Regenerate AArch64 opcodes files
[binutils-gdb.git] / gdb / minsyms.c
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1 /* GDB routines for manipulating the minimal symbol tables.
2 Copyright (C) 1992-2024 Free Software Foundation, Inc.
3 Contributed by Cygnus Support, using pieces from other GDB modules.
5 This file is part of GDB.
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.
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.
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/>. */
21 /* This file contains support routines for creating, manipulating, and
22 destroying minimal symbol tables.
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.
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.
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. */
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"
59 #if CXX_STD_THREAD
60 #include <mutex>
61 #endif
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]. */
71 static bool
72 msymbol_is_cold_clone (minimal_symbol *minsym)
74 const char *name = minsym->natural_name ();
75 size_t name_len = strlen (name);
76 if (name_len < 1)
77 return false;
79 const char *last = &name[name_len - 1];
80 if (*last != ']')
81 return false;
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;
89 const char *start = &found[suffix_len];
90 if (*start == ']')
91 return true;
93 if (*start != '.')
94 return false;
96 const char *p;
97 for (p = start + 1; p <= last; ++p)
99 if (*p >= '0' && *p <= '9')
100 continue;
101 break;
104 if (p == last)
105 return true;
107 return false;
110 /* See minsyms.h. */
112 bool
113 msymbol_is_function (struct objfile *objfile, minimal_symbol *minsym,
114 CORE_ADDR *func_address_p)
116 CORE_ADDR msym_addr = minsym->value_address (objfile);
118 switch (minsym->type ())
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:
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)
133 if (func_address_p != NULL)
134 *func_address_p = pc;
135 return true;
137 return false;
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 [[fallthrough]];
144 default:
145 if (func_address_p != NULL)
146 *func_address_p = msym_addr;
147 return true;
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. */
154 #define BUNCH_SIZE 127
156 struct msym_bunch
158 struct msym_bunch *next;
159 struct minimal_symbol contents[BUNCH_SIZE];
162 /* See minsyms.h. */
164 unsigned int
165 msymbol_hash_iw (const char *string)
167 unsigned int hash = 0;
169 while (*string && *string != '(')
171 string = skip_spaces (string);
172 if (*string && *string != '(')
174 hash = SYMBOL_HASH_NEXT (hash, *string);
175 ++string;
178 return hash;
181 /* See minsyms.h. */
183 unsigned int
184 msymbol_hash (const char *string)
186 unsigned int hash = 0;
188 for (; *string; ++string)
189 hash = SYMBOL_HASH_NEXT (hash, *string);
190 return hash;
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)
199 if (sym->hash_next == NULL)
201 unsigned int hash = hash_value % MINIMAL_SYMBOL_HASH_SIZE;
203 sym->hash_next = table[hash];
204 table[hash] = sym;
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)
215 if (sym->demangled_hash_next == NULL)
217 objfile->per_bfd->demangled_hash_languages.set (sym->language ());
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;
227 /* Worker object for lookup_minimal_symbol. Stores temporary results
228 while walking the symbol tables. */
230 struct found_minimal_symbols
232 /* External symbols are best. */
233 bound_minimal_symbol external_symbol;
235 /* File-local symbols are next best. */
236 bound_minimal_symbol file_symbol;
238 /* Symbols for shared library trampolines are next best. */
239 bound_minimal_symbol trampoline_symbol;
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);
249 /* See declaration above. */
251 bool
252 found_minimal_symbols::maybe_collect (const char *sfile,
253 struct objfile *objfile,
254 minimal_symbol *msymbol)
256 switch (msymbol->type ())
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)
264 file_symbol.minsym = msymbol;
265 file_symbol.objfile = objfile;
267 break;
269 case mst_solib_trampoline:
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)
277 trampoline_symbol.minsym = msymbol;
278 trampoline_symbol.objfile = objfile;
280 break;
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;
290 /* Keep looking. */
291 return false;
294 /* Walk the mangled name hash table, and pass each symbol whose name
295 matches LOOKUP_NAME according to NAMECMP to FOUND. */
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)
306 for (minimal_symbol *msymbol = table[hash];
307 msymbol != NULL;
308 msymbol = msymbol->hash_next)
310 const char *symbol_name = msymbol->linkage_name ();
312 if (namecmp (symbol_name, lookup_name) == 0
313 && found.maybe_collect (sfile, objfile, msymbol))
314 return;
318 /* Walk the demangled name hash table, and pass each symbol whose name
319 matches LOOKUP_NAME according to MATCHER to FOUND. */
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)
330 for (minimal_symbol *msymbol = table[hash];
331 msymbol != NULL;
332 msymbol = msymbol->demangled_hash_next)
334 const char *symbol_name = msymbol->search_name ();
336 if (matcher (symbol_name, lookup_name, NULL)
337 && found.maybe_collect (sfile, objfile, msymbol))
338 return;
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.
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).
