kernel_optimize_test/arch/m68k/lib/memset.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

69 lines
1.2 KiB
C

#include <linux/types.h>
void * memset(void * s, int c, size_t count)
{
void *xs = s;
size_t temp, temp1;
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;
__asm__ __volatile__("movel %1,%2\n\t"
"andw #7,%2\n\t"
"lsrl #3,%1\n\t"
"negw %2\n\t"
"jmp %%pc@(2f,%2:w:2)\n\t"
"1:\t"
"movel %3,%0@+\n\t"
"movel %3,%0@+\n\t"
"movel %3,%0@+\n\t"
"movel %3,%0@+\n\t"
"movel %3,%0@+\n\t"
"movel %3,%0@+\n\t"
"movel %3,%0@+\n\t"
"movel %3,%0@+\n\t"
"2:\t"
"dbra %1,1b\n\t"
"clrw %1\n\t"
"subql #1,%1\n\t"
"jpl 1b\n\t"
: "=a" (ls), "=d" (temp), "=&d" (temp1)
: "d" (c), "0" (ls), "1" (temp)
);
s = ls;
}
if (count & 2)
{
short *ss = s;
*ss++ = c;
s = ss;
}
if (count & 1)
{
char *cs = s;
*cs = c;
}
return xs;
}