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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 | 669 | |
a79dea61 EZ |
670 | /* The hash pointers must be cleared! If they're not, |
671 | MSYMBOL_HASH_ADD will NOT add this msymbol to the hash table. */ | |
9227b5eb JB |
672 | msymbol->hash_next = NULL; |
673 | msymbol->demangled_hash_next = NULL; | |
674 | ||
c906108c SS |
675 | msym_bunch_index++; |
676 | msym_count++; | |
677 | OBJSTAT (objfile, n_minsyms++); | |
678 | return msymbol; | |
679 | } | |
680 | ||
681 | /* Compare two minimal symbols by address and return a signed result based | |
682 | on unsigned comparisons, so that we sort into unsigned numeric order. | |
683 | Within groups with the same address, sort by name. */ | |
684 | ||
685 | static int | |
686 | compare_minimal_symbols (fn1p, fn2p) | |
687 | const PTR fn1p; | |
688 | const PTR fn2p; | |
689 | { | |
690 | register const struct minimal_symbol *fn1; | |
691 | register const struct minimal_symbol *fn2; | |
692 | ||
693 | fn1 = (const struct minimal_symbol *) fn1p; | |
694 | fn2 = (const struct minimal_symbol *) fn2p; | |
695 | ||
696 | if (SYMBOL_VALUE_ADDRESS (fn1) < SYMBOL_VALUE_ADDRESS (fn2)) | |
697 | { | |
c5aa993b | 698 | return (-1); /* addr 1 is less than addr 2 */ |
c906108c SS |
699 | } |
700 | else if (SYMBOL_VALUE_ADDRESS (fn1) > SYMBOL_VALUE_ADDRESS (fn2)) | |
701 | { | |
c5aa993b | 702 | return (1); /* addr 1 is greater than addr 2 */ |
c906108c | 703 | } |
c5aa993b JM |
704 | else |
705 | /* addrs are equal: sort by name */ | |
c906108c SS |
706 | { |
707 | char *name1 = SYMBOL_NAME (fn1); | |
708 | char *name2 = SYMBOL_NAME (fn2); | |
709 | ||
710 | if (name1 && name2) /* both have names */ | |
711 | return strcmp (name1, name2); | |
712 | else if (name2) | |
c5aa993b JM |
713 | return 1; /* fn1 has no name, so it is "less" */ |
714 | else if (name1) /* fn2 has no name, so it is "less" */ | |
c906108c SS |
715 | return -1; |
716 | else | |
c5aa993b | 717 | return (0); /* neither has a name, so they're equal. */ |
c906108c SS |
718 | } |
719 | } | |
720 | ||
721 | /* Discard the currently collected minimal symbols, if any. If we wish | |
722 | to save them for later use, we must have already copied them somewhere | |
723 | else before calling this function. | |
724 | ||
725 | FIXME: We could allocate the minimal symbol bunches on their own | |
726 | obstack and then simply blow the obstack away when we are done with | |
727 | it. Is it worth the extra trouble though? */ | |
728 | ||
729 | /* ARGSUSED */ | |
730 | void | |
731 | discard_minimal_symbols (foo) | |
732 | int foo; | |
733 | { | |
734 | register struct msym_bunch *next; | |
735 | ||
736 | while (msym_bunch != NULL) | |
737 | { | |
c5aa993b JM |
738 | next = msym_bunch->next; |
739 | free ((PTR) msym_bunch); | |
c906108c SS |
740 | msym_bunch = next; |
741 | } | |
742 | } | |
743 | ||
9227b5eb | 744 | |
c906108c SS |
745 | /* Compact duplicate entries out of a minimal symbol table by walking |
746 | through the table and compacting out entries with duplicate addresses | |
747 | and matching names. Return the number of entries remaining. | |
748 | ||
749 | On entry, the table resides between msymbol[0] and msymbol[mcount]. | |
750 | On exit, it resides between msymbol[0] and msymbol[result_count]. | |
751 | ||
752 | When files contain multiple sources of symbol information, it is | |
753 | possible for the minimal symbol table to contain many duplicate entries. | |
754 | As an example, SVR4 systems use ELF formatted object files, which | |
755 | usually contain at least two different types of symbol tables (a | |
756 | standard ELF one and a smaller dynamic linking table), as well as | |
