xref: /dragonfly/contrib/gcc-4.7/gcc/ggc.h (revision ed36d35d)
1 /* Garbage collection for the GNU compiler.
2 
3    Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007,
4    2008, 2009, 2010, 2011 Free Software Foundation, Inc.
5 
6 This file is part of GCC.
7 
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
12 
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16 for more details.
17 
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3.  If not see
20 <http://www.gnu.org/licenses/>.  */
21 
22 #ifndef GCC_GGC_H
23 #define GCC_GGC_H
24 #include "statistics.h"
25 
26 /* Symbols are marked with `ggc' for `gcc gc' so as not to interfere with
27    an external gc library that might be linked in.  */
28 
29 /* Constants for general use.  */
30 extern const char empty_string[];	/* empty string */
31 
32 /* Internal functions and data structures used by the GTY
33    machinery, including the generated gt*.[hc] files.  */
34 
35 /* The first parameter is a pointer to a pointer, the second a cookie.  */
36 typedef void (*gt_pointer_operator) (void *, void *);
37 
38 #include "gtype-desc.h"
39 
40 /* One of these applies its third parameter (with cookie in the fourth
41    parameter) to each pointer in the object pointed to by the first
42    parameter, using the second parameter.  */
43 typedef void (*gt_note_pointers) (void *, void *, gt_pointer_operator,
44 				  void *);
45 
46 /* One of these is called before objects are re-ordered in memory.
47    The first parameter is the original object, the second is the
48    subobject that has had its pointers reordered, the third parameter
49    can compute the new values of a pointer when given the cookie in
50    the fourth parameter.  */
51 typedef void (*gt_handle_reorder) (void *, void *, gt_pointer_operator,
52 				   void *);
53 
54 /* Used by the gt_pch_n_* routines.  Register an object in the hash table.  */
55 extern int gt_pch_note_object (void *, void *, gt_note_pointers,
56 			       enum gt_types_enum);
57 
58 /* Used by the gt_pch_n_* routines.  Register that an object has a reorder
59    function.  */
60 extern void gt_pch_note_reorder (void *, void *, gt_handle_reorder);
61 
62 /* Mark the object in the first parameter and anything it points to.  */
63 typedef void (*gt_pointer_walker) (void *);
64 
65 /* Structures for the easy way to mark roots.
66    In an array, terminated by having base == NULL.  */
67 struct ggc_root_tab {
68   void *base;
69   size_t nelt;
70   size_t stride;
71   gt_pointer_walker cb;
72   gt_pointer_walker pchw;
73 };
74 #define LAST_GGC_ROOT_TAB { NULL, 0, 0, NULL, NULL }
75 /* Pointers to arrays of ggc_root_tab, terminated by NULL.  */
76 extern const struct ggc_root_tab * const gt_ggc_rtab[];
77 extern const struct ggc_root_tab * const gt_ggc_deletable_rtab[];
78 extern const struct ggc_root_tab * const gt_pch_cache_rtab[];
79 extern const struct ggc_root_tab * const gt_pch_scalar_rtab[];
80 
81 /* Structure for hash table cache marking.  */
82 struct htab;
83 struct ggc_cache_tab {
84   struct htab * *base;
85   size_t nelt;
86   size_t stride;
87   gt_pointer_walker cb;
88   gt_pointer_walker pchw;
89   int (*marked_p) (const void *);
90 };
91 #define LAST_GGC_CACHE_TAB { NULL, 0, 0, NULL, NULL, NULL }
92 /* Pointers to arrays of ggc_cache_tab, terminated by NULL.  */
93 extern const struct ggc_cache_tab * const gt_ggc_cache_rtab[];
94 
95 /* If EXPR is not NULL and previously unmarked, mark it and evaluate
96    to true.  Otherwise evaluate to false.  */
97 #define ggc_test_and_set_mark(EXPR) \
98   ((EXPR) != NULL && ((void *) (EXPR)) != (void *) 1 && ! ggc_set_mark (EXPR))
99 
100 #define ggc_mark(EXPR)				\
101   do {						\
102     const void *const a__ = (EXPR);		\
103     if (a__ != NULL && a__ != (void *) 1)	\
104       ggc_set_mark (a__);			\
105   } while (0)
106 
107 /* Actually set the mark on a particular region of memory, but don't
108    follow pointers.  This function is called by ggc_mark_*.  It
109    returns zero if the object was not previously marked; nonzero if
110    the object was already marked, or if, for any other reason,
111    pointers in this data structure should not be traversed.  */
112 extern int ggc_set_mark	(const void *);
113 
114 /* Return 1 if P has been marked, zero otherwise.
