If DoneMBB becomes empty it must have CC added to its live-in list, since it
will fall-through into EndMBB. This happens when the CLC loop does the
complete range.
Review: Ulrich Weigand
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@327834 91177308-0d34-0410-b5e6-96231b3b80d8