You can take an arbitrary pointer value in a function, look up its location, and do the copy if necessary, instead of requiring multiple entry points for CPU an

You can take an arbitrary pointer value in a function, look up its location, and do the copy if necessary, instead of requiring multiple entry points for CPU and GPU pointers. This also simplifies multi-GPU programming a lot--copy from one arbitrary pointer to another and it just works, instead of having to specify which device the copies are going to or anything like that.