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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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