memcpy.s

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/* Copy SIZE bytes from SRC to DEST.  For SUN4V Niagara.
   Copyright (C) 2006 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by David S. Miller ([e-mail])

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <sysdep.h>

#define ASI_BLK_INIT_QUAD_LDD_P	0xe2
#define ASI_P			0x80
#define ASI_PNF			0x82

#define LOAD(type,addr,dest)	type##a [addr] ASI_P, dest
#define LOAD_TWIN(addr_reg,dest0,dest1)	\
	ldda [addr_reg] ASI_BLK_INIT_QUAD_LDD_P, dest0

#define STORE(type,src,addr)	type src, [addr]
#define STORE_INIT(src,addr)	stxa src, [addr] %asi

#ifndef XCC
#define USE_BPR
#define XCC xcc
#endif

	.register	%g2,#scratch
	.register	%g3,#scratch
	.register	%g6,#scratch

	.text
	.align		32

ENTRY(bcopy)
	sub		%o1, %o0, %o4
	mov		%o0, %g4
	cmp		%o4, %o2
	mov		%o1, %o0
	bgeu,pt		%XCC, 100f
	 mov		%g4, %o1
#ifndef USE_BPR
	srl		%o2, 0, %o2
#endif
	brnz,pn		%o2, 220f
	 add		%o0, %o2, %o0
	retl
	 nop
END(bcopy)

	.align		32
ENTRY(memcpy)
100:	/* %o0=dst, %o1=src, %o2=len */
	mov		%o0, %g5
	cmp		%o2, 0
	be,pn		%XCC, 85f
218:	 or		%o0, %o1, %o3
	cmp		%o2, 16
	blu,a,pn	%XCC, 80f
	 or		%o3, %o2, %o3

	/* 2 blocks (128 bytes) is the minimum we can do the block
	 * copy with.  We need to ensure that we'll iterate at least
	 * once in the block copy loop.  At worst we'll need to align
	 * the destination to a 64-byte boundary which can chew up
	 * to (64 - 1) bytes from the length before we perform the
	 * block copy loop.
	 */
	cmp		%o2, (2 * 64)
	blu,pt		%XCC, 70f
	 andcc		%o3, 0x7, %g0

	/* %o0:	dst
	 * %o1:	src
	 * %o2:	len  (known to be >= 128)
	 *
	 * The block copy loops will use %o4/%o5,%g2/%g3 as
	 * temporaries while copying the data.
	 */

	LOAD(prefetch, %o1, #one_read)
	wr		%g0, ASI_BLK_INIT_QUAD_LDD_P, %asi

	/* Align destination on 64-byte boundary.  */
	andcc		%o0, (64 - 1), %o4
	be,pt		%XCC, 2f
	 sub		%o4, 64, %o4
	sub		%g0, %o4, %o4	! bytes to align dst
	sub		%o2, %o4, %o2
1:	subcc		%o4, 1, %o4
	LOAD(ldub, %o1, %g1)
	STORE(stb, %g1, %o0)
	add		%o1, 1, %o1
	bne,pt		%XCC, 1b
	add		%o0, 1, %o0

	/* If the source is on a 16-byte boundary we can do
	 * the direct block copy loop.  If it is 8-byte aligned
	 * we can do the 16-byte loads offset by -8 bytes and the
	 * init stores offset by one register.
	 *
	 * If the source is not even 8-byte aligned, we need to do
	 * shifting and masking (basically integer faligndata).
	 *
	 * The careful bit with init stores is that if we store
	 * to any part of the cache line we have to store the whole
	 * cacheline else we can end up with corrupt L2 cache line
	 * contents.  Since the loop works on 64-bytes of 64-byte
	 * aligned store data at a time, this is easy to ensure.
	 */
2:
	andcc		%o1, (16 - 1), %o4
	andn		%o2, (64 - 1), %g1	! block copy loop iterator
	sub		%o2, %g1, %o2		! final sub-block copy bytes
	be,pt		%XCC, 50f
	 cmp		%o4, 8
	be,a,pt		%XCC, 10f
	 sub		%o1, 0x8, %o1

