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c906108c SS |
1 | /* GDB routines for manipulating the minimal symbol tables. |
2 | Copyright 1992, 93, 94, 96, 97, 1998 Free Software Foundation, Inc. | |
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 | |
9 | the Free Software Foundation; either version 2 of the License, or | |
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 JM |
17 | You should have received a copy of the GNU General Public License |
18 | along with this program; if not, write to the Free Software | |
19 | Foundation, Inc., 59 Temple Place - Suite 330, | |
20 | Boston, MA 02111-1307, USA. */ | |
c906108c SS |
21 | |
22 | ||
23 | /* This file contains support routines for creating, manipulating, and | |
24 | destroying minimal symbol tables. | |
25 | ||
26 | Minimal symbol tables are used to hold some very basic information about | |
27 | all defined global symbols (text, data, bss, abs, etc). The only two | |
28 | required pieces of information are the symbol's name and the address | |
29 | associated with that symbol. | |
30 | ||
31 | In many cases, even if a file was compiled with no special options for | |
32 | debugging at all, as long as was not stripped it will contain sufficient | |
33 | information to build useful minimal symbol tables using this structure. | |
c5aa993b | 34 | |
c906108c SS |
35 | Even when a file contains enough debugging information to build a full |
36 | symbol table, these minimal symbols are still useful for quickly mapping | |
37 | between names and addresses, and vice versa. They are also sometimes used | |
38 | to figure out what full symbol table entries need to be read in. */ | |
39 | ||
40 | ||
41 | #include "defs.h" | |
9227b5eb | 42 | #include <ctype.h> |
c906108c SS |
43 | #include "gdb_string.h" |
44 | #include "symtab.h" | |
45 | #include "bfd.h" | |
46 | #include "symfile.h" | |
47 | #include "objfiles.h" | |
48 | #include "demangle.h" | |
49 | #include "gdb-stabs.h" | |
50 | ||
51 | /* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE. | |
52 | At the end, copy them all into one newly allocated location on an objfile's | |
53 | symbol obstack. */ | |
54 | ||
55 | #define BUNCH_SIZE 127 | |
56 | ||
57 | struct msym_bunch | |
c5aa993b JM |
58 | { |
59 | struct msym_bunch *next; | |
60 | struct minimal_symbol contents[BUNCH_SIZE]; | |
61 | }; | |
c906108c SS |
62 | |
63 | /* Bunch currently being filled up. | |
64 | The next field points to chain of filled bunches. */ | |
65 | ||
66 | static struct msym_bunch *msym_bunch; | |
67 | ||
68 | /* Number of slots filled in current bunch. */ | |
69 | ||
70 | static int msym_bunch_index; | |
71 | ||
72 | /* Total number of minimal symbols recorded so far for the objfile. */ | |
73 | ||
74 | static int msym_count; | |
75 | ||
76 | /* Prototypes for local functions. */ | |
77 | ||
78 | static int | |
79 | compare_minimal_symbols PARAMS ((const void *, const void *)); | |
80 | ||
81 | static int | |
9227b5eb JB |
82 | compact_minimal_symbols PARAMS ((struct minimal_symbol *, int, |
83 | struct objfile *)); | |
84 | ||
85 | /* Compute a hash code based using the same criteria as `strcmp_iw'. */ | |
86 | ||
87 | unsigned int | |
88 | msymbol_hash_iw (const char *string) | |
89 | { | |
90 | unsigned int hash = 0; | |
91 | while (*string && *string != '(') | |
92 | { | |
93 | while (isspace (*string)) | |
94 | ++string; | |
95 | if (*string && *string != '(') | |
96 | hash = (31 * hash) + *string; | |
97 | ++string; | |
98 | } | |
99 | return hash % MINIMAL_SYMBOL_HASH_SIZE; | |
100 | } | |
101 | ||
102 | /* Compute a hash code for a string. */ | |
103 | ||
104 | unsigned int | |
105 | msymbol_hash (const char *string) | |
106 | { | |
107 | unsigned int hash = 0; | |
108 | for (; *string; ++string) | |
109 | hash = (31 * hash) + *string; | |
110 | return hash % MINIMAL_SYMBOL_HASH_SIZE; | |
111 | } | |
112 | ||
113 | /* Add the minimal symbol SYM to an objfile's minsym hash table, TABLE. */ | |
114 | void | |
115 | add_minsym_to_hash_table (struct minimal_symbol *sym, | |
116 | struct minimal_symbol **table) | |
117 | { | |
118 | if (sym->hash_next == NULL) | |
119 | { | |
120 | unsigned int hash = msymbol_hash (SYMBOL_NAME (sym)); | |
121 | sym->hash_next = table[hash]; | |
122 | table[hash] = sym; | |
123 | } | |
124 | } | |
125 | ||
c906108c SS |
126 | |
127 | /* Look through all the current minimal symbol tables and find the | |
128 | first minimal symbol that matches NAME. If OBJF is non-NULL, limit | |
129 | the search to that objfile. If SFILE is non-NULL, limit the search | |
130 | to that source file. Returns a pointer to the minimal symbol that | |
131 | matches, or NULL if no match is found. | |
132 | ||
133 | Note: One instance where there may be duplicate minimal symbols with | |
134 | the same name is when the symbol tables for a shared library and the | |
135 | symbol tables for an executable contain global symbols with the same | |
