source: trunk/src/gcc/boehm-gc/finalize.c@ 1530

Last change on this file since 1530 was 2, checked in by bird, 23 years ago

Initial revision
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  • Property svn:executable set to *
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Line 
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.
5
6 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
7 * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
8 *
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.
14 */
15/* Boehm, February 1, 1996 1:19 pm PST */
16# define I_HIDE_POINTERS
17# include "private/gc_pmark.h"
18
19# ifdef FINALIZE_ON_DEMAND
20 int GC_finalize_on_demand = 1;
21# else
22 int GC_finalize_on_demand = 0;
23# endif
24
25# ifdef JAVA_FINALIZATION
26 int GC_java_finalization = 1;
27# else
28 int GC_java_finalization = 0;
29# endif
30
31/* Type of mark procedure used for marking from finalizable object. */
32/* This procedure normally does not mark the object, only its */
33/* descendents. */
34typedef void finalization_mark_proc(/* ptr_t finalizable_obj_ptr */);
35
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)
40
41struct hash_chain_entry {
42 word hidden_key;
43 struct hash_chain_entry * next;
44};
45
46unsigned GC_finalization_failures = 0;
47 /* Number of finalization requests that failed for lack of memory. */
48
49static 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)
55
56 word dl_hidden_obj; /* Pointer to object base */
57} **dl_head = 0;
58
59static 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. */
63
64word GC_dl_entries = 0; /* Number of entries currently in disappearing */
65 /* link table. */
66
67static 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;
80
81struct finalizable_object * GC_finalize_now = 0;
82 /* LIst of objects that should be finalized now. */
83
84static signed_word log_fo_table_size = -1;
85
86word GC_fo_entries = 0;
87
88void GC_push_finalizer_structures GC_PROTO((void))
89{
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));
94}
95
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. */
101void GC_grow_table(table, log_size_ptr)
102struct hash_chain_entry ***table;
103signed_word * log_size_ptr;
104{
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);
114
115 if (new_table == 0) {
116 if (table == 0) {
117 ABORT("Insufficient space for initial table allocation");
118 } else {
119 return;
120 }
121 }
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);
128
129 p -> next = new_table[new_hash];
130 new_table[new_hash] = p;
131 p = next;
132 }
133 }
134 *log_size_ptr = log_new_size;
135 *table = new_table;
136}
137
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
144{
145 ptr_t base;
146
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));
151}
152
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
161
162{
163 struct disappearing_link *curr_dl;
164 int index;
165 struct disappearing_link * new_dl;
166 DCL_LOCK_STATE;
167
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));
185 }
186# endif
187# ifndef THREADS
188 ENABLE_SIGNALS();
189# endif
190 }
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);
201 }
202 }
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 = GC_oom_fn(sizeof(struct disappearing_link));
211 if (0 == new_dl) {
212 GC_finalization_failures++;
213 return(0);
214 }
215 /* It's not likely we'll make it here, but ... */
216# ifdef THREADS
217 DISABLE_SIGNALS();
218 LOCK();
219# endif
220 }
221 new_dl -> dl_hidden_obj = HIDE_POINTER(obj);
