].size () == 0)
905 {
906 if (best_zero_sized == -1)
907 best_zero_sized = hi;
908 hi--;
909 continue;
910 }
911
912 /* If we are past the end of the current symbol, try
913 the previous symbol if it has a larger overlapping
914 size. This happens on i686-pc-linux-gnu with glibc;
915 the nocancel variants of system calls are inside
916 the cancellable variants, but both have sizes. */
917 if (hi > 0
918 && msymbol[hi].size () != 0
919 && unrel_pc >= msymbol[hi].unrelocated_end_address ()
920 && unrel_pc < msymbol[hi - 1].unrelocated_end_address ())
921 {
922 hi--;
923 continue;
924 }
925
926 /* Otherwise, this symbol must be as good as we're going
927 to get. */
928 break;
929 }
930
931 /* If HI has a zero size, and best_zero_sized is set,
932 then we had two or more zero-sized symbols; prefer
933 the first one we found (which may have a higher
934 address). Also, if we ran off the end, be sure
935 to back up. */
936 if (best_zero_sized != -1
937 && (hi < 0 || msymbol[hi].size () == 0))
938 hi = best_zero_sized;
939
940 /* If the minimal symbol has a non-zero size, and this
941 PC appears to be outside the symbol's contents, then
942 refuse to use this symbol. If we found a zero-sized
943 symbol with an address greater than this symbol's,
944 use that instead. We assume that if symbols have
945 specified sizes, they do not overlap. */
946
947 if (hi >= 0
948 && msymbol[hi].size () != 0
949 && unrel_pc >= msymbol[hi].unrelocated_end_address ())
950 {
951 if (best_zero_sized != -1)
952 hi = best_zero_sized;
953 else
954 {
955 /* If needed record this symbol as the closest
956 previous symbol. */
957 if (previous != nullptr)
958 {
959 if (previous->minsym == nullptr
960 || (msymbol[hi].unrelocated_address ()
961 > previous->minsym->unrelocated_address ()))
962 {
963 previous->minsym = &msymbol[hi];
964 previous->objfile = objfile;
965 }
966 }
967 /* Go on to the next object file. */
968 continue;
969 }
970 }
971
972 /* The minimal symbol indexed by hi now is the best one in this
973 objfile's minimal symbol table. See if it is the best one
974 overall. */
975
976 if (hi >= 0
977 && ((best_symbol == NULL) ||
978 (best_symbol->unrelocated_address () <
979 msymbol[hi].unrelocated_address ())))
980 {
981 best_symbol = &msymbol[hi];
982 best_objfile = objfile;
983 }
984 }
985 }
986 }
987
988 result.minsym = best_symbol;
989 result.objfile = best_objfile;
990 return result;
991 }
992
993 /* See minsyms.h. */
994
995 struct bound_minimal_symbol
996 lookup_minimal_symbol_by_pc (CORE_ADDR pc)
997 {
998 return lookup_minimal_symbol_by_pc_section (pc, NULL);
999 }
1000
1001 /* Return non-zero iff PC is in an STT_GNU_IFUNC function resolver. */
1002
1003 bool
1004 in_gnu_ifunc_stub (CORE_ADDR pc)
1005 {
1006 bound_minimal_symbol msymbol
1007 = lookup_minimal_symbol_by_pc_section (pc, NULL,
1008 lookup_msym_prefer::GNU_IFUNC);
1009 return msymbol.minsym && msymbol.minsym->type () == mst_text_gnu_ifunc;
1010 }
1011
1012 /* See elf_gnu_ifunc_resolve_addr for its real implementation. */
1013
1014 static CORE_ADDR
1015 stub_gnu_ifunc_resolve_addr (struct gdbarch *gdbarch, CORE_ADDR pc)
1016 {
1017 error (_("GDB cannot resolve STT_GNU_IFUNC symbol at address %s without "
1018 "the ELF support compiled in."),
1019 paddress (gdbarch, pc));
1020 }
1021
1022 /* See elf_gnu_ifunc_resolve_name for its real implementation. */
1023
1024 static bool
1025 stub_gnu_ifunc_resolve_name (const char *function_name,
1026 CORE_ADDR *function_address_p)
1027 {
1028 error (_("GDB cannot resolve STT_GNU_IFUNC symbol \"%s\" without "
1029 "the ELF support compiled in."),
1030 function_name);
1031 }
1032
1033 /* See elf_gnu_ifunc_resolver_stop for its real implementation. */
1034
1035 static void
1036 stub_gnu_ifunc_resolver_stop (code_breakpoint *b)
1037 {
1038 internal_error (_("elf_gnu_ifunc_resolver_stop cannot be reached."));
1039 }
1040
1041 /* See elf_gnu_ifunc_resolver_return_stop for its real implementation. */
1042
1043 static void
1044 stub_gnu_ifunc_resolver_return_stop (code_breakpoint *b)
1045 {
1046 internal_error (_("elf_gnu_ifunc_resolver_return_stop cannot be reached."));
1047 }
1048
1049 /* See elf_gnu_ifunc_fns for its real implementation. */
1050
1051 static const struct gnu_ifunc_fns stub_gnu_ifunc_fns =
1052 {
1053 stub_gnu_ifunc_resolve_addr,
1054 stub_gnu_ifunc_resolve_name,
1055 stub_gnu_ifunc_resolver_stop,
1056 stub_gnu_ifunc_resolver_return_stop,
1057 };
1058
1059 /* A placeholder for &elf_gnu_ifunc_fns. */
1060
1061 const struct gnu_ifunc_fns *gnu_ifunc_fns_p = &stub_gnu_ifunc_fns;
1062
1063 \f
1064
1065 /* Return leading symbol character for a BFD. If BFD is NULL,
1066 return the leading symbol character from the main objfile. */
1067
1068 static int
1069 get_symbol_leading_char (bfd *abfd)
1070 {
1071 if (abfd != NULL)
1072 return bfd_get_symbol_leading_char (abfd);
1073 if (current_program_space->symfile_object_file != NULL)
1074 {
1075 objfile *objf = current_program_space->symfile_object_file;
1076 if (objf->obfd != NULL)
1077 return bfd_get_symbol_leading_char (objf->obfd.get ());
1078 }
1079 return 0;
1080 }
1081
1082 /* See minsyms.h. */
1083
1084 minimal_symbol_reader::minimal_symbol_reader (struct objfile *obj)
1085 : m_objfile (obj),
1086 m_msym_bunch (NULL),
1087 /* Note that presetting m_msym_bunch_index to BUNCH_SIZE causes the
1088 first call to save a minimal symbol to allocate the memory for
1089 the first bunch. */
1090 m_msym_bunch_index (BUNCH_SIZE),
1091 m_msym_count (0)
1092 {
1093 }
1094
1095 /* Discard the currently collected minimal symbols, if any. If we wish
1096 to save them for later use, we must have already copied them somewhere
1097 else before calling this function. */
1098
1099 minimal_symbol_reader::~minimal_symbol_reader ()
1100 {
1101 struct msym_bunch *next;
1102
1103 while (m_msym_bunch != NULL)
1104 {
1105 next = m_msym_bunch->next;
1106 xfree (m_msym_bunch);
1107 m_msym_bunch = next;
1108 }
1109 }
1110
1111 /* See minsyms.h. */
1112
1113 void
1114 minimal_symbol_reader::record (const char *name, unrelocated_addr address,
1115 enum minimal_symbol_type ms_type)
1116 {
1117 int section;
1118
1119 switch (ms_type)
1120 {
1121 case mst_text:
1122 case mst_text_gnu_ifunc:
1123 case mst_file_text:
1124 case mst_solib_trampoline:
1125 section = SECT_OFF_TEXT (m_objfile);
1126 break;
1127 case mst_data:
1128 case mst_data_gnu_ifunc:
1129 case mst_file_data:
1130 section = SECT_OFF_DATA (m_objfile);
1131 break;
1132 case mst_bss:
1133 case mst_file_bss:
1134 section = SECT_OFF_BSS (m_objfile);
1135 break;
1136 default:
1137 section = -1;
1138 }
1139
1140 record_with_info (name, address, ms_type, section);
1141 }
1142
1143 /* Convert an enumerator of type minimal_symbol_type to its string
1144 representation. */
1145
1146 static const char *
1147 mst_str (minimal_symbol_type t)
1148 {
1149 #define MST_TO_STR(x) case x: return #x;
1150 switch (t)
1151 {
1152 MST_TO_STR (mst_unknown);
1153 MST_TO_STR (mst_text);
1154 MST_TO_STR (mst_text_gnu_ifunc);
1155 MST_TO_STR (mst_slot_got_plt);
1156 MST_TO_STR (mst_data);
1157 MST_TO_STR (mst_bss);
1158 MST_TO_STR (mst_abs);
1159 MST_TO_STR (mst_solib_trampoline);
1160 MST_TO_STR (mst_file_text);
1161 MST_TO_STR (mst_file_data);
1162 MST_TO_STR (mst_file_bss);
1163
