boost_1_45_0/tools/build/v2/engine/src/boehm_gc/reclaim.c - nest-learning-thermostat/5.0/boost - Git at Google

 /*
  * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
  * Copyright (c) 1991-1996 by Xerox Corporation.  All rights reserved.
  * Copyright (c) 1996-1999 by Silicon Graphics.  All rights reserved.
  * Copyright (c) 1999-2004 Hewlett-Packard Development Company, L.P.
  *
  * 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.
  */

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

 signed_word GC_bytes_found = 0;
 			/* Number of bytes of memory reclaimed     */

 #if defined(PARALLEL_MARK) || defined(THREAD_LOCAL_ALLOC)
   word GC_fl_builder_count = 0;
 	/* Number of threads currently building free lists without 	*/
 	/* holding GC lock.  It is not safe to collect if this is 	*/
 	/* nonzero.							*/
 #endif /* PARALLEL_MARK */

 /* We defer printing of leaked objects until we're done with the GC	*/
 /* cycle, since the routine for printing objects needs to run outside	*/
 /* the collector, e.g. without the allocation lock.			*/
 #define MAX_LEAKED 40
 ptr_t GC_leaked[MAX_LEAKED];
 unsigned GC_n_leaked = 0;

 GC_bool GC_have_errors = FALSE;

 void GC_add_leaked(ptr_t leaked)
 {
     if (GC_n_leaked < MAX_LEAKED) {
       GC_have_errors = TRUE;
       GC_leaked[GC_n_leaked++] = leaked;
       /* Make sure it's not reclaimed this cycle */
         GC_set_mark_bit(leaked);
     }
 }

 static GC_bool printing_errors = FALSE;
 /* Print all objects on the list after printing any smashed objs. 	*/
 /* Clear both lists.							*/
 void GC_print_all_errors ()
 {
     unsigned i;

     LOCK();
     if (printing_errors) {
 	UNLOCK();
 	return;
     }
     printing_errors = TRUE;
     UNLOCK();
     if (GC_debugging_started) GC_print_all_smashed();
     for (i = 0; i < GC_n_leaked; ++i) {
 	ptr_t p = GC_leaked[i];
 	if (HDR(p) -> hb_obj_kind == PTRFREE) {
 	    GC_err_printf("Leaked atomic object at ");
 	} else {
 	    GC_err_printf("Leaked composite object at ");
 	}
 	GC_print_heap_obj(p);
 	GC_err_printf("\n");
 	GC_free(p);
 	GC_leaked[i] = 0;
     }
     GC_n_leaked = 0;
     printing_errors = FALSE;
 }


 /*
  * 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(hdr *hhdr)
 {
     return (hhdr -> hb_n_marks == 0);
 }

 GC_bool GC_block_nearly_full(hdr *hhdr)
 {
     return (hhdr -> hb_n_marks > 7 * HBLK_OBJS(hhdr -> hb_sz)/8);
 }

 /* FIXME: This should perhaps again be specialized for USE_MARK_BYTES	*/
 /* and USE_MARK_BITS cases.						*/

 /*
  * Restore unmarked small objects in h of size sz to the object
  * free list.  Returns the new list.
  * Clears unmarked objects.  Sz is in bytes.
  */
 /*ARGSUSED*/
 ptr_t GC_reclaim_clear(struct hblk *hbp, hdr *hhdr, size_t sz,
 		       ptr_t list, signed_word *count)
 {
     word bit_no = 0;
     word *p, *q, *plim;
     signed_word n_bytes_found = 0;

     GC_ASSERT(hhdr == GC_find_header((ptr_t)hbp));
     GC_ASSERT(sz == hhdr -> hb_sz);
     GC_ASSERT((sz & (BYTES_PER_WORD-1)) == 0);
     p = (word *)(hbp->hb_body);
     plim = (word *)(hbp->hb_body + HBLKSIZE - sz);

     /* go through all words in block */
 	while( p <= plim )  {
 	    if( mark_bit_from_hdr(hhdr, bit_no) ) {
 	        p = (word *)((ptr_t)p + sz);
 	    } else {
 		n_bytes_found += 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 = (word *)((ptr_t)p + sz);
 #		    ifdef USE_MARK_BYTES
 		      GC_ASSERT(!(sz & 1)
 				&& !((word)p & (2 * sizeof(word) - 1)));
 		      p[1] = 0;
                       p += 2;
                       while (p < q) {
 			CLEAR_DOUBLE(p);
 			p += 2;
 		      }
 #		    else
                       p++; /* Skip link field */
                       while (p < q) {
 			*p++ = 0;
 		      }
 #		    endif
 	    }
 	    bit_no += MARK_BIT_OFFSET(sz);
 	}
     *count += n_bytes_found;
     return(list);
 }