222 new_dl -> dl_hidden_link = HIDE_POINTER(link);
223 dl_set_next(new_dl, dl_head[index]);
224 dl_head[index] = new_dl;
225 GC_dl_entries++;
226# ifdef THREADS
227 UNLOCK();
228 ENABLE_SIGNALS();
229# endif
230 return(0);
231}
232
233# if defined(__STDC__) || defined(__cplusplus)
234 int GC_unregister_disappearing_link(GC_PTR * link)
235# else
236 int GC_unregister_disappearing_link(link)
237 GC_PTR * link;
238# endif
239{
240 struct disappearing_link *curr_dl, *prev_dl;
241 int index;
242 DCL_LOCK_STATE;
243
244 DISABLE_SIGNALS();
245 LOCK();
246 index = HASH2(link, log_dl_table_size);
247 if (((unsigned long)link & (ALIGNMENT-1))) goto out;
248 prev_dl = 0; curr_dl = dl_head[index];
249 while (curr_dl != 0) {
250 if (curr_dl -> dl_hidden_link == HIDE_POINTER(link)) {
251 if (prev_dl == 0) {
252 dl_head[index] = dl_next(curr_dl);
253 } else {
254 dl_set_next(prev_dl, dl_next(curr_dl));
255 }
256 GC_dl_entries--;
257 UNLOCK();
258 ENABLE_SIGNALS();
259# ifdef DBG_HDRS_ALL
260 dl_set_next(curr_dl, 0);
261# else
262 GC_free((GC_PTR)curr_dl);
263# endif
264 return(1);
265 }
266 prev_dl = curr_dl;
267 curr_dl = dl_next(curr_dl);
268 }
269out:
270 UNLOCK();
271 ENABLE_SIGNALS();
272 return(0);
273}
274
275/* Possible finalization_marker procedures. Note that mark stack */
276/* overflow is handled by the caller, and is not a disaster. */
277GC_API void GC_normal_finalize_mark_proc(p)
278ptr_t p;
279{
280 hdr * hhdr = HDR(p);
281
282 PUSH_OBJ((word *)p, hhdr, GC_mark_stack_top,
283 &(GC_mark_stack[GC_mark_stack_size]));
284}
285
286/* This only pays very partial attention to the mark descriptor. */
287/* It does the right thing for normal and atomic objects, and treats */
288/* most others as normal. */
289GC_API void GC_ignore_self_finalize_mark_proc(p)
290ptr_t p;
291{
292 hdr * hhdr = HDR(p);
293 word descr = hhdr -> hb_descr;
294 ptr_t q, r;
295 ptr_t scan_limit;
296 ptr_t target_limit = p + WORDS_TO_BYTES(hhdr -> hb_sz) - 1;
297
298 if ((descr & GC_DS_TAGS) == GC_DS_LENGTH) {
299 scan_limit = p + descr - sizeof(word);
300 } else {
301 scan_limit = target_limit + 1 - sizeof(word);
302 }
303 for (q = p; q <= scan_limit; q += ALIGNMENT) {
304 r = *(ptr_t *)q;
305 if (r < p || r > target_limit) {
306 GC_PUSH_ONE_HEAP((word)r, q);
307 }
308 }
309}
310
311/*ARGSUSED*/
312GC_API void GC_null_finalize_mark_proc(p)
313ptr_t p;
314{
315}
316
317
318
319/* Register a finalization function. See gc.h for details. */
320/* in the nonthreads case, we try to avoid disabling signals, */
321/* since it can be expensive. Threads packages typically */
322/* make it cheaper. */
323/* The last parameter is a procedure that determines */
324/* marking for finalization ordering. Any objects marked */
325/* by that procedure will be guaranteed to not have been */
326/* finalized when this finalizer is invoked. */
327GC_API void GC_register_finalizer_inner(obj, fn, cd, ofn, ocd, mp)
328GC_PTR obj;
329GC_finalization_proc fn;
330GC_PTR cd;
331GC_finalization_proc * ofn;
332GC_PTR * ocd;
333finalization_mark_proc * mp;
334{
335 ptr_t base;
336 struct finalizable_object * curr_fo, * prev_fo;
337 int index;
338 struct finalizable_object *new_fo;
339 hdr *hhdr;
340 DCL_LOCK_STATE;
341
342# ifdef THREADS
343 DISABLE_SIGNALS();
344 LOCK();
345# endif
346 if (log_fo_table_size == -1
347 || GC_fo_entries > ((word)1 << log_fo_table_size)) {
348# ifndef THREADS
349 DISABLE_SIGNALS();
350# endif
351 GC_grow_table((struct hash_chain_entry ***)(&fo_head),
352 &log_fo_table_size);
353# ifdef CONDPRINT
354 if (GC_print_stats) {
