1 /* GDB routines for manipulating the minimal symbol tables.
2 Copyright 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
4 Free Software Foundation, Inc.
5 Contributed by Cygnus Support, using pieces from other GDB modules.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
25 /* This file contains support routines for creating, manipulating, and
26 destroying minimal symbol tables.
28 Minimal symbol tables are used to hold some very basic information about
29 all defined global symbols (text, data, bss, abs, etc). The only two
30 required pieces of information are the symbol's name and the address
31 associated with that symbol.
33 In many cases, even if a file was compiled with no special options for
34 debugging at all, as long as was not stripped it will contain sufficient
35 information to build useful minimal symbol tables using this structure.
37 Even when a file contains enough debugging information to build a full
38 symbol table, these minimal symbols are still useful for quickly mapping
39 between names and addresses, and vice versa. They are also sometimes used
40 to figure out what full symbol table entries need to be read in. */
45 #include "gdb_string.h"
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
58 #define BUNCH_SIZE 127
62 struct msym_bunch
*next
;
63 struct minimal_symbol contents
[BUNCH_SIZE
];
66 /* Bunch currently being filled up.
67 The next field points to chain of filled bunches. */
69 static struct msym_bunch
*msym_bunch
;
71 /* Number of slots filled in current bunch. */
73 static int msym_bunch_index
;
75 /* Total number of minimal symbols recorded so far for the objfile. */
77 static int msym_count
;
79 /* Compute a hash code based using the same criteria as `strcmp_iw'. */
82 msymbol_hash_iw (const char *string
)
84 unsigned int hash
= 0;
85 while (*string
&& *string
!= '(')
87 while (isspace (*string
))
89 if (*string
&& *string
!= '(')
91 hash
= hash
* 67 + *string
- 113;
98 /* Compute a hash code for a string. */
101 msymbol_hash (const char *string
)
103 unsigned int hash
= 0;
104 for (; *string
; ++string
)
105 hash
= hash
* 67 + *string
- 113;
109 /* Add the minimal symbol SYM to an objfile's minsym hash table, TABLE. */
111 add_minsym_to_hash_table (struct minimal_symbol
*sym
,
112 struct minimal_symbol
**table
)
114 if (sym
->hash_next
== NULL
)
117 = msymbol_hash (SYMBOL_LINKAGE_NAME (sym
)) % MINIMAL_SYMBOL_HASH_SIZE
;
118 sym
->hash_next
= table
[hash
];
123 /* Add the minimal symbol SYM to an objfile's minsym demangled hash table,
126 add_minsym_to_demangled_hash_table (struct minimal_symbol
*sym
,
127 struct minimal_symbol
**table
)
129 if (sym
->demangled_hash_next
== NULL
)
131 unsigned int hash
= msymbol_hash_iw (SYMBOL_DEMANGLED_NAME (sym
)) % MINIMAL_SYMBOL_HASH_SIZE
;
132 sym
->demangled_hash_next
= table
[hash
];
138 /* Look through all the current minimal symbol tables and find the
139 first minimal symbol that matches NAME. If OBJF is non-NULL, limit
140 the search to that objfile. If SFILE is non-NULL, the only file-scope
141 symbols considered will be from that source file (global symbols are
142 still preferred). Returns a pointer to the minimal symbol that
143 matches, or NULL if no match is found.
