Re: [hatari-devel] Movem and cycles

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 19/01/2017 à 22:31, Laurent Sallafranque a écrit :
> Hi,
>
> A question about movem.
>
> Movem is a very frequent instruction on falcon true color, used very often.
[...]

> Again, it seems to count only 12 cycles.
>
> Isn't there a quick fix to count all the memory access time ?
>
> I know hatari 68030 is not accurate, but it'd be better is cycles where
> at least close to their nominal value, no ?
>
> With my latest code, I've got 2 VBLs difference between hatari and real
> Falcon.

Hi

for now, only 68030 in CE will count cycles for instructions with non 
fixed cycles count.

Toni, do you think it would be possible to extend gencpu and to define 
"using_simple_cycles = 1" for cpu id 20 and 22, maybe 32 too ? (as it's 
the case for id 12 and 68000 in prefetch mode).

It could give some extra accuracy when CE mode is not needed for movem, 
bit shift, muls/divs

Just adding "using_simple_cycles = 1;" is not enough at the moment 
because in that case gencpu checks for "using_prefetch" and not for 
"using_prefetch_020", but maybe adding this would be not to invasive ?

Nicolas