Re: [hatari-devel] Re: Hatari debugging help with WinUAE CPU core

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 24/01/2014 22:55, Eero Tamminen a écrit :

> > maybe you could use "--exception_debug" instead ?
>
> That's way too long, it would make Hatari "--help" output too
> wide for 80 cols console.  If you want it changed, please suggest
> something more specific that's not longer than "--exceptions"
> (current option&  help already goes to 80 cols).
>
> Already existing --debug options has also very broad meaning,
> how I should rename that ?

Hello

Yes, '--debug' is not very self explanatory, especially as it has 
nothing to do with "debugging" directly, but more with breaking on "bus 
error" and "address error" (it's a historical option where emulation was 
less precise)

Maybe "--debug" could be removed, I doubt the change will affect many 
people.
Then it could be merged with "--exceptions" into "--debug-execpt", which 
would fit the 80 char column width :

  --run-vbls <x>          Exit after x VBLs
  --debug-execpt <mask>   xxxxx

Regarding this 80 columns limitation, do we still need it ? I don't 
think so, we could relax it a little up to 100 chars, nobody is running 
hatari from plain fixed 80x25 tty :)

Any console window can be resized in width to see more chars (and 80 
chars is really short, I doubt any user running hatari from a console 
has so short windows).
For example, take a look a "gcc --help", it goes to 115 column in my 
french locale settings.


> > if ( ( nr>=2 )&&  ( nr<=11)&&  ( ExceptionDebugMask ) )
> > 	DebugUI_Check_Interrupt_Mask ( nr );
>
> I'm assuming you're more worried about modifying existing code
> lines than adding single block of code there.  If that's true,
> does the attached patch look better?

It's shorter, but I'd like better something where all extra code/text 
goes into the *.c debug files :

if (ExceptionDebugMask && nr > 3 && nr < 9)
  DebugUI_Exceptions ( nr );

The CPU emulation part is really complex, sometimes hard to follow and 
the less "distraction" there is, the better it is, so I would prefer if 
inserted debug code could be limited to 2 lines : one "if" statement and 
one function call.

The other modifications in newcpu.c look ok to me, it's just the one at 
"@@ -1049,6 +1052,22 @@" that should be changed.


> And why there's debugger activation in Exception(),
> instead of in exception_debug() that's called from
> above listed functions (i.e. like it's done in old
> UAE CPU core)?
>
>
> (Exception handling there looks completely different, i.e. I don't
> think adding exception debugging there to affect merging in either
> direction.)

cpu/newcpu.c does not have the same logic has uae-cpu/newcpu.c, so I 
guess that when Laurent added changes to improve the falcon emulation, 
not all code in uae-cpu was merged into the new cpu core as some cpu 
structures are not the same and it's harder to backport the code.

Unfortunately, I don't have time to work on this now, so I think it will 
stay this way for a moment (unless someone with good cpu knowledge wants 
to change this without breaking everything :) ).

But in the end, as Doug asked for such exceptions mask to help debugging 
his code, if this new --debug-except is only present in the old cpu 
core, I'm afraid it won't be very useful to him, as the old core is not 
the recommended one for falcon emulation ?


Nicolas