bcopy.S revision 1.7
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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <machine/asm.h> 37 38 #if defined(LIBC_SCCS) 39 RCSID("$NetBSD: bcopy.S,v 1.7 2002/07/04 15:48:40 kent Exp $") 40 #endif 41 42 /* 43 * (ov)bcopy (src,dst,cnt) 44 * ws (at) tools.de (Wolfgang Solfrank, TooLs GmbH) +49-228-985800 45 */ 46 47 #ifdef MEMCOPY 48 ENTRY(memcpy) 49 #else 50 #ifdef MEMMOVE 51 ENTRY(memmove) 52 #else 53 ENTRY(bcopy) 54 #endif 55 #endif 56 pushl %esi 57 pushl %edi 58 #if defined(MEMCOPY) || defined(MEMMOVE) 59 movl 12(%esp),%edi 60 movl 16(%esp),%esi 61 #else 62 movl 12(%esp),%esi 63 movl 16(%esp),%edi 64 #endif 65 movl 20(%esp),%ecx 66 movl %edi,%eax 67 subl %esi,%eax 68 cmpl %ecx,%eax /* overlapping? */ 69 jb 1f 70 cld /* nope, copy forwards. */ 71 shrl $2,%ecx /* copy by words */ 72 rep 73 movsl 74 movl 20(%esp),%ecx 75 andl $3,%ecx /* any bytes left? */ 76 rep 77 movsb 78 #if defined(MEMCOPY) || defined(MEMMOVE) 79 movl 12(%esp),%eax 80 #endif 81 popl %edi 82 popl %esi 83 ret 84 1: 85 addl %ecx,%edi /* copy backwards. */ 86 addl %ecx,%esi 87 #ifdef _DIAGNOSTIC 88 #define _DIAGASSERT call _C_LABEL(__diagassert13) 89 cmpl 12(%esp),%edi /* check pointer wraparound */ 90 jae 2f 91 pushl $diagmes1 92 pushl $func 93 pushl $__LINE__-4 94 pushl $file 95 _DIAGASSERT 96 addl $16,%esp 97 jmp 4f 98 2: 99 cmpl 16(%esp),%esi 100 jae 3f 101 pushl $diagmes2 102 pushl $func 103 pushl $__LINE__-4 104 pushl $file 105 _DIAGASSERT 106 addl $16,%esp 107 jmp 4f 108 3: 109 #endif 110 std 111 andl $3,%ecx /* any fractional bytes? */ 112 decl %edi 113 decl %esi 114 rep 115 movsb 116 movl 20(%esp),%ecx /* copy remainder by words */ 117 shrl $2,%ecx 118 subl $3,%esi 119 subl $3,%edi 120 rep 121 movsl 122 4: 123 #if defined(MEMCOPY) || defined(MEMMOVE) 124 movl 12(%esp),%eax 125 #endif 126 popl %edi 127 popl %esi 128 cld 129 ret 130 131 #ifdef _DIAGNOSTIC 132 file: 133 .asciz __FILE__ 134 func: 135 #if defined(MEMCOPY) 136 .asciz "memcpy" 137 #elseif defined(MEMMOVE) 138 .asciz "memmove" 139 #else 140 .asciz "bcopy" 141 #endif 142 diagmes1: 143 .asciz "src + length > src" 144 diagmes2: 145 .asciz "dst + length > dst" 146 #endif /* _DIAGNOSTIC */ 147
Indexes created Mon Sep 29 15:09:53 GMT 2025