1/*
2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*
29 * @OSF_COPYRIGHT@
30 */
31/*
32 * Mach Operating System
33 * Copyright (c) 1991,1990 Carnegie Mellon University
34 * All Rights Reserved.
35 *
36 * Permission to use, copy, modify and distribute this software and its
37 * documentation is hereby granted, provided that both the copyright
38 * notice and this permission notice appear in all copies of the
39 * software, derivative works or modified versions, and any portions
40 * thereof, and that both notices appear in supporting documentation.
41 *
42 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
43 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
44 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
45 *
46 * Carnegie Mellon requests users of this software to return to
47 *
48 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
49 *  School of Computer Science
50 *  Carnegie Mellon University
51 *  Pittsburgh PA 15213-3890
52 *
53 * any improvements or extensions that they make and grant Carnegie Mellon
54 * the rights to redistribute these changes.
55 */
56/*
57 */
58
59#include <i386/asm.h>
60
61/* void *memcpy((void *) to, (const void *) from, (size_t) bcount) */
62/*			rdi,	 	     rsi,	      rdx   */
63/*
64 * Note: memcpy does not support overlapping copies
65 */
66ENTRY(memcpy)
67	movq	%rdx,%rcx
68	shrq	$3,%rcx				/* copy by 64-bit words */
69	cld					/* copy forwards */
70	rep
71	movsq
72	movq	%rdx,%rcx
73	andq	$7,%rcx				/* any bytes left? */
74	rep
75	movsb
76	ret
77
78/* void bcopy((const char *) from, (char *) to, (unsigned int) count) */
79/*			      rdi, 	   rsi,			 rdx  */
80
81ENTRY(bcopy_no_overwrite)
82	xchgq	%rsi,%rdi
83	jmp	EXT(memcpy)
84
85/*
86 * bcopy(src, dst, cnt)
87 *       rdi, rsi, rdx
88 *  ws@tools.de     (Wolfgang Solfrank, TooLs GmbH) +49-228-985800
89 */
90ENTRY(bcopy)
91	xchgq	%rsi,%rdi
92	movq	%rdx,%rcx
93
94	movq	%rdi,%rax
95	subq	%rsi,%rax
96	cmpq	%rcx,%rax			/* overlapping && src < dst? */
97	jb	1f
98
99	shrq	$3,%rcx				/* copy by 64-bit words */
100	cld					/* nope, copy forwards */
101	rep
102	movsq
103	movq	%rdx,%rcx
104	andq	$7,%rcx				/* any bytes left? */
105	rep
106	movsb
107	ret
108
109	/* ALIGN_TEXT */
1101:
111	addq	%rcx,%rdi			/* copy backwards */
112	addq	%rcx,%rsi
113	decq	%rdi
114	decq	%rsi
115	andq	$7,%rcx				/* any fractional bytes? */
116	std
117	rep
118	movsb
119	movq	%rdx,%rcx			/* copy remainder by 32-bit words */
120	shrq	$3,%rcx
121	subq	$7,%rsi
122	subq	$7,%rdi
123	rep
124	movsq
125	cld
126	ret
127