1 /* Code dealing with blocks for GDB.
3 Copyright (C) 2003-2022 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/>. */
23 #include "dictionary.h"
24 #include "gdbsupport/array-view.h"
26 /* Opaque declarations. */
29 struct compunit_symtab
;
30 struct block_namespace_info
;
35 /* Blocks can occupy non-contiguous address ranges. When this occurs,
36 startaddr and endaddr within struct block (still) specify the lowest
37 and highest addresses of all ranges, but each individual range is
38 specified by the addresses in struct blockrange. */
42 blockrange (CORE_ADDR start
, CORE_ADDR end
)
48 /* Return this blockrange's start address. */
49 CORE_ADDR
start () const
52 /* Set this blockrange's start address. */
53 void set_start (CORE_ADDR start
)
56 /* Return this blockrange's end address. */
57 CORE_ADDR
end () const
60 /* Set this blockrange's end address. */
61 void set_end (CORE_ADDR end
)
64 /* Lowest address in this range. */
68 /* One past the highest address in the range. */
73 /* Two or more non-contiguous ranges in the same order as that provided
74 via the debug info. */
79 struct blockrange range
[1];
82 /* All of the name-scope contours of the program
83 are represented by `struct block' objects.
84 All of these objects are pointed to by the blockvector.
86 Each block represents one name scope.
87 Each lexical context has its own block.
89 The blockvector begins with some special blocks.
90 The GLOBAL_BLOCK contains all the symbols defined in this compilation
91 whose scope is the entire program linked together.
92 The STATIC_BLOCK contains all the symbols whose scope is the
93 entire compilation excluding other separate compilations.
94 Blocks starting with the FIRST_LOCAL_BLOCK are not special.
96 Each block records a range of core addresses for the code that
97 is in the scope of the block. The STATIC_BLOCK and GLOBAL_BLOCK
98 give, for the range of code, the entire range of code produced
99 by the compilation that the symbol segment belongs to.
101 The blocks appear in the blockvector
102 in order of increasing starting-address,
103 and, within that, in order of decreasing ending-address.
105 This implies that within the body of one function
106 the blocks appear in the order of a depth-first tree walk. */
110 /* Return this block's start address. */
111 CORE_ADDR
start () const
114 /* Set this block's start address. */
115 void set_start (CORE_ADDR start
)
118 /* Return this block's end address. */
119 CORE_ADDR
end () const
122 /* Set this block's end address. */
123 void set_end (CORE_ADDR end
)
126 /* Return this block's function symbol. */
127 symbol
*function () const
128 { return m_function
; }
130 /* Set this block's function symbol. */
131 void set_function (symbol
*function
)
132 { m_function
= function
; }
134 /* Return this block's superblock. */
135 const block
*superblock () const
136 { return m_superblock
; }
138 /* Set this block's superblock. */
139 void set_superblock (const block
*superblock
)
140 { m_superblock
= superblock
; }
142 /* Return this block's multidict. */
143 multidictionary
*multidict () const
144 { return m_multidict
; }
146 /* Set this block's multidict. */
147 void set_multidict (multidictionary
*multidict
)
148 { m_multidict
= multidict
; }
150 /* Return this block's namespace info. */
151 block_namespace_info
*namespace_info () const
152 { return m_namespace_info
; }
154 /* Set this block's namespace info. */
155 void set_namespace_info (block_namespace_info
*namespace_info
)
156 { m_namespace_info
= namespace_info
; }
158 /* Return a view on this block's ranges. */
159 gdb::array_view
<blockrange
> ranges ()
160 { return gdb::make_array_view (m_ranges
->range
, m_ranges
->nranges
); }
162 /* Const version of the above. */
163 gdb::array_view
<const blockrange
> ranges () const
164 { return gdb::make_array_view (m_ranges
->range
, m_ranges
->nranges
); }
166 /* Set this block's ranges array. */
167 void set_ranges (blockranges
*ranges
)
168 { m_ranges
= ranges
; }
170 /* Return true if all addresses within this block are contiguous. */
171 bool is_contiguous () const
172 { return this->ranges ().size () <= 1; }
174 /* Addresses in the executable code that are in this block. */
179 /* The symbol that names this block, if the block is the body of a
180 function (real or inlined); otherwise, zero. */
182 struct symbol
*m_function
;
184 /* The `struct block' for the containing block, or 0 if none.
