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[Emacs-diffs] Changes to emacs/gc/reclaim.c [Boehm-versions]
|
From: |
Dave Love |
|
Subject: |
[Emacs-diffs] Changes to emacs/gc/reclaim.c [Boehm-versions] |
|
Date: |
Mon, 16 Jun 2003 11:20:06 -0400 |
Index: emacs/gc/reclaim.c
diff -c /dev/null emacs/gc/reclaim.c:1.2.2.1.2.1
*** /dev/null Mon Jun 16 11:20:06 2003
--- emacs/gc/reclaim.c Mon Jun 16 11:19:52 2003
***************
*** 0 ****
--- 1,1061 ----
+ /*
+ * 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 by Hewlett-Packard Company. 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.
+ */
+
+ #include <stdio.h>
+ #include "private/gc_priv.h"
+
+ signed_word GC_mem_found = 0;
+ /* Number of words 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(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_printf0("Leaked atomic object at ");
+ } else {
+ GC_err_printf0("Leaked composite object at ");
+ }
+ GC_print_heap_obj(p);
+ GC_err_printf0("\n");
+ GC_free(p);
+ GC_leaked[i] = 0;
+ }
+ GC_n_leaked = 0;
+ printing_errors = FALSE;
+ }
+
+
+ # define FOUND_FREE(hblk, word_no) \
+ { \
+ GC_add_leaked((ptr_t)hblk + WORDS_TO_BYTES(word_no)); \
+ }
+
+ /*
+ * 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;
+ {
+ /* We treat hb_marks as an array of words here, even if it is */
+ /* actually an array of bytes. Since we only check for zero, there
*/
+ /* are no endian-ness issues. */
+ 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);
+ }
+
+ /* The following functions sometimes return a DONT_KNOW value. */
+ #define DONT_KNOW 2
+
+ #ifdef SMALL_CONFIG
+ # define GC_block_nearly_full1(hhdr, pat1) DONT_KNOW
+ # define GC_block_nearly_full3(hhdr, pat1, pat2) DONT_KNOW
+ # define GC_block_nearly_full(hhdr) DONT_KNOW
+ #endif
+
+ #if !defined(SMALL_CONFIG) && defined(USE_MARK_BYTES)
+
+ # define GC_block_nearly_full1(hhdr, pat1) GC_block_nearly_full(hhdr)
+ # define GC_block_nearly_full3(hhdr, pat1, pat2) GC_block_nearly_full(hhdr)
+
+
+ GC_bool GC_block_nearly_full(hhdr)
+ register hdr * hhdr;
+ {
+ /* We again treat hb_marks as an array of words, even though it */
+ /* isn't. We first sum up all the words, resulting in a word */
+ /* containing 4 or 8 separate partial sums. */
+ /* We then sum the bytes in the word of partial sums. */
+ /* This is still endian independant. This fails if the partial */
+ /* sums can overflow. */
+ # if (BYTES_TO_WORDS(MARK_BITS_SZ)) >= 256
+ --> potential overflow; fix the code
+ # endif
+ register word *p = (word *)(&(hhdr -> hb_marks[0]));
+ register word * plim =
+ (word *)(&(hhdr -> hb_marks[MARK_BITS_SZ]));
+ word sum_vector = 0;
+ unsigned sum;
+ while (p < plim) {
+ sum_vector += *p;
+ ++p;
+ }
+ sum = 0;
+ while (sum_vector > 0) {
+ sum += sum_vector & 0xff;
+ sum_vector >>= 8;
+ }
+ return (sum > BYTES_TO_WORDS(7*HBLKSIZE/8)/(hhdr -> hb_sz));
+ }
+ #endif /* USE_MARK_BYTES */
+
+ #if !defined(SMALL_CONFIG) && !defined(USE_MARK_BYTES)
+
+ /*
+ * Test whether nearly all of the mark words consist of the same
+ * repeating pattern.
+ */
+ #define FULL_THRESHOLD (MARK_BITS_SZ/16)
+
+ GC_bool GC_block_nearly_full1(hhdr, pat1)
+ hdr *hhdr;
+ word pat1;
+ {
+ unsigned i;
+ unsigned misses = 0;
+ GC_ASSERT((MARK_BITS_SZ & 1) == 0);
+ for (i = 0; i < MARK_BITS_SZ; ++i) {
+ if ((hhdr -> hb_marks[i] | ~pat1) != ONES) {
+ if (++misses > FULL_THRESHOLD) return FALSE;
+ }
+ }
+ return TRUE;
+ }
+
+ /*
+ * Test whether the same repeating 3 word pattern occurs in nearly
+ * all the mark bit slots.
