blob: b4b671f773e3f07a4322c64a924a03e0c6fb9434 [file] [log] [blame]
// 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"
// void runtime·memclr(void*, uintptr)
TEXT runtime·memclr(SB), NOSPLIT, $0-8
MOVL ptr+0(FP), DI
MOVL n+4(FP), BX
XORL AX, AX
clr_tail:
TESTL BX, BX
JEQ clr_0
CMPL BX, $2
JBE clr_1or2
CMPL BX, $4
JBE clr_3or4
CMPL BX, $8
JBE clr_5through8
CMPL BX, $16
JBE clr_9through16
MOVL BX, CX
SHRL $2, CX
REP
STOSL
ANDL $3, BX
JNE clr_tail
RET
clr_1or2:
MOVB AX, (DI)
MOVB AX, -1(DI)(BX*1)
RET
clr_0:
RET
clr_3or4:
MOVW AX, (DI)
MOVW AX, -2(DI)(BX*1)
RET
clr_5through8:
MOVL AX, (DI)
MOVL AX, -4(DI)(BX*1)
RET
clr_9through16:
MOVL AX, (DI)
MOVL AX, 4(DI)
MOVL AX, -8(DI)(BX*1)
MOVL AX, -4(DI)(BX*1)
RET