145 Note: One instance where there may be duplicate minimal symbols with
146 the same name is when the symbol tables for a shared library and the
147 symbol tables for an executable contain global symbols with the same
148 names (the dynamic linker deals with the duplication). */
150 struct minimal_symbol
*
151 lookup_minimal_symbol (const char *name
, const char *sfile
,
152 struct objfile
*objf
)
154 struct objfile
*objfile
;
155 struct minimal_symbol
*msymbol
;
156 struct minimal_symbol
*found_symbol
= NULL
;
157 struct minimal_symbol
*found_file_symbol
= NULL
;
158 struct minimal_symbol
*trampoline_symbol
= NULL
;
160 unsigned int hash
= msymbol_hash (name
) % MINIMAL_SYMBOL_HASH_SIZE
;
161 unsigned int dem_hash
= msymbol_hash_iw (name
) % MINIMAL_SYMBOL_HASH_SIZE
;
163 #ifdef SOFUN_ADDRESS_MAYBE_MISSING
166 char *p
= strrchr (sfile
, '/');
172 for (objfile
= object_files
;
173 objfile
!= NULL
&& found_symbol
== NULL
;
174 objfile
= objfile
->next
)
176 if (objf
== NULL
|| objf
== objfile
)
178 /* Do two passes: the first over the ordinary hash table,
179 and the second over the demangled hash table. */
182 for (pass
= 1; pass
<= 2 && found_symbol
== NULL
; pass
++)
184 /* Select hash list according to pass. */
186 msymbol
= objfile
->msymbol_hash
[hash
];
188 msymbol
= objfile
->msymbol_demangled_hash
[dem_hash
];
190 while (msymbol
!= NULL
&& found_symbol
== NULL
)
192 /* FIXME: carlton/2003-02-27: This is an unholy
193 mixture of linkage names and natural names. If
194 you want to test the linkage names with strcmp,
195 do that. If you want to test the natural names
196 with strcmp_iw, use SYMBOL_MATCHES_NATURAL_NAME. */
197 if (strcmp (DEPRECATED_SYMBOL_NAME (msymbol
), (name
)) == 0
198 || (SYMBOL_DEMANGLED_NAME (msymbol
) != NULL
199 && strcmp_iw (SYMBOL_DEMANGLED_NAME (msymbol
),
202 switch (MSYMBOL_TYPE (msymbol
))
207 #ifdef SOFUN_ADDRESS_MAYBE_MISSING
208 if (sfile
== NULL
|| STREQ (msymbol
->filename
, sfile
))
209 found_file_symbol
= msymbol
;
211 /* We have neither the ability nor the need to
212 deal with the SFILE parameter. If we find
213 more than one symbol, just return the latest
214 one (the user can't expect useful behavior in
216 found_file_symbol
= msymbol
;
220 case mst_solib_trampoline
:
222 /* If a trampoline symbol is found, we prefer to
223 keep looking for the *real* symbol. If the
224 actual symbol is not found, then we'll use the
226 if (trampoline_symbol
== NULL
)
227 trampoline_symbol
= msymbol
;
232 found_symbol
= msymbol
;
237 /* Find the next symbol on the hash chain. */
239 msymbol
= msymbol
->hash_next
;
241 msymbol
= msymbol
->demangled_hash_next
;
246 /* External symbols are best. */
250 /* File-local symbols are next best. */
251 if (found_file_symbol
)
252 return found_file_symbol
;
254 /* Symbols for shared library trampolines are next best. */
255 if (trampoline_symbol
)
256 return trampoline_symbol
;
261 /* Look through all the current minimal symbol tables and find the
262 first minimal symbol that matches NAME and has text type. If OBJF
263 is non-NULL, limit the search to that objfile. If SFILE is non-NULL,
264 the only file-scope symbols considered will be from that source file
265 (global symbols are still preferred). Returns a pointer to the minimal
266 symbol that matches, or NULL if no match is found.
268 This function only searches the mangled (linkage) names. */
270 struct minimal_symbol
*
271 lookup_minimal_symbol_text (const char *name
, const char *sfile
,
272 struct objfile
*objf
)
274 struct objfile
*objfile
;
275 struct minimal_symbol
*msymbol
;
276 struct minimal_symbol
*found_symbol
= NULL
;
277 struct minimal_symbol
*found_file_symbol
= NULL
;
279 unsigned int hash
= msymbol_hash (name
) % MINIMAL_SYMBOL_HASH_SIZE
;
281 #ifdef SOFUN_ADDRESS_MAYBE_MISSING
284 char *p
= strrchr (sfile
, '/');
290 for (objfile
= object_files
;
291 objfile
!= NULL
&& found_symbol
== NULL
;
292 objfile
= objfile
->next
)
294 if (objf
== NULL
|| objf
== objfile
)
296 for (msymbol
= objfile
->msymbol_hash
[hash
];
297 msymbol
!= NULL
&& found_symbol
== NULL
;
298 msymbol
= msymbol
->hash_next
)
300 if (strcmp (SYMBOL_LINKAGE_NAME (msymbol
), name
) == 0 &&
301 (MSYMBOL_TYPE (msymbol
) == mst_text
||
302 MSYMBOL_TYPE (msymbol
) == mst_file_text
))
304 switch (MSYMBOL_TYPE (msymbol
))
307 #ifdef SOFUN_ADDRESS_MAYBE_MISSING
308 if (sfile
== NULL
|| STREQ (msymbol
->filename
, sfile
))
309 found_file_symbol
= msymbol
;
311 /* We have neither the ability nor the need to
312 deal with the SFILE parameter. If we find
313 more than one symbol, just return the latest
314 one (the user can't expect useful behavior in
316 found_file_symbol
= msymbol
;
320 found_symbol
= msymbol
;
327 /* External symbols are best. */
331 /* File-local symbols are next best. */
332 if (found_file_symbol
)
333 return found_file_symbol
;
338 /* Look through all the current minimal symbol tables and find the
339 first minimal symbol that matches NAME and is a solib trampoline. If OBJF
340 is non-NULL, limit the search to that objfile. If SFILE is non-NULL,
341 the only file-scope symbols considered will be from that source file
342 (global symbols are still preferred). Returns a pointer to the minimal
343 symbol that matches, or NULL if no match is found.
345 This function only searches the mangled (linkage) names. */
347 struct minimal_symbol
*
348 lookup_minimal_symbol_solib_trampoline (const char *name
,
350 struct objfile
*objf
)
352 struct objfile
*objfile
;
353 struct minimal_symbol
*msymbol
;
354 struct minimal_symbol
*found_symbol
= NULL
;
356 unsigned int hash
= msymbol_hash (name
) % MINIMAL_SYMBOL_HASH_SIZE
;
358 #ifdef SOFUN_ADDRESS_MAYBE_MISSING
361 char *p
= strrchr (sfile
, '/');
367 for (objfile
= object_files
;
368 objfile
!= NULL
&& found_symbol
== NULL
;
369 objfile
= objfile
->next
)
371 if (objf
== NULL
|| objf
== objfile
)
373 for (msymbol
= objfile
->msymbol_hash
[hash
];
374 msymbol
!= NULL
&& found_symbol
== NULL
;
375 msymbol
= msymbol
->hash_next
)
377 if (strcmp (SYMBOL_LINKAGE_NAME (msymbol
), name
) == 0 &&
378 MSYMBOL_TYPE (msymbol
) == mst_solib_trampoline
)
388 /* Search through the minimal symbol table for each objfile and find
389 the symbol whose address is the largest address that is still less
390 than or equal to PC, and matches SECTION (if non-null). Returns a
391 pointer to the minimal symbol if such a symbol is found, or NULL if
392 PC is not in a suitable range. Note that we need to look through
393 ALL the minimal symbol tables before deciding on the symbol that
394 comes closest to the specified PC. This is because objfiles can
395 overlap, for example objfile A has .text at 0x100 and .data at
396 0x40000 and objfile B has .text at 0x234 and .data at 0x40048. */
398 struct minimal_symbol
*
399 lookup_minimal_symbol_by_pc_section (CORE_ADDR pc
, asection
*section
)
404 struct objfile
*objfile
;
405 struct minimal_symbol
*msymbol
;
406 struct minimal_symbol
*best_symbol
= NULL
;
407 struct obj_section
*pc_section
;
409 /* pc has to be in a known section. This ensures that anything beyond
410 the end of the last segment doesn't appear to be part of the last
411 function in the last segment. */
412 pc_section
= find_pc_section (pc
);
413 if (pc_section
== NULL
)
416 /* If no section was specified, then just make sure that the PC is in
417 the same section as the minimal symbol we find. */
419 section
= pc_section
->the_bfd_section
;
421 /* FIXME drow/2003-07-19: Should we also check that PC is in SECTION
422 if we were passed a non-NULL SECTION argument? */
424 for (objfile
= object_files
;
426 objfile
= objfile
->next
)
428 /* If this objfile has a minimal symbol table, go search it using
429 a binary search. Note that a minimal symbol table always consists
430 of at least two symbols, a "real" symbol and the terminating
431 "null symbol". If there are no real symbols, then there is no
432 minimal symbol table at all. */
434 if (objfile
->minimal_symbol_count
> 0)
436 msymbol
= objfile
->msymbols
;
438 hi
= objfile
->minimal_symbol_count
- 1;
440 /* This code assumes that the minimal symbols are sorted by
441 ascending address values. If the pc value is greater than or
442 equal to the first symbol's address, then some symbol in this
443 minimal symbol table is a suitable candidate for being the
444 "best" symbol. This includes the last real symbol, for cases
445 where the pc value is larger than any address in this vector.