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. */
362 struct bound_minimal_symbol
363 lookup_minimal_symbol (const char *name, const char *sfile,
364 struct objfile *objf)
366 found_minimal_symbols found;
368 unsigned int mangled_hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
370 auto *mangled_cmp
371 = (case_sensitivity == case_sensitive_on
372 ? strcmp
373 : strcasecmp);
375 if (sfile != NULL)
376 sfile = lbasename (sfile);
378 lookup_name_info lookup_name (name, symbol_name_match_type::FULL);
380 for (objfile *objfile : current_program_space->objfiles ())
382 if (found.external_symbol.minsym != NULL)
383 break;
385 if (objf == NULL || objf == objfile
386 || objf == objfile->separate_debug_objfile_backlink)
388 symbol_lookup_debug_printf ("lookup_minimal_symbol (%s, %s, %s)",
389 name, sfile != NULL ? sfile : "NULL",
390 objfile_debug_name (objfile));
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);
398 /* If not found, try the demangled hash table. */
399 if (found.external_symbol.minsym == NULL)
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)
405 if (!objfile->per_bfd->demangled_hash_languages.test (iter))
406 continue;
407 enum language lang = (enum language) iter;
409 unsigned int hash
410 = (lookup_name.search_name_hash (lang)
411 % MINIMAL_SYMBOL_HASH_SIZE);
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;
419 lookup_minimal_symbol_demangled (lookup_name, sfile, objfile,
420 msymbol_demangled_hash,
421 hash, match, found);
423 if (found.external_symbol.minsym != NULL)
424 break;
430 /* External symbols are best. */
431 if (found.external_symbol.minsym != NULL)
433 if (symbol_lookup_debug)
435 minimal_symbol *minsym = found.external_symbol.minsym;
437 symbol_lookup_debug_printf
438 ("lookup_minimal_symbol (...) = %s (external)",
439 host_address_to_string (minsym));
441 return found.external_symbol;
444 /* File-local symbols are next best. */
445 if (found.file_symbol.minsym != NULL)
447 if (symbol_lookup_debug)
449 minimal_symbol *minsym = found.file_symbol.minsym;
451 symbol_lookup_debug_printf
452 ("lookup_minimal_symbol (...) = %s (file-local)",
453 host_address_to_string (minsym));
455 return found.file_symbol;
458 /* Symbols for shared library trampolines are next best. */
459 if (found.trampoline_symbol.minsym != NULL)
461 if (symbol_lookup_debug)
463 minimal_symbol *minsym = found.trampoline_symbol.minsym;
465 symbol_lookup_debug_printf
466 ("lookup_minimal_symbol (...) = %s (trampoline)",
467 host_address_to_string (minsym));
470 return found.trampoline_symbol;
473 /* Not found. */
474 symbol_lookup_debug_printf ("lookup_minimal_symbol (...) = NULL");
475 return {};
478 /* See minsyms.h. */
480 struct bound_minimal_symbol
481 lookup_bound_minimal_symbol (const char *name)
483 return lookup_minimal_symbol (name, NULL, NULL);
486 /* See gdbsupport/symbol.h. */
489 find_minimal_symbol_address (const char *name, CORE_ADDR *addr,
490 struct objfile *objfile)
492 struct bound_minimal_symbol sym
493 = lookup_minimal_symbol (name, NULL, objfile);
495 if (sym.minsym != NULL)
496 *addr = sym.value_address ();
498 return sym.minsym == NULL;
501 /* Get the lookup name form best suitable for linkage name
502 matching. */
504 static const char *
505 linkage_name_str (const lookup_name_info &lookup_name)
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 ();
517 return lookup_name.c_str ();
520 /* See minsyms.h. */
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)
527 /* The first pass is over the ordinary hash table. */
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);
536 for (minimal_symbol *iter = objf->per_bfd->msymbol_hash[hash];
537 iter != NULL;
538 iter = iter->hash_next)
540 if (mangled_cmp (iter->linkage_name (), name) == 0)
541 if (callback (iter))
542 return;
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)
551 if (!objf->per_bfd->demangled_hash_languages.test (liter))
552 continue;
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);
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;
570 /* See minsyms.h. */
572 bound_minimal_symbol
573 lookup_minimal_symbol_linkage (const char *name, struct objfile *objf)
575 unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
577 for (objfile *objfile : objf->separate_debug_objfiles ())
579 for (minimal_symbol *msymbol = objfile->per_bfd->msymbol_hash[hash];
580 msymbol != NULL;
581 msymbol = msymbol->hash_next)
583 if (strcmp (msymbol->linkage_name (), name) == 0
584 && (msymbol->type () == mst_data
585 || msymbol->type () == mst_bss))
586 return {msymbol, objfile};
590 return {};
593 /* See minsyms.h. */
595 struct bound_minimal_symbol
596 lookup_minimal_symbol_linkage (const char *name, bool only_main)
598 for (objfile *objfile : current_program_space->objfiles ())
600 if (objfile->separate_debug_objfile_backlink != nullptr)
601 continue;
603 if (only_main && (objfile->flags & OBJF_MAINLINE) == 0)
604 continue;
606 bound_minimal_symbol minsym = lookup_minimal_symbol_linkage (name,
607 objfile);
608 if (minsym.minsym != nullptr)
609 return minsym;
612 return {};
615 /* See minsyms.h. */
617 struct bound_minimal_symbol
618 lookup_minimal_symbol_text (const char *name, struct objfile *objf)
620 struct minimal_symbol *msymbol;
621 struct bound_minimal_symbol found_symbol;
622 struct bound_minimal_symbol found_file_symbol;
624 unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
626 auto search = [&] (struct objfile *objfile)
628 for (msymbol = objfile->per_bfd->msymbol_hash[hash];
629 msymbol != NULL && found_symbol.minsym == NULL;
630 msymbol = msymbol->hash_next)
632 if (strcmp (msymbol->linkage_name (), name) == 0 &&
633 (msymbol->type () == mst_text
634 || msymbol->type () == mst_text_gnu_ifunc
635 || msymbol->type () == mst_file_text))
637 switch (msymbol->type ())
639 case mst_file_text:
640 found_file_symbol.minsym = msymbol;
641 found_file_symbol.objfile = objfile;
642 break;
643 default:
644 found_symbol.minsym = msymbol;
645 found_symbol.objfile = objfile;
646 break;
652 if (objf == nullptr)
654 for (objfile *objfile : current_program_space->objfiles ())
