diff options
Diffstat (limited to 'boehm-gc/reclaim.c')
| -rw-r--r-- | boehm-gc/reclaim.c | 723 |
1 files changed, 0 insertions, 723 deletions
diff --git a/boehm-gc/reclaim.c b/boehm-gc/reclaim.c deleted file mode 100644 index 407b4c68194..00000000000 --- a/boehm-gc/reclaim.c +++ /dev/null @@ -1,723 +0,0 @@ -/* - * 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); -} |