Re: Fastcode UpperCase B&V 0.2

From: Les Pawelczyk (les_at_pixelpointpos_dot_com)
Date: 10/01/03 

Date: Wed, 1 Oct 2003 12:31:45 -0400

(It's so simple, I don't know why it hasn't been done before)
> :-
>
> {Convert character in AL to Uppercase}
> sub al, 'a'
> sub al, 26
> sbb ecx, ecx
> and cl, -$20
> add al, 'a'+26
> add al, cl

I've done something similar before:

 cmp al, 'z'
 seta ah
 cmp al, 'a'
 adc ah, $1f
 or ah, $df
 and al, ah

I have abandoned above approach for lookup table solution. But your example
gives me some SSE ideas since SBB functionality can be replaced by PCMPGTB.

Les.

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