656 if (found_symbol.minsym != NULL)
657 break;
658 search (objfile);
661 else
663 for (objfile *objfile : objf->separate_debug_objfiles ())
665 if (found_symbol.minsym != NULL)
666 break;
667 search (objfile);
671 /* External symbols are best. */
672 if (found_symbol.minsym)
673 return found_symbol;
675 /* File-local symbols are next best. */
676 return found_file_symbol;
679 /* See minsyms.h. */
681 struct minimal_symbol *
682 lookup_minimal_symbol_by_pc_name (CORE_ADDR pc, const char *name,
683 struct objfile *objf)
685 struct minimal_symbol *msymbol;
687 unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
689 for (objfile *objfile : current_program_space->objfiles ())
691 if (objf == NULL || objf == objfile
692 || objf == objfile->separate_debug_objfile_backlink)
694 for (msymbol = objfile->per_bfd->msymbol_hash[hash];
695 msymbol != NULL;
696 msymbol = msymbol->hash_next)
698 if (msymbol->value_address (objfile) == pc
699 && strcmp (msymbol->linkage_name (), name) == 0)
700 return msymbol;
705 return NULL;
708 /* A helper function that makes *PC section-relative. This searches
709 the sections of OBJFILE and if *PC is in a section, it subtracts
710 the section offset, stores the result into UNREL_ADDR, and returns
711 true. Otherwise it returns false. */
713 static int
714 frob_address (struct objfile *objfile, CORE_ADDR pc,
715 unrelocated_addr *unrel_addr)
717 for (obj_section *iter : objfile->sections ())
719 if (iter->contains (pc))
721 *unrel_addr = unrelocated_addr (pc - iter->offset ());
722 return 1;
726 return 0;
729 /* Helper for lookup_minimal_symbol_by_pc_section. Convert a
730 lookup_msym_prefer to a minimal_symbol_type. */
732 static minimal_symbol_type
733 msym_prefer_to_msym_type (lookup_msym_prefer prefer)
735 switch (prefer)
737 case lookup_msym_prefer::TEXT:
738 return mst_text;
739 case lookup_msym_prefer::TRAMPOLINE:
740 return mst_solib_trampoline;
741 case lookup_msym_prefer::GNU_IFUNC:
742 return mst_text_gnu_ifunc;
745 /* Assert here instead of in a default switch case above so that
746 -Wswitch warns if a new enumerator is added. */
747 gdb_assert_not_reached ("unhandled lookup_msym_prefer");
750 /* See minsyms.h.
752 Note that we need to look through ALL the minimal symbol tables
753 before deciding on the symbol that comes closest to the specified PC.
754 This is because objfiles can overlap, for example objfile A has .text
755 at 0x100 and .data at 0x40000 and objfile B has .text at 0x234 and
756 .data at 0x40048. */
758 bound_minimal_symbol
759 lookup_minimal_symbol_by_pc_section (CORE_ADDR pc_in, struct obj_section *section,
760 lookup_msym_prefer prefer,
761 bound_minimal_symbol *previous)
763 int lo;
764 int hi;
765 int newobj;
766 struct minimal_symbol *msymbol;
767 struct minimal_symbol *best_symbol = NULL;
768 struct objfile *best_objfile = NULL;
769 struct bound_minimal_symbol result;
771 if (previous != nullptr)
773 previous->minsym = nullptr;
774 previous->objfile = nullptr;
777 if (section == NULL)
779 section = find_pc_section (pc_in);
780 if (section == NULL)
781 return {};
784 minimal_symbol_type want_type = msym_prefer_to_msym_type (prefer);
786 /* We can not require the symbol found to be in section, because
787 e.g. IRIX 6.5 mdebug relies on this code returning an absolute
788 symbol - but find_pc_section won't return an absolute section and
789 hence the code below would skip over absolute symbols. We can
790 still take advantage of the call to find_pc_section, though - the
791 object file still must match. In case we have separate debug
792 files, search both the file and its separate debug file. There's
793 no telling which one will have the minimal symbols. */
795 gdb_assert (section != NULL);
797 for (objfile *objfile : section->objfile->separate_debug_objfiles ())
799 CORE_ADDR pc = pc_in;
801 /* If this objfile has a minimal symbol table, go search it
802 using a binary search. */
804 if (objfile->per_bfd->minimal_symbol_count > 0)
806 int best_zero_sized = -1;
808 msymbol = objfile->per_bfd->msymbols.get ();
809 lo = 0;
810 hi = objfile->per_bfd->minimal_symbol_count - 1;
812 /* This code assumes that the minimal symbols are sorted by
813 ascending address values. If the pc value is greater than or
814 equal to the first symbol's address, then some symbol in this
815 minimal symbol table is a suitable candidate for being the
816 "best" symbol. This includes the last real symbol, for cases
817 where the pc value is larger than any address in this vector.
819 By iterating until the address associated with the current
820 hi index (the endpoint of the test interval) is less than
821 or equal to the desired pc value, we accomplish two things:
822 (1) the case where the pc value is larger than any minimal
823 symbol address is trivially solved, (2) the address associated
824 with the hi index is always the one we want when the iteration
825 terminates. In essence, we are iterating the test interval
826 down until the pc value is pushed out of it from the high end.
828 Warning: this code is trickier than it would appear at first. */
830 unrelocated_addr unrel_pc;
831 if (frob_address (objfile, pc, &unrel_pc)
832 && unrel_pc >= msymbol[lo].unrelocated_address ())
834 while (msymbol[hi].unrelocated_address () > unrel_pc)
836 /* pc is still strictly less than highest address. */
837 /* Note "new" will always be >= lo. */
838 newobj = (lo + hi) / 2;
839 if ((msymbol[newobj].unrelocated_address () >= unrel_pc)
840 || (lo == newobj))
842 hi = newobj;
844 else
846 lo = newobj;
850 /* If we have multiple symbols at the same address, we want
851 hi to point to the last one. That way we can find the
852 right symbol if it has an index greater than hi. */
853 while (hi < objfile->per_bfd->minimal_symbol_count - 1
854 && (msymbol[hi].unrelocated_address ()
855 == msymbol[hi + 1].unrelocated_address ()))
856 hi++;
858 /* Skip various undesirable symbols. */
859 while (hi >= 0)
861 /* Skip any absolute symbols. This is apparently
862 what adb and dbx do, and is needed for the CM-5.
863 There are two known possible problems: (1) on
864 ELF, apparently end, edata, etc. are absolute.
865 Not sure ignoring them here is a big deal, but if
866 we want to use them, the fix would go in
867 elfread.c. (2) I think shared library entry
868 points on the NeXT are absolute. If we want
869 special handling for this it probably should be
870 triggered by a special mst_abs_or_lib or some
871 such. */
873 if (msymbol[hi].type () == mst_abs)
875 hi--;
876 continue;
879 /* If SECTION was specified, skip any symbol from
880 wrong section. */
881 if (section
882 /* Some types of debug info, such as COFF,
883 don't fill the bfd_section member, so don't
884 throw away symbols on those platforms. */
885 && msymbol[hi].obj_section (objfile) != nullptr
886 && (!matching_obj_sections
887 (msymbol[hi].obj_section (objfile),
888 section)))
890 hi--;
891 continue;
894 /* If we are looking for a trampoline and this is a
895 text symbol, or the other way around, check the
896 preceding symbol too. If they are otherwise
897 identical prefer that one. */
898 if (hi > 0
899 && msymbol[hi].type () != want_type
900 && msymbol[hi - 1].type () == want_type
901 && (msymbol[hi].size () == msymbol[hi - 1].size ())
902 && (msymbol[hi].unrelocated_address ()
903 == msymbol[hi - 1].unrelocated_address ())
904 && (msymbol[hi].obj_section (objfile)
905 == msymbol[hi - 1].obj_section (objfile)))
907 hi--;
908 continue;
911 /* If the minimal symbol has a zero size, save it
912 but keep scanning backwards looking for one with
913 a non-zero size. A zero size may mean that the
914 symbol isn't an object or function (e.g. a
915 label), or it may just mean that the size was not
916 specified. */
917 if (msymbol[hi].size () == 0)
919 if (best_zero_sized == -1)
920 best_zero_sized = hi;
921 hi--;
922 continue;
925 /* If we are past the end of the current symbol, try
926 the previous symbol if it has a larger overlapping
927 size. This happens on i686-pc-linux-gnu with glibc;
928 the nocancel variants of system calls are inside
929 the cancellable variants, but both have sizes. */
930 if (hi > 0
931 && msymbol[hi].size () != 0
932 && unrel_pc >= msymbol[hi].unrelocated_end_address ()
933 && unrel_pc < msymbol[hi - 1].unrelocated_end_address ())
935 hi--;
936 continue;
939 /* Otherwise, this symbol must be as good as we're going
940 to get. */
941 break;
944 /* If HI has a zero size, and best_zero_sized is set,
945 then we had two or more zero-sized symbols; prefer
946 the first one we found (which may have a higher
947 address). Also, if we ran off the end, be sure
948 to back up. */
949 if (best_zero_sized != -1
950 && (hi < 0 || msymbol[hi].size () == 0))
951 hi = best_zero_sized;
953 /* If the minimal symbol has a non-zero size, and this
954 PC appears to be outside the symbol's contents, then
955 refuse to use this symbol. If we found a zero-sized
956 symbol with an address greater than this symbol's,
957 use that instead. We assume that if symbols have
958 specified sizes, they do not overlap. */
960 if (hi >= 0
961 && msymbol[hi].size () != 0
962 && unrel_pc >= msymbol[hi].unrelocated_end_address ())
964 if (best_zero_sized != -1)
965 hi = best_zero_sized;
966 else
968 /* If needed record this symbol as the closest
969 previous symbol. */
970 if (previous != nullptr)
972 if (previous->minsym == nullptr
973 || (msymbol[hi].unrelocated_address ()
974 > previous->minsym->unrelocated_address ()))
976 previous->minsym = &msymbol[hi];
977 previous->objfile = objfile;
980 /* Go on to the next object file. */
981 continue;
985 /* The minimal symbol indexed by hi now is the best one in this
986 objfile's minimal symbol table. See if it is the best one
987 overall. */
989 if (hi >= 0
990 && ((best_symbol == NULL) ||
991 (best_symbol->unrelocated_address () <
992 msymbol[hi].unrelocated_address ())))
994 best_symbol = &msymbol[hi];
995 best_objfile = objfile;
1001 result.minsym = best_symbol;
1002 result.objfile = best_objfile;
1003 return result;
1006 /* See minsyms.h. */
1008 struct bound_minimal_symbol
1009 lookup_minimal_symbol_by_pc (CORE_ADDR pc)
1011 return lookup_minimal_symbol_by_pc_section (pc, NULL);
1014 /* Return non-zero iff PC is in an STT_GNU_IFUNC function resolver. */
1016 bool
1017 in_gnu_ifunc_stub (CORE_ADDR pc)
1019 bound_minimal_symbol msymbol
1020 = lookup_minimal_symbol_by_pc_section (pc, NULL,
1021 lookup_msym_prefer::GNU_IFUNC);
1022 return msymbol.minsym && msymbol.minsym->type () == mst_text_gnu_ifunc;
1025 /* See elf_gnu_ifunc_resolve_addr for its real implementation. */
1027 static CORE_ADDR
1028 stub_gnu_ifunc_resolve_addr (struct gdbarch *gdbarch, CORE_ADDR pc)
1030 error (_("GDB cannot resolve STT_GNU_IFUNC symbol at address %s without "
1031 "the ELF support compiled in."),
1032 paddress (gdbarch, pc));
1035 /* See elf_gnu_ifunc_resolve_name for its real implementation. */
1037 static bool
1038 stub_gnu_ifunc_resolve_name (const char *function_name,
1039 CORE_ADDR *function_address_p)
1041 error (_("GDB cannot resolve STT_GNU_IFUNC symbol \"%s\" without "
1042 "the ELF support compiled in."),
1043 function_name);
1046 /* See elf_gnu_ifunc_resolver_stop for its real implementation. */
1048 static void
1049 stub_gnu_ifunc_resolver_stop (code_breakpoint *b)
1051 internal_error (_("elf_gnu_ifunc_resolver_stop cannot be reached."));
1054 /* See elf_gnu_ifunc_resolver_return_stop for its real implementation. */