447 By iterating until the address associated with the current
448 hi index (the endpoint of the test interval) is less than
449 or equal to the desired pc value, we accomplish two things:
450 (1) the case where the pc value is larger than any minimal
451 symbol address is trivially solved, (2) the address associated
452 with the hi index is always the one we want when the interation
453 terminates. In essence, we are iterating the test interval
454 down until the pc value is pushed out of it from the high end.
456 Warning: this code is trickier than it would appear at first. */
458 /* Should also require that pc is <= end of objfile. FIXME! */
459 if (pc
>= SYMBOL_VALUE_ADDRESS (&msymbol
[lo
]))
461 while (SYMBOL_VALUE_ADDRESS (&msymbol
[hi
]) > pc
)
463 /* pc is still strictly less than highest address */
464 /* Note "new" will always be >= lo */
466 if ((SYMBOL_VALUE_ADDRESS (&msymbol
[new]) >= pc
) ||
477 /* If we have multiple symbols at the same address, we want
478 hi to point to the last one. That way we can find the
479 right symbol if it has an index greater than hi. */
480 while (hi
< objfile
->minimal_symbol_count
- 1
481 && (SYMBOL_VALUE_ADDRESS (&msymbol
[hi
])
482 == SYMBOL_VALUE_ADDRESS (&msymbol
[hi
+ 1])))
485 /* The minimal symbol indexed by hi now is the best one in this
486 objfile's minimal symbol table. See if it is the best one
489 /* Skip any absolute symbols. This is apparently what adb
490 and dbx do, and is needed for the CM-5. There are two
491 known possible problems: (1) on ELF, apparently end, edata,
492 etc. are absolute. Not sure ignoring them here is a big
493 deal, but if we want to use them, the fix would go in
494 elfread.c. (2) I think shared library entry points on the
495 NeXT are absolute. If we want special handling for this
496 it probably should be triggered by a special
497 mst_abs_or_lib or some such. */
499 && msymbol
[hi
].type
== mst_abs
)
502 /* If "section" specified, skip any symbol from wrong section */
503 /* This is the new code that distinguishes it from the old function */
506 /* Some types of debug info, such as COFF,
507 don't fill the bfd_section member, so don't
508 throw away symbols on those platforms. */
509 && SYMBOL_BFD_SECTION (&msymbol
[hi
]) != NULL
510 && SYMBOL_BFD_SECTION (&msymbol
[hi
]) != section
)
514 && ((best_symbol
== NULL
) ||
515 (SYMBOL_VALUE_ADDRESS (best_symbol
) <
516 SYMBOL_VALUE_ADDRESS (&msymbol
[hi
]))))
518 best_symbol
= &msymbol
[hi
];
523 return (best_symbol
);
526 /* Backward compatibility: search through the minimal symbol table
527 for a matching PC (no section given) */
529 struct minimal_symbol
*
530 lookup_minimal_symbol_by_pc (CORE_ADDR pc
)
532 return lookup_minimal_symbol_by_pc_section (pc
, find_pc_mapped_section (pc
));
536 /* Return leading symbol character for a BFD. If BFD is NULL,
537 return the leading symbol character from the main objfile. */
539 static int get_symbol_leading_char (bfd
*);
542 get_symbol_leading_char (bfd
*abfd
)
545 return bfd_get_symbol_leading_char (abfd
);
546 if (symfile_objfile
!= NULL
&& symfile_objfile
->obfd
!= NULL
)
547 return bfd_get_symbol_leading_char (symfile_objfile
->obfd
);
551 /* Prepare to start collecting minimal symbols. Note that presetting
552 msym_bunch_index to BUNCH_SIZE causes the first call to save a minimal
553 symbol to allocate the memory for the first bunch. */
556 init_minimal_symbol_collection (void)
560 msym_bunch_index
= BUNCH_SIZE
;
564 prim_record_minimal_symbol (const char *name
