bcopy.S revision 1.9
1 1.1 cgd /*- 2 1.1 cgd * Copyright (c) 1990 The Regents of the University of California. 3 1.1 cgd * All rights reserved. 4 1.1 cgd * 5 1.1 cgd * This code is derived from locore.s. 6 1.1 cgd * 7 1.1 cgd * Redistribution and use in source and binary forms, with or without 8 1.1 cgd * modification, are permitted provided that the following conditions 9 1.1 cgd * are met: 10 1.1 cgd * 1. Redistributions of source code must retain the above copyright 11 1.1 cgd * notice, this list of conditions and the following disclaimer. 12 1.1 cgd * 2. Redistributions in binary form must reproduce the above copyright 13 1.1 cgd * notice, this list of conditions and the following disclaimer in the 14 1.1 cgd * documentation and/or other materials provided with the distribution. 15 1.1 cgd * 3. All advertising materials mentioning features or use of this software 16 1.1 cgd * must display the following acknowledgement: 17 1.1 cgd * This product includes software developed by the University of 18 1.1 cgd * California, Berkeley and its contributors. 19 1.1 cgd * 4. Neither the name of the University nor the names of its contributors 20 1.1 cgd * may be used to endorse or promote products derived from this software 21 1.1 cgd * without specific prior written permission. 22 1.1 cgd * 23 1.1 cgd * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 1.1 cgd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 1.1 cgd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 1.1 cgd * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 1.1 cgd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 1.1 cgd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 1.1 cgd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 1.1 cgd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 1.1 cgd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 1.1 cgd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 1.1 cgd * SUCH DAMAGE. 34 1.1 cgd */ 35 1.1 cgd 36 1.4 jtc #include <machine/asm.h> 37 1.4 jtc 38 1.2 jtc #if defined(LIBC_SCCS) 39 1.9 junyoung RCSID("$NetBSD: bcopy.S,v 1.9 2002/10/29 06:35:17 junyoung Exp $") 40 1.2 jtc #endif 41 1.1 cgd 42 1.1 cgd /* 43 1.1 cgd * (ov)bcopy (src,dst,cnt) 44 1.1 cgd * ws (at) tools.de (Wolfgang Solfrank, TooLs GmbH) +49-228-985800 45 1.1 cgd */ 46 1.1 cgd 47 1.3 mycroft #ifdef MEMCOPY 48 1.3 mycroft ENTRY(memcpy) 49 1.3 mycroft #else 50 1.3 mycroft #ifdef MEMMOVE 51 1.3 mycroft ENTRY(memmove) 52 1.3 mycroft #else 53 1.1 cgd ENTRY(bcopy) 54 1.3 mycroft #endif 55 1.3 mycroft #endif 56 1.1 cgd pushl %esi 57 1.1 cgd pushl %edi 58 1.3 mycroft #if defined(MEMCOPY) || defined(MEMMOVE) 59 1.3 mycroft movl 12(%esp),%edi 60 1.3 mycroft movl 16(%esp),%esi 61 1.8 kent movl %edi,%eax /* return value */ 62 1.3 mycroft #else 63 1.1 cgd movl 12(%esp),%esi 64 1.1 cgd movl 16(%esp),%edi 65 1.3 mycroft #endif 66 1.1 cgd movl 20(%esp),%ecx 67 1.8 kent movl %edi,%edx 68 1.8 kent subl %esi,%edx 69 1.8 kent cmpl %ecx,%edx /* overlapping? */ 70 1.8 kent movl %ecx,%edx 71 1.6 jtc jb 1f 72 1.1 cgd cld /* nope, copy forwards. */ 73 1.1 cgd shrl $2,%ecx /* copy by words */ 74 1.1 cgd rep 75 1.1 cgd movsl 76 1.8 kent movl %edx,%ecx 77 1.1 cgd andl $3,%ecx /* any bytes left? */ 78 1.1 cgd rep 79 1.1 cgd movsb 80 1.1 cgd popl %edi 81 1.1 cgd popl %esi 82 1.1 cgd ret 83 1.1 cgd 1: 84 1.1 cgd addl %ecx,%edi /* copy backwards. */ 85 1.1 cgd addl %ecx,%esi 86 1.1 cgd std 87 1.1 cgd andl $3,%ecx /* any fractional bytes? */ 88 1.1 cgd decl %edi 89 1.1 cgd decl %esi 90 1.1 cgd rep 91 1.1 cgd movsb 92 1.8 kent movl %edx,%ecx /* copy remainder by words */ 93 1.1 cgd shrl $2,%ecx 94 1.1 cgd subl $3,%esi 95 1.1 cgd subl $3,%edi 96 1.1 cgd rep 97 1.1 cgd movsl 98 1.1 cgd popl %edi 99 1.1 cgd popl %esi 100 1.1 cgd cld 101 1.1 cgd ret 102
Indexes created Mon Sep 29 21:09:56 GMT 2025