186 The superblock of a top-level local block (i.e. a function in the
187 case of C) is the STATIC_BLOCK. The superblock of the
188 STATIC_BLOCK is the GLOBAL_BLOCK. */
190 const struct block
*m_superblock
;
192 /* This is used to store the symbols in the block. */
194 struct multidictionary
*m_multidict
;
196 /* Contains information about namespace-related info relevant to this block:
197 using directives and the current namespace scope. */
199 struct block_namespace_info
*m_namespace_info
;
201 /* Address ranges for blocks with non-contiguous ranges. If this
202 is NULL, then there is only one range which is specified by
203 startaddr and endaddr above. */
205 struct blockranges
*m_ranges
;
208 /* The global block is singled out so that we can provide a back-link
209 to the compunit symtab. */
217 /* This holds a pointer to the compunit symtab holding this block. */
219 struct compunit_symtab
*compunit_symtab
;
222 /* Define the "entry pc" for a block BL to be the lowest (start) address
223 for the block when all addresses within the block are contiguous. If
224 non-contiguous, then use the start address for the first range in the
227 At the moment, this almost matches what DWARF specifies as the entry
228 pc. (The missing bit is support for DW_AT_entry_pc which should be
229 preferred over range data and the low_pc.)
231 Once support for DW_AT_entry_pc is added, I expect that an entry_pc
232 field will be added to one of these data structures. Once that's done,
233 the entry_pc field can be set from the dwarf reader (and other readers
234 too). BLOCK_ENTRY_PC can then be redefined to be less DWARF-centric. */
236 #define BLOCK_ENTRY_PC(bl) (bl->is_contiguous () \
238 : bl->ranges ()[0].start ())
242 /* Number of blocks in the list. */
244 /* An address map mapping addresses to blocks in this blockvector.
245 This pointer is zero if the blocks' start and end addresses are
248 /* The blocks themselves. */
249 struct block
*block
[1];
252 #define BLOCKVECTOR_NBLOCKS(blocklist) (blocklist)->nblocks
253 #define BLOCKVECTOR_BLOCK(blocklist,n) (blocklist)->block[n]
254 #define BLOCKVECTOR_MAP(blocklist) ((blocklist)->map)
256 /* Return the objfile of BLOCK, which must be non-NULL. */
258 extern struct objfile
*block_objfile (const struct block
*block
);
260 /* Return the architecture of BLOCK, which must be non-NULL. */
262 extern struct gdbarch
*block_gdbarch (const struct block
*block
);
264 extern struct symbol
*block_linkage_function (const struct block
*);
266 extern struct symbol
*block_containing_function (const struct block
*);
268 extern int block_inlined_p (const struct block
*block
);
270 /* Return true if block A is lexically nested within block B, or if a
271 and b have the same pc range. Return false otherwise. If
272 ALLOW_NESTED is true, then block A is considered to be in block B
273 if A is in a nested function in B's function. If ALLOW_NESTED is
274 false (the default), then blocks in nested functions are not
275 considered to be contained. */
277 extern bool contained_in (const struct block
*a
, const struct block
*b
,
278 bool allow_nested
= false);
280 extern const struct blockvector
*blockvector_for_pc (CORE_ADDR
,
281 const struct block
**);
283 extern const struct blockvector
*
284 blockvector_for_pc_sect (CORE_ADDR
, struct obj_section
*,
285 const struct block
**, struct compunit_symtab
*);
287 extern int blockvector_contains_pc (const struct blockvector
*bv
, CORE_ADDR pc
);
289 extern struct call_site
*call_site_for_pc (struct gdbarch
*gdbarch
,
292 extern const struct block
*block_for_pc (CORE_ADDR
);
294 extern const struct block
*block_for_pc_sect (CORE_ADDR
, struct obj_section
*);
296 extern const char *block_scope (const struct block
*block
);
298 extern void block_set_scope (struct block
*block
, const char *scope
,
299 struct obstack
*obstack
);
301 extern struct using_direct
*block_using (const struct block
*block
);
303 extern void block_set_using (struct block
*block
,
304 struct using_direct
*using_decl
,
305 struct obstack
*obstack
);
307 extern const struct block
*block_static_block (const struct block
*block
);
309 extern const struct block
*block_global_block (const struct block
*block
);
311 extern struct block
*allocate_block (struct obstack
*obstack
);
313 extern struct block
*allocate_global_block (struct obstack
*obstack
);
315 extern void set_block_compunit_symtab (struct block
*,
316 struct compunit_symtab
*);
318 /* Return a property to evaluate the static link associated to BLOCK.
320 In the context of nested functions (available in Pascal, Ada and GNU C, for
321 instance), a static link (as in DWARF's DW_AT_static_link attribute) for a
322 function is a way to get the frame corresponding to the enclosing function.
324 Note that only objfile-owned and function-level blocks can have a static
325 link. Return NULL if there is no such property. */
327 extern struct dynamic_prop
*block_static_link (const struct block
*block
);
329 /* A block iterator. This structure should be treated as though it
330 were opaque; it is only defined here because we want to support
331 stack allocation of iterators. */
333 struct block_iterator
335 /* If we're iterating over a single block, this holds the block.
336 Otherwise, it holds the canonical compunit. */
340 struct compunit_symtab
*compunit_symtab
;
341 const struct block
*block
;
344 /* If we're iterating over a single block, this is always -1.
345 Otherwise, it holds the index of the current "included" symtab in
346 the canonical symtab (that is, d.symtab->includes[idx]), with -1
347 meaning the canonical symtab itself. */
351 /* Which block, either static or global, to iterate over. If this
352 is FIRST_LOCAL_BLOCK, then we are iterating over a single block.
