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c906108c | 1 | /* GDB routines for manipulating the minimal symbol tables. |
0b302171 | 2 | Copyright (C) 1992-2004, 2007-2012 Free Software Foundation, Inc. |
c906108c SS |
3 | Contributed by Cygnus Support, using pieces from other GDB modules. |
4 | ||
c5aa993b | 5 | This file is part of GDB. |
c906108c | 6 | |
c5aa993b JM |
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 | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
c5aa993b | 10 | (at your option) any later version. |
c906108c | 11 | |
c5aa993b JM |
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. | |
c906108c | 16 | |
c5aa993b | 17 | You should have received a copy of the GNU General Public License |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
c906108c SS |
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. | |
c5aa993b | 32 | |
c906108c SS |
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 | |
025bb325 | 36 | to figure out what full symbol table entries need to be read in. */ |
c906108c SS |
37 | |
38 | ||
39 | #include "defs.h" | |
9227b5eb | 40 | #include <ctype.h> |
c906108c SS |
41 | #include "gdb_string.h" |
42 | #include "symtab.h" | |
43 | #include "bfd.h" | |
0ba1096a | 44 | #include "filenames.h" |
c906108c SS |
45 | #include "symfile.h" |
46 | #include "objfiles.h" | |
47 | #include "demangle.h" | |
7ed49443 JB |
48 | #include "value.h" |
49 | #include "cp-abi.h" | |
42848c96 | 50 | #include "target.h" |
71c25dea TT |
51 | #include "cp-support.h" |
52 | #include "language.h" | |
c906108c SS |
53 | |
54 | /* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE. | |
55 | At the end, copy them all into one newly allocated location on an objfile's | |
56 | symbol obstack. */ | |
57 | ||
58 | #define BUNCH_SIZE 127 | |
59 | ||
60 | struct msym_bunch | |
c5aa993b JM |
61 | { |
62 | struct msym_bunch *next; | |
63 | struct minimal_symbol contents[BUNCH_SIZE]; | |
64 | }; | |
c906108c SS |
65 | |
66 | /* Bunch currently being filled up. | |
67 | The next field points to chain of filled bunches. */ | |
68 | ||
69 | static struct msym_bunch *msym_bunch; | |
70 | ||
71 | /* Number of slots filled in current bunch. */ | |
72 | ||
73 | static int msym_bunch_index; | |
74 | ||
75 | /* Total number of minimal symbols recorded so far for the objfile. */ | |
76 | ||
77 | static int msym_count; | |
78 | ||
b19686e0 | 79 | /* See minsyms.h. */ |
9227b5eb JB |
80 | |
81 | unsigned int | |
82 | msymbol_hash_iw (const char *string) | |
83 | { | |
84 | unsigned int hash = 0; | |
b8d56208 | 85 | |
9227b5eb JB |
86 | while (*string && *string != '(') |
87 | { | |
88 | while (isspace (*string)) | |
89 | ++string; | |
90 | if (*string && *string != '(') | |
375f3d86 | 91 | { |
59d7bcaf | 92 | hash = SYMBOL_HASH_NEXT (hash, *string); |
375f3d86 DJ |
93 | ++string; |
94 | } | |
9227b5eb | 95 | } |
261397f8 | 96 | return hash; |
9227b5eb JB |
97 | } |
98 | ||
b19686e0 | 99 | /* See minsyms.h. */ |
9227b5eb JB |
100 | |
101 | unsigned int | |
102 | msymbol_hash (const char *string) | |
103 | { | |
104 | unsigned int hash = 0; | |
b8d56208 | 105 | |
9227b5eb | 106 | for (; *string; ++string) |
59d7bcaf | 107 | hash = SYMBOL_HASH_NEXT (hash, *string); |
261397f8 | 108 | return hash; |
9227b5eb JB |
109 | } |
110 | ||
111 | /* Add the minimal symbol SYM to an objfile's minsym hash table, TABLE. */ | |
984ac464 | 112 | static void |
9227b5eb JB |
113 | add_minsym_to_hash_table (struct minimal_symbol *sym, |
114 | struct minimal_symbol **table) | |
115 | { | |
116 | if (sym->hash_next == NULL) | |
117 | { | |
f56f77c1 DC |
118 | unsigned int hash |
119 | = msymbol_hash (SYMBOL_LINKAGE_NAME (sym)) % MINIMAL_SYMBOL_HASH_SIZE; | |
b8d56208 | 120 | |
9227b5eb JB |
121 | sym->hash_next = table[hash]; |
122 | table[hash] = sym; | |
123 | } | |
124 | } | |
125 | ||
0729fd50 DB |
126 | /* Add the minimal symbol SYM to an objfile's minsym demangled hash table, |
127 | TABLE. */ | |
128 | static void | |
129 | add_minsym_to_demangled_hash_table (struct minimal_symbol *sym, | |
130 | struct minimal_symbol **table) | |
131 | { | |
132 | if (sym->demangled_hash_next == NULL) | |
133 | { | |
3e43a32a MS |
134 | unsigned int hash = msymbol_hash_iw (SYMBOL_SEARCH_NAME (sym)) |
135 | % MINIMAL_SYMBOL_HASH_SIZE; | |
b8d56208 | 136 | |
0729fd50 DB |
137 | sym->demangled_hash_next = table[hash]; |
138 | table[hash] = sym; | |
139 | } | |
140 | } | |
141 | ||
b19686e0 | 142 | /* See minsyms.h. */ |
c906108c | 143 | |
bccdca4a UW |
144 | struct objfile * |
145 | msymbol_objfile (struct minimal_symbol *sym) | |
146 | { | |
147 | struct objfile *objf; | |
148 | struct minimal_symbol *tsym; | |
149 | ||
150 | unsigned int hash | |
151 | = msymbol_hash (SYMBOL_LINKAGE_NAME (sym)) % MINIMAL_SYMBOL_HASH_SIZE; | |
152 | ||
153 | for (objf = object_files; objf; objf = objf->next) | |
154 | for (tsym = objf->msymbol_hash[hash]; tsym; tsym = tsym->hash_next) | |
155 | if (tsym == sym) | |
156 | return objf; | |
157 | ||
158 | /* We should always be able to find the objfile ... */ | |
159 | internal_error (__FILE__, __LINE__, _("failed internal consistency check")); | |
160 | } | |
161 | ||
162 | ||
c906108c SS |
163 | /* Look through all the current minimal symbol tables and find the |
164 | first minimal symbol that matches NAME. If OBJF is non-NULL, limit | |
72a5efb3 DJ |
165 | the search to that objfile. If SFILE is non-NULL, the only file-scope |
166 | symbols considered will be from that source file (global symbols are | |
167 | still preferred). Returns a pointer to the minimal symbol that | |
c906108c SS |
168 | matches, or NULL if no match is found. |
169 | ||
170 | Note: One instance where there may be duplicate minimal symbols with | |
171 | the same name is when the symbol tables for a shared library and the | |
172 | symbol tables for an executable contain global symbols with the same | |
d73f140a JB |
173 | names (the dynamic linker deals with the duplication). |
174 | ||
175 | It's also possible to have minimal symbols with different mangled | |
176 | names, but identical demangled names. For example, the GNU C++ v3 | |
177 | ABI requires the generation of two (or perhaps three) copies of | |
178 | constructor functions --- "in-charge", "not-in-charge", and | |
179 | "allocate" copies; destructors may be duplicated as well. | |
180 | Obviously, there must be distinct mangled names for each of these, | |
181 | but the demangled names are all the same: S::S or S::~S. */ | |
c906108c SS |
182 | |
183 | struct minimal_symbol * | |
aa1ee363 | 184 | lookup_minimal_symbol (const char *name, const char *sfile, |
fba45db2 | 185 | struct objfile *objf) |
c906108c SS |
186 | { |
187 | struct objfile *objfile; | |
188 | struct minimal_symbol *msymbol; | |
189 | struct minimal_symbol *found_symbol = NULL; | |
190 | struct minimal_symbol *found_file_symbol = NULL; | |
191 | struct minimal_symbol *trampoline_symbol = NULL; | |
