Instead of aborting if not a case we can handle specially, break out and

Instead of aborting if not a case we can handle specially, break out and
let the generic code handle it.  This fixes CodeGen/Generic/2005-10-21-longlonggtu.ll on ppc.

also, reindent this code

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23874 91177308-0d34-0410-b5e6-96231b3b80d8