 /* The same thing, but don't clear objects: */
 /*ARGSUSED*/
 ptr_t GC_reclaim_uninit(struct hblk *hbp, hdr *hhdr, size_t sz,
 			ptr_t list, signed_word *count)
 {
     word bit_no = 0;
     word *p, *plim;
     signed_word n_bytes_found = 0;

     GC_ASSERT(sz == hhdr -> hb_sz);
     p = (word *)(hbp->hb_body);
     plim = (word *)((ptr_t)hbp + HBLKSIZE - sz);

     /* go through all words in block */
 	while( p <= plim )  {
 	    if( !mark_bit_from_hdr(hhdr, bit_no) ) {
 		n_bytes_found += sz;
 		/* object is available - put on list */
 		    obj_link(p) = list;
 		    list = ((ptr_t)p);
 	    }
 	    p = (word *)((ptr_t)p + sz);
 	    bit_no += MARK_BIT_OFFSET(sz);
 	}
     *count += n_bytes_found;
     return(list);
 }

 /* Don't really reclaim objects, just check for unmarked ones: */
 /*ARGSUSED*/
 void GC_reclaim_check(struct hblk *hbp, hdr *hhdr, word sz)
 {
     word bit_no = 0;
     ptr_t p, plim;

     GC_ASSERT(sz == hhdr -> hb_sz);
     p = hbp->hb_body;
     plim = p + HBLKSIZE - sz;

     /* go through all words in block */
 	while( p <= plim )  {
 	    if( !mark_bit_from_hdr(hhdr, bit_no) ) {
 		GC_add_leaked(p);
 	    }
 	    p += sz;
 	    bit_no += MARK_BIT_OFFSET(sz);
 	}
 }


 /*
  * Generic procedure to rebuild a free list in hbp.
  * Also called directly from GC_malloc_many.
  * Sz is now in bytes.
  */
 ptr_t GC_reclaim_generic(struct hblk * hbp, hdr *hhdr, size_t sz,
 			 GC_bool init, ptr_t list, signed_word *count)
 {
     ptr_t result = list;

     GC_ASSERT(GC_find_header((ptr_t)hbp) == hhdr);
     GC_remove_protection(hbp, 1, (hhdr)->hb_descr == 0 /* Pointer-free? */);
     if (init) {
       result = GC_reclaim_clear(hbp, hhdr, sz, list, count);
     } else {
       GC_ASSERT((hhdr)->hb_descr == 0 /* Pointer-free block */);
       result = GC_reclaim_uninit(hbp, hhdr, sz, list, count);
     }
     if (IS_UNCOLLECTABLE(hhdr -> hb_obj_kind)) GC_set_hdr_marks(hhdr);
     return result;
 }

 /*
  * 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(struct hblk *hbp,
 				     int report_if_found, signed_word *count)
 {
     hdr *hhdr = HDR(hbp);
     size_t sz = hhdr -> hb_sz;
     int kind = hhdr -> hb_obj_kind;
     struct obj_kind * ok = &GC_obj_kinds[kind];
     void **flh = &(ok -> ok_freelist[BYTES_TO_GRANULES(sz)]);

     hhdr -> hb_last_reclaimed = (unsigned short) GC_gc_no;

     if (report_if_found) {
 	GC_reclaim_check(hbp, hhdr, sz);
     } else {
         *flh = GC_reclaim_generic(hbp, hhdr, sz,
 				  (ok -> ok_init || GC_debugging_started),
 	 			  *flh, &GC_bytes_found);
     }
 }

 /*
  * 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 report_if_found is TRUE, then process any block immediately, and
  * simply report free objects; do not actually reclaim them.
  */
 void GC_reclaim_block(struct hblk *hbp, word report_if_found)
 {
     hdr * hhdr = HDR(hbp);
     size_t sz = hhdr -> hb_sz;	/* size of objects in current block	*/
     struct obj_kind * ok = &GC_obj_kinds[hhdr -> hb_obj_kind];
     struct hblk ** rlh;

