benchmark/single-source/ArrayOfGenericPOD.swift

//===--- ArrayOfGenericPOD.swift ------------------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2017 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
//
//===----------------------------------------------------------------------===//

// This benchmark tests creation and destruction of arrays of enum and
// generic type bound to trivial types. It should take the same time as
// ArrayOfPOD.  (In practice, it takes a little longer to construct
// the optional arrays).
//
// For comparison, we always create three arrays of 200,000 words.
// An integer enum takes two words.

class RefArray<T> {
  var array: [T]

  init(_ i:T) {
    array = [T](repeating: i, count: 100000)
  }
}

// Check the performance of destroying an array of enums (optional) where the
// enum has a single payload of trivial type. Destroying the
// elements should be a nop.
@inline(never)
func genEnumArray() {
  _ = RefArray<Int?>(3)
  // should be a nop
}

// Check the performance of destroying an array of implicit unwrapped
// optional where the optional has a single payload of trivial
// type. Destroying the elements should be a nop.
@inline(never)
func genIOUArray() {
  _ = RefArray<Int!>(3)
  // should be a nop
}

// Check the performance of destroying an array of structs where the
// struct has multiple fields of trivial type. Destroying the
// elements should be a nop.
struct S<T> {
  var x: T
  var y: T
}
@inline(never)
func genStructArray() {
  _ = RefArray<S<Int>>(S(x:3, y:4))
  // should be a nop
}

@inline(never)
public func run_ArrayOfGenericPOD(_ N: Int) {
  for _ in 0...N {
    genEnumArray()
    genIOUArray()
    genStructArray()
  }
}