gdb/block.h

   1 /* Code dealing with blocks for GDB.
   2
   3    Copyright (C) 2003-2018 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   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.
  11
  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.
  16
  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/>.  */
  19
  20 #ifndef BLOCK_H
  21 #define BLOCK_H
  22
  23 #include "dictionary.h"
  24
  25 /* Opaque declarations.  */
  26
  27 struct symbol;
  28 struct compunit_symtab;
  29 struct block_namespace_info;
  30 struct using_direct;
  31 struct obstack;
  32 struct addrmap;
  33
  34 /* All of the name-scope contours of the program
  35    are represented by `struct block' objects.
  36    All of these objects are pointed to by the blockvector.
  37
  38    Each block represents one name scope.
  39    Each lexical context has its own block.
  40
  41    The blockvector begins with some special blocks.
  42    The GLOBAL_BLOCK contains all the symbols defined in this compilation
  43    whose scope is the entire program linked together.
  44    The STATIC_BLOCK contains all the symbols whose scope is the
  45    entire compilation excluding other separate compilations.
  46    Blocks starting with the FIRST_LOCAL_BLOCK are not special.
  47
  48    Each block records a range of core addresses for the code that
  49    is in the scope of the block.  The STATIC_BLOCK and GLOBAL_BLOCK
  50    give, for the range of code, the entire range of code produced
  51    by the compilation that the symbol segment belongs to.
  52
  53    The blocks appear in the blockvector
  54    in order of increasing starting-address,
  55    and, within that, in order of decreasing ending-address.
  56
  57    This implies that within the body of one function
  58    the blocks appear in the order of a depth-first tree walk.  */
  59
  60 struct block
  61 {
  62
  63   /* Addresses in the executable code that are in this block.  */
  64
  65   CORE_ADDR startaddr;
  66   CORE_ADDR endaddr;
  67
  68   /* The symbol that names this block, if the block is the body of a
  69      function (real or inlined); otherwise, zero.  */
  70
  71   struct symbol *function;
  72
  73   /* The `struct block' for the containing block, or 0 if none.
  74
  75      The superblock of a top-level local block (i.e. a function in the
  76      case of C) is the STATIC_BLOCK.  The superblock of the
  77      STATIC_BLOCK is the GLOBAL_BLOCK.  */
  78
  79   struct block *superblock;
  80
  81   /* This is used to store the symbols in the block.  */
  82
  83   struct dictionary *dict;
  84
  85   /* Contains information about namespace-related info relevant to this block:
  86      using directives and the current namespace scope.  */
  87
  88   struct block_namespace_info *namespace_info;
  89 };
  90
  91 /* The global block is singled out so that we can provide a back-link
  92    to the compunit symtab.  */
  93
  94 struct global_block
  95 {
  96   /* The block.  */
  97
  98   struct block block;
  99
 100   /* This holds a pointer to the compunit symtab holding this block.  */
 101
 102   struct compunit_symtab *compunit_symtab;
 103 };
 104
 105 #define BLOCK_START(bl)         (bl)->startaddr
 106 #define BLOCK_END(bl)           (bl)->endaddr
 107 #define BLOCK_FUNCTION(bl)      (bl)->function
 108 #define BLOCK_SUPERBLOCK(bl)    (bl)->superblock
 109 #define BLOCK_DICT(bl)          (bl)->dict
 110 #define BLOCK_NAMESPACE(bl)     (bl)->namespace_info
 111
 112 struct blockvector
 113 {
 114   /* Number of blocks in the list.  */
 115   int nblocks;
 116   /* An address map mapping addresses to blocks in this blockvector.
