1 /* Block-related functions for the GNU debugger, GDB.
3 Copyright (C) 2003-2013 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"
28 #include "exceptions.h"
30 /* This is used by struct block to store namespace-related info for
31 C++ files, namely using declarations and the current namespace in
34 struct block_namespace_info
37 struct using_direct
*using;
40 static void block_initialize_namespace (struct block
*block
,
41 struct obstack
*obstack
);
43 /* Return Nonzero if block a is lexically nested within block b,
44 or if a and b have the same pc range.
45 Return zero otherwise. */
48 contained_in (const struct block
*a
, const struct block
*b
)
57 /* If A is a function block, then A cannot be contained in B,
58 except if A was inlined. */
59 if (BLOCK_FUNCTION (a
) != NULL
&& !block_inlined_p (a
))
61 a
= BLOCK_SUPERBLOCK (a
);
69 /* Return the symbol for the function which contains a specified
70 lexical block, described by a struct block BL. The return value
71 will not be an inlined function; the containing function will be
75 block_linkage_function (const struct block
*bl
)
77 while ((BLOCK_FUNCTION (bl
) == NULL
|| block_inlined_p (bl
))
78 && BLOCK_SUPERBLOCK (bl
) != NULL
)
79 bl
= BLOCK_SUPERBLOCK (bl
);
81 return BLOCK_FUNCTION (bl
);
84 /* Return the symbol for the function which contains a specified
85 block, described by a struct block BL. The return value will be
86 the closest enclosing function, which might be an inline
90 block_containing_function (const struct block
*bl
)
92 while (BLOCK_FUNCTION (bl
) == NULL
&& BLOCK_SUPERBLOCK (bl
) != NULL
)
93 bl
= BLOCK_SUPERBLOCK (bl
);
95 return BLOCK_FUNCTION (bl
);
98 /* Return one if BL represents an inlined function. */
101 block_inlined_p (const struct block
*bl
)
103 return BLOCK_FUNCTION (bl
) != NULL
&& SYMBOL_INLINED (BLOCK_FUNCTION (bl
));
106 /* A helper function that checks whether PC is in the blockvector BL.
107 It returns the containing block if there is one, or else NULL. */
109 static struct block
*
110 find_block_in_blockvector (struct blockvector
*bl
, CORE_ADDR pc
)
115 /* If we have an addrmap mapping code addresses to blocks, then use
117 if (BLOCKVECTOR_MAP (bl
))
118 return addrmap_find (BLOCKVECTOR_MAP (bl
), pc
);
120 /* Otherwise, use binary search to find the last block that starts
122 Note: GLOBAL_BLOCK is block 0, STATIC_BLOCK is block 1.
123 They both have the same START,END values.
124 Historically this code would choose STATIC_BLOCK over GLOBAL_BLOCK but the
125 fact that this choice was made was subtle, now we make it explicit. */
126 gdb_assert (BLOCKVECTOR_NBLOCKS (bl
) >= 2);
128 top
= BLOCKVECTOR_NBLOCKS (bl
);
130 while (top
- bot
> 1)
132 half
= (top
- bot
+ 1) >> 1;
133 b
= BLOCKVECTOR_BLOCK (bl
, bot
+ half
);
134 if (BLOCK_START (b
) <= pc
)
140 /* Now search backward for a block that ends after PC. */
142 while (bot
>= STATIC_BLOCK
)
144 b
= BLOCKVECTOR_BLOCK (bl
, bot
);
145 if (BLOCK_END (b
) > pc
)
153 /* Return the blockvector immediately containing the innermost lexical
154 block containing the specified pc value and section, or 0 if there
155 is none. PBLOCK is a pointer to the block. If PBLOCK is NULL, we
156 don't pass this information back to the caller. */
159 blockvector_for_pc_sect (CORE_ADDR pc
, struct obj_section
*section
,
160 struct block
**pblock
, struct symtab
*symtab
)
162 struct blockvector
*bl
;
165 if (symtab
== 0) /* if no symtab specified by caller */
167 /* First search all symtabs for one whose file contains our pc */
168 symtab
= find_pc_sect_symtab (pc
, section
);
173 bl
= BLOCKVECTOR (symtab
);
175 /* Then search that symtab for the smallest block that wins. */
176 b
= find_block_in_blockvector (bl
, pc
);
185 /* Return true if the blockvector BV contains PC, false otherwise. */
188 blockvector_contains_pc (struct blockvector
*bv
, CORE_ADDR pc
)
190 return find_block_in_blockvector (bv
, pc
) != NULL
;
