metric is way off for these in general, and this works around
buggy code like that in PR1764. we'll see if there is a big
performance impact of this. If so, I'll revert it tomorrow.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43668 91177308-0d34-0410-b5e6-96231b3b80d8