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- /*
- * 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 10, 1995 12:55 pm PST */
-
- #include <stdio.h>
- #include "gc_priv.h"
-
- extern ptr_t GC_clear_stack(); /* in misc.c, behaves like identity */
- void GC_extend_size_map(); /* in misc.c. */
-
- /* Allocate reclaim list for kind: */
- /* Return TRUE on success */
- bool GC_alloc_reclaim_list(kind)
- register struct obj_kind * kind;
- {
- struct hblk ** result = (struct hblk **)
- GC_scratch_alloc((MAXOBJSZ+1) * sizeof(struct hblk *));
- if (result == 0) return(FALSE);
- BZERO(result, (MAXOBJSZ+1)*sizeof(struct hblk *));
- kind -> ok_reclaim_list = result;
- return(TRUE);
- }
-
- /* allocate lb bytes for an object of kind. */
- /* Should not be used to directly to allocate */
- /* objects such as STUBBORN objects that */
- /* require special handling on allocation. */
- /* First a version that assumes we already */
- /* hold lock: */
- ptr_t GC_generic_malloc_inner(lb, k)
- register word lb;
- register int k;
- {
- register word lw;
- register ptr_t op;
- register ptr_t *opp;
-
- if( SMALL_OBJ(lb) ) {
- register struct obj_kind * kind = GC_obj_kinds + k;
- # ifdef MERGE_SIZES
- lw = GC_size_map[lb];
- # else
- lw = ALIGNED_WORDS(lb);
- if (lw == 0) lw = 1;
- # endif
- opp = &(kind -> ok_freelist[lw]);
- if( (op = *opp) == 0 ) {
- # ifdef MERGE_SIZES
- if (GC_size_map[lb] == 0) {
- if (!GC_is_initialized) GC_init_inner();
- if (GC_size_map[lb] == 0) GC_extend_size_map(lb);
- return(GC_generic_malloc_inner(lb, k));
- }
- # else
- if (!GC_is_initialized) {
- GC_init_inner();
- return(GC_generic_malloc_inner(lb, k));
- }
- # endif
- if (kind -> ok_reclaim_list == 0) {
- if (!GC_alloc_reclaim_list(kind)) goto out;
- }
- op = GC_allocobj(lw, k);
- if (op == 0) goto out;
- }
- /* Here everything is in a consistent state. */
- /* We assume the following assignment is */
- /* atomic. If we get aborted */
- /* after the assignment, we lose an object, */
- /* but that's benign. */
- /* Volatile declarations may need to be added */
- /* to prevent the compiler from breaking things.*/
- *opp = obj_link(op);
- obj_link(op) = 0;
- } else {
- register struct hblk * h;
- register word n_blocks = divHBLKSZ(ADD_SLOP(lb)
- + HDR_BYTES + HBLKSIZE-1);
-
- if (!GC_is_initialized) GC_init_inner();
- /* Do our share of marking work */
- if(GC_incremental && !GC_dont_gc)
- GC_collect_a_little_inner((int)n_blocks);
- lw = ROUNDED_UP_WORDS(lb);
- while ((h = GC_allochblk(lw, k, 0)) == 0
- && GC_collect_or_expand(n_blocks));
- if (h == 0) {
- op = 0;
- } else {
- op = (ptr_t) (h -> hb_body);
- GC_words_wasted += BYTES_TO_WORDS(n_blocks * HBLKSIZE) - lw;
- }
- }
- GC_words_allocd += lw;
-
- out:
- return((ptr_t)op);
- }
-
- /* Allocate a composite object of size n bytes. The caller guarantees */
- /* that pointers past the first page are not relevant. Caller holds */
- /* allocation lock. */
- ptr_t GC_generic_malloc_inner_ignore_off_page(lb, k)
- register size_t lb;
- register int k;
- {
