+++ /dev/null
-/*
- * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
- * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
- * Copyright (c) 1998-1999 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.
- */
-
-/* #define DEBUG */
-#include <stdio.h>
-#include "private/gc_priv.h"
-
-GC_bool GC_use_entire_heap = 0;
-
-/*
- * Free heap blocks are kept on one of several free lists,
- * depending on the size of the block. Each free list is doubly linked.
- * Adjacent free blocks are coalesced.
- */
-
-
-# define MAX_BLACK_LIST_ALLOC (2*HBLKSIZE)
- /* largest block we will allocate starting on a black */
- /* listed block. Must be >= HBLKSIZE. */
-
-
-# define UNIQUE_THRESHOLD 32
- /* Sizes up to this many HBLKs each have their own free list */
-# define HUGE_THRESHOLD 256
- /* Sizes of at least this many heap blocks are mapped to a */
- /* single free list. */
-# define FL_COMPRESSION 8
- /* In between sizes map this many distinct sizes to a single */
- /* bin. */
-
-# define N_HBLK_FLS (HUGE_THRESHOLD - UNIQUE_THRESHOLD)/FL_COMPRESSION \
- + UNIQUE_THRESHOLD
-
-struct hblk * GC_hblkfreelist[N_HBLK_FLS+1] = { 0 };
-
-#ifndef USE_MUNMAP
- word GC_free_bytes[N_HBLK_FLS+1] = { 0 };
- /* Number of free bytes on each list. */
-
- /* Is bytes + the number of free bytes on lists n .. N_HBLK_FLS */
- /* > GC_max_large_allocd_bytes? */
- GC_bool GC_enough_large_bytes_left(bytes,n)
- word bytes;
- int n;
- {
- int i;
- for (i = N_HBLK_FLS; i >= n; --i) {
- bytes += GC_free_bytes[i];
- if (bytes > GC_max_large_allocd_bytes) return TRUE;
- }
- return FALSE;
- }
-
-# define INCR_FREE_BYTES(n, b) GC_free_bytes[n] += (b);
-
-# define FREE_ASSERT(e) GC_ASSERT(e)
-
-#else /* USE_MUNMAP */
-
-# define INCR_FREE_BYTES(n, b)
-# define FREE_ASSERT(e)
-
-#endif /* USE_MUNMAP */
-
-/* Map a number of blocks to the appropriate large block free list index. */
-int GC_hblk_fl_from_blocks(blocks_needed)
-word blocks_needed;
-{
- if (blocks_needed <= UNIQUE_THRESHOLD) return blocks_needed;
- if (blocks_needed >= HUGE_THRESHOLD) return N_HBLK_FLS;
- return (blocks_needed - UNIQUE_THRESHOLD)/FL_COMPRESSION
- + UNIQUE_THRESHOLD;
-
-}
-
-# define PHDR(hhdr) HDR(hhdr -> hb_prev)
-# define NHDR(hhdr) HDR(hhdr -> hb_next)
-
-# ifdef USE_MUNMAP
-# define IS_MAPPED(hhdr) (((hhdr) -> hb_flags & WAS_UNMAPPED) == 0)
-# else /* !USE_MMAP */
-# define IS_MAPPED(hhdr) 1
-# endif /* USE_MUNMAP */
-
-# if !defined(NO_DEBUGGING)
-void GC_print_hblkfreelist()
-{
- struct hblk * h;
- word total_free = 0;
- hdr * hhdr;
- word sz;
- int i;
-
- for (i = 0; i <= N_HBLK_FLS; ++i) {
- h = GC_hblkfreelist[i];
-# ifdef USE_MUNMAP
- if (0 != h) GC_printf1("Free list %ld (Total size %ld):\n",
- (unsigned long)i);
-# else
- if (0 != h) GC_printf2("Free list %ld (Total size %ld):\n",
- (unsigned long)i,
- (unsigned long)GC_free_bytes[i]);
-# endif
- while (h != 0) {
- hhdr = HDR(h);
- sz = hhdr -> hb_sz;
- GC_printf2("\t0x%lx size %lu ", (unsigned long)h, (unsigned long)sz);
- total_free += sz;
- if (GC_is_black_listed(h, HBLKSIZE) != 0) {
- GC_printf0("start black listed\n");
- } else if (GC_is_black_listed(h, hhdr -> hb_sz) != 0) {
- GC_printf0("partially black listed\n");
