1 /* Block-related functions for the GNU debugger, GDB.
3 Copyright (C) 2003-2014 Free Software Foundation, Inc.
5 This file is part of GDB.
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 3 of the License, or
10 (at your option) any later version.
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.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "gdb_obstack.h"
25 #include "cp-support.h"
29 /* This is used by struct block to store namespace-related info for
30 C++ files, namely using declarations and the current namespace in
33 struct block_namespace_info
36 struct using_direct
*using;
39 static void block_initialize_namespace (struct block
*block
,
40 struct obstack
*obstack
);
42 /* Return Nonzero if block a is lexically nested within block b,
43 or if a and b have the same pc range.
44 Return zero otherwise. */
47 contained_in (const struct block
*a
, const struct block
*b
)
56 /* If A is a function block, then A cannot be contained in B,
57 except if A was inlined. */
58 if (BLOCK_FUNCTION (a
) != NULL
&& !block_inlined_p (a
))
60 a
= BLOCK_SUPERBLOCK (a
);
68 /* Return the symbol for the function which contains a specified
69 lexical block, described by a struct block BL. The return value
70 will not be an inlined function; the containing function will be
74 block_linkage_function (const struct block
*bl
)
76 while ((BLOCK_FUNCTION (bl
) == NULL
|| block_inlined_p (bl
))
77 && BLOCK_SUPERBLOCK (bl
) != NULL
)
78 bl
= BLOCK_SUPERBLOCK (bl
);
80 return BLOCK_FUNCTION (bl
);
83 /* Return the symbol for the function which contains a specified
84 block, described by a struct block BL. The return value will be
85 the closest enclosing function, which might be an inline
89 block_containing_function (const struct block
*bl
)
91 while (BLOCK_FUNCTION (bl
) == NULL
&& BLOCK_SUPERBLOCK (bl
) != NULL
)
92 bl
= BLOCK_SUPERBLOCK (bl
);
94 return BLOCK_FUNCTION (bl
);
97 /* Return one if BL represents an inlined function. */
100 block_inlined_p (const struct block
*bl
)
102 return BLOCK_FUNCTION (bl
) != NULL
&& SYMBOL_INLINED (BLOCK_FUNCTION (bl
));
105 /* A helper function that checks whether PC is in the blockvector BL.
106 It returns the containing block if there is one, or else NULL. */
108 static struct block
*
109 find_block_in_blockvector (const struct blockvector
*bl
, CORE_ADDR pc
)
114 /* If we have an addrmap mapping code addresses to blocks, then use
116 if (BLOCKVECTOR_MAP (bl
))
117 return addrmap_find (BLOCKVECTOR_MAP (bl
), pc
);
119 /* Otherwise, use binary search to find the last block that starts
121 Note: GLOBAL_BLOCK is block 0, STATIC_BLOCK is block 1.
122 They both have the same START,END values.
123 Historically this code would choose STATIC_BLOCK over GLOBAL_BLOCK but the
124 fact that this choice was made was subtle, now we make it explicit. */
125 gdb_assert (BLOCKVECTOR_NBLOCKS (bl
) >= 2);
127 top
= BLOCKVECTOR_NBLOCKS (bl
);
129 while (top
- bot
> 1)
131 half
= (top
- bot
+ 1) >> 1;
132 b
= BLOCKVECTOR_BLOCK (bl
, bot
+ half
);
133 if (BLOCK_START (b
) <= pc
)
139 /* Now search backward for a block that ends after PC. */
141 while (bot
>= STATIC_BLOCK
)
143 b
= BLOCKVECTOR_BLOCK (bl
, bot
);
144 if (BLOCK_END (b
) > pc
)
152 /* Return the blockvector immediately containing the innermost lexical
153 block containing the specified pc value and section, or 0 if there
154 is none. PBLOCK is a pointer to the block. If PBLOCK is NULL, we
155 don't pass this information back to the caller. */
157 const struct blockvector
*
158 blockvector_for_pc_sect (CORE_ADDR pc
, struct obj_section
*section
,
159 const struct block
**pblock
, struct symtab
*symtab
)
161 const struct blockvector
*bl
;
164 if (symtab
== 0) /* if no symtab specified by caller */
166 /* First search all symtabs for one whose file contains our pc */
167 symtab
= find_pc_sect_symtab (pc
, section
);
172 bl
= SYMTAB_BLOCKVECTOR (symtab
);
174 /* Then search that symtab for the smallest block that wins. */
175 b
= find_block_in_blockvector (bl
, pc
);
184 /* Return true if the blockvector BV contains PC, false otherwise. */
187 blockvector_contains_pc (const struct blockvector
*bv
, CORE_ADDR pc
)
189 return find_block_in_blockvector (bv
, pc
) != NULL
;
192 /* Return call_site for specified PC in GDBARCH. PC must match exactly, it
193 must be the next instruction after call (or after tail call jump). Throw
194 NO_ENTRY_VALUE_ERROR otherwise. This function never returns NULL. */
197 call_site_for_pc (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
199 struct symtab
*symtab
;
202 /* -1 as tail call PC can be already after the compilation unit range. */
203 symtab
= find_pc_symtab (pc
- 1);
205 if (symtab
!= NULL
&& symtab
->call_site_htab
!= NULL
)
206 slot
= htab_find_slot (symtab
->call_site_htab
, &pc
, NO_INSERT
);
210 struct bound_minimal_symbol msym
= lookup_minimal_symbol_by_pc (pc
);
212 /* DW_TAG_gnu_call_site will be missing just if GCC could not determine
214 throw_error (NO_ENTRY_VALUE_ERROR
,
215 _("DW_OP_GNU_entry_value resolving cannot find "
216 "DW_TAG_GNU_call_site %s in %s"),
217 paddress (gdbarch
, pc
),
218 (msym
.minsym
== NULL
? "???"
