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UInt+reversed.swift
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UInt+reversed.swift
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//===----------------------------------------------------------------------===//
//
// This source file is part of the Swift Collections open source project
//
// Copyright (c) 2022 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
//
//===----------------------------------------------------------------------===//
extension UInt {
@inlinable
public var _reversed: UInt {
// https://graphics.stanford.edu/~seander/bithacks.html#ReverseParallel
var shift: UInt = UInt(UInt.bitWidth)
var mask: UInt = ~0;
var result = self
while true {
shift &>>= 1
guard shift > 0 else { break }
mask ^= mask &<< shift
result = ((result &>> shift) & mask) | ((result &<< shift) & ~mask)
}
return result
}
}