Re: [hatari-devel] 68030 cycle timings for 64bit div/mul

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 29/01/2013 17:05, Douglas Little a écrit :
> Hi Nicolas,
>
>     it's not handled. 64 bit mul/div are more complex than the 68000
>     equivalent and so far no one has reverse engineered those
>     instructions to "guess" the algorithm and its timing.
>
>
> Ok I see. So what is the expected behaviour for a program using these
> instructions in Hatari?
>
> BadMood uses these instructions and I have not studied any diverse
> effects from using them (timing, accuracy, invalid results....). It just
> appeared to work....
>
> Thanks,
> D.

If I recall correctly, the number of cycles is the average of the best 
case / worst case given in the 68030 documentation.

This will certainly gives you different results from a real Falcon, but 
there's not much that can be done on this now.

Nicolas