11849Swollman/* 21849Swollman * Copyright (c) 1993 Winning Strategies, Inc. 31849Swollman * All rights reserved. 41849Swollman * 51849Swollman * Redistribution and use in source and binary forms, with or without 61849Swollman * modification, are permitted provided that the following conditions 71849Swollman * are met: 81849Swollman * 1. Redistributions of source code must retain the above copyright 91849Swollman * notice, this list of conditions and the following disclaimer. 101849Swollman * 2. Redistributions in binary form must reproduce the above copyright 111849Swollman * notice, this list of conditions and the following disclaimer in the 121849Swollman * documentation and/or other materials provided with the distribution. 131849Swollman * 3. All advertising materials mentioning features or use of this software 141849Swollman * must display the following acknowledgement: 151849Swollman * This product includes software developed by Winning Strategies, Inc. 161849Swollman * 4. The name of the author may not be used to endorse or promote products 171849Swollman * derived from this software without specific prior written permission 181849Swollman * 191849Swollman * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 201849Swollman * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 211849Swollman * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 221849Swollman * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 231849Swollman * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 241849Swollman * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 251849Swollman * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 261849Swollman * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 271849Swollman * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 281849Swollman * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 291849Swollman */ 301849Swollman 3185437Speter#include <machine/asm.h> 3293000Sobrien__FBSDID("$FreeBSD$"); 331849Swollman 341849Swollman/* 351849Swollman * memset(void *b, int c, size_t len) 361849Swollman * write len bytes of value c (converted to an unsigned char) to 371849Swollman * the string b. 381849Swollman * 391849Swollman * Written by: 401849Swollman * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc. 411849Swollman */ 421849Swollman 431849SwollmanENTRY(memset) 441849Swollman pushl %edi 451849Swollman pushl %ebx 461849Swollman movl 12(%esp),%edi 471849Swollman movzbl 16(%esp),%eax /* unsigned char, zero extend */ 481849Swollman movl 20(%esp),%ecx 491849Swollman pushl %edi /* push address of buffer */ 501849Swollman 511849Swollman cld /* set fill direction forward */ 521849Swollman 531849Swollman /* 541849Swollman * if the string is too short, it's really not worth the overhead 551849Swollman * of aligning to word boundries, etc. So we jump to a plain 561849Swollman * unaligned set. 571849Swollman */ 581849Swollman cmpl $0x0f,%ecx 591849Swollman jle L1 601849Swollman 611849Swollman movb %al,%ah /* copy char to all bytes in word */ 621849Swollman movl %eax,%edx 631849Swollman sall $16,%eax 641849Swollman orl %edx,%eax 651849Swollman 661849Swollman movl %edi,%edx /* compute misalignment */ 671849Swollman negl %edx 681849Swollman andl $3,%edx 691849Swollman movl %ecx,%ebx 701849Swollman subl %edx,%ebx 711849Swollman 721849Swollman movl %edx,%ecx /* set until word aligned */ 731849Swollman rep 741849Swollman stosb 751849Swollman 761849Swollman movl %ebx,%ecx 771849Swollman shrl $2,%ecx /* set by words */ 781849Swollman rep 791849Swollman stosl 801849Swollman 811849Swollman movl %ebx,%ecx /* set remainder by bytes */ 821849Swollman andl $3,%ecx 831849SwollmanL1: rep 841849Swollman stosb 851849Swollman 861849Swollman popl %eax /* pop address of buffer */ 871849Swollman popl %ebx 881849Swollman popl %edi 891849Swollman ret 90184548SpeterEND(memset) 91217106Skib 92217106Skib .section .note.GNU-stack,"",%progbits 93