- } else {
- GC_printf0("not black listed\n");
- }
- h = hhdr -> hb_next;
- }
- }
- if (total_free != GC_large_free_bytes) {
- GC_printf1("GC_large_free_bytes = %lu (INCONSISTENT!!)\n",
- (unsigned long) GC_large_free_bytes);
- }
- GC_printf1("Total of %lu bytes on free list\n", (unsigned long)total_free);
-}
-
-/* Return the free list index on which the block described by the header */
-/* appears, or -1 if it appears nowhere. */
-int free_list_index_of(wanted)
-hdr * wanted;
-{
- struct hblk * h;
- hdr * hhdr;
- int i;
-
- for (i = 0; i <= N_HBLK_FLS; ++i) {
- h = GC_hblkfreelist[i];
- while (h != 0) {
- hhdr = HDR(h);
- if (hhdr == wanted) return i;
- h = hhdr -> hb_next;
- }
- }
- return -1;
-}
-
-void GC_dump_regions()
-{
- unsigned i;
- ptr_t start, end;
- ptr_t p;
- size_t bytes;
- hdr *hhdr;
- for (i = 0; i < GC_n_heap_sects; ++i) {
- start = GC_heap_sects[i].hs_start;
- bytes = GC_heap_sects[i].hs_bytes;
- end = start + bytes;
- /* Merge in contiguous sections. */
- while (i+1 < GC_n_heap_sects && GC_heap_sects[i+1].hs_start == end) {
- ++i;
- end = GC_heap_sects[i].hs_start + GC_heap_sects[i].hs_bytes;
- }
- GC_printf2("***Section from 0x%lx to 0x%lx\n", start, end);
- for (p = start; p < end;) {
- hhdr = HDR(p);
- GC_printf1("\t0x%lx ", (unsigned long)p);
- if (IS_FORWARDING_ADDR_OR_NIL(hhdr)) {
- GC_printf1("Missing header!!\n", hhdr);
- p += HBLKSIZE;
- continue;
- }
- if (HBLK_IS_FREE(hhdr)) {
- int correct_index = GC_hblk_fl_from_blocks(
- divHBLKSZ(hhdr -> hb_sz));
- int actual_index;
-
- GC_printf1("\tfree block of size 0x%lx bytes",
- (unsigned long)(hhdr -> hb_sz));
- if (IS_MAPPED(hhdr)) {
- GC_printf0("\n");
- } else {
- GC_printf0("(unmapped)\n");
- }
- actual_index = free_list_index_of(hhdr);
- if (-1 == actual_index) {
- GC_printf1("\t\tBlock not on free list %ld!!\n",
- correct_index);
- } else if (correct_index != actual_index) {
- GC_printf2("\t\tBlock on list %ld, should be on %ld!!\n",
- actual_index, correct_index);
- }
- p += hhdr -> hb_sz;
- } else {
- GC_printf1("\tused for blocks of size 0x%lx bytes\n",
- (unsigned long)WORDS_TO_BYTES(hhdr -> hb_sz));
- p += HBLKSIZE * OBJ_SZ_TO_BLOCKS(hhdr -> hb_sz);
- }
- }
- }
-}
-
-# endif /* NO_DEBUGGING */
-
-/* Initialize hdr for a block containing the indicated size and */
-/* kind of objects. */
-/* Return FALSE on failure. */
-static GC_bool setup_header(hhdr, sz, kind, flags)
-register hdr * hhdr;
-word sz; /* object size in words */
-int kind;
-unsigned char flags;
-{
- register word descr;
-
- /* Add description of valid object pointers */
- if (!GC_add_map_entry(sz)) return(FALSE);
- hhdr -> hb_map = GC_obj_map[sz > MAXOBJSZ? 0 : sz];
-
- /* Set size, kind and mark proc fields */
- hhdr -> hb_sz = sz;
- hhdr -> hb_obj_kind = kind;
- hhdr -> hb_flags = flags;
- descr = GC_obj_kinds[kind].ok_descriptor;
- if (GC_obj_kinds[kind].ok_relocate_descr) descr += WORDS_TO_BYTES(sz);
- hhdr -> hb_descr = descr;
-
- /* Clear mark bits */
- GC_clear_hdr_marks(hhdr);
-
- hhdr -> hb_last_reclaimed = (unsigned short)GC_gc_no;
- return(TRUE);
-}
-
-#define FL_UNKNOWN -1
-/*
- * Remove hhdr from the appropriate free list.