193 /* Return call_site for specified PC in GDBARCH. PC must match exactly, it
194 must be the next instruction after call (or after tail call jump). Throw
195 NO_ENTRY_VALUE_ERROR otherwise. This function never returns NULL. */
198 call_site_for_pc (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
200 struct symtab
*symtab
;
203 /* -1 as tail call PC can be already after the compilation unit range. */
204 symtab
= find_pc_symtab (pc
- 1);
206 if (symtab
!= NULL
&& symtab
->call_site_htab
!= NULL
)
207 slot
= htab_find_slot (symtab
->call_site_htab
, &pc
, NO_INSERT
);
211 struct minimal_symbol
*msym
= lookup_minimal_symbol_by_pc (pc
);
213 /* DW_TAG_gnu_call_site will be missing just if GCC could not determine
215 throw_error (NO_ENTRY_VALUE_ERROR
,
216 _("DW_OP_GNU_entry_value resolving cannot find "
217 "DW_TAG_GNU_call_site %s in %s"),
218 paddress (gdbarch
, pc
),
219 msym
== NULL
? "???" : SYMBOL_PRINT_NAME (msym
));
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. */
230 blockvector_for_pc (CORE_ADDR pc
, 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 struct blockvector
*bl
;
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_alloc (obstack
, sizeof (struct block
));
378 BLOCK_START (bl
) = 0;
380 BLOCK_FUNCTION (bl
) = NULL
;
381 BLOCK_SUPERBLOCK (bl
) = NULL
;
382 BLOCK_DICT (bl
) = NULL
;
383 BLOCK_NAMESPACE (bl
) = NULL
;
388 /* Allocate a global block. */
391 allocate_global_block (struct obstack
*obstack
)
393 struct global_block
*bl
= OBSTACK_ZALLOC (obstack
, struct global_block
);
398 /* Set the symtab of the global block. */
401 set_block_symtab (struct block
*block
, struct symtab
*symtab
)
403 struct global_block
*gb
;
405 gdb_assert (BLOCK_SUPERBLOCK (block
) == NULL
);
406 gb
= (struct global_block
*) block
;
407 gdb_assert (gb
->symtab
== NULL
);
411 /* Return the symtab of the global block. */
413 static struct symtab
*
414 get_block_symtab (const struct block
*block
)
416 struct global_block
*gb
;
418 gdb_assert (BLOCK_SUPERBLOCK (block
) == NULL
);
419 gb
= (struct global_block
*) block
;
420 gdb_assert (gb
->symtab
!= NULL
);
426 /* Initialize a block iterator, either to iterate over a single block,
427 or, for static and global blocks, all the included symtabs as
431 initialize_block_iterator (const struct block
*block
,
432 struct block_iterator
*iter
)
434 enum block_enum which
;
435 struct symtab
*symtab
;
439 if (BLOCK_SUPERBLOCK (block
) == NULL
)
441 which
= GLOBAL_BLOCK
;
442 symtab
= get_block_symtab (block
);
444 else if (BLOCK_SUPERBLOCK (BLOCK_SUPERBLOCK (block
)) == NULL
)
446 which
= STATIC_BLOCK
;
447 symtab
= get_block_symtab (BLOCK_SUPERBLOCK (block
));
451 iter
->d
.block
= block
;
452 /* A signal value meaning that we're iterating over a single
454 iter
->which
= FIRST_LOCAL_BLOCK
;
458 /* If this is an included symtab, find the canonical includer and
460 while (symtab
->user
!= NULL
)
461 symtab
= symtab
->user
;
463 /* Putting this check here simplifies the logic of the iterator
464 functions. If there are no included symtabs, we only need to
465 search a single block, so we might as well just do that
467 if (symtab
->includes
== NULL
)
469 iter
->d
.block
= block
;
470 /* A signal value meaning that we're iterating over a single
472 iter
->which
= FIRST_LOCAL_BLOCK
;
476 iter
->d
.symtab
= symtab
;
481 /* A helper function that finds the current symtab over whose static
482 or global block we should iterate. */
484 static struct symtab
*
485 find_iterator_symtab (struct block_iterator
*iterator
)
487 if (iterator
->idx
== -1)
488 return iterator
->d
.symtab
;
489 return iterator
->d
.symtab
->includes
[iterator
->idx
];
492 /* Perform a single step for a plain block iterator, iterating across
493 symbol tables as needed. Returns the next symbol, or NULL when
494 iteration is complete. */
496 static struct symbol
*
497 block_iterator_step (struct block_iterator
*iterator
, int first
)
501 gdb_assert (iterator
->which
!= FIRST_LOCAL_BLOCK
);
507 struct symtab
*symtab
= find_iterator_symtab (iterator
);
508 const struct block
*block
;
510 /* Iteration is complete. */
514 block
= BLOCKVECTOR_BLOCK (BLOCKVECTOR (symtab
), iterator
->which
);
515 sym
= dict_iterator_first (BLOCK_DICT (block
), &iterator
->dict_iter
);
518 sym
= dict_iterator_next (&iterator
->dict_iter
);
523 /* We have finished iterating the appropriate block of one
524 symtab. Now advance to the next symtab and begin iteration
534 block_iterator_first (const struct block
*block
,
535 struct block_iterator
*iterator
)
537 initialize_block_iterator (block
, iterator
);
539 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
540 return dict_iterator_first (block
->dict
, &iterator
->dict_iter
);
542 return block_iterator_step (iterator
, 1);
548 block_iterator_next (struct block_iterator
*iterator
)
550 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
551 return dict_iterator_next (&iterator
->dict_iter
);
553 return block_iterator_step (iterator
, 0);
556 /* Perform a single step for a "name" block iterator, iterating across
557 symbol tables as needed. Returns the next symbol, or NULL when
558 iteration is complete. */
560 static struct symbol
*
561 block_iter_name_step (struct block_iterator
*iterator
, const char *name
,
566 gdb_assert (iterator
->which
!= FIRST_LOCAL_BLOCK
);
572 struct symtab
*symtab
= find_iterator_symtab (iterator
);
573 const struct block
*block
;
575 /* Iteration is complete. */
579 block
= BLOCKVECTOR_BLOCK (BLOCKVECTOR (symtab
), iterator
->which
);
580 sym
= dict_iter_name_first (BLOCK_DICT (block
), name
,
581 &iterator
->dict_iter
);
584 sym
= dict_iter_name_next (name
, &iterator
->dict_iter
);
589 /* We have finished iterating the appropriate block of one
590 symtab. Now advance to the next symtab and begin iteration
600 block_iter_name_first (const struct block
*block
,
602 struct block_iterator
*iterator
)
604 initialize_block_iterator (block
, iterator
);
606 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
607 return dict_iter_name_first (block
->dict
, name
, &iterator
->dict_iter
);
609 return block_iter_name_step (iterator
, name
, 1);
615 block_iter_name_next (const char *name
, struct block_iterator
*iterator
)
617 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
618 return dict_iter_name_next (name
, &iterator
->dict_iter
);
620 return block_iter_name_step (iterator
, name
, 0);
623 /* Perform a single step for a "match" block iterator, iterating
624 across symbol tables as needed. Returns the next symbol, or NULL
625 when iteration is complete. */
627 static struct symbol
*
628 block_iter_match_step (struct block_iterator
*iterator
,
630 symbol_compare_ftype
*compare
,
635 gdb_assert (iterator
->which
!= FIRST_LOCAL_BLOCK
);
641 struct symtab
*symtab
= find_iterator_symtab (iterator
);
642 const struct block
*block
;
644 /* Iteration is complete. */
648 block
= BLOCKVECTOR_BLOCK (BLOCKVECTOR (symtab
), iterator
->which
);
649 sym
= dict_iter_match_first (BLOCK_DICT (block
), name
,
650 compare
, &iterator
->dict_iter
);
653 sym
= dict_iter_match_next (name
, compare
, &iterator
->dict_iter
);
658 /* We have finished iterating the appropriate block of one
659 symtab. Now advance to the next symtab and begin iteration
669 block_iter_match_first (const struct block
*block
,
671 symbol_compare_ftype
*compare
,
672 struct block_iterator
*iterator
)
674 initialize_block_iterator (block
, iterator
);
676 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
677 return dict_iter_match_first (block
->dict
, name
, compare
,
678 &iterator
->dict_iter
);
680 return block_iter_match_step (iterator
, name
, compare
, 1);
686 block_iter_match_next (const char *name
,
687 symbol_compare_ftype
*compare
,
688 struct block_iterator
*iterator
)
690 if (iterator
->which
== FIRST_LOCAL_BLOCK
)
691 return dict_iter_match_next (name
, compare
, &iterator
->dict_iter
);
693 return block_iter_match_step (iterator
, name
, compare
, 0);