Keep DAA! (was Re: 8086 bugs)

[Jim Leonard]

Fred Cisin wrote:
>>If DAA were slow, I'd say ditch it.  But DAA is only 4 cycles and according to
>>my real-world 8088 timings (slow night tonight), the DAA approach is only just
>>a hair slower than the XLAT method.
>>So I guess there *is* a need for DAA ;-)
> 
> 
> Howzbout:
> AND AL, 0Fh
> DAA
> ADD AL, 0F0h
> ADC AL, 40h
> 
> or:
> 
> AND AL, 0Fh
> ADD AL, 0
> ADC AL,28h
> DAA

Both are the same speed and size, and quick timing shows that they are now the 
same speed as the XLAT method.  (I assume that's what you were asking)
-- 
Jim Leonard (trixter at oldskool.org)                    http://www.oldskool.org/
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