115    P must have been allocated by the GC allocator; it mustn't point to
116    static objects, stack variables, or memory allocated with malloc.  */
117 extern int ggc_marked_p	(const void *);
118 
119 /* PCH and GGC handling for strings, mostly trivial.  */
120 extern void gt_pch_n_S (const void *);
121 extern void gt_ggc_m_S (const void *);
122 
123 /* End of GTY machinery API.  */
124 
125 struct alloc_zone;
126 
127 /* Initialize the string pool.  */
128 extern void init_stringpool (void);
129 
130 /* Initialize the garbage collector.  */
131 extern void init_ggc (void);
132 
133 /* When true, identifier nodes are considered as GC roots.  When
134    false, identifier nodes are treated like any other GC-allocated
135    object, and the identifier hash table is treated as a weak
136    hash.  */
137 extern bool ggc_protect_identifiers;
138 
139 /* Write out all GCed objects to F.  */
140 extern void gt_pch_save (FILE *f);
141 
142 
143 /* Allocation.  */
144 
145 /* The internal primitive.  */
146 extern void *ggc_internal_alloc_stat (size_t MEM_STAT_DECL);
147 
148 extern size_t ggc_round_alloc_size (size_t requested_size);
149 
150 #define ggc_internal_alloc(s) ggc_internal_alloc_stat (s MEM_STAT_INFO)
151 
152 /* Allocate an object of the specified type and size.  */
153 extern void *ggc_alloc_typed_stat (enum gt_types_enum, size_t MEM_STAT_DECL);
154 
155 #define ggc_alloc_typed(s, z) ggc_alloc_typed_stat (s, z MEM_STAT_INFO)
156 
157 /* Allocates cleared memory.  */
158 extern void *ggc_internal_cleared_alloc_stat (size_t MEM_STAT_DECL);
159 
160 /* Resize a block.  */
161 extern void *ggc_realloc_stat (void *, size_t MEM_STAT_DECL);
162 
163 /* Free a block.  To be used when known for certain it's not reachable.  */
164 extern void ggc_free (void *);
165 
166 extern void ggc_record_overhead (size_t, size_t, void * MEM_STAT_DECL);
167 extern void ggc_free_overhead (void *);
168 extern void ggc_prune_overhead_list (void);
169 
170 extern void dump_ggc_loc_statistics (bool);
171 
172 /* Reallocators.  */
173 #define GGC_RESIZEVEC(T, P, N) \
174     ((T *) ggc_realloc_stat ((P), (N) * sizeof (T) MEM_STAT_INFO))
175 
176 #define GGC_RESIZEVAR(T, P, N)                          \
177     ((T *) ggc_realloc_stat ((P), (N) MEM_STAT_INFO))
178 
179 static inline void *
180 ggc_internal_vec_alloc_stat (size_t s, size_t c MEM_STAT_DECL)
181 {
182     return ggc_internal_alloc_stat (c * s PASS_MEM_STAT);
183 }
184 
185 static inline void *
186 ggc_internal_cleared_vec_alloc_stat (size_t s, size_t c MEM_STAT_DECL)
187 {
188     return ggc_internal_cleared_alloc_stat (c * s PASS_MEM_STAT);
189 }
190 
191 #define ggc_internal_cleared_vec_alloc(s, c) \
192     (ggc_internal_cleared_vec_alloc_stat ((s), (c) MEM_STAT_INFO))
193 
194 static inline void *
195 ggc_alloc_atomic_stat (size_t s MEM_STAT_DECL)
196 {
197     return ggc_internal_alloc_stat (s PASS_MEM_STAT);
198 }
199 
200 #define ggc_alloc_atomic(S)  (ggc_alloc_atomic_stat ((S) MEM_STAT_INFO))
201 
202 #define ggc_alloc_cleared_atomic(S)             \
203     (ggc_internal_cleared_alloc_stat ((S) MEM_STAT_INFO))
204 
205 extern void * ggc_cleared_alloc_htab_ignore_args (size_t, size_t);
206 
207 extern void * ggc_cleared_alloc_ptr_array_two_args (size_t, size_t);
208 
209 #define htab_create_ggc(SIZE, HASH, EQ, DEL) \
210   htab_create_typed_alloc (SIZE, HASH, EQ, DEL,	\
211 			   ggc_cleared_alloc_htab_ignore_args,		\
212 			   ggc_cleared_alloc_ptr_array_two_args,	\
213 			   ggc_free)
214 
215 #define splay_tree_new_ggc(COMPARE, ALLOC_TREE, ALLOC_NODE)		     \
216   splay_tree_new_typed_alloc (COMPARE, NULL, NULL, &ALLOC_TREE, &ALLOC_NODE, \
217 			      &ggc_splay_dont_free, NULL)
218 
219 extern void *ggc_splay_alloc (enum gt_types_enum, int, void *);
220 
221 extern void ggc_splay_dont_free (void *, void *);
222 
223 /* Allocate a gc-able string, and fill it with LENGTH bytes from CONTENTS.
