X-Git-Url: http://wien.tomnetworks.com/gitweb/?p=hs-boehmgc.git;a=blobdiff_plain;f=gc-7.2%2Ftypd_mlc.c;fp=gc-7.2%2Ftypd_mlc.c;h=32a9b0f3eec639f60b909517f1701df32b94df57;hp=0000000000000000000000000000000000000000;hb=324587ba93dc77f37406d41fd2a20d0e0d94fb1d;hpb=2a4ea609491b225a1ceb06da70396e93916f137a diff --git a/gc-7.2/typd_mlc.c b/gc-7.2/typd_mlc.c new file mode 100644 index 0000000..32a9b0f --- /dev/null +++ b/gc-7.2/typd_mlc.c @@ -0,0 +1,726 @@ +/* + * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved. + * opyright (c) 1999-2000 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. + * + */ + +#include "private/gc_pmark.h" + +/* + * Some simple primitives for allocation with explicit type information. + * Simple objects are allocated such that they contain a GC_descr at the + * end (in the last allocated word). This descriptor may be a procedure + * which then examines an extended descriptor passed as its environment. + * + * Arrays are treated as simple objects if they have sufficiently simple + * structure. Otherwise they are allocated from an array kind that supplies + * a special mark procedure. These arrays contain a pointer to a + * complex_descriptor as their last word. + * This is done because the environment field is too small, and the collector + * must trace the complex_descriptor. + * + * Note that descriptors inside objects may appear cleared, if we encounter a + * false reference to an object on a free list. In the GC_descr case, this + * is OK, since a 0 descriptor corresponds to examining no fields. + * In the complex_descriptor case, we explicitly check for that case. + * + * MAJOR PARTS OF THIS CODE HAVE NOT BEEN TESTED AT ALL and are not testable, + * since they are not accessible through the current interface. + */ + +#include "gc_typed.h" + +#define TYPD_EXTRA_BYTES (sizeof(word) - EXTRA_BYTES) + +STATIC GC_bool GC_explicit_typing_initialized = FALSE; + +STATIC int GC_explicit_kind = 0; + /* Object kind for objects with indirect */ + /* (possibly extended) descriptors. */ + +STATIC int GC_array_kind = 0; + /* Object kind for objects with complex */ + /* descriptors and GC_array_mark_proc. */ + +/* Extended descriptors. GC_typed_mark_proc understands these. */ +/* These are used for simple objects that are larger than what */ +/* can be described by a BITMAP_BITS sized bitmap. */ +typedef struct { + word ed_bitmap; /* lsb corresponds to first word. */ + GC_bool ed_continued; /* next entry is continuation. */ +} ext_descr; + +/* Array descriptors. GC_array_mark_proc understands these. */ +/* We may eventually need to add provisions for headers and */ +/* trailers. Hence we provide for tree structured descriptors, */ +/* though we don't really use them currently. */ +typedef union ComplexDescriptor { + struct LeafDescriptor { /* Describes simple array */ + word ld_tag; +# define LEAF_TAG 1 + size_t ld_size; /* bytes per element */ + /* multiple of ALIGNMENT */ + size_t ld_nelements; /* Number of elements. */ + GC_descr ld_descriptor; /* A simple length, bitmap, */ + /* or procedure descriptor. */ + } ld; + struct ComplexArrayDescriptor { + word ad_tag; +# define ARRAY_TAG 