gdb/block.h

   1 /* Code dealing with blocks for GDB.
   2
   3    Copyright (C) 2003, 2007-2012 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 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   /* Used for language-specific info.  */
  86
  87   union
  88   {
  89     struct
  90     {
  91       /* Contains information about namespace-related info relevant to
  92          this block: using directives and the current namespace
  93          scope.  */
  94
  95       struct block_namespace_info *namespace;
  96     }
  97     cplus_specific;
  98   }
  99   language_specific;
 100 };
 101
 102 /* The global block is singled out so that we can provide a back-link
 103    to the primary symtab.  */
 104
 105 struct global_block
 106 {
 107   /* The block.  */
 108
 109   struct block block;
 110
 111   /* This holds a pointer to the primary symtab holding this
 112      block.  */
 113
 114   struct symtab *symtab;
 115 };
 116
 117 #define BLOCK_START(bl)         (bl)->startaddr
 118 #define BLOCK_END(bl)           (bl)->endaddr
 119 #define BLOCK_FUNCTION(bl)      (bl)->function
 120 #define BLOCK_SUPERBLOCK(bl)    (bl)->superblock
 121 #define BLOCK_DICT(bl)          (bl)->dict
 122 #define BLOCK_NAMESPACE(bl)   (bl)->language_specific.cplus_specific.namespace
 123
 124 struct blockvector
 125 {
 126   /* Number of blocks in the list.  */
 127   int nblocks;
 128   /* An address map mapping addresses to blocks in this blockvector.
 129      This pointer is zero if the blocks' start and end addresses are
 130      enough.  */
 131   struct addrmap *map;
 132   /* The blocks themselves.  */
 133   struct block *block[1];
 134 };
 135
 136 #define BLOCKVECTOR_NBLOCKS(blocklist) (blocklist)->nblocks
 137 #define BLOCKVECTOR_BLOCK(blocklist,n) (blocklist)->block[n]
 138 #define BLOCKVECTOR_MAP(blocklist) ((blocklist)->map)
 139
 140 extern struct symbol *block_linkage_function (const struct block *);
 141
 142 extern struct symbol *block_containing_function (const struct block *);
 143
 144 extern int block_inlined_p (const struct block *block);
 145
 146 extern int contained_in (const struct block *, const struct block *);
 147
 148 extern struct blockvector *blockvector_for_pc (CORE_ADDR, struct block **);
 149
 150 extern struct blockvector *blockvector_for_pc_sect (CORE_ADDR,
 151                                                     struct obj_section *,
 152                                                     struct block **,
 153                                                     struct symtab *);
 154
 155 extern struct call_site *call_site_for_pc (struct gdbarch *gdbarch,
 156                                            CORE_ADDR pc);
 157
 158 extern struct block *block_for_pc (CORE_ADDR);
 159
 160 extern struct block *block_for_pc_sect (CORE_ADDR, struct obj_section *);
 161
 162 extern const char *block_scope (const struct block *block);
 163
 164 extern void block_set_scope (struct block *block, const char *scope,
 165                              struct obstack *obstack);
 166
 167 extern struct using_direct *block_using (const struct block *block);
 168
 169 extern void block_set_using (struct block *block,
 170                              struct using_direct *using,
 171                              struct obstack *obstack);
 172
 173 extern const struct block *block_static_block (const struct block *block);
 174
 175 extern const struct block *block_global_block (const struct block *block);
 176
 177 extern struct block *allocate_block (struct obstack *obstack);
 178
 179 extern struct block *allocate_global_block (struct obstack *obstack);
 180
 181 extern void set_block_symtab (struct block *, struct symtab *);
 182
 183 /* A block iterator.  This structure should be treated as though it
 184    were opaque; it is only defined here because we want to support
 185    stack allocation of iterators.  */
 186
 187 struct block_iterator
 188 {
 189   /* If we're iterating over a single block, this holds the block.
