bcopy.S revision 1.1
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 * $Id: bcopy.S,v 1.1 1993/10/07 00:19:21 cgd Exp $ 36 1.1 cgd */ 37 1.1 cgd 38 1.1 cgd #if defined(LIBC_RCS) && !defined(lint) 39 1.1 cgd .text 40 1.1 cgd .asciz "$Id: bcopy.S,v 1.1 1993/10/07 00:19:21 cgd Exp $" 41 1.1 cgd #endif /* LIBC_RCS and not lint */ 42 1.1 cgd 43 1.1 cgd #include "DEFS.h" 44 1.1 cgd 45 1.1 cgd /* 46 1.1 cgd * (ov)bcopy (src,dst,cnt) 47 1.1 cgd * ws (at) tools.de (Wolfgang Solfrank, TooLs GmbH) +49-228-985800 48 1.1 cgd */ 49 1.1 cgd 50 1.1 cgd ENTRY(bcopy) 51 1.1 cgd pushl %esi 52 1.1 cgd pushl %edi 53 1.1 cgd movl 12(%esp),%esi 54 1.1 cgd movl 16(%esp),%edi 55 1.1 cgd movl 20(%esp),%ecx 56 1.1 cgd cmpl %esi,%edi /* potentially overlapping? */ 57 1.1 cgd jnb 1f 58 1.1 cgd cld /* nope, copy forwards. */ 59 1.1 cgd shrl $2,%ecx /* copy by words */ 60 1.1 cgd rep 61 1.1 cgd movsl 62 1.1 cgd movl 20(%esp),%ecx 63 1.1 cgd andl $3,%ecx /* any bytes left? */ 64 1.1 cgd rep 65 1.1 cgd movsb 66 1.1 cgd popl %edi 67 1.1 cgd popl %esi 68 1.1 cgd ret 69 1.1 cgd 1: 70 1.1 cgd addl %ecx,%edi /* copy backwards. */ 71 1.1 cgd addl %ecx,%esi 72 1.1 cgd std 73 1.1 cgd andl $3,%ecx /* any fractional bytes? */ 74 1.1 cgd decl %edi 75 1.1 cgd decl %esi 76 1.1 cgd rep 77 1.1 cgd movsb 78 1.1 cgd movl 20(%esp),%ecx /* copy remainder by words */ 79 1.1 cgd shrl $2,%ecx 80 1.1 cgd subl $3,%esi 81 1.1 cgd subl $3,%edi 82 1.1 cgd rep 83 1.1 cgd movsl 84 1.1 cgd popl %edi 85 1.1 cgd popl %esi 86 1.1 cgd cld 87 1.1 cgd ret 88
Indexes created Wed Sep 24 05:09:52 GMT 2025