/* * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved. * Copyright (c) 2000 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. */ /* Boehm, February 7, 1996 4:32 pm PST */ #include #include "private/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 */ GC_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 a large block of size lw words. */ /* The block is not cleared. */ /* Flags is 0 or IGNORE_OFF_PAGE. */ /* We hold the allocation lock. */ ptr_t GC_alloc_large(lw, k, flags) word lw; int k; unsigned flags; { struct hblk * h; word n_blocks = OBJ_SZ_TO_BLOCKS(lw); ptr_t result; 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); h = GC_allochblk(lw, k, flags); # ifdef USE_MUNMAP if (0 == h) { GC_merge_unmapped(); h = GC_allochblk(lw, k, flags); } # endif while (0 == h && GC_collect_or_expand(n_blocks, (flags != 0))) { h = GC_allochblk(lw, k, flags); } if (h == 0) { result = 0; } else { int total_bytes = n_blocks * HBLKSIZE; if (n_blocks > 1) { GC_large_allocd_bytes += total_bytes; if (GC_large_allocd_bytes > GC_max_large_allocd_bytes) GC_max_large_allocd_bytes = GC_large_allocd_bytes; } result = (ptr_t) (h -> hb_body); GC_words_wasted += BYTES_TO_WORDS(total_bytes) - lw; } return result; } /* Allocate a large block of size lb bytes. Clear if appropriate. */ /* We hold the allocation lock. */ ptr_t GC_alloc_large_and_clear(lw, k, flags) word lw; int k; unsigned flags; { ptr_t result = GC_alloc_large(lw, k, flags); word n_blocks = OBJ_SZ_TO_BLOCKS(lw); if (0 == result) return 0; if (GC_debugging_started || GC_obj_kinds[k].ok_init) { /* Clear the whole block, in case of GC_realloc call. */ BZERO(result, n_blocks * HBLKSIZE); } return result; } /* allocate lb bytes for an object of kind k. */ /* 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 = MIN_WORDS; # 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.*/ /* If we only execute the second of the */ /* following assignments, we lose the free */ /* list, but that should still be OK, at least */ /* for garbage collected memory. */ *opp = obj_link(op); obj_link(op) = 0; } else { lw = ROUNDED_UP_WORDS(lb); op = (ptr_t)GC_alloc_large_and_clear(lw, k, 0); } GC_words_allocd += lw; out: return 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; { register word lw; ptr_t op; if (lb <= HBLKSIZE) return(GC_generic_malloc_inner((word)lb, k)); lw = ROUNDED_UP_WORDS(lb); op = (ptr_t)GC_alloc_large_and_clear(lw, k, IGNORE_OFF_PAGE); GC_words_allocd += lw; return op; } ptr_t GC_generic_malloc(lb, k) register word lb; register int k; { ptr_t result; DCL_LOCK_STATE; if (GC_have_errors) GC_print_all_errors(); GC_INVOKE_FINALIZERS(); if (SMALL_OBJ(lb)) { DISABLE_SIGNALS(); LOCK(); result = GC_generic_malloc_inner((word)lb, k); UNLOCK(); ENABLE_SIGNALS(); } else { word lw; word n_blocks; GC_bool init; lw = ROUNDED_UP_WORDS(lb); n_blocks = OBJ_SZ_TO_BLOCKS(lw); init = GC_obj_kinds[k].ok_init; DISABLE_SIGNALS(); LOCK(); result = (ptr_t)GC_alloc_large(lw, k, 0); if (0 != result) { if (GC_debugging_started) { BZERO(result, n_blocks * HBLKSIZE); } else { # ifdef THREADS /* Clear any memory that might be used for GC descriptors */ /* before we release the lock. */ ((word *)result)[0] = 0; ((word *)result)[1] = 0; ((word *)result)[lw-1] = 0; ((word *)result)[lw-2] = 0; # endif } } GC_words_allocd += lw; UNLOCK(); ENABLE_SIGNALS(); if (init && !GC_debugging_started && 0 != result) { BZERO(result, n_blocks * HBLKSIZE); } } if (0 == result) { return((*GC_oom_fn)(lb)); } else { return(result); } } #define GENERAL_MALLOC(lb,k) \ (GC_PTR)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__ GC_PTR GC_malloc_atomic(size_t lb) # else GC_PTR GC_malloc_atomic(lb) size_t lb; # endif { register ptr_t op; register ptr_t * opp; register word lw; DCL_LOCK_STATE; if( EXPECT(SMALL_OBJ(lb), 1) ) { # ifdef MERGE_SIZES lw = GC_size_map[lb]; # else lw = ALIGNED_WORDS(lb); # endif opp = &(GC_aobjfreelist[lw]); FASTLOCK(); if( EXPECT(!FASTLOCK_SUCCEEDED() || (op = *opp) == 0, 0) ) { FASTUNLOCK(); return(GENERAL_MALLOC((word)lb, PTRFREE)); } /* See above comment on signals. */ *opp = obj_link(op); GC_words_allocd += lw; FASTUNLOCK(); return((GC_PTR) op); } else { return(GENERAL_MALLOC((word)lb, PTRFREE)); } } /* Allocate lb bytes of composite (pointerful) data */ # ifdef __STDC__ GC_PTR GC_malloc(size_t lb) # else GC_PTR GC_malloc(lb) size_t lb; # endif { register ptr_t op; register ptr_t *opp; register word lw; DCL_LOCK_STATE; if( EXPECT(SMALL_OBJ(lb), 1) ) { # ifdef MERGE_SIZES lw = GC_size_map[lb]; # else lw = ALIGNED_WORDS(lb); # endif opp = &(GC_objfreelist[lw]); FASTLOCK(); if( EXPECT(!FASTLOCK_SUCCEEDED() || (op = *opp) == 0, 0) ) { FASTUNLOCK(); return(GENERAL_MALLOC((word)lb, NORMAL)); } /* See above comment on signals. */ GC_ASSERT(0 == obj_link(op) || (word)obj_link(op) <= (word)GC_greatest_plausible_heap_addr && (word)obj_link(op) >= (word)GC_least_plausible_heap_addr); *opp = obj_link(op); obj_link(op) = 0; GC_words_allocd += lw; FASTUNLOCK(); return((GC_PTR) op); } else { return(GENERAL_MALLOC((word)lb, NORMAL)); } } # ifdef REDIRECT_MALLOC /* Avoid unnecessary nested procedure calls here, by #defining some */ /* malloc replacements. Otherwise we end up saving a */ /* meaningless return address in the object. It also speeds things up, */ /* but it is admittedly quite ugly. */ # ifdef GC_ADD_CALLER # define RA GC_RETURN_ADDR, # else # define RA # endif # define GC_debug_malloc_replacement(lb) \ GC_debug_malloc(lb, RA "unknown", 0) # ifdef __STDC__ GC_PTR malloc(size_t lb) # else GC_PTR 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. */ # if defined(I386) && defined(GC_SOLARIS_THREADS) /* * Thread initialisation can call malloc before * we're ready for it. * It's not clear that this is enough to help matters. * The thread implementation may well call malloc at other * inopportune times. */ if (!GC_is_initialized) return sbrk(lb); # endif /* I386 && GC_SOLARIS_THREADS */ return((GC_PTR)REDIRECT_MALLOC(lb)); } # ifdef __STDC__ GC_PTR calloc(size_t n, size_t lb) # else GC_PTR calloc(n, lb) size_t n, lb; # endif { return((GC_PTR)REDIRECT_MALLOC(n*lb)); } #ifndef strdup # include # ifdef __STDC__ char *strdup(const char *s) # else char *strdup(s) char *s; # endif { size_t len = strlen(s) + 1; char * result = ((char *)REDIRECT_MALLOC(len+1)); BCOPY(s, result, len+1); return result; } #endif /* !defined(strdup) */ /* If strdup is macro defined, we assume that it actually calls malloc, */ /* and thus the right thing will happen even without overriding it. */ /* This seems to be true on most Linux systems. */ #undef GC_debug_malloc_replacement # endif /* REDIRECT_MALLOC */ /* Explicitly deallocate an object p. */ # ifdef __STDC__ void GC_free(GC_PTR p) # else void GC_free(p) GC_PTR 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); GC_ASSERT(GC_base(p) == p); # if defined(REDIRECT_MALLOC) && \ (defined(GC_SOLARIS_THREADS) || defined(GC_LINUX_THREADS) \ || defined(__MINGW32__)) /* Should this be MSWIN32 in general? */ /* For Solaris, we have to redirect malloc calls during */ /* initialization. For the others, this seems to happen */ /* implicitly. */ /* Don't try to deallocate that memory. */ if (0 == hhdr) return; # endif knd = hhdr -> hb_obj_kind; sz = hhdr -> hb_sz; ok = &GC_obj_kinds[knd]; if (EXPECT((sz <= MAXOBJSZ), 1)) { # 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 (IS_UNCOLLECTABLE(knd)) GC_non_gc_bytes -= WORDS_TO_BYTES(sz); /* Its unnecessary to clear the mark bit. If the */ /* object is reallocated, it doesn't matter. O.w. the */ /* collector will do it, since it's on a free list. */ 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 (IS_UNCOLLECTABLE(knd)) GC_non_gc_bytes -= WORDS_TO_BYTES(sz); GC_freehblk(h); UNLOCK(); ENABLE_SIGNALS(); } } /* Explicitly deallocate an object p when we already hold lock. */ /* Only used for internally allocated objects, so we can take some */ /* shortcuts. */ #ifdef THREADS void GC_free_inner(GC_PTR p) { 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; h = HBLKPTR(p); hhdr = HDR(h); knd = hhdr -> hb_obj_kind; sz = hhdr -> hb_sz; ok = &GC_obj_kinds[knd]; if (sz <= MAXOBJSZ) { GC_mem_freed += sz; if (IS_UNCOLLECTABLE(knd)) 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; } else { GC_mem_freed += sz; if (IS_UNCOLLECTABLE(knd)) GC_non_gc_bytes -= WORDS_TO_BYTES(sz); GC_freehblk(h); } } #endif /* THREADS */ # if defined(REDIRECT_MALLOC) && !defined(REDIRECT_FREE) # define REDIRECT_FREE GC_free # endif # ifdef REDIRECT_FREE # ifdef __STDC__ void free(GC_PTR p) # else void free(p) GC_PTR p; # endif { # ifndef IGNORE_FREE REDIRECT_FREE(p); # endif } # endif /* REDIRECT_MALLOC */