mirror of https://gitee.com/openkylin/linux.git
90 lines
1.7 KiB
C
90 lines
1.7 KiB
C
/*
|
|
* 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 *memcpy(void *to, const void *from, size_t n)
|
|
{
|
|
void *xto = to;
|
|
size_t temp;
|
|
|
|
if (!n)
|
|
return xto;
|
|
if ((long)to & 1) {
|
|
char *cto = to;
|
|
const char *cfrom = from;
|
|
*cto++ = *cfrom++;
|
|
to = cto;
|
|
from = cfrom;
|
|
n--;
|
|
}
|
|
#if defined(CONFIG_M68000)
|
|
if ((long)from & 1) {
|
|
char *cto = to;
|
|
const char *cfrom = from;
|
|
for (; n; n--)
|
|
*cto++ = *cfrom++;
|
|
return xto;
|
|
}
|
|
#endif
|
|
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;
|
|
#if defined(CONFIG_M68000) || defined(CONFIG_COLDFIRE)
|
|
for (; temp; temp--)
|
|
*lto++ = *lfrom++;
|
|
#else
|
|
size_t temp1;
|
|
asm volatile (
|
|
" movel %2,%3\n"
|
|
" andw #7,%3\n"
|
|
" lsrl #3,%2\n"
|
|
" negw %3\n"
|
|
" jmp %%pc@(1f,%3:w:2)\n"
|
|
"4: movel %0@+,%1@+\n"
|
|
" movel %0@+,%1@+\n"
|
|
" movel %0@+,%1@+\n"
|
|
" movel %0@+,%1@+\n"
|
|
" movel %0@+,%1@+\n"
|
|
" movel %0@+,%1@+\n"
|
|
" movel %0@+,%1@+\n"
|
|
" movel %0@+,%1@+\n"
|
|
"1: dbra %2,4b\n"
|
|
" clrw %2\n"
|
|
" subql #1,%2\n"
|
|
" jpl 4b"
|
|
: "=a" (lfrom), "=a" (lto), "=d" (temp), "=&d" (temp1)
|
|
: "0" (lfrom), "1" (lto), "2" (temp));
|
|
#endif
|
|
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;
|
|
}
|
|
EXPORT_SYMBOL(memcpy);
|