- # ifdef ALL_INTERIOR_POINTERS
- register struct hblk * h;
- register word n_blocks;
- register word lw;
- register ptr_t op;
-
- if (lb <= HBLKSIZE)
- return(GC_generic_malloc_inner((word)lb, k));
- n_blocks = divHBLKSZ(ADD_SLOP(lb) + HDR_BYTES + HBLKSIZE-1);
- if (!GC_is_initialized) GC_init_inner();
- /* Do our share of marking work */
- if(GC_incremental && !GC_dont_gc)
- GC_collect_a_little_inner((int)n_blocks);
- lw = ROUNDED_UP_WORDS(lb);
- while ((h = GC_allochblk(lw, k, IGNORE_OFF_PAGE)) == 0
- && GC_collect_or_expand(n_blocks));
- if (h == 0) {
- op = 0;
- } else {
- op = (ptr_t) (h -> hb_body);
- GC_words_wasted += BYTES_TO_WORDS(n_blocks * HBLKSIZE) - lw;
- }
- GC_words_allocd += lw;
- return((ptr_t)op);
- # else
- return(GC_generic_malloc_inner((word)lb, k));
- # endif
- }
-
- ptr_t GC_generic_malloc_ignore_off_page(lb, k)
- register size_t lb;
- register int k;
- {
- register ptr_t result;
- DCL_LOCK_STATE;
-
- GC_invoke_finalizers();
- DISABLE_SIGNALS();
- LOCK();
- result = GC_generic_malloc_inner_ignore_off_page(lb,k);
- UNLOCK();
- ENABLE_SIGNALS();
- return(result);
- }
-
- # if defined(__STDC__) || defined(__cplusplus)
- void * GC_malloc_ignore_off_page(size_t lb)
- # else
- char * GC_malloc_ignore_off_page(lb)
- register size_t lb;
- # endif
- {
- return((extern_ptr_t)GC_generic_malloc_ignore_off_page(lb, NORMAL));
- }
-
- # if defined(__STDC__) || defined(__cplusplus)
- void * GC_malloc_atomic_ignore_off_page(size_t lb)
- # else
- char * GC_malloc_atomic_ignore_off_page(lb)
- register size_t lb;
- # endif
- {
- return((extern_ptr_t)GC_generic_malloc_ignore_off_page(lb, PTRFREE));
- }
-
- ptr_t GC_generic_malloc(lb, k)
- register word lb;
- register int k;
- {
- ptr_t result;
- DCL_LOCK_STATE;
-
- GC_invoke_finalizers();
- DISABLE_SIGNALS();
- LOCK();
- result = GC_generic_malloc_inner(lb, k);
- UNLOCK();
- ENABLE_SIGNALS();
- return(result);
- }
-
-
- /* Analogous to the above, but assumes a small object size, and */
- /* bypasses MERGE_SIZES mechanism. Used by gc_inline.h. */
- ptr_t GC_generic_malloc_words_small(lw, k)
- register word lw;
- register int k;
- {
- register ptr_t op;
- register ptr_t *opp;
- register struct obj_kind * kind = GC_obj_kinds + k;
- DCL_LOCK_STATE;
-
- GC_invoke_finalizers();
- DISABLE_SIGNALS();
- LOCK();
- opp = &(kind -> ok_freelist[lw]);
- if( (op = *opp) == 0 ) {
- if (!GC_is_initialized) {
- GC_init_inner();
- }
- if (kind -> ok_reclaim_list == 0) {
- if (!GC_alloc_reclaim_list(kind)) goto out;
- }
- op = GC_clear_stack(GC_allocobj(lw, k));
- if (op == 0) goto out;
- }
- *opp = obj_link(op);
- obj_link(op) = 0;
- GC_words_allocd += lw;
-
- out:
- UNLOCK();
- ENABLE_SIGNALS();
- return((ptr_t)op);
- }
-
- #if defined(THREADS) && !defined(SRC_M3)
- /* Return a list of 1 or more objects of the indicated size, linked */
- /* through the first word in the object. This has the advantage that */
- /* it acquires the allocation lock only once, and may greatly reduce */
- /* time wasted contending for the allocation lock. Typical usage would */
- /* be in a thread that requires many items of the same size. It would */
- /* keep its own free list in thread-local storage, and call */
- /* GC_malloc_many or friends to replenish it. (We do not round up */
- /* object sizes, since a call indicates the intention to consume many */
- /* objects of exactly this size.) */
- /* Note that the client should usually clear the link field. */
- ptr_t GC_generic_malloc_many(lb, k)
- register word lb;
- register int k;
- {
- ptr_t op;
- register ptr_t p;
- ptr_t *opp;
- word lw;
- register word my_words_allocd;
- DCL_LOCK_STATE;
-
- if (!SMALL_OBJ(lb)) {
- op = GC_generic_malloc(lb, k);
- obj_link(op) = 0;
- return(op);
- }
- lw = ALIGNED_WORDS(lb);
- GC_invoke_finalizers();
- DISABLE_SIGNALS();
- LOCK();
- opp = &(GC_obj_kinds[k].ok_freelist[lw]);
- if( (op = *opp) == 0 ) {
- if (!GC_is_initialized) {
- GC_init_inner();
- }
- op = GC_clear_stack(GC_allocobj(lw, k));
- if (op == 0) goto out;
- }
- *opp = 0;
- my_words_allocd = 0;
- for (p = op; p != 0; p = obj_link(p)) {
- my_words_allocd += lw;
- if (my_words_allocd >= BODY_SZ) {
- *opp = obj_link(p);
- obj_link(p) = 0;
- break;
- }
- }
- GC_words_allocd += my_words_allocd;
-
- out:
- UNLOCK();
- ENABLE_SIGNALS();
- return(op);
-
- }
-
- void * GC_malloc_many(size_t lb)
- {
- return(GC_generic_malloc_many(lb, NORMAL));
- }
-
- /* Note that the "atomic" version of this would be unsafe, since the */
- /* links would not be seen by the collector. */
- # endif
-
- #define GENERAL_MALLOC(lb,k) \
- (extern_ptr_t)GC_clear_stack(GC_generic_malloc((word)lb, k))
- /* We make the GC_clear_stack_call a tail call, hoping to get more of */
- /* the stack. */
-
- /* Allocate lb bytes of atomic (pointerfree) data */
- # ifdef __STDC__
- extern_ptr_t GC_malloc_atomic(size_t lb)
- # else
- extern_ptr_t GC_malloc_atomic(lb)
- size_t lb;
- # endif
- {
- register ptr_t op;
- register ptr_t * opp;
- register word lw;
- DCL_LOCK_STATE;
-
- if( SMALL_OBJ(lb) ) {
- # ifdef MERGE_SIZES
- lw = GC_size_map[lb];
- # else
- lw = ALIGNED_WORDS(lb);
- # endif
- opp = &(GC_aobjfreelist[lw]);
- FASTLOCK();
- if( !FASTLOCK_SUCCEEDED() || (op = *opp) == 0 ) {
- FASTUNLOCK();
- return(GENERAL_MALLOC((word)lb, PTRFREE));
- }
- /* See above comment on signals. */
- *opp = obj_link(op);
- GC_words_allocd += lw;
- FASTUNLOCK();
- return((extern_ptr_t) op);
- } else {
- return(GENERAL_MALLOC((word)lb, PTRFREE));
- }
- }
-
- /* Allocate lb bytes of composite (pointerful) data */
- # ifdef __STDC__
- extern_ptr_t GC_malloc(size_t lb)
- # else
- extern_ptr_t GC_malloc(lb)
- size_t lb;
- # endif
- {
- register ptr_t op;
- register ptr_t *opp;
- register word lw;
- DCL_LOCK_STATE;
-
- if( SMALL_OBJ(lb) ) {
- # ifdef MERGE_SIZES
- lw = GC_size_map[lb];
- # else
- lw = ALIGNED_WORDS(lb);
- # endif
- opp = &(GC_objfreelist[lw]);
- FASTLOCK();
- if( !FASTLOCK_SUCCEEDED() || (op = *opp) == 0 ) {
- FASTUNLOCK();
- return(GENERAL_MALLOC((word)lb, NORMAL));
- }
- /* See above comment on signals. */
- *opp = obj_link(op);
- obj_link(op) = 0;
- GC_words_allocd += lw;
- FASTUNLOCK();
- return((extern_ptr_t) op);
- } else {
- return(GENERAL_MALLOC((word)lb, NORMAL));
- }
- }
-
- # ifdef REDIRECT_MALLOC
- # ifdef __STDC__
- extern_ptr_t malloc(size_t lb)
- # else
- extern_ptr_t malloc(lb)
- size_t lb;
- # endif
- {
- /* It might help to manually inline the GC_malloc call here. */
- /* But any decent compiler should reduce the extra procedure call */
- /* to at most a jump instruction in this case. */
- return(REDIRECT_MALLOC(lb));
- }
-
- # ifdef __STDC__
- extern_ptr_t calloc(size_t n, size_t lb)
- # else
- extern_ptr_t calloc(n, lb)
- size_t n, lb;
- # endif
- {
- return(REDIRECT_MALLOC(n*lb));
- }
- # endif /* REDIRECT_MALLOC */
-
- /* Allocate lb bytes of pointerful, traced, but not collectable data */
- # ifdef __STDC__
- extern_ptr_t GC_malloc_uncollectable(size_t lb)
- # else
- extern_ptr_t GC_malloc_uncollectable(lb)
- size_t lb;
- # endif
- {
- register ptr_t op;
- register ptr_t *opp;
- register word lw;
- DCL_LOCK_STATE;
-
- if( SMALL_OBJ(lb) ) {
- # ifdef MERGE_SIZES
- # ifdef ADD_BYTE_AT_END
- lb--; /* We don't need the extra byte, since this won't be */
- /* collected anyway. */
- # endif
- lw = GC_size_map[lb];
- # else
- lw = ALIGNED_WORDS(lb);
- # endif
- opp = &(GC_uobjfreelist[lw]);
- FASTLOCK();
- if( FASTLOCK_SUCCEEDED() && (op = *opp) != 0 ) {
- /* See above comment on signals. */
- *opp = obj_link(op);
- obj_link(op) = 0;
- GC_words_allocd += lw;
- GC_set_mark_bit(op);
- GC_non_gc_bytes += WORDS_TO_BYTES(lw);
- FASTUNLOCK();
- return((extern_ptr_t) op);
- }
- FASTUNLOCK();
- op = (ptr_t)GC_generic_malloc((word)lb, UNCOLLECTABLE);
- } else {
- op = (ptr_t)GC_generic_malloc((word)lb, UNCOLLECTABLE);
- }
- /* We don't need the lock here, since we have an undisguised */
- /* pointer. We do need to hold the lock while we adjust */
- /* mark bits. */
- {
- register struct hblk * h;
-
- h = HBLKPTR(op);
- lw = HDR(h) -> hb_sz;
-
- DISABLE_SIGNALS();
- LOCK();
- GC_set_mark_bit(op);
- GC_non_gc_bytes += WORDS_TO_BYTES(lw);
- UNLOCK();
- ENABLE_SIGNALS();
- return((extern_ptr_t) op);
- }
- }
-
- extern_ptr_t GC_generic_or_special_malloc(lb,knd)
- word lb;
- int knd;
- {
- switch(knd) {
- # ifdef STUBBORN_ALLOC
- case STUBBORN:
- return(GC_malloc_stubborn((size_t)lb));
- # endif
- case PTRFREE:
- return(GC_malloc_atomic((size_t)lb));
- case NORMAL:
- return(GC_malloc((size_t)lb));
- case UNCOLLECTABLE:
- return(GC_malloc_uncollectable((size_t)lb));
- default:
- return(GC_generic_malloc(lb,knd));
- }
- }
-
-
- /* Change the size of the block pointed to by p to contain at least */
- /* lb bytes. The object may be (and quite likely will be) moved. */
- /* The kind (e.g. atomic) is the same as that of the old. */
- /* Shrinking of large blocks is not implemented well. */
- # ifdef __STDC__
- extern_ptr_t GC_realloc(extern_ptr_t p, size_t lb)
- # else
- extern_ptr_t GC_realloc(p,lb)
- extern_ptr_t p;
- size_t lb;
- # endif
- {
- register struct hblk * h;
- register hdr * hhdr;
- register word sz; /* Current size in bytes */
