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;
22 int GC_finalize_on_demand
= 0;
25 # ifdef JAVA_FINALIZATION
26 int GC_java_finalization
= 1;
28 int GC_java_finalization
= 0;
31 /* Type of mark procedure used for marking from finalizable object. */
32 /* This procedure normally does not mark the object, only its */
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)))) \
39 #define HASH2(addr,log_size) HASH3(addr, 1 << log_size, log_size)
41 struct hash_chain_entry
{
43 struct hash_chain_entry
* next
;
46 unsigned GC_finalization_failures
= 0;
47 /* Number of finalization requests that failed for lack of memory. */
49 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 */
60 struct disappearing_link
**head
;
66 static int GC_register_disappearing_link_inner(struct dl_hashtbl_s
*dl_hashtbl
, GC_PTR
* link
, GC_PTR obj
);
67 static int GC_unregister_disappearing_link_inner(struct dl_hashtbl_s
*dl_hashtbl
, GC_PTR
* link
);
69 static struct dl_hashtbl_s GC_dl_hashtbl
= {
70 /* head */ NULL
, /* log_size */ -1, /* entries */ 0 };
72 static struct dl_hashtbl_s GC_ll_hashtbl
= { NULL
, -1, 0 };
75 static struct finalizable_object
{
76 struct hash_chain_entry prolog
;
77 # define fo_hidden_base prolog.hidden_key
78 /* Pointer to object base. */
79 /* No longer hidden once object */
80 /* is on finalize_now queue. */
81 # define fo_next(x) (struct finalizable_object *)((x) -> prolog.next)
82 # define fo_set_next(x,y) (x) -> prolog.next = (struct hash_chain_entry *)(y)
83 GC_finalization_proc fo_fn
; /* Finalizer. */
85 word fo_object_size
; /* In bytes. */
86 finalization_mark_proc
* fo_mark_proc
; /* Mark-through procedure */
89 struct finalizable_object
* GC_finalize_now
= 0;
90 /* LIst of objects that should be finalized now. */
92 static signed_word log_fo_table_size
= -1;
94 word GC_fo_entries
= 0;
96 void GC_push_finalizer_structures
GC_PROTO((void))
98 GC_push_all((ptr_t
)(&GC_ll_hashtbl
.head
),
99 (ptr_t
)(&GC_ll_hashtbl
.head
) + sizeof(word
));
100 GC_push_all((ptr_t
)(&GC_dl_hashtbl
.head
),
101 (ptr_t
)(&GC_dl_hashtbl
.head
) + sizeof(word
));
102 GC_push_all((ptr_t
)(&fo_head
), (ptr_t
)(&fo_head
) + sizeof(word
));
103 GC_push_all((ptr_t
)(&GC_finalize_now
),
104 (ptr_t
)(&GC_finalize_now
) + sizeof(word
));
107 /* Double the size of a hash table. *size_ptr is the log of its current */
108 /* size. May be a noop. */
109 /* *table is a pointer to an array of hash headers. If we succeed, we */
110 /* update both *table and *log_size_ptr. */
111 /* Lock is held. Signals are disabled. */
112 void GC_grow_table(table
, log_size_ptr
)
113 struct hash_chain_entry
***table
;
114 signed_word
* log_size_ptr
;
117 register struct hash_chain_entry
*p
;
118 int log_old_size
= *log_size_ptr
;
119 register int log_new_size
= log_old_size
+ 1;
120 word old_size
= ((log_old_size
== -1)? 0: (1 << log_old_size
));
121 register word new_size
= 1 << log_new_size
;
122 struct hash_chain_entry
**new_table
= (struct hash_chain_entry
**)
123 GC_INTERNAL_MALLOC_IGNORE_OFF_PAGE(
124 (size_t)new_size
* sizeof(struct hash_chain_entry
*), NORMAL
);
126 if (new_table
== 0) {
128 ABORT("Insufficient space for initial table allocation");
133 for (i
= 0; i
< old_size
; i
++) {
136 register ptr_t real_key
