The SLP Vectorizer works across basic blocks. Update the docs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184973 91177308-0d34-0410-b5e6-96231b3b80d8
[APFloat] Removed debugging cruft that snuck in.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184974 91177308-0d34-0410-b5e6-96231b3b80d8