     if( sz > MAXOBJBYTES ) {  /* 1 big object */
         if( !mark_bit_from_hdr(hhdr, 0) ) {
 	    if (report_if_found) {
 	      GC_add_leaked((ptr_t)hbp);
 	    } else {
 	      size_t blocks = OBJ_SZ_TO_BLOCKS(sz);
 	      if (blocks > 1) {
 	        GC_large_allocd_bytes -= blocks * HBLKSIZE;
 	      }
 	      GC_bytes_found += sz;
 	      GC_freehblk(hbp);
 	    }
 	} else {
 	    if (hhdr -> hb_descr != 0) {
 	      GC_composite_in_use += sz;
 	    } else {
 	      GC_atomic_in_use += sz;
 	    }
 	}
     } else {
         GC_bool empty = GC_block_empty(hhdr);
 #	ifdef PARALLEL_MARK
 	  /* Count can be low or one too high because we sometimes	*/
 	  /* have to ignore decrements.  Objects can also potentially   */
 	  /* be repeatedly marked by each marker.			*/
 	  /* Here we assume two markers, but this is extremely		*/
 	  /* unlikely to fail spuriously with more.  And if it does, it	*/
 	  /* should be looked at.					*/
 	  GC_ASSERT(hhdr -> hb_n_marks <= 2 * (HBLKSIZE/sz + 1) + 16);
 #	else
 	  GC_ASSERT(sz * hhdr -> hb_n_marks <= HBLKSIZE);
 #	endif
 	if (hhdr -> hb_descr != 0) {
 	  GC_composite_in_use += sz * hhdr -> hb_n_marks;
 	} else {
 	  GC_atomic_in_use += sz * hhdr -> hb_n_marks;
 	}
         if (report_if_found) {
     	  GC_reclaim_small_nonempty_block(hbp, (int)report_if_found,
 					  &GC_bytes_found);
         } else if (empty) {
           GC_bytes_found += HBLKSIZE;
           GC_freehblk(hbp);
         } else if (TRUE != GC_block_nearly_full(hhdr)){
           /* group of smaller objects, enqueue the real work */
           rlh = &(ok -> ok_reclaim_list[BYTES_TO_GRANULES(sz)]);
           hhdr -> hb_next = *rlh;
           *rlh = hbp;
         } /* else not worth salvaging. */
 	/* We used to do the nearly_full check later, but we 	*/
 	/* already have the right cache context here.  Also	*/
 	/* doing it here avoids some silly lock contention in	*/
 	/* GC_malloc_many.					*/
     }
 }

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

 struct Print_stats
 {
 	size_t number_of_blocks;
 	size_t total_bytes;
 };

 #ifdef USE_MARK_BYTES

 /* Return the number of set mark bits in the given header	*/
 int GC_n_set_marks(hdr *hhdr)
 {
     int result = 0;
     int i;
     size_t sz = hhdr -> hb_sz;
     int offset = MARK_BIT_OFFSET(sz);
     int limit = FINAL_MARK_BIT(sz);

     for (i = 0; i < limit; i += offset) {
         result += hhdr -> hb_marks[i];
     }
     GC_ASSERT(hhdr -> hb_marks[limit]);
     return(result);
 }

 #else

 /* Number of set bits in a word.  Not performance critical.	*/
 static int set_bits(word n)
 {
     word m = n;
     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(hdr *hhdr)
 {
     int result = 0;
     int i;
     int n_mark_words;
 #   ifdef MARK_BIT_PER_OBJ
       int n_objs = HBLK_OBJS(hhdr -> hb_sz);

       if (0 == n_objs) n_objs = 1;
       n_mark_words = divWORDSZ(n_objs + WORDSZ - 1);
 #   else /* MARK_BIT_PER_GRANULE */
       n_mark_words = MARK_BITS_SZ;
 #   endif
     for (i = 0; i < n_mark_words - 1; i++) {
         result += set_bits(hhdr -> hb_marks[i]);
     }
 #   ifdef MARK_BIT_PER_OBJ
       result += set_bits((hhdr -> hb_marks[n_mark_words - 1])
 		         << (n_mark_words * WORDSZ - n_objs));
 #   else
       result += set_bits(hhdr -> hb_marks[n_mark_words - 1]);
 #   endif
     return(result - 1);
 }

 #endif /* !USE_MARK_BYTES  */

 /*ARGSUSED*/
 void GC_print_block_descr(struct hblk *h, word /* struct PrintStats */ raw_ps)
 {
     hdr * hhdr = HDR(h);
     size_t bytes = hhdr -> hb_sz;
     struct Print_stats *ps;
     unsigned n_marks = GC_n_set_marks(hhdr);

     if (hhdr -> hb_n_marks != n_marks) {
       GC_printf("(%u:%u,%u!=%u)", hhdr -> hb_obj_kind,
     			          bytes,
     			          hhdr -> hb_n_marks, n_marks);
     } else {
       GC_printf("(%u:%u,%u)", hhdr -> hb_obj_kind,
     			      bytes, n_marks);
     }
     bytes += HBLKSIZE-1;
     bytes &= ~(HBLKSIZE-1);

     ps = (struct Print_stats *)raw_ps;
     ps->total_bytes += bytes;
     ps->number_of_blocks++;
 }

 void GC_print_block_list()
 {
     struct Print_stats pstats;