 117      This pointer is zero if the blocks' start and end addresses are
 118      enough.  */
 119   struct addrmap *map;
 120   /* The blocks themselves.  */
 121   struct block *block[1];
 122 };
 123
 124 #define BLOCKVECTOR_NBLOCKS(blocklist) (blocklist)->nblocks
 125 #define BLOCKVECTOR_BLOCK(blocklist,n) (blocklist)->block[n]
 126 #define BLOCKVECTOR_MAP(blocklist) ((blocklist)->map)
 127
 128 /* Return the objfile of BLOCK, which must be non-NULL.  */
 129
 130 extern struct objfile *block_objfile (const struct block *block);
 131
 132 /* Return the architecture of BLOCK, which must be non-NULL.  */
 133
 134 extern struct gdbarch *block_gdbarch (const struct block *block);
 135
 136 extern struct symbol *block_linkage_function (const struct block *);
 137
 138 extern struct symbol *block_containing_function (const struct block *);
 139
 140 extern int block_inlined_p (const struct block *block);
 141
 142 extern int contained_in (const struct block *, const struct block *);
 143
 144 extern const struct blockvector *blockvector_for_pc (CORE_ADDR,
 145                                                const struct block **);
 146
 147 extern const struct blockvector *
 148   blockvector_for_pc_sect (CORE_ADDR, struct obj_section *,
 149                            const struct block **, struct compunit_symtab *);
 150
 151 extern int blockvector_contains_pc (const struct blockvector *bv, CORE_ADDR pc);
 152
 153 extern struct call_site *call_site_for_pc (struct gdbarch *gdbarch,
 154                                            CORE_ADDR pc);
 155
 156 extern const struct block *block_for_pc (CORE_ADDR);
 157
 158 extern const struct block *block_for_pc_sect (CORE_ADDR, struct obj_section *);
 159
 160 extern const char *block_scope (const struct block *block);
 161
 162 extern void block_set_scope (struct block *block, const char *scope,
 163                              struct obstack *obstack);
 164
 165 extern struct using_direct *block_using (const struct block *block);
 166
 167 extern void block_set_using (struct block *block,
 168                              struct using_direct *using_decl,
 169                              struct obstack *obstack);
 170
 171 extern const struct block *block_static_block (const struct block *block);
 172
 173 extern const struct block *block_global_block (const struct block *block);
 174
 175 extern struct block *allocate_block (struct obstack *obstack);
 176
 177 extern struct block *allocate_global_block (struct obstack *obstack);
 178
 179 extern void set_block_compunit_symtab (struct block *,
 180                                        struct compunit_symtab *);
 181
 182 /* Return a property to evaluate the static link associated to BLOCK.
 183
 184    In the context of nested functions (available in Pascal, Ada and GNU C, for
 185    instance), a static link (as in DWARF's DW_AT_static_link attribute) for a
 186    function is a way to get the frame corresponding to the enclosing function.
 187
 188    Note that only objfile-owned and function-level blocks can have a static
 189    link.  Return NULL if there is no such property.  */
 190
 191 extern struct dynamic_prop *block_static_link (const struct block *block);
 192
 193 /* A block iterator.  This structure should be treated as though it
 194    were opaque; it is only defined here because we want to support
 195    stack allocation of iterators.  */
 196
 197 struct block_iterator
 198 {
 199   /* If we're iterating over a single block, this holds the block.
 200      Otherwise, it holds the canonical compunit.  */
 201
 202   union
 203   {
 204     struct compunit_symtab *compunit_symtab;
 205     const struct block *block;
 206   } d;
 207
 208   /* If we're iterating over a single block, this is always -1.
 209      Otherwise, it holds the index of the current "included" symtab in
 210      the canonical symtab (that is, d.symtab->includes[idx]), with -1
 211      meaning the canonical symtab itself.  */
 212
 213   int idx;
 214
 215   /* Which block, either static or global, to iterate over.  If this
 216      is FIRST_LOCAL_BLOCK, then we are iterating over a single block.
