2013-02-25 Tom de Vries <tom@codesourcery.com>
[official-gcc.git] / gcc / ggc.h
blobb31bc80489f2a50aed4b110d4c7035805000b924
1 /* Garbage collection for the GNU compiler.
3 Copyright (C) 1998-2013 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 #ifndef GCC_GGC_H
22 #define GCC_GGC_H
23 #include "statistics.h"
25 /* Symbols are marked with `ggc' for `gcc gc' so as not to interfere with
26 an external gc library that might be linked in. */
28 /* Constants for general use. */
29 extern const char empty_string[]; /* empty string */
31 /* Internal functions and data structures used by the GTY
32 machinery, including the generated gt*.[hc] files. */
34 #include "gtype-desc.h"
36 /* One of these applies its third parameter (with cookie in the fourth
37 parameter) to each pointer in the object pointed to by the first
38 parameter, using the second parameter. */
39 typedef void (*gt_note_pointers) (void *, void *, gt_pointer_operator,
40 void *);
42 /* One of these is called before objects are re-ordered in memory.
43 The first parameter is the original object, the second is the
44 subobject that has had its pointers reordered, the third parameter
45 can compute the new values of a pointer when given the cookie in
46 the fourth parameter. */
47 typedef void (*gt_handle_reorder) (void *, void *, gt_pointer_operator,
48 void *);
50 /* Used by the gt_pch_n_* routines. Register an object in the hash table. */
51 extern int gt_pch_note_object (void *, void *, gt_note_pointers);
53 /* Used by the gt_pch_n_* routines. Register that an object has a reorder
54 function. */
55 extern void gt_pch_note_reorder (void *, void *, gt_handle_reorder);
57 /* Mark the object in the first parameter and anything it points to. */
58 typedef void (*gt_pointer_walker) (void *);
60 /* Structures for the easy way to mark roots.
61 In an array, terminated by having base == NULL. */
62 struct ggc_root_tab {
63 void *base;
64 size_t nelt;
65 size_t stride;
66 gt_pointer_walker cb;
67 gt_pointer_walker pchw;
69 #define LAST_GGC_ROOT_TAB { NULL, 0, 0, NULL, NULL }
70 /* Pointers to arrays of ggc_root_tab, terminated by NULL. */
71 extern const struct ggc_root_tab * const gt_ggc_rtab[];
72 extern const struct ggc_root_tab * const gt_ggc_deletable_rtab[];
73 extern const struct ggc_root_tab * const gt_pch_cache_rtab[];
74 extern const struct ggc_root_tab * const gt_pch_scalar_rtab[];
76 /* Structure for hash table cache marking. */
77 struct htab;
78 struct ggc_cache_tab {
79 struct htab * *base;
80 size_t nelt;
81 size_t stride;
82 gt_pointer_walker cb;
83 gt_pointer_walker pchw;
84 int (*marked_p) (const void *);
86 #define LAST_GGC_CACHE_TAB { NULL, 0, 0, NULL, NULL, NULL }
87 /* Pointers to arrays of ggc_cache_tab, terminated by NULL. */
88 extern const struct ggc_cache_tab * const gt_ggc_cache_rtab[];
90 /* If EXPR is not NULL and previously unmarked, mark it and evaluate
91 to true. Otherwise evaluate to false. */
92 #define ggc_test_and_set_mark(EXPR) \
93 ((EXPR) != NULL && ((void *) (EXPR)) != (void *) 1 && ! ggc_set_mark (EXPR))
95 #define ggc_mark(EXPR) \
96 do { \
97 const void *const a__ = (EXPR); \
98 if (a__ != NULL && a__ != (void *) 1) \
99 ggc_set_mark (a__); \
100 } while (0)
102 /* Actually set the mark on a particular region of memory, but don't
103 follow pointers. This function is called by ggc_mark_*. It
104 returns zero if the object was not previously marked; nonzero if
105 the object was already marked, or if, for any other reason,
106 pointers in this data structure should not be traversed. */
107 extern int ggc_set_mark (const void *);
109 /* Return 1 if P has been marked, zero otherwise.