2 + size_t ad_nelements; + union ComplexDescriptor * ad_element_descr; + } ad; + struct SequenceDescriptor { + word sd_tag; +# define SEQUENCE_TAG 3 + union ComplexDescriptor * sd_first; + union ComplexDescriptor * sd_second; + } sd; +} complex_descriptor; +#define TAG ld.ld_tag + +STATIC ext_descr * GC_ext_descriptors = NULL; + /* Points to array of extended */ + /* descriptors. */ + +STATIC size_t GC_ed_size = 0; /* Current size of above arrays. */ +#define ED_INITIAL_SIZE 100 + +STATIC size_t GC_avail_descr = 0; /* Next available slot. */ + +STATIC int GC_typed_mark_proc_index = 0; /* Indices of my mark */ +STATIC int GC_array_mark_proc_index = 0; /* procedures. */ + +STATIC void GC_push_typed_structures_proc(void) +{ + GC_push_all((ptr_t)&GC_ext_descriptors, + (ptr_t)&GC_ext_descriptors + sizeof(word)); +} + +/* Add a multiword bitmap to GC_ext_descriptors arrays. Return */ +/* starting index. */ +/* Returns -1 on failure. */ +/* Caller does not hold allocation lock. */ +STATIC signed_word GC_add_ext_descriptor(GC_bitmap bm, word nbits) +{ + size_t nwords = divWORDSZ(nbits + WORDSZ-1); + signed_word result; + size_t i; + word last_part; + size_t extra_bits; + DCL_LOCK_STATE; + + LOCK(); + while (GC_avail_descr + nwords >= GC_ed_size) { + ext_descr * new; + size_t new_size; + word ed_size = GC_ed_size; + + if (ed_size == 0) { + GC_push_typed_structures = GC_push_typed_structures_proc; + UNLOCK(); + new_size = ED_INITIAL_SIZE; + } else { + UNLOCK(); + new_size = 2 * ed_size; + if (new_size > MAX_ENV) return(-1); + } + new = (ext_descr *) GC_malloc_atomic(new_size * sizeof(ext_descr)); + if (new == 0) return(-1); + LOCK(); + if (ed_size == GC_ed_size) { + if (GC_avail_descr != 0) { + BCOPY(GC_ext_descriptors, new, + GC_avail_descr * sizeof(ext_descr)); + } + GC_ed_size = new_size; + GC_ext_descriptors = new; + } /* else another thread already resized it in the meantime */ + } + result = GC_avail_descr; + for (i = 0; i < nwords-1; i++) { + GC_ext_descriptors[result + i].ed_bitmap = bm[i]; + GC_ext_descriptors[result + i].ed_continued = TRUE; + } + last_part = bm[i]; + /* Clear irrelevant bits. */ + extra_bits = nwords * WORDSZ - nbits; + last_part <<= extra_bits; + last_part >>= extra_bits; + GC_ext_descriptors[result + i].ed_bitmap = last_part; + GC_ext_descriptors[result + i].ed_continued = FALSE; + GC_avail_descr += nwords; + UNLOCK(); + return(result); +} + +/* Table of bitmap descriptors for n word long all pointer objects. */ +STATIC GC_descr GC_bm_table[WORDSZ/2]; + +/* Return a descriptor for the concatenation of 2 nwords long objects, */ +/* each of which is described by descriptor. */ +/* The result is known to be short enough to fit into a bitmap */ +/* descriptor. */ +/* Descriptor is a GC_DS_LENGTH or GC_DS_BITMAP descriptor. */ +STATIC GC_descr GC_double_descr(GC_descr descriptor, word nwords) +{ + if ((descriptor & GC_DS_TAGS) == GC_DS_LENGTH) { + descriptor = GC_bm_table[BYTES_TO_WORDS((word)descriptor)]; + }; + descriptor |= (descriptor & ~GC_DS_TAGS) >> nwords; + return(descriptor); +} + +STATIC complex_descriptor * +GC_make_sequence_descriptor(complex_descriptor *first, + complex_descriptor *second); + +/* Build a descriptor for an array with nelements elements, */ +/* each of which can be described by a simple descriptor. */ +/* We try to optimize some common cases. */ +/* If the result is COMPLEX, then a complex_descr* is returned */ +/* in *complex_d. */ +/* If the result is LEAF, then we built a LeafDescriptor in */ +/* the structure pointed to by leaf. */ +/* The tag in the leaf structure is not set. */ +/* If the result is SIMPLE, then a GC_descr */ +/* is returned in *simple_d. */ +/* If the result is NO_MEM, then */ +/* we failed to allocate the descriptor. */ +/* The implementation knows that GC_DS_LENGTH is 0. */ +/* *leaf, *complex_d, and *simple_d may be used as temporaries */ +/* during the construction. */ +#define COMPLEX 2 +#define LEAF 1 +#define SIMPLE 0 +#define NO_MEM (-1) +STATIC int GC_make_array_descriptor(size_t nelements, size_t size, + GC_descr descriptor, GC_descr *simple_d, + complex_descriptor **complex_d, + struct LeafDescriptor * leaf) +{ +# define OPT_THRESHOLD 50 + /* For larger arrays, we try to combine descriptors of adjacent */ + /* descriptors to speed up marking, and to reduce the amount */ + /* of space needed on the mark stack. */ + if ((descriptor & GC_DS_TAGS) == GC_DS_LENGTH) { + if (descriptor == (GC_descr)size) { + *simple_d = nelements * descriptor; + return(SIMPLE); + } else if ((word)descriptor == 0) { + *simple_d = (GC_descr)0; + return(SIMPLE); + } + } + if (nelements <= OPT_THRESHOLD) { + if (nelements <= 1) { + if (nelements == 1) { + *simple_d = descriptor; + return(SIMPLE); + } else { + *simple_d = (GC_descr)0; + return(SIMPLE); + } + } + } else if (size <= BITMAP_BITS/2 + && (descriptor & GC_DS_TAGS) != GC_DS_PROC + && (size & (sizeof(word)-1)) == 0) { + int result = + GC_make_array_descriptor(nelements/2, 2*size, + GC_double_descr(descriptor, + BYTES_TO_WORDS(size)), + simple_d, complex_d, leaf); + if ((nelements & 1) == 0) { + return(result); + } else { + struct LeafDescriptor * one_element = + (struct LeafDescriptor *) + GC_malloc_atomic(sizeof(struct LeafDescriptor)); + + if (result == NO_MEM || one_element == 0) return(NO_MEM); + one_element -> ld_tag = LEAF_TAG; + one_element -> ld_size = size; + one_element -> ld_nelements = 1; + one_element -> ld_descriptor = descriptor; + switch(result) { + case SIMPLE: + { + struct LeafDescriptor * beginning = + (struct LeafDescriptor *) + GC_malloc_atomic(sizeof(struct LeafDescriptor)); + if (beginning == 0) return(NO_MEM); + beginning -> ld_tag = LEAF_TAG; + beginning -> ld_size = size; + beginning -> ld_nelements = 1; + beginning -> ld_descriptor = *simple_d; + *complex_d = GC_make_sequence_descriptor( + (complex_descriptor *)beginning, + (complex_descriptor *)one_element); + break; + } + case LEAF: + { + struct LeafDescriptor * beginning = + (struct LeafDescriptor *) + GC_malloc_atomic(sizeof(struct LeafDescriptor)); + if (beginning == 0) return(NO_MEM); + beginning -> ld_tag = LEAF_TAG; + beginning -> ld_size = leaf -> ld_size; + beginning -> ld_nelements = leaf -> ld_nelements; + beginning -> ld_descriptor = leaf -> ld_descriptor; + *complex_d = GC_make_sequence_descriptor( + (complex_descriptor *)beginning, + (complex_descriptor *)one_element); + break; + } + case COMPLEX: + *complex_d = GC_make_sequence_descriptor( + *complex_d, + (complex_descriptor *)one_element); + break; + } + return(COMPLEX); + } + } + + leaf -> ld_size = size; + leaf -> ld_nelements = nelements; + leaf -> ld_descriptor = descriptor; + return(LEAF); +} + +STATIC complex_descriptor * +GC_make_sequence_descriptor(complex_descriptor *first, + complex_descriptor *second) +{ + struct SequenceDescriptor * result = + (struct SequenceDescriptor *) + GC_malloc(sizeof(struct SequenceDescriptor)); + /* Can't result in overly conservative marking, since tags are */ + /* very small integers. Probably faster than maintaining type */ + /* info. */ + if (result != 0) { + result -> sd_tag = SEQUENCE_TAG; + result -> sd_first = first; + result -> sd_second = second; + } + return((complex_descriptor *)result); +} + +#ifdef UNDEFINED + complex_descriptor * GC_make_complex_array_descriptor(word nelements, + complex_descriptor *descr) + { + struct ComplexArrayDescriptor * result = + (struct ComplexArrayDescriptor *) + GC_malloc(sizeof(struct ComplexArrayDescriptor)); + + if (result != 0) { + result -> ad_tag = ARRAY_TAG; + result -> ad_nelements = nelements; + result -> ad_element_descr = descr; + } + return((complex_descriptor *)result); + } +#endif + +STATIC ptr_t * GC_eobjfreelist = NULL; + +STATIC ptr_t * GC_arobjfreelist = NULL; + +STATIC mse * GC_typed_mark_proc(word * addr, mse * mark_stack_ptr, + mse * mark_stack_limit, word env); + +STATIC mse * GC_array_mark_proc(word * addr, mse * mark_stack_ptr, + mse * mark_stack_limit, word env); + +/* Caller does not hold allocation lock. */ +STATIC void GC_init_explicit_typing(void) +{ + register unsigned i; + DCL_LOCK_STATE; + + GC_STATIC_ASSERT(sizeof(struct LeafDescriptor) % sizeof(word) == 0); + LOCK(); + if (GC_explicit_typing_initialized) { + UNLOCK(); + return; + } + GC_explicit_typing_initialized = TRUE; + /* Set up object kind with simple indirect descriptor. */ + GC_eobjfreelist = (ptr_t *)GC_new_free_list_inner(); + GC_explicit_kind = GC_new_kind_inner( + (void **)GC_eobjfreelist, + (((word)WORDS_TO_BYTES(-1)) | GC_DS_PER_OBJECT), + TRUE, TRUE); + /* Descriptors are in the last word of the object. */ + GC_typed_mark_proc_index = GC_new_proc_inner(GC_typed_mark_proc); + /* Set up object kind with array descriptor. */ + GC_arobjfreelist = (ptr_t *)GC_new_free_list_inner(); + GC_array_mark_proc_index = GC_new_proc_inner(GC_array_mark_proc); + GC_array_kind = GC_new_kind_inner( + (void **)GC_arobjfreelist, + GC_MAKE_PROC(GC_array_mark_proc_index, 0), + FALSE, TRUE); + for (i = 0; i < WORDSZ/2; i++) { + GC_descr d = (((word)(-1)) >> (WORDSZ - i)) << (WORDSZ - i); + d |= GC_DS_BITMAP; + GC_bm_table[i] = d; + } + UNLOCK(); +} + +STATIC mse * GC_typed_mark_proc(word * addr, mse * mark_stack_ptr, + mse * mark_stack_limit, word env) +{ + word bm = GC_ext_descriptors[env].ed_bitmap; + word * current_p = addr; + word current; + ptr_t greatest_ha = GC_greatest_plausible_heap_addr; + ptr_t least_ha = GC_least_plausible_heap_addr; + DECLARE_HDR_CACHE; + + INIT_HDR_CACHE; + for (; bm != 0; bm >>= 1, current_p++) { + if (bm & 1) { + current = *current_p; + FIXUP_POINTER(current); + if ((ptr_t)current >= least_ha && (ptr_t)current <= greatest_ha) { + PUSH_CONTENTS((ptr_t)current, mark_stack_ptr, + mark_stack_limit, (ptr_t)current_p, exit1); + } + } + } + if (GC_ext_descriptors[env].ed_continued) { + /* Push an entry with the rest of the descriptor back onto the */ + /* stack. Thus we never do too much work at once. Note that */ + /* we also can't overflow the mark stack unless we actually */ + /* mark something. */ + mark_stack_ptr++; + if (mark_stack_ptr >= mark_stack_limit) { + mark_stack_ptr = GC_signal_mark_stack_overflow(mark_stack_ptr); + } + mark_stack_ptr -> mse_start = (ptr_t)(addr + WORDSZ); + mark_stack_ptr -> mse_descr = + GC_MAKE_PROC(GC_typed_mark_proc_index, env+1); + } + return(mark_stack_ptr); +} + +/* Return the size of the object described by d. It would be faster to */ +/* store this directly, or to compute it as part of */ +/* GC_push_complex_descriptor, but hopefully it doesn't matter. */ +STATIC word GC_descr_obj_size(complex_descriptor *d) +{ + switch(d -> TAG) { + case LEAF_TAG: + return(d -> ld.ld_nelements * d -> ld.ld_size); + case ARRAY_TAG: + return(d -> ad.ad_nelements + * GC_descr_obj_size(d -> ad.ad_element_descr)); + case SEQUENCE_TAG: + return(GC_descr_obj_size(d -> sd.sd_first) + + GC_descr_obj_size(d -> sd.sd_second)); + default: + ABORT("Bad complex descriptor"); + /*NOTREACHED*/ return 0; /*NOTREACHED*/ + } +} + +/* Push descriptors for the object at addr with complex descriptor d */ +/* onto the mark stack. Return 0 if the mark stack overflowed. */ +STATIC mse * GC_push_complex_descriptor(word *addr, complex_descriptor *d, + mse *msp, mse *msl) +{ + register ptr_t current = (ptr_t) addr; + register word nelements; + register word sz; + register word i; + + switch(d -> TAG) { + case LEAF_TAG: + { + register GC_descr descr = d -> ld.ld_descriptor; + + nelements = d -> ld.ld_nelements; + if (msl - msp <= (ptrdiff_t)nelements) return(0); + sz = d -> ld.ld_size; + for (i = 0; i < nelements; i++) { + msp++; + msp -> mse_start = current; + msp -> mse_descr = descr; + current += sz; + } + return(msp); + } + case ARRAY_TAG: + { + register complex_descriptor *descr = d -> ad.ad_element_descr; + + nelements = d -> ad.ad_nelements; + sz = GC_descr_obj_size(descr); + for (i = 0; i < nelements; i++) { + msp = GC_push_complex_descriptor((word *)current, descr, + msp, msl); + if (msp == 0) return(0); + current += sz; + } + return(msp); + } + case SEQUENCE_TAG: + { + sz = GC_descr_obj_size(d -> sd.sd_first); + msp = GC_push_complex_descriptor((word *)current, d -> sd.sd_first, + msp, msl); + if (msp == 0) return(0); + current += sz; + msp = GC_push_complex_descriptor((word *)current, d -> sd.sd_second, + msp, msl); + return(msp); + } + default: + ABORT("Bad complex descriptor"); + /*NOTREACHED*/ return 0; /*NOTREACHED*/ + } +} + +/*ARGSUSED*/ +STATIC mse * GC_array_mark_proc(word * addr, mse * mark_stack_ptr, + mse * mark_stack_limit, word env) +{ + hdr * hhdr = HDR(addr); + size_t sz = hhdr -> hb_sz; + size_t nwords = BYTES_TO_WORDS(sz); + complex_descriptor * descr = (complex_descriptor *)(addr[nwords-1]); + mse * orig_mark_stack_ptr = mark_stack_ptr; + mse * new_mark_stack_ptr; + + if (descr == 0) { + /* Found a reference to a free list entry. Ignore it. */ + return(orig_mark_stack_ptr); + } + /* In use counts were already updated when array descriptor was */ + /* pushed. Here we only replace it by subobject descriptors, so */ + /* no update is necessary. */ + new_mark_stack_ptr = GC_push_complex_descriptor(addr, descr, + mark_stack_ptr, + mark_stack_limit-1); + if (new_mark_stack_ptr == 0) { + /* Doesn't fit. Conservatively push the whole array as a unit */ + /* and request a mark stack expansion. */ + /* This cannot cause a mark stack overflow, since it replaces */ + /* the original array entry. */ + GC_mark_stack_too_small = TRUE; + new_mark_stack_ptr = orig_mark_stack_ptr + 1; + new_mark_stack_ptr -> mse_start = (ptr_t)addr; + new_mark_stack_ptr -> mse_descr = sz | GC_DS_LENGTH; + } else { + /* Push descriptor itself */ + new_mark_stack_ptr++; + new_mark_stack_ptr -> mse_start = (ptr_t)(addr + nwords - 1); + new_mark_stack_ptr -> mse_descr = sizeof(word) | GC_DS_LENGTH; + } + return new_mark_stack_ptr; +} + +GC_API GC_descr GC_CALL GC_make_descriptor(GC_bitmap bm, size_t len) +{ + signed_word last_set_bit = len - 1; + GC_descr result; + signed_word i; +# define HIGH_BIT (((word)1) << (WORDSZ - 1)) + + if (!GC_explicit_typing_initialized) GC_init_explicit_typing(); + while (last_set_bit >= 0 && !GC_get_bit(bm, last_set_bit)) + last_set_bit--; + if (last_set_bit < 0) return(0 /* no pointers */); +# if ALIGNMENT == CPP_WORDSZ/8 + { + register GC_bool all_bits_set = TRUE; + for (i = 0; i < last_set_bit; i++) { + if (!GC_get_bit(bm, i)) { + all_bits_set = FALSE; + break; + } + } + if (all_bits_set) { + /* An initial section contains all pointers. Use length descriptor. */ + return (WORDS_TO_BYTES(last_set_bit+1) | GC_DS_LENGTH); + } + } +# endif + if ((word)last_set_bit < BITMAP_BITS) { + /* Hopefully the common case. */ + /* Build bitmap descriptor (with bits reversed) */ + result = HIGH_BIT; + for (i = last_set_bit - 1; i >= 0; i--) { + result >>= 1; + if (GC_get_bit(bm, i)) result |= HIGH_BIT; + } + result |= GC_DS_BITMAP; + return(result); + } else { + signed_word index; + + index = GC_add_ext_descriptor(bm, (word)last_set_bit+1); + if (index == -1) return(WORDS_TO_BYTES(last_set_bit+1) | GC_DS_LENGTH); + /* Out of memory: use conservative */ + /* approximation. */ + result = GC_MAKE_PROC(GC_typed_mark_proc_index, (word)index); + return result; + } +} + +GC_API void * GC_CALL GC_malloc_explicitly_typed(size_t lb, GC_descr d) +{ + ptr_t op; + ptr_t * opp; + size_t lg; + DCL_LOCK_STATE; + + lb += TYPD_EXTRA_BYTES; + if(SMALL_OBJ(lb)) { + lg = GC_size_map[lb]; + opp = &(GC_eobjfreelist[lg]); + LOCK(); + if( (op = *opp) == 0 ) { + UNLOCK(); + op = (ptr_t)GENERAL_MALLOC((word)lb, GC_explicit_kind); + if (0 == op) return 0; + lg = GC_size_map[lb]; /* May have been uninitialized. */ + } else { + *opp = obj_link(op); + obj_link(op) = 0; + GC_bytes_allocd += GRANULES_TO_BYTES(lg); + UNLOCK(); + } + ((word *)op)[GRANULES_TO_WORDS(lg) - 