192 | ||
261397f8 DJ |
193 | unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE; |
194 | unsigned int dem_hash = msymbol_hash_iw (name) % MINIMAL_SYMBOL_HASH_SIZE; | |
9227b5eb | 195 | |
71c25dea TT |
196 | int needtofreename = 0; |
197 | const char *modified_name; | |
198 | ||
c906108c | 199 | if (sfile != NULL) |
9f37bbcc | 200 | sfile = lbasename (sfile); |
c906108c | 201 | |
025bb325 | 202 | /* For C++, canonicalize the input name. */ |
71c25dea TT |
203 | modified_name = name; |
204 | if (current_language->la_language == language_cplus) | |
205 | { | |
206 | char *cname = cp_canonicalize_string (name); | |
b8d56208 | 207 | |
71c25dea TT |
208 | if (cname) |
209 | { | |
210 | modified_name = cname; | |
211 | needtofreename = 1; | |
212 | } | |
213 | } | |
214 | ||
c906108c SS |
215 | for (objfile = object_files; |
216 | objfile != NULL && found_symbol == NULL; | |
c5aa993b | 217 | objfile = objfile->next) |
c906108c | 218 | { |
56e3f43c | 219 | if (objf == NULL || objf == objfile |
15d123c9 | 220 | || objf == objfile->separate_debug_objfile_backlink) |
c906108c | 221 | { |
9227b5eb JB |
222 | /* Do two passes: the first over the ordinary hash table, |
223 | and the second over the demangled hash table. */ | |
0729fd50 | 224 | int pass; |
9227b5eb | 225 | |
0729fd50 | 226 | for (pass = 1; pass <= 2 && found_symbol == NULL; pass++) |
c906108c | 227 | { |
0729fd50 DB |
228 | /* Select hash list according to pass. */ |
229 | if (pass == 1) | |
230 | msymbol = objfile->msymbol_hash[hash]; | |
231 | else | |
232 | msymbol = objfile->msymbol_demangled_hash[dem_hash]; | |
233 | ||
234 | while (msymbol != NULL && found_symbol == NULL) | |
c906108c | 235 | { |
3567439c DJ |
236 | int match; |
237 | ||
238 | if (pass == 1) | |
71c25dea | 239 | { |
559a7a62 JK |
240 | int (*cmp) (const char *, const char *); |
241 | ||
242 | cmp = (case_sensitivity == case_sensitive_on | |
243 | ? strcmp : strcasecmp); | |
244 | match = cmp (SYMBOL_LINKAGE_NAME (msymbol), | |
245 | modified_name) == 0; | |
71c25dea | 246 | } |
3567439c | 247 | else |
71c25dea | 248 | { |
559a7a62 | 249 | /* The function respects CASE_SENSITIVITY. */ |
71c25dea TT |
250 | match = SYMBOL_MATCHES_SEARCH_NAME (msymbol, |
251 | modified_name); | |
252 | } | |
253 | ||
3567439c | 254 | if (match) |
c906108c | 255 | { |
0729fd50 DB |
256 | switch (MSYMBOL_TYPE (msymbol)) |
257 | { | |
258 | case mst_file_text: | |
259 | case mst_file_data: | |
260 | case mst_file_bss: | |
6314a349 | 261 | if (sfile == NULL |
0ba1096a | 262 | || filename_cmp (msymbol->filename, sfile) == 0) |
0729fd50 | 263 | found_file_symbol = msymbol; |
0729fd50 DB |
264 | break; |
265 | ||
266 | case mst_solib_trampoline: | |
267 | ||
268 | /* If a trampoline symbol is found, we prefer to | |
025bb325 | 269 | keep looking for the *real* symbol. If the |
0729fd50 | 270 | actual symbol is not found, then we'll use the |
025bb325 | 271 | trampoline entry. */ |
0729fd50 DB |
272 | if (trampoline_symbol == NULL) |
273 | trampoline_symbol = msymbol; | |
274 | break; | |
275 | ||
276 | case mst_unknown: | |
277 | default: | |
278 | found_symbol = msymbol; | |
279 | break; | |
280 | } | |
c906108c | 281 | } |
9227b5eb | 282 | |
0729fd50 DB |
283 | /* Find the next symbol on the hash chain. */ |
284 | if (pass == 1) | |
285 | msymbol = msymbol->hash_next; | |
286 | else | |
287 | msymbol = msymbol->demangled_hash_next; | |
9227b5eb | 288 | } |
c906108c SS |
289 | } |
290 | } | |
291 | } | |
71c25dea TT |
292 | |
293 | if (needtofreename) | |
294 | xfree ((void *) modified_name); | |
295 | ||
c906108c SS |
296 | /* External symbols are best. */ |
297 | if (found_symbol) | |
298 | return found_symbol; | |
299 | ||
300 | /* File-local symbols are next best. */ | |
301 | if (found_file_symbol) | |
302 | return found_file_symbol; | |
303 | ||
304 | /* Symbols for shared library trampolines are next best. */ | |
305 | if (trampoline_symbol) | |
306 | return trampoline_symbol; | |
307 | ||
308 | return NULL; | |
309 | } | |
310 | ||
b19686e0 | 311 | /* See minsyms.h. */ |
f8eba3c6 TT |
312 | |
313 | void | |
314 | iterate_over_minimal_symbols (struct objfile *objf, const char *name, | |
315 | void (*callback) (struct minimal_symbol *, | |
316 | void *), | |
317 | void *user_data) | |
318 | { | |
319 | unsigned int hash; | |
320 | struct minimal_symbol *iter; | |
321 | int (*cmp) (const char *, const char *); | |
322 | ||
323 | /* The first pass is over the ordinary hash table. */ | |
324 | hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE; | |
325 | iter = objf->msymbol_hash[hash]; | |
326 | cmp = (case_sensitivity == case_sensitive_on ? strcmp : strcasecmp); | |
327 | while (iter) | |
328 | { | |
329 | if (cmp (SYMBOL_LINKAGE_NAME (iter), name) == 0) | |
330 | (*callback) (iter, user_data); | |
331 | iter = iter->hash_next; | |
332 | } | |
333 | ||
334 | /* The second pass is over the demangled table. */ | |
335 | hash = msymbol_hash_iw (name) % MINIMAL_SYMBOL_HASH_SIZE; | |
336 | iter = objf->msymbol_demangled_hash[hash]; | |
337 | while (iter) | |
338 | { | |
339 | if (SYMBOL_MATCHES_SEARCH_NAME (iter, name)) | |
340 | (*callback) (iter, user_data); | |
341 | iter = iter->demangled_hash_next; | |
342 | } | |
343 | } | |
344 | ||
b19686e0 | 345 | /* See minsyms.h. */ |
c5aa993b | 346 | |
c906108c | 347 | struct minimal_symbol * |
5520a790 | 348 | lookup_minimal_symbol_text (const char *name, struct objfile *objf) |
c906108c SS |
349 | { |
350 | struct objfile *objfile; | |
351 | struct minimal_symbol *msymbol; | |
352 | struct minimal_symbol *found_symbol = NULL; | |
353 | struct minimal_symbol *found_file_symbol = NULL; | |
354 | ||
72a5efb3 DJ |
355 | unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE; |
356 | ||
c906108c SS |
357 | for (objfile = object_files; |
358 | objfile != NULL && found_symbol == NULL; | |
c5aa993b | 359 | objfile = objfile->next) |
c906108c | 360 | { |
56e3f43c | 361 | if (objf == NULL || objf == objfile |
15d123c9 | 362 | || objf == objfile->separate_debug_objfile_backlink) |
c906108c | 363 | { |
72a5efb3 DJ |
364 | for (msymbol = objfile->msymbol_hash[hash]; |
365 | msymbol != NULL && found_symbol == NULL; | |
366 | msymbol = msymbol->hash_next) | |
c906108c | 367 | { |
f56f77c1 | 368 | if (strcmp (SYMBOL_LINKAGE_NAME (msymbol), name) == 0 && |
0875794a JK |
369 | (MSYMBOL_TYPE (msymbol) == mst_text |
370 | || MSYMBOL_TYPE (msymbol) == mst_text_gnu_ifunc | |
371 | || MSYMBOL_TYPE (msymbol) == mst_file_text)) | |
c906108c SS |
372 | { |
373 | switch (MSYMBOL_TYPE (msymbol)) | |
374 | { | |
375 | case mst_file_text: | |
c906108c | 376 | found_file_symbol = msymbol; |
c906108c SS |
377 | break; |
378 | default: | |
379 | found_symbol = msymbol; | |
380 | break; | |
381 | } | |
382 | } | |
383 | } | |
384 | } | |
385 | } | |
386 | /* External symbols are best. */ | |
387 | if (found_symbol) | |
388 | return found_symbol; | |
389 | ||