	/* Neither 8-byte nor 16-byte aligned, shift and mask.  */
	mov		%g1, %o4
	and		%o1, 0x7, %g1
	sll		%g1, 3, %g1
	mov		64, %o3
	andn		%o1, 0x7, %o1
	LOAD(ldx, %o1, %g2)
	sub		%o3, %g1, %o3
	sllx		%g2, %g1, %g2

#define SWIVEL_ONE_DWORD(SRC, TMP1, TMP2, PRE_VAL, PRE_SHIFT, POST_SHIFT, DST)\
	LOAD(ldx, SRC, TMP1); \
	srlx		TMP1, PRE_SHIFT, TMP2; \
	or		TMP2, PRE_VAL, TMP2; \
	STORE_INIT(TMP2, DST); \
	sllx		TMP1, POST_SHIFT, PRE_VAL;

1:	add		%o1, 0x8, %o1
	SWIVEL_ONE_DWORD(%o1, %g3, %o5, %g2, %o3, %g1, %o0 + 0x00)
	add		%o1, 0x8, %o1
	SWIVEL_ONE_DWORD(%o1, %g3, %o5, %g2, %o3, %g1, %o0 + 0x08)
	add		%o1, 0x8, %o1
	SWIVEL_ONE_DWORD(%o1, %g3, %o5, %g2, %o3, %g1, %o0 + 0x10)
	add		%o1, 0x8, %o1
	SWIVEL_ONE_DWORD(%o1, %g3, %o5, %g2, %o3, %g1, %o0 + 0x18)
	add		%o1, 32, %o1
	LOAD(prefetch, %o1, #one_read)
	sub		%o1, 32 - 8, %o1
	SWIVEL_ONE_DWORD(%o1, %g3, %o5, %g2, %o3, %g1, %o0 + 0x20)
	add		%o1, 8, %o1
	SWIVEL_ONE_DWORD(%o1, %g3, %o5, %g2, %o3, %g1, %o0 + 0x28)
	add		%o1, 8, %o1
	SWIVEL_ONE_DWORD(%o1, %g3, %o5, %g2, %o3, %g1, %o0 + 0x30)
	add		%o1, 8, %o1
	SWIVEL_ONE_DWORD(%o1, %g3, %o5, %g2, %o3, %g1, %o0 + 0x38)
	subcc		%o4, 64, %o4
	bne,pt		%XCC, 1b
	 add		%o0, 64, %o0

#undef SWIVEL_ONE_DWORD

	srl		%g1, 3, %g1
	ba,pt		%XCC, 60f
	 add		%o1, %g1, %o1

10:	/* Destination is 64-byte aligned, source was only 8-byte
	 * aligned but it has been subtracted by 8 and we perform
	 * one twin load ahead, then add 8 back into source when
	 * we finish the loop.
	 */
	LOAD_TWIN(%o1, %o4, %o5)
1:	add		%o1, 16, %o1
	LOAD_TWIN(%o1, %g2, %g3)
	add		%o1, 16 + 32, %o1
	LOAD(prefetch, %o1, #one_read)
	sub		%o1, 32, %o1
	STORE_INIT(%o5, %o0 + 0x00)		! initializes cache line
	STORE_INIT(%g2, %o0 + 0x08)
	LOAD_TWIN(%o1, %o4, %o5)
	add		%o1, 16, %o1
	STORE_INIT(%g3, %o0 + 0x10)
	STORE_INIT(%o4, %o0 + 0x18)
	LOAD_TWIN(%o1, %g2, %g3)
	add		%o1, 16, %o1
	STORE_INIT(%o5, %o0 + 0x20)
	STORE_INIT(%g2, %o0 + 0x28)
	LOAD_TWIN(%o1, %o4, %o5)
	STORE_INIT(%g3, %o0 + 0x30)
	STORE_INIT(%o4, %o0 + 0x38)
	subcc		%g1, 64, %g1
	bne,pt		%XCC, 1b
	 add		%o0, 64, %o0