757 | DWARF debugging information for files compiled with -g. | |
758 | ||
759 | Without compacting, the minimal symbol table for gdb itself contains | |
760 | over a 1000 duplicates, about a third of the total table size. Aside | |
761 | from the potential trap of not noticing that two successive entries | |
762 | identify the same location, this duplication impacts the time required | |
763 | to linearly scan the table, which is done in a number of places. So we | |
764 | just do one linear scan here and toss out the duplicates. | |
765 | ||
766 | Note that we are not concerned here about recovering the space that | |
767 | is potentially freed up, because the strings themselves are allocated | |
768 | on the symbol_obstack, and will get automatically freed when the symbol | |
769 | table is freed. The caller can free up the unused minimal symbols at | |
770 | the end of the compacted region if their allocation strategy allows it. | |
771 | ||
772 | Also note we only go up to the next to last entry within the loop | |
773 | and then copy the last entry explicitly after the loop terminates. | |
774 | ||
775 | Since the different sources of information for each symbol may | |
776 | have different levels of "completeness", we may have duplicates | |
777 | that have one entry with type "mst_unknown" and the other with a | |
778 | known type. So if the one we are leaving alone has type mst_unknown, | |
779 | overwrite its type with the type from the one we are compacting out. */ | |
780 | ||
781 | static int | |
9227b5eb | 782 | compact_minimal_symbols (msymbol, mcount, objfile) |
c906108c SS |
783 | struct minimal_symbol *msymbol; |
784 | int mcount; | |
9227b5eb | 785 | struct objfile *objfile; |
c906108c SS |
786 | { |
787 | struct minimal_symbol *copyfrom; | |
788 | struct minimal_symbol *copyto; | |
789 | ||
790 | if (mcount > 0) | |
791 | { | |
792 | copyfrom = copyto = msymbol; | |
793 | while (copyfrom < msymbol + mcount - 1) | |
794 | { | |
c5aa993b | 795 | if (SYMBOL_VALUE_ADDRESS (copyfrom) == |
c906108c SS |
796 | SYMBOL_VALUE_ADDRESS ((copyfrom + 1)) && |
797 | (STREQ (SYMBOL_NAME (copyfrom), SYMBOL_NAME ((copyfrom + 1))))) | |
798 | { | |
c5aa993b | 799 | if (MSYMBOL_TYPE ((copyfrom + 1)) == mst_unknown) |
c906108c SS |
800 | { |
801 | MSYMBOL_TYPE ((copyfrom + 1)) = MSYMBOL_TYPE (copyfrom); | |
802 | } | |
803 | copyfrom++; | |
804 | } | |
805 | else | |
806 | { | |
807 | *copyto++ = *copyfrom++; | |
9227b5eb JB |
808 | |
809 | add_minsym_to_hash_table (copyto - 1, objfile->msymbol_hash); | |
c906108c SS |
810 | } |
811 | } | |
812 | *copyto++ = *copyfrom++; | |
813 | mcount = copyto - msymbol; | |
814 | } | |
815 | return (mcount); | |
816 | } | |
817 | ||
818 | /* Add the minimal symbols in the existing bunches to the objfile's official | |
819 | minimal symbol table. In most cases there is no minimal symbol table yet | |
820 | for this objfile, and the existing bunches are used to create one. Once | |
821 | in a while (for shared libraries for example), we add symbols (e.g. common | |
822 | symbols) to an existing objfile. | |
823 | ||
824 | Because of the way minimal symbols are collected, we generally have no way | |
825 | of knowing what source language applies to any particular minimal symbol. | |
826 | Specifically, we have no way of knowing if the minimal symbol comes from a | |
827 | C++ compilation unit or not. So for the sake of supporting cached | |
828 | demangled C++ names, we have no choice but to try and demangle each new one | |
829 | that comes in. If the demangling succeeds, then we assume it is a C++ | |
830 | symbol and set the symbol's language and demangled name fields | |
831 | appropriately. Note that in order to avoid unnecessary demanglings, and | |
