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/* $OpenBSD: udiv.s,v 1.2 1997/05/29 00:05:26 niklas Exp $ */
/* $NetBSD: udiv.s,v 1.2 1994/10/26 08:03:34 cgd Exp $ */
/*-
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Donn Seeley at UUNET Technologies, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)udiv.s 5.6 (Berkeley) 4/15/91
*/
/*
* Unsigned division, PCC flavor.
* udiv() takes an ordinary dividend/divisor pair;
* audiv() takes a pointer to a dividend and an ordinary divisor.
*/
#define DIVIDEND 4(ap)
#define DIVISOR 8(ap)
.globl udiv
.align 2
udiv: .word 0x0
movl DIVISOR,r2
jlss Leasy # big divisor: settle by comparison
movl DIVIDEND,r0
jlss Lhard # big dividend: extended division
divl2 r2,r0 # small divisor and dividend: signed division
ret
Lhard:
clrl r1
ediv r2,r0,r0,r1
ret
Leasy:
cmpl DIVIDEND,r2
jgequ Lone # if dividend is as big or bigger, return 1
clrl r0 # else return 0
ret
Lone:
movl $1,r0
ret
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