 217      This is used to select which field of 'd' is in use.  */
 218
 219   enum block_enum which;
 220
 221   /* The underlying dictionary iterator.  */
 222
 223   struct dict_iterator dict_iter;
 224 };
 225
 226 /* Initialize ITERATOR to point at the first symbol in BLOCK, and
 227    return that first symbol, or NULL if BLOCK is empty.  */
 228
 229 extern struct symbol *block_iterator_first (const struct block *block,
 230                                             struct block_iterator *iterator);
 231
 232 /* Advance ITERATOR, and return the next symbol, or NULL if there are
 233    no more symbols.  Don't call this if you've previously received
 234    NULL from block_iterator_first or block_iterator_next on this
 235    iteration.  */
 236
 237 extern struct symbol *block_iterator_next (struct block_iterator *iterator);
 238
 239 /* Initialize ITERATOR to point at the first symbol in BLOCK whose
 240    SYMBOL_SEARCH_NAME matches NAME, and return that first symbol, or
 241    NULL if there are no such symbols.  */
 242
 243 extern struct symbol *block_iter_match_first (const struct block *block,
 244                                               const lookup_name_info &name,
 245                                               struct block_iterator *iterator);
 246
 247 /* Advance ITERATOR to point at the next symbol in BLOCK whose
 248    SYMBOL_SEARCH_NAME matches NAME, or NULL if there are no more such
 249    symbols.  Don't call this if you've previously received NULL from
 250    block_iterator_match_first or block_iterator_match_next on this
 251    iteration.  And don't call it unless ITERATOR was created by a
 252    previous call to block_iter_match_first with the same NAME.  */
 253
 254 extern struct symbol *block_iter_match_next
 255   (const lookup_name_info &name, struct block_iterator *iterator);
 256
 257 /* Search BLOCK for symbol NAME in DOMAIN.  */
 258
 259 extern struct symbol *block_lookup_symbol (const struct block *block,
 260                                            const char *name,
 261                                            symbol_name_match_type match_type,
 262                                            const domain_enum domain);
 263
 264 /* Search BLOCK for symbol NAME in DOMAIN but only in primary symbol table of
 265    BLOCK.  BLOCK must be STATIC_BLOCK or GLOBAL_BLOCK.  Function is useful if
 266    one iterates all global/static blocks of an objfile.  */
 267
 268 extern struct symbol *block_lookup_symbol_primary (const struct block *block,
 269                                                    const char *name,
 270                                                    const domain_enum domain);
 271
 272 /* The type of the MATCHER argument to block_find_symbol.  */
 273
 274 typedef int (block_symbol_matcher_ftype) (struct symbol *, void *);
 275
 276 /* Find symbol NAME in BLOCK and in DOMAIN that satisfies MATCHER.
 277    DATA is passed unchanged to MATCHER.
 278    BLOCK must be STATIC_BLOCK or GLOBAL_BLOCK.  */
 279
 280 extern struct symbol *block_find_symbol (const struct block *block,
 281                                          const char *name,
 282                                          const domain_enum domain,
 283                                          block_symbol_matcher_ftype *matcher,
 284                                          void *data);
 285
 286 /* A matcher function for block_find_symbol to find only symbols with
 287    non-opaque types.  */
 288
 289 extern int block_find_non_opaque_type (struct symbol *sym, void *data);
 290
 291 /* A matcher function for block_find_symbol to prefer symbols with
 292    non-opaque types.  The way to use this function is as follows:
 293
 294    struct symbol *with_opaque = NULL;
 295    struct symbol *sym
 296      = block_find_symbol (block, name, domain,
 297                           block_find_non_opaque_type_preferred, &with_opaque);
 298
 299    At this point if SYM is non-NULL then a non-opaque type has been found.
 300    Otherwise, if WITH_OPAQUE is non-NULL then an opaque type has been found.
 301    Otherwise, the symbol was not found.  */
 302
 303 extern int block_find_non_opaque_type_preferred (struct symbol *sym,
 304                                                  void *data);
 305
 306 /* Macro to loop through all symbols in BLOCK, in no particular
 307    order.  ITER helps keep track of the iteration, and must be a
 308    struct block_iterator.  SYM points to the current symbol.  */
 309
 310 #define ALL_BLOCK_SYMBOLS(block, iter, sym)             \
 311   for ((sym) = block_iterator_first ((block), &(iter)); \
 312        (sym);                                           \
 313        (sym) = block_iterator_next (&(iter)))
 314
 315 /* Macro to loop through all symbols in BLOCK with a name that matches
 316    NAME, in no particular order.  ITER helps keep track of the
 317    iteration, and must be a struct block_iterator.  SYM points to the
 318    current symbol.  */
 319
 320 #define ALL_BLOCK_SYMBOLS_WITH_NAME(block, name, iter, sym)             \
 321   for ((sym) = block_iter_match_first ((block), (name), &(iter));       \
 322        (sym) != NULL;                                                   \
 323        (sym) = block_iter_match_next ((name), &(iter)))
 324
 325 #endif /* BLOCK_H */