urem.S revision 1.1
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 #if defined(LIBC_SCCS) && !defined(lint) 34 /* .asciz "@(#)urem.s 8.1 (Berkeley) 6/4/93" */ 35 .asciz "$NetBSD: urem.S,v 1.1 2005/12/20 19:28:50 christos Exp $" 36 #endif /* LIBC_SCCS and not lint */ 37 38 #include "DEFS.h" 39 40 /* 41 * Unsigned modulus, PCC flavor. 42 * urem() takes an ordinary dividend/divisor pair; 43 * aurem() takes a pointer to a dividend and an ordinary divisor. 44 */ 45 46 #define DIVIDEND 4(%ap) 47 #define DIVISOR 8(%ap) 48 49 #ifdef __ELF__ 50 ASENTRY(__urem,0) 51 #else 52 ASENTRY(urem,0) 53 #endif 54 movl DIVISOR,%r2 55 jlss Leasy # big divisor: settle by comparison 56 movl DIVIDEND,%r0 57 jlss Lhard # big dividend: need extended division 58 divl3 %r2,%r0,%r1 # small divisor and dividend: signed modulus 59 mull2 %r2,%r1 60 subl2 %r1,%r0 61 ret 62 Lhard: 63 clrl %r1 64 ediv %r2,%r0,%r1,%r0 65 ret 66 Leasy: 67 subl3 %r2,DIVIDEND,%r0 68 jcc Ldifference # if divisor goes in once, return difference 69 movl DIVIDEND,%r0 # if divisor is bigger, return dividend 70 Ldifference: 71 ret 72 73 #ifdef __ELF__ 74 ASENTRY(__aurem,0) 75 #else 76 ASENTRY(aurem,0) 77 #endif 78 movl DIVIDEND,%r3 79 movl DIVISOR,%r2 80 jlss La_easy # big divisor: settle by comparison 81 movl (%r3),%r0 82 jlss La_hard # big dividend: need extended division 83 divl3 %r2,%r0,%r1 # small divisor and dividend: signed modulus 84 mull2 %r2,%r1 85 subl2 %r1,%r0 86 movl %r0,(%r3) # leave the value of the assignment in %r0 87 ret 88 La_hard: 89 clrl %r1 90 ediv %r2,%r0,%r1,%r0 91 movl %r0,(%r3) 92 ret 93 La_easy: 94 subl3 %r2,(%r3),%r0 95 jcs La_dividend # if divisor is bigger, leave dividend alone 96 movl %r0,(%r3) # if divisor goes in once, store difference 97 ret 98 La_dividend: 99 movl (%r3),%r0 100 ret 101
Indexes created Thu Oct 02 01:09:59 GMT 2025