 190      Otherwise, it holds the canonical symtab.  */
 191
 192   union
 193   {
 194     struct symtab *symtab;
 195     const struct block *block;
 196   } d;
 197
 198   /* If we're iterating over a single block, this is always -1.
 199      Otherwise, it holds the index of the current "included" symtab in
 200      the canonical symtab (that is, d.symtab->includes[idx]), with -1
 201      meaning the canonical symtab itself.  */
 202
 203   int idx;
 204
 205   /* Which block, either static or global, to iterate over.  If this
 206      is FIRST_LOCAL_BLOCK, then we are iterating over a single block.
 207      This is used to select which field of 'd' is in use.  */
 208
 209   enum block_enum which;
 210
 211   /* The underlying dictionary iterator.  */
 212
 213   struct dict_iterator dict_iter;
 214 };
 215
 216 /* Initialize ITERATOR to point at the first symbol in BLOCK, and
 217    return that first symbol, or NULL if BLOCK is empty.  */
 218
 219 extern struct symbol *block_iterator_first (const struct block *block,
 220                                             struct block_iterator *iterator);
 221
 222 /* Advance ITERATOR, and return the next symbol, or NULL if there are
 223    no more symbols.  Don't call this if you've previously received
 224    NULL from block_iterator_first or block_iterator_next on this
 225    iteration.  */
 226
 227 extern struct symbol *block_iterator_next (struct block_iterator *iterator);
 228
 229 /* Initialize ITERATOR to point at the first symbol in BLOCK whose
 230    SYMBOL_SEARCH_NAME is NAME (as tested using strcmp_iw), and return
 231    that first symbol, or NULL if there are no such symbols.  */
 232
 233 extern struct symbol *block_iter_name_first (const struct block *block,
 234                                              const char *name,
 235                                              struct block_iterator *iterator);
 236
 237 /* Advance ITERATOR to point at the next symbol in BLOCK whose
 238    SYMBOL_SEARCH_NAME is NAME (as tested using strcmp_iw), or NULL if
 239    there are no more such symbols.  Don't call this if you've
 240    previously received NULL from block_iterator_first or
 241    block_iterator_next on this iteration.  And don't call it unless
 242    ITERATOR was created by a previous call to block_iter_name_first
 243    with the same NAME.  */
 244
 245 extern struct symbol *block_iter_name_next (const char *name,
 246                                             struct block_iterator *iterator);
 247
 248 /* Initialize ITERATOR to point at the first symbol in BLOCK whose
 249    SYMBOL_SEARCH_NAME is NAME, as tested using COMPARE (which must use
 250    the same conventions as strcmp_iw and be compatible with any
 251    block hashing function), and return that first symbol, or NULL
 252    if there are no such symbols.  */
 253
 254 extern struct symbol *block_iter_match_first (const struct block *block,
 255                                               const char *name,
 256                                               symbol_compare_ftype *compare,
 257                                               struct block_iterator *iterator);
 258
 259 /* Advance ITERATOR to point at the next symbol in BLOCK whose
 260    SYMBOL_SEARCH_NAME is NAME, as tested using COMPARE (see
 261    block_iter_match_first), or NULL if there are no more such symbols.
 262    Don't call this if you've previously received NULL from
 263    block_iterator_match_first or block_iterator_match_next on this
 264    iteration.  And don't call it unless ITERATOR was created by a
 265    previous call to block_iter_match_first with the same NAME and COMPARE.  */
 266
 267 extern struct symbol *block_iter_match_next (const char *name,
 268                                              symbol_compare_ftype *compare,
 269                                              struct block_iterator *iterator);
 270
 271 /* Macro to loop through all symbols in a block BL, in no particular
 272    order.  ITER helps keep track of the iteration, and should be a
 273    struct block_iterator.  SYM points to the current symbol.  */
 274
 275 #define ALL_BLOCK_SYMBOLS(block, iter, sym)             \
 276   for ((sym) = block_iterator_first ((block), &(iter)); \
 277        (sym);                                           \
 278        (sym) = block_iterator_next (&(iter)))
 279
 280 #endif /* BLOCK_H */