, CORE_ADDR address
,
565 enum minimal_symbol_type ms_type
,
566 struct objfile
*objfile
)
574 case mst_solib_trampoline
:
575 section
= SECT_OFF_TEXT (objfile
);
579 section
= SECT_OFF_DATA (objfile
);
583 section
= SECT_OFF_BSS (objfile
);
589 prim_record_minimal_symbol_and_info (name
, address
, ms_type
,
590 NULL
, section
, NULL
, objfile
);
593 /* Record a minimal symbol in the msym bunches. Returns the symbol
596 struct minimal_symbol
*
597 prim_record_minimal_symbol_and_info (const char *name
, CORE_ADDR address
,
598 enum minimal_symbol_type ms_type
,
599 char *info
, int section
,
600 asection
*bfd_section
,
601 struct objfile
*objfile
)
603 struct msym_bunch
*new;
604 struct minimal_symbol
*msymbol
;
606 if (ms_type
== mst_file_text
)
608 /* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into
609 the minimal symbols, because if there is also another symbol
610 at the same address (e.g. the first function of the file),
611 lookup_minimal_symbol_by_pc would have no way of getting the
614 && (strcmp (name
, GCC_COMPILED_FLAG_SYMBOL
) == 0
615 || strcmp (name
, GCC2_COMPILED_FLAG_SYMBOL
) == 0))
619 const char *tempstring
= name
;
620 if (tempstring
[0] == get_symbol_leading_char (objfile
->obfd
))
622 if (STREQN (tempstring
, "__gnu_compiled", 14))
627 if (msym_bunch_index
== BUNCH_SIZE
)
629 new = (struct msym_bunch
*) xmalloc (sizeof (struct msym_bunch
));
630 msym_bunch_index
= 0;
631 new->next
= msym_bunch
;
634 msymbol
= &msym_bunch
->contents
[msym_bunch_index
];
635 SYMBOL_INIT_LANGUAGE_SPECIFIC (msymbol
, language_unknown
);
636 SYMBOL_LANGUAGE (msymbol
) = language_auto
;
637 SYMBOL_SET_NAMES (msymbol
, (char *)name
, strlen (name
), objfile
);
639 SYMBOL_VALUE_ADDRESS (msymbol
) = address
;
640 SYMBOL_SECTION (msymbol
) = section
;
641 SYMBOL_BFD_SECTION (msymbol
) = bfd_section
;
643 MSYMBOL_TYPE (msymbol
) = ms_type
;
644 /* FIXME: This info, if it remains, needs its own field. */
645 MSYMBOL_INFO (msymbol
) = info
; /* FIXME! */
647 /* The hash pointers must be cleared! If they're not,
648 add_minsym_to_hash_table will NOT add this msymbol to the hash table. */
649 msymbol
->hash_next
= NULL
;
650 msymbol
->demangled_hash_next
= NULL
;
654 OBJSTAT (objfile
, n_minsyms
++);
658 /* Compare two minimal symbols by address and return a signed result based
659 on unsigned comparisons, so that we sort into unsigned numeric order.
660 Within groups with the same address, sort by name. */
663 compare_minimal_symbols (const void *fn1p
, const void *fn2p
)
665 const struct minimal_symbol
*fn1
;
666 const struct minimal_symbol
*fn2
;
668 fn1
= (const struct minimal_symbol
*) fn1p
;
669 fn2
= (const struct minimal_symbol
*) fn2p
;
671 if (SYMBOL_VALUE_ADDRESS (fn1
) < SYMBOL_VALUE_ADDRESS (fn2
))
673 return (-1); /* addr 1 is less than addr 2 */
675 else if (SYMBOL_VALUE_ADDRESS (fn1
) > SYMBOL_VALUE_ADDRESS (fn2
))
677 return (1); /* addr 1 is greater than addr 2 */
680 /* addrs are equal: sort by name */
682 char *name1
= SYMBOL_LINKAGE_NAME (fn1
);
683 char *name2
= SYMBOL_LINKAGE_NAME (fn2
);
685 if (name1
&& name2
) /* both have names */
686 return strcmp (name1
, name2
);
688 return 1; /* fn1 has no name, so it is "less" */
689 else if (name1
) /* fn2 has no name, so it is "less" */
692 return (0); /* neither has a name, so they're equal. */
696 /* Discard the currently collected minimal symbols, if any. If we wish
697 to save them for later use, we must have already copied them somewhere
698 else before calling this function.
