gc_inl.h   [plain text]

/* 
 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
 * Copyright (c) 1991-1995 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, October 3, 1995 2:07 pm PDT */
 
# ifndef GC_PRIVATE_H
#   include "private/gc_priv.h"
# endif

/* USE OF THIS FILE IS NOT RECOMMENDED unless GC_all_interior_pointers	*/
/* is always set, or the collector has been built with			*/
/* -DDONT_ADD_BYTE_AT_END, or the specified size includes a pointerfree	*/
/* word at the end.  In the standard collector configuration,		*/
/* the final word of each object may not be scanned.			*/
/* This iinterface is most useful for compilers that generate C.	*/
/* Manual use is hereby discouraged.					*/

/* Allocate n words (NOT BYTES).  X is made to point to the result.	*/
/* It is assumed that n < MAXOBJSZ, and					*/
/* that n > 0.  On machines requiring double word alignment of some	*/
/* data, we also assume that n is 1 or even.				*/
/* If the collector is built with -DUSE_MARK_BYTES or -DPARALLEL_MARK,	*/
/* the n = 1 case is also disallowed.					*/
/* Effectively this means that portable code should make sure n is even.*/
/* This bypasses the							*/
/* MERGE_SIZES mechanism.  In order to minimize the number of distinct	*/
/* free lists that are maintained, the caller should ensure that a 	*/
/* small number of distinct values of n are used.  (The MERGE_SIZES	*/
/* mechanism normally does this by ensuring that only the leading three	*/
/* bits of n may be nonzero.  See misc.c for details.)  We really 	*/
/* recommend this only in cases in which n is a constant, and no	*/
/* locking is required.							*/
/* In that case it may allow the compiler to perform substantial	*/
/* additional optimizations.						*/
# define GC_MALLOC_WORDS(result,n) \
{	\
    register ptr_t op;	\
    register ptr_t *opp;	\
    DCL_LOCK_STATE;	\
	\
    opp = &(GC_objfreelist[n]);	\
    FASTLOCK();	\
    if( !FASTLOCK_SUCCEEDED() || (op = *opp) == 0 ) {	\
        FASTUNLOCK();	\
        (result) = GC_generic_malloc_words_small((n), NORMAL);	\
    } else { 	\
        *opp = obj_link(op);	\
        obj_link(op) = 0;	\
        GC_words_allocd += (n);	\
        FASTUNLOCK();	\
        (result) = (GC_PTR) op;	\
    }	\
}


/* The same for atomic objects:	*/
# define GC_MALLOC_ATOMIC_WORDS(result,n) \
{	\
    register ptr_t op;	\
    register ptr_t *opp;	\
    DCL_LOCK_STATE;	\
	\
    opp = &(GC_aobjfreelist[n]);	\
    FASTLOCK();	\
    if( !FASTLOCK_SUCCEEDED() || (op = *opp) == 0 ) {	\
        FASTUNLOCK();	\
        (result) = GC_generic_malloc_words_small((n), PTRFREE);	\
    } else { 	\
        *opp = obj_link(op);	\
        obj_link(op) = 0;	\
        GC_words_allocd += (n);	\
        FASTUNLOCK();	\
        (result) = (GC_PTR) op;	\
    }	\
}

/* And once more for two word initialized objects: */
# define GC_CONS(result, first, second) \
{	\
    register ptr_t op;	\
    register ptr_t *opp;	\
    DCL_LOCK_STATE;	\
	\
    opp = &(GC_objfreelist[2]);	\
    FASTLOCK();	\
    if( !FASTLOCK_SUCCEEDED() || (op = *opp) == 0 ) {	\
        FASTUNLOCK();	\
        op = GC_generic_malloc_words_small(2, NORMAL);	\
    } else {	\
        *opp = obj_link(op);	\
        GC_words_allocd += 2;	\
        FASTUNLOCK();	\
    } \
    ((word *)op)[0] = (word)(first);	\
    ((word *)op)[1] = (word)(second);	\
    (result) = (GC_PTR) op;	\
}