- * We assume it is on the nth free list, or on the size
- * appropriate free list if n is FL_UNKNOWN.
- */
-void GC_remove_from_fl(hhdr, n)
-hdr * hhdr;
-int n;
-{
- int index;
-
- GC_ASSERT(((hhdr -> hb_sz) & (HBLKSIZE-1)) == 0);
-# ifndef USE_MUNMAP
- /* We always need index to mainatin free counts. */
- if (FL_UNKNOWN == n) {
- index = GC_hblk_fl_from_blocks(divHBLKSZ(hhdr -> hb_sz));
- } else {
- index = n;
- }
-# endif
- if (hhdr -> hb_prev == 0) {
-# ifdef USE_MUNMAP
- if (FL_UNKNOWN == n) {
- index = GC_hblk_fl_from_blocks(divHBLKSZ(hhdr -> hb_sz));
- } else {
- index = n;
- }
-# endif
- GC_ASSERT(HDR(GC_hblkfreelist[index]) == hhdr);
- GC_hblkfreelist[index] = hhdr -> hb_next;
- } else {
- hdr *phdr;
- GET_HDR(hhdr -> hb_prev, phdr);
- phdr -> hb_next = hhdr -> hb_next;
- }
- INCR_FREE_BYTES(index, - (signed_word)(hhdr -> hb_sz));
- FREE_ASSERT(GC_free_bytes[index] >= 0);
- if (0 != hhdr -> hb_next) {
- hdr * nhdr;
- GC_ASSERT(!IS_FORWARDING_ADDR_OR_NIL(NHDR(hhdr)));
- GET_HDR(hhdr -> hb_next, nhdr);
- nhdr -> hb_prev = hhdr -> hb_prev;
- }
-}
-
-/*
- * Return a pointer to the free block ending just before h, if any.
- */
-struct hblk * GC_free_block_ending_at(h)
-struct hblk *h;
-{
- struct hblk * p = h - 1;
- hdr * phdr;
-
- GET_HDR(p, phdr);
- while (0 != phdr && IS_FORWARDING_ADDR_OR_NIL(phdr)) {
- p = FORWARDED_ADDR(p,phdr);
- phdr = HDR(p);
- }
- if (0 != phdr) {
- if(HBLK_IS_FREE(phdr)) {
- return p;
- } else {
- return 0;
- }
- }
- p = GC_prev_block(h - 1);
- if (0 != p) {
- phdr = HDR(p);
- if (HBLK_IS_FREE(phdr) && (ptr_t)p + phdr -> hb_sz == (ptr_t)h) {
- return p;
- }
- }
- return 0;
-}
-
-/*
- * Add hhdr to the appropriate free list.
- * We maintain individual free lists sorted by address.
- */
-void GC_add_to_fl(h, hhdr)
-struct hblk *h;
-hdr * hhdr;
-{
- int index = GC_hblk_fl_from_blocks(divHBLKSZ(hhdr -> hb_sz));
- struct hblk *second = GC_hblkfreelist[index];
- hdr * second_hdr;
-# ifdef GC_ASSERTIONS
- struct hblk *next = (struct hblk *)((word)h + hhdr -> hb_sz);
- hdr * nexthdr = HDR(next);
- struct hblk *prev = GC_free_block_ending_at(h);
- hdr * prevhdr = HDR(prev);
- GC_ASSERT(nexthdr == 0 || !HBLK_IS_FREE(nexthdr) || !IS_MAPPED(nexthdr));
- GC_ASSERT(prev == 0 || !HBLK_IS_FREE(prevhdr) || !IS_MAPPED(prevhdr));
-# endif
- GC_ASSERT(((hhdr -> hb_sz) & (HBLKSIZE-1)) == 0);
- GC_hblkfreelist[index] = h;
- INCR_FREE_BYTES(index, hhdr -> hb_sz);
- FREE_ASSERT(GC_free_bytes[index] <= GC_large_free_bytes)
- hhdr -> hb_next = second;
- hhdr -> hb_prev = 0;
- if (0 != second) {
- GET_HDR(second, second_hdr);
- second_hdr -> hb_prev = h;
- }
- GC_invalidate_map(hhdr);
-}
-
-#ifdef USE_MUNMAP
-