+ * This is used as a heuristic, so we're a bit sloppy and ignore
+ * the last one or two words.
+ */
+ GC_bool GC_block_nearly_full3(hhdr, pat1, pat2, pat3)
+ hdr *hhdr;
+ word pat1, pat2, pat3;
+ {
+ unsigned i;
+ unsigned misses = 0;
+
+ if (MARK_BITS_SZ < 4) {
+ return DONT_KNOW;
+ }
+ for (i = 0; i < MARK_BITS_SZ - 2; i += 3) {
+ if ((hhdr -> hb_marks[i] | ~pat1) != ONES) {
+ if (++misses > FULL_THRESHOLD) return FALSE;
+ }
+ if ((hhdr -> hb_marks[i+1] | ~pat2) != ONES) {
+ if (++misses > FULL_THRESHOLD) return FALSE;
+ }
+ if ((hhdr -> hb_marks[i+2] | ~pat3) != ONES) {
+ if (++misses > FULL_THRESHOLD) return FALSE;
+ }
+ }
+ return TRUE;
+ }
+
+ /* Check whether a small object block is nearly full by looking at only */
+ /* the mark bits. */
+ /* We manually precomputed the mark bit patterns that need to be */
+ /* checked for, and we give up on the ones that are unlikely to occur,
*/
+ /* or have period > 3.
*/
+ /* This would be a lot easier with a mark bit per object instead of per
*/
+ /* word, but that would rewuire computing object numbers in the mark */
+ /* loop, which would require different data structures ... */
+ GC_bool GC_block_nearly_full(hhdr)
+ hdr *hhdr;
+ {
+ int sz = hhdr -> hb_sz;
+
+ # if CPP_WORDSZ != 32 && CPP_WORDSZ != 64
+ return DONT_KNOW; /* Shouldn't be used in any standard config.
*/
+ # endif
+ # if CPP_WORDSZ == 32
+ switch(sz) {
+ case 1:
+ return GC_block_nearly_full1(hhdr, 0xffffffffl);
+ case 2:
+ return GC_block_nearly_full1(hhdr, 0x55555555l);
+ case 4:
+ return GC_block_nearly_full1(hhdr, 0x11111111l);
+ case 6:
+ return GC_block_nearly_full3(hhdr, 0x41041041l,
+ 0x10410410l,
+ 0x04104104l);
+ case 8:
+ return GC_block_nearly_full1(hhdr, 0x01010101l);
+ case 12:
+ return GC_block_nearly_full3(hhdr, 0x01001001l,
+ 0x10010010l,
+ 0x00100100l);
+ case 16:
+ return GC_block_nearly_full1(hhdr, 0x00010001l);
+ case 32:
+ return GC_block_nearly_full1(hhdr, 0x00000001l);
+ default:
+ return DONT_KNOW;
+ }
+ # endif
+ # if CPP_WORDSZ == 64
+ switch(sz) {
+ case 1:
+ return GC_block_nearly_full1(hhdr, 0xffffffffffffffffl);
+ case 2:
+ return GC_block_nearly_full1(hhdr, 0x5555555555555555l);
+ case 4:
+ return GC_block_nearly_full1(hhdr, 0x1111111111111111l);
+ case 6:
+ return GC_block_nearly_full3(hhdr, 0x1041041041041041l,
+ 0x4104104104104104l,
+ 0x0410410410410410l);
+ case 8:
+ return GC_block_nearly_full1(hhdr, 0x0101010101010101l);
+ case 12:
+ return GC_block_nearly_full3(hhdr, 0x1001001001001001l,
+ 0x0100100100100100l,
+ 0x0010010010010010l);
+ case 16:
+ return GC_block_nearly_full1(hhdr, 0x0001000100010001l);
+ case 32:
+ return GC_block_nearly_full1(hhdr, 0x0000000100000001l);
+ default:
+ return DONT_KNOW;
+ }
+ # endif
+ }
+ #endif /* !SMALL_CONFIG && !USE_MARK_BYTES */
+
+ /* We keep track of reclaimed memory if we are either asked to, or */
+ /* we are using the parallel marker. In the latter case, we assume */
+ /* that most allocation goes through GC_malloc_many for scalability. */
+ /* GC_malloc_many needs the count anyway. */
+ # if defined(GATHERSTATS) || defined(PARALLEL_MARK)
+ # define INCR_WORDS(sz) n_words_found += (sz)
+ # define COUNT_PARAM , count
+ # define COUNT_ARG , count
+ # define COUNT_DECL signed_word * count;
+ # define NWORDS_DECL signed_word n_words_found = 0;
+ # define COUNT_UPDATE *count += n_words_found;
+ # define MEM_FOUND_ADDR , &GC_mem_found
+ # else
+ # define INCR_WORDS(sz)
+ # define COUNT_PARAM
+ # define COUNT_ARG