= (ptr_t
)REVEAL_POINTER(p
-> hidden_key
);
137 register struct hash_chain_entry
*next
= p
-> next
;
138 register int new_hash
= HASH3(real_key
, new_size
, log_new_size
);
140 p
-> next
= new_table
[new_hash
];
141 new_table
[new_hash
] = p
;
145 *log_size_ptr
= log_new_size
;
149 # if defined(__STDC__) || defined(__cplusplus)
150 int GC_register_disappearing_link(GC_PTR
* link
)
152 int GC_register_disappearing_link(link
)
158 base
= (ptr_t
)GC_base((GC_PTR
)link
);
160 ABORT("Bad arg to GC_register_disappearing_link");
161 return(GC_general_register_disappearing_link(link
, base
));
164 # if defined(__STDC__) || defined(__cplusplus)
165 int GC_general_register_disappearing_link(GC_PTR
* link
,
168 int GC_general_register_disappearing_link(link
, obj
)
173 return GC_register_disappearing_link_inner(&GC_dl_hashtbl
, link
, obj
);
176 # if defined(__STDC__) || defined(__cplusplus)
177 static int GC_register_disappearing_link_inner(struct dl_hashtbl_s
*dl_hashtbl
, GC_PTR
* link
,
180 static int GC_register_disappearing_link_inner(dl_hashtbl
, link
, obj
)
181 struct dl_hashtbl_s
*dl_hashtbl
186 struct disappearing_link
*curr_dl
;
188 struct disappearing_link
* new_dl
;
191 if ((word
)link
& (ALIGNMENT
-1))
192 ABORT("Bad arg to GC_general_register_disappearing_link");
197 if (dl_hashtbl
-> log_size
== -1
198 || dl_hashtbl
-> entries
> ((word
)1 << dl_hashtbl
-> log_size
)) {
202 GC_grow_table((struct hash_chain_entry
***)(&dl_hashtbl
-> head
),
203 &dl_hashtbl
-> log_size
);
205 if (GC_print_stats
) {
206 GC_printf1("Grew dl table to %lu entries\n",
207 (unsigned long)(1 << dl_hashtbl
-> log_size
));
214 index
= HASH2(link
, dl_hashtbl
-> log_size
);
215 curr_dl
= dl_hashtbl
-> head
[index
];
216 for (curr_dl
= dl_hashtbl
-> head
[index
]; curr_dl
!= 0; curr_dl
= dl_next(curr_dl
)) {
217 if (curr_dl
-> dl_hidden_link
== HIDE_POINTER(link
)) {
218 curr_dl
-> dl_hidden_obj
= HIDE_POINTER(obj
);
226 new_dl
= (struct disappearing_link
*)
227 GC_INTERNAL_MALLOC(sizeof(struct disappearing_link
),NORMAL
);
233 new_dl
= (struct disappearing_link
*)
234 GC_oom_fn(sizeof(struct disappearing_link
));
236 GC_finalization_failures
++;
239 /* It's not likely we'll make it here, but ... */
245 new_dl
-> dl_hidden_obj
= HIDE_POINTER(obj
);
246 new_dl
-> dl_hidden_link
= HIDE_POINTER(link
);
247 dl_set_next(new_dl
, dl_hashtbl
-> head
[index
]);
248 dl_hashtbl
-> head
[index
] = new_dl
;
249 dl_hashtbl
-> entries
++;
257 # if defined(__STDC__) || defined(__cplusplus)
258 int GC_unregister_disappearing_link(GC_PTR
* link
)
260 int GC_unregister_disappearing_link(link
)
264 return GC_unregister_disappearing_link_inner(&GC_dl_hashtbl
, link
);
267 # if defined(__STDC__) || defined(__cplusplus)
268 static int GC_unregister_disappearing_link_inner(struct dl_hashtbl_s
*dl_hashtbl
, GC_PTR
* link
)
270 static int GC_unregister_disappearing_link_inner(dl_hashtbl
, link
)
271 struct dl_hashtbl_s
*dl_hashtbl
;
275 struct disappearing_link
*curr_dl
, *prev_dl
;
281 index
= HASH2(link
, dl_hashtbl
->log_size
);
282 if (((unsigned long)link
& (ALIGNMENT
-1))) goto out
;
283 prev_dl
= 0; curr_dl
= dl_hashtbl
-> head
[index
];
284 while (curr_dl
!= 0) {
285 if (curr_dl
-> dl_hidden_link
== HIDE_POINTER(link
)) {
287 dl_hashtbl
-> head