	ba,pt		%XCC, 60f
	 add		%o1, 0x8, %o1

50:	/* Destination is 64-byte aligned, and source is 16-byte
	 * aligned.
	 */
1:	LOAD_TWIN(%o1, %o4, %o5)
	add	%o1, 16, %o1
	LOAD_TWIN(%o1, %g2, %g3)
	add	%o1, 16 + 32, %o1
	LOAD(prefetch, %o1, #one_read)
	sub	%o1, 32, %o1
	STORE_INIT(%o4, %o0 + 0x00)		! initializes cache line
	STORE_INIT(%o5, %o0 + 0x08)
	LOAD_TWIN(%o1, %o4, %o5)
	add	%o1, 16, %o1
	STORE_INIT(%g2, %o0 + 0x10)
	STORE_INIT(%g3, %o0 + 0x18)
	LOAD_TWIN(%o1, %g2, %g3)
	add	%o1, 16, %o1
	STORE_INIT(%o4, %o0 + 0x20)
	STORE_INIT(%o5, %o0 + 0x28)
	STORE_INIT(%g2, %o0 + 0x30)
	STORE_INIT(%g3, %o0 + 0x38)
	subcc	%g1, 64, %g1
	bne,pt	%XCC, 1b
	 add	%o0, 64, %o0
	/* fall through */

60:
	/* %o2 contains any final bytes still needed to be copied
	 * over. If anything is left, we copy it one byte at a time.
	 */
	wr		%g0, ASI_PNF, %asi
	brz,pt		%o2, 85f
	 sub		%o0, %o1, %o3
	ba,a,pt		%XCC, 90f

	.align		64
70: /* 16 < len <= 64 */
	bne,pn		%XCC, 75f
	 sub		%o0, %o1, %o3

72:
	andn		%o2, 0xf, %o4
	and		%o2, 0xf, %o2
1:	subcc		%o4, 0x10, %o4
	LOAD(ldx, %o1, %o5)
	add		%o1, 0x08, %o1
	LOAD(ldx, %o1, %g1)
	sub		%o1, 0x08, %o1
	STORE(stx, %o5, %o1 + %o3)
	add		%o1, 0x8, %o1
	STORE(stx, %g1, %o1 + %o3)
	bgu,pt		%XCC, 1b
	 add		%o1, 0x8, %o1
73:	andcc		%o2, 0x8, %g0
	be,pt		%XCC, 1f
	 nop
	sub		%o2, 0x8, %o2
	LOAD(ldx, %o1, %o5)
	STORE(stx, %o5, %o1 + %o3)
	add		%o1, 0x8, %o1
1:	andcc		%o2, 0x4, %g0
	be,pt		%XCC, 1f
	 nop
	sub		%o2, 0x4, %o2
	LOAD(lduw, %o1, %o5)
	STORE(stw, %o5, %o1 + %o3)
	add		%o1, 0x4, %o1
1:	cmp		%o2, 0
	be,pt		%XCC, 85f
	 nop
	ba,pt		%XCC, 90f
	 nop

75:
	andcc		%o0, 0x7, %g1
	sub		%g1, 0x8, %g1
	be,pn		%icc, 2f
	 sub		%g0, %g1, %g1
	sub		%o2, %g1, %o2

1:	subcc		%g1, 1, %g1
	LOAD(ldub, %o1, %o5)
	STORE(stb, %o5, %o1 + %o3)
	bgu,pt		%icc, 1b
	 add		%o1, 1, %o1

2:	add		%o1, %o3, %o0
	andcc		%o1, 0x7, %g1
	bne,pt		%icc, 8f
	 sll		%g1, 3, %g1

	cmp		%o2, 16
	bgeu,pt		%icc, 72b
	 nop
	ba,a,pt		%XCC, 73b

8:	mov		64, %o3
	andn		%o1, 0x7, %o1
	LOAD(ldx, %o1, %g2)
	sub		%o3, %g1, %o3
	andn		%o2, 0x7, %o4
	sllx		%g2, %g1, %g2
1:	add		%o1, 0x8, %o1
	LOAD(ldx, %o1, %g3)
	subcc		%o4, 0x8, %o4
	srlx		%g3, %o3, %o5
	or		%o5, %g2, %o5
	STORE(stx, %o5, %o0)
	add		%o0, 0x8, %o0
	bgu,pt		%icc, 1b
	 sllx		%g3, %g1, %g2

	srl		%g1, 3, %g1
	andcc		%o2, 0x7, %o2
	be,pn		%icc, 85f
	 add		%o1, %g1, %o1
	ba,pt		%XCC, 90f
	 sub		%o0, %o1, %o3

