[You must know. NET] The 26th time: Understanding metadata and IL (bottom)

The book is answered:

24th Time: Understanding metadata and IL (upper), 25th back: Understanding Metadata and IL (medium)

Let's move on.

Finally, to say that the metadata and IL role in JIT compilation, although the two-round foreshadowing is extravagant, but it is not too much, because only sufficient knowledge to have enough experience, technology is the same. So, we begin to follow the path of the method call, following the power that metadata and il contribute in that mysterious moment.

5 Meta data and IL at JIT compile time

The CLR ultimately executes only the local machine code, so JIT compilation works by parsing the IL code into machine code execution at run time. For JIT compilation, we will have a dedicated space to fully understand, this article will focus only on the metadata and IL in the execution of the program and participate in the details of the role. First, the IL is executed based on the stack, when executing method calls, method parameters, local variables, and return values are allocated on the stack and execute their invocation process, and since it is concerned with JIT compilation, we naturally focus on the execution of the method, because JIT compilation is triggered by executing a method call.

First, add some new material to the code starting with this article:

//　Release　:　code04,　2009/02/24
//　Author　:　Anytao,　http://www.anytao.com
//　List　　:　Base.cs
public　class　Base
{
　　 public　void　M()
　　 {
　　　　 Console.WriteLine("M　in　Base");
　　 }

　　 public　virtual　void　N()
　　 {
　　　　 Console.WriteLine("N　in　Base");
　　 }
}

And also:

//　Release　:　code05,　2009/02/24
//　Author　:　Anytao,　http://www.anytao.com
//　List　　:　Three.cs
public　class　Three　:　Base
{
　　 private　static　int　ID　{　get;　set;　}

　　 public　override　void　N()
　　 {
　　　　 //Something　new　in　Three
　　　　 Console.WriteLine("N　in　Three");
　　 }

　　 public　void　M()
　　 {
　　　　 Console.WriteLine("M　in　Three");

　　　　 M1();
　　 }

　　 public　void　M1()
　　 {
　　　　 Console.WriteLine("M1　in　Three");
　　 }
}

There are also code execution:

static　void　Main(string[]　args)
{
　　 Base　three　=　new　Three();
　　 three.M();
　　 three.N();
}