9a7e19b8f2
It's possible for vector op legalization to generate a shuffle. If that happens we should give a chance for DAG combine to combine that with a build_vector input. I also fixed a bug in combineShuffleOfScalars that was considering the number of uses on a undef input to a shuffle. We don't care how many times undef is used. Differential Revision: https://reviews.llvm.org/D54283 llvm-svn: 346530