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// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "textflag.h"
// This could use MOVSQ, but we use MOVSL so that if an object ends in
// a 4 byte pointer, we copy it as a unit instead of byte by byte.
TEXT runtime·memmove(SB), NOSPLIT, $0-12
MOVL to+0(FP), DI
MOVL from+4(FP), SI
MOVL n+8(FP), BX
CMPL SI, DI
JLS back
forward:
MOVL BX, CX
SHRL $2, CX
ANDL $3, BX
REP; MOVSL
MOVL BX, CX
REP; MOVSB
RET
back:
MOVL SI, CX
ADDL BX, CX
CMPL CX, DI
JLS forward
ADDL BX, DI
ADDL BX, SI
STD
MOVL BX, CX
SHRL $2, CX
ANDL $3, BX
SUBL $4, DI
SUBL $4, SI
REP; MOVSL
ADDL $3, DI
ADDL $3, SI
MOVL BX, CX
REP; MOVSB
CLD
RET
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