Hi!
After the recent Tom Stellard's commit to LLVM StructurizeCFG, the Blender kernel does not crash Mesa's R600 shader compiler anymore.
So it seems it should be possible to compile Blender kernel under it.
But first it complains about line 803 in kernel_shader.h
sd->flag = bsdf_diffuse_setup(&sd->closure);
which should be
sd->flag = bsdf_diffuse_setup(sd->closure);
(it's probably another part of what I reported in T41912...)
And after correcting this problem it fails with "unsupported call to function fabsf in kernel_ocl_path_trace" - one fabsf() call gets into the IR nevertheless fabsf() is a macro... somewhere near exit from kernel_path_integrate()... It's very strange because the IR looks like fabsf(fabsf(v.x)+fabsf(v.y)+fabsf(v.z)) != 0 and the "outer" fabsf in this expression is not substituted... O_o.