390 | /* File-local symbols are next best. */ | |
391 | if (found_file_symbol) | |
392 | return found_file_symbol; | |
393 | ||
394 | return NULL; | |
395 | } | |
396 | ||
b19686e0 | 397 | /* See minsyms.h. */ |
907fc202 UW |
398 | |
399 | struct minimal_symbol * | |
400 | lookup_minimal_symbol_by_pc_name (CORE_ADDR pc, const char *name, | |
401 | struct objfile *objf) | |
402 | { | |
403 | struct objfile *objfile; | |
404 | struct minimal_symbol *msymbol; | |
405 | ||
406 | unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE; | |
407 | ||
408 | for (objfile = object_files; | |
409 | objfile != NULL; | |
410 | objfile = objfile->next) | |
411 | { | |
412 | if (objf == NULL || objf == objfile | |
15d123c9 | 413 | || objf == objfile->separate_debug_objfile_backlink) |
907fc202 UW |
414 | { |
415 | for (msymbol = objfile->msymbol_hash[hash]; | |
416 | msymbol != NULL; | |
417 | msymbol = msymbol->hash_next) | |
418 | { | |
419 | if (SYMBOL_VALUE_ADDRESS (msymbol) == pc | |
420 | && strcmp (SYMBOL_LINKAGE_NAME (msymbol), name) == 0) | |
421 | return msymbol; | |
422 | } | |
423 | } | |
424 | } | |
425 | ||
426 | return NULL; | |
427 | } | |
428 | ||
b19686e0 | 429 | /* See minsyms.h. */ |
c5aa993b | 430 | |
c906108c | 431 | struct minimal_symbol * |
aa1ee363 | 432 | lookup_minimal_symbol_solib_trampoline (const char *name, |
aa1ee363 | 433 | struct objfile *objf) |
c906108c SS |
434 | { |
435 | struct objfile *objfile; | |
436 | struct minimal_symbol *msymbol; | |
437 | struct minimal_symbol *found_symbol = NULL; | |
438 | ||
72a5efb3 DJ |
439 | unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE; |
440 | ||
c906108c SS |
441 | for (objfile = object_files; |
442 | objfile != NULL && found_symbol == NULL; | |
c5aa993b | 443 | objfile = objfile->next) |
c906108c | 444 | { |
56e3f43c | 445 | if (objf == NULL || objf == objfile |
15d123c9 | 446 | || objf == objfile->separate_debug_objfile_backlink) |
c906108c | 447 | { |
72a5efb3 DJ |
448 | for (msymbol = objfile->msymbol_hash[hash]; |
449 | msymbol != NULL && found_symbol == NULL; | |
450 | msymbol = msymbol->hash_next) | |
c906108c | 451 | { |
f56f77c1 | 452 | if (strcmp (SYMBOL_LINKAGE_NAME (msymbol), name) == 0 && |
c906108c SS |
453 | MSYMBOL_TYPE (msymbol) == mst_solib_trampoline) |
454 | return msymbol; | |
455 | } | |
456 | } | |
457 | } | |
458 | ||
459 | return NULL; | |
460 | } | |
461 | ||
c906108c SS |
462 | /* Search through the minimal symbol table for each objfile and find |
463 | the symbol whose address is the largest address that is still less | |
00878c6e PP |
464 | than or equal to PC, and matches SECTION (which is not NULL). |
465 | Returns a pointer to the minimal symbol if such a symbol is found, | |
466 | or NULL if PC is not in a suitable range. | |
467 | Note that we need to look through ALL the minimal symbol tables | |
468 | before deciding on the symbol that comes closest to the specified PC. | |
469 | This is because objfiles can overlap, for example objfile A has .text | |
470 | at 0x100 and .data at 0x40000 and objfile B has .text at 0x234 and | |
471 | .data at 0x40048. | |
c906108c | 472 | |
2eaf8d2a DJ |
473 | If WANT_TRAMPOLINE is set, prefer mst_solib_trampoline symbols when |
474 | there are text and trampoline symbols at the same address. | |
475 | Otherwise prefer mst_text symbols. */ | |
476 | ||
477 | static struct minimal_symbol * | |
714835d5 UW |
478 | lookup_minimal_symbol_by_pc_section_1 (CORE_ADDR pc, |
479 | struct obj_section *section, | |
2eaf8d2a | 480 | int want_trampoline) |
c906108c SS |
481 | { |
482 | int lo; | |
483 | int hi; | |
484 | int new; | |
485 | struct objfile *objfile; | |
486 | struct minimal_symbol *msymbol; | |
487 | struct minimal_symbol *best_symbol = NULL; | |
2eaf8d2a | 488 | enum minimal_symbol_type want_type, other_type; |
c906108c | 489 | |
2eaf8d2a DJ |
490 | want_type = want_trampoline ? mst_solib_trampoline : mst_text; |
491 | other_type = want_trampoline ? mst_text : mst_solib_trampoline; | |
00878c6e PP |
492 | |
493 | /* We can not require the symbol found to be in section, because | |
96225718 DJ |
494 | e.g. IRIX 6.5 mdebug relies on this code returning an absolute |
495 | symbol - but find_pc_section won't return an absolute section and | |
496 | hence the code below would skip over absolute symbols. We can | |
497 | still take advantage of the call to find_pc_section, though - the | |
498 | object file still must match. In case we have separate debug | |
499 | files, search both the file and its separate debug file. There's | |
500 | no telling which one will have the minimal symbols. */ | |
501 | ||
00878c6e | 502 | gdb_assert (section != NULL); |
96225718 | 503 | |
15d123c9 TG |
504 | for (objfile = section->objfile; |
505 | objfile != NULL; | |
506 | objfile = objfile_separate_debug_iterate (section->objfile, objfile)) | |
c906108c SS |
507 | { |
508 | /* If this objfile has a minimal symbol table, go search it using | |
c5aa993b JM |
509 | a binary search. Note that a minimal symbol table always consists |
510 | of at least two symbols, a "real" symbol and the terminating | |
511 | "null symbol". If there are no real symbols, then there is no | |
025bb325 | 512 | minimal symbol table at all. */ |
c906108c | 513 | |
15831452 | 514 | if (objfile->minimal_symbol_count > 0) |
c906108c | 515 | { |
29e8a844 DJ |
516 | int best_zero_sized = -1; |
517 | ||
15831452 | 518 | msymbol = objfile->msymbols; |
c906108c | 519 | lo = 0; |
c5aa993b | 520 | hi = objfile->minimal_symbol_count - 1; |
c906108c SS |
521 | |
522 | /* This code assumes that the minimal symbols are sorted by | |
523 | ascending address values. If the pc value is greater than or | |
524 | equal to the first symbol's address, then some symbol in this | |
525 | minimal symbol table is a suitable candidate for being the | |
526 | "best" symbol. This includes the last real symbol, for cases | |
527 | where the pc value is larger than any address in this vector. | |
528 | ||
529 | By iterating until the address associated with the current | |
530 | hi index (the endpoint of the test interval) is less than | |
531 | or equal to the desired pc value, we accomplish two things: | |
532 | (1) the case where the pc value is larger than any minimal | |
533 | symbol address is trivially solved, (2) the address associated | |
534 | with the hi index is always the one we want when the interation | |
535 | terminates. In essence, we are iterating the test interval | |
536 | down until the pc value is pushed out of it from the high end. | |
537 | ||
025bb325 | 538 | Warning: this code is trickier than it would appear at first. */ |
c906108c | 539 | |
025bb325 | 540 | /* Should also require that pc is <= end of objfile. FIXME! */ |
c906108c SS |
541 | if (pc >= SYMBOL_VALUE_ADDRESS (&msymbol[lo])) |
542 | { | |
543 | while (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) > pc) | |
544 | { | |
025bb325 MS |
545 | /* pc is still strictly less than highest address. */ |
