1/* $NetBSD: memset.S,v 1.2 2008/04/28 20:22:52 martin Exp $ */ 2 3/*- 4 * Copyright (c) 1997 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by J.T. Conklin. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32/*- 33 * Copyright (c) 1990 The Regents of the University of California. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to Berkeley by 37 * the Systems Programming Group of the University of Utah Computer 38 * Science Department. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. Neither the name of the University nor the names of its contributors 49 * may be used to endorse or promote products derived from this software 50 * without specific prior written permission. 51 * 52 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 55 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 62 * SUCH DAMAGE. 63 */ 64 65#include <machine/asm.h> 66 67#if defined(LIBC_SCCS) && !defined(lint) 68#if 0 69 RCSID("from: @(#)bzero.s 5.1 (Berkeley) 5/12/90") 70#else 71 RCSID("$NetBSD: memset.S,v 1.2 2008/04/28 20:22:52 martin Exp $") 72#endif 73#endif /* LIBC_SCCS and not lint */ 74 75ENTRY(memset) 76 movl %d2,%sp@- 77 movl %sp@(8),%a0 | destination 78 movl %sp@(16),%d1 | count 79 movb %sp@(15),%d2 | character 80 81 /* 82 * It isn't worth the overhead of aligning to {long}word boundries 83 * if the string is too short. 84 */ 85 cmpl #15,%d1 86 jlt Lbzbyte 87 88 clrl %d0 | replicate byte to fill longword 89 movb %d2,%d0 90 movl %d0,%d2 91 lsll #8,%d0 92 orl %d0,%d2 93 lsll #8,%d0 94 orl %d0,%d2 95 lsll #8,%d0 96 orl %d0,%d2 97 98 /* word align */ 99 movl %a0,%d0 100 btst #0,%d0 | if (dst & 1) 101 jeq Lbzalgndw | 102 movb %d2,%a0@+ | *(char *)dst++ = X 103 subql #1,%d1 | len-- 104 addql #1,%d0 105Lbzalgndw: 106#ifndef __mc68010__ 107 /* long word align */ 108 btst #1,%d0 | if (dst & 2) 109 jeq Lbzalgndl | 110 movw %d2,%a0@+ | *(short *)dst++ = X 111 subql #2,%d1 | len -= 2 112Lbzalgndl: 113 /* set by 8 longwords */ 114 movel %d1,%d0 115 lsrl #5,%d0 | cnt = len / 32 116 jeq Lbzlong | if (cnt) 117 andl #31,%d1 | len %= 32 118 subql #1,%d0 | set up for dbf 119Lbz32loop: 120 movl %d2,%a0@+ | set 8 long words 121 movl %d2,%a0@+ 122 movl %d2,%a0@+ 123 movl %d2,%a0@+ 124 movl %d2,%a0@+ 125 movl %d2,%a0@+ 126 movl %d2,%a0@+ 127 movl %d2,%a0@+ 128 dbf %d0,Lbz32loop | till done 129 clrw %d0 130 subql #1,%d0 131 jcc Lbz32loop 132#endif /* !__mc68010__ */ 133 134Lbzlong: 135 /* set by longwords */ 136 movel %d1,%d0 137 lsrl #2,%d0 | cnt = len / 4 138 jeq Lbzbyte | if (cnt) 139 subql #1,%d0 | set up for dbf 140Lbzlloop: 141 movl %d2,%a0@+ | clear longwords 142 dbf %d0,Lbzlloop | till done 143#ifdef __mc68010__ 144 clrw %d0 145 subql #1,%d0 146 jcc Lbzlloop 147#endif /* __mc68010__ */ 148 andl #3,%d1 | len %= 4 149 jeq Lbzdone 150 151 subql #1,%d1 | set up for dbf 152Lbzbloop: 153 movb %d2,%a0@+ | set bytes 154Lbzbyte: 155 dbf %d1,Lbzbloop | till done 156Lbzdone: 157 movl %sp@(8),%d0 | return destination 158#ifdef __SVR4_ABI__ 159 moveal %d0,%a0 160#endif 161 movl %sp@+,%d2 162 rts 163