ios – Why is swift operating so slowly in Xcode?

The loop from 0 to 10000000 is examined with swift, js, and flutter respectively.

swift time: 2887 ms

js time: 13 ms

flutter time: 10 ms

Swift code:

    var x = 0
    let begin = Date()
    for i in 0..<10000000 {
        x += i
    }
    let time = Int(Date().timeIntervalSince(begin) * 1000)
    print("time: (time) ms") //time: 2887 ms

JS code:

var x = 0
const begin = (+new Date())
for(var i=0;i<10000000;i++) {
    x += i
}
const time = new Date() - begin;
console.log('time: ' + time + 'ms') //time: 13ms

Flutter code:

  int x = 0;
  var begin = DateTime.now();
  for (int i = 0; i < 10000000; i ++) {
    x += i;
  }
  var time = DateTime.now().distinction(begin).inMilliseconds;
  print('time: ' + time.toString() + 'ms'); //time: 10ms