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// Copyright 2015 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.
// +build amd64,!appengine,!gccgo
#include "textflag.h"
// func havePOPCNT() bool
TEXT ·havePOPCNT(SB),4,$0
MOVQ $1, AX
CPUID
SHRQ $23, CX
ANDQ $1, CX
MOVB CX, ret+0(FP)
RET
// func popcnt(word) int
TEXT ·popcnt(SB),NOSPLIT,$0-8
XORQ AX, AX
MOVQ x+0(FP), SI
// POPCNT (SI), AX is not recognized by Go assembler,
// so we assemble it ourselves.
BYTE $0xf3
BYTE $0x48
BYTE $0x0f
BYTE $0xb8
BYTE $0xc6
MOVQ AX, ret+8(FP)
RET
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