* doc/c-tree.texi (Function Bodies): Update HANDLER documentation.
[official-gcc.git] / boehm-gc / finalize.c
blob3b9d9f5ea1ee3804cfbcd17177999c38e6cba500
1 /*
2 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
3 * Copyright (c) 1991-1996 by Xerox Corporation. All rights reserved.
4 * Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
6 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
7 * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
9 * Permission is hereby granted to use or copy this program
10 * for any purpose, provided the above notices are retained on all copies.
11 * Permission to modify the code and to distribute modified code is granted,
12 * provided the above notices are retained, and a notice that the code was
13 * modified is included with the above copyright notice.
15 /* Boehm, February 1, 1996 1:19 pm PST */
16 # define I_HIDE_POINTERS
17 # include "private/gc_pmark.h"
19 # ifdef FINALIZE_ON_DEMAND
20 int GC_finalize_on_demand = 1;
21 # else
22 int GC_finalize_on_demand = 0;
23 # endif
25 # ifdef JAVA_FINALIZATION
26 int GC_java_finalization = 1;
27 # else
28 int GC_java_finalization = 0;
29 # endif
31 /* Type of mark procedure used for marking from finalizable object. */
32 /* This procedure normally does not mark the object, only its */
33 /* descendents. */
34 typedef void finalization_mark_proc(/* ptr_t finalizable_obj_ptr */);
36 # define HASH3(addr,size,log_size) \
37 ((((word)(addr) >> 3) ^ ((word)(addr) >> (3+(log_size)))) \
38 & ((size) - 1))
39 #define HASH2(addr,log_size) HASH3(addr, 1 << log_size, log_size)
41 struct hash_chain_entry {
42 word hidden_key;
43 struct hash_chain_entry * next;
46 unsigned GC_finalization_failures = 0;
47 /* Number of finalization requests that failed for lack of memory. */
49 static struct disappearing_link {
50 struct hash_chain_entry prolog;
51 # define dl_hidden_link prolog.hidden_key
52 /* Field to be cleared. */
53 # define dl_next(x) (struct disappearing_link *)((x) -> prolog.next)
54 # define dl_set_next(x,y) (x) -> prolog.next = (struct hash_chain_entry *)(y)
56 word dl_hidden_obj; /* Pointer to object base */
57 } **dl_head = 0;
59 static signed_word log_dl_table_size = -1;
60 /* Binary log of */
61 /* current size of array pointed to by dl_head. */
62 /* -1 ==> size is 0. */
64 word GC_dl_entries = 0; /* Number of entries currently in disappearing */
65 /* link table. */
67 static struct finalizable_object {
68 struct hash_chain_entry prolog;
69 # define fo_hidden_base prolog.hidden_key
70 /* Pointer to object base. */
71 /* No longer hidden once object */
72 /* is on finalize_now queue. */
73 # define fo_next(x) (struct finalizable_object *)((x) -> prolog.next)
74 # define fo_set_next(x,y) (x) -> prolog.next = (struct hash_chain_entry *)(y)
75 GC_finalization_proc fo_fn; /* Finalizer. */
76 ptr_t fo_client_data;
77 word fo_object_size; /* In bytes. */
78 finalization_mark_proc * fo_mark_proc; /* Mark-through procedure */
79 } **fo_head = 0;
81 struct finalizable_object * GC_finalize_now = 0;
82 /* LIst of objects that should be finalized now. */
