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发出MSIL以发出MSIL运行到JIT限制

reflection.emit cil c#

-1

John Alexiou · 技术社区 · 10 年前

所以我想回答 https://codegolf.stackexchange.com/q/22921/12097 并决定发出MSIL代码来进行整数加法。由于这是成功的,所以我决定发出MSIL代码,这将发出我的第一个代码。因此,调用代码构造一个方法,该方法构造一个调用 int.op_Addition 。由于JIT抱怨我做得太过分,这失败得很惨!啊!

例外情况是 System.SystemException: {"JIT Compiler encountered an internal limitation."} 在调用动态方法的最后一行。

我的问题是,我假设JIT不允许发出代码来发出代码是正确的。另一种选择是我犯了一个错误,这很可能,但我根据生成的MSIL代码检查了我的代码 Reflector .

这是代码,供您消遣:

class Program
{
    static void Main(string[] args)
    {
        int z2=Add2(1, 2);
        // z2 = "JIT Compiler encountered an internal limitation."
    }

    // Emit MSIL to emit MSIL
    public static int Add2(int x, int y)
    {
        Type delegate_type=typeof(Func<int, int, int>);
        DynamicMethod method=new DynamicMethod(typeof(Program).ToString()+".GenAdd",
            typeof(int),
            new Type[] { typeof(int), typeof(int) }, typeof(Program));
        ILGenerator generator=method.GetILGenerator();

        LocalBuilder method1=generator.DeclareLocal(typeof(DynamicMethod));
        LocalBuilder generator1=generator.DeclareLocal(typeof(ILGenerator));
        LocalBuilder add1=generator.DeclareLocal(typeof(Func<int, int, int>));
        LocalBuilder args1=generator.DeclareLocal(typeof(Type[]));
        generator.Emit(OpCodes.Ldtoken, typeof(int));            

        generator.Emit(OpCodes.Call, 
            typeof(Type).GetMethod("GetTypeFromHandle", 
                System.Reflection.BindingFlags.Public | 
                System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Callvirt,
            typeof(object).GetMethod("ToString", 
                System.Reflection.BindingFlags.Public|
                System.Reflection.BindingFlags.Instance));
        generator.Emit(OpCodes.Ldstr, ".op_Addition");                        
        generator.Emit(OpCodes.Call,                
            typeof(string).GetMethod("Concat",
                new Type[] { typeof(string), typeof(string) } ));
        generator.Emit(OpCodes.Ldtoken, typeof(int));
        generator.Emit(OpCodes.Call,
            typeof(Type).GetMethod("GetTypeFromHandle",
                System.Reflection.BindingFlags.Public|
                System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Ldc_I4, 2);
        generator.Emit(OpCodes.Newarr, typeof(Type));
        generator.Emit(OpCodes.Stloc_3);
        generator.Emit(OpCodes.Ldloc_3);
        generator.Emit(OpCodes.Ldc_I4, 0);
        generator.Emit(OpCodes.Ldtoken, typeof(int));
        generator.Emit(OpCodes.Call,
            typeof(Type).GetMethod("GetTypeFromHandle",
                System.Reflection.BindingFlags.Public|
                System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Stelem_Ref);
        generator.Emit(OpCodes.Ldloc_3);
        generator.Emit(OpCodes.Ldc_I4, 1);
        generator.Emit(OpCodes.Ldtoken, typeof(int));
        generator.Emit(OpCodes.Call,
            typeof(Type).GetMethod("GetTypeFromHandle",
                System.Reflection.BindingFlags.Public|
                System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Stelem_Ref);
        generator.Emit(OpCodes.Ldloc_3);
        generator.Emit(OpCodes.Ldtoken, typeof(Program));
        generator.Emit(OpCodes.Call,
            typeof(Type).GetMethod("GetTypeFromHandle",
                System.Reflection.BindingFlags.Public|
                System.Reflection.BindingFlags.Static));

        generator.Emit(OpCodes.Newobj,
            typeof(DynamicMethod).GetConstructor(
                new Type[] { typeof(string), typeof(Type), typeof(Type[]) }));

        generator.Emit(OpCodes.Stloc_0);
        generator.Emit(OpCodes.Ldloc_0);
        generator.Emit(OpCodes.Callvirt,
            typeof(DynamicMethod).GetMethod("GetILGenerator",
                Type.EmptyTypes));
        generator.Emit(OpCodes.Stloc_1);
        generator.Emit(OpCodes.Ldloc_1);
        generator.Emit(OpCodes.Ldtoken, typeof(int));
        generator.Emit(OpCodes.Call,
            typeof(Type).GetMethod("GetTypeFromHandle",
                System.Reflection.BindingFlags.Public|
                System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Callvirt,
            typeof(ILGenerator).GetMethod("DeclareLocal",
                new Type[] { typeof(Type) }));
        generator.Emit(OpCodes.Pop);
        generator.Emit(OpCodes.Ldloc_1);
        generator.Emit(OpCodes.Ldsfld,
            typeof(OpCodes).GetField("Ldarg_0",
                System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Callvirt,
            typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
        generator.Emit(OpCodes.Ldloc_1);
        generator.Emit(OpCodes.Ldsfld,
            typeof(OpCodes).GetField("Ldarg_1",
                System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Callvirt,
            typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
        generator.Emit(OpCodes.Ldloc_1);
        generator.Emit(OpCodes.Ldsfld,
            typeof(OpCodes).GetField("Add",
                System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Callvirt,
            typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
        generator.Emit(OpCodes.Ldloc_1);
        generator.Emit(OpCodes.Ldsfld,
            typeof(OpCodes).GetField("Stloc_0",
                System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Callvirt,
            typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
        generator.Emit(OpCodes.Ldloc_1);
        generator.Emit(OpCodes.Ldsfld,
            typeof(OpCodes).GetField("Ldloc_0",
                System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Callvirt,
            typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
        generator.Emit(OpCodes.Ldloc_1);
        generator.Emit(OpCodes.Ldsfld,
            typeof(OpCodes).GetField("Ret",
                System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Callvirt,
            typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
        generator.Emit(OpCodes.Ldloc_0);
        generator.Emit(OpCodes.Ldtoken, typeof(Func<int, int, int>));
        generator.Emit(OpCodes.Call,
            typeof(Type).GetMethod("GetTypeFromHandle",
                System.Reflection.BindingFlags.Public|
                System.Reflection.BindingFlags.Static));
        generator.Emit(OpCodes.Callvirt,
            typeof(DynamicMethod).GetMethod("CreateDelegate",
                new Type[] { typeof(Type)} ));
        generator.Emit(OpCodes.Isinst, typeof(Func<int, int, int>));
        generator.Emit(OpCodes.Stloc_2);
        generator.Emit(OpCodes.Ldloc_2);
        generator.Emit(OpCodes.Ldarg_0);
        generator.Emit(OpCodes.Ldarg_1);
        generator.Emit(OpCodes.Callvirt,
            typeof(Func<int, int, int>).GetMethod("Invoke",
                System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Instance));
        generator.Emit(OpCodes.Ret);

        Func<int, int, int> add2=method.CreateDelegate(typeof(Func<int, int, int>)) as Func<int, int, int>;

        return add2(x, y);
    }
}

我想 Add2 生成如下代码,该代码100%正确工作:

    // Emit MSIL directly
    public static int Add1(int x, int y)
    {
        Type delegate_type=typeof(Func<int, int, int>);
        DynamicMethod method = new DynamicMethod(typeof(int).ToString()+".op_Addition",
            typeof(int),
            new Type[] { typeof(int), typeof(int) }, typeof(Program));

        ILGenerator generator=method.GetILGenerator();
        LocalBuilder result=generator.DeclareLocal(typeof(int));

        generator.Emit(OpCodes.Ldarg_0);
        generator.Emit(OpCodes.Ldarg_1);
        generator.Emit(OpCodes.Add);
        generator.Emit(OpCodes.Stloc_0);
        generator.Emit(OpCodes.Ldloc_0);
        generator.Emit(OpCodes.Ret);

        Func<int, int, int> add=method.CreateDelegate(typeof(Func<int, int, int>)) as Func<int, int, int>;

        return add(x, y);
    }

1 回复 | 直到 7 年前

Ben Voigt 10 年前

我很确定JIT能够编译使用反射的代码。如果没有,您将无法使用 Reflection.Emit 曾经您生成的MSIL与C#编译器生成的MSIL经历相同的JIT过程。

当涉及到CAS检查时,会有一点不同,但我看不出有任何迹象表明您在开始时是在部分信任场景中操作的。

我看到这行:

generator.Emit(OpCodes.Newobj,
typeof(DynamicMethod).GetConstructor(
    new Type[] { typeof(string), typeof(Type), typeof(Type[]) }));

它定位 DynamicMethod(string, Type, Type[]) 创建匿名托管方法的构造函数。但在 Add1 ,你有

DynamicMethod method = new DynamicMethod(typeof(int).ToString()+".op_Addition",
                                         typeof(int),
                                         new Type[] { typeof(int), typeof(int) }, 
                                         typeof(Program));

它调用四个参数 DynamicMethod 构造函数,将方法添加到类型 Program .

因此,当您使用 newobj .