+ # define COUNT_DECL
+ # define NWORDS_DECL
+ # define COUNT_UPDATE
+ # define MEM_FOUND_ADDR
+ # 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 COUNT_PARAM)
+ register struct hblk *hbp; /* ptr to current heap block */
+ register hdr * hhdr;
+ register ptr_t list;
+ register word sz;
+ COUNT_DECL
+ {
+ register int word_no;
+ register word *p, *q, *plim;
+ NWORDS_DECL
+
+ GC_ASSERT(hhdr == GC_find_header((ptr_t)hbp));
+ p = (word *)(hbp->hb_body);
+ word_no = 0;
+ 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 {
+ 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;
+ # 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
+ }
+ word_no += sz;
+ }
+ COUNT_UPDATE
+ return(list);
+ }
+
+ #if !defined(SMALL_CONFIG) && !defined(USE_MARK_BYTES)
+
+ /*
+ * A special case for 2 word composite objects (e.g. cons cells):
+ */
+ /*ARGSUSED*/
+ ptr_t GC_reclaim_clear2(hbp, hhdr, list COUNT_PARAM)
+ register struct hblk *hbp; /* ptr to current heap block */
+ hdr * hhdr;
+ register ptr_t list;
+ COUNT_DECL
+ {
+ register word * mark_word_addr = &(hhdr->hb_marks[0]);
+ register word *p, *plim;
+ register word mark_word;
+ register int i;
+ NWORDS_DECL
+ # define DO_OBJ(start_displ) \
+ if (!(mark_word & ((word)1 << 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;
+ }
+ }
+ COUNT_UPDATE
+ return(list);
+ # undef DO_OBJ
+ }
+
+ /*
+ * Another special case for 4 word composite objects:
+ */
+ /*ARGSUSED*/
+ ptr_t GC_reclaim_clear4(hbp, hhdr, list COUNT_PARAM)
+ register struct hblk *hbp; /* ptr to current heap block */
+ hdr * hhdr;
+ register ptr_t list;
+ COUNT_DECL
+ {
+ register word * mark_word_addr = &(hhdr->hb_marks[0]);
+ register word *p, *plim;
+ register word mark_word;
+ NWORDS_DECL
+ # define DO_OBJ(start_displ) \
+ if (!(mark_word & ((word)1 << start_displ))) { \
+ p[start_displ] = (word)list; \
+ list = (ptr_t)(p+start_displ); \
+ p[start_displ+1] = 0; \
+ CLEAR_DOUBLE(p + start_displ + 2); \
+ 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;
+ }
+ COUNT_UPDATE
+ return(list);
+ # undef DO_OBJ
+ }
+
+ #endif /* !SMALL_CONFIG && !USE_MARK_BYTES */
+
+ /* The same thing, but don't clear objects: */
+ /*ARGSUSED*/
+ ptr_t GC_reclaim_uninit(hbp, hhdr, sz, list COUNT_PARAM)
+ register struct hblk *hbp; /* ptr to current heap block */
+ register hdr * hhdr;
+ register ptr_t list;
+ register word sz;
+ COUNT_DECL
+ {
+ register int word_no = 0;
+ register word *p, *plim;
+ NWORDS_DECL
+
+ p = (word *)(hbp->hb_body);
+ 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) ) {
+ INCR_WORDS(sz);
+ /* object is available - put on list */
+ obj_link(p) = list;
+ list = ((ptr_t)p);
+ }
+ p += sz;
+ word_no += sz;
+ }
+ COUNT_UPDATE
+ return(list);
+ }
+
+ /* Don't really reclaim objects, just check for unmarked ones: */
+ /*ARGSUSED*/
+ void GC_reclaim_check(hbp, hhdr, sz)
+ register struct hblk *hbp; /* ptr to current heap block */
+ register hdr * hhdr;
+ register word sz;
+ {
+ register int word_no = 0;
+ register word *p, *plim;
+ # ifdef GATHERSTATS
+ register int n_words_found = 0;
+ # endif
+
+ p = (word *)(hbp->hb_body);
+ 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);
+ }
+ p += sz;
+ word_no += sz;
+ }
+ }
+
+ #if !defined(SMALL_CONFIG) && !defined(USE_MARK_BYTES)
+ /*
+ * Another special case for 2 word atomic objects:
+ */
+ /*ARGSUSED*/
+ ptr_t GC_reclaim_uninit2(hbp, hhdr, list COUNT_PARAM)
+ register struct hblk *hbp; /* ptr to current heap block */
+ hdr * hhdr;
