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// Copyright 2014 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"
// See memclrNoHeapPointers Go doc for important implementation constraints.
// func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr)
TEXT runtime·memclrNoHeapPointers(SB), NOSPLIT, $0-8
MOVL ptr+0(FP), DI
MOVL n+4(FP), BX
XORL AX, AX
tail:
TESTL BX, BX
JEQ _0
CMPL BX, $2
JBE _1or2
CMPL BX, $4
JB _3
JE _4
CMPL BX, $8
JBE _5through8
CMPL BX, $16
JBE _9through16
MOVL BX, CX
SHRL $2, CX
REP
STOSL
ANDL $3, BX
JNE tail
RET
_1or2:
MOVB AX, (DI)
MOVB AX, -1(DI)(BX*1)
RET
_0:
RET
_3:
MOVW AX, (DI)
MOVB AX, 2(DI)
RET
_4:
// We need a separate case for 4 to make sure we clear pointers atomically.
MOVL AX, (DI)
RET
_5through8:
MOVL AX, (DI)
MOVL AX, -4(DI)(BX*1)
RET
_9through16:
MOVL AX, (DI)
MOVL AX, 4(DI)
MOVL AX, -8(DI)(BX*1)
MOVL AX, -4(DI)(BX*1)
RET
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