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      1 /*	$NetBSD: mpyaccs.c,v 1.5 2012/02/04 17:03:10 skrll Exp $	*/
      2 
      3 /*	$OpenBSD: mpyaccs.c,v 1.4 2001/03/29 03:58:18 mickey Exp $	*/
      4 
      5 /*
      6  * Copyright 1996 1995 by Open Software Foundation, Inc.
      7  *              All Rights Reserved
      8  *
      9  * Permission to use, copy, modify, and distribute this software and
     10  * its documentation for any purpose and without fee is hereby granted,
     11  * provided that the above copyright notice appears in all copies and
     12  * that both the copyright notice and this permission notice appear in
     13  * supporting documentation.
     14  *
     15  * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
     16  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
     17  * FOR A PARTICULAR PURPOSE.
     18  *
     19  * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
     20  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
     21  * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
     22  * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
     23  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
     24  *
     25  */
     26 /*
     27  * pmk1.1
     28  */
     29 /*
     30  * (c) Copyright 1986 HEWLETT-PACKARD COMPANY
     31  *
     32  * To anyone who acknowledges that this file is provided "AS IS"
     33  * without any express or implied warranty:
     34  *     permission to use, copy, modify, and distribute this file
     35  * for any purpose is hereby granted without fee, provided that
     36  * the above copyright notice and this notice appears in all
     37  * copies, and that the name of Hewlett-Packard Company not be
     38  * used in advertising or publicity pertaining to distribution
     39  * of the software without specific, written prior permission.
     40  * Hewlett-Packard Company makes no representations about the
     41  * suitability of this software for any purpose.
     42  */
     43 
     44 #include <sys/cdefs.h>
     45 __KERNEL_RCSID(0, "$NetBSD: mpyaccs.c,v 1.5 2012/02/04 17:03:10 skrll Exp $");
     46 
     47 #include "md.h"
     48 
     49 void
     50 mpyaccs(int opnd1, int opnd2, struct mdsfu_register *result)
     51 {
     52 	struct mdsfu_register temp;
     53 	int carry, sign;
     54 
     55 	impys(&opnd1,&opnd2,&temp);
     56 
     57 	/* get result of low word add, and check for carry out */
     58 	if ((result_lo += (unsigned)temp.rslt_lo) < (unsigned)temp.rslt_lo)
     59 		carry = 1;
     60 	else carry = 0;
     61 
     62 	/* get result of high word add, and determine overflow status */
     63 	sign = result_hi ^ temp.rslt_hi;
     64 	result_hi += temp.rslt_hi + carry;
     65 	if (sign >= 0 && (temp.rslt_hi ^ result_hi) < 0) overflow = true;
     66 
     67 	return;
     68 }
     69