224    If LENGTH is -1, then CONTENTS is assumed to be a
225    null-terminated string and the memory sized accordingly.  */
226 extern const char *ggc_alloc_string_stat (const char *contents, int length
227                                           MEM_STAT_DECL);
228 
229 #define ggc_alloc_string(c, l) ggc_alloc_string_stat (c, l MEM_STAT_INFO)
230 
231 /* Make a copy of S, in GC-able memory.  */
232 #define ggc_strdup(S) ggc_alloc_string_stat ((S), -1 MEM_STAT_INFO)
233 
234 /* Invoke the collector.  Garbage collection occurs only when this
235    function is called, not during allocations.  */
236 extern void ggc_collect	(void);
237 
238 /* Register an additional root table.  This can be useful for some
239    plugins.  Does nothing if the passed pointer is NULL. */
240 extern void ggc_register_root_tab (const struct ggc_root_tab *);
241 
242 /* Register an additional cache table.  This can be useful for some
243    plugins.  Does nothing if the passed pointer is NULL. */
244 extern void ggc_register_cache_tab (const struct ggc_cache_tab *);
245 
246 /* Read objects previously saved with gt_pch_save from F.  */
247 extern void gt_pch_restore (FILE *f);
248 
249 /* Statistics.  */
250 
251 /* Print allocation statistics.  */
252 extern void ggc_print_statistics (void);
253 
254 extern void stringpool_statistics (void);
255 
256 /* Heuristics.  */
257 extern void init_ggc_heuristics (void);
258 
259 /* Zone collection.  */
260 
261 /* For regular rtl allocations.  */
262 extern struct alloc_zone rtl_zone;
263 
264 /* For regular tree allocations.  */
265 extern struct alloc_zone tree_zone;
266 
267 /* For IDENTIFIER_NODE allocations.  */
268 extern struct alloc_zone tree_id_zone;
269 
270 #define ggc_alloc_rtvec_sized(NELT)                                     \
271   ggc_alloc_zone_rtvec_def (sizeof (struct rtvec_def)			\
272 			    + ((NELT) - 1) * sizeof (rtx),		\
273 			    &rtl_zone)
274 
275 #if defined (GGC_ZONE) && !defined (GENERATOR_FILE)
276 
277 /* Allocate an object into the specified allocation zone.  */
278 extern void *ggc_internal_alloc_zone_stat (size_t,
279 					  struct alloc_zone * MEM_STAT_DECL);
280 
281 extern void *ggc_internal_cleared_alloc_zone_stat (size_t,
282 					  struct alloc_zone * MEM_STAT_DECL);
283 
284 static inline void *
285 ggc_internal_zone_alloc_stat (struct alloc_zone * z, size_t s MEM_STAT_DECL)
286 {
287     return ggc_internal_alloc_zone_stat (s, z PASS_MEM_STAT);
288 }
289 
290 static inline void *
291 ggc_internal_zone_cleared_alloc_stat (struct alloc_zone * z, size_t s
292                                       MEM_STAT_DECL)
293 {
294     return ggc_internal_cleared_alloc_zone_stat (s, z PASS_MEM_STAT);
295 }
296 
297 static inline void *
298 ggc_internal_zone_vec_alloc_stat (struct alloc_zone * z, size_t s, size_t n
299                                   MEM_STAT_DECL)
300 {
301     return ggc_internal_alloc_zone_stat (s * n, z PASS_MEM_STAT);
302 }
303 
304 
305 #else
306 
307 static inline void *
308 ggc_internal_zone_alloc_stat (struct alloc_zone * z ATTRIBUTE_UNUSED,
309                               size_t s MEM_STAT_DECL)
310 {
311     return ggc_internal_alloc_stat (s PASS_MEM_STAT);
312 }
313 
314 static inline void *
315 ggc_internal_zone_cleared_alloc_stat (struct alloc_zone * z ATTRIBUTE_UNUSED,
316                                       size_t s MEM_STAT_DECL)
317 {
318     return ggc_internal_cleared_alloc_stat (s PASS_MEM_STAT);
319 }
320 
321 static inline void *
322 ggc_internal_zone_vec_alloc_stat (struct alloc_zone * z ATTRIBUTE_UNUSED,
323                                   size_t s, size_t n MEM_STAT_DECL)
324 {
325     return ggc_internal_vec_alloc_stat (s, n PASS_MEM_STAT);
326 }
327 
328 #endif
329 
330 /* Memory statistics passing versions of some allocators.  Too few of them to
331    make gengtype produce them, so just define the needed ones here.  */
332 static inline struct rtx_def *
333 ggc_alloc_zone_rtx_def_stat (struct alloc_zone * z, size_t s MEM_STAT_DECL)
334 {
335   return (struct rtx_def *) ggc_internal_zone_alloc_stat (z, s PASS_MEM_STAT);
336 }
337 
338 static inline union tree_node *
339 ggc_alloc_zone_tree_node_stat (struct alloc_zone * z, size_t s MEM_STAT_DECL)
340 {
341   return (union tree_node *) ggc_internal_zone_alloc_stat (z, s PASS_MEM_STAT);
342 }
343 
344 static inline union tree_node *
345 ggc_alloc_zone_cleared_tree_node_stat (struct alloc_zone * z, size_t s
346                                        MEM_STAT_DECL)
347 {
348   return (union tree_node *)
349     ggc_internal_zone_cleared_alloc_stat (z, s PASS_MEM_STAT);
350 }
351 
352 static inline union gimple_statement_d *
353 ggc_alloc_cleared_gimple_statement_d_stat (size_t s MEM_STAT_DECL)
354 {
355   return (union gimple_statement_d *)
356     ggc_internal_cleared_alloc_stat (s PASS_MEM_STAT);
357 }
358 
359 #endif
360