     GC_printf("(kind(0=ptrfree,1=normal,2=unc.):size_in_bytes, #_marks_set)\n");
     pstats.number_of_blocks = 0;
     pstats.total_bytes = 0;
     GC_apply_to_all_blocks(GC_print_block_descr, (word)&pstats);
     GC_printf("\nblocks = %lu, bytes = %lu\n",
     	      (unsigned long)pstats.number_of_blocks,
     	      (unsigned long)pstats.total_bytes);
 }

 /* Currently for debugger use only: */
 void GC_print_free_list(int kind, size_t sz_in_granules)
 {
     struct obj_kind * ok = &GC_obj_kinds[kind];
     ptr_t flh = ok -> ok_freelist[sz_in_granules];
     struct hblk *lastBlock = 0;
     int n = 0;

     while (flh){
         struct hblk *block = HBLKPTR(flh);
         if (block != lastBlock){
             GC_printf("\nIn heap block at 0x%x:\n\t", block);
             lastBlock = block;
         }
         GC_printf("%d: 0x%x;", ++n, flh);
         flh = obj_link(flh);
     }
 }

 #endif /* NO_DEBUGGING */

 /*
  * Clear all obj_link pointers in the list of free objects *flp.
  * Clear *flp.
  * This must be done before dropping a list of free gcj-style objects,
  * since may otherwise end up with dangling "descriptor" pointers.
  * It may help for other pointer-containing objects.
  */
 void GC_clear_fl_links(void **flp)
 {
     void *next = *flp;

     while (0 != next) {
        *flp = 0;
        flp = &(obj_link(next));
        next = *flp;
     }
 }

 /*
  * Perform GC_reclaim_block on the entire heap, after first clearing
  * small object free lists (if we are not just looking for leaks).
  */
 void GC_start_reclaim(GC_bool report_if_found)
 {
     unsigned kind;

 #   if defined(PARALLEL_MARK) || defined(THREAD_LOCAL_ALLOC)
       GC_ASSERT(0 == GC_fl_builder_count);
 #   endif
     /* Reset in use counters.  GC_reclaim_block recomputes them. */
       GC_composite_in_use = 0;
       GC_atomic_in_use = 0;
     /* Clear reclaim- and free-lists */
       for (kind = 0; kind < GC_n_kinds; kind++) {
         void **fop;
         void **lim;
         struct hblk ** rlp;
         struct hblk ** rlim;
         struct hblk ** rlist = GC_obj_kinds[kind].ok_reclaim_list;
 	GC_bool should_clobber = (GC_obj_kinds[kind].ok_descriptor != 0);

         if (rlist == 0) continue;	/* This kind not used.	*/
         if (!report_if_found) {
             lim = &(GC_obj_kinds[kind].ok_freelist[MAXOBJGRANULES+1]);
 	    for( fop = GC_obj_kinds[kind].ok_freelist; fop < lim; fop++ ) {
 	      if (*fop != 0) {
 		if (should_clobber) {
 		  GC_clear_fl_links(fop);
 		} else {
 	          *fop = 0;
 		}
 	      }
 	    }
 	} /* otherwise free list objects are marked, 	*/
 	  /* and its safe to leave them			*/
 	rlim = rlist + MAXOBJGRANULES+1;
 	for( rlp = rlist; rlp < rlim; rlp++ ) {
 	    *rlp = 0;
 	}
       }


   /* 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)report_if_found);

 # ifdef EAGER_SWEEP
     /* This is a very stupid thing to do.  We make it possible anyway,	*/
     /* so that you can convince yourself that it really is very stupid.	*/
     GC_reclaim_all((GC_stop_func)0, FALSE);
 # endif
 # if defined(PARALLEL_MARK) || defined(THREAD_LOCAL_ALLOC)
     GC_ASSERT(0 == GC_fl_builder_count);
 # endif

 }

 /*
  * 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(size_t sz /* granules */, int kind)
 {
     hdr * hhdr;
     struct hblk * hbp;
     struct obj_kind * ok = &(GC_obj_kinds[kind]);
     struct hblk ** rlh = ok -> ok_reclaim_list;
     void **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, &GC_bytes_found);
         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 reclaim only blocks that have been
  * recently reclaimed, and discard the rest.
  * Stop_func may be 0.
  */
 GC_bool GC_reclaim_all(GC_stop_func stop_func, GC_bool ignore_old)
 {
     word sz;
     unsigned kind;
     hdr * hhdr;
     struct hblk * hbp;
     struct obj_kind * ok;
     struct hblk ** rlp;
     struct hblk ** rlh;
     CLOCK_TYPE start_time;
     CLOCK_TYPE done_time;

     if (GC_print_stats == VERBOSE)
 	GET_TIME(start_time);

