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Date   : Thu, 10 Jun 1993 13:34:08 BST
From   : ajcd@...
Subject: m/c optimisations

From: I Stephenson <ian@...>
>Performance isn't so bad as we can write the interpretter as
>.loop
>LDX pc
>INC pc
>JSR (table,x) \I think this is a bad instruction!
>JMP loop

JSR (table,X) is indeed a non-existant instruction. On the 65C02 there is a
JMP (abs,X) instruction, so you could write

        ...
        JSR dispatch
        ...
.dispatch       JMP (table,X)

On the 6502, you have to do something like:

.dispatch LDA low,X
        STA addr
        LDA high,X
        STA addr
        JMP (addr)

a.
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