https://bugs.freedesktop.org/show_bug.cgi?id=65438
--- Comment #1 from Michel Dänzer michel@daenzer.net --- I can't reproduce this. Make sure your LLVM and Mesa snapshots are both up to date and built consistently.
If that doesn't help, can you isolate which LLVM change introduced the problem for you? The Git mirror at http://llvm.org/git/llvm.git might be useful for that.