84 static signed_word log_fo_table_size = -1;
86 word GC_fo_entries = 0;
88 void GC_push_finalizer_structures GC_PROTO((void))
90 GC_push_all((ptr_t)(&dl_head), (ptr_t)(&dl_head) + sizeof(word));
91 GC_push_all((ptr_t)(&fo_head), (ptr_t)(&fo_head) + sizeof(word));
92 GC_push_all((ptr_t)(&GC_finalize_now),
93 (ptr_t)(&GC_finalize_now) + sizeof(word));
96 /* Double the size of a hash table. *size_ptr is the log of its current */
97 /* size. May be a noop. */
98 /* *table is a pointer to an array of hash headers. If we succeed, we */
99 /* update both *table and *log_size_ptr. */
100 /* Lock is held. Signals are disabled. */
101 void GC_grow_table(table, log_size_ptr)
102 struct hash_chain_entry ***table;
103 signed_word * log_size_ptr;
105 register word i;
106 register struct hash_chain_entry *p;
107 int log_old_size = *log_size_ptr;
108 register int log_new_size = log_old_size + 1;
109 word old_size = ((log_old_size == -1)? 0: (1 << log_old_size));
110 register word new_size = 1 << log_new_size;
111 struct hash_chain_entry **new_table = (struct hash_chain_entry **)
112 GC_INTERNAL_MALLOC_IGNORE_OFF_PAGE(
113 (size_t)new_size * sizeof(struct hash_chain_entry *), NORMAL);
115 if (new_table == 0) {
116 if (table == 0) {
117 ABORT("Insufficient space for initial table allocation");
118 } else {
119 return;
122 for (i = 0; i < old_size; i++) {
123 p = (*table)[i];
124 while (p != 0) {
125 register ptr_t real_key = (ptr_t)REVEAL_POINTER(p -> hidden_key);
126 register struct hash_chain_entry *next = p -> next;
127 register int new_hash = HASH3(real_key, new_size, log_new_size);
129 p -> next = new_table[new_hash];
130 new_table[new_hash] = p;
131 p = next;
134 *log_size_ptr = log_new_size;
135 *table = new_table;
138 # if defined(__STDC__) || defined(__cplusplus)
139 int GC_register_disappearing_link(GC_PTR * link)
140 # else
141 int GC_register_disappearing_link(link)
142 GC_PTR * link;
143 # endif
145 ptr_t base;
147 base = (ptr_t)GC_base((GC_PTR)link);
148 if (base == 0)
149 ABORT("Bad arg to GC_register_disappearing_link");
150 return(GC_general_register_disappearing_link(link, base));
153 # if defined(__STDC__) || defined(__cplusplus)
154 int GC_general_register_disappearing_link(GC_PTR * link,
155 GC_PTR obj)
156 # else
157 int GC_general_register_disappearing_link(link, obj)
158 GC_PTR * link;
159 GC_PTR obj;
160 # endif
163 struct disappearing_link *curr_dl;
164 int index;
165 struct disappearing_link * new_dl;
166 DCL_LOCK_STATE;
168 if ((word)link & (ALIGNMENT-1))
169 ABORT("Bad arg to GC_general_register_disappearing_link");
170 # ifdef THREADS
171 DISABLE_SIGNALS();
172 LOCK();
173 # endif
174 if (log_dl_table_size == -1
175 || GC_dl_entries > ((word)1 << log_dl_table_size)) {
176 # ifndef THREADS
177 DISABLE_SIGNALS();
178 # endif
179 GC_grow_table((struct hash_chain_entry ***)(&dl_head),
180 &log_dl_table_size);
181 # ifdef CONDPRINT
182 if (GC_print_stats) {
183 GC_printf1("Grew dl table to %lu entries\n",
184 (unsigned long)(1 << log_dl_table_size));
186 # endif
187 # ifndef THREADS
188 ENABLE_SIGNALS();
189 # endif
191 index = HASH2(link, log_dl_table_size);
192 curr_dl = dl_head[index];
193 for (curr_dl = dl_head[index]; curr_dl != 0; curr_dl = dl_next(curr_dl)) {
194 if (curr_dl -> dl_hidden_link == HIDE_POINTER(link)) {
195 curr_dl -> dl_hidden_obj = HIDE_POINTER(obj);
196 # ifdef THREADS
197 UNLOCK();
198 ENABLE_SIGNALS();
199 # endif
200 return(1);
203 new_dl = (struct disappearing_link *)
204 GC_INTERNAL_MALLOC(sizeof(struct disappearing_link),NORMAL);
205 if (0 == new_dl) {
206 # ifdef THREADS
207 UNLOCK();
208 ENABLE_SIGNALS();
209 # endif
210 new_dl = (struct disappearing_link *)
211 GC_oom_fn(sizeof(struct disappearing_link));
212 if (0 == new_dl) {
213 GC_finalization_failures++;
214 return(0);
216 /* It's not likely we'll make it here, but ... */
217 # ifdef THREADS
218 DISABLE_SIGNALS();
219 LOCK();
220 # endif
222 new_dl -> dl_hidden_obj = HIDE_POINTER(obj);
223 new_dl -> dl_hidden_link = HIDE_POINTER(link);
224 dl_set_next(new_dl, dl_head[index]);
225 dl_head[index] = new_dl;
226 GC_dl_entries++;
227 # ifdef THREADS
228 UNLOCK();
229 ENABLE_SIGNALS();
230 # endif
231 return(0);
234 # if defined(__STDC__) || defined(__cplusplus)
235 int GC_unregister_disappearing_link(GC_PTR * link)
236 # else
237 int GC_unregister_disappearing_link(link)
238 GC_PTR * link;
239 # endif
241 struct disappearing_link *curr_dl, *prev_dl;
242 int index;
243 DCL_LOCK_STATE;
245 DISABLE_SIGNALS();
246 LOCK();
247 index = HASH2(link, log_dl_table_size);
248 if (((unsigned long)link & (ALIGNMENT-1))) goto out;
249 prev_dl = 0; curr_dl = dl_head[index];
250 while (curr_dl != 0) {
251 if (curr_dl -> dl_hidden_link == HIDE_POINTER(link)) {
252 if (prev_dl == 0) {
253 dl_head[index] = dl_next(curr_dl);
254 } else {
255 dl_set_next(prev_dl, dl_next(curr_dl));
257 GC_dl_entries--;
258 UNLOCK();
259 ENABLE_SIGNALS();
260 # ifdef DBG_HDRS_ALL
261 dl_set_next(curr_dl, 0);
262 # else
263 GC_free((GC_PTR)curr_dl);
264 # endif
265 return(1);
267 prev_dl = curr_dl;
268 curr_dl = dl_next(curr_dl);
270 out:
271 UNLOCK();
272 ENABLE_SIGNALS();
273 return(0);
276 /* Possible finalization_marker procedures. Note that mark stack */
277 /* overflow is handled by the caller, and is not a disaster. */
278 GC_API void GC_normal_finalize_mark_proc(p)
279 ptr_t p;
281 hdr * hhdr = HDR(p);
283 PUSH_OBJ((word *)p, hhdr, GC_mark_stack_top,
284 &(GC_mark_stack[GC_mark_stack_size]));
287 /* This only pays very partial attention to the mark descriptor. */
288 /* It does the right thing for normal and atomic objects, and treats */
289 /* most others as normal. */
290 GC_API void GC_ignore_self_finalize_mark_proc(p)
291 ptr_t p;
293 hdr * hhdr = HDR(p);
294 word descr = hhdr -> hb_descr;
295 ptr_t q, r;
296 ptr_t scan_limit;
297 ptr_t target_limit = p + WORDS_TO_BYTES(hhdr -> hb_sz) - 1;
299 if ((descr & GC_DS_TAGS) == GC_DS_LENGTH) {
300 scan_limit = p + descr - sizeof(word);
301 } else {
302 scan_limit = target_limit + 1 - sizeof(word);
304 for (q = p; q <= scan_limit; q += ALIGNMENT) {
305 r = *(ptr_t *)q;
306 if (r < p || r > target_limit) {