[index
] = dl_next(curr_dl
);
289 dl_set_next(prev_dl
, dl_next(curr_dl
));
291 dl_hashtbl
-> entries
--;
295 dl_set_next(curr_dl
, 0);
297 GC_free((GC_PTR
)curr_dl
);
302 curr_dl
= dl_next(curr_dl
);
310 /* toggleref support */
313 GC_hidden_pointer weak_ref
;
316 static int (*GC_toggleref_callback
) (GC_PTR obj
);
317 static GCToggleRef
*GC_toggleref_array
;
318 static int GC_toggleref_array_size
;
319 static int GC_toggleref_array_capacity
;
323 GC_process_togglerefs (void)
326 int toggle_ref_counts
[3] = { 0, 0, 0 };
328 for (i
= w
= 0; i
< GC_toggleref_array_size
; ++i
) {
330 GCToggleRef r
= GC_toggleref_array
[i
];
337 obj
= REVEAL_POINTER (r
.weak_ref
);
341 res
= GC_toggleref_callback (obj
);
342 ++toggle_ref_counts
[res
];
347 GC_toggleref_array
[w
].strong_ref
= obj
;
348 GC_toggleref_array
[w
].weak_ref
= (GC_hidden_pointer
)NULL
;
352 GC_toggleref_array
[w
].strong_ref
= NULL
;
353 GC_toggleref_array
[w
].weak_ref
= HIDE_POINTER (obj
);
357 ABORT("Invalid callback result");
361 for (i
= w
; i
< GC_toggleref_array_size
; ++i
) {
362 GC_toggleref_array
[w
].strong_ref
= NULL
;
363 GC_toggleref_array
[w
].weak_ref
= (GC_hidden_pointer
)NULL
;
366 GC_toggleref_array_size
= w
;
370 static void push_and_mark_object (GC_PTR p
)
374 PUSH_OBJ((word
*)p
, hhdr
, GC_mark_stack_top
,
375 &(GC_mark_stack
[GC_mark_stack_size
]));
377 while (!GC_mark_stack_empty()) MARK_FROM_MARK_STACK();
379 if (GC_mark_state
!= MS_NONE
)
380 while (!GC_mark_some((ptr_t
)0)) {}
383 static void GC_mark_togglerefs ()
386 if (!GC_toggleref_array
)
389 GC_set_mark_bit ((GC_PTR
)GC_toggleref_array
);
390 for (i
= 0; i
< GC_toggleref_array_size
; ++i
) {
391 if (GC_toggleref_array
[i
].strong_ref
) {
392 GC_PTR object
= GC_toggleref_array
[i
].strong_ref
;
394 push_and_mark_object (object
);
399 static void GC_clear_togglerefs ()
402 for (i
= 0; i
< GC_toggleref_array_size
; ++i
) {
403 if (GC_toggleref_array
[i
].weak_ref
) {
404 GC_PTR object
= REVEAL_POINTER (GC_toggleref_array
[i
].weak_ref
);
406 if (!GC_is_marked (object
)) {
407 GC_toggleref_array
[i
].weak_ref
= (GC_hidden_pointer
)NULL
; /* We defer compaction to only happen on the callback step. */
409 /*No need to copy, boehm is non-moving */
417 void GC_toggleref_register_callback(int (*proccess_toggleref
) (GC_PTR obj
))
419 GC_toggleref_callback
= proccess_toggleref
;
423 ensure_toggleref_capacity (int capacity
)
425 if (!GC_toggleref_array
) {
426 GC_toggleref_array_capacity
= 32;
427 GC_toggleref_array
= (GCToggleRef
*) GC_INTERNAL_MALLOC_IGNORE_OFF_PAGE (GC_toggleref_array_capacity
* sizeof (GCToggleRef
), NORMAL
);
429 if (GC_toggleref_array_size
+ capacity
>= GC_toggleref_array_capacity
) {
431 int old_capacity
= GC_toggleref_array_capacity
;
432 while (GC_toggleref_array_capacity
< GC_toggleref_array_size
+ capacity
)
433 GC_toggleref_array_capacity
*= 2;
435 tmp
= (GCToggleRef
*) GC_INTERNAL_MALLOC_IGNORE_OFF_PAGE (GC_toggleref_array_capacity
* sizeof (GCToggleRef
), NORMAL
);
436 memcpy (tmp
, GC_toggleref_array
, GC_toggleref_array_size
* sizeof (GCToggleRef
));
437 GC_INTERNAL_FREE (GC_toggleref_array
);
438 GC_toggleref_array
= tmp
;
443 GC_toggleref_add (GC_PTR object
, int strong_ref
)
451 if (!GC_toggleref_callback
)
454 ensure_toggleref_capacity (1);