355 GC_printf1("Grew fo table to %lu entries\n",
356 (unsigned long)(1 << log_fo_table_size));
357 }
358# endif
359# ifndef THREADS
360 ENABLE_SIGNALS();
361# endif
362 }
363 /* in the THREADS case signals are disabled and we hold allocation */
364 /* lock; otherwise neither is true. Proceed carefully. */
365 base = (ptr_t)obj;
366 index = HASH2(base, log_fo_table_size);
367 prev_fo = 0; curr_fo = fo_head[index];
368 while (curr_fo != 0) {
369 if (curr_fo -> fo_hidden_base == HIDE_POINTER(base)) {
370 /* Interruption by a signal in the middle of this */
371 /* should be safe. The client may see only *ocd */
372 /* updated, but we'll declare that to be his */
373 /* problem. */
374 if (ocd) *ocd = (GC_PTR) curr_fo -> fo_client_data;
375 if (ofn) *ofn = curr_fo -> fo_fn;
376 /* Delete the structure for base. */
377 if (prev_fo == 0) {
378 fo_head[index] = fo_next(curr_fo);
379 } else {
380 fo_set_next(prev_fo, fo_next(curr_fo));
381 }
382 if (fn == 0) {
383 GC_fo_entries--;
384 /* May not happen if we get a signal. But a high */
385 /* estimate will only make the table larger than */
386 /* necessary. */
387# if !defined(THREADS) && !defined(DBG_HDRS_ALL)
388 GC_free((GC_PTR)curr_fo);
389# endif
390 } else {
391 curr_fo -> fo_fn = fn;
392 curr_fo -> fo_client_data = (ptr_t)cd;
393 curr_fo -> fo_mark_proc = mp;
394 /* Reinsert it. We deleted it first to maintain */
395 /* consistency in the event of a signal. */
396 if (prev_fo == 0) {
397 fo_head[index] = curr_fo;
398 } else {
399 fo_set_next(prev_fo, curr_fo);
400 }
401 }
402# ifdef THREADS
403 UNLOCK();
404 ENABLE_SIGNALS();
405# endif
406 return;
407 }
408 prev_fo = curr_fo;
409 curr_fo = fo_next(curr_fo);
410 }
411 if (ofn) *ofn = 0;
412 if (ocd) *ocd = 0;
413 if (fn == 0) {
414# ifdef THREADS
415 UNLOCK();
416 ENABLE_SIGNALS();
417# endif
418 return;
419 }
420 GET_HDR(base, hhdr);
421 if (0 == hhdr) {
422 /* We won't collect it, hence finalizer wouldn't be run. */
423# ifdef THREADS
424 UNLOCK();
425 ENABLE_SIGNALS();
426# endif
427 return;
428 }
429 new_fo = (struct finalizable_object *)
430 GC_INTERNAL_MALLOC(sizeof(struct finalizable_object),NORMAL);
431 if (0 == new_fo) {
432# ifdef THREADS
433 UNLOCK();
434 ENABLE_SIGNALS();
435# endif
436 new_fo = GC_oom_fn(sizeof(struct finalizable_object));
437 if (0 == new_fo) {
438 GC_finalization_failures++;
439 return;
440 }
441 /* It's not likely we'll make it here, but ... */
442# ifdef THREADS
443 DISABLE_SIGNALS();
444 LOCK();
445# endif
446 }
447 new_fo -> fo_hidden_base = (word)HIDE_POINTER(base);
448 new_fo -> fo_fn = fn;
449 new_fo -> fo_client_data = (ptr_t)cd;
450 new_fo -> fo_object_size = hhdr -> hb_sz;
451 new_fo -> fo_mark_proc = mp;
452 fo_set_next(new_fo, fo_head[index]);
453 GC_fo_entries++;
454 fo_head[index] = new_fo;
455# ifdef THREADS
456 UNLOCK();
457 ENABLE_SIGNALS();
458# endif
459}
460
461# if defined(__STDC__)
462 void GC_register_finalizer(void * obj,
463 GC_finalization_proc fn, void * cd,
464 GC_finalization_proc *ofn, void ** ocd)
465# else
466 void GC_register_finalizer(obj, fn, cd, ofn, ocd)
467 GC_PTR obj;
468 GC_finalization_proc fn;
469 GC_PTR cd;
470 GC_finalization_proc * ofn;
471 GC_PTR * ocd;
472# endif
473{
474 GC_register_finalizer_inner(obj, fn, cd, ofn,
475 ocd, GC_normal_finalize_mark_proc);
476}
477
478# if defined(__STDC__)
479 void GC_register_finalizer_ignore_self(void * obj,
480 GC_finalization_proc fn, void * cd,
481 GC_finalization_proc *ofn, void ** ocd)
482# else
483 void GC_register_finalizer_ignore_self(obj, fn, cd, ofn, ocd)
484 GC_PTR obj;
485 GC_finalization_proc fn;
486 GC_PTR cd;
487 GC_finalization_proc * ofn;
488 GC_PTR * ocd;
489# endif
490{
491 GC_register_finalizer_inner(obj, fn, cd, ofn,
492 ocd, GC_ignore_self_finalize_mark_proc);
493}
494
495# if defined(__STDC__)
496 void GC_register_finalizer_no_order(void * obj,
497 GC_finalization_proc fn, void * cd,
498 GC_finalization_proc *ofn, void ** ocd)
499# else
500 void GC_register_finalizer_no_order(obj, fn, cd, ofn, ocd)
501 GC_PTR obj;
502 GC_finalization_proc fn;
503 GC_PTR cd;
504 GC_finalization_proc * ofn;
505 GC_PTR * ocd;
506# endif
507{
508 GC_register_finalizer_inner(obj, fn, cd, ofn,
509 ocd, GC_null_finalize_mark_proc);
510}
511
512#ifndef NO_DEBUGGING
513void GC_dump_finalization()
514{
515 struct disappearing_link * curr_dl;
516 struct finalizable_object * curr_fo;
517 ptr_t real_ptr, real_link;
518 int dl_size = (log_dl_table_size == -1 ) ? 0 : (1 << log_dl_table_size);
519 int fo_size = (log_fo_table_size == -1 ) ? 0 : (1 << log_fo_table_size);
520 int i;
521
522 GC_printf0("Disappearing links:\n");
523 for (i = 0; i < dl_size; i++) {
524 for (curr_dl = dl_head[i]; curr_dl != 0; curr_dl = dl_next(curr_dl)) {
525 real_ptr = (ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_obj);
526 real_link = (ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_link);
527 GC_printf2("Object: 0x%lx, Link:0x%lx\n", real_ptr, real_link);
528 }
529 }
530 GC_printf0("Finalizers:\n");
531 for (i = 0; i < fo_size; i++) {
532 for (curr_fo = fo_head[i]; curr_fo != 0; curr_fo = fo_next(curr_fo)) {
533 real_ptr = (ptr_t)REVEAL_POINTER(curr_fo -> fo_hidden_base);
534 GC_printf1("Finalizable object: 0x%lx\n", real_ptr);
535 }
536 }
537}
538#endif
539
540/* Called with world stopped. Cause disappearing links to disappear, */
541/* and invoke finalizers. */
542void GC_finalize()
543{
544 struct disappearing_link * curr_dl, * prev_dl, * next_dl;
545 struct finalizable_object * curr_fo, * prev_fo, * next_fo;
546 ptr_t real_ptr, real_link;
547 register int i;
548 int dl_size = (log_dl_table_size == -1 ) ? 0 : (1 << log_dl_table_size);
549 int fo_size = (log_fo_table_size == -1 ) ? 0 : (1 << log_fo_table_size);
550
551 /* Make disappearing links disappear */
552 for (i = 0; i < dl_size; i++) {
553 curr_dl = dl_head[i];
554 prev_dl = 0;
555 while (curr_dl != 0) {
556 real_ptr = (ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_obj);
557 real_link = (ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_link);
558 if (!GC_is_marked(real_ptr)) {
559 *(word *)real_link = 0;
560 next_dl = dl_next(curr_dl);
561 if (prev_dl == 0) {
562 dl_head[i] = next_dl;
563 } else {
564 dl_set_next(prev_dl, next_dl);
565 }
566 GC_clear_mark_bit((ptr_t)curr_dl);
567 GC_dl_entries--;
568 curr_dl = next_dl;
569 } else {
570 prev_dl = curr_dl;
571 curr_dl = dl_next(curr_dl);
572 }
573 }
574 }
575 /* Mark all objects reachable via chains of 1 or more pointers */
576 /* from finalizable objects. */
577 GC_ASSERT(GC_mark_state == MS_NONE);
578 for (i = 0; i < fo_size; i++) {
579 for (curr_fo = fo_head[i]; curr_fo != 0; curr_fo = fo_next(curr_fo)) {
580 real_ptr = (ptr_t)REVEAL_POINTER(curr_fo -> fo_hidden_base);
581 if (!GC_is_marked(real_ptr)) {
582 GC_MARKED_FOR_FINALIZATION(real_ptr);
583 GC_MARK_FO(real_ptr, curr_fo -> fo_mark_proc);
584 if (GC_is_marked(real_ptr)) {
585 WARN("Finalization cycle involving %lx\n", real_ptr);
586 }
587 }
588 }
589 }
590 /* Enqueue for finalization all objects that are still */
591 /* unreachable. */
592 GC_words_finalized = 0;
593 for (i = 0; i < fo_size; i++) {
