aboutsummaryrefslogtreecommitdiff
path: root/boehm-gc/reclaim.c
blob: 407b4c68194dc0b287f81a55e5ea88e0ae8b2162 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
/* 
 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
 * Copyright (c) 1991-1994 by Xerox Corporation.  All rights reserved.
 *
 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
 * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
 *
 * Permission is hereby granted to use or copy this program
 * for any purpose,  provided the above notices are retained on all copies.
 * Permission to modify the code and to distribute modified code is granted,
 * provided the above notices are retained, and a notice that the code was
 * modified is included with the above copyright notice.
 */
/* Boehm, February 15, 1996 2:41 pm PST */

#include <stdio.h>
#include "gc_priv.h"

signed_word GC_mem_found = 0;
			/* Number of words of memory reclaimed     */

# ifdef FIND_LEAK
static void report_leak(p, sz)
ptr_t p;
word sz;
{
    if (HDR(p) -> hb_obj_kind == PTRFREE) {
        GC_err_printf0("Leaked atomic object at ");
    } else {
        GC_err_printf0("Leaked composite object at ");
    }
    if (GC_debugging_started && GC_has_debug_info(p)) {
        GC_print_obj(p);
    } else {
        GC_err_printf2("0x%lx (appr. size = %ld)\n",
       		      (unsigned long)p,
       		      (unsigned long)WORDS_TO_BYTES(sz));
    }
}

#   define FOUND_FREE(hblk, word_no) \
      if (abort_if_found) { \
         report_leak((ptr_t)hblk + WORDS_TO_BYTES(word_no), \
         	     HDR(hblk) -> hb_sz); \
      }
# else
#   define FOUND_FREE(hblk, word_no)
# endif

/*
 * reclaim phase
 *
 */


/*
 * Test whether a block is completely empty, i.e. contains no marked
 * objects.  This does not require the block to be in physical
 * memory.
 */
 
GC_bool GC_block_empty(hhdr)
register hdr * hhdr;
{
    register word *p = (word *)(&(hhdr -> hb_marks[0]));
    register word * plim =
	    		(word *)(&(hhdr -> hb_marks[MARK_BITS_SZ]));
    while (p < plim) {
	if (*p++) return(FALSE);
    }
    return(TRUE);
}

# ifdef GATHERSTATS
#   define INCR_WORDS(sz) n_words_found += (sz)
# else
#   define INCR_WORDS(sz)
# endif
/*
 * Restore unmarked small objects in h of size sz to the object
 * free list.  Returns the new list.
 * Clears unmarked objects.
 */
/*ARGSUSED*/
ptr_t GC_reclaim_clear(hbp, hhdr, sz, list, abort_if_found)
register struct hblk *hbp;	/* ptr to current heap block		*/
register hdr * hhdr;
GC_bool abort_if_found;		/* Abort if a reclaimable object is found */
register ptr_t list;
register word sz;
{
    register int word_no;
    register word *p, *q, *plim;
#   ifdef GATHERSTATS
        register int n_words_found = 0;
#   endif        
    
    p = (word *)(hbp->hb_body);
    word_no = HDR_WORDS;
    plim = (word *)((((word)hbp) + HBLKSIZE)
		   - WORDS_TO_BYTES(sz));

    /* go through all words in block */
	while( p <= plim )  {
	    if( mark_bit_from_hdr(hhdr, word_no) ) {
		p += sz;
	    } else {
		FOUND_FREE(hbp, word_no);
		INCR_WORDS(sz);
		/* object is available - put on list */
		    obj_link(p) = list;
		    list = ((ptr_t)p);
		/* Clear object, advance p to next object in the process */
		    q = p + sz;
                    p++; /* Skip link field */
                    while (p < q) {
			*p++ = 0;
		    }
	    }
	    word_no += sz;
	}
#   ifdef GATHERSTATS
	GC_mem_found += n_words_found;
#   endif
    return(list);
}

