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
,
349 struct objfile
*objf
)
351 struct objfile
*objfile
;
352 struct minimal_symbol
*msymbol
;
353 struct minimal_symbol
*found_symbol
= NULL
;
355 unsigned int hash
= msymbol_hash (name
) % MINIMAL_SYMBOL_HASH_SIZE
;
357 for (objfile
= object_files
;
358 objfile
!= NULL
&& found_symbol
== NULL
;
359 objfile
= objfile
->next
)
361 if (objf
== NULL
|| objf
== objfile
)
363 for (msymbol
= objfile
->msymbol_hash
[hash
];
364 msymbol
!= NULL
&& found_symbol
== NULL
;
365 msymbol
= msymbol
->hash_next
)
367 if (strcmp (SYMBOL_LINKAGE_NAME (msymbol
), name
) == 0 &&
368 MSYMBOL_TYPE (msymbol
) == mst_solib_trampoline
)
378 /* Search through the minimal symbol table for each objfile and find
379 the symbol whose address is the largest address that is still less
380 than or equal to PC, and matches SECTION (if non-null). Returns a
381 pointer to the minimal symbol if such a symbol is found, or NULL if
382 PC is not in a suitable range. Note that we need to look through
383 ALL the minimal symbol tables before deciding on the symbol that
384 comes closest to the specified PC. This is because objfiles can
385 overlap, for example objfile A has .text at 0x100 and .data at
386 0x40000 and objfile B has .text at 0x234 and .data at 0x40048. */
388 struct minimal_symbol
*
389 lookup_minimal_symbol_by_pc_section (CORE_ADDR pc
, asection
*section
)
394 struct objfile
*objfile
;
395 struct minimal_symbol
*msymbol
;
396 struct minimal_symbol
*best_symbol
= NULL
;
397 struct obj_section
*pc_section
;
399 /* pc has to be in a known section. This ensures that anything beyond
400 the end of the last segment doesn't appear to be part of the last
401 function in the last segment. */
402 pc_section
= find_pc_section (pc
);
403 if (pc_section
== NULL
)
406 /* If no section was specified, then just make sure that the PC is in
407 the same section as the minimal symbol we find. */
409 section
= pc_section
->the_bfd_section
;
411 /* FIXME drow/2003-07-19: Should we also check that PC is in SECTION
412 if we were passed a non-NULL SECTION argument? */
414 for (objfile
= object_files
;
416 objfile
= objfile
->next
)
418 /* If this objfile has a minimal symbol table, go search it using
419 a binary search. Note that a minimal symbol table always consists
420 of at least two symbols, a "real" symbol and the terminating
421 "null symbol". If there are no real symbols, then there is no
422 minimal symbol table at all. */
424 if (objfile
->minimal_symbol_count
> 0)
426 msymbol
= objfile
->msymbols
;
428 hi
= objfile
->minimal_symbol_count
- 1;
430 /* This code assumes that the minimal symbols are sorted by
431 ascending address values. If the pc value is greater than or
432 equal to the first symbol's address, then some symbol in this
433 minimal symbol table is a suitable candidate for being the
434 "best" symbol. This includes the last real symbol, for cases
435 where the pc value is larger than any address in this vector.
437 By iterating until the address associated with the current
438 hi index (the endpoint of the test interval) is less than
439 or equal to the desired pc value, we accomplish two things:
440 (1) the case where the pc value is larger than any minimal
441 symbol address is trivially solved, (2) the address associated
442 with the hi index is always the one we want when the interation
443 terminates. In essence, we are iterating the test interval
444 down until the pc value is pushed out of it from the high end.
446 Warning: this code is trickier than it would appear at first. */
448 /* Should also require that pc is <= end of objfile. FIXME! */
449 if (pc
>= SYMBOL_VALUE_ADDRESS (&msymbol
[lo
]))
451 while (SYMBOL_VALUE_ADDRESS (&msymbol
[hi
]) > pc
)
453 /* pc is still strictly less than highest address */
454 /* Note "new" will always be >= lo */
456 if ((SYMBOL_VALUE_ADDRESS (&msymbol
[new]) >= pc
) ||
467 /* If we have multiple symbols at the same address, we want
468 hi to point to the last one. That way we can find the
469 right symbol if it has an index greater than hi. */
470 while (hi
< objfile
->minimal_symbol_count
- 1
471 && (SYMBOL_VALUE_ADDRESS (&msymbol
[hi
])
472 == SYMBOL_VALUE_ADDRESS (&msymbol
[hi
+ 1])))
475 /* The minimal symbol indexed by hi now is the best one in this
476 objfile's minimal symbol table. See if it is the best one
479 /* Skip any absolute symbols. This is apparently what adb
480 and dbx do, and is needed for the CM-5. There are two
481 known possible problems: (1) on ELF, apparently end, edata,
482 etc. are absolute. Not sure ignoring them here is a big
483 deal, but if we want to use them, the fix would go in
484 elfread.c. (2) I think shared library entry points on the
485 NeXT are absolute. If we want special handling for this
486 it probably should be triggered by a special
487 mst_abs_or_lib or some such. */
489 && msymbol
[hi
].type
== mst_abs
)
492 /* If "section" specified, skip any symbol from wrong section */
493 /* This is the new code that distinguishes it from the old function */
496 /* Some types of debug info, such as COFF,
497 don't fill the bfd_section member, so don't
498 throw away symbols on those platforms. */
499 && SYMBOL_BFD_SECTION (&msymbol
[hi
]) != NULL
500 && SYMBOL_BFD_SECTION (&msymbol
[hi
]) != section
)
504 && ((best_symbol
== NULL
) ||
505 (SYMBOL_VALUE_ADDRESS (best_symbol
) <
506 SYMBOL_VALUE_ADDRESS (&msymbol
[hi
]))))
508 best_symbol
= &msymbol
[hi
];
513 return (best_symbol
);
516 /* Backward compatibility: search through the minimal symbol table
517 for a matching PC (no section given) */
519 struct minimal_symbol
*
520 lookup_minimal_symbol_by_pc (CORE_ADDR pc
)
522 return lookup_minimal_symbol_by_pc_section (pc
, find_pc_mapped_section (pc
));
526 /* Return leading symbol character for a BFD. If BFD is NULL,
527 return the leading symbol character from the main objfile. */
529 static int get_symbol_leading_char (bfd
*);
532 get_symbol_leading_char (bfd
*abfd
)
535 return bfd_get_symbol_leading_char (abfd
);
536 if (symfile_objfile
!= NULL
&& symfile_objfile
->obfd
!= NULL
)
537 return bfd_get_symbol_leading_char (symfile_objfile
->obfd
);
541 /* Prepare to start collecting minimal symbols. Note that presetting
542 msym_bunch_index to BUNCH_SIZE causes the first call to save a minimal
543 symbol to allocate the memory for the first bunch. */
546 init_minimal_symbol_collection (void)
550 msym_bunch_index
= BUNCH_SIZE
;
554 prim_record_minimal_symbol (const char *name
, CORE_ADDR address
,
555 enum minimal_symbol_type ms_type
,
556 struct objfile
*objfile
)
564 case mst_solib_trampoline
:
565 section
= SECT_OFF_TEXT (objfile
);
569 section
= SECT_OFF_DATA (objfile
);
573 section
= SECT_OFF_BSS (objfile
);
579 prim_record_minimal_symbol_and_info (name
, address
, ms_type
,
580 NULL
, section
, NULL
, objfile
);
583 /* Record a minimal symbol in the msym bunches. Returns the symbol
586 struct minimal_symbol
*
587 prim_record_minimal_symbol_and_info (const char *name
, CORE_ADDR address
,
588 enum minimal_symbol_type ms_type
,
589 char *info
, int section
,
590 asection
*bfd_section
,
591 struct objfile
*objfile
)
593 struct msym_bunch
*new;
594 struct minimal_symbol
*msymbol
;
596 if (ms_type
== mst_file_text
)
598 /* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into
599 the minimal symbols, because if there is also another symbol
600 at the same address (e.g. the first function of the file),
601 lookup_minimal_symbol_by_pc would have no way of getting the
604 && (strcmp (name
, GCC_COMPILED_FLAG_SYMBOL
) == 0
605 || strcmp (name
, GCC2_COMPILED_FLAG_SYMBOL
) == 0))
609 const char *tempstring
= name
;
610 if (tempstring
[0] == get_symbol_leading_char (objfile
->obfd
))
612 if (STREQN (tempstring
, "__gnu_compiled", 14))
617 if (msym_bunch_index
== BUNCH_SIZE
)
619 new = (struct msym_bunch
*) xmalloc (sizeof (struct msym_bunch
));
620 msym_bunch_index
= 0;
621 new->next
= msym_bunch
;
624 msymbol
= &msym_bunch
->contents
[msym_bunch_index
];
625 SYMBOL_INIT_LANGUAGE_SPECIFIC (msymbol
, language_unknown
);
626 SYMBOL_LANGUAGE (msymbol
) = language_auto
;
627 SYMBOL_SET_NAMES (msymbol
, (char *)name
, strlen (name
), objfile
);
629 SYMBOL_VALUE_ADDRESS (msymbol
) = address
;
630 SYMBOL_SECTION (msymbol
) = section
;
631 SYMBOL_BFD_SECTION (msymbol
) = bfd_section
;
633 MSYMBOL_TYPE (msymbol
) = ms_type
;
634 /* FIXME: This info, if it remains, needs its own field. */
635 MSYMBOL_INFO (msymbol
) = info
; /* FIXME! */
637 /* The hash pointers must be cleared! If they're not,
638 add_minsym_to_hash_table will NOT add this msymbol to the hash table. */
639 msymbol
->hash_next
= NULL
;
640 msymbol
->demangled_hash_next
= NULL
;
644 OBJSTAT (objfile
, n_minsyms
++);
648 /* Compare two minimal symbols by address and return a signed result based
649 on unsigned comparisons, so that we sort into unsigned numeric order.
650 Within groups with the same address, sort by name. */
653 compare_minimal_symbols (const void *fn1p
, const void *fn2p
)
655 const struct minimal_symbol
*fn1
;
656 const struct minimal_symbol
*fn2
;
658 fn1
= (const struct minimal_symbol
*) fn1p
;
659 fn2
= (const struct minimal_symbol
*) fn2p
;
661 if (SYMBOL_VALUE_ADDRESS (fn1
) < SYMBOL_VALUE_ADDRESS (fn2
))
663 return (-1); /* addr 1 is less than addr 2 */
665 else if (SYMBOL_VALUE_ADDRESS (fn1
) > SYMBOL_VALUE_ADDRESS (fn2
))
667 return (1); /* addr 1 is greater than addr 2 */
670 /* addrs are equal: sort by name */
672 char *name1
= SYMBOL_LINKAGE_NAME (fn1
);
673 char *name2
= SYMBOL_LINKAGE_NAME (fn2
);
675 if (name1
&& name2
) /* both have names */
676 return strcmp (name1
, name2
);
678 return 1; /* fn1 has no name, so it is "less" */
679 else if (name1
) /* fn2 has no name, so it is "less" */
682 return (0); /* neither has a name, so they're equal. */
686 /* Discard the currently collected minimal symbols, if any. If we wish
687 to save them for later use, we must have already copied them somewhere
688 else before calling this function.
690 FIXME: We could allocate the minimal symbol bunches on their own
691 obstack and then simply blow the obstack away when we are done with
692 it. Is it worth the extra trouble though? */
695 do_discard_minimal_symbols_cleanup (void *arg
)
697 struct msym_bunch
*next
;
699 while (msym_bunch
!= NULL
)
701 next
= msym_bunch
->next
;
708 make_cleanup_discard_minimal_symbols (void)
710 return make_cleanup (do_discard_minimal_symbols_cleanup
, 0);
715 /* Compact duplicate entries out of a minimal symbol table by walking
716 through the table and compacting out entries with duplicate addresses
717 and matching names. Return the number of entries remaining.
