[stella] Re: It's all coming back...

Subject: [stella] Re: It's all coming back...
From: "Andrew Davie" <adavie@xxxxxxxxxxxxxxxxx>
Date: Wed, 6 May 1998 23:58:25 +1000
> If I were really cutting corners, I'd make sure that the
>value variable already was a multiple of two, and then it would be...
>
>    ldx value
>    lda jumptable,x
>    pha
>    lda jumptable+1,x
>    pha
>    rts


A better way, keeping the value as a non-multiple of two...

    ldx value
    lda jumpablelow,x
    pha
    lda jumptablehigh,x
    pha
    rts

That is, keep the jump vectors in two byte tables (high and low) instead of
words in a single table.  That way, you can just plug this into your
original code, save yourself both cycles AND bytes - which is what its all
about :)

Enjoy
A





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