/* $OpenBSD: bcopy.S,v 1.5 2005/08/07 11:30:38 espie Exp $ */ /*- * Copyright (c) 1990 The Regents of the University of California. * All rights reserved. * * This code is derived from locore.s. * * 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. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS 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 /* * (ov)bcopy (src,dst,cnt) * ws@tools.de (Wolfgang Solfrank, TooLs GmbH) +49-228-985800 */ #ifdef MEMCOPY ENTRY(memcpy) #else #ifdef MEMMOVE ENTRY(memmove) #else ENTRY(bcopy) #endif #endif pushl %esi pushl %edi #if defined(MEMCOPY) || defined(MEMMOVE) movl 12(%esp),%edi movl 16(%esp),%esi movl %edi, %eax #else movl 12(%esp),%esi movl 16(%esp),%edi #endif movl 20(%esp),%ecx movl %ecx,%edx cmpl %esi,%edi /* potentially overlapping? */ jnb 1f cld /* nope, copy forwards. */ shrl $2,%ecx /* copy by words */ rep movsl movl %edx,%ecx andl $3,%ecx /* any bytes left? */ rep movsb popl %edi popl %esi ret 1: addl %ecx,%edi /* copy backwards. */ addl %ecx,%esi std andl $3,%ecx /* any fractional bytes? */ decl %edi decl %esi rep movsb movl %edx,%ecx shrl $2,%ecx subl $3,%esi subl $3,%edi rep movsl popl %edi popl %esi cld ret