136 | names (the dynamic linker deals with the duplication). */ | |
137 | ||
138 | struct minimal_symbol * | |
139 | lookup_minimal_symbol (name, sfile, objf) | |
140 | register const char *name; | |
141 | const char *sfile; | |
142 | struct objfile *objf; | |
143 | { | |
144 | struct objfile *objfile; | |
145 | struct minimal_symbol *msymbol; | |
146 | struct minimal_symbol *found_symbol = NULL; | |
147 | struct minimal_symbol *found_file_symbol = NULL; | |
148 | struct minimal_symbol *trampoline_symbol = NULL; | |
149 | ||
9227b5eb JB |
150 | unsigned int hash = msymbol_hash (name); |
151 | unsigned int dem_hash = msymbol_hash_iw (name); | |
152 | ||
c906108c SS |
153 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING |
154 | if (sfile != NULL) | |
155 | { | |
156 | char *p = strrchr (sfile, '/'); | |
157 | if (p != NULL) | |
158 | sfile = p + 1; | |
159 | } | |
160 | #endif | |
161 | ||
162 | for (objfile = object_files; | |
163 | objfile != NULL && found_symbol == NULL; | |
c5aa993b | 164 | objfile = objfile->next) |
c906108c SS |
165 | { |
166 | if (objf == NULL || objf == objfile) | |
167 | { | |
9227b5eb JB |
168 | /* Do two passes: the first over the ordinary hash table, |
169 | and the second over the demangled hash table. */ | |
170 | int pass = 1; | |
171 | ||
172 | msymbol = objfile->msymbol_hash[hash]; | |
173 | ||
174 | while (msymbol != NULL && found_symbol == NULL) | |
c906108c SS |
175 | { |
176 | if (SYMBOL_MATCHES_NAME (msymbol, name)) | |
177 | { | |
178 | switch (MSYMBOL_TYPE (msymbol)) | |
179 | { | |
180 | case mst_file_text: | |
181 | case mst_file_data: | |
182 | case mst_file_bss: | |
183 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
184 | if (sfile == NULL || STREQ (msymbol->filename, sfile)) | |
185 | found_file_symbol = msymbol; | |
186 | #else | |
187 | /* We have neither the ability nor the need to | |
c5aa993b JM |
188 | deal with the SFILE parameter. If we find |
189 | more than one symbol, just return the latest | |
190 | one (the user can't expect useful behavior in | |
191 | that case). */ | |
c906108c SS |
192 | found_file_symbol = msymbol; |
193 | #endif | |
194 | break; | |
195 | ||
c5aa993b | 196 | case mst_solib_trampoline: |
c906108c SS |
197 | |
198 | /* If a trampoline symbol is found, we prefer to | |
c5aa993b JM |
199 | keep looking for the *real* symbol. If the |
200 | actual symbol is not found, then we'll use the | |
201 | trampoline entry. */ | |
c906108c SS |
202 | if (trampoline_symbol == NULL) |
203 | trampoline_symbol = msymbol; | |
204 | break; | |
205 | ||
206 | case mst_unknown: | |
207 | default: | |
208 | found_symbol = msymbol; | |
209 | break; | |
210 | } | |
211 | } | |
9227b5eb JB |
212 | |
213 | /* Find the next symbol on the hash chain. At the end | |
214 | of the first pass, try the demangled hash list. */ | |
215 | if (pass == 1) | |
216 | msymbol = msymbol->hash_next; | |
217 | else | |
218 | msymbol = msymbol->demangled_hash_next; | |
219 | if (msymbol == NULL) | |
220 | { | |
221 | ++pass; | |
222 | if (pass == 2) | |
223 | msymbol = objfile->msymbol_demangled_hash[dem_hash]; | |
224 | } | |
c906108c SS |
225 | } |
226 | } | |
227 | } | |
228 | /* External symbols are best. */ | |
229 | if (found_symbol) | |
230 | return found_symbol; | |
231 | ||
232 | /* File-local symbols are next best. */ | |
233 | if (found_file_symbol) | |
234 | return found_file_symbol; | |
235 | ||
236 | /* Symbols for shared library trampolines are next best. */ | |
237 | if (trampoline_symbol) | |
238 | return trampoline_symbol; | |
239 | ||
240 | return NULL; | |
241 | } | |
242 | ||
243 | /* Look through all the current minimal symbol tables and find the | |
244 | first minimal symbol that matches NAME and of text type. | |
245 | If OBJF is non-NULL, limit | |
246 | the search to that objfile. If SFILE is non-NULL, limit the search | |
247 | to that source file. Returns a pointer to the minimal symbol that | |
248 | matches, or NULL if no match is found. | |
c5aa993b JM |
249 | */ |
250 | ||
c906108c SS |
251 | struct minimal_symbol * |
252 | lookup_minimal_symbol_text (name, sfile, objf) | |
253 | register const char *name; | |
254 | const char *sfile; | |
255 | struct objfile *objf; | |
256 | { | |
257 | struct objfile *objfile; | |
258 | struct minimal_symbol *msymbol; | |
259 | struct minimal_symbol *found_symbol = NULL; | |
260 | struct minimal_symbol *found_file_symbol = NULL; | |
261 | ||
262 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
263 | if (sfile != NULL) | |
264 | { | |
265 | char *p = strrchr (sfile, '/'); | |
266 | if (p != NULL) | |
267 | sfile = p + 1; | |
268 | } | |
269 | #endif | |
270 | ||
271 | for (objfile = object_files; | |
272 | objfile != NULL && found_symbol == NULL; | |
c5aa993b | 273 | objfile = objfile->next) |
c906108c SS |
274 | { |
275 | if (objf == NULL || objf == objfile) | |
276 | { | |
c5aa993b | 277 | for (msymbol = objfile->msymbols; |