1164 default:
1165 return "mst_???";
1166 }
1167 #undef MST_TO_STR
1168 }
1169
1170 /* See minsyms.h. */
1171
1172 struct minimal_symbol *
1173 minimal_symbol_reader::record_full (gdb::string_view name,
1174 bool copy_name, unrelocated_addr address,
1175 enum minimal_symbol_type ms_type,
1176 int section)
1177 {
1178 struct msym_bunch *newobj;
1179 struct minimal_symbol *msymbol;
1180
1181 /* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into
1182 the minimal symbols, because if there is also another symbol
1183 at the same address (e.g. the first function of the file),
1184 lookup_minimal_symbol_by_pc would have no way of getting the
1185 right one. */
1186 if (ms_type == mst_file_text && name[0] == 'g'
1187 && (name == GCC_COMPILED_FLAG_SYMBOL
1188 || name == GCC2_COMPILED_FLAG_SYMBOL))
1189 return (NULL);
1190
1191 /* It's safe to strip the leading char here once, since the name
1192 is also stored stripped in the minimal symbol table. */
1193 if (name[0] == get_symbol_leading_char (m_objfile->obfd.get ()))
1194 name = name.substr (1);
1195
1196 if (ms_type == mst_file_text && startswith (name, "__gnu_compiled"))
1197 return (NULL);
1198
1199 symtab_create_debug_printf_v ("recording minsym: %-21s %18s %4d %.*s",
1200 mst_str (ms_type),
1201 hex_string (LONGEST (address)),
1202 section, (int) name.size (), name.data ());
1203
1204 if (m_msym_bunch_index == BUNCH_SIZE)
1205 {
1206 newobj = XCNEW (struct msym_bunch);
1207 m_msym_bunch_index = 0;
1208 newobj->next = m_msym_bunch;
1209 m_msym_bunch = newobj;
1210 }
1211 msymbol = &m_msym_bunch->contents[m_msym_bunch_index];
1212 msymbol->set_language (language_unknown,
1213 &m_objfile->per_bfd->storage_obstack);
1214
1215 if (copy_name)
1216 msymbol->m_name = obstack_strndup (&m_objfile->per_bfd->storage_obstack,
1217 name.data (), name.size ());
1218 else
1219 msymbol->m_name = name.data ();
1220
1221 msymbol->set_unrelocated_address (address);
1222 msymbol->set_section_index (section);
1223
1224 msymbol->set_type (ms_type);
1225
1226 /* If we already read minimal symbols for this objfile, then don't
1227 ever allocate a new one. */
1228 if (!m_objfile->per_bfd->minsyms_read)
1229 {
1230 m_msym_bunch_index++;
1231 m_objfile->per_bfd->n_minsyms++;
1232 }
1233 m_msym_count++;
1234 return msymbol;
1235 }
1236
1237 /* Compare two minimal symbols by address and return true if FN1's address
1238 is less than FN2's, so that we sort into unsigned numeric order.
1239 Within groups with the same address, sort by name. */
1240
1241 static inline bool
1242 minimal_symbol_is_less_than (const minimal_symbol &fn1,
1243 const minimal_symbol &fn2)
1244 {
1245 if ((&fn1)->unrelocated_address () < (&fn2)->unrelocated_address ())
1246 {
1247 return true; /* addr 1 is less than addr 2. */
1248 }
1249 else if ((&fn1)->unrelocated_address () > (&fn2)->unrelocated_address ())
1250 {
1251 return false; /* addr 1 is greater than addr 2. */
1252 }
1253 else
1254 /* addrs are equal: sort by name */
1255 {
1256 const char *name1 = fn1.linkage_name ();
1257 const char *name2 = fn2.linkage_name ();
1258
1259 if (name1 && name2) /* both have names */
1260 return strcmp (name1, name2) < 0;
1261 else if (name2)
1262 return true; /* fn1 has no name, so it is "less". */
1263 else if (name1) /* fn2 has no name, so it is "less". */
1264 return false;
1265 else
1266 return false; /* Neither has a name, so they're equal. */
1267 }
1268 }
1269
1270 /* Compact duplicate entries out of a minimal symbol table by walking
1271 through the table and compacting out entries with duplicate addresses
1272 and matching names. Return the number of entries remaining.
