@swift-5.0.3 -O
import Foundation func time(label: String, f: ()->Void) { let start = Date() f() print("\(label): elapsed time: ", Date().timeIntervalSince(start), "sec") } var x = [Int](0..<65536) x.withUnsafeMutableBufferPointer { bp in time(label: "Slice") { bp[0..<60000].sort() } time(label: "Rebase") { var rebase = UnsafeMutableBufferPointer(rebasing: bp[0..<60000]) rebase.sort() } }
(edited)