/* * Copyright (c) 1993 Winning Strategies, Inc. * 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 Winning Strategies, Inc. * 4. The name of the author may not 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 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. * * $FreeBSD$ */ #if defined(LIBC_RCS) && !defined(lint) .text .asciz "$FreeBSD$" #endif /* LIBC_RCS and not lint */ #include "DEFS.h" /* * memset(void *b, int c, size_t len) * write len bytes of value c (converted to an unsigned char) to * the string b. * * Written by: * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc. */ ENTRY(memset) pushl %edi pushl %ebx movl 12(%esp),%edi movzbl 16(%esp),%eax /* unsigned char, zero extend */ movl 20(%esp),%ecx pushl %edi /* push address of buffer */ cld /* set fill direction forward */ /* * if the string is too short, it's really not worth the overhead * of aligning to word boundries, etc. So we jump to a plain * unaligned set. */ cmpl $0x0f,%ecx jle L1 movb %al,%ah /* copy char to all bytes in word */ movl %eax,%edx sall $16,%eax orl %edx,%eax movl %edi,%edx /* compute misalignment */ negl %edx andl $3,%edx movl %ecx,%ebx subl %edx,%ebx movl %edx,%ecx /* set until word aligned */ rep stosb movl %ebx,%ecx shrl $2,%ecx /* set by words */ rep stosl movl %ebx,%ecx /* set remainder by bytes */ andl $3,%ecx L1: rep stosb popl %eax /* pop address of buffer */ popl %ebx popl %edi ret