455 GC_toggleref_array
[GC_toggleref_array_size
].strong_ref
= strong_ref
? object
: NULL
;
456 GC_toggleref_array
[GC_toggleref_array_size
].weak_ref
= strong_ref
? (GC_hidden_pointer
)NULL
: HIDE_POINTER (object
);
457 ++GC_toggleref_array_size
;
468 # if defined(__STDC__) || defined(__cplusplus)
469 int GC_register_long_link(GC_PTR
* link
, GC_PTR obj
)
471 int GC_register_long_link(link
, obj
)
476 return GC_register_disappearing_link_inner(&GC_ll_hashtbl
, link
, obj
);
479 # if defined(__STDC__) || defined(__cplusplus)
480 int GC_unregister_long_link(GC_PTR
* link
)
482 int GC_unregister_long_link(link
)
486 return GC_unregister_disappearing_link_inner(&GC_ll_hashtbl
, link
);
489 /* Possible finalization_marker procedures. Note that mark stack */
490 /* overflow is handled by the caller, and is not a disaster. */
491 GC_API
void GC_normal_finalize_mark_proc(p
)
496 PUSH_OBJ((word
*)p
, hhdr
, GC_mark_stack_top
,
497 &(GC_mark_stack
[GC_mark_stack_size
]));
500 /* This only pays very partial attention to the mark descriptor. */
501 /* It does the right thing for normal and atomic objects, and treats */
502 /* most others as normal. */
503 GC_API
void GC_ignore_self_finalize_mark_proc(p
)
507 word descr
= hhdr
-> hb_descr
;
510 ptr_t target_limit
= p
+ WORDS_TO_BYTES(hhdr
-> hb_sz
) - 1;
512 if ((descr
& GC_DS_TAGS
) == GC_DS_LENGTH
) {
513 scan_limit
= p
+ descr
- sizeof(word
);
515 scan_limit
= target_limit
+ 1 - sizeof(word
);
517 for (q
= p
; q
<= scan_limit
; q
+= ALIGNMENT
) {
519 if (r
< p
|| r
> target_limit
) {
520 GC_PUSH_ONE_HEAP((word
)r
, q
);
526 GC_API
void GC_null_finalize_mark_proc(p
)
533 /* Register a finalization function. See gc.h for details. */
534 /* in the nonthreads case, we try to avoid disabling signals, */
535 /* since it can be expensive. Threads packages typically */
536 /* make it cheaper. */
537 /* The last parameter is a procedure that determines */
538 /* marking for finalization ordering. Any objects marked */
539 /* by that procedure will be guaranteed to not have been */
540 /* finalized when this finalizer is invoked. */
541 GC_API
void GC_register_finalizer_inner(obj
, fn
, cd
, ofn
, ocd
, mp
)
543 GC_finalization_proc fn
;
545 GC_finalization_proc
* ofn
;
547 finalization_mark_proc
* mp
;
550 struct finalizable_object
* curr_fo
, * prev_fo
;
552 struct finalizable_object
*new_fo
;
560 if (log_fo_table_size
== -1
561 || GC_fo_entries
> ((word
)1 << log_fo_table_size
)) {
565 GC_grow_table((struct hash_chain_entry
***)(&fo_head
),
568 if (GC_print_stats
) {
569 GC_printf1("Grew fo table to %lu entries\n",
570 (unsigned long)(1 << log_fo_table_size
));
577 /* in the THREADS case signals are disabled and we hold allocation */
578 /* lock; otherwise neither is true. Proceed carefully. */
580 index
= HASH2(base
, log_fo_table_size
);
581 prev_fo
= 0; curr_fo
= fo_head
[index
];
582 while (curr_fo
!= 0) {
583 if (curr_fo
-> fo_hidden_base
== HIDE_POINTER(base
)) {
584 /* Interruption by a signal in the middle of this */
585 /* should be safe. The client may see only *ocd */
586 /* updated, but we'll declare that to be his */
588 if (ocd
) *ocd
= (GC_PTR
) curr_fo
-> fo_client_data
;
589 if (ofn
) *ofn
= curr_fo
-> fo_fn
;
590 /* Delete the structure for base. */
