Viewing file:  memcpy.c (1.44 KB) -rw-r--r--
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#include <linux/types.h>
void * memcpy(void * to, const void * from, size_t n)
{
void *xto = to;
size_t temp, temp1;
if (!n)
return xto;
if ((long) to & 1)
{
char *cto = to;
const char *cfrom = from;
*cto++ = *cfrom++;
to = cto;
from = cfrom;
n--;
}
if (n > 2 && (long) to & 2)
{
short *sto = to;
const short *sfrom = from;
*sto++ = *sfrom++;
to = sto;
from = sfrom;
n -= 2;
}
temp = n >> 2;
if (temp)
{
long *lto = to;
const long *lfrom = from;
__asm__ __volatile__("movel %2,%3\n\t"
"andw #7,%3\n\t"
"lsrl #3,%2\n\t"
"negw %3\n\t"
"jmp %%pc@(1f,%3:w:2)\n\t"
"4:\t"
"movel %0@+,%1@+\n\t"
"movel %0@+,%1@+\n\t"
"movel %0@+,%1@+\n\t"
"movel %0@+,%1@+\n\t"
"movel %0@+,%1@+\n\t"
"movel %0@+,%1@+\n\t"
"movel %0@+,%1@+\n\t"
"movel %0@+,%1@+\n\t"
"1:\t"
"dbra %2,4b\n\t"
"clrw %2\n\t"
"subql #1,%2\n\t"
"jpl 4b\n\t"
: "=a" (lfrom), "=a" (lto), "=d" (temp),
"=&d" (temp1)
: "0" (lfrom), "1" (lto), "2" (temp)
);
to = lto;
from = lfrom;
}
if (n & 2)
{
short *sto = to;
const short *sfrom = from;
*sto++ = *sfrom++;
to = sto;
from = sfrom;
}
if (n & 1)
{
char *cto = to;
const char *cfrom = from;
*cto = *cfrom;
}
return xto;
}
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