Line data Source code
1 : /* Garbage collection for the GNU compiler.
2 :
3 : Copyright (C) 1998-2023 Free Software Foundation, Inc.
4 :
5 : This file is part of GCC.
6 :
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.
11 :
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.
16 :
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/>. */
20 :
21 : #ifndef GCC_GGC_H
22 : #define GCC_GGC_H
23 :
24 : /* Symbols are marked with `ggc' for `gcc gc' so as not to interfere with
25 : an external gc library that might be linked in. */
26 :
27 : /* Internal functions and data structures used by the GTY
28 : machinery, including the generated gt*.[hc] files. */
29 :
30 : #include "gtype-desc.h"
31 :
32 : /* One of these applies its third parameter (with cookie in the fourth
33 : parameter) to each pointer in the object pointed to by the first
34 : parameter, using the second parameter. */
35 : typedef void (*gt_note_pointers) (void *, void *, gt_pointer_operator,
36 : void *);
37 :
38 : /* One of these is called before objects are re-ordered in memory.
39 : The first parameter is the original object, the second is the
40 : subobject that has had its pointers reordered, the third parameter
41 : can compute the new values of a pointer when given the cookie in
42 : the fourth parameter. */
43 : typedef void (*gt_handle_reorder) (void *, void *, gt_pointer_operator,
44 : void *);
45 :
46 : /* Used by the gt_pch_n_* routines. Register an object in the hash table. */
47 : extern int gt_pch_note_object (void *, void *, gt_note_pointers,
48 : size_t length_override = (size_t)-1);
49 :
50 : /* Used by the gt_pch_p_* routines. Register address of a callback
51 : pointer. */
52 : extern void gt_pch_note_callback (void *, void *);
53 :
54 : /* Used by the gt_pch_n_* routines. Register that an object has a reorder
55 : function. */
56 : extern void gt_pch_note_reorder (void *, void *, gt_handle_reorder);
57 :
58 : /* generated function to clear caches in gc memory. */
59 : extern void gt_clear_caches ();
60 :
61 : /* Mark the object in the first parameter and anything it points to. */
62 : typedef void (*gt_pointer_walker) (void *);
63 :
64 : /* Structures for the easy way to mark roots.
65 : In an array, terminated by having base == NULL. */
66 : struct ggc_root_tab {
67 : void *base;
68 : size_t nelt;
69 : size_t stride;
70 : gt_pointer_walker cb;
71 : gt_pointer_walker pchw;
72 : };
73 : #define LAST_GGC_ROOT_TAB { NULL, 0, 0, NULL, NULL }
74 : /* Pointers to arrays of ggc_root_tab, terminated by NULL. */
75 : extern const struct ggc_root_tab * const gt_ggc_rtab[];
76 : extern const struct ggc_root_tab * const gt_ggc_deletable_rtab[];
77 : extern const struct ggc_root_tab * const gt_pch_scalar_rtab[];
78 :
79 : /* If EXPR is not NULL and previously unmarked, mark it and evaluate
80 : to true. Otherwise evaluate to false. */
81 : #define ggc_test_and_set_mark(EXPR) \
82 : ((EXPR) != NULL && ((void *) (EXPR)) != (void *) 1 && ! ggc_set_mark (EXPR))
83 :
84 : #define ggc_mark(EXPR) \
85 : do { \
86 : const void *const a__ = (EXPR); \
87 : if (a__ != NULL && a__ != (void *) 1) \
88 : ggc_set_mark (a__); \
89 : } while (0)
90 :
91 : /* Actually set the mark on a particular region of memory, but don't
92 : follow pointers. This function is called by ggc_mark_*. It
93 : returns false if the object was not previously marked; true if
94 : the object was already marked, or if, for any other reason,
95 : pointers in this data structure should not be traversed. */
96 : extern bool ggc_set_mark (const void *);
97 :
98 : /* Return true if P has been marked, zero otherwise.