	.align		64
80: /* 0 < len <= 16 */
	andcc		%o3, 0x3, %g0
	bne,pn		%XCC, 90f
	 sub		%o0, %o1, %o3

1:
	subcc		%o2, 4, %o2
	LOAD(lduw, %o1, %g1)
	STORE(stw, %g1, %o1 + %o3)
	bgu,pt		%XCC, 1b
	 add		%o1, 4, %o1

85:	retl
	 mov		%g5, %o0

	.align		32
90:
	subcc		%o2, 1, %o2
	LOAD(ldub, %o1, %g1)
	STORE(stb, %g1, %o1 + %o3)
	bgu,pt		%XCC, 90b
	 add		%o1, 1, %o1
	retl
	 mov		%g5, %o0

END(memcpy)

#define RMOVE_BIGCHUNK(src, dst, offset, t0, t1, t2, t3)	\
	ldx		[%src - offset - 0x20], %t0; 		\
	ldx		[%src - offset - 0x18], %t1; 		\
	ldx		[%src - offset - 0x10], %t2; 		\
	ldx		[%src - offset - 0x08], %t3; 		\
	stw		%t0, [%dst - offset - 0x1c]; 		\
	srlx		%t0, 32, %t0;				\
	stw		%t0, [%dst - offset - 0x20]; 		\
	stw		%t1, [%dst - offset - 0x14]; 		\
	srlx		%t1, 32, %t1;				\
	stw		%t1, [%dst - offset - 0x18]; 		\
	stw		%t2, [%dst - offset - 0x0c]; 		\
	srlx		%t2, 32, %t2;				\
	stw		%t2, [%dst - offset - 0x10]; 		\
	stw		%t3, [%dst - offset - 0x04];		\
	srlx		%t3, 32, %t3;				\
	stw		%t3, [%dst - offset - 0x08];

#define RMOVE_BIGALIGNCHUNK(src, dst, offset, t0, t1, t2, t3)	\
	ldx		[%src - offset - 0x20], %t0; 		\
	ldx		[%src - offset - 0x18], %t1; 		\
	ldx		[%src - offset - 0x10], %t2; 		\
	ldx		[%src - offset - 0x08], %t3; 		\
	stx		%t0, [%dst - offset - 0x20]; 		\
	stx		%t1, [%dst - offset - 0x18]; 		\
	stx		%t2, [%dst - offset - 0x10]; 		\
	stx		%t3, [%dst - offset - 0x08];		\
	ldx		[%src - offset - 0x40], %t0; 		\
	ldx		[%src - offset - 0x38], %t1; 		\
	ldx		[%src - offset - 0x30], %t2; 		\
	ldx		[%src - offset - 0x28], %t3; 		\
	stx		%t0, [%dst - offset - 0x40]; 		\
	stx		%t1, [%dst - offset - 0x38]; 		\
	stx		%t2, [%dst - offset - 0x30]; 		\
	stx		%t3, [%dst - offset - 0x28];

#define RMOVE_LASTCHUNK(src, dst, offset, t0, t1, t2, t3)	\
	ldx		[%src + offset + 0x00], %t0;		\
	ldx		[%src + offset + 0x08], %t1; 		\
	stw		%t0, [%dst + offset + 0x04]; 		\
	srlx		%t0, 32, %t2;				\
	stw		%t2, [%dst + offset + 0x00]; 		\
	stw		%t1, [%dst + offset + 0x0c]; 		\
	srlx		%t1, 32, %t3;				\
	stw		%t3, [%dst + offset + 0x08];

#define RMOVE_LASTALIGNCHUNK(src, dst, offset, t0, t1)		\
	ldx		[%src + offset + 0x00], %t0; 		\
	ldx		[%src + offset + 0x08], %t1; 		\
	stx		%t0, [%dst + offset + 0x00]; 		\
	stx		%t1, [%dst + offset + 0x08];

