gdb/block.h

   1 /* Code dealing with blocks for GDB.
   2
   3    Copyright (C) 2003, 2007 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 /* Opaque declarations.  */
  24
  25 struct symbol;
  26 struct symtab;
  27 struct block_namespace_info;
  28 struct using_direct;
  29 struct obstack;
  30 struct dictionary;
  31
  32 /* All of the name-scope contours of the program
  33    are represented by `struct block' objects.
  34    All of these objects are pointed to by the blockvector.
  35
  36    Each block represents one name scope.
  37    Each lexical context has its own block.
  38
  39    The blockvector begins with some special blocks.
  40    The GLOBAL_BLOCK contains all the symbols defined in this compilation
  41    whose scope is the entire program linked together.
  42    The STATIC_BLOCK contains all the symbols whose scope is the
  43    entire compilation excluding other separate compilations.
  44    Blocks starting with the FIRST_LOCAL_BLOCK are not special.
  45
  46    Each block records a range of core addresses for the code that
  47    is in the scope of the block.  The STATIC_BLOCK and GLOBAL_BLOCK
  48    give, for the range of code, the entire range of code produced
  49    by the compilation that the symbol segment belongs to.
  50
  51    The blocks appear in the blockvector
  52    in order of increasing starting-address,
  53    and, within that, in order of decreasing ending-address.
  54
  55    This implies that within the body of one function
  56    the blocks appear in the order of a depth-first tree walk.  */
  57
  58 struct block
  59 {
  60
  61   /* Addresses in the executable code that are in this block.  */
  62
  63   CORE_ADDR startaddr;
  64   CORE_ADDR endaddr;
  65
  66   /* The symbol that names this block, if the block is the body of a
  67      function; otherwise, zero.  */
  68
  69   struct symbol *function;
  70
  71   /* The `struct block' for the containing block, or 0 if none.
  72
  73      The superblock of a top-level local block (i.e. a function in the
  74      case of C) is the STATIC_BLOCK.  The superblock of the
  75      STATIC_BLOCK is the GLOBAL_BLOCK.  */
  76
  77   struct block *superblock;
  78
  79   /* This is used to store the symbols in the block.  */
  80
  81   struct dictionary *dict;
  82
  83   /* Used for language-specific info.  */
  84
  85   union
  86   {
  87     struct
  88     {
  89       /* Contains information about namespace-related info relevant to
  90          this block: using directives and the current namespace
  91          scope.  */
  92
  93       struct block_namespace_info *namespace;
  94     }
  95     cplus_specific;
  96   }
  97   language_specific;
  98
  99   /* Version of GCC used to compile the function corresponding
 100      to this block, or 0 if not compiled with GCC.  When possible,
 101      GCC should be compatible with the native compiler, or if that
 102      is not feasible, the differences should be fixed during symbol
 103      reading.  As of 16 Apr 93, this flag is never used to distinguish
 104      between gcc2 and the native compiler.
 105
 106      If there is no function corresponding to this block, this meaning
 107      of this flag is undefined.  */
 108
 109   unsigned char gcc_compile_flag;
 110 };
 111
 112 #define BLOCK_START(bl)         (bl)->startaddr
 113 #define BLOCK_END(bl)           (bl)->endaddr
 114 #define BLOCK_FUNCTION(bl)      (bl)->function
 115 #define BLOCK_SUPERBLOCK(bl)    (bl)->superblock
 116 #define BLOCK_GCC_COMPILED(bl)  (bl)->gcc_compile_flag
 117 #define BLOCK_DICT(bl)          (bl)->dict
 118 #define BLOCK_NAMESPACE(bl)   (bl)->language_specific.cplus_specific.namespace
 119
 120 /* Macro to loop through all symbols in a block BL, in no particular
 121    order.  ITER helps keep track of the iteration, and should be a
 122    struct dict_iterator.  SYM points to the current symbol.  */
 123
 124 #define ALL_BLOCK_SYMBOLS(block, iter, sym)                     \
 125         ALL_DICT_SYMBOLS (BLOCK_DICT (block), iter, sym)
 126
 127 struct blockvector
 128 {
 129   /* Number of blocks in the list.  */
 130   int nblocks;
 131   /* The blocks themselves.  */
 132   struct block *block[1];
 133 };
 134
 135 #define BLOCKVECTOR_NBLOCKS(blocklist) (blocklist)->nblocks
 136 #define BLOCKVECTOR_BLOCK(blocklist,n) (blocklist)->block[n]
 137
 138 /* Special block numbers */
 139
 140 enum { GLOBAL_BLOCK = 0, STATIC_BLOCK = 1, FIRST_LOCAL_BLOCK = 2 };
 141
 142 extern struct symbol *block_function (const struct block *);
 143
 144 extern int contained_in (const struct block *, const struct block *);
 145
 146 extern struct blockvector *blockvector_for_pc (CORE_ADDR, int *);
 147
 148 extern struct blockvector *blockvector_for_pc_sect (CORE_ADDR, asection *,
 149                                                     int *, struct symtab *);
 150
 151 extern struct block *block_for_pc (CORE_ADDR);
 152
 153 extern struct block *block_for_pc_sect (CORE_ADDR, asection *);
 154
 155 extern const char *block_scope (const struct block *block);
 156
 157 extern void block_set_scope (struct block *block, const char *scope,
 158                              struct obstack *obstack);
 159
 160 extern struct using_direct *block_using (const struct block *block);
 161
 162 extern void block_set_using (struct block *block,
 163                              struct using_direct *using,
 164                              struct obstack *obstack);
 165
 166 extern const struct block *block_static_block (const struct block *block);
 167
 168 extern const struct block *block_global_block (const struct block *block);
 169
 170 extern struct block *allocate_block (struct obstack *obstack);
 171
 172 #endif /* BLOCK_H */