353 This is used to select which field of 'd' is in use. */
355 enum block_enum which
;
357 /* The underlying multidictionary iterator. */
359 struct mdict_iterator mdict_iter
;
362 /* Initialize ITERATOR to point at the first symbol in BLOCK, and
363 return that first symbol, or NULL if BLOCK is empty. */
365 extern struct symbol
*block_iterator_first (const struct block
*block
,
366 struct block_iterator
*iterator
);
368 /* Advance ITERATOR, and return the next symbol, or NULL if there are
369 no more symbols. Don't call this if you've previously received
370 NULL from block_iterator_first or block_iterator_next on this
373 extern struct symbol
*block_iterator_next (struct block_iterator
*iterator
);
375 /* Initialize ITERATOR to point at the first symbol in BLOCK whose
376 search_name () matches NAME, and return that first symbol, or
377 NULL if there are no such symbols. */
379 extern struct symbol
*block_iter_match_first (const struct block
*block
,
380 const lookup_name_info
&name
,
381 struct block_iterator
*iterator
);
383 /* Advance ITERATOR to point at the next symbol in BLOCK whose
384 search_name () matches NAME, or NULL if there are no more such
385 symbols. Don't call this if you've previously received NULL from
386 block_iterator_match_first or block_iterator_match_next on this
387 iteration. And don't call it unless ITERATOR was created by a
388 previous call to block_iter_match_first with the same NAME. */
390 extern struct symbol
*block_iter_match_next
391 (const lookup_name_info
&name
, struct block_iterator
*iterator
);
393 /* Return true if symbol A is the best match possible for DOMAIN. */
395 extern bool best_symbol (struct symbol
*a
, const domain_enum domain
);
397 /* Return symbol B if it is a better match than symbol A for DOMAIN.
398 Otherwise return A. */
400 extern struct symbol
*better_symbol (struct symbol
*a
, struct symbol
*b
,
401 const domain_enum domain
);
403 /* Search BLOCK for symbol NAME in DOMAIN. */
405 extern struct symbol
*block_lookup_symbol (const struct block
*block
,
407 symbol_name_match_type match_type
,
408 const domain_enum domain
);
410 /* Search BLOCK for symbol NAME in DOMAIN but only in primary symbol table of
411 BLOCK. BLOCK must be STATIC_BLOCK or GLOBAL_BLOCK. Function is useful if
412 one iterates all global/static blocks of an objfile. */
414 extern struct symbol
*block_lookup_symbol_primary (const struct block
*block
,
416 const domain_enum domain
);
418 /* The type of the MATCHER argument to block_find_symbol. */
420 typedef int (block_symbol_matcher_ftype
) (struct symbol
*, void *);
422 /* Find symbol NAME in BLOCK and in DOMAIN that satisfies MATCHER.
423 DATA is passed unchanged to MATCHER.
424 BLOCK must be STATIC_BLOCK or GLOBAL_BLOCK. */
426 extern struct symbol
*block_find_symbol (const struct block
*block
,
428 const domain_enum domain
,
429 block_symbol_matcher_ftype
*matcher
,
432 /* A matcher function for block_find_symbol to find only symbols with
435 extern int block_find_non_opaque_type (struct symbol
*sym
, void *data
);
437 /* A matcher function for block_find_symbol to prefer symbols with
438 non-opaque types. The way to use this function is as follows:
440 struct symbol *with_opaque = NULL;
442 = block_find_symbol (block, name, domain,
443 block_find_non_opaque_type_preferred, &with_opaque);
445 At this point if SYM is non-NULL then a non-opaque type has been found.
446 Otherwise, if WITH_OPAQUE is non-NULL then an opaque type has been found.
447 Otherwise, the symbol was not found. */
449 extern int block_find_non_opaque_type_preferred (struct symbol
*sym
,
452 /* Macro to loop through all symbols in BLOCK, in no particular
453 order. ITER helps keep track of the iteration, and must be a
454 struct block_iterator. SYM points to the current symbol. */
456 #define ALL_BLOCK_SYMBOLS(block, iter, sym) \
457 for ((sym) = block_iterator_first ((block), &(iter)); \
459 (sym) = block_iterator_next (&(iter)))
461 /* Macro to loop through all symbols in BLOCK with a name that matches
462 NAME, in no particular order. ITER helps keep track of the
463 iteration, and must be a struct block_iterator. SYM points to the
466 #define ALL_BLOCK_SYMBOLS_WITH_NAME(block, name, iter, sym) \
467 for ((sym) = block_iter_match_first ((block), (name), &(iter)); \
469 (sym) = block_iter_match_next ((name), &(iter)))
471 /* Given a vector of pairs, allocate and build an obstack allocated
472 blockranges struct for a block. */
473 struct blockranges
*make_blockranges (struct objfile
*objfile
,
474 const std::vector
<blockrange
> &rangevec
);