c906108c SS |
278 | msymbol != NULL && SYMBOL_NAME (msymbol) != NULL && |
279 | found_symbol == NULL; | |
280 | msymbol++) | |
281 | { | |
c5aa993b | 282 | if (SYMBOL_MATCHES_NAME (msymbol, name) && |
c906108c SS |
283 | (MSYMBOL_TYPE (msymbol) == mst_text || |
284 | MSYMBOL_TYPE (msymbol) == mst_file_text)) | |
285 | { | |
286 | switch (MSYMBOL_TYPE (msymbol)) | |
287 | { | |
288 | case mst_file_text: | |
289 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
290 | if (sfile == NULL || STREQ (msymbol->filename, sfile)) | |
291 | found_file_symbol = msymbol; | |
292 | #else | |
293 | /* We have neither the ability nor the need to | |
c5aa993b JM |
294 | deal with the SFILE parameter. If we find |
295 | more than one symbol, just return the latest | |
296 | one (the user can't expect useful behavior in | |
297 | that case). */ | |
c906108c SS |
298 | found_file_symbol = msymbol; |
299 | #endif | |
300 | break; | |
301 | default: | |
302 | found_symbol = msymbol; | |
303 | break; | |
304 | } | |
305 | } | |
306 | } | |
307 | } | |
308 | } | |
309 | /* External symbols are best. */ | |
310 | if (found_symbol) | |
311 | return found_symbol; | |
312 | ||
313 | /* File-local symbols are next best. */ | |
314 | if (found_file_symbol) | |
315 | return found_file_symbol; | |
316 | ||
317 | return NULL; | |
318 | } | |
319 | ||
320 | /* Look through all the current minimal symbol tables and find the | |
321 | first minimal symbol that matches NAME and of solib trampoline type. | |
322 | If OBJF is non-NULL, limit | |
323 | the search to that objfile. If SFILE is non-NULL, limit the search | |
324 | to that source file. Returns a pointer to the minimal symbol that | |
325 | matches, or NULL if no match is found. | |
c5aa993b JM |
326 | */ |
327 | ||
c906108c SS |
328 | struct minimal_symbol * |
329 | lookup_minimal_symbol_solib_trampoline (name, sfile, objf) | |
330 | register const char *name; | |
331 | const char *sfile; | |
332 | struct objfile *objf; | |
333 | { | |
334 | struct objfile *objfile; | |
335 | struct minimal_symbol *msymbol; | |
336 | struct minimal_symbol *found_symbol = NULL; | |
337 | ||
338 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
339 | if (sfile != NULL) | |
340 | { | |
341 | char *p = strrchr (sfile, '/'); | |
342 | if (p != NULL) | |
343 | sfile = p + 1; | |
344 | } | |
345 | #endif | |
346 | ||
347 | for (objfile = object_files; | |
348 | objfile != NULL && found_symbol == NULL; | |
c5aa993b | 349 | objfile = objfile->next) |
c906108c SS |
350 | { |
351 | if (objf == NULL || objf == objfile) | |
352 | { | |
c5aa993b | 353 | for (msymbol = objfile->msymbols; |
c906108c SS |
354 | msymbol != NULL && SYMBOL_NAME (msymbol) != NULL && |
355 | found_symbol == NULL; | |
356 | msymbol++) | |
357 | { | |
c5aa993b | 358 | if (SYMBOL_MATCHES_NAME (msymbol, name) && |
c906108c SS |
359 | MSYMBOL_TYPE (msymbol) == mst_solib_trampoline) |
360 | return msymbol; | |
361 | } | |
362 | } | |
363 | } | |
364 | ||
365 | return NULL; | |
366 | } | |
367 | ||
368 | ||
369 | /* Search through the minimal symbol table for each objfile and find | |
370 | the symbol whose address is the largest address that is still less | |
371 | than or equal to PC, and matches SECTION (if non-null). Returns a | |
372 | pointer to the minimal symbol if such a symbol is found, or NULL if | |
373 | PC is not in a suitable range. Note that we need to look through | |
374 | ALL the minimal symbol tables before deciding on the symbol that | |
375 | comes closest to the specified PC. This is because objfiles can | |
376 | overlap, for example objfile A has .text at 0x100 and .data at | |
377 | 0x40000 and objfile B has .text at 0x234 and .data at 0x40048. */ | |
378 | ||
379 | struct minimal_symbol * | |
380 | lookup_minimal_symbol_by_pc_section (pc, section) | |
381 | CORE_ADDR pc; | |
382 | asection *section; | |
383 | { | |
384 | int lo; | |
385 | int hi; | |
386 | int new; | |
387 | struct objfile *objfile; | |
388 | struct minimal_symbol *msymbol; | |
389 | struct minimal_symbol *best_symbol = NULL; | |
390 | ||
391 | /* pc has to be in a known section. This ensures that anything beyond | |
392 | the end of the last segment doesn't appear to be part of the last | |
393 | function in the last segment. */ | |
394 | if (find_pc_section (pc) == NULL) | |
395 | return NULL; | |
396 | ||
397 | for (objfile = object_files; | |
398 | objfile != NULL; | |
c5aa993b | 399 | objfile = objfile->next) |
c906108c SS |
400 | { |
401 | /* If this objfile has a minimal symbol table, go search it using | |
c5aa993b JM |
402 | a binary search. Note that a minimal symbol table always consists |
403 | of at least two symbols, a "real" symbol and the terminating | |
404 | "null symbol". If there are no real symbols, then there is no | |
405 | minimal symbol table at all. */ | |
c906108c | 406 | |
c5aa993b | 407 | if ((msymbol = objfile->msymbols) != NULL) |
