The original commit was reverted because of a buildbot problem with LazyCallGraph::SCC handling (not related to the OptBisect handling). Differential Revision: http://reviews.llvm.org/D19172 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267231 91177308-0d34-0410-b5e6-96231b3b80d8