546 | /* Note "new" will always be >= lo. */ | |
c906108c SS |
547 | new = (lo + hi) / 2; |
548 | if ((SYMBOL_VALUE_ADDRESS (&msymbol[new]) >= pc) || | |
549 | (lo == new)) | |
550 | { | |
551 | hi = new; | |
552 | } | |
553 | else | |
554 | { | |
555 | lo = new; | |
556 | } | |
557 | } | |
558 | ||
559 | /* If we have multiple symbols at the same address, we want | |
c5aa993b JM |
560 | hi to point to the last one. That way we can find the |
561 | right symbol if it has an index greater than hi. */ | |
562 | while (hi < objfile->minimal_symbol_count - 1 | |
c906108c | 563 | && (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) |
c5aa993b | 564 | == SYMBOL_VALUE_ADDRESS (&msymbol[hi + 1]))) |
c906108c SS |
565 | hi++; |
566 | ||
29e8a844 DJ |
567 | /* Skip various undesirable symbols. */ |
568 | while (hi >= 0) | |
569 | { | |
570 | /* Skip any absolute symbols. This is apparently | |
571 | what adb and dbx do, and is needed for the CM-5. | |
572 | There are two known possible problems: (1) on | |
573 | ELF, apparently end, edata, etc. are absolute. | |
574 | Not sure ignoring them here is a big deal, but if | |
575 | we want to use them, the fix would go in | |
576 | elfread.c. (2) I think shared library entry | |
577 | points on the NeXT are absolute. If we want | |
578 | special handling for this it probably should be | |
579 | triggered by a special mst_abs_or_lib or some | |
580 | such. */ | |
581 | ||
712f90be | 582 | if (MSYMBOL_TYPE (&msymbol[hi]) == mst_abs) |
29e8a844 DJ |
583 | { |
584 | hi--; | |
585 | continue; | |
586 | } | |
587 | ||
588 | /* If SECTION was specified, skip any symbol from | |
589 | wrong section. */ | |
590 | if (section | |
591 | /* Some types of debug info, such as COFF, | |
592 | don't fill the bfd_section member, so don't | |
593 | throw away symbols on those platforms. */ | |
714835d5 UW |
594 | && SYMBOL_OBJ_SECTION (&msymbol[hi]) != NULL |
595 | && (!matching_obj_sections | |
596 | (SYMBOL_OBJ_SECTION (&msymbol[hi]), section))) | |
29e8a844 DJ |
597 | { |
598 | hi--; | |
599 | continue; | |
600 | } | |
601 | ||
2eaf8d2a DJ |
602 | /* If we are looking for a trampoline and this is a |
603 | text symbol, or the other way around, check the | |
177b42fe | 604 | preceding symbol too. If they are otherwise |
2eaf8d2a DJ |
605 | identical prefer that one. */ |
606 | if (hi > 0 | |
607 | && MSYMBOL_TYPE (&msymbol[hi]) == other_type | |
608 | && MSYMBOL_TYPE (&msymbol[hi - 1]) == want_type | |
609 | && (MSYMBOL_SIZE (&msymbol[hi]) | |
610 | == MSYMBOL_SIZE (&msymbol[hi - 1])) | |
611 | && (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) | |
612 | == SYMBOL_VALUE_ADDRESS (&msymbol[hi - 1])) | |
714835d5 UW |
613 | && (SYMBOL_OBJ_SECTION (&msymbol[hi]) |
614 | == SYMBOL_OBJ_SECTION (&msymbol[hi - 1]))) | |
2eaf8d2a DJ |
615 | { |
616 | hi--; | |
617 | continue; | |
618 | } | |
619 | ||
29e8a844 DJ |
620 | /* If the minimal symbol has a zero size, save it |
621 | but keep scanning backwards looking for one with | |
622 | a non-zero size. A zero size may mean that the | |
623 | symbol isn't an object or function (e.g. a | |
624 | label), or it may just mean that the size was not | |
625 | specified. */ | |
626 | if (MSYMBOL_SIZE (&msymbol[hi]) == 0 | |
627 | && best_zero_sized == -1) | |
628 | { | |
629 | best_zero_sized = hi; | |
630 | hi--; | |
631 | continue; | |
632 | } | |
633 | ||
f7a6bb70 DJ |
634 | /* If we are past the end of the current symbol, try |
635 | the previous symbol if it has a larger overlapping | |
636 | size. This happens on i686-pc-linux-gnu with glibc; | |
637 | the nocancel variants of system calls are inside | |
638 | the cancellable variants, but both have sizes. */ | |
639 | if (hi > 0 | |
640 | && MSYMBOL_SIZE (&msymbol[hi]) != 0 | |
641 | && pc >= (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) | |
642 | + MSYMBOL_SIZE (&msymbol[hi])) | |
643 | && pc < (SYMBOL_VALUE_ADDRESS (&msymbol[hi - 1]) | |
644 | + MSYMBOL_SIZE (&msymbol[hi - 1]))) | |
645 | { | |
646 | hi--; | |
647 | continue; | |
648 | } | |
649 | ||
29e8a844 DJ |
650 | /* Otherwise, this symbol must be as good as we're going |
651 | to get. */ | |
652 | break; | |
653 | } | |
654 | ||
655 | /* If HI has a zero size, and best_zero_sized is set, | |
656 | then we had two or more zero-sized symbols; prefer | |
657 | the first one we found (which may have a higher | |
658 | address). Also, if we ran off the end, be sure | |
659 | to back up. */ | |
660 | if (best_zero_sized != -1 | |
661 | && (hi < 0 || MSYMBOL_SIZE (&msymbol[hi]) == 0)) | |
662 | hi = best_zero_sized; | |
663 | ||
664 | /* If the minimal symbol has a non-zero size, and this | |
665 | PC appears to be outside the symbol's contents, then | |
666 | refuse to use this symbol. If we found a zero-sized | |
667 | symbol with an address greater than this symbol's, | |
668 | use that instead. We assume that if symbols have | |
669 | specified sizes, they do not overlap. */ | |
670 | ||
671 | if (hi >= 0 | |
672 | && MSYMBOL_SIZE (&msymbol[hi]) != 0 | |
673 | && pc >= (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) | |
674 | + MSYMBOL_SIZE (&msymbol[hi]))) | |
675 | { | |
676 | if (best_zero_sized != -1) | |
677 | hi = best_zero_sized; | |
678 | else | |
679 | /* Go on to the next object file. */ | |
680 | continue; | |
681 | } | |
682 | ||
c906108c | 683 | /* The minimal symbol indexed by hi now is the best one in this |
c5aa993b | 684 | objfile's minimal symbol table. See if it is the best one |
025bb325 | 685 | overall. */ |
c906108c | 686 | |
c906108c SS |
687 | if (hi >= 0 |
688 | && ((best_symbol == NULL) || | |
c5aa993b | 689 | (SYMBOL_VALUE_ADDRESS (best_symbol) < |
c906108c SS |
690 | SYMBOL_VALUE_ADDRESS (&msymbol[hi])))) |
691 | { | |
692 | best_symbol = &msymbol[hi]; | |
693 | } | |
694 | } | |
695 | } | |
696 | } | |
697 | return (best_symbol); | |
698 | } | |
699 | ||
2eaf8d2a | 700 | struct minimal_symbol * |
714835d5 | 701 | lookup_minimal_symbol_by_pc_section (CORE_ADDR pc, struct obj_section *section) |
2eaf8d2a | 702 | { |
00878c6e PP |
703 | if (section == NULL) |
704 | { | |
705 | /* NOTE: cagney/2004-01-27: This was using find_pc_mapped_section to | |
706 | force the section but that (well unless you're doing overlay | |
707 | debugging) always returns NULL making the call somewhat useless. */ | |
708 | section = find_pc_section (pc); | |
709 | if (section == NULL) | |
710 | return NULL; | |
711 | } | |
2eaf8d2a DJ |
712 | return lookup_minimal_symbol_by_pc_section_1 (pc, section, 0); |
713 | } | |
714 | ||
b19686e0 | 715 | /* See minsyms.h. */ |
c906108c SS |
716 | |
717 | struct minimal_symbol * | |
fba45db2 | 718 | lookup_minimal_symbol_by_pc (CORE_ADDR pc) |
c906108c | 719 | { |
00878c6e | 720 | return lookup_minimal_symbol_by_pc_section (pc, NULL); |
c906108c | 721 | } |
0d5392b8 | 722 | |
0875794a JK |
723 | /* Return non-zero iff PC is in an STT_GNU_IFUNC function resolver. */ |
724 | ||
725 | int | |
726 | in_gnu_ifunc_stub (CORE_ADDR pc) | |
727 | { | |
728 | struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (pc); | |
729 | ||
730 | return msymbol && MSYMBOL_TYPE (msymbol) == mst_text_gnu_ifunc; | |
731 | } | |
732 | ||
07be84bf JK |
733 | /* See elf_gnu_ifunc_resolve_addr for its real implementation. */ |
734 | ||
735 | static CORE_ADDR | |
736 | stub_gnu_ifunc_resolve_addr (struct gdbarch *gdbarch, CORE_ADDR pc) | |
737 | { | |
738 | error (_("GDB cannot resolve STT_GNU_IFUNC symbol at address %s without " | |
739 | "the ELF support compiled in."), | |
740 | paddress (gdbarch, pc)); | |
741 | } | |
742 | ||
743 | /* See elf_gnu_ifunc_resolve_name for its real implementation. */ | |
744 | ||
745 | static int | |
746 | stub_gnu_ifunc_resolve_name (const char *function_name, | |
747 | CORE_ADDR *function_address_p) | |
748 | { | |
749 | error (_("GDB cannot resolve STT_GNU_IFUNC symbol \"%s\" without " | |
750 | "the ELF support compiled in."), | |
751 | function_name); | |
752 | } | |
753 | ||
0e30163f JK |
754 | /* See elf_gnu_ifunc_resolver_stop for its real implementation. */ |
755 | ||
756 | static void | |
757 | stub_gnu_ifunc_resolver_stop (struct breakpoint *b) | |
758 | { | |
759 | internal_error (__FILE__, __LINE__, | |
760 | _("elf_gnu_ifunc_resolver_stop cannot be reached.")); | |
761 | } | |
762 | ||
763 | /* See elf_gnu_ifunc_resolver_return_stop for its real implementation. */ | |
764 | ||
765 | static void | |
766 | stub_gnu_ifunc_resolver_return_stop (struct breakpoint *b) | |
767 | { | |
768 | internal_error (__FILE__, __LINE__, | |
769 | _("elf_gnu_ifunc_resolver_return_stop cannot be reached.")); | |
770 | } | |
771 | ||
07be84bf JK |
772 | /* See elf_gnu_ifunc_fns for its real implementation. */ |
773 | ||
774 | static const struct gnu_ifunc_fns stub_gnu_ifunc_fns = | |
775 | { | |
776 | stub_gnu_ifunc_resolve_addr, | |
777 | stub_gnu_ifunc_resolve_name, | |
0e30163f JK |
778 | stub_gnu_ifunc_resolver_stop, |
779 | stub_gnu_ifunc_resolver_return_stop, | |
07be84bf JK |
780 | }; |
781 | ||
782 | /* A placeholder for &elf_gnu_ifunc_fns. */ | |
783 | ||
784 | const struct gnu_ifunc_fns *gnu_ifunc_fns_p = &stub_gnu_ifunc_fns; | |
785 | ||
b19686e0 | 786 | /* See minsyms.h. */ |
0d5392b8 TT |
787 | |
788 | struct minimal_symbol * | |
789 | lookup_minimal_symbol_and_objfile (const char *name, | |
790 | struct objfile **objfile_p) | |
791 | { | |
792 | struct objfile *objfile; | |
793 | unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE; | |
794 | ||
795 | ALL_OBJFILES (objfile) | |
796 | { | |
797 | struct minimal_symbol *msym; | |
798 | ||
799 | for (msym = objfile->msymbol_hash[hash]; | |
800 | msym != NULL; | |
801 | msym = msym->hash_next) | |
802 | { | |
803 | if (strcmp (SYMBOL_LINKAGE_NAME (msym), name) == 0) | |
804 | { | |
805 | *objfile_p = objfile; | |
806 | return msym; | |
807 | } | |
808 | } | |
809 | } | |
810 | ||
811 | return 0; | |
812 | } | |
c906108c | 813 | \f |
c5aa993b | 814 | |
025bb325 | 815 | /* Return leading symbol character for a BFD. If BFD is NULL, |
c906108c SS |
816 | return the leading symbol character from the main objfile. */ |
817 | ||
a14ed312 | 818 | static int get_symbol_leading_char (bfd *); |
c906108c SS |
819 | |
820 | static int | |
fba45db2 | 821 | get_symbol_leading_char (bfd *abfd) |
c906108c SS |
822 | { |
823 | if (abfd != NULL) | |
824 | return bfd_get_symbol_leading_char (abfd); | |
825 | if (symfile_objfile != NULL && symfile_objfile->obfd != NULL) | |
826 | return bfd_get_symbol_leading_char (symfile_objfile->obfd); | |
827 | return 0; | |
828 | } | |
829 | ||
b19686e0 | 830 | /* See minsyms.h. */ |
c906108c SS |
831 | |
832 | void | |
fba45db2 | 833 | init_minimal_symbol_collection (void) |
c906108c SS |
834 | { |
835 | msym_count = 0; | |
836 | msym_bunch = NULL; | |
b19686e0 TT |
837 | /* Note that presetting msym_bunch_index to BUNCH_SIZE causes the |
838 | first call to save a minimal symbol to allocate the memory for | |
839 | the first bunch. */ | |
c906108c SS |
840 | msym_bunch_index = BUNCH_SIZE; |
841 | } | |
842 | ||
b19686e0 TT |
843 | /* See minsyms.h. */ |
844 | ||
c906108c | 845 | void |
fba45db2 KB |
846 | prim_record_minimal_symbol (const char *name, CORE_ADDR address, |
847 | enum minimal_symbol_type ms_type, | |
848 | struct objfile *objfile) | |
c906108c SS |
849 | { |
850 | int section; | |
851 | ||
852 | switch (ms_type) | |
853 | { | |
854 | case mst_text: | |
0875794a | 855 | case mst_text_gnu_ifunc: |
c906108c SS |
856 | case mst_file_text: |
857 | case mst_solib_trampoline: | |
b8fbeb18 | 858 | section = SECT_OFF_TEXT (objfile); |
c906108c SS |
859 | break; |
860 | case mst_data: | |
861 | case mst_file_data: | |
b8fbeb18 | 862 | section = SECT_OFF_DATA (objfile); |
c906108c SS |
863 | break; |
864 | case mst_bss: | |
865 | case mst_file_bss: | |
b8fbeb18 | 866 | section = SECT_OFF_BSS (objfile); |
c906108c SS |
867 | break; |
868 | default: | |
869 | section = -1; | |
870 | } | |
871 | ||
872 | prim_record_minimal_symbol_and_info (name, address, ms_type, | |
b887350f | 873 | section, NULL, objfile); |
c906108c SS |
874 | } |
875 | ||
b19686e0 | 876 | /* See minsyms.h. */ |
c906108c SS |
877 | |
878 | struct minimal_symbol * | |
04a679b8 TT |
879 | prim_record_minimal_symbol_full (const char *name, int name_len, int copy_name, |
880 | CORE_ADDR address, | |
881 | enum minimal_symbol_type ms_type, | |
882 | int section, | |
883 | asection *bfd_section, | |
884 | struct objfile *objfile) | |
c906108c | 885 | { |
714835d5 | 886 | struct obj_section *obj_section; |
52f0bd74 AC |
887 | struct msym_bunch *new; |
888 | struct minimal_symbol *msymbol; | |
c906108c | 889 | |
66337bb1 CV |
890 | /* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into |
891 | the minimal symbols, because if there is also another symbol | |
892 | at the same address (e.g. the first function of the file), | |
893 | lookup_minimal_symbol_by_pc would have no way of getting the | |
894 | right one. */ | |
895 | if (ms_type == mst_file_text && name[0] == 'g' | |
896 | && (strcmp (name, GCC_COMPILED_FLAG_SYMBOL) == 0 | |
897 | || strcmp (name, GCC2_COMPILED_FLAG_SYMBOL) == 0)) | |
898 | return (NULL); | |
899 | ||
900 | /* It's safe to strip the leading char here once, since the name | |
025bb325 | 901 | is also stored stripped in the minimal symbol table. */ |
66337bb1 | 902 | if (name[0] == get_symbol_leading_char (objfile->obfd)) |
04a679b8 TT |
903 | { |
904 | ++name; | |
905 | --name_len; | |
906 | } | |
66337bb1 CV |
907 | |
908 | if (ms_type == mst_file_text && strncmp (name, "__gnu_compiled", 14) == 0) | |
909 | return (NULL); | |
c906108c SS |
910 | |
911 | if (msym_bunch_index == BUNCH_SIZE) | |
912 | { | |
edb3359d | 913 | new = XCALLOC (1, struct msym_bunch); |
c906108c | 914 | msym_bunch_index = 0; |
c5aa993b | 915 | new->next = msym_bunch; |
c906108c SS |
916 | msym_bunch = new; |
917 | } | |
c5aa993b | 918 | msymbol = &msym_bunch->contents[msym_bunch_index]; |
33e5013e | 919 | SYMBOL_SET_LANGUAGE (msymbol, language_auto); |
04a679b8 | 920 | SYMBOL_SET_NAMES (msymbol, name, name_len, copy_name, objfile); |
2de7ced7 | 921 | |
c906108c SS |
922 | SYMBOL_VALUE_ADDRESS (msymbol) = address; |
923 | SYMBOL_SECTION (msymbol) = section; | |
714835d5 UW |
924 | SYMBOL_OBJ_SECTION (msymbol) = NULL; |
925 | ||
926 | /* Find obj_section corresponding to bfd_section. */ | |
927 | if (bfd_section) | |
928 | ALL_OBJFILE_OSECTIONS (objfile, obj_section) | |
929 | { | |
930 | if (obj_section->the_bfd_section == bfd_section) | |
931 | { | |
932 | SYMBOL_OBJ_SECTION (msymbol) = obj_section; | |
933 | break; | |
934 | } | |
935 | } | |
c906108c SS |
936 | |
937 | MSYMBOL_TYPE (msymbol) = ms_type; | |
b887350f TT |
938 | MSYMBOL_TARGET_FLAG_1 (msymbol) = 0; |
939 | MSYMBOL_TARGET_FLAG_2 (msymbol) = 0; | |
f594e5e9 | 940 | MSYMBOL_SIZE (msymbol) = 0; |
9227b5eb | 941 | |
a79dea61 | 942 | /* The hash pointers must be cleared! If they're not, |
025bb325 | 943 | add_minsym_to_hash_table will NOT add this msymbol to the hash table. */ |
9227b5eb JB |
944 | msymbol->hash_next = NULL; |
945 | msymbol->demangled_hash_next = NULL; | |
946 | ||
c906108c SS |
947 | msym_bunch_index++; |
948 | msym_count++; | |
949 | OBJSTAT (objfile, n_minsyms++); | |
950 | return msymbol; | |
951 | } | |
952 | ||
b19686e0 | 953 | /* See minsyms.h. */ |
04a679b8 TT |
954 | |
955 | struct minimal_symbol * | |
956 | prim_record_minimal_symbol_and_info (const char *name, CORE_ADDR address, | |
957 | enum minimal_symbol_type ms_type, | |
958 | int section, | |
959 | asection *bfd_section, | |
960 | struct objfile *objfile) | |
961 | { | |
962 | return prim_record_minimal_symbol_full (name, strlen (name), 1, | |
963 | address, ms_type, section, | |
964 | bfd_section, objfile); | |
965 | } | |
966 | ||
c906108c | 967 | /* Compare two minimal symbols by address and return a signed result based |
025bb325 | 968 | on unsigned comparisons, so that we sort into unsigned numeric order. |
c906108c SS |
969 | Within groups with the same address, sort by name. */ |
970 | ||
971 | static int | |
12b9c64f | 972 | compare_minimal_symbols (const void *fn1p, const void *fn2p) |
c906108c | 973 | { |
52f0bd74 AC |
974 | const struct minimal_symbol *fn1; |
975 | const struct minimal_symbol *fn2; | |
c906108c SS |
976 | |
977 | fn1 = (const struct minimal_symbol *) fn1p; | |
978 | fn2 = (const struct minimal_symbol *) fn2p; | |
979 | ||
980 | if (SYMBOL_VALUE_ADDRESS (fn1) < SYMBOL_VALUE_ADDRESS (fn2)) | |
981 | { | |
025bb325 | 982 | return (-1); /* addr 1 is less than addr 2. */ |
c906108c SS |
983 | } |
984 | else if (SYMBOL_VALUE_ADDRESS (fn1) > SYMBOL_VALUE_ADDRESS (fn2)) | |
985 | { | |
025bb325 | 986 | return (1); /* addr 1 is greater than addr 2. */ |
c906108c | 987 | } |
c5aa993b JM |
988 | else |
989 | /* addrs are equal: sort by name */ | |
c906108c | 990 | { |
0d5cff50 DE |
991 | const char *name1 = SYMBOL_LINKAGE_NAME (fn1); |
992 | const char *name2 = SYMBOL_LINKAGE_NAME (fn2); | |
c906108c SS |
993 | |
994 | if (name1 && name2) /* both have names */ | |
995 | return strcmp (name1, name2); | |
996 | else if (name2) | |
025bb325 MS |
997 | return 1; /* fn1 has no name, so it is "less". */ |
998 | else if (name1) /* fn2 has no name, so it is "less". */ | |
c906108c SS |
999 | return -1; |
1000 | else | |
025bb325 | 1001 | return (0); /* Neither has a name, so they're equal. */ |
c906108c SS |
1002 | } |
1003 | } | |
1004 | ||
1005 | /* Discard the currently collected minimal symbols, if any. If we wish | |
1006 | to save them for later use, we must have already copied them somewhere | |
1007 | else before calling this function. | |
1008 | ||
1009 | FIXME: We could allocate the minimal symbol bunches on their own | |
1010 | obstack and then simply blow the obstack away when we are done with | |
025bb325 | 1011 | it. Is it worth the extra trouble though? */ |
c906108c | 1012 | |
56e290f4 AC |
1013 | static void |
1014 | do_discard_minimal_symbols_cleanup (void *arg) | |
c906108c | 1015 | { |
52f0bd74 | 1016 | struct msym_bunch *next; |
c906108c SS |
1017 | |
1018 | while (msym_bunch != NULL) | |
1019 | { | |
c5aa993b | 1020 | next = msym_bunch->next; |
b8c9b27d | 1021 | xfree (msym_bunch); |
c906108c SS |
1022 | msym_bunch = next; |
1023 | } | |
1024 | } | |
1025 | ||
b19686e0 TT |
1026 | /* See minsyms.h. */ |
1027 | ||
56e290f4 AC |
1028 | struct cleanup * |
1029 | make_cleanup_discard_minimal_symbols (void) | |
1030 | { | |
1031 | return make_cleanup (do_discard_minimal_symbols_cleanup, 0); | |
1032 | } | |
1033 | ||
1034 | ||
9227b5eb | 1035 | |
c906108c SS |
1036 | /* Compact duplicate entries out of a minimal symbol table by walking |
1037 | through the table and compacting out entries with duplicate addresses | |
1038 | and matching names. Return the number of entries remaining. | |
1039 | ||
1040 | On entry, the table resides between msymbol[0] and msymbol[mcount]. | |
1041 | On exit, it resides between msymbol[0] and msymbol[result_count]. | |
1042 | ||
1043 | When files contain multiple sources of symbol information, it is | |
1044 | possible for the minimal symbol table to contain many duplicate entries. | |
1045 | As an example, SVR4 systems use ELF formatted object files, which | |
1046 | usually contain at least two different types of symbol tables (a | |
1047 | standard ELF one and a smaller dynamic linking table), as well as | |
1048 | DWARF debugging information for files compiled with -g. | |
1049 | ||
1050 | Without compacting, the minimal symbol table for gdb itself contains | |
1051 | over a 1000 duplicates, about a third of the total table size. Aside | |
1052 | from the potential trap of not noticing that two successive entries | |
1053 | identify the same location, this duplication impacts the time required | |
1054 | to linearly scan the table, which is done in a number of places. So we | |
1055 | just do one linear scan here and toss out the duplicates. | |
1056 | ||
1057 | Note that we are not concerned here about recovering the space that | |
1058 | is potentially freed up, because the strings themselves are allocated | |
4a146b47 | 1059 | on the objfile_obstack, and will get automatically freed when the symbol |
c906108c SS |
1060 | table is freed. The caller can free up the unused minimal symbols at |
1061 | the end of the compacted region if their allocation strategy allows it. | |
1062 | ||
1063 | Also note we only go up to the next to last entry within the loop | |
1064 | and then copy the last entry explicitly after the loop terminates. | |
1065 | ||
1066 | Since the different sources of information for each symbol may | |
1067 | have different levels of "completeness", we may have duplicates | |
1068 | that have one entry with type "mst_unknown" and the other with a | |
1069 | known type. So if the one we are leaving alone has type mst_unknown, | |