592 fo_head
[index
] = fo_next(curr_fo
);
594 fo_set_next(prev_fo
, fo_next(curr_fo
));
598 /* May not happen if we get a signal. But a high */
599 /* estimate will only make the table larger than */
601 # if !defined(THREADS) && !defined(DBG_HDRS_ALL)
602 GC_free((GC_PTR
)curr_fo
);
605 curr_fo
-> fo_fn
= fn
;
606 curr_fo
-> fo_client_data
= (ptr_t
)cd
;
607 curr_fo
-> fo_mark_proc
= mp
;
608 /* Reinsert it. We deleted it first to maintain */
609 /* consistency in the event of a signal. */
611 fo_head
[index
] = curr_fo
;
613 fo_set_next(prev_fo
, curr_fo
);
623 curr_fo
= fo_next(curr_fo
);
636 /* We won't collect it, hence finalizer wouldn't be run. */
643 new_fo
= (struct finalizable_object
*)
644 GC_INTERNAL_MALLOC(sizeof(struct finalizable_object
),NORMAL
);
650 new_fo
= (struct finalizable_object
*)
651 GC_oom_fn(sizeof(struct finalizable_object
));
653 GC_finalization_failures
++;
656 /* It's not likely we'll make it here, but ... */
662 new_fo
-> fo_hidden_base
= (word
)HIDE_POINTER(base
);
663 new_fo
-> fo_fn
= fn
;
664 new_fo
-> fo_client_data
= (ptr_t
)cd
;
665 new_fo
-> fo_object_size
= hhdr
-> hb_sz
;
666 new_fo
-> fo_mark_proc
= mp
;
667 fo_set_next(new_fo
, fo_head
[index
]);
669 fo_head
[index
] = new_fo
;
676 # if defined(__STDC__)
677 void GC_register_finalizer(void * obj
,
678 GC_finalization_proc fn
, void * cd
,
679 GC_finalization_proc
*ofn
, void ** ocd
)
681 void GC_register_finalizer(obj
, fn
, cd
, ofn
, ocd
)
683 GC_finalization_proc fn
;
685 GC_finalization_proc
* ofn
;
689 GC_register_finalizer_inner(obj
, fn
, cd
, ofn
,
690 ocd
, GC_normal_finalize_mark_proc
);
693 # if defined(__STDC__)
694 void GC_register_finalizer_ignore_self(void * obj
,
695 GC_finalization_proc fn
, void * cd
,
696 GC_finalization_proc
*ofn
, void ** ocd
)
698 void GC_register_finalizer_ignore_self(obj
, fn
, cd
, ofn
, ocd
)
700 GC_finalization_proc fn
;
702 GC_finalization_proc
* ofn
;
706 GC_register_finalizer_inner(obj
, fn
, cd
, ofn
,
707 ocd
, GC_ignore_self_finalize_mark_proc
);
710 # if defined(__STDC__)
711 void GC_register_finalizer_no_order(void * obj
,
712 GC_finalization_proc fn
, void * cd
,
713 GC_finalization_proc
*ofn
, void ** ocd
)
715 void GC_register_finalizer_no_order(obj
, fn
, cd
, ofn
, ocd
)
717 GC_finalization_proc fn
;
719 GC_finalization_proc
* ofn
;
723 GC_register_finalizer_inner(obj
, fn
, cd
, ofn
,
724 ocd
, GC_null_finalize_mark_proc
);
729 static void GC_dump_finalization_links(struct dl_hashtbl_s
*dl_hashtbl
)
731 struct disappearing_link
*curr_dl
;
732 ptr_t real_ptr
, real_link
;
733 size_t dl_size
= dl_hashtbl
->log_size
== -1 ? 0 :
734 1 << dl_hashtbl
->log_size
;
737 for (i
= 0; i
< dl_size
; i
++) {
738 for (curr_dl
= dl_hashtbl
-> head
[i
]; curr_dl
!= 0;
739 curr_dl
= dl_next(curr_dl
)) {
740 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_dl
-> dl_hidden_obj
);
741 real_link
= (ptr_t
)REVEAL_POINTER(curr_dl
-> dl_hidden_link
);
742 GC_printf2("Object: %lx, link: %lx\n", real_ptr
, real_link
);
747 void GC_dump_finalization()
749 struct finalizable_object
* curr_fo
;
751 int fo_size
= (log_fo_table_size
== -1 ) ? 0 : (1 << log_fo_table_size
);
754 GC_printf0("Disappearing (short) links:\n");
755 GC_dump_finalization_links(&GC_dl_hashtbl
