Need to merge 2813acb

[kaz7]

@simoll -san, can you merge 2813acb? Merging this causes compile error.

Previously, we modify llvm/include/llvm/IR/PatternMatch to use not only match but also match_context. However, this patch adds undef_match newly. We again need to modify this undef_match to work with match_context well.

I've merged up to dd68942 which is one predecessor of 2813acb.

[simoll]

Alright. Fixed in ff3058e

[kaz7]

Merged by #53.