Fix the a / b ordering in some compares. Delete duplicate patterns.
Add a table explaining things. While I was cleaning this up, I managed
to confuse myself. The table helped sort that out.
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
e07248d2a8