#ifndef SMALL_CONFIG

/*
 * A special case for 2 word composite objects (e.g. cons cells):
 */
/*ARGSUSED*/
ptr_t GC_reclaim_clear2(hbp, hhdr, list, abort_if_found)
register struct hblk *hbp;	/* ptr to current heap block		*/
hdr * hhdr;
GC_bool abort_if_found;		/* Abort if a reclaimable object is found */
register ptr_t list;
{
    register word * mark_word_addr = &(hhdr->hb_marks[divWORDSZ(HDR_WORDS)]);
    register word *p, *plim;
#   ifdef GATHERSTATS
        register int n_words_found = 0;
#   endif
    register word mark_word;
    register int i;
#   define DO_OBJ(start_displ) \
	if (!(mark_word & ((word)1 << start_displ))) { \
	    FOUND_FREE(hbp, p - (word *)hbp + start_displ); \
	    p[start_displ] = (word)list; \
	    list = (ptr_t)(p+start_displ); \
	    p[start_displ+1] = 0; \
	    INCR_WORDS(2); \
	}
    
    p = (word *)(hbp->hb_body);
    plim = (word *)(((word)hbp) + HBLKSIZE);

    /* go through all words in block */
	while( p < plim )  {
	    mark_word = *mark_word_addr++;
	    for (i = 0; i < WORDSZ; i += 8) {
		DO_OBJ(0);
		DO_OBJ(2);
		DO_OBJ(4);
		DO_OBJ(6);
		p += 8;
		mark_word >>= 8;
	    }
	}	        
#   ifdef GATHERSTATS
	GC_mem_found += n_words_found;
#   endif
    return(list);
#   undef DO_OBJ
}

/*
 * Another special case for 4 word composite objects:
 */
/*ARGSUSED*/
ptr_t GC_reclaim_clear4(hbp, hhdr, list, abort_if_found)
register struct hblk *hbp;	/* ptr to current heap block		*/
hdr * hhdr;
GC_bool abort_if_found;		/* Abort if a reclaimable object is found */
register ptr_t list;
{
    register word * mark_word_addr = &(hhdr->hb_marks[divWORDSZ(HDR_WORDS)]);
    register word *p, *plim;
#   ifdef GATHERSTATS
        register int n_words_found = 0;
#   endif
    register word mark_word;
#   define DO_OBJ(start_displ) \
	if (!(mark_word & ((word)1 << start_displ))) { \
	    FOUND_FREE(hbp, p - (word *)hbp + start_displ); \
	    p[start_displ] = (word)list; \
	    list = (ptr_t)(p+start_displ); \
	    p[start_displ+1] = 0; \
	    p[start_displ+2] = 0; \
	    p[start_displ+3] = 0; \
	    INCR_WORDS(4); \
	}
    
    p = (word *)(hbp->hb_body);
    plim = (word *)(((word)hbp) + HBLKSIZE);

    /* go through all words in block */
	while( p < plim )  {
	    mark_word = *mark_word_addr++;
	    DO_OBJ(0);
	    DO_OBJ(4);
	    DO_OBJ(8);
	    DO_OBJ(12);
	    DO_OBJ(16);
	    DO_OBJ(20);
	    DO_OBJ(24);
	    DO_OBJ(28);
#	    if CPP_WORDSZ == 64
	      DO_OBJ(32);
	      DO_OBJ(36);
	      DO_OBJ(40);
	      DO_OBJ(44);
	      DO_OBJ(48);
	      DO_OBJ(52);
	      DO_OBJ(56);
	      DO_OBJ(60);
#	    endif
	    p += WORDSZ;
	}	        
#   ifdef GATHERSTATS
	GC_mem_found += n_words_found;
#   endif
    return(list);
#   undef DO_OBJ
}

#endif /* !SMALL_CONFIG */

/* The same thing, but don't clear objects: */
/*ARGSUSED*/
ptr_t GC_reclaim_uninit(hbp, hhdr, sz, list, abort_if_found)
register struct hblk *hbp;	/* ptr to current heap block		*/
register hdr * hhdr;
GC_bool abort_if_found;		/* Abort if a reclaimable object is found */
register ptr_t list;
register word sz;
{
    register int word_no;
    register word *p, *plim;
#   ifdef GATHERSTATS
        register int n_words_found = 0;
#   endif
    
    p = (word *)(hbp->hb_body);
    word_no = HDR_WORDS;
    plim = (word *)((((word)hbp) + HBLKSIZE)
		   - WORDS_TO_BYTES(sz));

