Making calls from C to C# with IL2CPP instead of mono_runtime_invoke

I am trying to figure out how to make calls from C to C# with IL2CPP. For Mono, I would do this by calling mono_runtime_invoke from C using the methods described here: http://www.jerrodputman.com/2010/01/10/the-unityobjective-c-divide

According to the Unity Manual (http://docs.unity3d.com/Manual/iphone-64bit.html):
Making calls from C to C# with IL2CPP instead of mono_runtime_invoke