(In reply to comment #1)
> (In reply to comment #1)
> > I tried finding a working commit going back with mesa, but I get to a point
> > where llvm renders nothing at all with anything using current llvm svn.
> 
> There have been incompatible changes to the interface between r600g and the
> LLVM R600 backend, so you'd probably need a matching LLVM snapshot. The Git
> mirror at http://llvm.org/git/llvm.git might be helpful for this.

OK, it is in llvm. Bisecting with mesa on head comes up with -

fd49dac48fee6da580157515dec55ed2f2d8f2b3 is the first bad commit
commit fd49dac48fee6da580157515dec55ed2f2d8f2b3
Author: Vincent Lejeune <vljn@ovi.com>
Date:   Mon Mar 11 18:15:06 2013 +0000

    R600: Fix JUMP handling so that MachineInstr verification can occur

    This allows R600 Target to use the newly created -verify-misched llc flag

    git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176819
91177308-0d34-0410-b5e6-96231b3b80d8