[SCEV] Commute sign extends through nsw additions

Summary: Depends on D13613.

Reviewers: atrick, hfinkel, reames, nlewycky

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13685

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251049 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed