Re: A92: Constants and immediate values + movem
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Re: A92: Constants and immediate values + movem
On Mon, 18 Aug 1997, Niklas Brunlid wrote:
>
> A friend told me he'd seen a site with just these kind of tips for using
> other mnemonics just like this. You wouldn't know where that is?
>
> >A good 68000 assembler will automatically convert the LEA into an ADDQ
> >when it is possible (if the offset is 1 to 8) or to a SUBQ (if the offset
> >is -1 to -8). However, A68K is not that advanced. A68K does not change
> >between ADDQ and LEA.
>
> Does A68K substitute anything? ADD/ADDQ/ADDI?
>
I hope it doesn't. IMHO assemblers shouldn't make such replacements
unless specifically asked to (with an optimizer flag or something).
Optimization tips for 68k has been around ever since people started
hacking the Amiga, but I cant come up with a specific siter wheree
they can be found. Try searching on Aminet for doucmentation. There's
one doc that was really great - called "How to Code" which I think
contained a lot of optimization tips, among other things.
// Jonas Minnberg
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