1273
1274 On entry, the table resides between msymbol[0] and msymbol[mcount].
1275 On exit, it resides between msymbol[0] and msymbol[result_count].
1276
1277 When files contain multiple sources of symbol information, it is
1278 possible for the minimal symbol table to contain many duplicate entries.
1279 As an example, SVR4 systems use ELF formatted object files, which
1280 usually contain at least two different types of symbol tables (a
1281 standard ELF one and a smaller dynamic linking table), as well as
1282 DWARF debugging information for files compiled with -g.
1283
1284 Without compacting, the minimal symbol table for gdb itself contains
1285 over a 1000 duplicates, about a third of the total table size. Aside
1286 from the potential trap of not noticing that two successive entries
1287 identify the same location, this duplication impacts the time required
1288 to linearly scan the table, which is done in a number of places. So we
1289 just do one linear scan here and toss out the duplicates.
1290
1291 Since the different sources of information for each symbol may
1292 have different levels of "completeness", we may have duplicates
1293 that have one entry with type "mst_unknown" and the other with a
1294 known type. So if the one we are leaving alone has type mst_unknown,
1295 overwrite its type with the type from the one we are compacting out. */
1296
1297 static int
1298 compact_minimal_symbols (struct minimal_symbol *msymbol, int mcount,
1299 struct objfile *objfile)
1300 {
1301 struct minimal_symbol *copyfrom;
1302 struct minimal_symbol *copyto;
1303
1304 if (mcount > 0)
1305 {
1306 copyfrom = copyto = msymbol;
1307 while (copyfrom < msymbol + mcount - 1)
1308 {
1309 if (copyfrom->unrelocated_address ()
1310 == (copyfrom + 1)->unrelocated_address ()
1311 && (copyfrom->section_index ()
1312 == (copyfrom + 1)->section_index ())
1313 && strcmp (copyfrom->linkage_name (),
1314 (copyfrom + 1)->linkage_name ()) == 0)
1315 {
1316 if ((copyfrom + 1)->type () == mst_unknown)
1317 (copyfrom + 1)->set_type (copyfrom->type ());
1318
1319 copyfrom++;
1320 }
1321 else
1322 *copyto++ = *copyfrom++;
1323 }
1324 *copyto++ = *copyfrom++;
1325 mcount = copyto - msymbol;
1326 }
1327 return (mcount);
1328 }
1329
1330 static void
1331 clear_minimal_symbol_hash_tables (struct objfile *objfile)
1332 {
1333 for (size_t i = 0; i < MINIMAL_SYMBOL_HASH_SIZE; i++)
1334 {
1335 objfile->per_bfd->msymbol_hash[i] = 0;
1336 objfile->per_bfd->msymbol_demangled_hash[i] = 0;
1337 }
1338 }
1339
1340 /* This struct is used to store values we compute for msymbols on the
1341 background threads but don't need to keep around long term. */
1342 struct computed_hash_values
1343 {
1344 /* Length of the linkage_name of the symbol. */
1345 size_t name_length;
1346 /* Hash code (using fast_hash) of the linkage_name. */
1347 hashval_t mangled_name_hash;
1348 /* The msymbol_hash of the linkage_name. */
1349 unsigned int minsym_hash;
1350 /* The msymbol_hash of the search_name. */
1351 unsigned int minsym_demangled_hash;
1352 };
1353
1354 /* Build (or rebuild) the minimal symbol hash tables. This is necessary
1355 after compacting or sorting the table since the entries move around
1356 thus causing the internal minimal_symbol pointers to become jumbled. */
1357
1358 static void
1359 build_minimal_symbol_hash_tables
