1/*
2 * Copyright (c) 1993 Winning Strategies, Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by Winning Strategies, Inc.
16 * 4. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include <machine/asm.h>
| 1/*
2 * Copyright (c) 1993 Winning Strategies, Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by Winning Strategies, Inc.
16 * 4. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include <machine/asm.h>
|
32__FBSDID("$FreeBSD: head/lib/libc/i386/string/memset.S 93000 2002-03-23 02:44:19Z obrien $");
| 32__FBSDID("$FreeBSD: head/lib/libc/i386/string/memset.S 184548 2008-11-02 01:28:47Z peter $");
|
33
34/*
35 * memset(void *b, int c, size_t len)
36 * write len bytes of value c (converted to an unsigned char) to
37 * the string b.
38 *
39 * Written by:
40 * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc.
41 */
42
43ENTRY(memset)
44 pushl %edi
45 pushl %ebx
46 movl 12(%esp),%edi
47 movzbl 16(%esp),%eax /* unsigned char, zero extend */
48 movl 20(%esp),%ecx
49 pushl %edi /* push address of buffer */
50
51 cld /* set fill direction forward */
52
53 /*
54 * if the string is too short, it's really not worth the overhead
55 * of aligning to word boundries, etc. So we jump to a plain
56 * unaligned set.
57 */
58 cmpl $0x0f,%ecx
59 jle L1
60
61 movb %al,%ah /* copy char to all bytes in word */
62 movl %eax,%edx
63 sall $16,%eax
64 orl %edx,%eax
65
66 movl %edi,%edx /* compute misalignment */
67 negl %edx
68 andl $3,%edx
69 movl %ecx,%ebx
70 subl %edx,%ebx
71
72 movl %edx,%ecx /* set until word aligned */
73 rep
74 stosb
75
76 movl %ebx,%ecx
77 shrl $2,%ecx /* set by words */
78 rep
79 stosl
80
81 movl %ebx,%ecx /* set remainder by bytes */
82 andl $3,%ecx
83L1: rep
84 stosb
85
86 popl %eax /* pop address of buffer */
87 popl %ebx
88 popl %edi
89 ret
| 33
34/*
35 * memset(void *b, int c, size_t len)
36 * write len bytes of value c (converted to an unsigned char) to
37 * the string b.
38 *
39 * Written by:
40 * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc.
41 */
42
43ENTRY(memset)
44 pushl %edi
45 pushl %ebx
46 movl 12(%esp),%edi
47 movzbl 16(%esp),%eax /* unsigned char, zero extend */
48 movl 20(%esp),%ecx
49 pushl %edi /* push address of buffer */
50
51 cld /* set fill direction forward */
52
53 /*
54 * if the string is too short, it's really not worth the overhead
55 * of aligning to word boundries, etc. So we jump to a plain
56 * unaligned set.
57 */
58 cmpl $0x0f,%ecx
59 jle L1
60
61 movb %al,%ah /* copy char to all bytes in word */
62 movl %eax,%edx
63 sall $16,%eax
64 orl %edx,%eax
65
66 movl %edi,%edx /* compute misalignment */
67 negl %edx
68 andl $3,%edx
69 movl %ecx,%ebx
70 subl %edx,%ebx
71
72 movl %edx,%ecx /* set until word aligned */
73 rep
74 stosb
75
76 movl %ebx,%ecx
77 shrl $2,%ecx /* set by words */
78 rep
79 stosl
80
81 movl %ebx,%ecx /* set remainder by bytes */
82 andl $3,%ecx
83L1: rep
84 stosb
85
86 popl %eax /* pop address of buffer */
87 popl %ebx
88 popl %edi
89 ret
|
| 90END(memset)
|
| |