);
756 GC_printf0("Disappearing long links:\n");
757 GC_dump_finalization_links(&GC_ll_hashtbl
);
759 GC_printf0("Finalizers:\n");
760 for (i
= 0; i
< fo_size
; i
++) {
761 for (curr_fo
= fo_head
[i
]; curr_fo
!= 0; curr_fo
= fo_next(curr_fo
)) {
762 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
763 GC_printf1("Finalizable object: 0x%lx\n", real_ptr
);
769 static void GC_make_disappearing_links_disappear(struct dl_hashtbl_s
*dl_hashtbl
)
771 struct disappearing_link
* curr_dl
, * prev_dl
, * next_dl
;
772 ptr_t real_ptr
, real_link
;
774 int dl_size
= (dl_hashtbl
-> log_size
== -1 ) ? 0 : (1 << dl_hashtbl
-> log_size
);
776 for (i
= 0; i
< dl_size
; i
++) {
777 curr_dl
= dl_hashtbl
-> head
[i
];
779 while (curr_dl
!= 0) {
780 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_dl
-> dl_hidden_obj
);
781 real_link
= (ptr_t
)REVEAL_POINTER(curr_dl
-> dl_hidden_link
);
782 if (!GC_is_marked(real_ptr
)) {
783 *(word
*)real_link
= 0;
784 next_dl
= dl_next(curr_dl
);
786 dl_hashtbl
-> head
[i
] = next_dl
;
788 dl_set_next(prev_dl
, next_dl
);
790 GC_clear_mark_bit((ptr_t
)curr_dl
);
791 dl_hashtbl
-> entries
--;
795 curr_dl
= dl_next(curr_dl
);
801 static void GC_remove_dangling_disappearing_links(struct dl_hashtbl_s
*dl_hashtbl
)
803 struct disappearing_link
* curr_dl
, * prev_dl
, * next_dl
;
804 ptr_t real_ptr
, real_link
;
806 int dl_size
= (dl_hashtbl
-> log_size
== -1 ) ? 0 : (1 << dl_hashtbl
-> log_size
);
808 for (i
= 0; i
< dl_size
; i
++) {
809 curr_dl
= dl_hashtbl
-> head
[i
];
811 while (curr_dl
!= 0) {
812 real_link
= GC_base((ptr_t
)REVEAL_POINTER(curr_dl
-> dl_hidden_link
));
813 if (real_link
!= 0 && !GC_is_marked(real_link
)) {
814 next_dl
= dl_next(curr_dl
);
816 dl_hashtbl
-> head
[i
] = next_dl
;
818 dl_set_next(prev_dl
, next_dl
);
820 GC_clear_mark_bit((ptr_t
)curr_dl
);
821 dl_hashtbl
-> entries
--;
825 curr_dl
= dl_next(curr_dl
);
831 /* Called with world stopped. Cause disappearing links to disappear, */
832 /* and invoke finalizers. */
835 struct finalizable_object
* curr_fo
, * prev_fo
, * next_fo
;
838 int fo_size
= (log_fo_table_size
== -1 ) ? 0 : (1 << log_fo_table_size
);
840 GC_mark_togglerefs();
842 /* Make non-tracking disappearing links disappear */
843 GC_make_disappearing_links_disappear(&GC_dl_hashtbl
);
845 /* Mark all objects reachable via chains of 1 or more pointers */
846 /* from finalizable objects. */
847 GC_ASSERT(GC_mark_state
== MS_NONE
);
848 for (i
= 0; i
< fo_size
; i
++) {
849 for (curr_fo
= fo_head
[i
]; curr_fo
!= 0; curr_fo
= fo_next(curr_fo
)) {
850 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
851 if (!GC_is_marked(real_ptr
)) {
852 GC_MARKED_FOR_FINALIZATION(real_ptr
);
853 GC_MARK_FO(real_ptr
, curr_fo
-> fo_mark_proc
);
854 if (GC_is_marked(real_ptr
)) {
855 WARN("Finalization cycle involving %lx\n", real_ptr
);
860 /* Enqueue for finalization all objects that are still */
862 GC_words_finalized
= 0;
863 for (i
= 0; i
< fo_size
; i
++) {
864 curr_fo
= fo_head
[i
];
866 while (curr_fo
!= 0) {
867 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
868 if (!GC_is_marked(real_ptr
)) {
869 if (!GC_java_finalization
) {
870 GC_set_mark_bit(real_ptr
);
872 /* Delete from hash table */
873 next_fo
= fo_next(curr_fo
