Daily bump.
[official-gcc.git] / gcc / ggc.h
blobae021fc203afea2382972c7794629ff998c00ce9
1 /* Garbage collection for the GNU compiler.
2 Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 2, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING. If not, write to the Free
18 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
19 02111-1307, USA. */
21 #include "varray.h"
23 /* Symbols are marked with `ggc' for `gcc gc' so as not to interfere with
24 an external gc library that might be linked in. */
26 /* These structures are defined in various headers throughout the
27 compiler. However, rather than force everyone who includes this
28 header to include all the headers in which they are declared, we
29 just forward-declare them here. */
30 struct eh_status;
31 struct emit_status;
32 struct expr_status;
33 struct hash_table;
34 struct label_node;
35 struct rtx_def;
36 struct rtvec_def;
37 struct stmt_status;
38 union tree_node;
39 struct varasm_status;
41 /* Constants for general use. */
42 extern const char empty_string[]; /* empty string */
43 extern const char digit_vector[]; /* "0" .. "9" */
44 #define digit_string(d) (digit_vector + ((d) * 2))
46 /* Trees that have been marked, but whose children still need marking. */
47 extern varray_type ggc_pending_trees;
49 /* Manipulate global roots that are needed between calls to gc. */
50 extern void ggc_add_root PARAMS ((void *base, int nelt,
51 int size, void (*)(void *)));
52 extern void ggc_add_rtx_root PARAMS ((struct rtx_def **, int nelt));
53 extern void ggc_add_tree_root PARAMS ((union tree_node **,
54 int nelt));
55 extern void ggc_add_rtx_varray_root PARAMS ((struct varray_head_tag **,
56 int nelt));
57 extern void ggc_add_tree_varray_root PARAMS ((struct varray_head_tag **,
58 int nelt));
59 extern void ggc_add_tree_hash_table_root PARAMS ((struct hash_table **,
60 int nelt));
61 extern void ggc_del_root PARAMS ((void *base));
63 /* Types used for mark test and marking functions, if specified, in call
64 below. */
65 typedef int (*ggc_htab_marked_p) PARAMS ((const void *));
66 typedef void (*ggc_htab_mark) PARAMS ((const void *));
68 /* Add a hash table to be scanned when all roots have been processed. We
69 delete any entry in the table that has not been marked. The argument is
70 really htab_t. */
71 extern void ggc_add_deletable_htab PARAMS ((PTR, ggc_htab_marked_p,
72 ggc_htab_mark));
74 /* Mark nodes from the gc_add_root callback. These functions follow
75 pointers to mark other objects too. */
76 extern void ggc_mark_rtx_varray PARAMS ((struct varray_head_tag *));
77 extern void ggc_mark_tree_varray PARAMS ((struct varray_head_tag *));
78 extern void ggc_mark_tree_hash_table PARAMS ((struct hash_table *));
79 extern void ggc_mark_roots PARAMS ((void));
81 extern void ggc_mark_rtx_children PARAMS ((struct rtx_def *));
82 extern void ggc_mark_rtvec_children PARAMS ((struct rtvec_def *));
84 /* If EXPR is not NULL and previously unmarked, mark it and evaluate
85 to true. Otherwise evaluate to false. */
86 #define ggc_test_and_set_mark(EXPR) \
87 ((EXPR) != NULL && ! ggc_set_mark (EXPR))
89 #define ggc_mark_rtx(EXPR) \
90 do { \
91 rtx r__ = (EXPR); \
92 if (ggc_test_and_set_mark (r__)) \
93 ggc_mark_rtx_children (r__); \
94 } while (0)
96 #define ggc_mark_tree(EXPR) \
97 do { \
98 tree t__ = (EXPR); \
99 if (ggc_test_and_set_mark (t__)) \
100 VARRAY_PUSH_TREE (ggc_pending_trees, t__); \
101 } while (0)
103 #define ggc_mark_nonnull_tree(EXPR) \
104 do { \
105 tree t__ = (EXPR); \
106 if (! ggc_set_mark (t__)) \
107 VARRAY_PUSH_TREE (ggc_pending_trees, t__); \
108 } while (0)
110 #define ggc_mark_rtvec(EXPR) \
111 do { \
112 rtvec v__ = (EXPR); \
113 if (ggc_test_and_set_mark (v__)) \
114 ggc_mark_rtvec_children (v__); \
115 } while (0)
117 #define ggc_mark(EXPR) \
118 do { \
119 const void *a__ = (EXPR); \
120 if (a__ != NULL) \
121 ggc_set_mark (a__); \
122 } while (0)
124 /* A GC implementation must provide these functions. */
126 /* Initialize the garbage collector. */
127 extern void init_ggc PARAMS ((void));
128 extern void init_stringpool PARAMS ((void));
130 /* Start a new GGC context. Memory allocated in previous contexts
131 will not be collected while the new context is active. */
132 extern void ggc_push_context PARAMS ((void));
134 /* Finish a GC context. Any uncollected memory in the new context
135 will be merged with the old context. */
136 extern void ggc_pop_context PARAMS ((void));
138 /* Allocation. */
140 /* The internal primitive. */
141 extern void *ggc_alloc PARAMS ((size_t));
142 /* Like ggc_alloc, but allocates cleared memory. */
143 extern void *ggc_alloc_cleared PARAMS ((size_t));
145 #define ggc_alloc_rtx(NSLOTS) \
146 ((struct rtx_def *) ggc_alloc (sizeof (struct rtx_def) \
147 + ((NSLOTS) - 1) * sizeof (rtunion)))
149 #define ggc_alloc_rtvec(NELT) \
150 ((struct rtvec_def *) ggc_alloc (sizeof (struct rtvec_def) \
151 + ((NELT) - 1) * sizeof (rtx)))
153 #define ggc_alloc_tree(LENGTH) ((union tree_node *) ggc_alloc (LENGTH))
155 /* Allocate a gc-able string, and fill it with LENGTH bytes from CONTENTS.