     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 <= MAXOBJGRANULES; 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, &GC_bytes_found);
         	}
             }
         }
     }
     if (GC_print_stats == VERBOSE) {
 	GET_TIME(done_time);
 	GC_log_printf("Disposing of reclaim lists took %lu msecs\n",
 	          MS_TIME_DIFF(done_time,start_time));
     }
     return(TRUE);
 }
	/*
	* Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
	* Copyright (c) 1991-1996 by Xerox Corporation. All rights reserved.
	* Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
	* Copyright (c) 1999-2004 Hewlett-Packard Development Company, L.P.
	*
	* 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.
	*/

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

	signed_word GC_bytes_found = 0;
	/* Number of bytes of memory reclaimed */

	#if defined(PARALLEL_MARK) \|\| defined(THREAD_LOCAL_ALLOC)
	word GC_fl_builder_count = 0;
	/* Number of threads currently building free lists without */
	/* holding GC lock. It is not safe to collect if this is */
	/* nonzero. */
	#endif /* PARALLEL_MARK */

	/* We defer printing of leaked objects until we're done with the GC */
	/* cycle, since the routine for printing objects needs to run outside */
	/* the collector, e.g. without the allocation lock. */
	#define MAX_LEAKED 40
	ptr_t GC_leaked[MAX_LEAKED];
	unsigned GC_n_leaked = 0;

	GC_bool GC_have_errors = FALSE;

	void GC_add_leaked(ptr_t leaked)
	{
	if (GC_n_leaked < MAX_LEAKED) {
	GC_have_errors = TRUE;
	GC_leaked[GC_n_leaked++] = leaked;
	/* Make sure it's not reclaimed this cycle */
	GC_set_mark_bit(leaked);
	}
	}

	static GC_bool printing_errors = FALSE;
	/* Print all objects on the list after printing any smashed objs. */
	/* Clear both lists. */
	void GC_print_all_errors ()
	{
	unsigned i;

	LOCK();
	if (printing_errors) {
	UNLOCK();
	return;
	}
	printing_errors = TRUE;
	UNLOCK();
	if (GC_debugging_started) GC_print_all_smashed();
	for (i = 0; i < GC_n_leaked; ++i) {
	ptr_t p = GC_leaked[i];
	if (HDR(p) -> hb_obj_kind == PTRFREE) {
	GC_err_printf("Leaked atomic object at ");
	} else {
	GC_err_printf("Leaked composite object at ");
	}
	GC_print_heap_obj(p);
	GC_err_printf("\n");
	GC_free(p);
	GC_leaked[i] = 0;
	}
	GC_n_leaked = 0;
	printing_errors = FALSE;
	}


	/*
	* 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(hdr *hhdr)
	{
	return (hhdr -> hb_n_marks == 0);
	}

	GC_bool GC_block_nearly_full(hdr *hhdr)
	{
	return (hhdr -> hb_n_marks > 7 * HBLK_OBJS(hhdr -> hb_sz)/8);
	}

	/* FIXME: This should perhaps again be specialized for USE_MARK_BYTES */
	/* and USE_MARK_BITS cases. */

	/*
	* Restore unmarked small objects in h of size sz to the object
	* free list. Returns the new list.
	* Clears unmarked objects. Sz is in bytes.
	*/
	/ARGSUSED/
	ptr_t GC_reclaim_clear(struct hblk hbp, hdr hhdr, size_t sz,
	ptr_t list, signed_word *count)
	{
	word bit_no = 0;
	word p, q, *plim;
	signed_word n_bytes_found = 0;

	GC_ASSERT(hhdr == GC_find_header((ptr_t)hbp));
	GC_ASSERT(sz == hhdr -> hb_sz);
	GC_ASSERT((sz & (BYTES_PER_WORD-1)) == 0);
	p = (word *)(hbp->hb_body);
	plim = (word *)(hbp->hb_body + HBLKSIZE - sz);

	/* go through all words in block */
	while( p <= plim ) {
	if( mark_bit_from_hdr(hhdr, bit_no) ) {
	p = (word *)((ptr_t)p + sz);
	} else {
	n_bytes_found += 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 = (word *)((ptr_t)p + sz);
	# ifdef USE_MARK_BYTES
	GC_ASSERT(!(sz & 1)
	&& !((word)p & (2 * sizeof(word) - 1)));
	p[1] = 0;
	p += 2;
	while (p < q) {
	CLEAR_DOUBLE(p);
	p += 2;
	}
	# else
	p++; /* Skip link field */
	while (p < q) {
	*p++ = 0;
	}
	# endif
	}
	bit_no += MARK_BIT_OFFSET(sz);
	}
	*count += n_bytes_found;
	return(list);
	}