700 FIXME: We could allocate the minimal symbol bunches on their own
701 obstack and then simply blow the obstack away when we are done with
702 it. Is it worth the extra trouble though? */
705 do_discard_minimal_symbols_cleanup (void *arg
)
707 struct msym_bunch
*next
;
709 while (msym_bunch
!= NULL
)
711 next
= msym_bunch
->next
;
718 make_cleanup_discard_minimal_symbols (void)
720 return make_cleanup (do_discard_minimal_symbols_cleanup
, 0);
725 /* Compact duplicate entries out of a minimal symbol table by walking
726 through the table and compacting out entries with duplicate addresses
727 and matching names. Return the number of entries remaining.
729 On entry, the table resides between msymbol[0] and msymbol[mcount].
730 On exit, it resides between msymbol[0] and msymbol[result_count].
732 When files contain multiple sources of symbol information, it is
733 possible for the minimal symbol table to contain many duplicate entries.
734 As an example, SVR4 systems use ELF formatted object files, which
735 usually contain at least two different types of symbol tables (a
736 standard ELF one and a smaller dynamic linking table), as well as
737 DWARF debugging information for files compiled with -g.
739 Without compacting, the minimal symbol table for gdb itself contains
740 over a 1000 duplicates, about a third of the total table size. Aside
741 from the potential trap of not noticing that two successive entries
742 identify the same location, this duplication impacts the time required
743 to linearly scan the table, which is done in a number of places. So we
744 just do one linear scan here and toss out the duplicates.
746 Note that we are not concerned here about recovering the space that
747 is potentially freed up, because the strings themselves are allocated
748 on the symbol_obstack, and will get automatically freed when the symbol
749 table is freed. The caller can free up the unused minimal symbols at
750 the end of the compacted region if their allocation strategy allows it.
752 Also note we only go up to the next to last entry within the loop
753 and then copy the last entry explicitly after the loop terminates.
755 Since the different sources of information for each symbol may
756 have different levels of "completeness", we may have duplicates
757 that have one entry with type "mst_unknown" and the other with a
758 known type. So if the one we are leaving alone has type mst_unknown,
759 overwrite its type with the type from the one we are compacting out. */
762 compact_minimal_symbols (struct minimal_symbol
*msymbol
, int mcount
,
763 struct objfile
*objfile
)
765 struct minimal_symbol
*copyfrom
;
766 struct minimal_symbol
*copyto
;
770 copyfrom
= copyto
= msymbol
;
771 while (copyfrom
< msymbol
+ mcount
- 1)
773 if (SYMBOL_VALUE_ADDRESS (copyfrom
) ==
774 SYMBOL_VALUE_ADDRESS ((copyfrom
+ 1)) &&
775 (STREQ (SYMBOL_LINKAGE_NAME (copyfrom
),
776 SYMBOL_LINKAGE_NAME ((copyfrom
+ 1)))))
778 if (MSYMBOL_TYPE ((copyfrom
+ 1)) == mst_unknown
)
780 MSYMBOL_TYPE ((copyfrom
+ 1)) = MSYMBOL_TYPE (copyfrom
);
785 *copyto
++ = *copyfrom
++;
787 *copyto
++ = *copyfrom
++;
788 mcount
= copyto
- msymbol
;
793 /* Build (or rebuild) the minimal symbol hash tables. This is necessary
794 after compacting or sorting the table since the entries move around
795 thus causing the internal minimal_symbol pointers to become jumbled. */
798 build_minimal_symbol_hash_tables (struct objfile
*objfile
)
801 struct minimal_symbol
*msym
;
803 /* Clear the hash tables. */
804 for (i
= 0; i
< MINIMAL_SYMBOL_HASH_SIZE
; i
++)
806 objfile
->msymbol_hash
[i
] = 0;
807 objfile
->msymbol_demangled_hash
[i
] = 0;
810 /* Now, (re)insert the actual entries. */
811 for (i
= objfile
->minimal_symbol_count
, msym
= objfile
->msymbols
;
816 add_minsym_to_hash_table (msym
, objfile
->msymbol_hash
);
818 msym
->demangled_hash_next
= 0;
819 if (SYMBOL_DEMANGLED_NAME (msym
) != NULL
)
820 add_minsym_to_demangled_hash_table (msym
,
821 objfile
->msymbol_demangled_hash
);
825 /* Add the minimal symbols in the existing bunches to the objfile's official
826 minimal symbol table. In most cases there is no minimal symbol table yet
827 for this objfile, and the existing bunches are used to create one. Once
828 in a while (for shared libraries for example), we add symbols (e.g. common
829 symbols) to an existing objfile.
