 OK it is not the same, bisected this to
0e9cdedd2e3943bdb7f3543a3508b883b167e427

 radeon/llvm: enable unsafe math for graphics shaders

 This optimization looks like should be disabled for graphic too on 32bit, but
will slow down things a little of course because it will render proper :D ...
at least guessing should be disabled for 32bit only  until sameone approve it
happens on 64bit mesa/software too.

 Ha, this one looks like good potentional candidate who made those GTT_WC
issues on 32bit, need to recheck that...