https://bugs.freedesktop.org/show_bug.cgi?id=88879
--- Comment #4 from Arek Ruśniak arek.rusi@gmail.com --- Maybe it wasn't clearly enough, it looks like llvm regression.
Radeonsi doesn't even support shader5.
Could you try if UH4 works for you with high/ultra(without override GL4)? And what revision of llvm do you use?