);
875 fo_head
[i
] = next_fo
;
877 fo_set_next(prev_fo
, next_fo
);
880 /* Add to list of objects awaiting finalization. */
881 fo_set_next(curr_fo
, GC_finalize_now
);
882 GC_finalize_now
= curr_fo
;
883 /* unhide object pointer so any future collections will */
885 curr_fo
-> fo_hidden_base
=
886 (word
) REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
887 GC_words_finalized
+=
888 ALIGNED_WORDS(curr_fo
-> fo_object_size
)
889 + ALIGNED_WORDS(sizeof(struct finalizable_object
));
890 GC_ASSERT(GC_is_marked(GC_base((ptr_t
)curr_fo
)));
894 curr_fo
= fo_next(curr_fo
);
899 if (GC_java_finalization
) {
900 /* make sure we mark everything reachable from objects finalized
901 using the no_order mark_proc */
902 for (curr_fo
= GC_finalize_now
;
903 curr_fo
!= NULL
; curr_fo
= fo_next(curr_fo
)) {
904 real_ptr
= (ptr_t
)curr_fo
-> fo_hidden_base
;
905 if (!GC_is_marked(real_ptr
)) {
906 if (curr_fo
-> fo_mark_proc
== GC_null_finalize_mark_proc
) {
907 GC_MARK_FO(real_ptr
, GC_normal_finalize_mark_proc
);
909 GC_set_mark_bit(real_ptr
);
914 /* Remove dangling disappearing links. */
915 GC_remove_dangling_disappearing_links(&GC_dl_hashtbl
);
917 GC_clear_togglerefs ();
919 /* Make long links disappear and remove dangling ones. */
920 GC_make_disappearing_links_disappear(&GC_ll_hashtbl
);
921 GC_remove_dangling_disappearing_links(&GC_ll_hashtbl
);
924 #ifndef JAVA_FINALIZATION_NOT_NEEDED
926 /* Enqueue all remaining finalizers to be run - Assumes lock is
927 * held, and signals are disabled */
928 void GC_enqueue_all_finalizers()
930 struct finalizable_object
* curr_fo
, * prev_fo
, * next_fo
;
935 fo_size
= (log_fo_table_size
== -1 ) ? 0 : (1 << log_fo_table_size
);
936 GC_words_finalized
= 0;
937 for (i
= 0; i
< fo_size
; i
++) {
938 curr_fo
= fo_head
[i
];
940 while (curr_fo
!= 0) {
941 real_ptr
= (ptr_t
)REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
942 GC_MARK_FO(real_ptr
, GC_normal_finalize_mark_proc
);
943 GC_set_mark_bit(real_ptr
);
945 /* Delete from hash table */
946 next_fo
= fo_next(curr_fo
);
948 fo_head
[i
] = next_fo
;
950 fo_set_next(prev_fo
, next_fo
);
954 /* Add to list of objects awaiting finalization. */
955 fo_set_next(curr_fo
, GC_finalize_now
);
956 GC_finalize_now
= curr_fo
;
958 /* unhide object pointer so any future collections will */
960 curr_fo
-> fo_hidden_base
=
961 (word
) REVEAL_POINTER(curr_fo
-> fo_hidden_base
);
963 GC_words_finalized
+=
964 ALIGNED_WORDS(curr_fo
-> fo_object_size
)
965 + ALIGNED_WORDS(sizeof(struct finalizable_object
));
973 /* Invoke all remaining finalizers that haven't yet been run.
974 * This is needed for strict compliance with the Java standard,
975 * which can make the runtime guarantee that all finalizers are run.
976 * Unfortunately, the Java standard implies we have to keep running
977 * finalizers until there are no more left, a potential infinite loop.
979 * Note that this is even more dangerous than the usual Java
980 * finalizers, in that objects reachable from static variables
981 * may have been finalized when these finalizers are run.
982 * Finalizers run at this point must be prepared to deal with a
983 * mostly broken world.
984 * This routine is externally callable, so is called without
985 * the allocation lock.