219 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
225 /* Return the blockvector immediately containing the innermost lexical block
226 containing the specified pc value, or 0 if there is none.
227 Backward compatibility, no section. */
229 const struct blockvector
*
230 blockvector_for_pc (CORE_ADDR pc
, const struct block
**pblock
)
232 return blockvector_for_pc_sect (pc
, find_pc_mapped_section (pc
),
236 /* Return the innermost lexical block containing the specified pc value
237 in the specified section, or 0 if there is none. */
240 block_for_pc_sect (CORE_ADDR pc
, struct obj_section
*section
)
242 const struct blockvector
*bl
;
243 const struct block
*b
;
245 bl
= blockvector_for_pc_sect (pc
, section
, &b
, NULL
);
251 /* Return the innermost lexical block containing the specified pc value,
252 or 0 if there is none. Backward compatibility, no section. */
255 block_for_pc (CORE_ADDR pc
)
257 return block_for_pc_sect (pc
, find_pc_mapped_section (pc
));
260 /* Now come some functions designed to deal with C++ namespace issues.
261 The accessors are safe to use even in the non-C++ case. */
263 /* This returns the namespace that BLOCK is enclosed in, or "" if it
264 isn't enclosed in a namespace at all. This travels the chain of
265 superblocks looking for a scope, if necessary. */
268 block_scope (const struct block
*block
)
270 for (; block
!= NULL
; block
= BLOCK_SUPERBLOCK (block
))
272 if (BLOCK_NAMESPACE (block
) != NULL
273 && BLOCK_NAMESPACE (block
)->scope
!= NULL
)
274 return BLOCK_NAMESPACE (block
)->scope
;
280 /* Set BLOCK's scope member to SCOPE; if needed, allocate memory via
281 OBSTACK. (It won't make a copy of SCOPE, however, so that already
282 has to be allocated correctly.) */
285 block_set_scope (struct block
*block
, const char *scope
,
286 struct obstack
*obstack
)
288 block_initialize_namespace (block
, obstack
);
290 BLOCK_NAMESPACE (block
)->scope
= scope
;
293 /* This returns the using directives list associated with BLOCK, if
296 struct using_direct
*
297 block_using (const struct block
*block
)
299 if (block
== NULL
|| BLOCK_NAMESPACE (block
) == NULL
)
302 return BLOCK_NAMESPACE (block
)->using;
305 /* Set BLOCK's using member to USING; if needed, allocate memory via
306 OBSTACK. (It won't make a copy of USING, however, so that already
307 has to be allocated correctly.) */
310 block_set_using (struct block
*block
,
311 struct using_direct
*using,
312 struct obstack
*obstack
)
314 block_initialize_namespace (block
, obstack
);
316 BLOCK_NAMESPACE (block
)->using = using;
319 /* If BLOCK_NAMESPACE (block) is NULL, allocate it via OBSTACK and
320 ititialize its members to zero. */
323 block_initialize_namespace (struct block
*block
, struct obstack
*obstack
)
325 if (BLOCK_NAMESPACE (block
) == NULL
)
327 BLOCK_NAMESPACE (block
)
328 = obstack_alloc (obstack
, sizeof (struct block_namespace_info
));
329 BLOCK_NAMESPACE (block
)->scope
= NULL
;
330 BLOCK_NAMESPACE (block
)->using = NULL
;
334 /* Return the static block associated to BLOCK. Return NULL if block
335 is NULL or if block is a global block. */
338 block_static_block (const struct block
*block
)
340 if (block
== NULL
|| BLOCK_SUPERBLOCK (block
) == NULL
)
343 while (BLOCK_SUPERBLOCK (BLOCK_SUPERBLOCK (block
)) != NULL
)
344 block
= BLOCK_SUPERBLOCK (block
);
349 /* Return the static block associated to BLOCK. Return NULL if block
353 block_global_block (const struct block
*block
)
358 while (BLOCK_SUPERBLOCK (block
) != NULL
)
359 block
= BLOCK_SUPERBLOCK (block
);
364 /* Allocate a block on OBSTACK, and initialize its elements to
365 zero/NULL. This is useful for creating "dummy" blocks that don't
366 correspond to actual source files.
368 Warning: it sets the block's BLOCK_DICT to NULL, which isn't a
369 valid value. If you really don't want the block to have a
370 dictionary, then you should subsequently set its BLOCK_DICT to
371 dict_create_linear (obstack, NULL). */
374 allocate_block (struct obstack
*obstack
)
376 struct block
*bl
= OBSTACK_ZALLOC (obstack
, struct block
);
381 /* Allocate a global block. */
384 allocate_global_block (struct obstack
*obstack
)
386 struct global_block
*bl
= OBSTACK_ZALLOC (obstack
, struct global_block
);
391 /* Set the symtab of the global block. */
394 set_block_symtab (struct block
*block
, struct symtab
*symtab
)
396 struct global_block
*gb
;
398 gdb_assert (BLOCK_SUPERBLOCK (block
) == NULL
);
399 gb
= (struct global_block
*) block
;
400 gdb_assert (gb
->symtab
== NULL
);
404 /* Return the symtab of the global block. */
406 static struct symtab
*
407 get_block_symtab (const struct block
*block
)
409 struct global_block
*gb
;
411 gdb_assert (BLOCK_SUPERBLOCK (block
) == NULL
);
412 gb
= (struct global_block
*) block
;
413 gdb_assert (gb
->symtab
!= NULL
);
419 /* Initialize a block iterator, either to iterate over a single block,
420 or, for static and global blocks, all the included symtabs as
424 initialize_block_iterator (const struct block
*block
,
425 struct block_iterator
*iter
)
427 enum block_enum which
;
428 struct symtab
*symtab
;
432 if (BLOCK_SUPERBLOCK (block
) == NULL
)
434 which
= GLOBAL_BLOCK
;
435 symtab
= get_block_symtab (block
);
437 else if (BLOCK_SUPERBLOCK (BLOCK_SUPERBLOCK (block
)) == NULL
)
439 which
= STATIC_BLOCK
;
440 symtab
= get_block_symtab (BLOCK_SUPERBLOCK (block
));
444 iter
->d
.block
= block
;
445 /* A signal value meaning that we're iterating over a single
447 iter
->which
= FIRST_LOCAL_BLOCK
;
451 /* If this is an included symtab, find the canonical includer and
453 while (symtab
->user
!= NULL
)
454 symtab
= symtab
->user
;
456 /* Putting this check here simplifies the logic of the iterator
457 functions. If there are no included symtabs, we only need to
458 search a single block, so we might as well just do that
460 if (symtab
->includes
== NULL
)
462 iter
->d
.block
= block
;
463 /* A signal value meaning that we're iterating over a single
465 iter
->which
= FIRST_LOCAL_BLOCK
;
469 iter
->d
.symtab
= symtab
;
474 /* A helper function that finds the current symtab over whose static
475 or global block we should iterate. */
477 static struct symtab
*
478 find_iterator_symtab (struct block_iterator
*iterator
)
480 if (iterator
->idx
== -1)
481 return iterator
->d
.symtab
;
482 return iterator
->d
.symtab
->includes
[iterator
->idx
];
485 /* Perform a single step for a plain block iterator, iterating across
486 symbol tables as needed. Returns the next symbol, or NULL when
487 iteration is complete. */
489 static struct symbol
*
490 block_iterator_step (struct block_iterator
*iterator
, int first
)
494 gdb_assert (iterator
->which
!= FIRST_LOCAL_BLOCK
);
500 struct symtab
*symtab
= find_iterator_symtab (iterator
);
501 const struct block
*block
;
503 /* Iteration is complete. */
507 block
= BLOCKVECTOR_BLOCK (SYMTAB_BLOCKVECTOR (symtab
),
509 sym
= dict_iterator_first (BLOCK_DICT (block
), &iterator
->dict_iter
);
512 sym
= dict_iterator_next (&iterator
->dict_iter
);
517 /* We have finished iterating the appropriate block of one
518 symtab. Now advance to the next symtab and begin iteration
528 block_iterator_first (const struct block
*block
,
529 struct block_iterator
*iterator
)
531 initialize_block_iterator (block
, iterator
);
533 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
534 return dict_iterator_first (block
->dict
, &iterator
->dict_iter
);
536 return block_iterator_step (iterator
, 1);
542 block_iterator_next (struct block_iterator
*iterator
)
544 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
545 return dict_iterator_next (&iterator
->dict_iter
);
547 return block_iterator_step (iterator
, 0);
550 /* Perform a single step for a "name" block iterator, iterating across
551 symbol tables as needed. Returns the next symbol, or NULL when
552 iteration is complete. */
554 static struct symbol
*