-/* Unmap blocks that haven't been recently touched. This is the only way */
-/* way blocks are ever unmapped. */
-void GC_unmap_old(void)
-{
- struct hblk * h;
- hdr * hhdr;
- word sz;
- unsigned short last_rec, threshold;
- int i;
-# define UNMAP_THRESHOLD 6
-
- for (i = 0; i <= N_HBLK_FLS; ++i) {
- for (h = GC_hblkfreelist[i]; 0 != h; h = hhdr -> hb_next) {
- hhdr = HDR(h);
- if (!IS_MAPPED(hhdr)) continue;
- threshold = (unsigned short)(GC_gc_no - UNMAP_THRESHOLD);
- last_rec = hhdr -> hb_last_reclaimed;
- if (last_rec > GC_gc_no
- || last_rec < threshold && threshold < GC_gc_no
- /* not recently wrapped */) {
- sz = hhdr -> hb_sz;
- GC_unmap((ptr_t)h, sz);
- hhdr -> hb_flags |= WAS_UNMAPPED;
- }
- }
- }
-}
-
-/* Merge all unmapped blocks that are adjacent to other free */
-/* blocks. This may involve remapping, since all blocks are either */
-/* fully mapped or fully unmapped. */
-void GC_merge_unmapped(void)
-{
- struct hblk * h, *next;
- hdr * hhdr, *nexthdr;
- word size, nextsize;
- int i;
-
- for (i = 0; i <= N_HBLK_FLS; ++i) {
- h = GC_hblkfreelist[i];
- while (h != 0) {
- GET_HDR(h, hhdr);
- size = hhdr->hb_sz;
- next = (struct hblk *)((word)h + size);
- GET_HDR(next, nexthdr);
- /* Coalesce with successor, if possible */
- if (0 != nexthdr && HBLK_IS_FREE(nexthdr)) {
- nextsize = nexthdr -> hb_sz;
- if (IS_MAPPED(hhdr)) {
- GC_ASSERT(!IS_MAPPED(nexthdr));
- /* make both consistent, so that we can merge */
- if (size > nextsize) {
- GC_remap((ptr_t)next, nextsize);
- } else {
- GC_unmap((ptr_t)h, size);
- hhdr -> hb_flags |= WAS_UNMAPPED;
- }
- } else if (IS_MAPPED(nexthdr)) {
- GC_ASSERT(!IS_MAPPED(hhdr));
- if (size > nextsize) {
- GC_unmap((ptr_t)next, nextsize);
- } else {
- GC_remap((ptr_t)h, size);
- hhdr -> hb_flags &= ~WAS_UNMAPPED;
- }
- } else {
- /* Unmap any gap in the middle */
- GC_unmap_gap((ptr_t)h, size, (ptr_t)next, nexthdr -> hb_sz);
- }
- /* If they are both unmapped, we merge, but leave unmapped. */
- GC_remove_from_fl(hhdr, i);
- GC_remove_from_fl(nexthdr, FL_UNKNOWN);
- hhdr -> hb_sz += nexthdr -> hb_sz;
- GC_remove_header(next);
- GC_add_to_fl(h, hhdr);
- /* Start over at beginning of list */
- h = GC_hblkfreelist[i];
- } else /* not mergable with successor */ {
- h = hhdr -> hb_next;
- }
- } /* while (h != 0) ... */
- } /* for ... */
-}
-
-#endif /* USE_MUNMAP */
-
-/*
- * Return a pointer to a block starting at h of length bytes.
- * Memory for the block is mapped.
- * Remove the block from its free list, and return the remainder (if any)
- * to its appropriate free list.
- * May fail by returning 0.
- * The header for the returned block must be set up by the caller.
- * If the return value is not 0, then hhdr is the header for it.
- */
-struct hblk * GC_get_first_part(h, hhdr, bytes, index)
-struct hblk *h;
-hdr * hhdr;
-word bytes;
-int index;
-{
- word total_size = hhdr -> hb_sz;
- struct hblk * rest;
- hdr * rest_hdr;
-
- GC_ASSERT((total_size & (HBLKSIZE-1)) == 0);
- GC_remove_from_fl(hhdr, index);
- if (total_size == bytes) return h;
- rest = (struct hblk *)((word)h + bytes);
- rest_hdr = GC_install_header(rest);
- if (0 == rest_hdr) return(0);
- rest_hdr -> hb_sz = total_size - bytes;
- rest_hdr -> hb_flags = 0;
-# ifdef GC_ASSERTIONS
- /* Mark h not free, to avoid assertion about adjacent free blocks. */
- hhdr -> hb_map = 0;
-# endif
- GC_add_to_fl(rest, rest_hdr);
- return h;
-}
-
-/*
- * H is a free block. N points at an address inside it.
- * A new header for n has already been set up. Fix up h's header
- * to reflect the fact that it is being split, move it to the
- * appropriate free list.
- * N replaces h in the original free list.
- *
- * Nhdr is not completely filled in, since it is about to allocated.
- * It may in fact end up on the wrong free list for its size.
- * (Hence adding it to a free list is silly. But this path is hopefully
- * rare enough that it doesn't matter. The code is cleaner this way.)
- */
-void GC_split_block(h, hhdr, n, nhdr, index)
-struct hblk *h;
-hdr * hhdr;
-struct hblk *n;
-hdr * nhdr;
-int index; /* Index of free list */
-{
- word total_size = hhdr -> hb_sz;
- word h_size = (word)n - (word)h;
- struct hblk *prev = hhdr -> hb_prev;
- struct hblk *next = hhdr -> hb_next;
-
- /* Replace h with n on its freelist */
- nhdr -> hb_prev = prev;
- nhdr -> hb_next = next;
- nhdr -> hb_sz = total_size - h_size;
- nhdr -> hb_flags = 0;
- if (0 != prev) {
- HDR(prev) -> hb_next = n;
- } else {
- GC_hblkfreelist[index] = n;
- }
- if (0 != next) {
- HDR(next) -> hb_prev = n;
- }
- INCR_FREE_BYTES(index, -(signed_word)h_size);
- FREE_ASSERT(GC_free_bytes[index] > 0);
-# ifdef GC_ASSERTIONS
- nhdr -> hb_map = 0; /* Don't fail test for consecutive */
- /* free blocks in GC_add_to_fl. */
-# endif
-# ifdef USE_MUNMAP
- hhdr -> hb_last_reclaimed = GC_gc_no;
-# endif
- hhdr -> hb_sz = h_size;
- GC_add_to_fl(h, hhdr);
- GC_invalidate_map(nhdr);
-}
-
-struct hblk * GC_allochblk_nth();
-
-/*
- * Allocate (and return pointer to) a heap block
- * for objects of size sz words, searching the nth free list.
- *
- * NOTE: We set obj_map field in header correctly.
- * Caller is responsible for building an object freelist in block.
- *
- * Unlike older versions of the collectors, the client is responsible
- * for clearing the block, if necessary.
- */
-struct hblk *
-GC_allochblk(sz, kind, flags)
-word sz;
-int kind;
-unsigned flags; /* IGNORE_OFF_PAGE or 0 */
-{
- word blocks = OBJ_SZ_TO_BLOCKS(sz);
- int start_list = GC_hblk_fl_from_blocks(blocks);
- int i;
- for (i = start_list; i <= N_HBLK_FLS; ++i) {
- struct hblk * result = GC_allochblk_nth(sz, kind, flags, i);
- if (0 != result) {
- return result;
- }
- }
- return 0;
-}
-/*
- * The same, but with search restricted to nth free list.
- */
-struct hblk *
-GC_allochblk_nth(sz, kind, flags, n)
-word sz;
-int kind;
-unsigned char flags; /* IGNORE_OFF_PAGE or 0 */
-int n;
-{
- register struct hblk *hbp;
- register hdr * hhdr; /* Header corr. to hbp */
- register struct hblk *thishbp;
- register hdr * thishdr; /* Header corr. to hbp */
- signed_word size_needed; /* number of bytes in requested objects */
- signed_word size_avail; /* bytes available in this block */
-
- size_needed = HBLKSIZE * OBJ_SZ_TO_BLOCKS(sz);
-
- /* search for a big enough block in free list */
- hbp = GC_hblkfreelist[n];
- for(; 0 != hbp; hbp = hhdr -> hb_next) {
- GET_HDR(hbp, hhdr);
- size_avail = hhdr->hb_sz;
- if (size_avail < size_needed) continue;
- if (!GC_use_entire_heap
- && size_avail != size_needed
- && USED_HEAP_SIZE >= GC_requested_heapsize
- && !GC_incremental && GC_should_collect()) {
-# ifdef USE_MUNMAP
- continue;
-# else
- /* If we enough large blocks left to cover any */
- /* previous request for large blocks, we go ahead */
- /* and split. Assuming a steady state, that should */
- /* be safe. It means that we can use the full */
- /* heap if we allocate only small objects. */
- if (!GC_enough_large_bytes_left(GC_large_allocd_bytes, n)) {
- continue;
- }
-# endif /* !USE_MUNMAP */
- }
- /* If the next heap block is obviously better, go on. */
- /* This prevents us from disassembling a single large block */
- /* to get tiny blocks. */
- {
- signed_word next_size;
-
- thishbp = hhdr -> hb_next;
- if (thishbp != 0) {
- GET_HDR(thishbp, thishdr);
- next_size = (signed_word)(thishdr -> hb_sz);
- if (next_size < size_avail
- && next_size >= size_needed
- && !GC_is_black_listed(thishbp, (word)size_needed)) {
- continue;
- }
- }
- }
- if ( !IS_UNCOLLECTABLE(kind) &&
- (kind != PTRFREE || size_needed > MAX_BLACK_LIST_ALLOC)) {
- struct hblk * lasthbp = hbp;
- ptr_t search_end = (ptr_t)hbp + size_avail - size_needed;
- signed_word orig_avail = size_avail;
- signed_word eff_size_needed = ((flags & IGNORE_OFF_PAGE)?
- HBLKSIZE
- : size_needed);
-
-
- while ((ptr_t)lasthbp <= search_end
- && (thishbp = GC_is_black_listed(lasthbp,
- (word)eff_size_needed))
- != 0) {
- lasthbp = thishbp;
- }
- size_avail -= (ptr_t)lasthbp - (ptr_t)hbp;
- thishbp = lasthbp;
- if (size_avail >= size_needed) {
- if (thishbp != hbp &&
- 0 != (thishdr = GC_install_header(thishbp))) {
- /* Make sure it's mapped before we mangle it. */
-# ifdef USE_MUNMAP
- if (!IS_MAPPED(hhdr)) {
- GC_remap((ptr_t)hbp, hhdr -> hb_sz);
- hhdr -> hb_flags &= ~WAS_UNMAPPED;
- }
-# endif
- /* Split the block at thishbp */
- GC_split_block(hbp, hhdr, thishbp, thishdr, n);
- /* Advance to thishbp */
- hbp = thishbp;
- hhdr = thishdr;
- /* We must now allocate thishbp, since it may */
- /* be on the wrong free list. */
- }
- } else if (size_needed > (signed_word)BL_LIMIT
- && orig_avail - size_needed
- > (signed_word)BL_LIMIT) {
- /* Punt, since anything else risks unreasonable heap growth. */
- if (++GC_large_alloc_warn_suppressed
- >= GC_large_alloc_warn_interval) {
- WARN("Repeated allocation of very large block "
- "(appr. size %ld):\n"
- "\tMay lead to memory leak and poor performance.\n",
- size_needed);
- GC_large_alloc_warn_suppressed = 0;
- }
- size_avail = orig_avail;
- } else if (size_avail == 0 && size_needed == HBLKSIZE
- && IS_MAPPED(hhdr)) {
- if (!GC_find_leak) {
- static unsigned count = 0;
-
- /* The block is completely blacklisted. We need */
- /* to drop some such blocks, since otherwise we spend */
- /* all our time traversing them if pointerfree */