1360 (struct objfile *objfile,
1361 const std::vector<computed_hash_values>& hash_values)
1362 {
1363 int i;
1364 struct minimal_symbol *msym;
1365
1366 /* (Re)insert the actual entries. */
1367 int mcount = objfile->per_bfd->minimal_symbol_count;
1368 for ((i = 0,
1369 msym = objfile->per_bfd->msymbols.get ());
1370 i < mcount;
1371 i++, msym++)
1372 {
1373 msym->hash_next = 0;
1374 add_minsym_to_hash_table (msym, objfile->per_bfd->msymbol_hash,
1375 hash_values[i].minsym_hash);
1376
1377 msym->demangled_hash_next = 0;
1378 if (msym->search_name () != msym->linkage_name ())
1379 add_minsym_to_demangled_hash_table
1380 (msym, objfile, hash_values[i].minsym_demangled_hash);
1381 }
1382 }
1383
1384 /* Add the minimal symbols in the existing bunches to the objfile's official
1385 minimal symbol table. In most cases there is no minimal symbol table yet
1386 for this objfile, and the existing bunches are used to create one. Once
1387 in a while (for shared libraries for example), we add symbols (e.g. common
1388 symbols) to an existing objfile. */
1389
1390 void
1391 minimal_symbol_reader::install ()
1392 {
1393 int mcount;
1394 struct msym_bunch *bunch;
1395 struct minimal_symbol *msymbols;
1396 int alloc_count;
1397
1398 if (m_objfile->per_bfd->minsyms_read)
1399 return;
1400
1401 if (m_msym_count > 0)
1402 {
1403 symtab_create_debug_printf ("installing %d minimal symbols of objfile %s",
1404 m_msym_count, objfile_name (m_objfile));
1405
1406 /* Allocate enough space, into which we will gather the bunches
1407 of new and existing minimal symbols, sort them, and then
1408 compact out the duplicate entries. Once we have a final
1409 table, we will give back the excess space. */
1410
1411 alloc_count = m_msym_count + m_objfile->per_bfd->minimal_symbol_count;
1412 gdb::unique_xmalloc_ptr<minimal_symbol>
1413 msym_holder (XNEWVEC (minimal_symbol, alloc_count));
1414 msymbols = msym_holder.get ();
1415
1416 /* Copy in the existing minimal symbols, if there are any. */
1417
1418 if (m_objfile->per_bfd->minimal_symbol_count)
1419 memcpy (msymbols, m_objfile->per_bfd->msymbols.get (),
1420 m_objfile->per_bfd->minimal_symbol_count
1421 * sizeof (struct minimal_symbol));
1422
1423 /* Walk through the list of minimal symbol bunches, adding each symbol
1424 to the new contiguous array of symbols. Note that we start with the
1425 current, possibly partially filled bunch (thus we use the current
1426 msym_bunch_index for the first bunch we copy over), and thereafter
1427 each bunch is full. */
1428
1429 mcount = m_objfile->per_bfd->minimal_symbol_count;
1430
1431 for (bunch = m_msym_bunch; bunch != NULL; bunch = bunch->next)
1432 {
1433 memcpy (&msymbols[mcount], &bunch->contents[0],
1434 m_msym_bunch_index * sizeof (struct minimal_symbol));
1435 mcount += m_msym_bunch_index;
1436 m_msym_bunch_index = BUNCH_SIZE;
1437 }
1438
1439 /* Sort the minimal symbols by address. */
1440
1441 std::sort (msymbols, msymbols + mcount, minimal_symbol_is_less_than);
1442
1443 /* Compact out any duplicates, and free up whatever space we are
1444 no longer using. */
1445
1446 mcount = compact_minimal_symbols (msymbols, mcount, m_objfile);
1447 msym_holder.reset (XRESIZEVEC (struct minimal_symbol,
1448 msym_holder.release (),
1449 mcount));
1450
1451 /* Attach the minimal symbol table to the specified objfile.