    /* go through all words in block */
	while( p <= plim )  {
	    if( !mark_bit_from_hdr(hhdr, word_no) ) {
		FOUND_FREE(hbp, word_no);
		INCR_WORDS(sz);
		/* object is available - put on list */
		    obj_link(p) = list;
		    list = ((ptr_t)p);
	    }
	    p += sz;
	    word_no += sz;
	}
#   ifdef GATHERSTATS
	GC_mem_found += n_words_found;
#   endif
    return(list);
}

#ifndef SMALL_CONFIG
/*
 * Another special case for 2 word atomic objects:
 */
/*ARGSUSED*/
ptr_t GC_reclaim_uninit2(hbp, hhdr, list, abort_if_found)
register struct hblk *hbp;	/* ptr to current heap block		*/
hdr * hhdr;
GC_bool abort_if_found;		/* Abort if a reclaimable object is found */
register ptr_t list;
{
    register word * mark_word_addr = &(hhdr->hb_marks[divWORDSZ(HDR_WORDS)]);
    register word *p, *plim;
#   ifdef GATHERSTATS
        register int n_words_found = 0;
#   endif
    register word mark_word;
    register int i;
#   define DO_OBJ(start_displ) \
	if (!(mark_word & ((word)1 << start_displ))) { \
	    FOUND_FREE(hbp, p - (word *)hbp + start_displ); \
	    p[start_displ] = (word)list; \
	    list = (ptr_t)(p+start_displ); \
	    INCR_WORDS(2); \
	}
    
    p = (word *)(hbp->hb_body);
    plim = (word *)(((word)hbp) + HBLKSIZE);

    /* go through all words in block */
	while( p < plim )  {
	    mark_word = *mark_word_addr++;
	    for (i = 0; i < WORDSZ; i += 8) {
		DO_OBJ(0);
		DO_OBJ(2);
		DO_OBJ(4);
		DO_OBJ(6);
		p += 8;
		mark_word >>= 8;
	    }
	}	        
#   ifdef GATHERSTATS
	GC_mem_found += n_words_found;
#   endif
    return(list);
#   undef DO_OBJ
}

/*
 * Another special case for 4 word atomic objects:
 */
/*ARGSUSED*/
ptr_t GC_reclaim_uninit4(hbp, hhdr, list, abort_if_found)
register struct hblk *hbp;	/* ptr to current heap block		*/
hdr * hhdr;
GC_bool abort_if_found;		/* Abort if a reclaimable object is found */
register ptr_t list;
{
    register word * mark_word_addr = &(hhdr->hb_marks[divWORDSZ(HDR_WORDS)]);
    register word *p, *plim;
#   ifdef GATHERSTATS
        register int n_words_found = 0;
#   endif
    register word mark_word;
#   define DO_OBJ(start_displ) \
	if (!(mark_word & ((word)1 << start_displ))) { \
	    FOUND_FREE(hbp, p - (word *)hbp + start_displ); \
	    p[start_displ] = (word)list; \
	    list = (ptr_t)(p+start_displ); \
	    INCR_WORDS(4); \
	}
    
    p = (word *)(hbp->hb_body);
    plim = (word *)(((word)hbp) + HBLKSIZE);

    /* go through all words in block */
	while( p < plim )  {
	    mark_word = *mark_word_addr++;
	    DO_OBJ(0);
	    DO_OBJ(4);
	    DO_OBJ(8);
	    DO_OBJ(12);
	    DO_OBJ(16);
	    DO_OBJ(20);
	    DO_OBJ(24);
	    DO_OBJ(28);
#	    if CPP_WORDSZ == 64
	      DO_OBJ(32);
	      DO_OBJ(36);
	      DO_OBJ(40);
	      DO_OBJ(44);
	      DO_OBJ(48);
	      DO_OBJ(52);
	      DO_OBJ(56);
	      DO_OBJ(60);
#	    endif
	    p += WORDSZ;
	}	        
#   ifdef GATHERSTATS
	GC_mem_found += n_words_found;
#   endif
    return(list);
#   undef DO_OBJ
}

