1/*- 2 * Copyright (c) 1993 The Regents of the University of California. 3 * Copyright (c) 2003 Peter Wemm. 4 * Copyright (c) 2008 The DragonFly Project. 5 * All rights reserved. 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#include <machine/asm.h> 32 33/* 34 * bcopy(src:%rdi, dst:%rsi, cnt:%rdx) 35 */ 36#ifdef MEMCOPY 37ENTRY(memcpy) 38#else 39#ifdef MEMMOVE 40ENTRY(memmove) 41#else 42ENTRY(bcopy) 43#endif 44#endif 45#if defined(MEMCOPY) || defined(MEMMOVE) 46 movq %rdi,%rax /* return dst */ 47#else 48 xchgq %rdi,%rsi 49#endif 50 movq %rdx,%rcx 51 52 movq %rdi,%r11 53 subq %rsi,%r11 54 cmpq %rcx,%r11 /* overlapping && src < dst? */ 55 jb 2f 56 57 cld /* nope, copy forwards */ 58 shrq $3,%rcx /* copy by 64-bit words */ 59 rep 60 movsq 61 movq %rdx,%rcx 62 andq $7,%rcx /* any bytes left? */ 63 jnz 1f 64 ret 651: rep 66 movsb 67 ret 68 69 .align 4 702: 71 addq %rcx,%rdi /* copy backwards */ 72 addq %rcx,%rsi 73 std 74 decq %rdi 75 decq %rsi 76 andq $7,%rcx /* any fractional bytes? */ 77 jz 3f 78 rep 79 movsb 803: movq %rdx,%rcx /* copy by 32-bit words */ 81 shrq $3,%rcx 82 subq $7,%rsi 83 subq $7,%rdi 84 rep 85 movsq 86 cld 87 ret 88#ifdef MEMCOPY 89END(memcpy) 90#else 91#ifdef MEMMOVE 92END(memmove) 93#else 94END(bcopy) 95#endif 96#endif 97 98 .section .note.GNU-stack,"",%progbits 99