832 | allocating obstack space that subsequently can't be freed for the demangled | |
833 | names, we mark all newly added symbols with language_auto. After | |
834 | compaction of the minimal symbols, we go back and scan the entire minimal | |
835 | symbol table looking for these new symbols. For each new symbol we attempt | |
836 | to demangle it, and if successful, record it as a language_cplus symbol | |
837 | and cache the demangled form on the symbol obstack. Symbols which don't | |
838 | demangle are marked as language_unknown symbols, which inhibits future | |
839 | attempts to demangle them if we later add more minimal symbols. */ | |
840 | ||
841 | void | |
842 | install_minimal_symbols (objfile) | |
843 | struct objfile *objfile; | |
844 | { | |
845 | register int bindex; | |
846 | register int mcount; | |
847 | register struct msym_bunch *bunch; | |
848 | register struct minimal_symbol *msymbols; | |
849 | int alloc_count; | |
850 | register char leading_char; | |
851 | ||
852 | if (msym_count > 0) | |
853 | { | |
854 | /* Allocate enough space in the obstack, into which we will gather the | |
c5aa993b JM |
855 | bunches of new and existing minimal symbols, sort them, and then |
856 | compact out the duplicate entries. Once we have a final table, | |
857 | we will give back the excess space. */ | |
c906108c SS |
858 | |
859 | alloc_count = msym_count + objfile->minimal_symbol_count + 1; | |
860 | obstack_blank (&objfile->symbol_obstack, | |
861 | alloc_count * sizeof (struct minimal_symbol)); | |
862 | msymbols = (struct minimal_symbol *) | |
c5aa993b | 863 | obstack_base (&objfile->symbol_obstack); |
c906108c SS |
864 | |
865 | /* Copy in the existing minimal symbols, if there are any. */ | |
866 | ||
867 | if (objfile->minimal_symbol_count) | |
c5aa993b JM |
868 | memcpy ((char *) msymbols, (char *) objfile->msymbols, |
869 | objfile->minimal_symbol_count * sizeof (struct minimal_symbol)); | |
c906108c SS |
870 | |
871 | /* Walk through the list of minimal symbol bunches, adding each symbol | |
c5aa993b JM |
872 | to the new contiguous array of symbols. Note that we start with the |
873 | current, possibly partially filled bunch (thus we use the current | |
874 | msym_bunch_index for the first bunch we copy over), and thereafter | |
875 | each bunch is full. */ | |
876 | ||
c906108c SS |
877 | mcount = objfile->minimal_symbol_count; |
878 | leading_char = get_symbol_leading_char (objfile->obfd); | |
c5aa993b JM |
879 | |
880 | for (bunch = msym_bunch; bunch != NULL; bunch = bunch->next) | |
c906108c SS |
881 | { |
882 | for (bindex = 0; bindex < msym_bunch_index; bindex++, mcount++) | |
883 | { | |
c5aa993b | 884 | msymbols[mcount] = bunch->contents[bindex]; |
c906108c SS |
885 | SYMBOL_LANGUAGE (&msymbols[mcount]) = language_auto; |
886 | if (SYMBOL_NAME (&msymbols[mcount])[0] == leading_char) | |
887 | { | |
c5aa993b | 888 | SYMBOL_NAME (&msymbols[mcount])++; |
c906108c SS |
889 | } |
890 | } | |
891 | msym_bunch_index = BUNCH_SIZE; | |
892 | } | |
893 | ||
894 | /* Sort the minimal symbols by address. */ | |
c5aa993b | 895 | |
c906108c SS |
896 | qsort (msymbols, mcount, sizeof (struct minimal_symbol), |
897 | compare_minimal_symbols); | |
c5aa993b | 898 | |
c906108c | 899 | /* Compact out any duplicates, and free up whatever space we are |
c5aa993b JM |
900 | no longer using. */ |
901 | ||
9227b5eb | 902 | mcount = compact_minimal_symbols (msymbols, mcount, objfile); |
c906108c SS |
903 | |
904 | obstack_blank (&objfile->symbol_obstack, | |
c5aa993b | 905 | (mcount + 1 - alloc_count) * sizeof (struct minimal_symbol)); |
c906108c SS |
906 | msymbols = (struct minimal_symbol *) |
907 | obstack_finish (&objfile->symbol_obstack); | |
908 | ||