- register word orig_sz; /* Original sz in bytes */
- int obj_kind;
-
- if (p == 0) return(GC_malloc(lb)); /* Required by ANSI */
- h = HBLKPTR(p);
- hhdr = HDR(h);
- sz = hhdr -> hb_sz;
- obj_kind = hhdr -> hb_obj_kind;
- sz = WORDS_TO_BYTES(sz);
- orig_sz = sz;
-
- if (sz > WORDS_TO_BYTES(MAXOBJSZ)) {
- /* Round it up to the next whole heap block */
-
- sz = (sz+HDR_BYTES+HBLKSIZE-1)
- & (~HBLKMASK);
- sz -= HDR_BYTES;
- hhdr -> hb_sz = BYTES_TO_WORDS(sz);
- if (obj_kind == UNCOLLECTABLE) GC_non_gc_bytes += (sz - orig_sz);
- /* Extra area is already cleared by allochblk. */
- }
- if (ADD_SLOP(lb) <= sz) {
- if (lb >= (sz >> 1)) {
- # ifdef STUBBORN_ALLOC
- if (obj_kind == STUBBORN) GC_change_stubborn(p);
- # endif
- if (orig_sz > lb) {
- /* Clear unneeded part of object to avoid bogus pointer */
- /* tracing. */
- /* Safe for stubborn objects. */
- BZERO(((ptr_t)p) + lb, orig_sz - lb);
- }
- return(p);
- } else {
- /* shrink */
- extern_ptr_t result =
- GC_generic_or_special_malloc((word)lb, obj_kind);
-
- if (result == 0) return(0);
- /* Could also return original object. But this */
- /* gives the client warning of imminent disaster. */
- BCOPY(p, result, lb);
- GC_free(p);
- return(result);
- }
- } else {
- /* grow */
- extern_ptr_t result =
- GC_generic_or_special_malloc((word)lb, obj_kind);
-
- if (result == 0) return(0);
- BCOPY(p, result, sz);
- GC_free(p);
- return(result);
- }
- }
-
- # ifdef REDIRECT_MALLOC
- # ifdef __STDC__
- extern_ptr_t realloc(extern_ptr_t p, size_t lb)
- # else
- extern_ptr_t realloc(p,lb)
- extern_ptr_t p;
- size_t lb;
- # endif
- {
- return(GC_realloc(p, lb));
- }
- # endif /* REDIRECT_MALLOC */
-
- /* Explicitly deallocate an object p. */
- # ifdef __STDC__
- void GC_free(extern_ptr_t p)
- # else
- void GC_free(p)
- extern_ptr_t p;
- # endif
- {
- register struct hblk *h;
- register hdr *hhdr;
- register signed_word sz;
- register ptr_t * flh;
- register int knd;
- register struct obj_kind * ok;
- DCL_LOCK_STATE;
-
- if (p == 0) return;
- /* Required by ANSI. It's not my fault ... */
- h = HBLKPTR(p);
- hhdr = HDR(h);
- knd = hhdr -> hb_obj_kind;
- sz = hhdr -> hb_sz;
- ok = &GC_obj_kinds[knd];
- if (sz <= MAXOBJSZ) {
- # ifdef THREADS
- DISABLE_SIGNALS();
- LOCK();
- # endif
- GC_mem_freed += sz;
- /* A signal here can make GC_mem_freed and GC_non_gc_bytes */
- /* inconsistent. We claim this is benign. */
- if (knd == UNCOLLECTABLE) GC_non_gc_bytes -= WORDS_TO_BYTES(sz);
- if (ok -> ok_init) {
- BZERO((word *)p + 1, WORDS_TO_BYTES(sz-1));
- }
- flh = &(ok -> ok_freelist[sz]);
- obj_link(p) = *flh;
- *flh = (ptr_t)p;
- # ifdef THREADS
- UNLOCK();
- ENABLE_SIGNALS();
- # endif
- } else {
- DISABLE_SIGNALS();
- LOCK();
- GC_mem_freed += sz;
- if (knd == UNCOLLECTABLE) GC_non_gc_bytes -= WORDS_TO_BYTES(sz);
- GC_freehblk(h);
- UNLOCK();
- ENABLE_SIGNALS();
- }
- }
-
- # ifdef REDIRECT_MALLOC
- # ifdef __STDC__
- void free(extern_ptr_t p)
- # else
- void free(p)
- extern_ptr_t p;
- # endif
- {
- GC_free(p);
- }
- # endif /* REDIRECT_MALLOC */
-