307 GC_PUSH_ONE_HEAP((word)r, q);
312 /*ARGSUSED*/
313 GC_API void GC_null_finalize_mark_proc(p)
314 ptr_t p;
320 /* Register a finalization function. See gc.h for details. */
321 /* in the nonthreads case, we try to avoid disabling signals, */
322 /* since it can be expensive. Threads packages typically */
323 /* make it cheaper. */
324 /* The last parameter is a procedure that determines */
325 /* marking for finalization ordering. Any objects marked */
326 /* by that procedure will be guaranteed to not have been */
327 /* finalized when this finalizer is invoked. */
328 GC_API void GC_register_finalizer_inner(obj, fn, cd, ofn, ocd, mp)
329 GC_PTR obj;
330 GC_finalization_proc fn;
331 GC_PTR cd;
332 GC_finalization_proc * ofn;
333 GC_PTR * ocd;
334 finalization_mark_proc * mp;
336 ptr_t base;
337 struct finalizable_object * curr_fo, * prev_fo;
338 int index;
339 struct finalizable_object *new_fo;
340 hdr *hhdr;
341 DCL_LOCK_STATE;
343 # ifdef THREADS
344 DISABLE_SIGNALS();
345 LOCK();
346 # endif
347 if (log_fo_table_size == -1
348 || GC_fo_entries > ((word)1 << log_fo_table_size)) {
349 # ifndef THREADS
350 DISABLE_SIGNALS();
351 # endif
352 GC_grow_table((struct hash_chain_entry ***)(&fo_head),
353 &log_fo_table_size);
354 # ifdef CONDPRINT
355 if (GC_print_stats) {
356 GC_printf1("Grew fo table to %lu entries\n",
357 (unsigned long)(1 << log_fo_table_size));
359 # endif
360 # ifndef THREADS
361 ENABLE_SIGNALS();
362 # endif
364 /* in the THREADS case signals are disabled and we hold allocation */
365 /* lock; otherwise neither is true. Proceed carefully. */
366 base = (ptr_t)obj;
367 index = HASH2(base, log_fo_table_size);
368 prev_fo = 0; curr_fo = fo_head[index];
369 while (curr_fo != 0) {
370 if (curr_fo -> fo_hidden_base == HIDE_POINTER(base)) {
371 /* Interruption by a signal in the middle of this */
372 /* should be safe. The client may see only *ocd */
373 /* updated, but we'll declare that to be his */
374 /* problem. */
375 if (ocd) *ocd = (GC_PTR) curr_fo -> fo_client_data;
376 if (ofn) *ofn = curr_fo -> fo_fn;
377 /* Delete the structure for base. */
378 if (prev_fo == 0) {
379 fo_head[index] = fo_next(curr_fo);
380 } else {
381 fo_set_next(prev_fo, fo_next(curr_fo));
383 if (fn == 0) {
384 GC_fo_entries--;
385 /* May not happen if we get a signal. But a high */
386 /* estimate will only make the table larger than */
387 /* necessary. */
388 # if !defined(THREADS) && !defined(DBG_HDRS_ALL)
389 GC_free((GC_PTR)curr_fo);
390 # endif
391 } else {
392 curr_fo -> fo_fn = fn;
393 curr_fo -> fo_client_data = (ptr_t)cd;
394 curr_fo -> fo_mark_proc = mp;
395 /* Reinsert it. We deleted it first to maintain */
396 /* consistency in the event of a signal. */
397 if (prev_fo == 0) {
398 fo_head[index] = curr_fo;
399 } else {
400 fo_set_next(prev_fo, curr_fo);
403 # ifdef THREADS
404 UNLOCK();
405 ENABLE_SIGNALS();
406 # endif
407 return;
409 prev_fo = curr_fo;
410 curr_fo = fo_next(curr_fo);
412 if (ofn) *ofn = 0;
413 if (ocd) *ocd = 0;
414 if (fn == 0) {
415 # ifdef THREADS
416 UNLOCK();
417 ENABLE_SIGNALS();
418 # endif
419 return;