909 | /* We also terminate the minimal symbol table with a "null symbol", | |
c5aa993b JM |
910 | which is *not* included in the size of the table. This makes it |
911 | easier to find the end of the table when we are handed a pointer | |
912 | to some symbol in the middle of it. Zero out the fields in the | |
913 | "null symbol" allocated at the end of the array. Note that the | |
914 | symbol count does *not* include this null symbol, which is why it | |
915 | is indexed by mcount and not mcount-1. */ | |
c906108c SS |
916 | |
917 | SYMBOL_NAME (&msymbols[mcount]) = NULL; | |
918 | SYMBOL_VALUE_ADDRESS (&msymbols[mcount]) = 0; | |
919 | MSYMBOL_INFO (&msymbols[mcount]) = NULL; | |
920 | MSYMBOL_TYPE (&msymbols[mcount]) = mst_unknown; | |
921 | SYMBOL_INIT_LANGUAGE_SPECIFIC (&msymbols[mcount], language_unknown); | |
922 | ||
923 | /* Attach the minimal symbol table to the specified objfile. | |
c5aa993b JM |
924 | The strings themselves are also located in the symbol_obstack |
925 | of this objfile. */ | |
c906108c | 926 | |
c5aa993b JM |
927 | objfile->minimal_symbol_count = mcount; |
928 | objfile->msymbols = msymbols; | |
c906108c SS |
929 | |
930 | /* Now walk through all the minimal symbols, selecting the newly added | |
c5aa993b | 931 | ones and attempting to cache their C++ demangled names. */ |
c906108c | 932 | |
c5aa993b | 933 | for (; mcount-- > 0; msymbols++) |
c906108c SS |
934 | { |
935 | SYMBOL_INIT_DEMANGLED_NAME (msymbols, &objfile->symbol_obstack); | |
9227b5eb JB |
936 | if (SYMBOL_DEMANGLED_NAME (msymbols) != NULL) |
937 | add_minsym_to_hash_table (msymbols, | |
938 | objfile->msymbol_demangled_hash); | |
c906108c SS |
939 | } |
940 | } | |
941 | } | |
942 | ||
943 | /* Sort all the minimal symbols in OBJFILE. */ | |
944 | ||
945 | void | |
946 | msymbols_sort (objfile) | |
947 | struct objfile *objfile; | |
948 | { | |
949 | qsort (objfile->msymbols, objfile->minimal_symbol_count, | |
950 | sizeof (struct minimal_symbol), compare_minimal_symbols); | |
951 | } | |
952 | ||
953 | /* Check if PC is in a shared library trampoline code stub. | |
954 | Return minimal symbol for the trampoline entry or NULL if PC is not | |
955 | in a trampoline code stub. */ | |
956 | ||
957 | struct minimal_symbol * | |
958 | lookup_solib_trampoline_symbol_by_pc (pc) | |
959 | CORE_ADDR pc; | |
960 | { | |
961 | struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (pc); | |
962 | ||
963 | if (msymbol != NULL && MSYMBOL_TYPE (msymbol) == mst_solib_trampoline) | |
964 | return msymbol; | |
965 | return NULL; | |
966 | } | |
967 | ||
968 | /* If PC is in a shared library trampoline code stub, return the | |
969 | address of the `real' function belonging to the stub. | |
970 | Return 0 if PC is not in a trampoline code stub or if the real | |
971 | function is not found in the minimal symbol table. | |
972 | ||
973 | We may fail to find the right function if a function with the | |
974 | same name is defined in more than one shared library, but this | |
975 | is considered bad programming style. We could return 0 if we find | |
976 | a duplicate function in case this matters someday. */ | |
977 | ||
978 | CORE_ADDR | |
979 | find_solib_trampoline_target (pc) | |
980 | CORE_ADDR pc; | |
981 | { | |
982 | struct objfile *objfile; | |
983 | struct minimal_symbol *msymbol; | |
984 | struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc); | |
985 | ||
986 | if (tsymbol != NULL) | |
987 | { | |
988 | ALL_MSYMBOLS (objfile, msymbol) | |
c5aa993b JM |
989 | { |
990 | if (MSYMBOL_TYPE (msymbol) == mst_text | |
991 | && STREQ (SYMBOL_NAME (msymbol), SYMBOL_NAME (tsymbol))) | |
992 | return SYMBOL_VALUE_ADDRESS (msymbol); | |
993 | } | |
c906108c SS |
994 | } |
995 | return 0; | |
996 | } |