Look at the end of the entry block for an invoke.

Look at the end of the entry block for an invoke.

The invoke could be at the end of the entry block. If it's the only one, then we
won't process all of the landingpad instructions correctly. This code is
currently ugly, but should be made much nicer once the new EH switch is thrown.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138397 91177308-0d34-0410-b5e6-96231b3b80d8