/* Finally the one word case, which never requires any clearing: */
/*ARGSUSED*/
ptr_t GC_reclaim1(hbp, hhdr, list, abort_if_found)
register struct hblk *hbp;	/* ptr to current heap block		*/
hdr * hhdr;
GC_bool abort_if_found;		/* Abort if a reclaimable object is found */
register ptr_t list;
{
    register word * mark_word_addr = &(hhdr->hb_marks[divWORDSZ(HDR_WORDS)]);
    register word *p, *plim;
#   ifdef GATHERSTATS
        register int n_words_found = 0;
#   endif
    register word mark_word;
    register int i;
#   define DO_OBJ(start_displ) \
	if (!(mark_word & ((word)1 << start_displ))) { \
	    FOUND_FREE(hbp, p - (word *)hbp + start_displ); \
	    p[start_displ] = (word)list; \
	    list = (ptr_t)(p+start_displ); \
	    INCR_WORDS(1); \
	}
    
    p = (word *)(hbp->hb_body);
    plim = (word *)(((word)hbp) + HBLKSIZE);

    /* go through all words in block */
	while( p < plim )  {
	    mark_word = *mark_word_addr++;
	    for (i = 0; i < WORDSZ; i += 4) {
		DO_OBJ(0);
		DO_OBJ(1);
		DO_OBJ(2);
		DO_OBJ(3);
		p += 4;
		mark_word >>= 4;
	    }
	}	        
#   ifdef GATHERSTATS
	GC_mem_found += n_words_found;
#   endif
    return(list);
#   undef DO_OBJ
}

#endif /* !SMALL_CONFIG */

/*
 * Restore unmarked small objects in the block pointed to by hbp
 * to the appropriate object free list.
 * If entirely empty blocks are to be completely deallocated, then
 * caller should perform that check.
 */
void GC_reclaim_small_nonempty_block(hbp, abort_if_found)
register struct hblk *hbp;	/* ptr to current heap block		*/
int abort_if_found;		/* Abort if a reclaimable object is found */
{
    hdr * hhdr;
    register word sz;		/* size of objects in current block	*/
    register struct obj_kind * ok;
    register ptr_t * flh;
    register int kind;
    
    hhdr = HDR(hbp);
    sz = hhdr -> hb_sz;
    hhdr -> hb_last_reclaimed = (unsigned short) GC_gc_no;
    kind = hhdr -> hb_obj_kind;
    ok = &GC_obj_kinds[kind];
    flh = &(ok -> ok_freelist[sz]);
    GC_write_hint(hbp);

    if (ok -> ok_init) {
      switch(sz) {
#      ifndef SMALL_CONFIG
        case 1:
            *flh = GC_reclaim1(hbp, hhdr, *flh, abort_if_found);
            break;
        case 2:
            *flh = GC_reclaim_clear2(hbp, hhdr, *flh, abort_if_found);
            break;
        case 4:
            *flh = GC_reclaim_clear4(hbp, hhdr, *flh, abort_if_found);
            break;
#      endif
        default:
            *flh = GC_reclaim_clear(hbp, hhdr, sz, *flh, abort_if_found);
            break;
      }
    } else {
      switch(sz) {
#      ifndef SMALL_CONFIG
        case 1:
            *flh = GC_reclaim1(hbp, hhdr, *flh, abort_if_found);
            break;
        case 2:
            *flh = GC_reclaim_uninit2(hbp, hhdr, *flh, abort_if_found);
            break;
        case 4:
            *flh = GC_reclaim_uninit4(hbp, hhdr, *flh, abort_if_found);
            break;
#      endif
        default:
            *flh = GC_reclaim_uninit(hbp, hhdr, sz, *flh, abort_if_found);
            break;
      }
    } 
    if (IS_UNCOLLECTABLE(kind)) GC_set_hdr_marks(hhdr);
}

/*
 * Restore an unmarked large object or an entirely empty blocks of small objects
 * to the heap block free list.
 * Otherwise enqueue the block for later processing
 * by GC_reclaim_small_nonempty_block.
 * If abort_if_found is TRUE, then process any block immediately.
 */
void GC_reclaim_block(hbp, abort_if_found)
register struct hblk *hbp;	/* ptr to current heap block		*/
word abort_if_found;		/* Abort if a reclaimable object is found */
{
    register hdr * hhdr;
    register word sz;		/* size of objects in current block	*/
    register struct obj_kind * ok;
    struct hblk ** rlh;

    hhdr = HDR(hbp);
    sz = hhdr -> hb_sz;
    ok = &GC_obj_kinds[hhdr -> hb_obj_kind];

    if( sz > MAXOBJSZ ) {  /* 1 big object */
        if( !mark_bit_from_hdr(hhdr, HDR_WORDS) ) {
	    FOUND_FREE(hbp, HDR_WORDS);
#	    ifdef GATHERSTATS
	        GC_mem_found += sz;
#	    endif
	    GC_freehblk(hbp);
	}
    } else {
        GC_bool empty = GC_block_empty(hhdr);
        if (abort_if_found) {
    	  GC_reclaim_small_nonempty_block(hbp, (int)abort_if_found);
        } else if (empty) {
#	  ifdef GATHERSTATS
            GC_mem_found += BYTES_TO_WORDS(HBLKSIZE);
#	  endif
          GC_freehblk(hbp);
        } else {
          /* group of smaller objects, enqueue the real work */
          rlh = &(ok -> ok_reclaim_list[sz]);
          hhdr -> hb_next = *rlh;
          *rlh = hbp;
        }
    }
}

#if !defined(NO_DEBUGGING)
/* Routines to gather and print heap block info 	*/
/* intended for debugging.  Otherwise should be called	*/
/* with lock.						*/
static size_t number_of_blocks;
static size_t total_bytes;

/* Number of set bits in a word.  Not performance critical.	*/
static int set_bits(n)
word n;
{
    register word m = n;
    register int result = 0;
    
    while (m > 0) {
    	if (m & 1) result++;
    	m >>= 1;
    }
    return(result);
}

/* Return the number of set mark bits in the given header	*/
int GC_n_set_marks(hhdr)
hdr * hhdr;
{
    register int result = 0;
    register int i;
    
    for (i = 0; i < MARK_BITS_SZ; i++) {
        result += set_bits(hhdr -> hb_marks[i]);
    }
    return(result);
}

/*ARGSUSED*/
void GC_print_block_descr(h, dummy)
struct hblk *h;
word dummy;
{
    register hdr * hhdr = HDR(h);
    register size_t bytes = WORDS_TO_BYTES(hhdr -> hb_sz);
    
    GC_printf3("(%lu:%lu,%lu)", (unsigned long)(hhdr -> hb_obj_kind),
    			        (unsigned long)bytes,
    			        (unsigned long)(GC_n_set_marks(hhdr)));
    bytes += HDR_BYTES + HBLKSIZE-1;
    bytes &= ~(HBLKSIZE-1);
    total_bytes += bytes;
    number_of_blocks++;
}

void GC_print_block_list()
{
    GC_printf0("(kind(0=ptrfree,1=normal,2=unc.,3=stubborn):size_in_bytes, #_marks_set)\n");
    number_of_blocks = 0;
    total_bytes = 0;
    GC_apply_to_all_blocks(GC_print_block_descr, (word)0);
    GC_printf2("\nblocks = %lu, bytes = %lu\n",
    	       (unsigned long)number_of_blocks,
    	       (unsigned long)total_bytes);
}

#endif /* NO_DEBUGGING */

/*
 * Do the same thing on the entire heap, after first clearing small object
 * free lists (if we are not just looking for leaks).
 */
void GC_start_reclaim(abort_if_found)
int abort_if_found;		/* Abort if a GC_reclaimable object is found */
{
    int kind;
    