+ register ptr_t list;
+ COUNT_DECL
+ {
+ register word * mark_word_addr = &(hhdr->hb_marks[0]);
+ register word *p, *plim;
+ register word mark_word;
+ register int i;
+ NWORDS_DECL
+ # define DO_OBJ(start_displ) \
+ if (!(mark_word & ((word)1 << 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;
+ }
+ }
+ COUNT_UPDATE
+ return(list);
+ # undef DO_OBJ
+ }
+
+ /*
+ * Another special case for 4 word atomic objects:
+ */
+ /*ARGSUSED*/
+ ptr_t GC_reclaim_uninit4(hbp, hhdr, list COUNT_PARAM)
+ register struct hblk *hbp; /* ptr to current heap block */
+ hdr * hhdr;
+ register ptr_t list;
+ COUNT_DECL
+ {
+ register word * mark_word_addr = &(hhdr->hb_marks[0]);
+ register word *p, *plim;
+ register word mark_word;
+ NWORDS_DECL
+ # define DO_OBJ(start_displ) \
+ if (!(mark_word & ((word)1 << 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;
+ }
+ COUNT_UPDATE
+ return(list);
+ # undef DO_OBJ
+ }
+
+ /* Finally the one word case, which never requires any clearing: */
+ /*ARGSUSED*/
+ ptr_t GC_reclaim1(hbp, hhdr, list COUNT_PARAM)
+ register struct hblk *hbp; /* ptr to current heap block */
+ hdr * hhdr;
+ register ptr_t list;
+ COUNT_DECL
+ {
+ register word * mark_word_addr = &(hhdr->hb_marks[0]);
+ register word *p, *plim;
+ register word mark_word;
+ register int i;
+ NWORDS_DECL
+ # define DO_OBJ(start_displ) \
+ if (!(mark_word & ((word)1 << 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;
+ }
+ }
+ COUNT_UPDATE
+ return(list);
+ # undef DO_OBJ
+ }
+
+ #endif /* !SMALL_CONFIG && !USE_MARK_BYTES */
+
+ /*
+ * Generic procedure to rebuild a free list in hbp.
+ * Also called directly from GC_malloc_many.
+ */
+ ptr_t GC_reclaim_generic(hbp, hhdr, sz, init, list COUNT_PARAM)
+ struct hblk *hbp; /* ptr to current heap block */
+ hdr * hhdr;
+ GC_bool init;
+ ptr_t list;
+ word sz;
+ COUNT_DECL
+ {
+ 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) {
+ switch(sz) {
+ # if !defined(SMALL_CONFIG) && !defined(USE_MARK_BYTES)
+ case 1:
+ /* We now issue the hint even if GC_nearly_full returned */
+ /* DONT_KNOW. */
+ result = GC_reclaim1(hbp, hhdr, list COUNT_ARG);
+ break;
+ case 2:
+ result = GC_reclaim_clear2(hbp, hhdr, list COUNT_ARG);
+ break;
+ case 4:
+ result = GC_reclaim_clear4(hbp, hhdr, list COUNT_ARG);
+ break;
+ # endif /* !SMALL_CONFIG && !USE_MARK_BYTES */
+ default:
+ result = GC_reclaim_clear(hbp, hhdr, sz, list COUNT_ARG);
+ break;
+ }
+ } else {
+ GC_ASSERT((hhdr)->hb_descr == 0 /* Pointer-free block */);
+ switch(sz) {
+ # if !defined(SMALL_CONFIG) && !defined(USE_MARK_BYTES)
+ case 1:
+ result = GC_reclaim1(hbp, hhdr, list COUNT_ARG);
+ break;
+ case 2:
+ result = GC_reclaim_uninit2(hbp, hhdr, list COUNT_ARG);
+ break;
+ case 4:
+ result = GC_reclaim_uninit4(hbp, hhdr, list COUNT_ARG);
+ break;
+ # endif /* !SMALL_CONFIG && !USE_MARK_BYTES */
+ default:
+ result = GC_reclaim_uninit(hbp, hhdr, sz, list COUNT_ARG);
+ break;
+ }
+ }
+ 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(hbp, report_if_found COUNT_PARAM)
+ register struct hblk *hbp; /* ptr to current heap block */
+ int report_if_found; /* Abort if a reclaimable object is found */
+ COUNT_DECL
+ {
+ hdr *hhdr = HDR(hbp);
+ word sz = hhdr -> hb_sz;
+ int kind = hhdr -> hb_obj_kind;
+ struct obj_kind * ok = &GC_obj_kinds[kind];
+ ptr_t * flh = &(ok -> ok_freelist[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 MEM_FOUND_ADDR);
+ }
+ }
+
+ /*
+ * 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.
