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#ifdef _ARM_ARCH_5E 109 tst ip, #0x04 /* Quad-align for armv5e */ 110#else 111 cmp r1, #0x10 112#endif 113#ifndef _BZERO 114 orr r3, r3, r3, lsl #16 /* Extend value to 32-bits */ 115#endif 116#ifdef _ARM_ARCH_5E 117 subne r1, r1, #0x04 /* Quad-align if necessary */ 118 strne r3, [ip], #0x04 119 cmp r1, #0x10 120#endif 121 blt .Lmemset_loop4 /* If less than 16 then use words */ 122 mov r2, r3 /* Duplicate data */ 123 cmp r1, #0x80 /* If < 128 then skip the big loop */ 124 blt .Lmemset_loop32 125 126 /* Do 128 bytes at a time */ 127.Lmemset_loop128: 128 subs r1, r1, #0x80 129#ifdef _ARM_ARCH_5E 130 strdge r2, [ip], #0x08 131 strdge r2, [ip], #0x08 132 strdge r2, [ip], #0x08 133 strdge r2, [ip], #0x08 134 strdge r2, [ip], #0x08 135 strdge r2, [ip], #0x08 136 strdge r2, [ip], #0x08 137 strdge r2, [ip], #0x08 138 strdge r2, [ip], #0x08 139 strdge r2, [ip], #0x08 140 strdge r2, [ip], #0x08 141 strdge r2, [ip], #0x08 142 strdge r2, [ip], #0x08 143 strdge r2, [ip], #0x08 144 strdge r2, [ip], #0x08 145 strdge r2, [ip], #0x08 146#else 147 stmiage ip!, {r2-r3} 148 stmiage ip!, {r2-r3} 149 stmiage ip!, {r2-r3} 150 stmiage ip!, {r2-r3} 151 stmiage ip!, {r2-r3} 152 stmiage ip!, {r2-r3} 153 stmiage ip!, {r2-r3} 154 stmiage ip!, {r2-r3} 155 stmiage ip!, {r2-r3} 156 stmiage ip!, {r2-r3} 157 stmiage ip!, {r2-r3} 158 stmiage ip!, {r2-r3} 159 stmiage ip!, {r2-r3} 160 stmiage ip!, {r2-r3} 161 stmiage ip!, {r2-r3} 162 stmiage ip!, {r2-r3} 163#endif 164 bgt .Lmemset_loop128 165 RETeq /* Zero length so just exit */ 166 167 add r1, r1, #0x80 /* Adjust for extra sub */ 168 169 /* Do 32 bytes at a time */ 170.Lmemset_loop32: 171 subs r1, r1, #0x20 172#ifdef _ARM_ARCH_5E 173 strdge r2, [ip], #0x08 174 strdge r2, [ip], #0x08 175 strdge r2, [ip], #0x08 176 strdge r2, [ip], #0x08 177#else 178 stmiage ip!, {r2-r3} 179 stmiage ip!, {r2-r3} 180 stmiage ip!, {r2-r3} 181 stmiage ip!, {r2-r3} 182#endif 183 bgt .Lmemset_loop32 184 RETeq /* Zero length so just exit */ 185 186 adds r1, r1, #0x10 /* Partially adjust for extra sub */ 187 188 /* Deal with 16 bytes or more */ 189#ifdef _ARM_ARCH_5E 190 strdge r2, [ip], #0x08 191 strdge r2, [ip], #0x08 192#else 193 stmiage ip!, {r2-r3} 194 stmiage ip!, {r2-r3} 195#endif 196 RETeq /* Zero length so just exit */ 197 198 addlt r1, r1, #0x10 /* Possibly adjust for extra sub */ 199 200 /* We have at least 4 bytes so copy as words */ 201.Lmemset_loop4: 202 subs r1, r1, #0x04 203 strge r3, [ip], #0x04 204 bgt .Lmemset_loop4 205 RETeq /* Zero length so just exit */ 206 207#ifdef _ARM_ARCH_5E 208 /* Compensate for 64-bit alignment check */ 209 adds r1, r1, #0x04 210 RETeq 211 cmp r1, #2 212#else 213 cmp r1, #-2 214#endif 215 216 strb r3, [ip], #0x01 /* Set 1 byte */ 217 strbge r3, [ip], #0x01 /* Set another byte */ 218 strbgt r3, [ip] /* and a third */ 219 RET /* Exit */ 220 221.Lmemset_wordunaligned: 222 rsb r2, r2, #0x004 223 strb r3, [ip], #0x01 /* Set 1 byte */ 224 cmp r2, #0x02 225 strbge r3, [ip], #0x01 /* Set another byte */ 226 sub r1, r1, r2 227 strbgt r3, [ip], #0x01 /* and a third */ 228 cmp r1, #0x04 /* More than 4 bytes left? */ 229 bge .Lmemset_wordaligned /* Yup */ 230 231.Lmemset_lessthanfour: 232 cmp r1, #0x00 233 RETeq /* Zero length so exit */ 234 strb r3, [ip], #0x01 /* Set 1 byte */ 235 cmp r1, #0x02 236 strbge r3, [ip], #0x01 /* Set another byte */ 237 strbgt r3, [ip] /* and a third */ 238 RET /* Exit */ 239#ifdef _BZERO 240END(bzero) 241#else 242END(memset) 243#endif 244