Constant propagation after hitting assume(cmp) bugfix

Last time code run into assertion `BBE.isSingleEdge()` in
lib/IR/Dominators.cpp:200.

http://reviews.llvm.org/D12170

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@246244 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed