xref: /linux/arch/m68k/lib/memset.c (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file COPYING in the main directory of this archive
4  * for more details.
5  */
6 
7 #include <linux/module.h>
8 #include <linux/string.h>
9 
10 void *memset(void *s, int c, size_t count)
11 {
12 	void *xs = s;
13 	size_t temp;
14 
15 	if (!count)
16 		return xs;
17 	c &= 0xff;
18 	c |= c << 8;
19 	c |= c << 16;
20 	if ((long)s & 1) {
21 		char *cs = s;
22 		*cs++ = c;
23 		s = cs;
24 		count--;
25 	}
26 	if (count > 2 && (long)s & 2) {
27 		short *ss = s;
28 		*ss++ = c;
29 		s = ss;
30 		count -= 2;
31 	}
32 	temp = count >> 2;
33 	if (temp) {
34 		long *ls = s;
35 #if defined(CONFIG_M68000) || defined(CONFIG_COLDFIRE)
36 		for (; temp; temp--)
37 			*ls++ = c;
38 #else
39 		size_t temp1;
40 		asm volatile (
41 			"	movel %1,%2\n"
42 			"	andw  #7,%2\n"
43 			"	lsrl  #3,%1\n"
44 			"	negw  %2\n"
45 			"	jmp   %%pc@(2f,%2:w:2)\n"
46 			"1:	movel %3,%0@+\n"
47 			"	movel %3,%0@+\n"
48 			"	movel %3,%0@+\n"
49 			"	movel %3,%0@+\n"
50 			"	movel %3,%0@+\n"
51 			"	movel %3,%0@+\n"
52 			"	movel %3,%0@+\n"
53 			"	movel %3,%0@+\n"
54 			"2:	dbra  %1,1b\n"
55 			"	clrw  %1\n"
56 			"	subql #1,%1\n"
57 			"	jpl   1b"
58 			: "=a" (ls), "=d" (temp), "=&d" (temp1)
59 			: "d" (c), "0" (ls), "1" (temp));
60 #endif
61 		s = ls;
62 	}
63 	if (count & 2) {
64 		short *ss = s;
65 		*ss++ = c;
66 		s = ss;
67 	}
68 	if (count & 1) {
69 		char *cs = s;
70 		*cs = c;
71 	}
72 	return xs;
73 }
74 EXPORT_SYMBOL(memset);
75