cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

memmove.c (1858B)

      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
     10void *memmove(void *dest, const void *src, size_t n)
     11{
     12	void *xdest = dest;
     13	size_t temp;
     14
     15	if (!n)
     16		return xdest;
     17
     18	if (dest < src) {
     19		if ((long)dest & 1) {
     20			char *cdest = dest;
     21			const char *csrc = src;
     22			*cdest++ = *csrc++;
     23			dest = cdest;
     24			src = csrc;
     25			n--;
     26		}
     27		if (n > 2 && (long)dest & 2) {
     28			short *sdest = dest;
     29			const short *ssrc = src;
     30			*sdest++ = *ssrc++;
     31			dest = sdest;
     32			src = ssrc;
     33			n -= 2;
     34		}
     35		temp = n >> 2;
     36		if (temp) {
     37			long *ldest = dest;
     38			const long *lsrc = src;
     39			temp--;
     40			do
     41				*ldest++ = *lsrc++;
     42			while (temp--);
     43			dest = ldest;
     44			src = lsrc;
     45		}
     46		if (n & 2) {
     47			short *sdest = dest;
     48			const short *ssrc = src;
     49			*sdest++ = *ssrc++;
     50			dest = sdest;
     51			src = ssrc;
     52		}
     53		if (n & 1) {
     54			char *cdest = dest;
     55			const char *csrc = src;
     56			*cdest = *csrc;
     57		}
     58	} else {
     59		dest = (char *)dest + n;
     60		src = (const char *)src + n;
     61		if ((long)dest & 1) {
     62			char *cdest = dest;
     63			const char *csrc = src;
     64			*--cdest = *--csrc;
     65			dest = cdest;
     66			src = csrc;
     67			n--;
     68		}
     69		if (n > 2 && (long)dest & 2) {
     70			short *sdest = dest;
     71			const short *ssrc = src;
     72			*--sdest = *--ssrc;
     73			dest = sdest;
     74			src = ssrc;
     75			n -= 2;
     76		}
     77		temp = n >> 2;
     78		if (temp) {
     79			long *ldest = dest;
     80			const long *lsrc = src;
     81			temp--;
     82			do
     83				*--ldest = *--lsrc;
     84			while (temp--);
     85			dest = ldest;
     86			src = lsrc;
     87		}
     88		if (n & 2) {
     89			short *sdest = dest;
     90			const short *ssrc = src;
     91			*--sdest = *--ssrc;
     92			dest = sdest;
     93			src = ssrc;
     94		}
     95		if (n & 1) {
     96			char *cdest = dest;
     97			const char *csrc = src;
     98			*--cdest = *--csrc;
     99		}
    100	}
    101	return xdest;
    102}
    103EXPORT_SYMBOL(memmove);