719 On entry, the table resides between msymbol[0] and msymbol[mcount].
720 On exit, it resides between msymbol[0] and msymbol[result_count].
722 When files contain multiple sources of symbol information, it is
723 possible for the minimal symbol table to contain many duplicate entries.
724 As an example, SVR4 systems use ELF formatted object files, which
725 usually contain at least two different types of symbol tables (a
726 standard ELF one and a smaller dynamic linking table), as well as
727 DWARF debugging information for files compiled with -g.
729 Without compacting, the minimal symbol table for gdb itself contains
730 over a 1000 duplicates, about a third of the total table size. Aside
731 from the potential trap of not noticing that two successive entries
732 identify the same location, this duplication impacts the time required
733 to linearly scan the table, which is done in a number of places. So we
734 just do one linear scan here and toss out the duplicates.
736 Note that we are not concerned here about recovering the space that
737 is potentially freed up, because the strings themselves are allocated
738 on the symbol_obstack, and will get automatically freed when the symbol
739 table is freed. The caller can free up the unused minimal symbols at
740 the end of the compacted region if their allocation strategy allows it.
742 Also note we only go up to the next to last entry within the loop
743 and then copy the last entry explicitly after the loop terminates.
745 Since the different sources of information for each symbol may
746 have different levels of "completeness", we may have duplicates
747 that have one entry with type "mst_unknown" and the other with a
748 known type. So if the one we are leaving alone has type mst_unknown,
749 overwrite its type with the type from the one we are compacting out. */
752 compact_minimal_symbols (struct minimal_symbol
*msymbol
, int mcount
,
753 struct objfile
*objfile
)
755 struct minimal_symbol
*copyfrom
;
756 struct minimal_symbol
*copyto
;
760 copyfrom
= copyto
= msymbol
;
761 while (copyfrom
< msymbol
+ mcount
- 1)
763 if (SYMBOL_VALUE_ADDRESS (copyfrom
) ==
764 SYMBOL_VALUE_ADDRESS ((copyfrom
+ 1)) &&
765 (STREQ (SYMBOL_LINKAGE_NAME (copyfrom
),
766 SYMBOL_LINKAGE_NAME ((copyfrom
+ 1)))))
768 if (MSYMBOL_TYPE ((copyfrom
+ 1)) == mst_unknown
)
770 MSYMBOL_TYPE ((copyfrom
+ 1)) = MSYMBOL_TYPE (copyfrom
);
775 *copyto
++ = *copyfrom
++;
777 *copyto
++ = *copyfrom
++;
778 mcount
= copyto
- msymbol
;
783 /* Build (or rebuild) the minimal symbol hash tables. This is necessary
784 after compacting or sorting the table since the entries move around
785 thus causing the internal minimal_symbol pointers to become jumbled. */
788 build_minimal_symbol_hash_tables (struct objfile
*objfile
)
791 struct minimal_symbol
*msym
;
793 /* Clear the hash tables. */
794 for (i
= 0; i
< MINIMAL_SYMBOL_HASH_SIZE
; i
++)
796 objfile
->msymbol_hash
[i
] = 0;
797 objfile
->msymbol_demangled_hash
[i
] = 0;
800 /* Now, (re)insert the actual entries. */
801 for (i
= objfile
->minimal_symbol_count
, msym
= objfile
->msymbols
;
806 add_minsym_to_hash_table (msym
, objfile
->msymbol_hash
);
808 msym
->demangled_hash_next
= 0;
809 if (SYMBOL_DEMANGLED_NAME (msym
) != NULL
)
810 add_minsym_to_demangled_hash_table (msym
,
811 objfile
->msymbol_demangled_hash
);
815 /* Add the minimal symbols in the existing bunches to the objfile's official
816 minimal symbol table. In most cases there is no minimal symbol table yet
817 for this objfile, and the existing bunches are used to create one. Once
818 in a while (for shared libraries for example), we add symbols (e.g. common
819 symbols) to an existing objfile.