	.align		32
228:	andcc		%o2, 1, %g0
	be,pt		%icc, 2f+4
1:	 ldub		[%o1 - 1], %o5
	sub		%o1, 1, %o1
	sub		%o0, 1, %o0
	subcc		%o2, 1, %o2
	be,pn		%xcc, 229f
	 stb		%o5, [%o0]
2:	ldub		[%o1 - 1], %o5
	sub		%o0, 2, %o0
	ldub		[%o1 - 2], %g5
	sub		%o1, 2, %o1
	subcc		%o2, 2, %o2
	stb		%o5, [%o0 + 1]
	bne,pt		%xcc, 2b
	 stb		%g5, [%o0]
229:	retl
	 mov		%g4, %o0
out:	retl
	 mov		%g5, %o0

	.align		32
ENTRY(memmove)
	mov		%o0, %g5
#ifndef USE_BPR
	srl		%o2, 0, %o2
#endif
	brz,pn		%o2, out
	 sub		%o0, %o1, %o4
	cmp		%o4, %o2
	bgeu,pt		%XCC, 218b
	 mov		%o0, %g4
	add		%o0, %o2, %o0
220:	add		%o1, %o2, %o1
	cmp		%o2, 15
	bleu,pn		%xcc, 228b
	 andcc		%o0, 7, %g2
	sub		%o0, %o1, %g5
	andcc		%g5, 3, %o5
	bne,pn		%xcc, 232f
	 andcc		%o1, 3, %g0
	be,a,pt		%xcc, 236f
	 andcc		%o1, 4, %g0
	andcc		%o1, 1, %g0
	be,pn		%xcc, 4f
	 andcc		%o1, 2, %g0
	ldub		[%o1 - 1], %g2
	sub		%o1, 1, %o1
	sub		%o0, 1, %o0
	sub		%o2, 1, %o2
	be,pn		%xcc, 5f
	 stb		%g2, [%o0]
4:	lduh		[%o1 - 2], %g2
	sub		%o1, 2, %o1
	sub		%o0, 2, %o0
	sub		%o2, 2, %o2
	sth		%g2, [%o0]
5:	andcc		%o1, 4, %g0
236:	be,a,pn		%xcc, 2f
	 andcc		%o2, -128, %g6
	lduw		[%o1 - 4], %g5
	sub		%o1, 4, %o1
	sub		%o0, 4, %o0
	sub		%o2, 4, %o2
	stw		%g5, [%o0]
	andcc		%o2, -128, %g6
2:	be,pn		%xcc, 235f
	 andcc		%o0, 4, %g0
	be,pn		%xcc, 282f + 4
5:	RMOVE_BIGCHUNK(o1, o0, 0x00, g1, g3, g5, o5)
	RMOVE_BIGCHUNK(o1, o0, 0x20, g1, g3, g5, o5)
	RMOVE_BIGCHUNK(o1, o0, 0x40, g1, g3, g5, o5)
	RMOVE_BIGCHUNK(o1, o0, 0x60, g1, g3, g5, o5)
	subcc		%g6, 128, %g6
	sub		%o1, 128, %o1
	bne,pt		%xcc, 5b
	 sub		%o0, 128, %o0
235:	andcc		%o2, 0x70, %g6
41:	be,pn		%xcc, 280f
	 andcc		%o2, 8, %g0

279:	rd		%pc, %o5
	sll		%g6, 1, %g5
	sub		%o1, %g6, %o1
	sub		%o5, %g5, %o5
	jmpl		%o5 + %lo(280f - 279b), %g0
	 sub		%o0, %g6, %o0
	RMOVE_LASTCHUNK(o1, o0, 0x60, g2, g3, g5, o5)
	RMOVE_LASTCHUNK(o1, o0, 0x50, g2, g3, g5, o5)
	RMOVE_LASTCHUNK(o1, o0, 0x40, g2, g3, g5, o5)
	RMOVE_LASTCHUNK(o1, o0, 0x30, g2, g3, g5, o5)
	RMOVE_LASTCHUNK(o1, o0, 0x20, g2, g3, g5, o5)
	RMOVE_LASTCHUNK(o1, o0, 0x10, g2, g3, g5, o5)
	RMOVE_LASTCHUNK(o1, o0, 0x00, g2, g3, g5, o5)
280:	be,pt		%xcc, 281f
	 andcc		%o2, 4, %g0
	ldx		[%o1 - 8], %g2
	sub		%o0, 8, %o0
	stw		%g2, [%o0 + 4]
	sub		%o1, 8, %o1
	srlx		%g2, 32, %g2
	stw		%g2, [%o0]
281:	be,pt		%xcc, 1f
	 andcc		%o2, 2, %g0
	lduw		[%o1 - 4], %g2
	sub		%o1, 4, %o1
	stw		%g2, [%o0 - 4]
	sub		%o0, 4, %o0
1:	be,pt		%xcc, 1f
	 andcc		%o2, 1, %g0
	lduh		[%o1 - 2], %g2
	sub		%o1, 2, %o1
	sth		%g2, [%o0 - 2]
	sub		%o0, 2, %o0
1:	be,pt		%xcc, 211f
	 nop
	ldub		[%o1 - 1], %g2
	stb		%g2, [%o0 - 1]
211:	retl
	 mov		%g4, %o0

282:	RMOVE_BIGALIGNCHUNK(o1, o0, 0x00, g1, g3, g5, o5)
	RMOVE_BIGALIGNCHUNK(o1, o0, 0x40, g1, g3, g5, o5)
	subcc		%g6, 128, %g6
	sub		%o1, 128, %o1
	bne,pt		%xcc, 282b
	 sub		%o0, 128, %o0
	andcc		%o2, 0x70, %g6
	be,pn		%xcc, 284f
	 andcc		%o2, 8, %g0

283:	rd		%pc, %o5
	sub		%o1, %g6, %o1
	sub		%o5, %g6, %o5
	jmpl		%o5 + %lo(284f - 283b), %g0
	 sub		%o0, %g6, %o0
	RMOVE_LASTALIGNCHUNK(o1, o0, 0x60, g2, g3)
	RMOVE_LASTALIGNCHUNK(o1, o0, 0x50, g2, g3)
	RMOVE_LASTALIGNCHUNK(o1, o0, 0x40, g2, g3)
	RMOVE_LASTALIGNCHUNK(o1, o0, 0x30, g2, g3)
	RMOVE_LASTALIGNCHUNK(o1, o0, 0x20, g2, g3)
	RMOVE_LASTALIGNCHUNK(o1, o0, 0x10, g2, g3)
	RMOVE_LASTALIGNCHUNK(o1, o0, 0x00, g2, g3)
284:	be,pt		%xcc, 285f
	 andcc		%o2, 4, %g0
	ldx		[%o1 - 8], %g2
	sub		%o0, 8, %o0
	sub		%o1, 8, %o1
	stx		%g2, [%o0]
285:	be,pt		%xcc, 1f
	 andcc		%o2, 2, %g0
	lduw		[%o1 - 4], %g2
	sub		%o0, 4, %o0
	sub		%o1, 4, %o1
	stw		%g2, [%o0]
1:	be,pt		%xcc, 1f
	 andcc		%o2, 1, %g0
	lduh		[%o1 - 2], %g2
	sub		%o0, 2, %o0
	sub		%o1, 2, %o1
	sth		%g2, [%o0]
1:	be,pt		%xcc, 1f
	 nop
	ldub		[%o1 - 1], %g2
	stb		%g2, [%o0 - 1]
1:	retl
	 mov		%g4, %o0

232:	ldub		[%o1 - 1], %g5
	sub		%o1, 1, %o1
	sub		%o0, 1, %o0
	subcc		%o2, 1, %o2
	bne,pt		%xcc, 232b
	 stb		%g5, [%o0]
234:	retl
	 mov		%g4, %o0
END(memmove)

#ifdef USE_BPR
weak_alias (memcpy, __align_cpy_1)
weak_alias (memcpy, __align_cpy_2)
weak_alias (memcpy, __align_cpy_4)
weak_alias (memcpy, __align_cpy_8)
weak_alias (memcpy, __align_cpy_16)
#endif
libc_hidden_builtin_def (memcpy)
libc_hidden_builtin_def (memmove)