1056 static void
1057 stub_gnu_ifunc_resolver_return_stop (code_breakpoint *b)
1059 internal_error (_("elf_gnu_ifunc_resolver_return_stop cannot be reached."));
1062 /* See elf_gnu_ifunc_fns for its real implementation. */
1064 static const struct gnu_ifunc_fns stub_gnu_ifunc_fns =
1066 stub_gnu_ifunc_resolve_addr,
1067 stub_gnu_ifunc_resolve_name,
1068 stub_gnu_ifunc_resolver_stop,
1069 stub_gnu_ifunc_resolver_return_stop,
1072 /* A placeholder for &elf_gnu_ifunc_fns. */
1074 const struct gnu_ifunc_fns *gnu_ifunc_fns_p = &stub_gnu_ifunc_fns;
1078 /* Return leading symbol character for a BFD. If BFD is NULL,
1079 return the leading symbol character from the main objfile. */
1081 static int
1082 get_symbol_leading_char (bfd *abfd)
1084 if (abfd != NULL)
1085 return bfd_get_symbol_leading_char (abfd);
1086 if (current_program_space->symfile_object_file != NULL)
1088 objfile *objf = current_program_space->symfile_object_file;
1089 if (objf->obfd != NULL)
1090 return bfd_get_symbol_leading_char (objf->obfd.get ());
1092 return 0;
1095 /* See minsyms.h. */
1097 minimal_symbol_reader::minimal_symbol_reader (struct objfile *obj)
1098 : m_objfile (obj),
1099 m_msym_bunch (NULL),
1100 /* Note that presetting m_msym_bunch_index to BUNCH_SIZE causes the
1101 first call to save a minimal symbol to allocate the memory for
1102 the first bunch. */
1103 m_msym_bunch_index (BUNCH_SIZE),
1104 m_msym_count (0)
1108 /* Discard the currently collected minimal symbols, if any. If we wish
1109 to save them for later use, we must have already copied them somewhere
1110 else before calling this function. */
1112 minimal_symbol_reader::~minimal_symbol_reader ()
1114 struct msym_bunch *next;
1116 while (m_msym_bunch != NULL)
1118 next = m_msym_bunch->next;
1119 xfree (m_msym_bunch);
1120 m_msym_bunch = next;
1124 /* See minsyms.h. */
1126 void
1127 minimal_symbol_reader::record (const char *name, unrelocated_addr address,
1128 enum minimal_symbol_type ms_type)
1130 int section;
1132 switch (ms_type)
1134 case mst_text:
1135 case mst_text_gnu_ifunc:
1136 case mst_file_text:
1137 case mst_solib_trampoline:
1138 section = SECT_OFF_TEXT (m_objfile);
1139 break;
1140 case mst_data:
1141 case mst_data_gnu_ifunc:
1142 case mst_file_data:
1143 section = SECT_OFF_DATA (m_objfile);
1144 break;
1145 case mst_bss:
1146 case mst_file_bss:
1147 section = SECT_OFF_BSS (m_objfile);
1148 break;
1149 default:
1150 section = -1;
1153 record_with_info (name, address, ms_type, section);
1156 /* Convert an enumerator of type minimal_symbol_type to its string
1157 representation. */
1159 static const char *
1160 mst_str (minimal_symbol_type t)
1162 #define MST_TO_STR(x) case x: return #x;
1163 switch (t)
1165 MST_TO_STR (mst_unknown);
1166 MST_TO_STR (mst_text);
1167 MST_TO_STR (mst_text_gnu_ifunc);
1168 MST_TO_STR (mst_slot_got_plt);
1169 MST_TO_STR (mst_data);
1170 MST_TO_STR (mst_bss);
1171 MST_TO_STR (mst_abs);
1172 MST_TO_STR (mst_solib_trampoline);
1173 MST_TO_STR (mst_file_text);
1174 MST_TO_STR (mst_file_data);
1175 MST_TO_STR (mst_file_bss);
1177 default:
1178 return "mst_???";
1180 #undef MST_TO_STR
1183 /* See minsyms.h. */
1185 struct minimal_symbol *
1186 minimal_symbol_reader::record_full (std::string_view name,
1187 bool copy_name, unrelocated_addr address,
1188 enum minimal_symbol_type ms_type,
1189 int section)
1191 struct msym_bunch *newobj;
1192 struct minimal_symbol *msymbol;
1194 /* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into
1195 the minimal symbols, because if there is also another symbol
1196 at the same address (e.g. the first function of the file),
1197 lookup_minimal_symbol_by_pc would have no way of getting the
1198 right one. */
1199 if (ms_type == mst_file_text && name[0] == 'g'
1200 && (name == GCC_COMPILED_FLAG_SYMBOL
1201 || name == GCC2_COMPILED_FLAG_SYMBOL))
1202 return (NULL);
1204 /* It's safe to strip the leading char here once, since the name
1205 is also stored stripped in the minimal symbol table. */
1206 if (name[0] == get_symbol_leading_char (m_objfile->obfd.get ()))
1207 name = name.substr (1);
1209 if (ms_type == mst_file_text && startswith (name, "__gnu_compiled"))
1210 return (NULL);
1212 symtab_create_debug_printf_v ("recording minsym: %-21s %18s %4d %.*s",
1213 mst_str (ms_type),
1214 hex_string (LONGEST (address)),
1215 section, (int) name.size (), name.data ());
1217 if (m_msym_bunch_index == BUNCH_SIZE)
1219 newobj = XCNEW (struct msym_bunch);
1220 m_msym_bunch_index = 0;
1221 newobj->next = m_msym_bunch;
1222 m_msym_bunch = newobj;
1224 msymbol = &m_msym_bunch->contents[m_msym_bunch_index];
1225 msymbol->set_language (language_unknown,
1226 &m_objfile->per_bfd->storage_obstack);
1228 if (copy_name)
1229 msymbol->m_name = obstack_strndup (&m_objfile->per_bfd->storage_obstack,
1230 name.data (), name.size ());
1231 else
1232 msymbol->m_name = name.data ();
1234 msymbol->set_unrelocated_address (address);
1235 msymbol->set_section_index (section);
1237 msymbol->set_type (ms_type);
1239 /* If we already read minimal symbols for this objfile, then don't
1240 ever allocate a new one. */
1241 if (!m_objfile->per_bfd->minsyms_read)
1243 m_msym_bunch_index++;
1244 m_objfile->per_bfd->n_minsyms++;
1246 m_msym_count++;
1247 return msymbol;
1250 /* Compare two minimal symbols by address and return true if FN1's address
1251 is less than FN2's, so that we sort into unsigned numeric order.
1252 Within groups with the same address, sort by name. */
1254 static inline bool
1255 minimal_symbol_is_less_than (const minimal_symbol &fn1,
1256 const minimal_symbol &fn2)
1258 if ((&fn1)->unrelocated_address () < (&fn2)->unrelocated_address ())
1260 return true; /* addr 1 is less than addr 2. */
1262 else if ((&fn1)->unrelocated_address () > (&fn2)->unrelocated_address ())
1264 return false; /* addr 1 is greater than addr 2. */
1266 else
1267 /* addrs are equal: sort by name */
1269 const char *name1 = fn1.linkage_name ();
1270 const char *name2 = fn2.linkage_name ();
1272 if (name1 && name2) /* both have names */
1273 return strcmp (name1, name2) < 0;
1274 else if (name2)
1275 return true; /* fn1 has no name, so it is "less". */
1276 else if (name1) /* fn2 has no name, so it is "less". */
1277 return false;
1278 else
1279 return false; /* Neither has a name, so they're equal. */
1283 /* Compact duplicate entries out of a minimal symbol table by walking
1284 through the table and compacting out entries with duplicate addresses
1285 and matching names. Return the number of entries remaining.
1287 On entry, the table resides between msymbol[0] and msymbol[mcount].
1288 On exit, it resides between msymbol[0] and msymbol[result_count].
1290 When files contain multiple sources of symbol information, it is
1291 possible for the minimal symbol table to contain many duplicate entries.
1292 As an example, SVR4 systems use ELF formatted object files, which
1293 usually contain at least two different types of symbol tables (a
1294 standard ELF one and a smaller dynamic linking table), as well as
1295 DWARF debugging information for files compiled with -g.
1297 Without compacting, the minimal symbol table for gdb itself contains
1298 over a 1000 duplicates, about a third of the total table size. Aside
1299 from the potential trap of not noticing that two successive entries
1300 identify the same location, this duplication impacts the time required
1301 to linearly scan the table, which is done in a number of places. So we
1302 just do one linear scan here and toss out the duplicates.
1304 Since the different sources of information for each symbol may
1305 have different levels of "completeness", we may have duplicates
1306 that have one entry with type "mst_unknown" and the other with a
1307 known type. So if the one we are leaving alone has type mst_unknown,
1308 overwrite its type with the type from the one we are compacting out. */
1310 static int
1311 compact_minimal_symbols (struct minimal_symbol *msymbol, int mcount,
1312 struct objfile *objfile)
1314 struct minimal_symbol *copyfrom;
1315 struct minimal_symbol *copyto;
1317 if (mcount > 0)
1319 copyfrom = copyto = msymbol;
1320 while (copyfrom < msymbol + mcount - 1)
1322 if (copyfrom->unrelocated_address ()
1323 == (copyfrom + 1)->unrelocated_address ()
1324 && (copyfrom->section_index ()
1325 == (copyfrom + 1)->section_index ())
1326 && strcmp (copyfrom->linkage_name (),
1327 (copyfrom + 1)->linkage_name ()) == 0)
1329 if ((copyfrom + 1)->type () == mst_unknown)
1330 (copyfrom + 1)->set_type (copyfrom->type ());
1332 copyfrom++;
1334 else
1335 *copyto++ = *copyfrom++;
1337 *copyto++ = *copyfrom++;
1338 mcount = copyto - msymbol;
1340 return (mcount);
1343 static void
1344 clear_minimal_symbol_hash_tables (struct objfile *objfile)
1346 for (size_t i = 0; i < MINIMAL_SYMBOL_HASH_SIZE; i++)
1348 objfile->per_bfd->msymbol_hash[i] = 0;
1349 objfile->per_bfd->msymbol_demangled_hash[i] = 0;
1353 /* This struct is used to store values we compute for msymbols on the
1354 background threads but don't need to keep around long term. */
1355 struct computed_hash_values
1357 /* Length of the linkage_name of the symbol. */
1358 size_t name_length;
1359 /* Hash code (using fast_hash) of the linkage_name. */
1360 hashval_t mangled_name_hash;
1361 /* The msymbol_hash of the linkage_name. */
1362 unsigned int minsym_hash;
1363 /* The msymbol_hash of the search_name. */
1364 unsigned int minsym_demangled_hash;
1367 /* Build (or rebuild) the minimal symbol hash tables. This is necessary
1368 after compacting or sorting the table since the entries move around
1369 thus causing the internal minimal_symbol pointers to become jumbled. */
1371 static void
1372 build_minimal_symbol_hash_tables
1373 (struct objfile *objfile,
1374 const std::vector<computed_hash_values>& hash_values)
1376 int i;
1377 struct minimal_symbol *msym;
1379 /* (Re)insert the actual entries. */
1380 int mcount = objfile->per_bfd->minimal_symbol_count;
1381 for ((i = 0,
1382 msym = objfile->per_bfd->msymbols.get ());
1383 i < mcount;
1384 i++, msym++)
1386 msym->hash_next = 0;
1387 add_minsym_to_hash_table (msym, objfile->per_bfd->msymbol_hash,
1388 hash_values[i].minsym_hash);
1390 msym->demangled_hash_next = 0;
1391 if (msym->search_name () != msym->linkage_name ())
1392 add_minsym_to_demangled_hash_table
1393 (msym, objfile, hash_values[i].minsym_demangled_hash);
1397 /* Add the minimal symbols in the existing bunches to the objfile's official