156 If LENGTH is -1, then CONTENTS is assumed to be a
157 null-terminated string and the memory sized accordingly. */
158 extern const char *ggc_alloc_string PARAMS ((const char *contents,
159 int length));
161 /* Make a copy of S, in GC-able memory. */
162 #define ggc_strdup(S) ggc_alloc_string((S), -1)
164 /* Invoke the collector. Garbage collection occurs only when this
165 function is called, not during allocations. */
166 extern void ggc_collect PARAMS ((void));
168 /* Actually set the mark on a particular region of memory, but don't
169 follow pointers. This function is called by ggc_mark_*. It
170 returns zero if the object was not previously marked; non-zero if
171 the object was already marked, or if, for any other reason,
172 pointers in this data structure should not be traversed. */
173 extern int ggc_set_mark PARAMS ((const void *));
175 /* Return 1 if P has been marked, zero otherwise.
176 P must have been allocated by the GC allocator; it mustn't point to
177 static objects, stack variables, or memory allocated with malloc. */
178 extern int ggc_marked_p PARAMS ((const void *));
180 /* Callbacks to the languages. */
182 /* This is the language's opportunity to mark nodes held through
183 the lang_specific hooks in the tree. */
184 extern void lang_mark_tree PARAMS ((union tree_node *));
186 /* The FALSE_LABEL_STACK, declared in except.h, has language-dependent
187 semantics. If a front-end needs to mark the false label stack, it
188 should set this pointer to a non-NULL value. Otherwise, no marking
189 will be done. */
190 extern void (*lang_mark_false_label_stack) PARAMS ((struct label_node *));
192 /* Mark functions for various structs scattered about. */
194 void mark_eh_status PARAMS ((struct eh_status *));
195 void mark_emit_status PARAMS ((struct emit_status *));
196 void mark_expr_status PARAMS ((struct expr_status *));
197 void mark_stmt_status PARAMS ((struct stmt_status *));
198 void mark_varasm_status PARAMS ((struct varasm_status *));
199 void mark_optab PARAMS ((void *));
201 /* Statistics. */
203 /* This structure contains the statistics common to all collectors.
204 Particular collectors can extend this structure. */
205 typedef struct ggc_statistics
207 /* The Ith element is the number of nodes allocated with code I. */
208 unsigned num_trees[256];
209 /* The Ith element is the number of bytes allocated by nodes with
210 code I. */
211 size_t size_trees[256];
212 /* The Ith element is the number of nodes allocated with code I. */
213 unsigned num_rtxs[256];
214 /* The Ith element is the number of bytes allocated by nodes with
215 code I. */
216 size_t size_rtxs[256];
217 /* The total size of the tree nodes allocated. */
218 size_t total_size_trees;
219 /* The total size of the RTL nodes allocated. */
220 size_t total_size_rtxs;
221 /* The total number of tree nodes allocated. */
222 unsigned total_num_trees;
223 /* The total number of RTL nodes allocated. */
224 unsigned total_num_rtxs;
225 } ggc_statistics;
227 /* Return the number of bytes allocated at the indicated address. */
228 extern size_t ggc_get_size PARAMS ((const void *));
230 /* Used by the various collectors to gather and print statistics that
231 do not depend on the collector in use. */
232 extern void ggc_print_common_statistics PARAMS ((FILE *, ggc_statistics *));
234 /* Print allocation statistics. */
235 extern void ggc_print_statistics PARAMS ((void));
236 extern void stringpool_statistics PARAMS ((void));