421 GET_HDR(base, hhdr);
422 if (0 == hhdr) {
423 /* We won't collect it, hence finalizer wouldn't be run. */
424 # ifdef THREADS
425 UNLOCK();
426 ENABLE_SIGNALS();
427 # endif
428 return;
430 new_fo = (struct finalizable_object *)
431 GC_INTERNAL_MALLOC(sizeof(struct finalizable_object),NORMAL);
432 if (0 == new_fo) {
433 # ifdef THREADS
434 UNLOCK();
435 ENABLE_SIGNALS();
436 # endif
437 new_fo = (struct finalizable_object *)
438 GC_oom_fn(sizeof(struct finalizable_object));
439 if (0 == new_fo) {
440 GC_finalization_failures++;
441 return;
443 /* It's not likely we'll make it here, but ... */
444 # ifdef THREADS
445 DISABLE_SIGNALS();
446 LOCK();
447 # endif
449 new_fo -> fo_hidden_base = (word)HIDE_POINTER(base);
450 new_fo -> fo_fn = fn;
451 new_fo -> fo_client_data = (ptr_t)cd;
452 new_fo -> fo_object_size = hhdr -> hb_sz;
453 new_fo -> fo_mark_proc = mp;
454 fo_set_next(new_fo, fo_head[index]);
455 GC_fo_entries++;
456 fo_head[index] = new_fo;
457 # ifdef THREADS
458 UNLOCK();
459 ENABLE_SIGNALS();
460 # endif
463 # if defined(__STDC__)
464 void GC_register_finalizer(void * obj,
465 GC_finalization_proc fn, void * cd,
466 GC_finalization_proc *ofn, void ** ocd)
467 # else
468 void GC_register_finalizer(obj, fn, cd, ofn, ocd)
469 GC_PTR obj;
470 GC_finalization_proc fn;
471 GC_PTR cd;
472 GC_finalization_proc * ofn;
473 GC_PTR * ocd;
474 # endif
476 GC_register_finalizer_inner(obj, fn, cd, ofn,
477 ocd, GC_normal_finalize_mark_proc);
480 # if defined(__STDC__)
481 void GC_register_finalizer_ignore_self(void * obj,
482 GC_finalization_proc fn, void * cd,
483 GC_finalization_proc *ofn, void ** ocd)
484 # else
485 void GC_register_finalizer_ignore_self(obj, fn, cd, ofn, ocd)
486 GC_PTR obj;
487 GC_finalization_proc fn;
488 GC_PTR cd;
489 GC_finalization_proc * ofn;
490 GC_PTR * ocd;
491 # endif
493 GC_register_finalizer_inner(obj, fn, cd, ofn,
494 ocd, GC_ignore_self_finalize_mark_proc);
497 # if defined(__STDC__)
498 void GC_register_finalizer_no_order(void * obj,
499 GC_finalization_proc fn, void * cd,
500 GC_finalization_proc *ofn, void ** ocd)
501 # else
502 void GC_register_finalizer_no_order(obj, fn, cd, ofn, ocd)
503 GC_PTR obj;
504 GC_finalization_proc fn;
505 GC_PTR cd;
506 GC_finalization_proc * ofn;
507 GC_PTR * ocd;
508 # endif
510 GC_register_finalizer_inner(obj, fn, cd, ofn,
511 ocd, GC_null_finalize_mark_proc);
514 #ifndef NO_DEBUGGING
515 void GC_dump_finalization()
517 struct disappearing_link * curr_dl;
518 struct finalizable_object * curr_fo;
519 ptr_t real_ptr, real_link;
520 int dl_size = (log_dl_table_size == -1 ) ? 0 : (1 << log_dl_table_size);
521 int fo_size = (log_fo_table_size == -1 ) ? 0 : (1 << log_fo_table_size);
522 int i;
524 GC_printf0("Disappearing links:\n");
525 for (i = 0; i < dl_size; i++) {
526 for (curr_dl = dl_head[i]; curr_dl != 0; curr_dl = dl_next(curr_dl)) {
527 real_ptr = (ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_obj);
528 real_link = (ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_link);
529 GC_printf2("Object: 0x%lx, Link:0x%lx\n", real_ptr, real_link);