	/* The same thing, but don't clear objects: */
	/ARGSUSED/
	ptr_t GC_reclaim_uninit(struct hblk hbp, hdr hhdr, size_t sz,
	ptr_t list, signed_word *count)
	{
	word bit_no = 0;
	word p, plim;
	signed_word n_bytes_found = 0;

	GC_ASSERT(sz == hhdr -> hb_sz);
	p = (word *)(hbp->hb_body);
	plim = (word *)((ptr_t)hbp + HBLKSIZE - sz);

	/* go through all words in block */
	while( p <= plim ) {
	if( !mark_bit_from_hdr(hhdr, bit_no) ) {
	n_bytes_found += sz;
	/* object is available - put on list */
	obj_link(p) = list;
	list = ((ptr_t)p);
	}
	p = (word *)((ptr_t)p + sz);
	bit_no += MARK_BIT_OFFSET(sz);
	}
	*count += n_bytes_found;
	return(list);
	}

	/* Don't really reclaim objects, just check for unmarked ones: */
	/ARGSUSED/
	void GC_reclaim_check(struct hblk hbp, hdr hhdr, word sz)
	{
	word bit_no = 0;
	ptr_t p, plim;

	GC_ASSERT(sz == hhdr -> hb_sz);
	p = hbp->hb_body;
	plim = p + HBLKSIZE - sz;

	/* go through all words in block */
	while( p <= plim ) {
	if( !mark_bit_from_hdr(hhdr, bit_no) ) {
	GC_add_leaked(p);
	}
	p += sz;
	bit_no += MARK_BIT_OFFSET(sz);
	}
	}


	/*
	* Generic procedure to rebuild a free list in hbp.
	* Also called directly from GC_malloc_many.
	* Sz is now in bytes.
	*/
	ptr_t GC_reclaim_generic(struct hblk * hbp, hdr *hhdr, size_t sz,
	GC_bool init, ptr_t list, signed_word *count)
	{
	ptr_t result = list;

	GC_ASSERT(GC_find_header((ptr_t)hbp) == hhdr);
	GC_remove_protection(hbp, 1, (hhdr)->hb_descr == 0 /* Pointer-free? */);
	if (init) {
	result = GC_reclaim_clear(hbp, hhdr, sz, list, count);
	} else {
	GC_ASSERT((hhdr)->hb_descr == 0 /* Pointer-free block */);
	result = GC_reclaim_uninit(hbp, hhdr, sz, list, count);
	}
	if (IS_UNCOLLECTABLE(hhdr -> hb_obj_kind)) GC_set_hdr_marks(hhdr);
	return result;
	}

	/*
	* 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(struct hblk *hbp,
	int report_if_found, signed_word *count)
	{
	hdr *hhdr = HDR(hbp);
	size_t sz = hhdr -> hb_sz;
	int kind = hhdr -> hb_obj_kind;
	struct obj_kind * ok = &GC_obj_kinds[kind];
	void **flh = &(ok -> ok_freelist[BYTES_TO_GRANULES(sz)]);

	hhdr -> hb_last_reclaimed = (unsigned short) GC_gc_no;

	if (report_if_found) {
	GC_reclaim_check(hbp, hhdr, sz);
	} else {
	*flh = GC_reclaim_generic(hbp, hhdr, sz,
	(ok -> ok_init \|\| GC_debugging_started),
	*flh, &GC_bytes_found);
	}
	}

	/*
	* 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 report_if_found is TRUE, then process any block immediately, and
	* simply report free objects; do not actually reclaim them.
	*/
	void GC_reclaim_block(struct hblk *hbp, word report_if_found)
	{
	hdr * hhdr = HDR(hbp);
	size_t sz = hhdr -> hb_sz; /* size of objects in current block */
	struct obj_kind * ok = &GC_obj_kinds[hhdr -> hb_obj_kind];
	struct hblk ** rlh;