594 curr_fo = fo_head[i];
595 prev_fo = 0;
596 while (curr_fo != 0) {
597 real_ptr = (ptr_t)REVEAL_POINTER(curr_fo -> fo_hidden_base);
598 if (!GC_is_marked(real_ptr)) {
599 if (!GC_java_finalization) {
600 GC_set_mark_bit(real_ptr);
601 }
602 /* Delete from hash table */
603 next_fo = fo_next(curr_fo);
604 if (prev_fo == 0) {
605 fo_head[i] = next_fo;
606 } else {
607 fo_set_next(prev_fo, next_fo);
608 }
609 GC_fo_entries--;
610 /* Add to list of objects awaiting finalization. */
611 fo_set_next(curr_fo, GC_finalize_now);
612 GC_finalize_now = curr_fo;
613 /* unhide object pointer so any future collections will */
614 /* see it. */
615 curr_fo -> fo_hidden_base =
616 (word) REVEAL_POINTER(curr_fo -> fo_hidden_base);
617 GC_words_finalized +=
618 ALIGNED_WORDS(curr_fo -> fo_object_size)
619 + ALIGNED_WORDS(sizeof(struct finalizable_object));
620 GC_ASSERT(GC_is_marked(GC_base((ptr_t)curr_fo)));
621 curr_fo = next_fo;
622 } else {
623 prev_fo = curr_fo;
624 curr_fo = fo_next(curr_fo);
625 }
626 }
627 }
628
629 if (GC_java_finalization) {
630 /* make sure we mark everything reachable from objects finalized
631 using the no_order mark_proc */
632 for (curr_fo = GC_finalize_now;
633 curr_fo != NULL; curr_fo = fo_next(curr_fo)) {
634 real_ptr = (ptr_t)curr_fo -> fo_hidden_base;
635 if (!GC_is_marked(real_ptr)) {
636 if (curr_fo -> fo_mark_proc == GC_null_finalize_mark_proc) {
637 GC_MARK_FO(real_ptr, GC_normal_finalize_mark_proc);
638 }
639 GC_set_mark_bit(real_ptr);
640 }
641 }
642 }
643
644 /* Remove dangling disappearing links. */
645 for (i = 0; i < dl_size; i++) {
646 curr_dl = dl_head[i];
647 prev_dl = 0;
648 while (curr_dl != 0) {
649 real_link = GC_base((ptr_t)REVEAL_POINTER(curr_dl -> dl_hidden_link));
650 if (real_link != 0 && !GC_is_marked(real_link)) {
651 next_dl = dl_next(curr_dl);
652 if (prev_dl == 0) {
653 dl_head[i] = next_dl;
654 } else {
655 dl_set_next(prev_dl, next_dl);
656 }
657 GC_clear_mark_bit((ptr_t)curr_dl);
658 GC_dl_entries--;
659 curr_dl = next_dl;
660 } else {
661 prev_dl = curr_dl;
662 curr_dl = dl_next(curr_dl);
663 }
664 }
665 }
666}
667
668#ifndef JAVA_FINALIZATION_NOT_NEEDED
669
670/* Enqueue all remaining finalizers to be run - Assumes lock is
671 * held, and signals are disabled */
672void GC_enqueue_all_finalizers()
673{
674 struct finalizable_object * curr_fo, * prev_fo, * next_fo;
675 ptr_t real_ptr;
676 register int i;
677 int fo_size;
678
679 fo_size = (log_fo_table_size == -1 ) ? 0 : (1 << log_fo_table_size);
680 GC_words_finalized = 0;
681 for (i = 0; i < fo_size; i++) {
682 curr_fo = fo_head[i];
683 prev_fo = 0;
684 while (curr_fo != 0) {
685 real_ptr = (ptr_t)REVEAL_POINTER(curr_fo -> fo_hidden_base);
686 GC_MARK_FO(real_ptr, GC_normal_finalize_mark_proc);
687 GC_set_mark_bit(real_ptr);
688
689 /* Delete from hash table */
690 next_fo = fo_next(curr_fo);
691 if (prev_fo == 0) {
692 fo_head[i] = next_fo;
693 } else {
694 fo_set_next(prev_fo, next_fo);
695 }
696 GC_fo_entries--;
697
698 /* Add to list of objects awaiting finalization. */
699 fo_set_next(curr_fo, GC_finalize_now);
700 GC_finalize_now = curr_fo;
701
702 /* unhide object pointer so any future collections will */
703 /* see it. */
704 curr_fo -> fo_hidden_base =
705 (word) REVEAL_POINTER(curr_fo -> fo_hidden_base);
706
707 GC_words_finalized +=
708 ALIGNED_WORDS(curr_fo -> fo_object_size)
709 + ALIGNED_WORDS(sizeof(struct finalizable_object));
710 curr_fo = next_fo;
711 }
712 }
713
714 return;
715}
716
717/* Invoke all remaining finalizers that haven't yet been run.
