Re: [hatari-devel] WinUAE and 030 cache hits/misses?

[Eero Tamminen <oak@xxxxxxxxxxxxxx>]

Hi,

On lauantai 26 tammikuu 2013, Laurent Sallafranque wrote:
> The patch seems OK to me.

I commited it already a bit earlier.


> I've done a quick test with it for cache/non cache timings,
> but there are still things to fix before this.
> It didn't change many things as I first expected.

I noticed that per-instruction cycle information is zero
just with the WinUAE "exact" CPU model.  If I use
"--machine falcon --cpu-exact false", I do get cycle
information.

I.e. with "cycle exact" CPU model one can get just cache miss
information, and with "non-cycle-exact" CPU model one gets
just the cycles information (but it's supposedly non-exact).


By "cycles information" I mean values of "CurrentInstrCycles"
and "nWaitStateCycles" variables at the time do_specialties()
is called in CPU core main loop.


Which of the newcpu.c *run() "main loop" functions are used when
selecting cycle-exact and non-cycle-exact CPU mode with WinUAE?


	- Eero

> Still some work to do ;)
> 
> Thanks Eero,
> 
> Best regards
> 
> Laurent
> 
> Le 24/01/2013 00:20, Eero Tamminen a écrit :
> > Hi,
> > 
> > On maanantai 21 tammikuu 2013, laurent.sallafranque@xxxxxxx wrote:
> >> If you add it, I can quickly improve the cycles counting by taking
> >> into account the hit/miss flag. I'm sure this would increase the
> >> quality of the approximative cycles computing I'm curently doing (and
> >> maybe let some timing critic programs run a bit better), especially
> >> the programs that deals with the DSP for music.
> > 
> > Attached is a preliminary patch for testing this, but I noticed some
> > wierd things with it:
> > 
> > * There can be 0-3 cache misses *per* instruction (prefetch), I'm
> > assuming
> > 
> >    this to mean that several instructions that were not in cache can
> >    get fetched with the same prefetch.  Comments on that?
> > 
> > * With WinUAE core, CPU instruction cycle counts are zero when debugger
> > 
> >    is called.   With old UAE core they're fine.  Are debugger calls in
> >    WinUAE in similar places as they are in old UAE CPU core?
> > 	
> > 	- Eero