1070 | overwrite its type with the type from the one we are compacting out. */ | |
1071 | ||
1072 | static int | |
fba45db2 KB |
1073 | compact_minimal_symbols (struct minimal_symbol *msymbol, int mcount, |
1074 | struct objfile *objfile) | |
c906108c SS |
1075 | { |
1076 | struct minimal_symbol *copyfrom; | |
1077 | struct minimal_symbol *copyto; | |
1078 | ||
1079 | if (mcount > 0) | |
1080 | { | |
1081 | copyfrom = copyto = msymbol; | |
1082 | while (copyfrom < msymbol + mcount - 1) | |
1083 | { | |
6314a349 AC |
1084 | if (SYMBOL_VALUE_ADDRESS (copyfrom) |
1085 | == SYMBOL_VALUE_ADDRESS ((copyfrom + 1)) | |
1086 | && strcmp (SYMBOL_LINKAGE_NAME (copyfrom), | |
1087 | SYMBOL_LINKAGE_NAME ((copyfrom + 1))) == 0) | |
c906108c | 1088 | { |
c5aa993b | 1089 | if (MSYMBOL_TYPE ((copyfrom + 1)) == mst_unknown) |
c906108c SS |
1090 | { |
1091 | MSYMBOL_TYPE ((copyfrom + 1)) = MSYMBOL_TYPE (copyfrom); | |
1092 | } | |
1093 | copyfrom++; | |
1094 | } | |
1095 | else | |
afbb8d7a | 1096 | *copyto++ = *copyfrom++; |
c906108c SS |
1097 | } |
1098 | *copyto++ = *copyfrom++; | |
1099 | mcount = copyto - msymbol; | |
1100 | } | |
1101 | return (mcount); | |
1102 | } | |
1103 | ||
afbb8d7a KB |
1104 | /* Build (or rebuild) the minimal symbol hash tables. This is necessary |
1105 | after compacting or sorting the table since the entries move around | |
025bb325 | 1106 | thus causing the internal minimal_symbol pointers to become jumbled. */ |
afbb8d7a KB |
1107 | |
1108 | static void | |
1109 | build_minimal_symbol_hash_tables (struct objfile *objfile) | |
1110 | { | |
1111 | int i; | |
1112 | struct minimal_symbol *msym; | |
1113 | ||
025bb325 | 1114 | /* Clear the hash tables. */ |
afbb8d7a KB |
1115 | for (i = 0; i < MINIMAL_SYMBOL_HASH_SIZE; i++) |
1116 | { | |
1117 | objfile->msymbol_hash[i] = 0; | |
1118 | objfile->msymbol_demangled_hash[i] = 0; | |
1119 | } | |
1120 | ||
025bb325 | 1121 | /* Now, (re)insert the actual entries. */ |
afbb8d7a KB |
1122 | for (i = objfile->minimal_symbol_count, msym = objfile->msymbols; |
1123 | i > 0; | |
1124 | i--, msym++) | |
1125 | { | |
1126 | msym->hash_next = 0; | |
1127 | add_minsym_to_hash_table (msym, objfile->msymbol_hash); | |
1128 | ||
1129 | msym->demangled_hash_next = 0; | |
4725b721 | 1130 | if (SYMBOL_SEARCH_NAME (msym) != SYMBOL_LINKAGE_NAME (msym)) |
afbb8d7a KB |
1131 | add_minsym_to_demangled_hash_table (msym, |
1132 | objfile->msymbol_demangled_hash); | |
1133 | } | |
1134 | } | |
1135 | ||
c906108c SS |
1136 | /* Add the minimal symbols in the existing bunches to the objfile's official |
1137 | minimal symbol table. In most cases there is no minimal symbol table yet | |
1138 | for this objfile, and the existing bunches are used to create one. Once | |
1139 | in a while (for shared libraries for example), we add symbols (e.g. common | |
1140 | symbols) to an existing objfile. | |
1141 | ||
1142 | Because of the way minimal symbols are collected, we generally have no way | |
1143 | of knowing what source language applies to any particular minimal symbol. | |
1144 | Specifically, we have no way of knowing if the minimal symbol comes from a | |
1145 | C++ compilation unit or not. So for the sake of supporting cached | |
1146 | demangled C++ names, we have no choice but to try and demangle each new one | |
1147 | that comes in. If the demangling succeeds, then we assume it is a C++ | |
1148 | symbol and set the symbol's language and demangled name fields | |
1149 | appropriately. Note that in order to avoid unnecessary demanglings, and | |
1150 | allocating obstack space that subsequently can't be freed for the demangled | |
1151 | names, we mark all newly added symbols with language_auto. After | |
1152 | compaction of the minimal symbols, we go back and scan the entire minimal | |
1153 | symbol table looking for these new symbols. For each new symbol we attempt | |
1154 | to demangle it, and if successful, record it as a language_cplus symbol | |
1155 | and cache the demangled form on the symbol obstack. Symbols which don't | |
1156 | demangle are marked as language_unknown symbols, which inhibits future | |
025bb325 | 1157 | attempts to demangle them if we later add more minimal symbols. */ |
c906108c SS |
1158 | |
1159 | void | |
fba45db2 | 1160 | install_minimal_symbols (struct objfile *objfile) |
c906108c | 1161 | { |
52f0bd74 AC |
1162 | int bindex; |
1163 | int mcount; | |
1164 | struct msym_bunch *bunch; | |
1165 | struct minimal_symbol *msymbols; | |
c906108c | 1166 | int alloc_count; |
c906108c SS |
1167 | |
1168 | if (msym_count > 0) | |
1169 | { | |
45cfd468 DE |
1170 | if (symtab_create_debug) |
1171 | { | |
1172 | fprintf_unfiltered (gdb_stdlog, | |
1173 | "Installing %d minimal symbols of objfile %s.\n", | |
1174 | msym_count, objfile->name); | |
1175 | } | |
1176 | ||
c906108c | 1177 | /* Allocate enough space in the obstack, into which we will gather the |
c5aa993b JM |
1178 | bunches of new and existing minimal symbols, sort them, and then |
1179 | compact out the duplicate entries. Once we have a final table, | |
1180 | we will give back the excess space. */ | |
c906108c SS |
1181 | |
1182 | alloc_count = msym_count + objfile->minimal_symbol_count + 1; | |
4a146b47 | 1183 | obstack_blank (&objfile->objfile_obstack, |
c906108c SS |
1184 | alloc_count * sizeof (struct minimal_symbol)); |
1185 | msymbols = (struct minimal_symbol *) | |
4a146b47 | 1186 | obstack_base (&objfile->objfile_obstack); |
c906108c SS |
1187 | |
1188 | /* Copy in the existing minimal symbols, if there are any. */ | |
1189 | ||
1190 | if (objfile->minimal_symbol_count) | |
c5aa993b JM |
1191 | memcpy ((char *) msymbols, (char *) objfile->msymbols, |
1192 | objfile->minimal_symbol_count * sizeof (struct minimal_symbol)); | |
c906108c SS |
1193 | |
1194 | /* Walk through the list of minimal symbol bunches, adding each symbol | |
c5aa993b JM |
1195 | to the new contiguous array of symbols. Note that we start with the |
1196 | current, possibly partially filled bunch (thus we use the current | |
1197 | msym_bunch_index for the first bunch we copy over), and thereafter | |
025bb325 | 1198 | each bunch is full. */ |
c5aa993b | 1199 | |
c906108c | 1200 | mcount = objfile->minimal_symbol_count; |
c5aa993b JM |
1201 | |
1202 | for (bunch = msym_bunch; bunch != NULL; bunch = bunch->next) | |
c906108c SS |
1203 | { |
1204 | for (bindex = 0; bindex < msym_bunch_index; bindex++, mcount++) | |
66337bb1 | 1205 | msymbols[mcount] = bunch->contents[bindex]; |
c906108c SS |
1206 | msym_bunch_index = BUNCH_SIZE; |
1207 | } | |
1208 | ||
1209 | /* Sort the minimal symbols by address. */ | |
c5aa993b | 1210 | |
c906108c SS |
1211 | qsort (msymbols, mcount, sizeof (struct minimal_symbol), |
1212 | compare_minimal_symbols); | |
c5aa993b | 1213 | |
c906108c | 1214 | /* Compact out any duplicates, and free up whatever space we are |
c5aa993b JM |
1215 | no longer using. */ |
