benchmark for type checks

typecheck-bench.linq

#LINQPad optimize+

class Info {

  public char Type;

}

class Base {
  
  public Base() : this('B') {
  }
  
  protected Base(char type) {
    this.Info = new Info { Type = type };
  }

  public Info Info { get; private set; }

}

class Derived : Base {
  
  public Derived() : base('D') { }
  
}

public class TypeCheckBenchmarks {

  private readonly Base Object1 = new Base();

  private readonly Base Object2 = new Derived();

  int counter = 0;

  [Benchmark]
  public void TestUsingIsOperatorWhenFalse()
  {
    if (this.Object1 is Derived)
    {
      ++counter;
    }
    else
    {
      --counter;
    }
    if (this.Object2 is Base)
    {
      ++counter;
    }
    else
    {
      --counter;
    }
  }

  [Benchmark]
  public void TestUsingIsOperatorWhenTrue()
  {
    if (this.Object1 is Base)
    {
      ++counter;
    }
    else
    {
      --counter;
    }
    if (this.Object2 is Derived)
    {
      ++counter;
    }
    else
    {
      --counter;
    }
  }

  [Benchmark]
  public void TestUsingPropertyWhenFalse()
  {
    if (this.Object1.Info.Type == 'D')
    {
      ++counter;
    }
    else
    {
      --counter;
    }
    if (this.Object2.Info.Type == 'B')
    {
      ++counter;
    }
    else
    {
      --counter;
    }
  }

  [Benchmark]
  public void TestUsingPropertyWhenTrue()
  {
    if (this.Object1.Info.Type == 'B')
    {
      ++counter;
    }
    else {
      --counter;
    }
    if (this.Object2.Info.Type == 'D')
    {
      ++counter;
    }
    else
    {
      --counter;
    }
  }

  [Benchmark]
  public void TestUsingTypeOfWhenFalse()
  {
    if (this.Object1.GetType() == typeof(Derived))
    {
      ++counter;
    }
    else
    {
      --counter;
    }
    if (this.Object2.GetType() == typeof(Base))
    {
      ++counter;
    }
    else
    {
      --counter;
    }
  }

  [Benchmark]
  public void TestUsingTypeOfWhenTrue()
  {
    if (this.Object1.GetType() == typeof(Base))
    {
      ++counter;
    }
    else
    {
      --counter;
    }
    if (this.Object2.GetType() == typeof(Derived))
    {
      ++counter;
    }
    else
    {
      --counter;
    }
  }
}

public static void Main() {
  BenchmarkRunner.Run<TypeCheckBenchmarks>();
}