1398 minimal symbol table. In most cases there is no minimal symbol table yet
1399 for this objfile, and the existing bunches are used to create one. Once
1400 in a while (for shared libraries for example), we add symbols (e.g. common
1401 symbols) to an existing objfile. */
1403 void
1404 minimal_symbol_reader::install ()
1406 int mcount;
1407 struct msym_bunch *bunch;
1408 struct minimal_symbol *msymbols;
1409 int alloc_count;
1411 if (m_objfile->per_bfd->minsyms_read)
1412 return;
1414 if (m_msym_count > 0)
1416 symtab_create_debug_printf ("installing %d minimal symbols of objfile %s",
1417 m_msym_count, objfile_name (m_objfile));
1419 /* Allocate enough space, into which we will gather the bunches
1420 of new and existing minimal symbols, sort them, and then
1421 compact out the duplicate entries. Once we have a final
1422 table, we will give back the excess space. */
1424 alloc_count = m_msym_count + m_objfile->per_bfd->minimal_symbol_count;
1425 gdb::unique_xmalloc_ptr<minimal_symbol>
1426 msym_holder (XNEWVEC (minimal_symbol, alloc_count));
1427 msymbols = msym_holder.get ();
1429 /* Copy in the existing minimal symbols, if there are any. */
1431 if (m_objfile->per_bfd->minimal_symbol_count)
1432 memcpy (msymbols, m_objfile->per_bfd->msymbols.get (),
1433 m_objfile->per_bfd->minimal_symbol_count
1434 * sizeof (struct minimal_symbol));
1436 /* Walk through the list of minimal symbol bunches, adding each symbol
1437 to the new contiguous array of symbols. Note that we start with the
1438 current, possibly partially filled bunch (thus we use the current
1439 msym_bunch_index for the first bunch we copy over), and thereafter
1440 each bunch is full. */
1442 mcount = m_objfile->per_bfd->minimal_symbol_count;
1444 for (bunch = m_msym_bunch; bunch != NULL; bunch = bunch->next)
1446 memcpy (&msymbols[mcount], &bunch->contents[0],
1447 m_msym_bunch_index * sizeof (struct minimal_symbol));
1448 mcount += m_msym_bunch_index;
1449 m_msym_bunch_index = BUNCH_SIZE;
1452 /* Sort the minimal symbols by address. */
1454 std::sort (msymbols, msymbols + mcount, minimal_symbol_is_less_than);
1456 /* Compact out any duplicates, and free up whatever space we are
1457 no longer using. */
1459 mcount = compact_minimal_symbols (msymbols, mcount, m_objfile);
1460 msym_holder.reset (XRESIZEVEC (struct minimal_symbol,
1461 msym_holder.release (),
1462 mcount));
1464 /* Attach the minimal symbol table to the specified objfile.
1465 The strings themselves are also located in the storage_obstack
1466 of this objfile. */
1468 if (m_objfile->per_bfd->minimal_symbol_count != 0)
1469 clear_minimal_symbol_hash_tables (m_objfile);
1471 m_objfile->per_bfd->minimal_symbol_count = mcount;
1472 m_objfile->per_bfd->msymbols = std::move (msym_holder);
1474 #if CXX_STD_THREAD
1475 /* Mutex that is used when modifying or accessing the demangled
1476 hash table. */
1477 std::mutex demangled_mutex;
1478 #endif
1480 std::vector<computed_hash_values> hash_values (mcount);
1482 msymbols = m_objfile->per_bfd->msymbols.get ();
1483 /* Arbitrarily require at least 10 elements in a thread. */
1484 gdb::parallel_for_each (10, &msymbols[0], &msymbols[mcount],
1485 [&] (minimal_symbol *start, minimal_symbol *end)
1487 for (minimal_symbol *msym = start; msym < end; ++msym)
1489 size_t idx = msym - msymbols;
1490 hash_values[idx].name_length = strlen (msym->linkage_name ());
1491 if (!msym->name_set)
1493 /* This will be freed later, by compute_and_set_names. */
1494 gdb::unique_xmalloc_ptr<char> demangled_name
1495 = symbol_find_demangled_name (msym, msym->linkage_name ());
1496 msym->set_demangled_name
1497 (demangled_name.release (),
1498 &m_objfile->per_bfd->storage_obstack);
1499 msym->name_set = 1;
1501 /* This mangled_name_hash computation has to be outside of
1502 the name_set check, or compute_and_set_names below will
1503 be called with an invalid hash value. */
1504 hash_values[idx].mangled_name_hash
1505 = fast_hash (msym->linkage_name (),
1506 hash_values[idx].name_length);
1507 hash_values[idx].minsym_hash
1508 = msymbol_hash (msym->linkage_name ());
1509 /* We only use this hash code if the search name differs
1510 from the linkage name. See the code in
1511 build_minimal_symbol_hash_tables. */
1512 if (msym->search_name () != msym->linkage_name ())
1513 hash_values[idx].minsym_demangled_hash
1514 = search_name_hash (msym->language (), msym->search_name ());
1517 /* To limit how long we hold the lock, we only acquire it here
1518 and not while we demangle the names above. */
1519 #if CXX_STD_THREAD
1520 std::lock_guard<std::mutex> guard (demangled_mutex);
1521 #endif
1522 for (minimal_symbol *msym = start; msym < end; ++msym)
1524 size_t idx = msym - msymbols;
1525 msym->compute_and_set_names
1526 (std::string_view (msym->linkage_name (),
1527 hash_values[idx].name_length),
1528 false,
1529 m_objfile->per_bfd,
1530 hash_values[idx].mangled_name_hash);
1535 build_minimal_symbol_hash_tables (m_objfile, hash_values);
1539 /* Check if PC is in a shared library trampoline code stub.