	if( sz > MAXOBJBYTES ) { /* 1 big object */
	if( !mark_bit_from_hdr(hhdr, 0) ) {
	if (report_if_found) {
	GC_add_leaked((ptr_t)hbp);
	} else {
	size_t blocks = OBJ_SZ_TO_BLOCKS(sz);
	if (blocks > 1) {
	GC_large_allocd_bytes -= blocks * HBLKSIZE;
	}
	GC_bytes_found += sz;
	GC_freehblk(hbp);
	}
	} else {
	if (hhdr -> hb_descr != 0) {
	GC_composite_in_use += sz;
	} else {
	GC_atomic_in_use += sz;
	}
	}
	} else {
	GC_bool empty = GC_block_empty(hhdr);
	# ifdef PARALLEL_MARK
	/* Count can be low or one too high because we sometimes */
	/* have to ignore decrements. Objects can also potentially */
	/* be repeatedly marked by each marker. */
	/* Here we assume two markers, but this is extremely */
	/* unlikely to fail spuriously with more. And if it does, it */
	/* should be looked at. */
	GC_ASSERT(hhdr -> hb_n_marks <= 2 * (HBLKSIZE/sz + 1) + 16);
	# else
	GC_ASSERT(sz * hhdr -> hb_n_marks <= HBLKSIZE);
	# endif
	if (hhdr -> hb_descr != 0) {
	GC_composite_in_use += sz * hhdr -> hb_n_marks;
	} else {
	GC_atomic_in_use += sz * hhdr -> hb_n_marks;
	}
	if (report_if_found) {
	GC_reclaim_small_nonempty_block(hbp, (int)report_if_found,
	&GC_bytes_found);
	} else if (empty) {
	GC_bytes_found += HBLKSIZE;
	GC_freehblk(hbp);
	} else if (TRUE != GC_block_nearly_full(hhdr)){
	/* group of smaller objects, enqueue the real work */
	rlh = &(ok -> ok_reclaim_list[BYTES_TO_GRANULES(sz)]);
	hhdr -> hb_next = *rlh;
	*rlh = hbp;
	} /* else not worth salvaging. */
	/* We used to do the nearly_full check later, but we */
	/* already have the right cache context here. Also */
	/* doing it here avoids some silly lock contention in */
	/* GC_malloc_many. */
	}
	}

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

	struct Print_stats
	{
	size_t number_of_blocks;
	size_t total_bytes;
	};

	#ifdef USE_MARK_BYTES

	/* Return the number of set mark bits in the given header */
	int GC_n_set_marks(hdr *hhdr)
	{
	int result = 0;
	int i;
	size_t sz = hhdr -> hb_sz;
	int offset = MARK_BIT_OFFSET(sz);
	int limit = FINAL_MARK_BIT(sz);

	for (i = 0; i < limit; i += offset) {
	result += hhdr -> hb_marks[i];
	}
	GC_ASSERT(hhdr -> hb_marks[limit]);
	return(result);
	}

	#else

	/* Number of set bits in a word. Not performance critical. */
	static int set_bits(word n)
	{
	word m = n;
	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(hdr *hhdr)
	{
	int result = 0;
	int i;
	int n_mark_words;
	# ifdef MARK_BIT_PER_OBJ
	int n_objs = HBLK_OBJS(hhdr -> hb_sz);

	if (0 == n_objs) n_objs = 1;
	n_mark_words = divWORDSZ(n_objs + WORDSZ - 1);
	# else /* MARK_BIT_PER_GRANULE */
	n_mark_words = MARK_BITS_SZ;
	# endif
	for (i = 0; i < n_mark_words - 1; i++) {
	result += set_bits(hhdr -> hb_marks[i]);
	}
	# ifdef MARK_BIT_PER_OBJ
	result += set_bits((hhdr -> hb_marks[n_mark_words - 1])
	<< (n_mark_words * WORDSZ - n_objs));
	# else
	result += set_bits(hhdr -> hb_marks[n_mark_words - 1]);
	# endif
	return(result - 1);
	}

	#endif /* !USE_MARK_BYTES */

	/ARGSUSED/
	void GC_print_block_descr(struct hblk h, word / struct PrintStats */ raw_ps)
	{
	hdr * hhdr = HDR(h);
	size_t bytes = hhdr -> hb_sz;
	struct Print_stats *ps;
	unsigned n_marks = GC_n_set_marks(hhdr);

	if (hhdr -> hb_n_marks != n_marks) {
	GC_printf("(%u:%u,%u!=%u)", hhdr -> hb_obj_kind,
	bytes,
	hhdr -> hb_n_marks, n_marks);
	} else {
	GC_printf("(%u:%u,%u)", hhdr -> hb_obj_kind,
	bytes, n_marks);
	}
	bytes += HBLKSIZE-1;
	bytes &= ~(HBLKSIZE-1);

	ps = (struct Print_stats *)raw_ps;
	ps->total_bytes += bytes;
	ps->number_of_blocks++;
	}

	void GC_print_block_list()
	{
	struct Print_stats pstats;

	GC_printf("(kind(0=ptrfree,1=normal,2=unc.):size_in_bytes, #_marks_set)\n");
	pstats.number_of_blocks = 0;
	pstats.total_bytes = 0;
	GC_apply_to_all_blocks(GC_print_block_descr, (word)&pstats);
	GC_printf("\nblocks = %lu, bytes = %lu\n",
	(unsigned long)pstats.number_of_blocks,
	(unsigned long)pstats.total_bytes);
	}

