Return to gc_typed.h CVS log

Up to [local] / OpenXM_contrib / gc

Annotation of OpenXM_contrib/gc/gc_typed.h, Revision 1.1.1.2

1.1       maekawa     1: /*
                      2:  * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
                      3:  * Copyright (c) 1991-1994 by Xerox Corporation.  All rights reserved.
                      4:  * Copyright 1996 Silicon Graphics.  All rights reserved.
                      5:  *
                      6:  * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
                      7:  * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
                      8:  *
                      9:  * Permission is hereby granted to use or copy this program
                     10:  * for any purpose,  provided the above notices are retained on all copies.
                     11:  * Permission to modify the code and to distribute modified code is granted,
                     12:  * provided the above notices are retained, and a notice that the code was
                     13:  * modified is included with the above copyright notice.
                     14:  */
                     15: /*
                     16:  * Some simple primitives for allocation with explicit type information.
                     17:  * Facilities for dynamic type inference may be added later.
                     18:  * Should be used only for extremely performance critical applications,
                     19:  * or if conservative collector leakage is otherwise a problem (unlikely).
                     20:  * Note that this is implemented completely separately from the rest
                     21:  * of the collector, and is not linked in unless referenced.
                     22:  * This does not currently support GC_DEBUG in any interesting way.
                     23:  */
                     24: /* Boehm, May 19, 1994 2:13 pm PDT */
                     25:
                     26: #ifndef _GC_TYPED_H
                     27: # define _GC_TYPED_H
                     28: # ifndef _GC_H
                     29: #   include "gc.h"
                     30: # endif
                     31:
                     32: typedef GC_word * GC_bitmap;
                     33:        /* The least significant bit of the first word is one if        */
                     34:        /* the first word in the object may be a pointer.               */
                     35:
                     36: # define GC_get_bit(bm, index) \
                     37:                (((bm)[divWORDSZ(index)] >> modWORDSZ(index)) & 1)
                     38: # define GC_set_bit(bm, index) \
                     39:                (bm)[divWORDSZ(index)] |= (word)1 << modWORDSZ(index)
                     40:
                     41: typedef GC_word GC_descr;
                     42:
                     43: GC_API GC_descr GC_make_descriptor GC_PROTO((GC_bitmap bm, size_t len));
                     44:                /* Return a type descriptor for the object whose layout */
                     45:                /* is described by the argument.                        */
                     46:                /* The least significant bit of the first word is one   */
                     47:                /* if the first word in the object may be a pointer.    */
                     48:                /* The second argument specifies the number of          */
                     49:                /* meaningful bits in the bitmap.  The actual object    */
                     50:                /* may be larger (but not smaller).  Any additional     */
                     51:                /* words in the object are assumed not to contain       */
                     52:                /* pointers.                                            */
                     53:                /* Returns a conservative approximation in the          */
                     54:                /* (unlikely) case of insufficient memory to build      */
                     55:                /* the descriptor.  Calls to GC_make_descriptor         */
                     56:                /* may consume some amount of a finite resource.  This  */
                     57:                /* is intended to be called once per type, not once     */
                     58:                /* per allocation.                                      */
                     59:
                     60: GC_API GC_PTR GC_malloc_explicitly_typed
                     61:                        GC_PROTO((size_t size_in_bytes, GC_descr d));
                     62:                /* Allocate an object whose layout is described by d.   */
                     63:                /* The resulting object MAY NOT BE PASSED TO REALLOC.   */
1.1.1.2 ! maekawa    64:                /* The returned object is cleared.                      */
1.1       maekawa    65:
                     66: GC_API GC_PTR GC_malloc_explicitly_typed_ignore_off_page
                     67:                         GC_PROTO((size_t size_in_bytes, GC_descr d));
                     68:
                     69: GC_API GC_PTR GC_calloc_explicitly_typed
                     70:                        GC_PROTO((size_t nelements,
                     71:                                  size_t element_size_in_bytes,
                     72:                                  GC_descr d));
                     73:        /* Allocate an array of nelements elements, each of the */
                     74:        /* given size, and with the given descriptor.           */
                     75:        /* The elemnt size must be a multiple of the byte       */
                     76:        /* alignment required for pointers.  E.g. on a 32-bit   */
                     77:        /* machine with 16-bit aligned pointers, size_in_bytes  */
                     78:        /* must be a multiple of 2.                             */
1.1.1.2 ! maekawa    79:        /* Returned object is cleared.                          */
1.1       maekawa    80:
                     81: #ifdef GC_DEBUG
                     82: #   define GC_MALLOC_EXPLICTLY_TYPED(bytes, d) GC_MALLOC(bytes)
                     83: #   define GC_CALLOC_EXPLICTLY_TYPED(n, bytes, d) GC_MALLOC(n*bytes)
                     84: #else
                     85: #  define GC_MALLOC_EXPLICTLY_TYPED(bytes, d) \
                     86:        GC_malloc_explicitly_typed(bytes, d)
                     87: #  define GC_CALLOC_EXPLICTLY_TYPED(n, bytes, d) \
                     88:        GC_calloc_explicitly_typed(n, bytes, d)
                     89: #endif /* !GC_DEBUG */
                     90:
                     91:
                     92: #endif /* _GC_TYPED_H */
                     93: