MachineCopyPropagation: Catch copies of the form A<-B;A<-B

Differential Revision: http://reviews.llvm.org/D17475

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261966 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed