1/*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Donn Seeley at UUNET Technologies, Inc. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33#include <machine/asm.h> 34 35 /* .asciz "@(#)urem.s 8.1 (Berkeley) 6/4/93" */ 36RCSID("$NetBSD: urem.S,v 1.3 2011/01/25 04:45:28 matt Exp $") 37 38/* 39 * Unsigned modulus, PCC flavor. 40 * urem() takes an ordinary dividend/divisor pair; 41 * aurem() takes a pointer to a dividend and an ordinary divisor. 42 */ 43 44#define DIVIDEND 4(%ap) 45#define DIVISOR 8(%ap) 46 47ASENTRY(__urem,0) 48 movl DIVISOR,%r2 49 jlss Leasy # big divisor: settle by comparison 50 movl DIVIDEND,%r0 51 jlss Lhard # big dividend: need extended division 52 divl3 %r2,%r0,%r1 # small divisor and dividend: signed modulus 53 mull2 %r2,%r1 54 subl2 %r1,%r0 55 ret 56Lhard: 57 clrl %r1 58 ediv %r2,%r0,%r1,%r0 59 ret 60Leasy: 61 subl3 %r2,DIVIDEND,%r0 62 jcc Ldifference # if divisor goes in once, return difference 63 movl DIVIDEND,%r0 # if divisor is bigger, return dividend 64Ldifference: 65 ret 66END(__urem) 67 68ASENTRY(__aurem,0) 69 movl DIVIDEND,%r3 70 movl DIVISOR,%r2 71 jlss La_easy # big divisor: settle by comparison 72 movl (%r3),%r0 73 jlss La_hard # big dividend: need extended division 74 divl3 %r2,%r0,%r1 # small divisor and dividend: signed modulus 75 mull2 %r2,%r1 76 subl2 %r1,%r0 77 movl %r0,(%r3) # leave the value of the assignment in %r0 78 ret 79La_hard: 80 clrl %r1 81 ediv %r2,%r0,%r1,%r0 82 movl %r0,(%r3) 83 ret 84La_easy: 85 subl3 %r2,(%r3),%r0 86 jcs La_dividend # if divisor is bigger, leave dividend alone 87 movl %r0,(%r3) # if divisor goes in once, store difference 88 ret 89La_dividend: 90 movl (%r3),%r0 91 ret 92END(__aurem) 93