Commit 982cd252 authored by Greg Ungerer's avatar Greg Ungerer
Browse files

m68knommu: add optimize memmove() function 



Add an m68k/coldfire optimized memmove() function for the m68knommu arch.
This is the same function as used by m68k. Simple speed tests show this
is faster once buffers are larger than 4 bytes, and significantly faster
on much larger buffers (4 times faster above about 100 bytes).

This also goes part of the way to fixing a regression caused by commit
ea61bc46 ("m68k/m68knommu: merge MMU and
non-MMU string.h"), which breaks non-coldfire non-mmu builds (which is
the 68x328 and 68360 families). They currently have no memmove() fucntion
defined, since there was none in the m68knommu/lib functions.

Signed-off-by: default avatarGreg Ungerer <gerg@uclinux.org>
parent f9d693d2

arch/m68k/include/asm/string.h

+1 −1
Original line number Diff line number Diff line
@@ -99,10 +99,10 @@ static inline int strcmp(const char *cs, const char *ct) 
		: "+a" (cs), "+a" (ct), "=d" (res));

	return res;

}

#endif /* CONFIG_COLDFIRE */



#define __HAVE_ARCH_MEMMOVE

extern void *memmove(void *, const void *, __kernel_size_t);

#endif /* CONFIG_COLDFIRE */



#define memcmp(d, s, n) __builtin_memcmp(d, s, n)

arch/m68knommu/lib/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -4,4 +4,4 @@ 


lib-y	:= ashldi3.o ashrdi3.o lshrdi3.o \

	   muldi3.o mulsi3.o divsi3.o udivsi3.o modsi3.o umodsi3.o \

	   checksum.o memcpy.o memset.o delay.o
 
	   checksum.o memcpy.o memmove.o memset.o delay.o

arch/m68knommu/lib/memmove.c

0 → 100644
+105 −0
Original line number Diff line number Diff line 
/*

 * 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.

 */



#define __IN_STRING_C



#include <linux/module.h>

#include <linux/string.h>



void *memmove(void *dest, const void *src, size_t n)

{

	void *xdest = dest;

	size_t temp;



	if (!n)

		return xdest;



	if (dest < src) {

		if ((long)dest & 1) {

			char *cdest = dest;

			const char *csrc = src;

			*cdest++ = *csrc++;

			dest = cdest;

			src = csrc;

			n--;

		}

		if (n > 2 && (long)dest & 2) {

			short *sdest = dest;

			const short *ssrc = src;

			*sdest++ = *ssrc++;

			dest = sdest;

			src = ssrc;

			n -= 2;

		}

		temp = n >> 2;

		if (temp) {

			long *ldest = dest;

			const long *lsrc = src;

			temp--;

			do

				*ldest++ = *lsrc++;

			while (temp--);

			dest = ldest;

			src = lsrc;

		}

		if (n & 2) {

			short *sdest = dest;

			const short *ssrc = src;

			*sdest++ = *ssrc++;

			dest = sdest;

			src = ssrc;

		}

		if (n & 1) {

			char *cdest = dest;

			const char *csrc = src;

			*cdest = *csrc;

		}

	} else {

		dest = (char *)dest + n;

		src = (const char *)src + n;

		if ((long)dest & 1) {

			char *cdest = dest;

			const char *csrc = src;

			*--cdest = *--csrc;

			dest = cdest;

			src = csrc;

			n--;

		}

		if (n > 2 && (long)dest & 2) {

			short *sdest = dest;

			const short *ssrc = src;

			*--sdest = *--ssrc;

			dest = sdest;

			src = ssrc;

			n -= 2;

		}

		temp = n >> 2;

		if (temp) {

			long *ldest = dest;

			const long *lsrc = src;

			temp--;

			do

				*--ldest = *--lsrc;

			while (temp--);

			dest = ldest;

			src = lsrc;

		}

		if (n & 2) {

			short *sdest = dest;

			const short *ssrc = src;

			*--sdest = *--ssrc;

			dest = sdest;

			src = ssrc;

		}

		if (n & 1) {

			char *cdest = dest;

			const char *csrc = src;

			*--cdest = *--csrc;

		}

	}

	return xdest;

}

EXPORT_SYMBOL(memmove);

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