99 : P must have been allocated by the GC allocator; it mustn't point to
100 : static objects, stack variables, or memory allocated with malloc. */
101 : extern bool ggc_marked_p (const void *);
102 :
103 : /* PCH and GGC handling for strings, mostly trivial. */
104 : extern void gt_pch_n_S (const void *);
105 : extern void gt_pch_n_S2 (const void *, size_t);
106 : extern void gt_ggc_m_S (const void *);
107 :
108 : /* End of GTY machinery API. */
109 :
110 : /* Initialize the string pool. */
111 : extern void init_stringpool (void);
112 :
113 : /* Initialize the garbage collector. */
114 : extern void init_ggc (void);
115 :
116 : /* When true, identifier nodes are considered as GC roots. When
117 : false, identifier nodes are treated like any other GC-allocated
118 : object, and the identifier hash table is treated as a weak
119 : hash. */
120 : extern bool ggc_protect_identifiers;
121 :
122 : /* Write out all GCed objects to F. */
123 : extern void gt_pch_save (FILE *f);
124 :
125 :
126 : /* Allocation. */
127 :
128 : /* The internal primitive. */
129 : extern void *ggc_internal_alloc (size_t, void (*)(void *), size_t,
130 : size_t CXX_MEM_STAT_INFO)
131 : ATTRIBUTE_MALLOC;
132 :
133 : inline void *
134 351366909 : ggc_internal_alloc (size_t s CXX_MEM_STAT_INFO)
135 : {
136 351366909 : return ggc_internal_alloc (s, NULL, 0, 1 PASS_MEM_STAT);
137 : }
138 :
139 : extern size_t ggc_round_alloc_size (size_t requested_size);
140 :
141 : /* Allocates cleared memory. */
142 : extern void *ggc_internal_cleared_alloc (size_t, void (*)(void *),
143 : size_t, size_t
144 : CXX_MEM_STAT_INFO) ATTRIBUTE_MALLOC;
145 :
146 : inline void *
147 766511419 : ggc_internal_cleared_alloc (size_t s CXX_MEM_STAT_INFO)
148 : {
149 766511419 : return ggc_internal_cleared_alloc (s, NULL, 0, 1 PASS_MEM_STAT);
150 : }
151 :
152 : /* Resize a block. */
153 : extern void *ggc_realloc (void *, size_t CXX_MEM_STAT_INFO);
154 :
155 : /* Free a block. To be used when known for certain it's not reachable. */
156 : extern void ggc_free (void *);
157 :
158 : extern void dump_ggc_loc_statistics ();
159 :
160 : /* Reallocator. */
161 : #define GGC_RESIZEVEC(T, P, N) \
162 : ((T *) ggc_realloc ((P), (N) * sizeof (T) MEM_STAT_INFO))
163 :
164 : template<typename T>
165 : void
166 1124446 : finalize (void *p)
167 : {
168 1124446 : static_cast<T *> (p)->~T ();
169 1124446 : }
170 :
171 : template<typename T>
172 : inline bool
173 : need_finalization_p ()
174 : {
175 : #if GCC_VERSION >= 4003
176 : return !__has_trivial_destructor (T);
177 : #else
178 : return true;
179 : #endif
180 : }
181 :
182 : template<typename T>
183 : inline T *
184 284686636 : ggc_alloc (ALONE_CXX_MEM_STAT_INFO)
185 : {
186 : if (need_finalization_p<T> ())
187 1852193 : return static_cast<T *> (ggc_internal_alloc (sizeof (T), finalize<T>, 0, 1
188 : PASS_MEM_STAT));
189 : else
190 282834443 : return static_cast<T *> (ggc_internal_alloc (sizeof (T), NULL, 0, 1
191 : PASS_MEM_STAT));
192 : }
193 :
194 : /* GGC allocation function that does not call finalizer for type
195 : that have need_finalization_p equal to true. User is responsible
196 : for calling of the destructor. */
197 :
198 : template<typename T>
199 : inline T *
200 : ggc_alloc_no_dtor (ALONE_CXX_MEM_STAT_INFO)
201 : {
202 : return static_cast<T *> (ggc_internal_alloc (sizeof (T), NULL, 0, 1
203 : PASS_MEM_STAT));
204 : }
205 :
206 : template<typename T>
207 : inline T *
208 378385120 : ggc_cleared_alloc (ALONE_CXX_MEM_STAT_INFO)
209 : {
210 : if (need_finalization_p<T> ())
211 : return static_cast<T *> (ggc_internal_cleared_alloc (sizeof (T),
212 : finalize<T>, 0, 1
213 : PASS_MEM_STAT));
214 : else
215 378385120 : return static_cast<T *> (ggc_internal_cleared_alloc (sizeof (T), NULL, 0, 1
216 : PASS_MEM_STAT));
217 : }
218 :
219 : template<typename T>
220 : inline T *
221 : ggc_vec_alloc (size_t c CXX_MEM_STAT_INFO)
222 : {
223 : if (need_finalization_p<T> ())
224 : return static_cast<T *> (ggc_internal_alloc (c * sizeof (T), finalize<T>,
225 : sizeof (T), c PASS_MEM_STAT));
226 : else
227 : return static_cast<T *> (ggc_internal_alloc (c * sizeof (T), NULL, 0, 0
228 : PASS_MEM_STAT));
229 : }
230 :
231 : template<typename T>
232 : inline T *
233 11065635 : ggc_cleared_vec_alloc (size_t c CXX_MEM_STAT_INFO)
234 : {
235 : if (need_finalization_p<T> ())
236 0 : return static_cast<T *> (ggc_internal_cleared_alloc (c * sizeof (T),
237 : finalize<T>,
238 : sizeof (T), c
239 : PASS_MEM_STAT));
240 : else
241 11065635 : return static_cast<T *> (ggc_internal_cleared_alloc (c * sizeof (T), NULL,
242 : 0, 0 PASS_MEM_STAT));
243 : }
244 :
245 : inline void *
246 2502 : ggc_alloc_atomic (size_t s CXX_MEM_STAT_INFO)
247 : {
248 2502 : return ggc_internal_alloc (s PASS_MEM_STAT);
249 : }
250 :
251 : /* Call destructor and free the garbage collected memory. */
252 :
253 : template <typename T>
254 : inline void
255 : ggc_delete (T *ptr)
256 : {
257 : ptr->~T ();
258 : ggc_free (ptr);
259 : }
260 :
261 : /* Allocate a gc-able string, and fill it with LENGTH bytes from CONTENTS.