532 GC_printf0("Finalizers:\n");
533 for (i = 0; i < fo_size; i++) {
534 for (curr_fo = fo_head[i]; curr_fo != 0; curr_fo = fo_next(curr_fo)) {
535 real_ptr = (ptr_t)REVEAL_POINTER(curr_fo -> fo_hidden_base);
536 GC_printf1("Finalizable object: 0x%lx\n", real_ptr);
540 #endif
542 /* Called with world stopped. Cause disappearing links to disappear, */
543 /* and invoke finalizers. */
544 void GC_finalize()
546 struct disappearing_link * curr_dl, * prev_dl, * next_dl;
547 struct finalizable_object * curr_fo, * prev_fo, * next_fo;
548 ptr_t real_ptr, real_link;
549 register int i;
550 int dl_size = (log_dl_table_size == -1 ) ? 0 : (1 << log_dl_table_size);
551 int fo_size = (log_fo_table_size == -1 ) ? 0 : (1 << log_fo_table_size);
553 /* Make disappearing links disappear */
554 for (i = 0; i < dl_size; i++) {
555 curr_dl = dl_head[i];
556 prev_dl = 0;
557 while (curr_dl != 0) {
558 real_ptr = (ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_obj);
559 real_link = (ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_link);
560 if (!GC_is_marked(real_ptr)) {
561 *(word *)real_link = 0;
562 next_dl = dl_next(curr_dl);
563 if (prev_dl == 0) {
564 dl_head[i] = next_dl;
565 } else {
566 dl_set_next(prev_dl, next_dl);
568 GC_clear_mark_bit((ptr_t)curr_dl);
569 GC_dl_entries--;
570 curr_dl = next_dl;
571 } else {
572 prev_dl = curr_dl;
573 curr_dl = dl_next(curr_dl);
577 /* Mark all objects reachable via chains of 1 or more pointers */
578 /* from finalizable objects. */
579 GC_ASSERT(GC_mark_state == MS_NONE);
580 for (i = 0; i < fo_size; i++) {
581 for (curr_fo = fo_head[i]; curr_fo != 0; curr_fo = fo_next(curr_fo)) {
582 real_ptr = (ptr_t)REVEAL_POINTER(curr_fo -> fo_hidden_base);
583 if (!GC_is_marked(real_ptr)) {
584 GC_MARKED_FOR_FINALIZATION(real_ptr);
585 GC_MARK_FO(real_ptr, curr_fo -> fo_mark_proc);
586 if (GC_is_marked(real_ptr)) {
587 WARN("Finalization cycle involving %lx\n", real_ptr);
592 /* Enqueue for finalization all objects that are still */
593 /* unreachable. */
594 GC_words_finalized = 0;
595 for (i = 0; i < fo_size; i++) {
596 curr_fo = fo_head[i];
597 prev_fo = 0;
598 while (curr_fo != 0) {
599 real_ptr = (ptr_t)REVEAL_POINTER(curr_fo -> fo_hidden_base);
600 if (!GC_is_marked(real_ptr)) {
601 if (!GC_java_finalization) {
602 GC_set_mark_bit(real_ptr);
604 /* Delete from hash table */
605 next_fo = fo_next(curr_fo);
606 if (prev_fo == 0) {
607 fo_head[i] = next_fo;
608 } else {
609 fo_set_next(prev_fo, next_fo);
611 GC_fo_entries--;
612 /* Add to list of objects awaiting finalization. */
613 fo_set_next(curr_fo, GC_finalize_now);
614 GC_finalize_now = curr_fo;
615 /* unhide object pointer so any future collections will */
616 /* see it. */
617 curr_fo -> fo_hidden_base =
618 (word) REVEAL_POINTER(curr_fo -> fo_hidden_base);
619 GC_words_finalized +=
620 ALIGNED_WORDS(curr_fo -> fo_object_size)
621 + ALIGNED_WORDS(sizeof(struct finalizable_object));
622 GC_ASSERT(GC_is_marked(GC_base((ptr_t)curr_fo)));
623 curr_fo = next_fo;
624 } else {
625 prev_fo = curr_fo;
626 curr_fo = fo_next(curr_fo);
