public static MethodIL EmitIL(MethodDesc method)
{
Debug.Assert(method.OwningType.IsDelegate);
Debug.Assert(method.IsRuntimeImplemented);
if (method.Name == "BeginInvoke" || method.Name == "EndInvoke")
{
// BeginInvoke and EndInvoke are not supported on .NET Core
ILEmitter emit = new ILEmitter();
ILCodeStream codeStream = emit.NewCodeStream();
MethodDesc notSupportedExceptionHelper = method.Context.GetHelperEntryPoint("ThrowHelpers", "ThrowPlatformNotSupportedException");
codeStream.EmitCallThrowHelper(emit, notSupportedExceptionHelper);
return(emit.Link());
}
if (method.Name == ".ctor")
{
TypeSystemContext context = method.Context;
ILEmitter emit = new ILEmitter();
TypeDesc delegateType = context.GetWellKnownType(WellKnownType.MulticastDelegate).BaseType;
MethodDesc objectCtorMethod = context.GetWellKnownType(WellKnownType.Object).GetDefaultConstructor();
FieldDesc functionPointerField = delegateType.GetKnownField("m_functionPointer");
FieldDesc firstParameterField = delegateType.GetKnownField("m_firstParameter");
ILCodeStream codeStream = emit.NewCodeStream();
codeStream.EmitLdArg(0);
codeStream.Emit(ILOpcode.call, emit.NewToken(objectCtorMethod));
codeStream.EmitLdArg(0);
codeStream.EmitLdArg(1);
codeStream.Emit(ILOpcode.stfld, emit.NewToken(firstParameterField));
codeStream.EmitLdArg(0);
codeStream.EmitLdArg(2);
codeStream.Emit(ILOpcode.stfld, emit.NewToken(functionPointerField));
codeStream.Emit(ILOpcode.ret);
return(emit.Link());
}
return(null);
}