Keep DAA! (was Re: 8086 bugs)

[Chuck Guzis]

On 12/11/2005 at 3:28 PM Jim Leonard wrote:

>I spouted forth:
>> Mind you, I'm not even a fan of XLAT, as a simple indexed load is
>probably
>> faster on the Pentium-class machines.  

And Jim Leonard replied:

>Oh it is, by far.  But I love XLAT for 8088-class programming.

Often, when we're given an instruction or any other resource, we attempt to
incorporate it into a solution automatically.  Thus, if I'm doing BCD
addition, my thought is that DAA must be part of the answer, since it's in
the instruction set and it MUST be there for just such a purpose.

It's also true that we use what we're used to.  I cannot claim to have ever
used a CMPXCHG instruction, although it seems as if it might have some real
use--it just never entered my mind to use it.

Cheers,
Chuck