/// <summary>
/// This thunk creates a delegate from a native function pointer
/// by first creating a PInvokeDelegateWrapper from the function pointer
/// and then creating the delegate from the Invoke method of the wrapper
///
/// Generated IL:
/// ldarg 0
/// newobj PInvokeDelegateWrapper.ctor
/// dup
/// ldvirtftn PInvokeDelegateWrapper.Invoke
/// newobj DelegateType.ctor
/// ret
///
/// Equivalent C#
/// return new DelegateType(new PInvokeDelegateWrapper(functionPointer).Invoke)
/// </summary>
public override MethodIL EmitIL()
{
var emitter = new ILEmitter();
ILCodeStream codeStream = emitter.NewCodeStream();
codeStream.EmitLdArg(0);
codeStream.Emit(ILOpcode.newobj, emitter.NewToken(
_interopStateManager.GetPInvokeDelegateWrapper(DelegateType)
.GetPInvokeDelegateWrapperMethod(PInvokeDelegateWrapperMethodKind.Constructor)));
codeStream.Emit(ILOpcode.dup);
codeStream.Emit(ILOpcode.ldvirtftn, emitter.NewToken(
_interopStateManager.GetPInvokeDelegateWrapper(DelegateType)
.GetPInvokeDelegateWrapperMethod(PInvokeDelegateWrapperMethodKind.Invoke)));
codeStream.Emit(ILOpcode.newobj, emitter.NewToken(
_delegateType.GetMethod(".ctor",
new MethodSignature(MethodSignatureFlags.None,
genericParameterCount: 0,
returnType: Context.GetWellKnownType(WellKnownType.Void),
parameters: new TypeDesc[] { Context.GetWellKnownType(WellKnownType.Object),
Context.GetWellKnownType(WellKnownType.IntPtr) }
))));
codeStream.Emit(ILOpcode.ret);
return(emitter.Link(this));
}