c906108c SS |
408 | { |
409 | lo = 0; | |
c5aa993b | 410 | hi = objfile->minimal_symbol_count - 1; |
c906108c SS |
411 | |
412 | /* This code assumes that the minimal symbols are sorted by | |
413 | ascending address values. If the pc value is greater than or | |
414 | equal to the first symbol's address, then some symbol in this | |
415 | minimal symbol table is a suitable candidate for being the | |
416 | "best" symbol. This includes the last real symbol, for cases | |
417 | where the pc value is larger than any address in this vector. | |
418 | ||
419 | By iterating until the address associated with the current | |
420 | hi index (the endpoint of the test interval) is less than | |
421 | or equal to the desired pc value, we accomplish two things: | |
422 | (1) the case where the pc value is larger than any minimal | |
423 | symbol address is trivially solved, (2) the address associated | |
424 | with the hi index is always the one we want when the interation | |
425 | terminates. In essence, we are iterating the test interval | |
426 | down until the pc value is pushed out of it from the high end. | |
427 | ||
428 | Warning: this code is trickier than it would appear at first. */ | |
429 | ||
430 | /* Should also require that pc is <= end of objfile. FIXME! */ | |
431 | if (pc >= SYMBOL_VALUE_ADDRESS (&msymbol[lo])) | |
432 | { | |
433 | while (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) > pc) | |
434 | { | |
435 | /* pc is still strictly less than highest address */ | |
436 | /* Note "new" will always be >= lo */ | |
437 | new = (lo + hi) / 2; | |
438 | if ((SYMBOL_VALUE_ADDRESS (&msymbol[new]) >= pc) || | |
439 | (lo == new)) | |
440 | { | |
441 | hi = new; | |
442 | } | |
443 | else | |
444 | { | |
445 | lo = new; | |
446 | } | |
447 | } | |
448 | ||
449 | /* If we have multiple symbols at the same address, we want | |
c5aa993b JM |
450 | hi to point to the last one. That way we can find the |
451 | right symbol if it has an index greater than hi. */ | |
452 | while (hi < objfile->minimal_symbol_count - 1 | |
c906108c | 453 | && (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) |
c5aa993b | 454 | == SYMBOL_VALUE_ADDRESS (&msymbol[hi + 1]))) |
c906108c SS |
455 | hi++; |
456 | ||
457 | /* The minimal symbol indexed by hi now is the best one in this | |
c5aa993b JM |
458 | objfile's minimal symbol table. See if it is the best one |
459 | overall. */ | |
c906108c SS |
460 | |
461 | /* Skip any absolute symbols. This is apparently what adb | |
c5aa993b JM |
462 | and dbx do, and is needed for the CM-5. There are two |
463 | known possible problems: (1) on ELF, apparently end, edata, | |
464 | etc. are absolute. Not sure ignoring them here is a big | |
465 | deal, but if we want to use them, the fix would go in | |
466 | elfread.c. (2) I think shared library entry points on the | |
467 | NeXT are absolute. If we want special handling for this | |
468 | it probably should be triggered by a special | |
469 | mst_abs_or_lib or some such. */ | |
c906108c SS |
470 | while (hi >= 0 |
471 | && msymbol[hi].type == mst_abs) | |
472 | --hi; | |
473 | ||
474 | /* If "section" specified, skip any symbol from wrong section */ | |
475 | /* This is the new code that distinguishes it from the old function */ | |
476 | if (section) | |
477 | while (hi >= 0 | |
478 | && SYMBOL_BFD_SECTION (&msymbol[hi]) != section) | |
479 | --hi; | |
480 | ||
481 | if (hi >= 0 | |
482 | && ((best_symbol == NULL) || | |
c5aa993b | 483 | (SYMBOL_VALUE_ADDRESS (best_symbol) < |
c906108c SS |
484 | SYMBOL_VALUE_ADDRESS (&msymbol[hi])))) |
485 | { | |
486 | best_symbol = &msymbol[hi]; | |
487 | } | |
488 | } | |
489 | } | |
490 | } | |
491 | return (best_symbol); | |
492 | } | |
493 | ||
494 | /* Backward compatibility: search through the minimal symbol table | |
495 | for a matching PC (no section given) */ | |
496 | ||
497 | struct minimal_symbol * | |
498 | lookup_minimal_symbol_by_pc (pc) | |
499 | CORE_ADDR pc; | |
500 | { | |
501 | return lookup_minimal_symbol_by_pc_section (pc, find_pc_mapped_section (pc)); | |
502 | } | |
503 | ||
504 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
505 | CORE_ADDR | |
c2c6d25f | 506 | find_stab_function_addr (namestring, filename, objfile) |
c906108c | 507 | char *namestring; |
c2c6d25f | 508 | char *filename; |
c906108c SS |
509 | struct objfile *objfile; |
510 | { | |
511 | struct minimal_symbol *msym; | |
512 | char *p; | |
513 | int n; | |
514 | ||
515 | p = strchr (namestring, ':'); | |
516 | if (p == NULL) | |
517 | p = namestring; | |
518 | n = p - namestring; | |
519 | p = alloca (n + 2); | |
520 | strncpy (p, namestring, n); | |
521 | p[n] = 0; | |
522 | ||
c2c6d25f | 523 | msym = lookup_minimal_symbol (p, filename, objfile); |
c906108c SS |
524 | if (msym == NULL) |
525 | { | |
526 | /* Sun Fortran appends an underscore to the minimal symbol name, | |
c5aa993b JM |
527 | try again with an appended underscore if the minimal symbol |
528 | was not found. */ | |
c906108c SS |
529 | p[n] = '_'; |
530 | p[n + 1] = 0; | |
c2c6d25f | 531 | msym = lookup_minimal_symbol (p, filename, objfile); |
c906108c | 532 | } |
c2c6d25f JM |
533 | |
534 | if (msym == NULL && filename != NULL) | |
535 | { | |
536 | /* Try again without the filename. */ | |
537 | p[n] = 0; | |
538 | msym = lookup_minimal_symbol (p, 0, objfile); | |
539 | } | |
540 | if (msym == NULL && filename != NULL) | |
541 | { | |
542 | /* And try again for Sun Fortran, but without the filename. */ | |
543 | p[n] = '_'; | |
544 | p[n + 1] = 0; | |
545 | msym = lookup_minimal_symbol (p, 0, objfile); | |
546 | } | |
547 | ||
c906108c SS |
548 | return msym == NULL ? 0 : SYMBOL_VALUE_ADDRESS (msym); |
549 | } | |
550 | #endif /* SOFUN_ADDRESS_MAYBE_MISSING */ | |
c906108c | 551 | \f |
c5aa993b | 552 | |
c906108c SS |
553 | /* Return leading symbol character for a BFD. If BFD is NULL, |
554 | return the leading symbol character from the main objfile. */ | |
555 | ||
556 | static int get_symbol_leading_char PARAMS ((bfd *)); | |
557 | ||
558 | static int | |
559 | get_symbol_leading_char (abfd) | |
c5aa993b | 560 | bfd *abfd; |
c906108c SS |
561 | { |
562 | if (abfd != NULL) | |
563 | return bfd_get_symbol_leading_char (abfd); | |
564 | if (symfile_objfile != NULL && symfile_objfile->obfd != NULL) | |
565 | return bfd_get_symbol_leading_char (symfile_objfile->obfd); | |
566 | return 0; | |
567 | } | |
568 | ||
569 | /* Prepare to start collecting minimal symbols. Note that presetting | |
570 | msym_bunch_index to BUNCH_SIZE causes the first call to save a minimal | |
571 | symbol to allocate the memory for the first bunch. */ | |
572 | ||
573 | void | |
574 | init_minimal_symbol_collection () | |
575 | { | |
576 | msym_count = 0; | |
577 | msym_bunch = NULL; | |
578 | msym_bunch_index = BUNCH_SIZE; | |
579 | } | |
580 | ||
581 | void | |
582 | prim_record_minimal_symbol (name, address, ms_type, objfile) | |
583 | const char *name; | |
584 | CORE_ADDR address; | |
585 | enum minimal_symbol_type ms_type; | |
586 | struct objfile *objfile; | |
587 | { | |
588 | int section; | |
589 | ||
590 | switch (ms_type) | |
591 | { | |
592 | case mst_text: | |
593 | case mst_file_text: | |
594 | case mst_solib_trampoline: | |
595 | section = SECT_OFF_TEXT; | |
596 | break; | |
597 | case mst_data: | |
598 | case mst_file_data: | |
599 | section = SECT_OFF_DATA; | |
600 | break; | |
601 | case mst_bss: | |
602 | case mst_file_bss: | |
603 | section = SECT_OFF_BSS; | |
604 | break; | |
605 | default: | |
606 | section = -1; | |
607 | } | |
608 | ||
609 | prim_record_minimal_symbol_and_info (name, address, ms_type, | |
610 | NULL, section, NULL, objfile); | |
611 | } | |
612 | ||
613 | /* Record a minimal symbol in the msym bunches. Returns the symbol | |
614 | newly created. */ | |
615 | ||
616 | struct minimal_symbol * | |
617 | prim_record_minimal_symbol_and_info (name, address, ms_type, info, section, | |
618 | bfd_section, objfile) | |
619 | const char *name; | |
620 | CORE_ADDR address; | |
621 | enum minimal_symbol_type ms_type; | |
622 | char *info; | |
623 | int section; | |
624 | asection *bfd_section; | |
625 | struct objfile *objfile; | |
626 | { | |
627 | register struct msym_bunch *new; | |
628 | register struct minimal_symbol *msymbol; | |
629 | ||
630 | if (ms_type == mst_file_text) | |
631 | { | |
632 | /* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into | |
c5aa993b JM |
633 | the minimal symbols, because if there is also another symbol |
634 | at the same address (e.g. the first function of the file), | |
635 | lookup_minimal_symbol_by_pc would have no way of getting the | |
636 | right one. */ | |
c906108c SS |
637 | if (name[0] == 'g' |
638 | && (strcmp (name, GCC_COMPILED_FLAG_SYMBOL) == 0 | |
639 | || strcmp (name, GCC2_COMPILED_FLAG_SYMBOL) == 0)) | |
640 | return (NULL); | |
641 | ||
642 | { | |
643 | const char *tempstring = name; | |
644 | if (tempstring[0] == get_symbol_leading_char (objfile->obfd)) | |
645 | ++tempstring; | |
646 | if (STREQN (tempstring, "__gnu_compiled", 14)) | |
647 | return (NULL); | |
648 | } | |
649 | } | |
650 | ||
651 | if (msym_bunch_index == BUNCH_SIZE) | |
652 | { | |
653 | new = (struct msym_bunch *) xmalloc (sizeof (struct msym_bunch)); | |
654 | msym_bunch_index = 0; | |
c5aa993b | 655 | new->next = msym_bunch; |
c906108c SS |
656 | msym_bunch = new; |
657 | } | |
c5aa993b | 658 | msymbol = &msym_bunch->contents[msym_bunch_index]; |
c906108c SS |
659 | SYMBOL_NAME (msymbol) = obsavestring ((char *) name, strlen (name), |
660 | &objfile->symbol_obstack); | |
661 | SYMBOL_INIT_LANGUAGE_SPECIFIC (msymbol, language_unknown); | |
662 | SYMBOL_VALUE_ADDRESS (msymbol) = address; | |
663 | SYMBOL_SECTION (msymbol) = section; | |
664 | SYMBOL_BFD_SECTION (msymbol) = bfd_section; | |
665 | ||
666 | MSYMBOL_TYPE (msymbol) = ms_type; | |
667 | /* FIXME: This info, if it remains, needs its own field. */ | |
c5aa993b | 668 | MSYMBOL_INFO (msymbol) = info; /* FIXME! */ |
9227b5eb JB |
669 | |
670 | msymbol->hash_next = NULL; | |
671 | msymbol->demangled_hash_next = NULL; | |
672 | ||
c906108c SS |
673 | msym_bunch_index++; |
674 | msym_count++; | |
675 | OBJSTAT (objfile, n_minsyms++); | |
676 | return msymbol; | |
677 | } | |
678 | ||
679 | /* Compare two minimal symbols by address and return a signed result based | |
680 | on unsigned comparisons, so that we sort into unsigned numeric order. | |
681 | Within groups with the same address, sort by name. */ | |
682 | ||
683 | static int | |
684 | compare_minimal_symbols (fn1p, fn2p) | |
685 | const PTR fn1p; | |
686 | const PTR fn2p; | |
687 | { | |
688 | register const struct minimal_symbol *fn1; | |
689 | register const struct minimal_symbol *fn2; | |
690 | ||
691 | fn1 = (const struct minimal_symbol *) fn1p; | |
692 | fn2 = (const struct minimal_symbol *) fn2p; | |
693 | ||
694 | if (SYMBOL_VALUE_ADDRESS (fn1) < SYMBOL_VALUE_ADDRESS (fn2)) | |
695 | { | |
c5aa993b | 696 | return (-1); /* addr 1 is less than addr 2 */ |
c906108c SS |
697 | } |
698 | else if (SYMBOL_VALUE_ADDRESS (fn1) > SYMBOL_VALUE_ADDRESS (fn2)) | |
699 | { | |
c5aa993b | 700 | return (1); /* addr 1 is greater than addr 2 */ |
c906108c | 701 | } |
c5aa993b JM |
702 | else |
703 | /* addrs are equal: sort by name */ | |
c906108c SS |
704 | { |
705 | char *name1 = SYMBOL_NAME (fn1); | |
706 | char *name2 = SYMBOL_NAME (fn2); | |
707 | ||
708 | if (name1 && name2) /* both have names */ | |
709 | return strcmp (name1, name2); | |
710 | else if (name2) | |
c5aa993b JM |
711 | return 1; /* fn1 has no name, so it is "less" */ |
712 | else if (name1) /* fn2 has no name, so it is "less" */ | |
c906108c SS |
713 | return -1; |
714 | else | |
c5aa993b | 715 | return (0); /* neither has a name, so they're equal. */ |
c906108c SS |
716 | } |
717 | } | |
718 | ||
719 | /* Discard the currently collected minimal symbols, if any. If we wish | |
720 | to save them for later use, we must have already copied them somewhere | |
721 | else before calling this function. | |
722 | ||
723 | FIXME: We could allocate the minimal symbol bunches on their own | |
724 | obstack and then simply blow the obstack away when we are done with | |
725 | it. Is it worth the extra trouble though? */ | |
726 | ||
727 | /* ARGSUSED */ | |
728 | void | |
729 | discard_minimal_symbols (foo) | |
730 | int foo; | |
731 | { | |
732 | register struct msym_bunch *next; | |
733 | ||
734 | while (msym_bunch != NULL) | |
735 | { | |
c5aa993b JM |
736 | next = msym_bunch->next; |
737 | free ((PTR) msym_bunch); | |
c906108c SS |
738 | msym_bunch = next; |
739 | } | |
740 | } | |
741 | ||
9227b5eb | 742 | |
c906108c SS |
743 | /* Compact duplicate entries out of a minimal symbol table by walking |
744 | through the table and compacting out entries with duplicate addresses | |
745 | and matching names. Return the number of entries remaining. | |
746 | ||
747 | On entry, the table resides between msymbol[0] and msymbol[mcount]. | |
748 | On exit, it resides between msymbol[0] and msymbol[result_count]. | |
749 | ||
750 | When files contain multiple sources of symbol information, it is | |
751 | possible for the minimal symbol table to contain many duplicate entries. | |
752 | As an example, SVR4 systems use ELF formatted object files, which | |
753 | usually contain at least two different types of symbol tables (a | |
754 | standard ELF one and a smaller dynamic linking table), as well as | |
755 | DWARF debugging information for files compiled with -g. | |
756 | ||
757 | Without compacting, the minimal symbol table for gdb itself contains | |
758 | over a 1000 duplicates, about a third of the total table size. Aside | |
759 | from the potential trap of not noticing that two successive entries | |
760 | identify the same location, this duplication impacts the time required | |
761 | to linearly scan the table, which is done in a number of places. So we | |
762 | just do one linear scan here and toss out the duplicates. | |
763 | ||
764 | Note that we are not concerned here about recovering the space that | |
765 | is potentially freed up, because the strings themselves are allocated | |
766 | on the symbol_obstack, and will get automatically freed when the symbol | |
767 | table is freed. The caller can free up the unused minimal symbols at | |
768 | the end of the compacted region if their allocation strategy allows it. | |
769 | ||
770 | Also note we only go up to the next to last entry within the loop | |
771 | and then copy the last entry explicitly after the loop terminates. | |
772 | ||
773 | Since the different sources of information for each symbol may | |
774 | have different levels of "completeness", we may have duplicates | |
775 | that have one entry with type "mst_unknown" and the other with a | |