+ */
+ # if defined(__STDC__) || defined(__cplusplus)
+ void GC_reclaim_block(register struct hblk *hbp, word report_if_found)
+ # else
+ void GC_reclaim_block(hbp, report_if_found)
+ register struct hblk *hbp; /* ptr to current heap block
*/
+ word report_if_found; /* Abort if a reclaimable object is found */
+ # endif
+ {
+ 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, 0) ) {
+ if (report_if_found) {
+ FOUND_FREE(hbp, 0);
+ } else {
+ word blocks = OBJ_SZ_TO_BLOCKS(sz);
+ if (blocks > 1) {
+ GC_large_allocd_bytes -= blocks * HBLKSIZE;
+ }
+ # ifdef GATHERSTATS
+ GC_mem_found += sz;
+ # endif
+ GC_freehblk(hbp);
+ }
+ }
+ } else {
+ GC_bool empty = GC_block_empty(hhdr);
+ if (report_if_found) {
+ GC_reclaim_small_nonempty_block(hbp, (int)report_if_found
+ MEM_FOUND_ADDR);
+ } else if (empty) {
+ # ifdef GATHERSTATS
+ GC_mem_found += BYTES_TO_WORDS(HBLKSIZE);
+ # endif
+ GC_freehblk(hbp);
+ } else if (TRUE != GC_block_nearly_full(hhdr)){
+ /* group of smaller objects, enqueue the real work */
+ rlh = &(ok -> ok_reclaim_list[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(hhdr)
+ hdr * hhdr;
+ {
+ register int result = 0;
+ register int i;
+
+ for (i = 0; i < MARK_BITS_SZ; i++) {
+ result += hhdr -> hb_marks[i];
+ }
+ return(result);
+ }
+
+ #else
+
+ /* 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);
+ }
+
+ #endif /* !USE_MARK_BYTES */
+
+ /*ARGSUSED*/
+ # if defined(__STDC__) || defined(__cplusplus)
+ void GC_print_block_descr(struct hblk *h, word dummy)
+ # else
+ void GC_print_block_descr(h, dummy)
+ struct hblk *h;
+ word dummy;
+ # endif
+ {
+ register hdr * hhdr = HDR(h);
+ register size_t bytes = WORDS_TO_BYTES(hhdr -> hb_sz);
+ struct Print_stats *ps;
+
+ GC_printf3("(%lu:%lu,%lu)", (unsigned long)(hhdr -> hb_obj_kind),
+ (unsigned long)bytes,
+ (unsigned long)(GC_n_set_marks(hhdr)));
+ bytes += HBLKSIZE-1;
+ bytes &= ~(HBLKSIZE-1);
+
+ ps = (struct Print_stats *)dummy;
+ ps->total_bytes += bytes;
+ ps->number_of_blocks++;
+ }
+
+ void GC_print_block_list()
+ {
+ struct Print_stats pstats;
+
+ GC_printf0("(kind(0=ptrfree,1=normal,2=unc.,3=stubborn):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_printf2("\nblocks = %lu, bytes = %lu\n",
+ (unsigned long)pstats.number_of_blocks,
+ (unsigned long)pstats.total_bytes);
+ }
+
+ #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(flp)
+ ptr_t *flp;
+ {
+ ptr_t 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(report_if_found)
+ int report_if_found; /* Abort if a GC_reclaimable object is found */
+ {
+ int kind;
+
+ # if defined(PARALLEL_MARK) || defined(THREAD_LOCAL_ALLOC)
+ GC_ASSERT(0 == GC_fl_builder_count);
+ # endif
+ /* Clear reclaim- and free-lists */
+ for (kind = 0; kind < GC_n_kinds; kind++) {
+ ptr_t *fop;
+ ptr_t *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[MAXOBJSZ+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 + 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)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(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 MEM_FOUND_ADDR);
+ 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(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 MEM_FOUND_ADDR);
+ }
+ }
+ }
+ }
+ # 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);
+ }
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