1/* $NetBSD: memset.S,v 1.4 2003/10/14 07:51:45 scw Exp $ */ 2 3/* 4 * Copyright 2003 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Steve C. Woodford for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37/* 38 * Copyright (c) 1995 Mark Brinicombe. 39 * All rights reserved. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. All advertising materials mentioning features or use of this software 50 * must display the following acknowledgement: 51 * This product includes software developed by Mark Brinicombe. 52 * 4. The name of the company nor the name of the author may be used to 53 * endorse or promote products derived from this software without specific 54 * prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 57 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 58 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 59 * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 60 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 61 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 62 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 63 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 64 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 65 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 66 * SUCH DAMAGE. 67 */ 68 69#include <machine/asm.h> 70__FBSDID("$FreeBSD$"); 71 72.syntax unified 73 74/* 75 * memset: Sets a block of memory to the specified value 76 * 77 * On entry: 78 * r0 - dest address 79 * r1 - byte to write 80 * r2 - number of bytes to write 81 * 82 * On exit: 83 * r0 - dest address 84 */ 85#ifdef _BZERO 86/* LINTSTUB: Func: void bzero(void *, size_t) */ 87ENTRY(bzero) 88 mov r3, #0x00 89#else 90/* LINTSTUB: Func: void *memset(void *, int, size_t) */ 91ENTRY(memset) 92 and r3, r1, #0xff /* We deal with bytes */ 93 mov r1, r2 94#endif 95 cmp r1, #0x04 /* Do we have less than 4 bytes */ 96 mov ip, r0 97 blt .Lmemset_lessthanfour 98 99 /* Ok first we will word align the address */ 100 ands r2, ip, #0x03 /* Get the bottom two bits */ 101 bne .Lmemset_wordunaligned /* The address is not word aligned */ 102 103 /* We are now word aligned */ 104.Lmemset_wordaligned: 105#ifndef _BZERO 106 orr r3, r3, r3, lsl #8 /* Extend value to 16-bits */ 107#endif 108 tst ip, #0x04 /* Quad-align for armv5e */ 109#ifndef _BZERO 110 orr r3, r3, r3, lsl #16 /* Extend value to 32-bits */ 111#endif 112 itt ne 113 subne r1, r1, #0x04 /* Quad-align if necessary */ 114 strne r3, [ip], #0x04 115 cmp r1, #0x10 116 blt .Lmemset_loop4 /* If less than 16 then use words */ 117 mov r2, r3 /* Duplicate data */ 118 cmp r1, #0x80 /* If < 128 then skip the big loop */ 119 blt .Lmemset_loop32 120 121 /* Do 128 bytes at a time */ 122.Lmemset_loop128: 123 subs r1, r1, #0x80 124 itttt ge 125 strdge r2, [ip], #0x08 126 strdge r2, [ip], #0x08 127 strdge r2, [ip], #0x08 128 strdge r2, [ip], #0x08 129 itttt ge 130 strdge r2, [ip], #0x08 131 strdge r2, [ip], #0x08 132 strdge r2, [ip], #0x08 133 strdge r2, [ip], #0x08 134 itttt ge 135 strdge r2, [ip], #0x08 136 strdge r2, [ip], #0x08 137 strdge r2, [ip], #0x08 138 strdge r2, [ip], #0x08 139 itttt ge 140 strdge r2, [ip], #0x08 141 strdge r2, [ip], #0x08 142 strdge r2, [ip], #0x08 143 strdge r2, [ip], #0x08 144 bgt .Lmemset_loop128 145 it eq 146 RETeq /* Zero length so just exit */ 147 148 add r1, r1, #0x80 /* Adjust for extra sub */ 149 150 /* Do 32 bytes at a time */ 151.Lmemset_loop32: 152 subs r1, r1, #0x20 153 itttt ge 154 strdge r2, [ip], #0x08 155 strdge r2, [ip], #0x08 156 strdge r2, [ip], #0x08 157 strdge r2, [ip], #0x08 158 bgt .Lmemset_loop32 159 it eq 160 RETeq /* Zero length so just exit */ 161 162 adds r1, r1, #0x10 /* Partially adjust for extra sub */ 163 164 /* Deal with 16 bytes or more */ 165 itt ge 166 strdge r2, [ip], #0x08 167 strdge r2, [ip], #0x08 168 it eq 169 RETeq /* Zero length so just exit */ 170 171 it lt 172 addlt r1, r1, #0x10 /* Possibly adjust for extra sub */ 173 174 /* We have at least 4 bytes so copy as words */ 175.Lmemset_loop4: 176 subs r1, r1, #0x04 177 it ge 178 strge r3, [ip], #0x04 179 bgt .Lmemset_loop4 180 it eq 181 RETeq /* Zero length so just exit */ 182 183 /* Compensate for 64-bit alignment check */ 184 adds r1, r1, #0x04 185 it eq 186 RETeq 187 cmp r1, #2 188 189 strb r3, [ip], #0x01 /* Set 1 byte */ 190 it ge 191 strbge r3, [ip], #0x01 /* Set another byte */ 192 it gt 193 strbgt r3, [ip] /* and a third */ 194 RET /* Exit */ 195 196.Lmemset_wordunaligned: 197 rsb r2, r2, #0x004 198 strb r3, [ip], #0x01 /* Set 1 byte */ 199 cmp r2, #0x02 200 it ge 201 strbge r3, [ip], #0x01 /* Set another byte */ 202 sub r1, r1, r2 203 it gt 204 strbgt r3, [ip], #0x01 /* and a third */ 205 cmp r1, #0x04 /* More than 4 bytes left? */ 206 it ge 207 bge .Lmemset_wordaligned /* Yup */ 208 209.Lmemset_lessthanfour: 210 cmp r1, #0x00 211 it eq 212 RETeq /* Zero length so exit */ 213 strb r3, [ip], #0x01 /* Set 1 byte */ 214 cmp r1, #0x02 215 it ge 216 strbge r3, [ip], #0x01 /* Set another byte */ 217 it gt 218 strbgt r3, [ip] /* and a third */ 219 RET /* Exit */ 220#ifdef _BZERO 221END(bzero) 222#else 223END(memset) 224#endif 225 226 .section .note.GNU-stack,"",%progbits 227