831 Because of the way minimal symbols are collected, we generally have no way
832 of knowing what source language applies to any particular minimal symbol.
833 Specifically, we have no way of knowing if the minimal symbol comes from a
834 C++ compilation unit or not. So for the sake of supporting cached
835 demangled C++ names, we have no choice but to try and demangle each new one
836 that comes in. If the demangling succeeds, then we assume it is a C++
837 symbol and set the symbol's language and demangled name fields
838 appropriately. Note that in order to avoid unnecessary demanglings, and
839 allocating obstack space that subsequently can't be freed for the demangled
840 names, we mark all newly added symbols with language_auto. After
841 compaction of the minimal symbols, we go back and scan the entire minimal
842 symbol table looking for these new symbols. For each new symbol we attempt
843 to demangle it, and if successful, record it as a language_cplus symbol
844 and cache the demangled form on the symbol obstack. Symbols which don't
845 demangle are marked as language_unknown symbols, which inhibits future
846 attempts to demangle them if we later add more minimal symbols. */
849 install_minimal_symbols (struct objfile
*objfile
)
853 struct msym_bunch
*bunch
;
854 struct minimal_symbol
*msymbols
;
860 /* Allocate enough space in the obstack, into which we will gather the
861 bunches of new and existing minimal symbols, sort them, and then
862 compact out the duplicate entries. Once we have a final table,
863 we will give back the excess space. */
865 alloc_count
= msym_count
+ objfile
->minimal_symbol_count
+ 1;
866 obstack_blank (&objfile
->symbol_obstack
,
867 alloc_count
* sizeof (struct minimal_symbol
));
868 msymbols
= (struct minimal_symbol
*)
869 obstack_base (&objfile
->symbol_obstack
);
871 /* Copy in the existing minimal symbols, if there are any. */
873 if (objfile
->minimal_symbol_count
)
874 memcpy ((char *) msymbols
, (char *) objfile
->msymbols
,
875 objfile
->minimal_symbol_count
* sizeof (struct minimal_symbol
));
877 /* Walk through the list of minimal symbol bunches, adding each symbol
878 to the new contiguous array of symbols. Note that we start with the
879 current, possibly partially filled bunch (thus we use the current
880 msym_bunch_index for the first bunch we copy over), and thereafter
881 each bunch is full. */
883 mcount
= objfile
->minimal_symbol_count
;
884 leading_char
= get_symbol_leading_char (objfile
->obfd
);
886 for (bunch
= msym_bunch
; bunch
!= NULL
; bunch
= bunch
->next
)
888 for (bindex
= 0; bindex
< msym_bunch_index
; bindex
++, mcount
++)
890 msymbols
[mcount
] = bunch
->contents
[bindex
];
891 if (SYMBOL_LINKAGE_NAME (&msymbols
[mcount
])[0] == leading_char
)
893 SYMBOL_LINKAGE_NAME (&msymbols
[mcount
])++;
896 msym_bunch_index
= BUNCH_SIZE
;
899 /* Sort the minimal symbols by address. */
901 qsort (msymbols
, mcount
, sizeof (struct minimal_symbol
),
902 compare_minimal_symbols
);
904 /* Compact out any duplicates, and free up whatever space we are
907 mcount
= compact_minimal_symbols (msymbols
, mcount
, objfile
);
909 obstack_blank (&objfile
->symbol_obstack
,
910 (mcount
+ 1 - alloc_count
) * sizeof (struct minimal_symbol
));
911 msymbols
= (struct minimal_symbol
*)
912 obstack_finish (&objfile
->symbol_obstack
);
914 /* We also terminate the minimal symbol table with a "null symbol",
915 which is *not* included in the size of the table. This makes it
916 easier to find the end of the table when we are handed a pointer
917 to some symbol in the middle of it. Zero out the fields in the
918 "null symbol" allocated at the end of the array. Note that the
919 symbol count does *not* include this null symbol, which is why it
920 is indexed by mcount and not mcount-1. */
922 SYMBOL_LINKAGE_NAME (&msymbols
[mcount
]) = NULL
;
923 SYMBOL_VALUE_ADDRESS (&msymbols
[mcount
]) = 0;
924 MSYMBOL_INFO (&msymbols
[mcount
]) = NULL
;
925 MSYMBOL_TYPE (&msymbols
[mcount
]) = mst_unknown
;
926 SYMBOL_INIT_LANGUAGE_SPECIFIC (&msymbols
[mcount
], language_unknown
);
928 /* Attach the minimal symbol table to the specified objfile.
929 The strings themselves are also located in the symbol_obstack
932 objfile
->minimal_symbol_count
= mcount
;
933 objfile
->msymbols
= msymbols
;
935 /* Try to guess the appropriate C++ ABI by looking at the names
936 of the minimal symbols in the table. */
940 for (i
= 0; i
< mcount
; i
++)
942 /* If a symbol's name starts with _Z and was successfully
943 demangled, then we can assume we've found a GNU v3 symbol.
944 For now we set the C++ ABI globally; if the user is
945 mixing ABIs then the user will need to "set cp-abi"
947 const char *name
= SYMBOL_LINKAGE_NAME (&objfile
->msymbols
[i
]);
948 if (name
[0] == '_' && name
[1] == 'Z'
949 && SYMBOL_DEMANGLED_NAME (&objfile
->msymbols
[i
]) != NULL
)
951 set_cp_abi_as_auto_default ("gnu-v3");
957 /* Now build the hash tables; we can't do this incrementally
958 at an earlier point since we weren't finished with the obstack
959 yet. (And if the msymbol obstack gets moved, all the internal
960 pointers to other msymbols need to be adjusted.) */
961 build_minimal_symbol_hash_tables (objfile
);
965 /* Sort all the minimal symbols in OBJFILE. */
968 msymbols_sort (struct objfile
*objfile
)
970 qsort (objfile
->msymbols
, objfile
->minimal_symbol_count
,
971 sizeof (struct minimal_symbol
), compare_minimal_symbols
);
972 build_minimal_symbol_hash_tables (objfile
);
975 /* Check if PC is in a shared library trampoline code stub.
976 Return minimal symbol for the trampoline entry or NULL if PC is not
977 in a trampoline code stub. */
979 struct minimal_symbol
*
980 lookup_solib_trampoline_symbol_by_pc (CORE_ADDR pc
)
982 struct minimal_symbol
*msymbol
= lookup_minimal_symbol_by_pc (pc
);
984 if (msymbol
!= NULL
&& MSYMBOL_TYPE (msymbol
) == mst_solib_trampoline
)
989 /* If PC is in a shared library trampoline code stub, return the
990 address of the `real' function belonging to the stub.
991 Return 0 if PC is not in a trampoline code stub or if the real
992 function is not found in the minimal symbol table.
994 We may fail to find the right function if a function with the
995 same name is defined in more than one shared library, but this
996 is considered bad programming style. We could return 0 if we find
997 a duplicate function in case this matters someday. */
1000 find_solib_trampoline_target (CORE_ADDR pc
)
1002 struct objfile
*objfile
;
1003 struct minimal_symbol
*msymbol
;
1004 struct minimal_symbol
*tsymbol
= lookup_solib_trampoline_symbol_by_pc (pc
);
1006 if (tsymbol
!= NULL
)
1008 ALL_MSYMBOLS (objfile
, msymbol
)
1010 if (MSYMBOL_TYPE (msymbol
) == mst_text
1011 && STREQ (SYMBOL_LINKAGE_NAME (msymbol
),
1012 SYMBOL_LINKAGE_NAME (tsymbol
)))
1013 return SYMBOL_VALUE_ADDRESS (msymbol
);