1540 Return minimal symbol for the trampoline entry or NULL if PC is not
1541 in a trampoline code stub. */
1543 static struct minimal_symbol *
1544 lookup_solib_trampoline_symbol_by_pc (CORE_ADDR pc)
1546 bound_minimal_symbol msymbol
1547 = lookup_minimal_symbol_by_pc_section (pc, NULL,
1548 lookup_msym_prefer::TRAMPOLINE);
1550 if (msymbol.minsym != NULL
1551 && msymbol.minsym->type () == mst_solib_trampoline)
1552 return msymbol.minsym;
1553 return NULL;
1556 /* If PC is in a shared library trampoline code stub, return the
1557 address of the `real' function belonging to the stub.
1558 Return 0 if PC is not in a trampoline code stub or if the real
1559 function is not found in the minimal symbol table.
1561 We may fail to find the right function if a function with the
1562 same name is defined in more than one shared library, but this
1563 is considered bad programming style. We could return 0 if we find
1564 a duplicate function in case this matters someday. */
1566 CORE_ADDR
1567 find_solib_trampoline_target (const frame_info_ptr &frame, CORE_ADDR pc)
1569 struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc);
1571 if (tsymbol != NULL)
1573 for (objfile *objfile : current_program_space->objfiles ())
1575 for (minimal_symbol *msymbol : objfile->msymbols ())
1577 /* Also handle minimal symbols pointing to function
1578 descriptors. */
1579 if ((msymbol->type () == mst_text
1580 || msymbol->type () == mst_text_gnu_ifunc
1581 || msymbol->type () == mst_data
1582 || msymbol->type () == mst_data_gnu_ifunc)
1583 && strcmp (msymbol->linkage_name (),
1584 tsymbol->linkage_name ()) == 0)
1586 CORE_ADDR func;
1588 /* Ignore data symbols that are not function
1589 descriptors. */
1590 if (msymbol_is_function (objfile, msymbol, &func))
1591 return func;
1596 return 0;
1599 /* See minsyms.h. */
1601 CORE_ADDR
1602 minimal_symbol_upper_bound (struct bound_minimal_symbol minsym)
1604 short section;
1605 struct obj_section *obj_section;
1606 CORE_ADDR result;
1607 struct minimal_symbol *iter, *msymbol;
1609 gdb_assert (minsym.minsym != NULL);
1611 /* If the minimal symbol has a size, use it. Otherwise use the
1612 lesser of the next minimal symbol in the same section, or the end
1613 of the section, as the end of the function. */
1615 if (minsym.minsym->size () != 0)
1616 return minsym.value_address () + minsym.minsym->size ();
1618 /* Step over other symbols at this same address, and symbols in
1619 other sections, to find the next symbol in this section with a
1620 different address. */
1622 struct minimal_symbol *past_the_end
1623 = (minsym.objfile->per_bfd->msymbols.get ()
1624 + minsym.objfile->per_bfd->minimal_symbol_count);
1625 msymbol = minsym.minsym;
1626 section = msymbol->section_index ();
1627 for (iter = msymbol + 1; iter != past_the_end; ++iter)
1629 if ((iter->unrelocated_address ()
1630 != msymbol->unrelocated_address ())
1631 && iter->section_index () == section)
1632 break;
1635 obj_section = minsym.obj_section ();
1636 if (iter != past_the_end
1637 && (iter->value_address (minsym.objfile)
1638 < obj_section->endaddr ()))
1639 result = iter->value_address (minsym.objfile);
1640 else
1641 /* We got the start address from the last msymbol in the objfile.
1642 So the end address is the end of the section. */
1643 result = obj_section->endaddr ();
1645 return result;
1648 /* See minsyms.h. */
1650 type *
1651 find_minsym_type_and_address (minimal_symbol *msymbol,
1652 struct objfile *objfile,
1653 CORE_ADDR *address_p)
1655 bound_minimal_symbol bound_msym = {msymbol, objfile};
1656 struct obj_section *section = msymbol->obj_section (objfile);
1657 enum minimal_symbol_type type = msymbol->type ();
1659 bool is_tls = (section != NULL
1660 && section->the_bfd_section->flags & SEC_THREAD_LOCAL);
1662 /* The minimal symbol might point to a function descriptor;
1663 resolve it to the actual code address instead. */
1664 CORE_ADDR addr;
1665 if (is_tls)
1667 /* Addresses of TLS symbols are really offsets into a
1668 per-objfile/per-thread storage block. */
1669 addr = CORE_ADDR (bound_msym.minsym->unrelocated_address ());
1671 else if (msymbol_is_function (objfile, msymbol, &addr))
1673 if (addr != bound_msym.value_address ())
1675 /* This means we resolved a function descriptor, and we now
1676 have an address for a code/text symbol instead of a data
1677 symbol. */
1678 if (msymbol->type () == mst_data_gnu_ifunc)
1679 type = mst_text_gnu_ifunc;
1680 else
1681 type = mst_text;
1682 section = NULL;
1685 else
1686 addr = bound_msym.value_address ();
1688 if (overlay_debugging)
1689 addr = symbol_overlayed_address (addr, section);
1691 if (is_tls)
1693 /* Skip translation if caller does not need the address. */
1694 if (address_p != NULL)
1695 *address_p = target_translate_tls_address (objfile, addr);
1696 return builtin_type (objfile)->nodebug_tls_symbol;
1699 if (address_p != NULL)
1700 *address_p = addr;
1702 switch (type)
1704 case mst_text:
1705 case mst_file_text:
1706 case mst_solib_trampoline:
1707 return builtin_type (objfile)->nodebug_text_symbol;
1709 case mst_text_gnu_ifunc:
1710 return builtin_type (objfile)->nodebug_text_gnu_ifunc_symbol;
1712 case mst_data:
1713 case mst_file_data:
1714 case mst_bss:
1715 case mst_file_bss:
1716 return builtin_type (objfile)->nodebug_data_symbol;
1718 case mst_slot_got_plt:
1719 return builtin_type (objfile)->nodebug_got_plt_symbol;
1721 default:
1722 return builtin_type (objfile)->nodebug_unknown_symbol;