swift いい加减なLoopテスト - 匿名による处理指定を固定アドレスに。

Posted 2021-05-19

//: Playground - noun: a place where people can play

//import UIKit
import Foundation

var str = "Hello, playground"

let MAX = 100//_000
let testValues = Array(count:MAX, repeatedValue:2)
var total = 0

struct runTest {
    var myName:String
    let myFunc:Void -> Void

    var startTime=0.0,interval=0.0

    init(sign:String, f:(Void) -> Void) {
        self.myName = sign
        self.myFunc = f
    }


    mutating func reset() {
        total = 0
        self.startTime = currentTime()
    }

    func currentTime() -> Double {
        return ((CFAbsoluteTimeGetCurrent() as Double) * 1000.0)
    }

    mutating func letUsLoopin() {
        reset()
        self.myFunc()
        self.interval += currentTime() - startTime
    }
}

func test01() {
     for i in 0 ..< testValues.count {
         total += testValues[i]
    }
}

func test02() {
    let max = testValues.count - 1
    for i in 0...max {
        total += testValues[i]
    }
}

func test03() {
    for v in testValues {
        total += v
    }
}

func test04() {
    var test = testValues.count - 1
    while test > 0 {
        total += testValues[test]
        test -= 1
    }
}

// 実行関数配列
var runArray :[runTest] = [runTest(sign:"closed for",
    f: test01),

    runTest(sign:"opened for",
    f: test02),

    runTest(sign:"zipIndexing",
        f: {for (index,v) in testValues.enumerate() {
            total += v
        }
    }),

    runTest(sign: "for-in",
        f: test03),

    runTest(sign: "while",
    f: test04)
]

// 実行時間記録
var runTimes = [Double](count:runArray.count, repeatedValue:0.0)
let trialTimes = 1_000_000

for i in 0 ..< trialTimes {
    let idx = i % runArray.count
    runArray[idx].letUsLoopin()
}

for x in runArray {
    print("\"\(x.myName)\" : \(x.interval)," )
}

// struct
// closed for : 59406.6962890625
// opened for : 59429.0154418945
// zipIndexing : 59891.3329467773
// for-in : 59426.2610473633

// class