631 if (GC_java_finalization) {
632 /* make sure we mark everything reachable from objects finalized
633 using the no_order mark_proc */
634 for (curr_fo = GC_finalize_now;
635 curr_fo != NULL; curr_fo = fo_next(curr_fo)) {
636 real_ptr = (ptr_t)curr_fo -> fo_hidden_base;
637 if (!GC_is_marked(real_ptr)) {
638 if (curr_fo -> fo_mark_proc == GC_null_finalize_mark_proc) {
639 GC_MARK_FO(real_ptr, GC_normal_finalize_mark_proc);
641 GC_set_mark_bit(real_ptr);
646 /* Remove dangling disappearing links. */
647 for (i = 0; i < dl_size; i++) {
648 curr_dl = dl_head[i];
649 prev_dl = 0;
650 while (curr_dl != 0) {
651 real_link = GC_base((ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_link));
652 if (real_link != 0 && !GC_is_marked(real_link)) {
653 next_dl = dl_next(curr_dl);
654 if (prev_dl == 0) {
655 dl_head[i] = next_dl;
656 } else {
657 dl_set_next(prev_dl, next_dl);
659 GC_clear_mark_bit((ptr_t)curr_dl);
660 GC_dl_entries--;
661 curr_dl = next_dl;
662 } else {
663 prev_dl = curr_dl;
664 curr_dl = dl_next(curr_dl);
670 #ifndef JAVA_FINALIZATION_NOT_NEEDED
672 /* Enqueue all remaining finalizers to be run - Assumes lock is
673 * held, and signals are disabled */
674 void GC_enqueue_all_finalizers()
676 struct finalizable_object * curr_fo, * prev_fo, * next_fo;
677 ptr_t real_ptr;
678 register int i;
679 int fo_size;
681 fo_size = (log_fo_table_size == -1 ) ? 0 : (1 << log_fo_table_size);
682 GC_words_finalized = 0;
683 for (i = 0; i < fo_size; i++) {
684 curr_fo = fo_head[i];
685 prev_fo = 0;
686 while (curr_fo != 0) {
687 real_ptr = (ptr_t)REVEAL_POINTER(curr_fo -> fo_hidden_base);
688 GC_MARK_FO(real_ptr, GC_normal_finalize_mark_proc);
689 GC_set_mark_bit(real_ptr);
691 /* Delete from hash table */
692 next_fo = fo_next(curr_fo);
693 if (prev_fo == 0) {
694 fo_head[i] = next_fo;
695 } else {
696 fo_set_next(prev_fo, next_fo);
698 GC_fo_entries--;
700 /* Add to list of objects awaiting finalization. */
701 fo_set_next(curr_fo, GC_finalize_now);
702 GC_finalize_now = curr_fo;
704 /* unhide object pointer so any future collections will */
705 /* see it. */
706 curr_fo -> fo_hidden_base =
707 (word) REVEAL_POINTER(curr_fo -> fo_hidden_base);
709 GC_words_finalized +=
710 ALIGNED_WORDS(curr_fo -> fo_object_size)
711 + ALIGNED_WORDS(sizeof(struct finalizable_object));
712 curr_fo = next_fo;
716 return;
719 /* Invoke all remaining finalizers that haven't yet been run.
720 * This is needed for strict compliance with the Java standard,
721 * which can make the runtime guarantee that all finalizers are run.
722 * Unfortunately, the Java standard implies we have to keep running
723 * finalizers until there are no more left, a potential infinite loop.
724 * YUCK.
725 * Note that this is even more dangerous than the usual Java
726 * finalizers, in that objects reachable from static variables
727 * may have been finalized when these finalizers are run.
728 * Finalizers run at this point must be prepared to deal with a
729 * mostly broken world.
730 * This routine is externally callable, so is called without
731 * the allocation lock.