	/* Currently for debugger use only: */
	void GC_print_free_list(int kind, size_t sz_in_granules)
	{
	struct obj_kind * ok = &GC_obj_kinds[kind];
	ptr_t flh = ok -> ok_freelist[sz_in_granules];
	struct hblk *lastBlock = 0;
	int n = 0;

	while (flh){
	struct hblk *block = HBLKPTR(flh);
	if (block != lastBlock){
	GC_printf("\nIn heap block at 0x%x:\n\t", block);
	lastBlock = block;
	}
	GC_printf("%d: 0x%x;", ++n, flh);
	flh = obj_link(flh);
	}
	}

	#endif /* NO_DEBUGGING */

	/*
	* Clear all obj_link pointers in the list of free objects *flp.
	* Clear *flp.
	* This must be done before dropping a list of free gcj-style objects,
	* since may otherwise end up with dangling "descriptor" pointers.
	* It may help for other pointer-containing objects.
	*/
	void GC_clear_fl_links(void **flp)
	{
	void next = flp;

	while (0 != next) {
	*flp = 0;
	flp = &(obj_link(next));
	next = *flp;
	}
	}

	/*
	* Perform GC_reclaim_block on the entire heap, after first clearing
	* small object free lists (if we are not just looking for leaks).
	*/
	void GC_start_reclaim(GC_bool report_if_found)
	{
	unsigned kind;

	# if defined(PARALLEL_MARK) \|\| defined(THREAD_LOCAL_ALLOC)
	GC_ASSERT(0 == GC_fl_builder_count);
	# endif
	/* Reset in use counters. GC_reclaim_block recomputes them. */
	GC_composite_in_use = 0;
	GC_atomic_in_use = 0;
	/* Clear reclaim- and free-lists */
	for (kind = 0; kind < GC_n_kinds; kind++) {
	void **fop;
	void **lim;
	struct hblk ** rlp;
	struct hblk ** rlim;
	struct hblk ** rlist = GC_obj_kinds[kind].ok_reclaim_list;
	GC_bool should_clobber = (GC_obj_kinds[kind].ok_descriptor != 0);

	if (rlist == 0) continue; /* This kind not used. */
	if (!report_if_found) {
	lim = &(GC_obj_kinds[kind].ok_freelist[MAXOBJGRANULES+1]);
	for( fop = GC_obj_kinds[kind].ok_freelist; fop < lim; fop++ ) {
	if (*fop != 0) {
	if (should_clobber) {
	GC_clear_fl_links(fop);
	} else {
	*fop = 0;
	}
	}
	}
	} /* otherwise free list objects are marked, */
	/* and its safe to leave them */
	rlim = rlist + MAXOBJGRANULES+1;
	for( rlp = rlist; rlp < rlim; rlp++ ) {
	*rlp = 0;
	}
	}


	/* 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)report_if_found);

	# ifdef EAGER_SWEEP
	/* This is a very stupid thing to do. We make it possible anyway, */
	/* so that you can convince yourself that it really is very stupid. */
	GC_reclaim_all((GC_stop_func)0, FALSE);
	# endif
	# if defined(PARALLEL_MARK) \|\| defined(THREAD_LOCAL_ALLOC)
	GC_ASSERT(0 == GC_fl_builder_count);
	# endif

	}

	/*
	* 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(size_t sz /* granules */, int kind)
	{
	hdr * hhdr;
	struct hblk * hbp;
	struct obj_kind * ok = &(GC_obj_kinds[kind]);
	struct hblk ** rlh = ok -> ok_reclaim_list;
	void **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, &GC_bytes_found);
	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 reclaim only blocks that have been
	* recently reclaimed, and discard the rest.
	* Stop_func may be 0.
	*/
	GC_bool GC_reclaim_all(GC_stop_func stop_func, GC_bool ignore_old)
	{
	word sz;
	unsigned kind;
	hdr * hhdr;
	struct hblk * hbp;
	struct obj_kind * ok;
	struct hblk ** rlp;
	struct hblk ** rlh;
	CLOCK_TYPE start_time;
	CLOCK_TYPE done_time;

	if (GC_print_stats == VERBOSE)
	GET_TIME(start_time);

	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 <= MAXOBJGRANULES; 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, &GC_bytes_found);
	}
	}
	}
	}
	if (GC_print_stats == VERBOSE) {
	GET_TIME(done_time);
	GC_log_printf("Disposing of reclaim lists took %lu msecs\n",
	MS_TIME_DIFF(done_time,start_time));
	}
	return(TRUE);
	}