1216 | ||
9227b5eb | 1217 | mcount = compact_minimal_symbols (msymbols, mcount, objfile); |
c906108c | 1218 | |
4a146b47 | 1219 | obstack_blank (&objfile->objfile_obstack, |
c5aa993b | 1220 | (mcount + 1 - alloc_count) * sizeof (struct minimal_symbol)); |
c906108c | 1221 | msymbols = (struct minimal_symbol *) |
4a146b47 | 1222 | obstack_finish (&objfile->objfile_obstack); |
c906108c SS |
1223 | |
1224 | /* We also terminate the minimal symbol table with a "null symbol", | |
c5aa993b JM |
1225 | which is *not* included in the size of the table. This makes it |
1226 | easier to find the end of the table when we are handed a pointer | |
1227 | to some symbol in the middle of it. Zero out the fields in the | |
1228 | "null symbol" allocated at the end of the array. Note that the | |
1229 | symbol count does *not* include this null symbol, which is why it | |
025bb325 | 1230 | is indexed by mcount and not mcount-1. */ |
c906108c | 1231 | |
f56f77c1 | 1232 | SYMBOL_LINKAGE_NAME (&msymbols[mcount]) = NULL; |
c906108c | 1233 | SYMBOL_VALUE_ADDRESS (&msymbols[mcount]) = 0; |
b887350f TT |
1234 | MSYMBOL_TARGET_FLAG_1 (&msymbols[mcount]) = 0; |
1235 | MSYMBOL_TARGET_FLAG_2 (&msymbols[mcount]) = 0; | |
f594e5e9 | 1236 | MSYMBOL_SIZE (&msymbols[mcount]) = 0; |
c906108c | 1237 | MSYMBOL_TYPE (&msymbols[mcount]) = mst_unknown; |
33e5013e | 1238 | SYMBOL_SET_LANGUAGE (&msymbols[mcount], language_unknown); |
c906108c SS |
1239 | |
1240 | /* Attach the minimal symbol table to the specified objfile. | |
4a146b47 | 1241 | The strings themselves are also located in the objfile_obstack |
c5aa993b | 1242 | of this objfile. */ |
c906108c | 1243 | |
c5aa993b JM |
1244 | objfile->minimal_symbol_count = mcount; |
1245 | objfile->msymbols = msymbols; | |
c906108c | 1246 | |
7ed49443 JB |
1247 | /* Try to guess the appropriate C++ ABI by looking at the names |
1248 | of the minimal symbols in the table. */ | |
1249 | { | |
1250 | int i; | |
1251 | ||
1252 | for (i = 0; i < mcount; i++) | |
1253 | { | |
6aca59a3 DJ |
1254 | /* If a symbol's name starts with _Z and was successfully |
1255 | demangled, then we can assume we've found a GNU v3 symbol. | |
1256 | For now we set the C++ ABI globally; if the user is | |
1257 | mixing ABIs then the user will need to "set cp-abi" | |
1258 | manually. */ | |
f56f77c1 | 1259 | const char *name = SYMBOL_LINKAGE_NAME (&objfile->msymbols[i]); |
b8d56208 | 1260 | |
6aca59a3 DJ |
1261 | if (name[0] == '_' && name[1] == 'Z' |
1262 | && SYMBOL_DEMANGLED_NAME (&objfile->msymbols[i]) != NULL) | |
7ed49443 | 1263 | { |
fe1f4a5e | 1264 | set_cp_abi_as_auto_default ("gnu-v3"); |
7ed49443 JB |
1265 | break; |
1266 | } | |
1267 | } | |
1268 | } | |
afbb8d7a KB |
1269 | |
1270 | /* Now build the hash tables; we can't do this incrementally | |
1271 | at an earlier point since we weren't finished with the obstack | |
1272 | yet. (And if the msymbol obstack gets moved, all the internal | |
025bb325 | 1273 | pointers to other msymbols need to be adjusted.) */ |
afbb8d7a | 1274 | build_minimal_symbol_hash_tables (objfile); |
c906108c SS |
1275 | } |
1276 | } | |
1277 | ||
c35384fb TT |
1278 | /* See minsyms.h. */ |
1279 | ||
1280 | void | |
1281 | terminate_minimal_symbol_table (struct objfile *objfile) | |
1282 | { | |
1283 | if (! objfile->msymbols) | |
1284 | objfile->msymbols = ((struct minimal_symbol *) | |
1285 | obstack_alloc (&objfile->objfile_obstack, | |
1286 | sizeof (objfile->msymbols[0]))); | |
1287 | ||
1288 | { | |
1289 | struct minimal_symbol *m | |
1290 | = &objfile->msymbols[objfile->minimal_symbol_count]; | |
1291 | ||
1292 | memset (m, 0, sizeof (*m)); | |
1293 | /* Don't rely on these enumeration values being 0's. */ | |
1294 | MSYMBOL_TYPE (m) = mst_unknown; | |
1295 | SYMBOL_SET_LANGUAGE (m, language_unknown); | |
1296 | } | |
1297 | } | |
1298 | ||
c906108c SS |
1299 | /* Sort all the minimal symbols in OBJFILE. */ |
1300 | ||
1301 | void | |
fba45db2 | 1302 | msymbols_sort (struct objfile *objfile) |
c906108c SS |
1303 | { |
1304 | qsort (objfile->msymbols, objfile->minimal_symbol_count, | |
1305 | sizeof (struct minimal_symbol), compare_minimal_symbols); | |
afbb8d7a | 1306 | build_minimal_symbol_hash_tables (objfile); |
c906108c SS |
1307 | } |
1308 | ||
b19686e0 | 1309 | /* See minsyms.h. */ |
c906108c SS |
1310 | |
1311 | struct minimal_symbol * | |
fba45db2 | 1312 | lookup_solib_trampoline_symbol_by_pc (CORE_ADDR pc) |
c906108c | 1313 | { |
2eaf8d2a DJ |
1314 | struct obj_section *section = find_pc_section (pc); |
1315 | struct minimal_symbol *msymbol; | |
1316 | ||
1317 | if (section == NULL) | |
1318 | return NULL; | |
714835d5 | 1319 | msymbol = lookup_minimal_symbol_by_pc_section_1 (pc, section, 1); |
c906108c SS |
1320 | |
1321 | if (msymbol != NULL && MSYMBOL_TYPE (msymbol) == mst_solib_trampoline) | |
1322 | return msymbol; | |
1323 | return NULL; | |
1324 | } | |
1325 | ||
1326 | /* If PC is in a shared library trampoline code stub, return the | |
1327 | address of the `real' function belonging to the stub. | |
1328 | Return 0 if PC is not in a trampoline code stub or if the real | |
1329 | function is not found in the minimal symbol table. | |
1330 | ||
1331 | We may fail to find the right function if a function with the | |
1332 | same name is defined in more than one shared library, but this | |
025bb325 | 1333 | is considered bad programming style. We could return 0 if we find |
c906108c SS |
1334 | a duplicate function in case this matters someday. */ |
1335 | ||
1336 | CORE_ADDR | |
52f729a7 | 1337 | find_solib_trampoline_target (struct frame_info *frame, CORE_ADDR pc) |
c906108c SS |
1338 | { |
1339 | struct objfile *objfile; | |
1340 | struct minimal_symbol *msymbol; | |
1341 | struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc); | |
1342 | ||
1343 | if (tsymbol != NULL) | |
1344 | { | |
1345 | ALL_MSYMBOLS (objfile, msymbol) | |
c5aa993b | 1346 | { |
0875794a JK |
1347 | if ((MSYMBOL_TYPE (msymbol) == mst_text |
1348 | || MSYMBOL_TYPE (msymbol) == mst_text_gnu_ifunc) | |
6314a349 AC |
1349 | && strcmp (SYMBOL_LINKAGE_NAME (msymbol), |
1350 | SYMBOL_LINKAGE_NAME (tsymbol)) == 0) | |
c5aa993b | 1351 | return SYMBOL_VALUE_ADDRESS (msymbol); |
42848c96 UW |
1352 | |
1353 | /* Also handle minimal symbols pointing to function descriptors. */ | |
1354 | if (MSYMBOL_TYPE (msymbol) == mst_data | |
1355 | && strcmp (SYMBOL_LINKAGE_NAME (msymbol), | |
1356 | SYMBOL_LINKAGE_NAME (tsymbol)) == 0) | |
1357 | { | |
1358 | CORE_ADDR func; | |
b8d56208 | 1359 | |
42848c96 UW |
1360 | func = gdbarch_convert_from_func_ptr_addr |
1361 | (get_objfile_arch (objfile), | |
1362 | SYMBOL_VALUE_ADDRESS (msymbol), | |
1363 | ¤t_target); | |
1364 | ||
1365 | /* Ignore data symbols that are not function descriptors. */ | |
1366 | if (func != SYMBOL_VALUE_ADDRESS (msymbol)) | |
1367 | return func; | |
1368 | } | |
c5aa993b | 1369 | } |
c906108c SS |
1370 | } |
1371 | return 0; | |
1372 | } |