- /* blocks are unpopular. */
- /* A dropped block will be reconsidered at next GC. */
- if ((++count & 3) == 0) {
- /* Allocate and drop the block in small chunks, to */
- /* maximize the chance that we will recover some */
- /* later. */
- word total_size = hhdr -> hb_sz;
- struct hblk * limit = hbp + divHBLKSZ(total_size);
- struct hblk * h;
- struct hblk * prev = hhdr -> hb_prev;
-
- GC_words_wasted += total_size;
- GC_large_free_bytes -= total_size;
- GC_remove_from_fl(hhdr, n);
- for (h = hbp; h < limit; h++) {
- if (h == hbp || 0 != (hhdr = GC_install_header(h))) {
- (void) setup_header(
- hhdr,
- BYTES_TO_WORDS(HBLKSIZE),
- PTRFREE, 0); /* Cant fail */
- if (GC_debugging_started) {
- BZERO(h, HBLKSIZE);
- }
- }
- }
- /* Restore hbp to point at free block */
- hbp = prev;
- if (0 == hbp) {
- return GC_allochblk_nth(sz, kind, flags, n);
- }
- hhdr = HDR(hbp);
- }
- }
- }
- }
- if( size_avail >= size_needed ) {
-# ifdef USE_MUNMAP
- if (!IS_MAPPED(hhdr)) {
- GC_remap((ptr_t)hbp, hhdr -> hb_sz);
- hhdr -> hb_flags &= ~WAS_UNMAPPED;
- }
-# endif
- /* hbp may be on the wrong freelist; the parameter n */
- /* is important. */
- hbp = GC_get_first_part(hbp, hhdr, size_needed, n);
- break;
- }
- }
-
- if (0 == hbp) return 0;
-
- /* Add it to map of valid blocks */
- if (!GC_install_counts(hbp, (word)size_needed)) return(0);
- /* This leaks memory under very rare conditions. */
-
- /* Set up header */
- if (!setup_header(hhdr, sz, kind, flags)) {
- GC_remove_counts(hbp, (word)size_needed);
- return(0); /* ditto */
- }
-
- /* Notify virtual dirty bit implementation that we are about to write. */
- /* Ensure that pointerfree objects are not protected if it's avoidable. */
- GC_remove_protection(hbp, divHBLKSZ(size_needed),
- (hhdr -> hb_descr == 0) /* pointer-free */);
-
- /* We just successfully allocated a block. Restart count of */
- /* consecutive failures. */
- {
- extern unsigned GC_fail_count;
-
- GC_fail_count = 0;
- }
-
- GC_large_free_bytes -= size_needed;
-
- GC_ASSERT(IS_MAPPED(hhdr));
- return( hbp );
-}
-
-struct hblk * GC_freehblk_ptr = 0; /* Search position hint for GC_freehblk */
-
-/*
- * Free a heap block.
- *
- * Coalesce the block with its neighbors if possible.
- *
- * All mark words are assumed to be cleared.
- */
-void
-GC_freehblk(hbp)
-struct hblk *hbp;
-{
-struct hblk *next, *prev;
-hdr *hhdr, *prevhdr, *nexthdr;
-signed_word size;
-
-
- GET_HDR(hbp, hhdr);
- size = hhdr->hb_sz;
- size = HBLKSIZE * OBJ_SZ_TO_BLOCKS(size);
- GC_remove_counts(hbp, (word)size);
- hhdr->hb_sz = size;
-
- /* Check for duplicate deallocation in the easy case */
- if (HBLK_IS_FREE(hhdr)) {
- GC_printf1("Duplicate large block deallocation of 0x%lx\n",
- (unsigned long) hbp);
- ABORT("Duplicate large block deallocation");
- }
-
- GC_ASSERT(IS_MAPPED(hhdr));
- GC_invalidate_map(hhdr);
- next = (struct hblk *)((word)hbp + size);
- GET_HDR(next, nexthdr);
- prev = GC_free_block_ending_at(hbp);
- /* Coalesce with successor, if possible */
- if(0 != nexthdr && HBLK_IS_FREE(nexthdr) && IS_MAPPED(nexthdr)) {
- GC_remove_from_fl(nexthdr, FL_UNKNOWN);
- hhdr -> hb_sz += nexthdr -> hb_sz;
- GC_remove_header(next);
- }
- /* Coalesce with predecessor, if possible. */
- if (0 != prev) {
- prevhdr = HDR(prev);
- if (IS_MAPPED(prevhdr)) {
- GC_remove_from_fl(prevhdr, FL_UNKNOWN);
- prevhdr -> hb_sz += hhdr -> hb_sz;
- GC_remove_header(hbp);
- hbp = prev;
- hhdr = prevhdr;
- }
- }
-
- GC_large_free_bytes += size;
- GC_add_to_fl(hbp, hhdr);
-}
-
projects / msp430-gcc.git / blobdiff