Status of getPointerSize()/getPointerTy() per address space?

Looking through recent additions, it looks like the infrastructure exists for targets to specify a per-address-space pointer size/type, but this does not seem to be used anywhere (SelectionDAGBuilder, legalizer, etc.). What is the status of this support? Is anyone actively working on it?

I'm actively working on this. I think I have most of the target independent parts ready that I'm gradually sending through review. I haven't looked at what needs to be done in SelectionDAG yet.

Awesome! What will the requirements be for the target? Is it sufficient to just override getPointerTy and add appropriate data layout strings, or will more hooks be needed?

I think that should be it

It should just be enough to specify the data layout string.