1/* Code dealing with blocks for GDB.
2
3   Copyright 2003 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 2 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, write to the Free Software
19   Foundation, Inc., 59 Temple Place - Suite 330,
20   Boston, MA 02111-1307, USA.  */
21
22#ifndef BLOCK_H
23#define BLOCK_H
24
25/* Opaque declarations.  */
26
27struct symbol;
28struct symtab;
29struct block_namespace_info;
30struct using_direct;
31struct obstack;
32struct dictionary;
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
60struct 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; 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  /* Version of GCC used to compile the function corresponding
102     to this block, or 0 if not compiled with GCC.  When possible,
103     GCC should be compatible with the native compiler, or if that
104     is not feasible, the differences should be fixed during symbol
105     reading.  As of 16 Apr 93, this flag is never used to distinguish
106     between gcc2 and the native compiler.
107
108     If there is no function corresponding to this block, this meaning
109     of this flag is undefined.  */
110
111  unsigned char gcc_compile_flag;
112};
113
114#define BLOCK_START(bl)		(bl)->startaddr
115#define BLOCK_END(bl)		(bl)->endaddr
116#define BLOCK_FUNCTION(bl)	(bl)->function
117#define BLOCK_SUPERBLOCK(bl)	(bl)->superblock
118#define BLOCK_GCC_COMPILED(bl)	(bl)->gcc_compile_flag
119#define BLOCK_DICT(bl)		(bl)->dict
120#define BLOCK_NAMESPACE(bl)   (bl)->language_specific.cplus_specific.namespace
121
122/* Macro to loop through all symbols in a block BL, in no particular
123   order.  ITER helps keep track of the iteration, and should be a
124   struct dict_iterator.  SYM points to the current symbol.  */
125
126#define ALL_BLOCK_SYMBOLS(block, iter, sym)			\
127	ALL_DICT_SYMBOLS (BLOCK_DICT (block), iter, sym)
128
129struct blockvector
130{
131  /* Number of blocks in the list.  */
132  int nblocks;
133  /* The blocks themselves.  */
134  struct block *block[1];
135};
136
137#define BLOCKVECTOR_NBLOCKS(blocklist) (blocklist)->nblocks
138#define BLOCKVECTOR_BLOCK(blocklist,n) (blocklist)->block[n]
139
140/* Special block numbers */
141
142enum { GLOBAL_BLOCK = 0, STATIC_BLOCK = 1, FIRST_LOCAL_BLOCK = 2 };
143
144extern struct symbol *block_function (const struct block *);
145
146extern int contained_in (const struct block *, const struct block *);
147
148extern struct blockvector *blockvector_for_pc (CORE_ADDR, int *);
149
150extern struct blockvector *blockvector_for_pc_sect (CORE_ADDR, asection *,
151						    int *, struct symtab *);
152
153extern struct block *block_for_pc (CORE_ADDR);
154
155extern struct block *block_for_pc_sect (CORE_ADDR, asection *);
156
157extern const char *block_scope (const struct block *block);
158
159extern void block_set_scope (struct block *block, const char *scope,
160			     struct obstack *obstack);
161
162extern struct using_direct *block_using (const struct block *block);
163
164extern void block_set_using (struct block *block,
165			     struct using_direct *using,
166			     struct obstack *obstack);
167
168extern const struct block *block_static_block (const struct block *block);
169
170extern const struct block *block_global_block (const struct block *block);
171
172extern struct block *allocate_block (struct obstack *obstack);
173
174#endif /* BLOCK_H */
175