memset.c
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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <linux/string.h>
void *memset(void *s, int c, size_t count)
{
void *xs = s;
size_t temp;
if (!count)
return xs;
c &= 0xff;
c |= c << 8;
c |= c << 16;
if ((long)s & 1) {
char *cs = s;
*cs++ = c;
s = cs;
count--;
}
if (count > 2 && (long)s & 2) {
short *ss = s;
*ss++ = c;
s = ss;
count -= 2;
}
temp = count >> 2;
if (temp) {
long *ls = s;
#if defined(CONFIG_M68000) || defined(CONFIG_COLDFIRE)
for (; temp; temp--)
*ls++ = c;
#else
size_t temp1;
asm volatile (
" movel %1,%2\n"
" andw #7,%2\n"
" lsrl #3,%1\n"
" negw %2\n"
" jmp %%pc@(2f,%2:w:2)\n"
"1: movel %3,%0@+\n"
" movel %3,%0@+\n"
" movel %3,%0@+\n"
" movel %3,%0@+\n"
" movel %3,%0@+\n"
" movel %3,%0@+\n"
" movel %3,%0@+\n"
" movel %3,%0@+\n"
"2: dbra %1,1b\n"
" clrw %1\n"
" subql #1,%1\n"
" jpl 1b"
: "=a" (ls), "=d" (temp), "=&d" (temp1)
: "d" (c), "0" (ls), "1" (temp));
#endif
s = ls;
}
if (count & 2) {
short *ss = s;
*ss++ = c;
s = ss;
}
if (count & 1) {
char *cs = s;
*cs = c;
}
return xs;
}
EXPORT_SYMBOL(memset);