[LoopInterchange] Make isProfitableForVectorization slightly more conservative.
After D43236, we started interchanging loops with empty dependence
matrices. In isProfitableForVectorization, we try to determine if
interchanging makes the loop dependences more friendly to the
vectorizer. If there are no dependences, we should not interchange,
based on that heuristic.
Reviewers: efriedma, mcrosier, karthikthecool, blitz.opensource
Reviewed By: mcrosier
Differential Revision: https://reviews.llvm.org/D45208
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@330738 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed