[PATCH] D19013: [DivergenceAnalysis] Treat PHI with incoming undef as constant

[Nicolai Hähnle via llvm-commits]

nhaehnle added a comment.

It turns out that this change manages to lead to the same assertion in test/CodeGen/AMDGPU/si-spill-cf.ll, which previously didn't assert only through sheer luck as far as I can tell.

So this commit should come after http://reviews.llvm.org/D19018, which implements the more thorough and robust fix for this problem that I had originally written.


http://reviews.llvm.org/D19013