1452 The strings themselves are also located in the storage_obstack
1453 of this objfile. */
1454
1455 if (m_objfile->per_bfd->minimal_symbol_count != 0)
1456 clear_minimal_symbol_hash_tables (m_objfile);
1457
1458 m_objfile->per_bfd->minimal_symbol_count = mcount;
1459 m_objfile->per_bfd->msymbols = std::move (msym_holder);
1460
1461 #if CXX_STD_THREAD
1462 /* Mutex that is used when modifying or accessing the demangled
1463 hash table. */
1464 std::mutex demangled_mutex;
1465 #endif
1466
1467 std::vector<computed_hash_values> hash_values (mcount);
1468
1469 msymbols = m_objfile->per_bfd->msymbols.get ();
1470 /* Arbitrarily require at least 10 elements in a thread. */
1471 gdb::parallel_for_each (10, &msymbols[0], &msymbols[mcount],
1472 [&] (minimal_symbol *start, minimal_symbol *end)
1473 {
1474 for (minimal_symbol *msym = start; msym < end; ++msym)
1475 {
1476 size_t idx = msym - msymbols;
1477 hash_values[idx].name_length = strlen (msym->linkage_name ());
1478 if (!msym->name_set)
1479 {
1480 /* This will be freed later, by compute_and_set_names. */
1481 gdb::unique_xmalloc_ptr<char> demangled_name
1482 = symbol_find_demangled_name (msym, msym->linkage_name ());
1483 msym->set_demangled_name
1484 (demangled_name.release (),
1485 &m_objfile->per_bfd->storage_obstack);
1486 msym->name_set = 1;
1487 }
1488 /* This mangled_name_hash computation has to be outside of
1489 the name_set check, or compute_and_set_names below will
1490 be called with an invalid hash value. */
1491 hash_values[idx].mangled_name_hash
1492 = fast_hash (msym->linkage_name (),
1493 hash_values[idx].name_length);
1494 hash_values[idx].minsym_hash
1495 = msymbol_hash (msym->linkage_name ());
1496 /* We only use this hash code if the search name differs
1497 from the linkage name. See the code in
1498 build_minimal_symbol_hash_tables. */
1499 if (msym->search_name () != msym->linkage_name ())
1500 hash_values[idx].minsym_demangled_hash
1501 = search_name_hash (msym->language (), msym->search_name ());
1502 }
1503 {
1504 /* To limit how long we hold the lock, we only acquire it here
1505 and not while we demangle the names above. */
1506 #if CXX_STD_THREAD
1507 std::lock_guard<std::mutex> guard (demangled_mutex);
1508 #endif
1509 for (minimal_symbol *msym = start; msym < end; ++msym)
1510 {
1511 size_t idx = msym - msymbols;
1512 msym->compute_and_set_names
1513 (gdb::string_view (msym->linkage_name (),
1514 hash_values[idx].name_length),
1515 false,
1516 m_objfile->per_bfd,
1517 hash_values[idx].mangled_name_hash);
1518 }
1519 }
1520 });
1521
1522 build_minimal_symbol_hash_tables (m_objfile, hash_values);
1523 }
1524 }
1525
1526 /* Check if PC is in a shared library trampoline code stub.
1527 Return minimal symbol for the trampoline entry or NULL if PC is not
1528 in a trampoline code stub. */
1529
1530 static struct minimal_symbol *
1531 lookup_solib_trampoline_symbol_by_pc (CORE_ADDR pc)
1532 {
1533 bound_minimal_symbol msymbol
1534 = lookup_minimal_symbol_by_pc_section (pc, NULL,
1535 lookup_msym_prefer::TRAMPOLINE);
1536
1537 if (msymbol.minsym != NULL
1538 && msymbol.minsym->type () == mst_solib_trampoline)
1539 return msymbol.minsym;
1540 return NULL;
1541 }
1542
1543 /* If PC is in a shared library trampoline code stub, return the
1544 address of the `real' function belonging to the stub.
1545 Return 0 if PC is not in a trampoline code stub or if the real
1546 function is not found in the minimal symbol table.
1547
1548 We may fail to find the right function if a function with the
1549 same name is defined in more than one shared library, but this
1550 is considered bad programming style. We could return 0 if we find
1551 a duplicate function in case this matters someday. */
1552
1553 CORE_ADDR
1554 find_solib_trampoline_target (frame_info_ptr frame, CORE_ADDR pc)
1555 {
1556 struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc);
1557
1558 if (tsymbol != NULL)
1559 {
1560 for (objfile *objfile : current_program_space->objfiles ())
1561 {
1562 for (minimal_symbol *msymbol : objfile->msymbols ())
1563 {
1564 /* Also handle minimal symbols pointing to function
1565 descriptors. */
1566 if ((msymbol->type () == mst_text
1567 || msymbol->type () == mst_text_gnu_ifunc
1568 || msymbol->type () == mst_data