    /* Clear reclaim- and free-lists */
      for (kind = 0; kind < GC_n_kinds; kind++) {
        register ptr_t *fop;
        register ptr_t *lim;
        register struct hblk ** rlp;
        register struct hblk ** rlim;
        register struct hblk ** rlist = GC_obj_kinds[kind].ok_reclaim_list;
        
        if (rlist == 0) continue;	/* This kind not used.	*/
        if (!abort_if_found) {
            lim = &(GC_obj_kinds[kind].ok_freelist[MAXOBJSZ+1]);
	    for( fop = GC_obj_kinds[kind].ok_freelist; fop < lim; fop++ ) {
	      *fop = 0;
	    }
	} /* otherwise free list objects are marked, 	*/
	  /* and its safe to leave them			*/
	rlim = rlist + MAXOBJSZ+1;
	for( rlp = rlist; rlp < rlim; rlp++ ) {
	    *rlp = 0;
	}
      }
    
#   ifdef PRINTBLOCKS
        GC_printf0("GC_reclaim: current block sizes:\n");
        GC_print_block_list();
#   endif

  /* Go through all heap blocks (in hblklist) and reclaim unmarked objects */
  /* or enqueue the block for later processing.				   */
    GC_apply_to_all_blocks(GC_reclaim_block, (word)abort_if_found);
    
}

/*
 * Sweep blocks of the indicated object size and kind until either the
 * appropriate free list is nonempty, or there are no more blocks to
 * sweep.
 */
void GC_continue_reclaim(sz, kind)
word sz;	/* words */
int kind;
{
    register hdr * hhdr;
    register struct hblk * hbp;
    register struct obj_kind * ok = &(GC_obj_kinds[kind]);
    struct hblk ** rlh = ok -> ok_reclaim_list;
    ptr_t *flh = &(ok -> ok_freelist[sz]);
    
    if (rlh == 0) return;	/* No blocks of this kind.	*/
    rlh += sz;
    while ((hbp = *rlh) != 0) {
        hhdr = HDR(hbp);
        *rlh = hhdr -> hb_next;
        GC_reclaim_small_nonempty_block(hbp, FALSE);
        if (*flh != 0) break;
    }
}

/*
 * Reclaim all small blocks waiting to be reclaimed.
 * Abort and return FALSE when/if (*stop_func)() returns TRUE.
 * If this returns TRUE, then it's safe to restart the world
 * with incorrectly cleared mark bits.
 * If ignore_old is TRUE, then reclain only blocks that have been 
 * recently reclaimed, and discard the rest.
 * Stop_func may be 0.
 */
GC_bool GC_reclaim_all(stop_func, ignore_old)
GC_stop_func stop_func;
GC_bool ignore_old;
{
    register word sz;
    register int kind;
    register hdr * hhdr;
    register struct hblk * hbp;
    register struct obj_kind * ok;
    struct hblk ** rlp;
    struct hblk ** rlh;
#   ifdef PRINTTIMES
	CLOCK_TYPE start_time;
	CLOCK_TYPE done_time;
	
	GET_TIME(start_time);
#   endif
    
    for (kind = 0; kind < GC_n_kinds; kind++) {
    	ok = &(GC_obj_kinds[kind]);
    	rlp = ok -> ok_reclaim_list;
    	if (rlp == 0) continue;
    	for (sz = 1; sz <= MAXOBJSZ; sz++) {
    	    rlh = rlp + sz;
    	    while ((hbp = *rlh) != 0) {
    	        if (stop_func != (GC_stop_func)0 && (*stop_func)()) {
    	            return(FALSE);
    	        }
        	hhdr = HDR(hbp);
        	*rlh = hhdr -> hb_next;
        	if (!ignore_old || hhdr -> hb_last_reclaimed == GC_gc_no - 1) {
        	    /* It's likely we'll need it this time, too	*/
        	    /* It's been touched recently, so this	*/
        	    /* shouldn't trigger paging.		*/
        	    GC_reclaim_small_nonempty_block(hbp, FALSE);
        	}
            }
        }
    }
#   ifdef PRINTTIMES
	GET_TIME(done_time);
	GC_printf1("Disposing of reclaim lists took %lu msecs\n",
	           MS_TIME_DIFF(done_time,start_time));
#   endif
    return(TRUE);
}