Return the first applicable encoding from general_encoding().
Return the first applicable encoding from general_encoding().

We'll arrange encoding lists such that the first suitable encoding is
the best choice for the legalizer. This is the most intuitive way of
generating the encodings.

After register allocation, we may choose a different encoding, but that
will require looking at the whole list.

sunfishcode/cretonne,stoklund/cretonne,sunfishcode/cretonne,stoklund/cretonne,stoklund/cretonne,sunfishcode/cretonne