1/* $NetBSD: memset.S,v 1.6 2013/11/30 21:09:11 joerg 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 71#if defined(__ARM_EABI__) && !defined(BZER0) 72STRONG_ALIAS(__aeabi_memset, memset) 73#endif 74 75/* 76 * memset: Sets a block of memory to the specified value 77 * 78 * On entry: 79 * r0 - dest address 80 * r1 - byte to write 81 * r2 - number of bytes to write 82 * 83 * On exit: 84 * r0 - dest address 85 */ 86#ifdef _BZERO 87/* LINTSTUB: Func: void bzero(void *, size_t) */ 88ENTRY(bzero) 89 mov r3, #0x00 90#else 91/* LINTSTUB: Func: void *memset(void *, int, size_t) */ 92ENTRY(memset) 93 and r3, r1, #0xff /* We deal with bytes */ 94 mov r1, r2 95#endif 96 cmp r1, #0x04 /* Do we have less than 4 bytes */ 97 mov ip, r0 98 blt .Lmemset_lessthanfour 99 100 /* Ok first we will word align the address */ 101 ands r2, ip, #0x03 /* Get the bottom two bits */ 102 bne .Lmemset_wordunaligned /* The address is not word aligned */ 103 104 /* We are now word aligned */ 105.Lmemset_wordaligned: 106#ifndef _BZERO 107 orr r3, r3, r3, lsl #8 /* Extend value to 16-bits */ 108#endif 109#ifdef _ARM_ARCH_DWORD_OK 110 tst ip, #0x04 /* Quad-align for Xscale */ 111#else 112 cmp r1, #0x10 113#endif 114#ifndef _BZERO 115 orr r3, r3, r3, lsl #16 /* Extend value to 32-bits */ 116#endif 117#ifdef _ARM_ARCH_DWORD_OK 118 subne r1, r1, #0x04 /* Quad-align if necessary */ 119 strne r3, [ip], #0x04 120 cmp r1, #0x10 121#endif 122 blt .Lmemset_loop4 /* If less than 16 then use words */ 123 mov r2, r3 /* Duplicate data */ 124 cmp r1, #0x80 /* If < 128 then skip the big loop */ 125 blt .Lmemset_loop32 126 127 /* Do 128 bytes at a time */ 128.Lmemset_loop128: 129 subs r1, r1, #0x80 130#ifdef _ARM_ARCH_DWORD_OK 131 strdge r2, r3, [ip], #0x08 132 strdge r2, r3, [ip], #0x08 133 strdge r2, r3, [ip], #0x08 134 strdge r2, r3, [ip], #0x08 135 strdge r2, r3, [ip], #0x08 136 strdge r2, r3, [ip], #0x08 137 strdge r2, r3, [ip], #0x08 138 strdge r2, r3, [ip], #0x08 139 strdge r2, r3, [ip], #0x08 140 strdge r2, r3, [ip], #0x08 141 strdge r2, r3, [ip], #0x08 142 strdge r2, r3, [ip], #0x08 143 strdge r2, r3, [ip], #0x08 144 strdge r2, r3, [ip], #0x08 145 strdge r2, r3, [ip], #0x08 146 strdge r2, r3, [ip], #0x08 147#else 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 stmiage ip!, {r2-r3} 164#endif 165 bgt .Lmemset_loop128 166 RETc(eq) /* Zero length so just exit */ 167 168 add r1, r1, #0x80 /* Adjust for extra sub */ 169 170 /* Do 32 bytes at a time */ 171.Lmemset_loop32: 172 subs r1, r1, #0x20 173#ifdef _ARM_ARCH_DWORD_OK 174 strdge r2, r3, [ip], #0x08 175 strdge r2, r3, [ip], #0x08 176 strdge r2, r3, [ip], #0x08 177 strdge r2, r3, [ip], #0x08 178#else 179 stmiage ip!, {r2-r3} 180 stmiage ip!, {r2-r3} 181 stmiage ip!, {r2-r3} 182 stmiage ip!, {r2-r3} 183#endif 184 bgt .Lmemset_loop32 185 RETc(eq) /* Zero length so just exit */ 186 187 adds r1, r1, #0x10 /* Partially adjust for extra sub */ 188 189 /* Deal with 16 bytes or more */ 190#ifdef _ARM_ARCH_DWORD_OK 191 strdge r2, r3, [ip], #0x08 192 strdge r2, r3, [ip], #0x08 193#else 194 stmiage ip!, {r2-r3} 195 stmiage ip!, {r2-r3} 196#endif 197 RETc(eq) /* Zero length so just exit */ 198 199 addlt r1, r1, #0x10 /* Possibly adjust for extra sub */ 200 201 /* We have at least 4 bytes so copy as words */ 202.Lmemset_loop4: 203 subs r1, r1, #0x04 204 strge r3, [ip], #0x04 205 bgt .Lmemset_loop4 206 RETc(eq) /* Zero length so just exit */ 207 208#ifdef _ARM_ARCH_DWORD_OK 209 /* Compensate for 64-bit alignment check */ 210 adds r1, r1, #0x04 211 RETc(eq) 212 cmp r1, #2 213#else 214 cmp r1, #-2 215#endif 216 217 strb r3, [ip], #0x01 /* Set 1 byte */ 218 strbge r3, [ip], #0x01 /* Set another byte */ 219 strbgt r3, [ip] /* and a third */ 220 RET /* Exit */ 221 222.Lmemset_wordunaligned: 223 rsb r2, r2, #0x004 224 strb r3, [ip], #0x01 /* Set 1 byte */ 225 cmp r2, #0x02 226 strbge r3, [ip], #0x01 /* Set another byte */ 227 sub r1, r1, r2 228 strbgt r3, [ip], #0x01 /* and a third */ 229 cmp r1, #0x04 /* More than 4 bytes left? */ 230 bge .Lmemset_wordaligned /* Yup */ 231 232.Lmemset_lessthanfour: 233 cmp r1, #0x00 234 RETc(eq) /* Zero length so exit */ 235 strb r3, [ip], #0x01 /* Set 1 byte */ 236 cmp r1, #0x02 237 strbge r3, [ip], #0x01 /* Set another byte */ 238 strbgt r3, [ip] /* and a third */ 239 RET /* Exit */ 240#ifdef _BZERO 241END(bzero) 242#else 243END(memset) 244#endif 245