For teaching and demonstration purposes it would be cool to have emulated fp64
arithmetic on low-end Evergreen and Northern Islands chips which don't support
it (e.g. Caicos). However slow it might end up being, it would be really useful
to have it at least for teaching GPU computing.

glennk, iive and others discussed this in #radeon on 2015-09-13:
http://people.freedesktop.org/~cbrill/dri-log/?channel=radeon&highlight_names=&date=2015-09-13