262 : If LENGTH is -1, then CONTENTS is assumed to be a
263 : null-terminated string and the memory sized accordingly. */
264 : extern const char *ggc_alloc_string (const char *contents, int length
265 : CXX_MEM_STAT_INFO);
266 :
267 : /* Make a copy of S, in GC-able memory. */
268 : #define ggc_strdup(S) ggc_alloc_string ((S), -1 MEM_STAT_INFO)
269 :
270 : /* Invoke the collector. Garbage collection occurs only when this
271 : function is called, not during allocations. */
272 : enum ggc_collect {
273 : GGC_COLLECT_HEURISTIC,
274 : GGC_COLLECT_FORCE
275 : };
276 : extern void ggc_collect (enum ggc_collect mode = GGC_COLLECT_HEURISTIC);
277 :
278 : /* Return unused memory pages to the system. */
279 : extern void ggc_trim (void);
280 :
281 : /* Assume that all GGC memory is reachable and grow the limits for next collection. */
282 : extern void ggc_grow (void);
283 :
284 : /* Register an additional root table. This can be useful for some
285 : plugins. Does nothing if the passed pointer is NULL. */
286 : extern void ggc_register_root_tab (const struct ggc_root_tab *);
287 :
288 : /* Read objects previously saved with gt_pch_save from F. */
289 : extern void gt_pch_restore (FILE *f);
290 :
291 : /* Statistics. */
292 :
293 : /* Print allocation statistics. */
294 : extern void ggc_print_statistics (void);
295 :
296 : extern void stringpool_statistics (void);
297 :
298 : /* Heuristics. */
299 : extern void init_ggc_heuristics (void);
300 :
301 : /* Report current heap memory use to stderr. */
302 : extern void report_heap_memory_use (void);
303 :
304 : #define ggc_alloc_rtvec_sized(NELT) \
305 : (rtvec_def *) ggc_internal_alloc (sizeof (struct rtvec_def) \
306 : + ((NELT) - 1) * sizeof (rtx)) \
307 :
308 : /* Memory statistics passing versions of some allocators. Too few of them to
309 : make gengtype produce them, so just define the needed ones here. */
310 : inline struct rtx_def *
311 : ggc_alloc_rtx_def_stat (size_t s CXX_MEM_STAT_INFO)
312 : {
313 : return (struct rtx_def *) ggc_internal_alloc (s PASS_MEM_STAT);
314 : }
315 :
316 : inline union tree_node *
317 : ggc_alloc_tree_node_stat (size_t s CXX_MEM_STAT_INFO)
318 : {
319 : return (union tree_node *) ggc_internal_alloc (s PASS_MEM_STAT);
320 : }
321 :
322 : inline union tree_node *
323 253852 : ggc_alloc_cleared_tree_node_stat (size_t s CXX_MEM_STAT_INFO)
324 : {
325 253852 : return (union tree_node *) ggc_internal_cleared_alloc (s PASS_MEM_STAT);
326 : }
327 :
328 : inline gimple *
329 : ggc_alloc_cleared_gimple_statement_stat (size_t s CXX_MEM_STAT_INFO)
330 : {
331 : return (gimple *) ggc_internal_cleared_alloc (s PASS_MEM_STAT);
332 : }
333 :
334 : inline void
335 : gt_ggc_mx (const char *s)
336 : {
337 : ggc_test_and_set_mark (const_cast<char *> (s));
338 : }
339 :
340 : inline void
341 : gt_pch_nx (const char *)
342 : {
343 : }
344 :
345 : inline void gt_pch_nx (bool) { }
346 : inline void gt_pch_nx (char) { }
347 : inline void gt_pch_nx (signed char) { }
348 : inline void gt_pch_nx (unsigned char) { }
349 : inline void gt_pch_nx (short) { }
350 : inline void gt_pch_nx (unsigned short) { }
351 : inline void gt_pch_nx (int) { }
352 : inline void gt_pch_nx (unsigned int) { }
353 : inline void gt_pch_nx (long int) { }
354 : inline void gt_pch_nx (unsigned long int) { }
355 : inline void gt_pch_nx (long long int) { }
356 : inline void gt_pch_nx (unsigned long long int) { }
357 :
358 : inline void gt_ggc_mx (bool) { }
359 : inline void gt_ggc_mx (char) { }
360 : inline void gt_ggc_mx (signed char) { }
361 : inline void gt_ggc_mx (unsigned char) { }
362 : inline void gt_ggc_mx (short) { }
363 : inline void gt_ggc_mx (unsigned short) { }
364 : inline void gt_ggc_mx (int) { }
365 : inline void gt_ggc_mx (unsigned int) { }
366 : inline void gt_ggc_mx (long int) { }
367 : inline void gt_ggc_mx (unsigned long int) { }
368 : inline void gt_ggc_mx (long long int) { }
369 : inline void gt_ggc_mx (unsigned long long int) { }
370 :
371 : #endif
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