1] = d; + } else { + op = (ptr_t)GENERAL_MALLOC((word)lb, GC_explicit_kind); + if (op != NULL) { + lg = BYTES_TO_GRANULES(GC_size(op)); + ((word *)op)[GRANULES_TO_WORDS(lg) - 1] = d; + } + } + return((void *) op); +} + +GC_API void * GC_CALL GC_malloc_explicitly_typed_ignore_off_page(size_t lb, + GC_descr d) +{ + ptr_t op; + ptr_t * opp; + size_t lg; + DCL_LOCK_STATE; + + lb += TYPD_EXTRA_BYTES; + if( SMALL_OBJ(lb) ) { + lg = GC_size_map[lb]; + opp = &(GC_eobjfreelist[lg]); + LOCK(); + if( (op = *opp) == 0 ) { + UNLOCK(); + op = (ptr_t)GENERAL_MALLOC_IOP(lb, GC_explicit_kind); + if (0 == op) return 0; + lg = GC_size_map[lb]; /* May have been uninitialized. */ + } else { + *opp = obj_link(op); + obj_link(op) = 0; + GC_bytes_allocd += GRANULES_TO_BYTES(lg); + UNLOCK(); + } + ((word *)op)[GRANULES_TO_WORDS(lg) - 1] = d; + } else { + op = (ptr_t)GENERAL_MALLOC_IOP(lb, GC_explicit_kind); + if (op != NULL) { + lg = BYTES_TO_WORDS(GC_size(op)); + ((word *)op)[GRANULES_TO_WORDS(lg) - 1] = d; + } + } + return((void *) op); +} + +GC_API void * GC_CALL GC_calloc_explicitly_typed(size_t n, size_t lb, + GC_descr d) +{ + ptr_t op; + ptr_t * opp; + size_t lg; + GC_descr simple_descr; + complex_descriptor *complex_descr; + register int descr_type; + struct LeafDescriptor leaf; + DCL_LOCK_STATE; + + descr_type = GC_make_array_descriptor((word)n, (word)lb, d, + &simple_descr, &complex_descr, &leaf); + switch(descr_type) { + case NO_MEM: return(0); + case SIMPLE: return(GC_malloc_explicitly_typed(n*lb, simple_descr)); + case LEAF: + lb *= n; + lb += sizeof(struct LeafDescriptor) + TYPD_EXTRA_BYTES; + break; + case COMPLEX: + lb *= n; + lb += TYPD_EXTRA_BYTES; + break; + } + if( SMALL_OBJ(lb) ) { + lg = GC_size_map[lb]; + opp = &(GC_arobjfreelist[lg]); + LOCK(); + if( (op = *opp) == 0 ) { + UNLOCK(); + op = (ptr_t)GENERAL_MALLOC((word)lb, GC_array_kind); + if (0 == op) return(0); + lg = GC_size_map[lb]; /* May have been uninitialized. */ + } else { + *opp = obj_link(op); + obj_link(op) = 0; + GC_bytes_allocd += GRANULES_TO_BYTES(lg); + UNLOCK(); + } + } else { + op = (ptr_t)GENERAL_MALLOC((word)lb, GC_array_kind); + if (0 == op) return(0); + lg = BYTES_TO_GRANULES(GC_size(op)); + } + if (descr_type == LEAF) { + /* Set up the descriptor inside the object itself. */ + volatile struct LeafDescriptor * lp = + (struct LeafDescriptor *) + ((word *)op + + GRANULES_TO_WORDS(lg) + - (BYTES_TO_WORDS(sizeof(struct LeafDescriptor)) + 1)); + + lp -> ld_tag = LEAF_TAG; + lp -> ld_size = leaf.ld_size; + lp -> ld_nelements = leaf.ld_nelements; + lp -> ld_descriptor = leaf.ld_descriptor; + ((volatile word *)op)[GRANULES_TO_WORDS(lg) - 1] = (word)lp; + } else { + size_t lw = GRANULES_TO_WORDS(lg); + + ((word *)op)[lw - 1] = (word)complex_descr; + /* Make sure the descriptor is cleared once there is any danger */ + /* it may have been collected. */ + if (GC_general_register_disappearing_link((void * *)((word *)op+lw-1), + op) == GC_NO_MEMORY) { + /* Couldn't register it due to lack of memory. Punt. */ + /* This will probably fail too, but gives the recovery code */ + /* a chance. */ + return(GC_malloc(n*lb)); + } + } + return((void *) op); +}