зеркало из https://github.com/golang/tools.git
22 строки
524 B
Go
22 строки
524 B
Go
// Copyright 2015 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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//go:build amd64 && !appengine && !gccgo
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// +build amd64,!appengine,!gccgo
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package intsets
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func popcnt(x word) int
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func havePOPCNT() bool
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var hasPOPCNT = havePOPCNT()
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// popcount returns the population count (number of set bits) of x.
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func popcount(x word) int {
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if hasPOPCNT {
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return popcnt(x)
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}
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return popcountTable(x) // faster than Hacker's Delight
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}
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