987 GC_API
void GC_finalize_all()
993 while (GC_fo_entries
> 0) {
994 GC_enqueue_all_finalizers();
997 GC_INVOKE_FINALIZERS();
1006 /* Returns true if it is worth calling GC_invoke_finalizers. (Useful if */
1007 /* finalizers can only be called from some kind of `safe state' and */
1008 /* getting into that safe state is expensive.) */
1009 int GC_should_invoke_finalizers
GC_PROTO((void))
1011 return GC_finalize_now
!= 0;
1014 /* Invoke finalizers for all objects that are ready to be finalized. */
1015 /* Should be called without allocation lock. */
1016 int GC_invoke_finalizers()
1018 struct finalizable_object
* curr_fo
;
1020 word mem_freed_before
;
1023 while (GC_finalize_now
!= 0) {
1029 mem_freed_before
= GC_mem_freed
;
1031 curr_fo
= GC_finalize_now
;
1033 if (curr_fo
!= 0) GC_finalize_now
= fo_next(curr_fo
);
1036 if (curr_fo
== 0) break;
1038 GC_finalize_now
= fo_next(curr_fo
);
1040 fo_set_next(curr_fo
, 0);
1041 (*(curr_fo
-> fo_fn
))((ptr_t
)(curr_fo
-> fo_hidden_base
),
1042 curr_fo
-> fo_client_data
);
1043 curr_fo
-> fo_client_data
= 0;
1046 /* This is probably a bad idea. It throws off accounting if */
1047 /* nearly all objects are finalizable. O.w. it shouldn't */
1049 GC_free((GC_PTR
)curr_fo
);
1052 if (count
!= 0 && mem_freed_before
!= GC_mem_freed
) {
1054 GC_finalizer_mem_freed
+= (GC_mem_freed
- mem_freed_before
);
1060 void (* GC_finalizer_notifier
)() = (void (*) GC_PROTO((void)))0;
1062 static GC_word last_finalizer_notification
= 0;
1064 void GC_notify_or_invoke_finalizers
GC_PROTO((void))
1066 /* This is a convenient place to generate backtraces if appropriate, */
1067 /* since that code is not callable with the allocation lock. */
1068 # if defined(KEEP_BACK_PTRS) || defined(MAKE_BACK_GRAPH)
1069 static word last_back_trace_gc_no
= 1; /* Skip first one. */
1071 if (GC_gc_no
> last_back_trace_gc_no
) {
1074 # ifdef KEEP_BACK_PTRS
1076 /* Stops when GC_gc_no wraps; that's OK. */
1077 last_back_trace_gc_no
= (word
)(-1); /* disable others. */
1078 for (i
= 0; i
< GC_backtraces
; ++i
) {
1079 /* FIXME: This tolerates concurrent heap mutation, */
1080 /* which may cause occasional mysterious results. */
1081 /* We need to release the GC lock, since GC_print_callers */
1082 /* acquires it. It probably shouldn't. */
1084 GC_generate_random_backtrace_no_gc();
1087 last_back_trace_gc_no
= GC_gc_no
;
1090 # ifdef MAKE_BACK_GRAPH
1091 if (GC_print_back_height
)
1092 GC_print_back_graph_stats();
1096 if (GC_finalize_now
== 0) return;
1097 if (!GC_finalize_on_demand
) {
1098 (void) GC_invoke_finalizers();
1100 GC_ASSERT(GC_finalize_now
== 0);
1101 # endif /* Otherwise GC can run concurrently and add more */
1104 if (GC_finalizer_notifier
!= (void (*) GC_PROTO((void)))0
1105 && last_finalizer_notification
!= GC_gc_no
) {
1106 last_finalizer_notification
= GC_gc_no
;
1107 GC_finalizer_notifier();
1112 GC_PTR
GC_call_with_alloc_lock(GC_fn_type fn
,
1115 GC_PTR
GC_call_with_alloc_lock(fn
, client_data
)
1128 result
= (*fn
)(client_data
);
1130 # ifndef GC_ASSERTIONS
1131 UNSET_LOCK_HOLDER();
1132 # endif /* o.w. UNLOCK() does it implicitly */
1139 #if !defined(NO_DEBUGGING)
1141 void GC_print_finalization_stats()
1143 struct finalizable_object
*fo
= GC_finalize_now
;
1146 GC_printf3("%lu finalization table entries; %lu/%lu short/long disappearing links alive\n",
1147 GC_fo_entries
, (unsigned long)GC_dl_hashtbl
.entries
, (unsigned long)GC_ll_hashtbl
.entries
);
1148 for (; 0 != fo
; fo
= fo_next(fo
)) ++ready
;
1149 GC_printf1("%lu objects are eligible for immediate finalization\n", ready
);
1152 #endif /* NO_DEBUGGING */