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1c79356b
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1/*
2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3 *
2d21ac55 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b 5 *
2d21ac55
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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.
8f6c56a5 14 *
2d21ac55
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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
8f6c56a5
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20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55
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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.
8f6c56a5 25 *
2d21ac55 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b 27 */
b0d623f7 28 /*
1c79356b
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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
b0d623f7
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59#include <i386/asm.h>
60
1c79356b 61/*
b0d623f7 62 * void *memset(void * addr, int pattern, size_t length)
1c79356b 63 */
1c79356b 64
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65ENTRY(memset)
66 movq %rdi, %r8
67 movq %rsi, %rax /* move pattern (arg2) to rax */
68 movb %al,%ah /* fill out pattern */
69 movw %ax,%cx
70 shll $16,%eax
71 movw %cx,%ax
72 mov %eax, %ecx
73 shlq $32,%rax
74 orq %rcx, %rax
75 cld /* reset direction flag */
76 movq %rdx, %rcx /* mov quads first */
77 shrq $3, %rcx
78 rep
79 stosq
80 movq %rdx,%rcx /* mov bytes */
81 andq $7,%rcx
82 rep
83 stosb
84 movq %r8 ,%rax /* returns its first argument */
85 ret
1c79356b 86
b0d623f7
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87/*
88 * void bzero(char * addr, size_t length)
89 */
90Entry(blkclr)
91ENTRY(bzero)
92 movq %rsi,%rcx
93 xorq %rax,%rax
94 shrq $3,%rcx
95 cld
96 rep
97 stosq
98 movq %rsi,%rcx
99 andq $7,%rcx
100 rep
101 stosb
102 ret