733 GC_API void GC_finalize_all()
735 DCL_LOCK_STATE;
737 DISABLE_SIGNALS();
738 LOCK();
739 while (GC_fo_entries > 0) {
740 GC_enqueue_all_finalizers();
741 UNLOCK();
742 ENABLE_SIGNALS();
743 GC_INVOKE_FINALIZERS();
744 DISABLE_SIGNALS();
745 LOCK();
747 UNLOCK();
748 ENABLE_SIGNALS();
750 #endif
752 /* Returns true if it is worth calling GC_invoke_finalizers. (Useful if */
753 /* finalizers can only be called from some kind of `safe state' and */
754 /* getting into that safe state is expensive.) */
755 int GC_should_invoke_finalizers GC_PROTO((void))
757 return GC_finalize_now != 0;
760 /* Invoke finalizers for all objects that are ready to be finalized. */
761 /* Should be called without allocation lock. */
762 int GC_invoke_finalizers()
764 struct finalizable_object * curr_fo;
765 int count = 0;
766 word mem_freed_before;
767 DCL_LOCK_STATE;
769 while (GC_finalize_now != 0) {
770 # ifdef THREADS
771 DISABLE_SIGNALS();
772 LOCK();
773 # endif
774 if (count == 0) {
775 mem_freed_before = GC_mem_freed;
777 curr_fo = GC_finalize_now;
778 # ifdef THREADS
779 if (curr_fo != 0) GC_finalize_now = fo_next(curr_fo);
780 UNLOCK();
781 ENABLE_SIGNALS();
782 if (curr_fo == 0) break;
783 # else
784 GC_finalize_now = fo_next(curr_fo);
785 # endif
786 fo_set_next(curr_fo, 0);
787 (*(curr_fo -> fo_fn))((ptr_t)(curr_fo -> fo_hidden_base),
788 curr_fo -> fo_client_data);
789 curr_fo -> fo_client_data = 0;
790 ++count;
791 # ifdef UNDEFINED
792 /* This is probably a bad idea. It throws off accounting if */
793 /* nearly all objects are finalizable. O.w. it shouldn't */
794 /* matter. */
795 GC_free((GC_PTR)curr_fo);
796 # endif
798 if (count != 0 && mem_freed_before != GC_mem_freed) {
799 LOCK();
800 GC_finalizer_mem_freed += (GC_mem_freed - mem_freed_before);
801 UNLOCK();
803 return count;
806 void (* GC_finalizer_notifier)() = (void (*) GC_PROTO((void)))0;
808 static GC_word last_finalizer_notification = 0;
810 void GC_notify_or_invoke_finalizers GC_PROTO((void))
812 if (GC_finalize_now == 0) return;
813 if (!GC_finalize_on_demand) {
814 (void) GC_invoke_finalizers();
815 # ifndef THREADS
816 GC_ASSERT(GC_finalize_now == 0);
817 # endif /* Otherwise GC can run concurrently and add more */
818 return;
820 if (GC_finalizer_notifier != (void (*) GC_PROTO((void)))0
821 && last_finalizer_notification != GC_gc_no) {
822 last_finalizer_notification = GC_gc_no;
823 GC_finalizer_notifier();
827 # ifdef __STDC__
828 GC_PTR GC_call_with_alloc_lock(GC_fn_type fn,
829 GC_PTR client_data)
830 # else
831 GC_PTR GC_call_with_alloc_lock(fn, client_data)
832 GC_fn_type fn;
833 GC_PTR client_data;
834 # endif
836 GC_PTR result;
837 DCL_LOCK_STATE;
839 # ifdef THREADS
840 DISABLE_SIGNALS();
841 LOCK();
842 SET_LOCK_HOLDER();
843 # endif
844 result = (*fn)(client_data);
845 # ifdef THREADS
846 # ifndef GC_ASSERTIONS
847 UNSET_LOCK_HOLDER();
848 # endif /* o.w. UNLOCK() does it implicitly */
849 UNLOCK();
850 ENABLE_SIGNALS();
851 # endif
852 return(result);
855 #if !defined(NO_DEBUGGING)
857 void GC_print_finalization_stats()
859 struct finalizable_object *fo = GC_finalize_now;
860 size_t ready = 0;
862 GC_printf2("%lu finalization table entries; %lu disappearing links\n",
863 GC_fo_entries, GC_dl_entries);
864 for (; 0 != fo; fo = fo_next(fo)) ++ready;
865 GC_printf1("%lu objects are eligible for immediate finalization\n", ready);
868 #endif /* NO_DEBUGGING */