718 * This is needed for strict compliance with the Java standard,
719 * which can make the runtime guarantee that all finalizers are run.
720 * Unfortunately, the Java standard implies we have to keep running
721 * finalizers until there are no more left, a potential infinite loop.
722 * YUCK.
723 * Note that this is even more dangerous than the usual Java
724 * finalizers, in that objects reachable from static variables
725 * may have been finalized when these finalizers are run.
726 * Finalizers run at this point must be prepared to deal with a
727 * mostly broken world.
728 * This routine is externally callable, so is called without
729 * the allocation lock.
730 */
731GC_API void GC_finalize_all()
732{
733 DCL_LOCK_STATE;
734
735 DISABLE_SIGNALS();
736 LOCK();
737 while (GC_fo_entries > 0) {
738 GC_enqueue_all_finalizers();
739 UNLOCK();
740 ENABLE_SIGNALS();
741 GC_INVOKE_FINALIZERS();
742 DISABLE_SIGNALS();
743 LOCK();
744 }
745 UNLOCK();
746 ENABLE_SIGNALS();
747}
748#endif
749
750/* Returns true if it is worth calling GC_invoke_finalizers. (Useful if */
751/* finalizers can only be called from some kind of `safe state' and */
752/* getting into that safe state is expensive.) */
753int GC_should_invoke_finalizers GC_PROTO((void))
754{
755 return GC_finalize_now != 0;
756}
757
758/* Invoke finalizers for all objects that are ready to be finalized. */
759/* Should be called without allocation lock. */
760int GC_invoke_finalizers()
761{
762 register struct finalizable_object * curr_fo;
763 register int count = 0;
764 DCL_LOCK_STATE;
765
766 while (GC_finalize_now != 0) {
767# ifdef THREADS
768 DISABLE_SIGNALS();
769 LOCK();
770# endif
771 curr_fo = GC_finalize_now;
772# ifdef THREADS
773 if (curr_fo != 0) GC_finalize_now = fo_next(curr_fo);
774 UNLOCK();
775 ENABLE_SIGNALS();
776 if (curr_fo == 0) break;
777# else
778 GC_finalize_now = fo_next(curr_fo);
779# endif
780 fo_set_next(curr_fo, 0);
781 (*(curr_fo -> fo_fn))((ptr_t)(curr_fo -> fo_hidden_base),
782 curr_fo -> fo_client_data);
783 curr_fo -> fo_client_data = 0;
784 ++count;
785# ifdef UNDEFINED
786 /* This is probably a bad idea. It throws off accounting if */
787 /* nearly all objects are finalizable. O.w. it shouldn't */
788 /* matter. */
789 GC_free((GC_PTR)curr_fo);
790# endif
791 }
792 return count;
793}
794
795void (* GC_finalizer_notifier)() = (void (*) GC_PROTO((void)))0;
796
797static GC_word last_finalizer_notification = 0;
798
799void GC_notify_or_invoke_finalizers GC_PROTO((void))
800{
801 if (GC_finalize_now == 0) return;
802 if (!GC_finalize_on_demand) {
803 (void) GC_invoke_finalizers();
804 GC_ASSERT(GC_finalize_now == 0);
805 return;
806 }
807 if (GC_finalizer_notifier != (void (*) GC_PROTO((void)))0
808 && last_finalizer_notification != GC_gc_no) {
809 last_finalizer_notification = GC_gc_no;
810 GC_finalizer_notifier();
811 }
812}
813
814# ifdef __STDC__
815 GC_PTR GC_call_with_alloc_lock(GC_fn_type fn,
816 GC_PTR client_data)
817# else
818 GC_PTR GC_call_with_alloc_lock(fn, client_data)
819 GC_fn_type fn;
820 GC_PTR client_data;
821# endif
822{
823 GC_PTR result;
824 DCL_LOCK_STATE;
825
826# ifdef THREADS
827 DISABLE_SIGNALS();
828 LOCK();
829 SET_LOCK_HOLDER();
830# endif
831 result = (*fn)(client_data);
832# ifdef THREADS
833# ifndef GC_ASSERTIONS
834 UNSET_LOCK_HOLDER();
835# endif /* o.w. UNLOCK() does it implicitly */
836 UNLOCK();
837 ENABLE_SIGNALS();
838# endif
839 return(result);
840}
841
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