Address space and pointer width

On the LLVM side, it seems that there is only one pointer type regardless the address space.
However, on clang side, function getPointerWidthV can be overloaded to specify different pointer widths for different address spaces.

Do you know what is the current state of this feature ? Are variable pointer widths fully supported from the frontend to the backend ?
If not fully supported, do you know if there is any intent to support it… or how difficult would it be to support it ?

Thank you !

Damien