1569 || msymbol->type () == mst_data_gnu_ifunc)
1570 && strcmp (msymbol->linkage_name (),
1571 tsymbol->linkage_name ()) == 0)
1572 {
1573 CORE_ADDR func;
1574
1575 /* Ignore data symbols that are not function
1576 descriptors. */
1577 if (msymbol_is_function (objfile, msymbol, &func))
1578 return func;
1579 }
1580 }
1581 }
1582 }
1583 return 0;
1584 }
1585
1586 /* See minsyms.h. */
1587
1588 CORE_ADDR
1589 minimal_symbol_upper_bound (struct bound_minimal_symbol minsym)
1590 {
1591 short section;
1592 struct obj_section *obj_section;
1593 CORE_ADDR result;
1594 struct minimal_symbol *iter, *msymbol;
1595
1596 gdb_assert (minsym.minsym != NULL);
1597
1598 /* If the minimal symbol has a size, use it. Otherwise use the
1599 lesser of the next minimal symbol in the same section, or the end
1600 of the section, as the end of the function. */
1601
1602 if (minsym.minsym->size () != 0)
1603 return minsym.value_address () + minsym.minsym->size ();
1604
1605 /* Step over other symbols at this same address, and symbols in
1606 other sections, to find the next symbol in this section with a
1607 different address. */
1608
1609 struct minimal_symbol *past_the_end
1610 = (minsym.objfile->per_bfd->msymbols.get ()
1611 + minsym.objfile->per_bfd->minimal_symbol_count);
1612 msymbol = minsym.minsym;
1613 section = msymbol->section_index ();
1614 for (iter = msymbol + 1; iter != past_the_end; ++iter)
1615 {
1616 if ((iter->unrelocated_address ()
1617 != msymbol->unrelocated_address ())
1618 && iter->section_index () == section)
1619 break;
1620 }
1621
1622 obj_section = minsym.obj_section ();
1623 if (iter != past_the_end
1624 && (iter->value_address (minsym.objfile)
1625 < obj_section->endaddr ()))
1626 result = iter->value_address (minsym.objfile);
1627 else
1628 /* We got the start address from the last msymbol in the objfile.
1629 So the end address is the end of the section. */
1630 result = obj_section->endaddr ();
1631
1632 return result;
1633 }
1634
1635 /* See minsyms.h. */
1636
1637 type *
1638 find_minsym_type_and_address (minimal_symbol *msymbol,
1639 struct objfile *objfile,
1640 CORE_ADDR *address_p)
1641 {
1642 bound_minimal_symbol bound_msym = {msymbol, objfile};
1643 struct obj_section *section = msymbol->obj_section (objfile);
1644 enum minimal_symbol_type type = msymbol->type ();
1645
1646 bool is_tls = (section != NULL
1647 && section->the_bfd_section->flags & SEC_THREAD_LOCAL);
1648
1649 /* The minimal symbol might point to a function descriptor;
1650 resolve it to the actual code address instead. */
1651 CORE_ADDR addr;
1652 if (is_tls)
1653 {
1654 /* Addresses of TLS symbols are really offsets into a
1655 per-objfile/per-thread storage block. */
1656 addr = CORE_ADDR (bound_msym.minsym->unrelocated_address ());
1657 }
1658 else if (msymbol_is_function (objfile, msymbol, &addr))
1659 {
1660 if (addr != bound_msym.value_address ())
1661 {
1662 /* This means we resolved a function descriptor, and we now
1663 have an address for a code/text symbol instead of a data
1664 symbol. */
1665 if (msymbol->type () == mst_data_gnu_ifunc)
1666 type = mst_text_gnu_ifunc;
1667 else
1668 type = mst_text;
1669 section = NULL;
1670 }
1671 }
1672 else
1673 addr = bound_msym.value_address ();
1674
1675 if (overlay_debugging)
1676 addr = symbol_overlayed_address (addr, section);
1677
1678 if (is_tls)
1679 {
1680 /* Skip translation if caller does not need the address. */
1681 if (address_p != NULL)
1682 *address_p = target_translate_tls_address (objfile, addr);
1683 return builtin_type (objfile)->nodebug_tls_symbol;
1684 }
1685
1686 if (address_p != NULL)
1687 *address_p = addr;
1688
1689 switch (type)
1690 {
1691 case mst_text:
1692 case mst_file_text:
1693 case mst_solib_trampoline:
1694 return builtin_type (objfile)->nodebug_text_symbol;
1695
1696 case mst_text_gnu_ifunc:
1697 return builtin_type (objfile)->nodebug_text_gnu_ifunc_symbol;
1698
1699 case mst_data:
1700 case mst_file_data:
1701 case mst_bss:
1702 case mst_file_bss:
1703 return builtin_type (objfile)->nodebug_data_symbol;
1704
1705 case mst_slot_got_plt:
1706 return builtin_type (objfile)->nodebug_got_plt_symbol;
1707
1708 default:
1709 return builtin_type (objfile)->nodebug_unknown_symbol;
1710 }
1711 }