/* $NetBSD: memset.S,v 1.4 2003/10/14 07:51:45 scw Exp $ */ /* * Copyright 2003 Wasabi Systems, Inc. * All rights reserved. * * Written by Steve C. Woodford for Wasabi Systems, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed for the NetBSD Project by * Wasabi Systems, Inc. * 4. The name of Wasabi Systems, Inc. may not be used to endorse * or promote products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (c) 1995 Mark Brinicombe. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Mark Brinicombe. * 4. The name of the company nor the name of the author may be used to * endorse or promote products derived from this software without specific * prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <machine/asm.h> .syntax unified /* * memset: Sets a block of memory to the specified value * * On entry: * r0 - dest address * r1 - byte to write * r2 - number of bytes to write * * On exit: * r0 - dest address */ #ifdef _BZERO /* LINTSTUB: Func: void bzero(void *, size_t) */ ENTRY(bzero) mov r3, #0x00 #else /* LINTSTUB: Func: void *memset(void *, int, size_t) */ ENTRY(memset) and r3, r1, #0xff /* We deal with bytes */ mov r1, r2 #endif cmp r1, #0x04 /* Do we have less than 4 bytes */ mov ip, r0 blt .Lmemset_lessthanfour /* Ok first we will word align the address */ ands r2, ip, #0x03 /* Get the bottom two bits */ bne .Lmemset_wordunaligned /* The address is not word aligned */ /* We are now word aligned */ .Lmemset_wordaligned: #ifndef _BZERO orr r3, r3, r3, lsl #8 /* Extend value to 16-bits */ #endif tst ip, #0x04 /* Quad-align for armv5e */ #ifndef _BZERO orr r3, r3, r3, lsl #16 /* Extend value to 32-bits */ #endif itt ne subne r1, r1, #0x04 /* Quad-align if necessary */ strne r3, [ip], #0x04 cmp r1, #0x10 blt .Lmemset_loop4 /* If less than 16 then use words */ mov r2, r3 /* Duplicate data */ cmp r1, #0x80 /* If < 128 then skip the big loop */ blt .Lmemset_loop32 /* Do 128 bytes at a time */ .Lmemset_loop128: subs r1, r1, #0x80 itttt ge strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 itttt ge strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 itttt ge strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 itttt ge strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 bgt .Lmemset_loop128 it eq RETeq /* Zero length so just exit */ add r1, r1, #0x80 /* Adjust for extra sub */ /* Do 32 bytes at a time */ .Lmemset_loop32: subs r1, r1, #0x20 itttt ge strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 bgt .Lmemset_loop32 it eq RETeq /* Zero length so just exit */ adds r1, r1, #0x10 /* Partially adjust for extra sub */ /* Deal with 16 bytes or more */ itt ge strdge r2, [ip], #0x08 strdge r2, [ip], #0x08 it eq RETeq /* Zero length so just exit */ it lt addlt r1, r1, #0x10 /* Possibly adjust for extra sub */ /* We have at least 4 bytes so copy as words */ .Lmemset_loop4: subs r1, r1, #0x04 it ge strge r3, [ip], #0x04 bgt .Lmemset_loop4 it eq RETeq /* Zero length so just exit */ /* Compensate for 64-bit alignment check */ adds r1, r1, #0x04 it eq RETeq cmp r1, #2 strb r3, [ip], #0x01 /* Set 1 byte */ it ge strbge r3, [ip], #0x01 /* Set another byte */ it gt strbgt r3, [ip] /* and a third */ RET /* Exit */ .Lmemset_wordunaligned: rsb r2, r2, #0x004 strb r3, [ip], #0x01 /* Set 1 byte */ cmp r2, #0x02 it ge strbge r3, [ip], #0x01 /* Set another byte */ sub r1, r1, r2 it gt strbgt r3, [ip], #0x01 /* and a third */ cmp r1, #0x04 /* More than 4 bytes left? */ it ge bge .Lmemset_wordaligned /* Yup */ .Lmemset_lessthanfour: cmp r1, #0x00 it eq RETeq /* Zero length so exit */ strb r3, [ip], #0x01 /* Set 1 byte */ cmp r1, #0x02 it ge strbge r3, [ip], #0x01 /* Set another byte */ it gt strbgt r3, [ip] /* and a third */ RET /* Exit */ #ifdef _BZERO END(bzero) #else END(memset) #endif .section .note.GNU-stack,"",%progbits
