[MemorySSA] Add SkipSelfWalker.

Summary: Add implementation of SkipSelfWalker.

Reviewers: george.burgess.iv

Subscribers: sanjoy, jlebar, Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D56285

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350561 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed