1/*- 2 * Copyright (c) 1990 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from locore.s. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * $NetBSD: bcopy.S,v 1.2 2003/08/07 16:42:36 agc Exp $ 32 * $FreeBSD: src/lib/libc/amd64/string/bcopy.S,v 1.3 2008/11/02 01:10:54 peter Exp $ 33 */ 34 35#include <machine/asm.h> 36 37 /* 38 * (ov)bcopy (src,dst,cnt) 39 * ws@tools.de (Wolfgang Solfrank, TooLs GmbH) +49-228-985800 40 */ 41 42#ifdef MEMCOPY 43ENTRY(memcpy) 44#else 45#ifdef MEMMOVE 46ENTRY(memmove) 47#else 48ENTRY(bcopy) 49#endif 50#endif 51#if defined(MEMCOPY) || defined(MEMMOVE) 52 movq %rdi,%rax /* return dst */ 53#else 54 xchgq %rdi,%rsi 55#endif 56 movq %rdx,%rcx 57 movq %rdi,%r8 58 subq %rsi,%r8 59 cmpq %rcx,%r8 /* overlapping? */ 60 jb 1f 61 cld /* nope, copy forwards. */ 62 shrq $3,%rcx /* copy by words */ 63 rep 64 movsq 65 movq %rdx,%rcx 66 andq $7,%rcx /* any bytes left? */ 67 rep 68 movsb 69 ret 701: 71 addq %rcx,%rdi /* copy backwards. */ 72 addq %rcx,%rsi 73 std 74 andq $7,%rcx /* any fractional bytes? */ 75 decq %rdi 76 decq %rsi 77 rep 78 movsb 79 movq %rdx,%rcx /* copy remainder by words */ 80 shrq $3,%rcx 81 subq $7,%rsi 82 subq $7,%rdi 83 rep 84 movsq 85 cld 86 ret 87#ifdef MEMCOPY 88END(memcpy) 89#else 90#ifdef MEMMOVE 91END(memmove) 92#else 93END(bcopy) 94#endif 95#endif 96