It's using some non-optimal patterns that you would not normally use in Swift for code if you wanted it to perform well. (There's a nice performance analysis if you click in, showing that it's using ARC in an inner loop, which is taking 3/4th of the time. That's not something you need to do.)
It's using some non-optimal patterns that you would not normally use in Swift for code if you wanted it to perform well. (There's a nice performance analysis if you click in, showing that it's using ARC in an inner loop, which is taking 3/4th of the time. That's not something you need to do.)