| //===--- RandomValues.swift -----------------------------------------------===// |
| // |
| // This source file is part of the Swift.org open source project |
| // |
| // Copyright (c) 2018 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 |
| // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors |
| // |
| //===----------------------------------------------------------------------===// |
| |
| import TestsUtils |
| |
| // |
| // Benchmark generating lots of random values. Measures the performance of |
| // the default random generator and the algorithms for generating integers |
| // and floating-point values. |
| // |
| |
| public let RandomValues = [ |
| BenchmarkInfo(name: "RandomIntegersDef", runFunction: run_RandomIntegersDef, tags: [.api]), |
| BenchmarkInfo(name: "RandomIntegersLCG", runFunction: run_RandomIntegersLCG, tags: [.api]), |
| BenchmarkInfo(name: "RandomDoubleDef", runFunction: run_RandomDoubleDef, tags: [.api]), |
| BenchmarkInfo(name: "RandomDoubleLCG", runFunction: run_RandomDoubleLCG, tags: [.api]), |
| ] |
| |
| /// A linear congruential PRNG. |
| struct LCRNG: RandomNumberGenerator { |
| private var state: UInt64 |
| |
| init(seed: Int) { |
| state = UInt64(truncatingIfNeeded: seed) |
| for _ in 0..<10 { _ = next() } |
| } |
| |
| mutating func next() -> UInt64 { |
| state = 2862933555777941757 &* state &+ 3037000493 |
| return state |
| } |
| } |
| |
| @inline(never) |
| public func run_RandomIntegersDef(_ N: Int) { |
| for _ in 0 ..< N { |
| var x = 0 |
| for _ in 0 ..< 100_000 { |
| x &+= Int.random(in: 0...10_000) |
| } |
| blackHole(x) |
| } |
| } |
| |
| @inline(never) |
| public func run_RandomIntegersLCG(_ N: Int) { |
| for _ in 0 ..< N { |
| var x = 0 |
| var generator = LCRNG(seed: 0) |
| for _ in 0 ..< 100_000 { |
| x &+= Int.random(in: 0...10_000, using: &generator) |
| } |
| CheckResults(x == 498214315) |
| } |
| } |
| |
| @inline(never) |
| public func run_RandomDoubleDef(_ N: Int) { |
| for _ in 0 ..< N { |
| var x = 0.0 |
| for _ in 0 ..< 100_000 { |
| x += Double.random(in: -1000...1000) |
| } |
| blackHole(x) |
| } |
| } |
| |
| @inline(never) |
| public func run_RandomDoubleLCG(_ N: Int) { |
| for _ in 0 ..< N { |
| var x = 0.0 |
| var generator = LCRNG(seed: 0) |
| for _ in 0 ..< 100_000 { |
| x += Double.random(in: -1000...1000, using: &generator) |
| } |
| blackHole(x) |
| } |
| } |