110 P must have been allocated by the GC allocator; it mustn't point to
111 static objects, stack variables, or memory allocated with malloc. */
112 extern int ggc_marked_p (const void *);
114 /* PCH and GGC handling for strings, mostly trivial. */
115 extern void gt_pch_n_S (const void *);
116 extern void gt_ggc_m_S (const void *);
118 /* End of GTY machinery API. */
120 /* Initialize the string pool. */
121 extern void init_stringpool (void);
123 /* Initialize the garbage collector. */
124 extern void init_ggc (void);
126 /* When true, identifier nodes are considered as GC roots. When
127 false, identifier nodes are treated like any other GC-allocated
128 object, and the identifier hash table is treated as a weak
129 hash. */
130 extern bool ggc_protect_identifiers;
132 /* Write out all GCed objects to F. */
133 extern void gt_pch_save (FILE *f);
136 /* Allocation. */
138 /* The internal primitive. */
139 extern void *ggc_internal_alloc_stat (size_t MEM_STAT_DECL)
140 ATTRIBUTE_MALLOC;
142 extern size_t ggc_round_alloc_size (size_t requested_size);
144 #define ggc_internal_alloc(s) ggc_internal_alloc_stat (s MEM_STAT_INFO)
146 /* Allocates cleared memory. */
147 extern void *ggc_internal_cleared_alloc_stat (size_t MEM_STAT_DECL)
148 ATTRIBUTE_MALLOC;
150 /* Resize a block. */
151 extern void *ggc_realloc_stat (void *, size_t MEM_STAT_DECL);
153 /* Free a block. To be used when known for certain it's not reachable. */
154 extern void ggc_free (void *);
156 extern void dump_ggc_loc_statistics (bool);
158 /* Reallocators. */
159 #define GGC_RESIZEVEC(T, P, N) \
160 ((T *) ggc_realloc_stat ((P), (N) * sizeof (T) MEM_STAT_INFO))
162 #define GGC_RESIZEVAR(T, P, N) \
163 ((T *) ggc_realloc_stat ((P), (N) MEM_STAT_INFO))
165 static inline void *
166 ggc_internal_vec_alloc_stat (size_t s, size_t c MEM_STAT_DECL)
168 return ggc_internal_alloc_stat (c * s PASS_MEM_STAT);
171 static inline void *
172 ggc_internal_cleared_vec_alloc_stat (size_t s, size_t c MEM_STAT_DECL)
174 return ggc_internal_cleared_alloc_stat (c * s PASS_MEM_STAT);
177 #define ggc_internal_cleared_vec_alloc(s, c) \
178 (ggc_internal_cleared_vec_alloc_stat ((s), (c) MEM_STAT_INFO))
180 static inline void *
181 ggc_alloc_atomic_stat (size_t s MEM_STAT_DECL)
183 return ggc_internal_alloc_stat (s PASS_MEM_STAT);
186 #define ggc_alloc_atomic(S) (ggc_alloc_atomic_stat ((S) MEM_STAT_INFO))
188 #define ggc_alloc_cleared_atomic(S) \
189 (ggc_internal_cleared_alloc_stat ((S) MEM_STAT_INFO))
191 extern void *ggc_cleared_alloc_htab_ignore_args (size_t, size_t)
192 ATTRIBUTE_MALLOC;
194 extern void *ggc_cleared_alloc_ptr_array_two_args (size_t, size_t)
195 ATTRIBUTE_MALLOC;
197 #define htab_create_ggc(SIZE, HASH, EQ, DEL) \
198 htab_create_typed_alloc (SIZE, HASH, EQ, DEL, \
199 ggc_cleared_alloc_htab_ignore_args, \
200 ggc_cleared_alloc_ptr_array_two_args, \
201 ggc_free)
203 #define splay_tree_new_ggc(COMPARE, ALLOC_TREE, ALLOC_NODE) \
204 splay_tree_new_typed_alloc (COMPARE, NULL, NULL, &ALLOC_TREE, &ALLOC_NODE, \
205 &ggc_splay_dont_free, NULL)
207 extern void *ggc_splay_alloc (int, void *)
208 ATTRIBUTE_MALLOC;
210 extern void ggc_splay_dont_free (void *, void *);
212 /* Allocate a gc-able string, and fill it with LENGTH bytes from CONTENTS.
213 If LENGTH is -1, then CONTENTS is assumed to be a
214 null-terminated string and the memory sized accordingly. */
215 extern const char *ggc_alloc_string_stat (const char *contents, int length
216 MEM_STAT_DECL);
218 #define ggc_alloc_string(c, l) ggc_alloc_string_stat (c, l MEM_STAT_INFO)
220 /* Make a copy of S, in GC-able memory. */
221 #define ggc_strdup(S) ggc_alloc_string_stat ((S), -1 MEM_STAT_INFO)
223 /* Invoke the collector. Garbage collection occurs only when this
224 function is called, not during allocations. */
225 extern void ggc_collect (void);
227 /* Register an additional root table. This can be useful for some
228 plugins. Does nothing if the passed pointer is NULL. */
229 extern void ggc_register_root_tab (const struct ggc_root_tab *);
231 /* Register an additional cache table. This can be useful for some
232 plugins. Does nothing if the passed pointer is NULL. */
233 extern void ggc_register_cache_tab (const struct ggc_cache_tab *);
235 /* Read objects previously saved with gt_pch_save from F. */
236 extern void gt_pch_restore (FILE *f);
238 /* Statistics. */
240 /* Print allocation statistics. */
241 extern void ggc_print_statistics (void);
243 extern void stringpool_statistics (void);
245 /* Heuristics. */
246 extern void init_ggc_heuristics (void);
248 #define ggc_alloc_rtvec_sized(NELT) \
249 ggc_alloc_rtvec_def (sizeof (struct rtvec_def) \
250 + ((NELT) - 1) * sizeof (rtx)) \
252 /* Memory statistics passing versions of some allocators. Too few of them to
253 make gengtype produce them, so just define the needed ones here. */
254 static inline struct rtx_def *
255 ggc_alloc_rtx_def_stat (size_t s MEM_STAT_DECL)
257 return (struct rtx_def *) ggc_internal_alloc_stat (s PASS_MEM_STAT);
260 static inline union tree_node *
261 ggc_alloc_tree_node_stat (size_t s MEM_STAT_DECL)
263 return (union tree_node *) ggc_internal_alloc_stat (s PASS_MEM_STAT);
266 static inline union tree_node *
267 ggc_alloc_cleared_tree_node_stat (size_t s MEM_STAT_DECL)
269 return (union tree_node *) ggc_internal_cleared_alloc_stat (s PASS_MEM_STAT);
272 static inline union gimple_statement_d *
273 ggc_alloc_cleared_gimple_statement_d_stat (size_t s MEM_STAT_DECL)
275 return (union gimple_statement_d *)
276 ggc_internal_cleared_alloc_stat (s PASS_MEM_STAT);
279 #endif