821 Because of the way minimal symbols are collected, we generally have no way
822 of knowing what source language applies to any particular minimal symbol.
823 Specifically, we have no way of knowing if the minimal symbol comes from a
824 C++ compilation unit or not. So for the sake of supporting cached
825 demangled C++ names, we have no choice but to try and demangle each new one
826 that comes in. If the demangling succeeds, then we assume it is a C++
827 symbol and set the symbol's language and demangled name fields
828 appropriately. Note that in order to avoid unnecessary demanglings, and
829 allocating obstack space that subsequently can't be freed for the demangled
830 names, we mark all newly added symbols with language_auto. After
831 compaction of the minimal symbols, we go back and scan the entire minimal
832 symbol table looking for these new symbols. For each new symbol we attempt
833 to demangle it, and if successful, record it as a language_cplus symbol
834 and cache the demangled form on the symbol obstack. Symbols which don't
835 demangle are marked as language_unknown symbols, which inhibits future
836 attempts to demangle them if we later add more minimal symbols. */
839 install_minimal_symbols (struct objfile
*objfile
)
843 struct msym_bunch
*bunch
;
844 struct minimal_symbol
*msymbols
;
850 /* Allocate enough space in the obstack, into which we will gather the
851 bunches of new and existing minimal symbols, sort them, and then
852 compact out the duplicate entries. Once we have a final table,
853 we will give back the excess space. */
855 alloc_count
= msym_count
+ objfile
->minimal_symbol_count
+ 1;
856 obstack_blank (&objfile
->symbol_obstack
,
857 alloc_count
* sizeof (struct minimal_symbol
));
858 msymbols
= (struct minimal_symbol
*)
859 obstack_base (&objfile
->symbol_obstack
);
861 /* Copy in the existing minimal symbols, if there are any. */
863 if (objfile
->minimal_symbol_count
)
864 memcpy ((char *) msymbols
, (char *) objfile
->msymbols
,
865 objfile
->minimal_symbol_count
* sizeof (struct minimal_symbol
));
867 /* Walk through the list of minimal symbol bunches, adding each symbol
868 to the new contiguous array of symbols. Note that we start with the
869 current, possibly partially filled bunch (thus we use the current
870 msym_bunch_index for the first bunch we copy over), and thereafter
871 each bunch is full. */
873 mcount
= objfile
->minimal_symbol_count
;
874 leading_char
= get_symbol_leading_char (objfile
->obfd
);
876 for (bunch
= msym_bunch
; bunch
!= NULL
; bunch
= bunch
->next
)
878 for (bindex
= 0; bindex
< msym_bunch_index
; bindex
++, mcount
++)
880 msymbols
[mcount
] = bunch
->contents
[bindex
];
881 if (SYMBOL_LINKAGE_NAME (&msymbols
[mcount
])[0] == leading_char
)
883 SYMBOL_LINKAGE_NAME (&msymbols
[mcount
])++;
886 msym_bunch_index
= BUNCH_SIZE
;
889 /* Sort the minimal symbols by address. */
891 qsort (msymbols
, mcount
, sizeof (struct minimal_symbol
),
892 compare_minimal_symbols
);
894 /* Compact out any duplicates, and free up whatever space we are
897 mcount
= compact_minimal_symbols (msymbols
, mcount
, objfile
);
899 obstack_blank (&objfile
->symbol_obstack
,
900 (mcount
+ 1 - alloc_count
) * sizeof (struct minimal_symbol
));
901 msymbols
= (struct minimal_symbol
*)
902 obstack_finish (&objfile
->symbol_obstack
);
904 /* We also terminate the minimal symbol table with a "null symbol",
905 which is *not* included in the size of the table. This makes it
906 easier to find the end of the table when we are handed a pointer
907 to some symbol in the middle of it. Zero out the fields in the
908 "null symbol" allocated at the end of the array. Note that the
909 symbol count does *not* include this null symbol, which is why it
910 is indexed by mcount and not mcount-1. */
912 SYMBOL_LINKAGE_NAME (&msymbols
[mcount
]) = NULL
;
913 SYMBOL_VALUE_ADDRESS (&msymbols
[mcount
]) = 0;
914 MSYMBOL_INFO (&msymbols
[mcount
]) = NULL
;
915 MSYMBOL_TYPE (&msymbols
[mcount
]) = mst_unknown
;
916 SYMBOL_INIT_LANGUAGE_SPECIFIC (&msymbols
[mcount
], language_unknown
);
918 /* Attach the minimal symbol table to the specified objfile.
919 The strings themselves are also located in the symbol_obstack
922 objfile
->minimal_symbol_count
= mcount
;
923 objfile
->msymbols
= msymbols
;
925 /* Try to guess the appropriate C++ ABI by looking at the names
926 of the minimal symbols in the table. */
930 for (i
= 0; i
< mcount
; i
++)
932 /* If a symbol's name starts with _Z and was successfully
933 demangled, then we can assume we've found a GNU v3 symbol.
934 For now we set the C++ ABI globally; if the user is
935 mixing ABIs then the user will need to "set cp-abi"
937 const char *name
= SYMBOL_LINKAGE_NAME (&objfile
->msymbols
[i
]);
938 if (name
[0] == '_' && name
[1] == 'Z'
939 && SYMBOL_DEMANGLED_NAME (&objfile
->msymbols
[i
]) != NULL
)
941 set_cp_abi_as_auto_default ("gnu-v3");
947 /* Now build the hash tables; we can't do this incrementally
948 at an earlier point since we weren't finished with the obstack
949 yet. (And if the msymbol obstack gets moved, all the internal
950 pointers to other msymbols need to be adjusted.) */
951 build_minimal_symbol_hash_tables (objfile
);
955 /* Sort all the minimal symbols in OBJFILE. */
958 msymbols_sort (struct objfile
*objfile
)
960 qsort (objfile
->msymbols
, objfile
->minimal_symbol_count
,
961 sizeof (struct minimal_symbol
), compare_minimal_symbols
);
962 build_minimal_symbol_hash_tables (objfile
);
965 /* Check if PC is in a shared library trampoline code stub.
966 Return minimal symbol for the trampoline entry or NULL if PC is not
967 in a trampoline code stub. */
969 struct minimal_symbol
*
970 lookup_solib_trampoline_symbol_by_pc (CORE_ADDR pc
)
972 struct minimal_symbol
*msymbol
= lookup_minimal_symbol_by_pc (pc
);
974 if (msymbol
!= NULL
&& MSYMBOL_TYPE (msymbol
) == mst_solib_trampoline
)
979 /* If PC is in a shared library trampoline code stub, return the
980 address of the `real' function belonging to the stub.
981 Return 0 if PC is not in a trampoline code stub or if the real
982 function is not found in the minimal symbol table.
984 We may fail to find the right function if a function with the
985 same name is defined in more than one shared library, but this
986 is considered bad programming style. We could return 0 if we find
987 a duplicate function in case this matters someday. */
990 find_solib_trampoline_target (CORE_ADDR pc
)
992 struct objfile
*objfile
;
993 struct minimal_symbol
*msymbol
;
994 struct minimal_symbol
*tsymbol
= lookup_solib_trampoline_symbol_by_pc (pc
);
998 ALL_MSYMBOLS (objfile
, msymbol
)
1000 if (MSYMBOL_TYPE (msymbol
) == mst_text
1001 && STREQ (SYMBOL_LINKAGE_NAME (msymbol
),
1002 SYMBOL_LINKAGE_NAME (tsymbol
)))
1003 return SYMBOL_VALUE_ADDRESS (msymbol
);