Fix signed-unsigned comparison warning.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174387 91177308-0d34-0410-b5e6-96231b3b80d8
Fix comment formatting


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174388 91177308-0d34-0410-b5e6-96231b3b80d8