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//===----------------------------------------------------------------------===//
//
// This source file is part of the Swift open source project
//
// Copyright (c) 2025 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See http://swift.org/LICENSE.txt for license information
// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
/// Common math and bit-wise operations
public extension Int {
/// Returns the value with the least-significant bit removed.
func withoutLSB() -> Int {
return self & (self - 1)
}
/// Check if the value is a power-of-two.
func isPowerOfTwo() -> Bool {
// A value is a power of two if it isn't zero and removing one bit makes it zero.
return self != 0 && withoutLSB() == 0
}
/// Return the next larger power-of-two, or 0 on overflow.
func nextPowerOfTwo() -> Int {
// Compute the next power of two by filling all bits below the MSB, then adding one.
var result = self
result |= result >> 1
result |= result >> 2
result |= result >> 4
result |= result >> 8
result |= result >> 16
result |= result >> 32
return result + 1
}
/// Return the smallest power-of-two greater than or equal to the value.
func roundUpToPowerOfTwo() -> Int {
return isPowerOfTwo() ? self : nextPowerOfTwo()
}
/// Returns the smallest even number greater than or equal to the value.
func nextEvenNumber() -> Int {
return self % 2 == 0 ? self : self + 1
}
}
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