111 lines
2.8 KiB
C
111 lines
2.8 KiB
C
/* $NetBSD: divsfm.c,v 1.1 2002/06/05 01:04:24 fredette Exp $ */
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/* $OpenBSD: divsfm.c,v 1.4 2001/03/29 03:58:17 mickey Exp $ */
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/*
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* Copyright 1996 1995 by Open Software Foundation, Inc.
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* All Rights Reserved
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*
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* Permission to use, copy, modify, and distribute this software and
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* its documentation for any purpose and without fee is hereby granted,
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* provided that the above copyright notice appears in all copies and
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* that both the copyright notice and this permission notice appear in
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* supporting documentation.
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*
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* OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
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* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE.
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*
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* IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
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* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
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* LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
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* NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
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* WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*
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*/
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/*
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* pmk1.1
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*/
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/*
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* (c) Copyright 1986 HEWLETT-PACKARD COMPANY
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*
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* To anyone who acknowledges that this file is provided "AS IS"
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* without any express or implied warranty:
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* permission to use, copy, modify, and distribute this file
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* for any purpose is hereby granted without fee, provided that
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* the above copyright notice and this notice appears in all
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* copies, and that the name of Hewlett-Packard Company not be
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* used in advertising or publicity pertaining to distribution
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* of the software without specific, written prior permission.
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* Hewlett-Packard Company makes no representations about the
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* suitability of this software for any purpose.
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*/
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#include "md.h"
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void
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divsfm(opnd1,opnd2,result)
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int opnd1, opnd2;
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struct mdsfu_register *result;
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{
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register int sign, op1_sign;
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/* check divisor for zero */
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if (opnd2 == 0) {
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overflow = TRUE;
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return;
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}
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/* get sign of result */
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sign = opnd1 ^ opnd2;
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/* get absolute value of operands */
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if (opnd1 < 0) {
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opnd1 = -opnd1;
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op1_sign = TRUE;
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}
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else op1_sign = FALSE;
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if (opnd2 < 0) opnd2 = -opnd2;
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/*
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* check for overflow
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*
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* if abs(opnd1) < 0, then opnd1 = -2**31
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* and abs(opnd1) >= abs(opnd2) always
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*/
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if (opnd1 >= opnd2 || opnd1 < 0) {
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/* check for opnd2 = -2**31 */
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if (opnd2 < 0 && opnd1 != opnd2) {
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result_hi = 0; /* remainder = 0 */
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result_lo = opnd1 << 1;
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}
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else {
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overflow = TRUE;
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return;
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}
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}
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else {
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/* do the divide */
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divu(opnd1,0,opnd2,result);
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/* return positive residue */
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if (op1_sign && result_hi) {
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result_hi = opnd2 - result_hi;
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result_lo++;
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}
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}
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/* check for overflow */
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if (result_lo < 0) {
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overflow = TRUE;
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return;
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}
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overflow = FALSE;
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/* return appropriately signed result */
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if (sign<0) result_lo = -result_lo;
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return;
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}
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