776 | known type. So if the one we are leaving alone has type mst_unknown, | |
777 | overwrite its type with the type from the one we are compacting out. */ | |
778 | ||
779 | static int | |
9227b5eb | 780 | compact_minimal_symbols (msymbol, mcount, objfile) |
c906108c SS |
781 | struct minimal_symbol *msymbol; |
782 | int mcount; | |
9227b5eb | 783 | struct objfile *objfile; |
c906108c SS |
784 | { |
785 | struct minimal_symbol *copyfrom; | |
786 | struct minimal_symbol *copyto; | |
787 | ||
788 | if (mcount > 0) | |
789 | { | |
790 | copyfrom = copyto = msymbol; | |
791 | while (copyfrom < msymbol + mcount - 1) | |
792 | { | |
c5aa993b | 793 | if (SYMBOL_VALUE_ADDRESS (copyfrom) == |
c906108c SS |
794 | SYMBOL_VALUE_ADDRESS ((copyfrom + 1)) && |
795 | (STREQ (SYMBOL_NAME (copyfrom), SYMBOL_NAME ((copyfrom + 1))))) | |
796 | { | |
c5aa993b | 797 | if (MSYMBOL_TYPE ((copyfrom + 1)) == mst_unknown) |
c906108c SS |
798 | { |
799 | MSYMBOL_TYPE ((copyfrom + 1)) = MSYMBOL_TYPE (copyfrom); | |
800 | } | |
801 | copyfrom++; | |
802 | } | |
803 | else | |
804 | { | |
805 | *copyto++ = *copyfrom++; | |
9227b5eb JB |
806 | |
807 | add_minsym_to_hash_table (copyto - 1, objfile->msymbol_hash); | |
c906108c SS |
808 | } |
809 | } | |
810 | *copyto++ = *copyfrom++; | |
811 | mcount = copyto - msymbol; | |
812 | } | |
813 | return (mcount); | |
814 | } | |
815 | ||
816 | /* Add the minimal symbols in the existing bunches to the objfile's official | |
817 | minimal symbol table. In most cases there is no minimal symbol table yet | |
818 | for this objfile, and the existing bunches are used to create one. Once | |
819 | in a while (for shared libraries for example), we add symbols (e.g. common | |
820 | symbols) to an existing objfile. | |
821 | ||
822 | Because of the way minimal symbols are collected, we generally have no way | |
823 | of knowing what source language applies to any particular minimal symbol. | |
824 | Specifically, we have no way of knowing if the minimal symbol comes from a | |
825 | C++ compilation unit or not. So for the sake of supporting cached | |
826 | demangled C++ names, we have no choice but to try and demangle each new one | |
827 | that comes in. If the demangling succeeds, then we assume it is a C++ | |
828 | symbol and set the symbol's language and demangled name fields | |
829 | appropriately. Note that in order to avoid unnecessary demanglings, and | |
830 | allocating obstack space that subsequently can't be freed for the demangled | |
831 | names, we mark all newly added symbols with language_auto. After | |
832 | compaction of the minimal symbols, we go back and scan the entire minimal | |
833 | symbol table looking for these new symbols. For each new symbol we attempt | |
834 | to demangle it, and if successful, record it as a language_cplus symbol | |
835 | and cache the demangled form on the symbol obstack. Symbols which don't | |
836 | demangle are marked as language_unknown symbols, which inhibits future | |
837 | attempts to demangle them if we later add more minimal symbols. */ | |
838 | ||
839 | void | |
840 | install_minimal_symbols (objfile) | |
841 | struct objfile *objfile; | |
842 | { | |
843 | register int bindex; | |
844 | register int mcount; | |
845 | register struct msym_bunch *bunch; | |
846 | register struct minimal_symbol *msymbols; | |
847 | int alloc_count; | |
848 | register char leading_char; | |
849 | ||
850 | if (msym_count > 0) | |
851 | { | |
852 | /* Allocate enough space in the obstack, into which we will gather the | |
c5aa993b JM |
853 | bunches of new and existing minimal symbols, sort them, and then |
854 | compact out the duplicate entries. Once we have a final table, | |
855 | we will give back the excess space. */ | |
c906108c SS |
856 | |
857 | alloc_count = msym_count + objfile->minimal_symbol_count + 1; | |
858 | obstack_blank (&objfile->symbol_obstack, | |
859 | alloc_count * sizeof (struct minimal_symbol)); | |
860 | msymbols = (struct minimal_symbol *) | |
c5aa993b | 861 | obstack_base (&objfile->symbol_obstack); |
c906108c SS |
862 | |
863 | /* Copy in the existing minimal symbols, if there are any. */ | |
864 | ||
865 | if (objfile->minimal_symbol_count) | |
c5aa993b JM |
866 | memcpy ((char *) msymbols, (char *) objfile->msymbols, |
867 | objfile->minimal_symbol_count * sizeof (struct minimal_symbol)); | |
c906108c SS |
868 | |
869 | /* Walk through the list of minimal symbol bunches, adding each symbol | |
c5aa993b JM |
870 | to the new contiguous array of symbols. Note that we start with the |
871 | current, possibly partially filled bunch (thus we use the current | |
872 | msym_bunch_index for the first bunch we copy over), and thereafter | |
873 | each bunch is full. */ | |
874 | ||
c906108c SS |
875 | mcount = objfile->minimal_symbol_count; |
876 | leading_char = get_symbol_leading_char (objfile->obfd); | |
c5aa993b JM |
877 | |
878 | for (bunch = msym_bunch; bunch != NULL; bunch = bunch->next) | |
c906108c SS |
879 | { |
880 | for (bindex = 0; bindex < msym_bunch_index; bindex++, mcount++) | |
881 | { | |
c5aa993b | 882 | msymbols[mcount] = bunch->contents[bindex]; |
c906108c SS |
883 | SYMBOL_LANGUAGE (&msymbols[mcount]) = language_auto; |
884 | if (SYMBOL_NAME (&msymbols[mcount])[0] == leading_char) | |
885 | { | |
c5aa993b | 886 | SYMBOL_NAME (&msymbols[mcount])++; |
c906108c SS |
887 | } |
888 | } | |
889 | msym_bunch_index = BUNCH_SIZE; | |
890 | } | |
891 | ||
892 | /* Sort the minimal symbols by address. */ | |
c5aa993b | 893 | |
c906108c SS |
894 | qsort (msymbols, mcount, sizeof (struct minimal_symbol), |
895 | compare_minimal_symbols); | |
c5aa993b | 896 | |
c906108c | 897 | /* Compact out any duplicates, and free up whatever space we are |
c5aa993b JM |
898 | no longer using. */ |
899 | ||
9227b5eb | 900 | mcount = compact_minimal_symbols (msymbols, mcount, objfile); |
c906108c SS |
901 | |
902 | obstack_blank (&objfile->symbol_obstack, | |
c5aa993b | 903 | (mcount + 1 - alloc_count) * sizeof (struct minimal_symbol)); |
c906108c SS |
904 | msymbols = (struct minimal_symbol *) |
905 | obstack_finish (&objfile->symbol_obstack); | |
906 | ||
907 | /* We also terminate the minimal symbol table with a "null symbol", | |
c5aa993b JM |
908 | which is *not* included in the size of the table. This makes it |
909 | easier to find the end of the table when we are handed a pointer | |
910 | to some symbol in the middle of it. Zero out the fields in the | |
911 | "null symbol" allocated at the end of the array. Note that the | |
912 | symbol count does *not* include this null symbol, which is why it | |
913 | is indexed by mcount and not mcount-1. */ | |
c906108c SS |
914 | |
915 | SYMBOL_NAME (&msymbols[mcount]) = NULL; | |
916 | SYMBOL_VALUE_ADDRESS (&msymbols[mcount]) = 0; | |
917 | MSYMBOL_INFO (&msymbols[mcount]) = NULL; | |
918 | MSYMBOL_TYPE (&msymbols[mcount]) = mst_unknown; | |
919 | SYMBOL_INIT_LANGUAGE_SPECIFIC (&msymbols[mcount], language_unknown); | |
920 | ||
921 | /* Attach the minimal symbol table to the specified objfile. | |
c5aa993b JM |
922 | The strings themselves are also located in the symbol_obstack |
923 | of this objfile. */ | |
c906108c | 924 | |
c5aa993b JM |
925 | objfile->minimal_symbol_count = mcount; |
926 | objfile->msymbols = msymbols; | |
c906108c SS |
927 | |
928 | /* Now walk through all the minimal symbols, selecting the newly added | |
c5aa993b | 929 | ones and attempting to cache their C++ demangled names. */ |
c906108c | 930 | |
c5aa993b | 931 | for (; mcount-- > 0; msymbols++) |
c906108c SS |
932 | { |
933 | SYMBOL_INIT_DEMANGLED_NAME (msymbols, &objfile->symbol_obstack); | |
9227b5eb JB |
934 | if (SYMBOL_DEMANGLED_NAME (msymbols) != NULL) |
935 | add_minsym_to_hash_table (msymbols, | |
936 | objfile->msymbol_demangled_hash); | |
c906108c SS |
937 | } |
938 | } | |
939 | } | |
940 | ||
941 | /* Sort all the minimal symbols in OBJFILE. */ | |
942 | ||
943 | void | |
944 | msymbols_sort (objfile) | |
945 | struct objfile *objfile; | |
946 | { | |
947 | qsort (objfile->msymbols, objfile->minimal_symbol_count, | |
948 | sizeof (struct minimal_symbol), compare_minimal_symbols); | |
949 | } | |
950 | ||
951 | /* Check if PC is in a shared library trampoline code stub. | |
952 | Return minimal symbol for the trampoline entry or NULL if PC is not | |
953 | in a trampoline code stub. */ | |
954 | ||
955 | struct minimal_symbol * | |
956 | lookup_solib_trampoline_symbol_by_pc (pc) | |
957 | CORE_ADDR pc; | |
958 | { | |
959 | struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (pc); | |
960 | ||
961 | if (msymbol != NULL && MSYMBOL_TYPE (msymbol) == mst_solib_trampoline) | |
962 | return msymbol; | |
963 | return NULL; | |
964 | } | |
965 | ||
966 | /* If PC is in a shared library trampoline code stub, return the | |
967 | address of the `real' function belonging to the stub. | |
968 | Return 0 if PC is not in a trampoline code stub or if the real | |
969 | function is not found in the minimal symbol table. | |
970 | ||
971 | We may fail to find the right function if a function with the | |
972 | same name is defined in more than one shared library, but this | |
973 | is considered bad programming style. We could return 0 if we find | |
974 | a duplicate function in case this matters someday. */ | |
975 | ||
976 | CORE_ADDR | |
977 | find_solib_trampoline_target (pc) | |
978 | CORE_ADDR pc; | |
979 | { | |
980 | struct objfile *objfile; | |
981 | struct minimal_symbol *msymbol; | |
982 | struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc); | |
983 | ||
984 | if (tsymbol != NULL) | |
985 | { | |
986 | ALL_MSYMBOLS (objfile, msymbol) | |
c5aa993b JM |
987 | { |
988 | if (MSYMBOL_TYPE (msymbol) == mst_text | |
989 | && STREQ (SYMBOL_NAME (msymbol), SYMBOL_NAME (tsymbol))) | |
990 | return SYMBOL_VALUE_ADDRESS (msymbol); | |
991 | } | |
c906108c SS |
992 | } |
993 | return 0; | |
994 | } |