On Mar 15, 2013, at 11:43, John Ehrman wrote:
> One reason for the Assembler's not having implemented a fuller set of
> extended branch mnemonics is that once the original ("incomplete") set
> wasprovided, many users implemented their own macro-based extensions.
>
> Given the decades-long lack of a mechanism to choose between a set of
> built-in assembler mnemonics and a wide variety of user-implemented
> mnemonics (not all of which were the same) it seemed safest to stay with
> the original set. It could be very risky for the assembler to provide
> built-in extended mnemonics that had slightly different branch masks from
> those a customer was already using, because programs could behave very
> differently with no warning or other indication.
>
Partly for that reason, and partly for mere legibility, I'd
recommend a more structured op code field:
Something such as BR(NE)
Rather than: BNER
-- gil