555 block_iter_name_step (struct block_iterator
*iterator
, const char *name
,
560 gdb_assert (iterator
->which
!= FIRST_LOCAL_BLOCK
);
566 struct symtab
*symtab
= find_iterator_symtab (iterator
);
567 const struct block
*block
;
569 /* Iteration is complete. */
573 block
= BLOCKVECTOR_BLOCK (SYMTAB_BLOCKVECTOR (symtab
),
575 sym
= dict_iter_name_first (BLOCK_DICT (block
), name
,
576 &iterator
->dict_iter
);
579 sym
= dict_iter_name_next (name
, &iterator
->dict_iter
);
584 /* We have finished iterating the appropriate block of one
585 symtab. Now advance to the next symtab and begin iteration
595 block_iter_name_first (const struct block
*block
,
597 struct block_iterator
*iterator
)
599 initialize_block_iterator (block
, iterator
);
601 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
602 return dict_iter_name_first (block
->dict
, name
, &iterator
->dict_iter
);
604 return block_iter_name_step (iterator
, name
, 1);
610 block_iter_name_next (const char *name
, struct block_iterator
*iterator
)
612 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
613 return dict_iter_name_next (name
, &iterator
->dict_iter
);
615 return block_iter_name_step (iterator
, name
, 0);
618 /* Perform a single step for a "match" block iterator, iterating
619 across symbol tables as needed. Returns the next symbol, or NULL
620 when iteration is complete. */
622 static struct symbol
*
623 block_iter_match_step (struct block_iterator
*iterator
,
625 symbol_compare_ftype
*compare
,
630 gdb_assert (iterator
->which
!= FIRST_LOCAL_BLOCK
);
636 struct symtab
*symtab
= find_iterator_symtab (iterator
);
637 const struct block
*block
;
639 /* Iteration is complete. */
643 block
= BLOCKVECTOR_BLOCK (SYMTAB_BLOCKVECTOR (symtab
),
645 sym
= dict_iter_match_first (BLOCK_DICT (block
), name
,
646 compare
, &iterator
->dict_iter
);
649 sym
= dict_iter_match_next (name
, compare
, &iterator
->dict_iter
);
654 /* We have finished iterating the appropriate block of one
655 symtab. Now advance to the next symtab and begin iteration
665 block_iter_match_first (const struct block
*block
,
667 symbol_compare_ftype
*compare
,
668 struct block_iterator
*iterator
)
670 initialize_block_iterator (block
, iterator
);
672 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
673 return dict_iter_match_first (block
->dict
, name
, compare
,
674 &iterator
->dict_iter
);
676 return block_iter_match_step (iterator
, name
, compare
, 1);
682 block_iter_match_next (const char *name
,
683 symbol_compare_ftype
*compare
,
684 struct block_iterator
*iterator
)
686 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
687 return dict_iter_match_next (name
, compare
, &iterator
->dict_iter
);
689 return block_iter_match_step (iterator
, name
, compare
, 0);
694 Note that if NAME is the demangled form of a C++ symbol, we will fail
695 to find a match during the binary search of the non-encoded names, but
696 for now we don't worry about the slight inefficiency of looking for
697 a match we'll never find, since it will go pretty quick. Once the
698 binary search terminates, we drop through and do a straight linear
699 search on the symbols. Each symbol which is marked as being a ObjC/C++
700 symbol (language_cplus or language_objc set) has both the encoded and
701 non-encoded names tested for a match. */
704 block_lookup_symbol (const struct block
*block
, const char *name
,
705 const domain_enum domain
)
707 struct block_iterator iter
;
710 if (!BLOCK_FUNCTION (block
))
712 ALL_BLOCK_SYMBOLS_WITH_NAME (block
, name
, iter
, sym
)
714 if (symbol_matches_domain (SYMBOL_LANGUAGE (sym
),
715 SYMBOL_DOMAIN (sym
), domain
))
722 /* Note that parameter symbols do not always show up last in the
723 list; this loop makes sure to take anything else other than
724 parameter symbols first; it only uses parameter symbols as a
725 last resort. Note that this only takes up extra computation
728 struct symbol
*sym_found
= NULL
;
730 ALL_BLOCK_SYMBOLS_WITH_NAME (block
, name
, iter
, sym
)
732 if (symbol_matches_domain (SYMBOL_LANGUAGE (sym
),
733 SYMBOL_DOMAIN (sym
), domain
))
736 if (!SYMBOL_IS_ARGUMENT (sym
))
742 return (sym_found
); /* Will be NULL if not found. */