Re: [hatari-devel] Little disassembler bug ?

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 07/10/2012 21:57, Laurent Sallafranque a écrit :
> Hi Eero,
>
> I think Nicolas wanted to keep the new core Winuae disassembler, but I
> don't remember why.
>
> Nicolas ?

Hello

having the original winuae disassembler available can be useful for 
debugging purpose, especially with all the changes going on recently in 
the 68030+mmu.

But even if they sometimes use slightly different notation, they should 
give the same result, else a bug can be hidding somewhere. Especially in 
that case, it seems something was broken in the winuae disassembler 
recently (or maybe it was already broken in winuae)

Nicolas

> Le 07/10/2012 21:41, Eero Tamminen a écrit :
> > Hi,
> >
> > On sunnuntai 07 lokakuu 2012, Laurent Sallafranque wrote:
> > > While debugging something, I've noticed what I think is a little bug in
> > > desassembler :
> > >
> > > In my code, I have
> > >    mulu.l        d1,d0
> > >
> > > With the (d) command, I read the correct opcode :
> > >    $05d9a4 : 4c01 0000                            mulu.l    d1,d0
> > >
> > >
> > > When I activate cpu_disasm, I read :
> > >    0005D9A4 4c01 0000                MULL.L #$0000,D1
> > >
> > > The result of the mul seems correct in d0.l after the mulu.l,
> > > but the disassembled instruction seems wrong.
> > I assume this is with the WinUAE CPU core.
> >
> > You need to change lines like this in its newcpu.c file:
> >    m68k_disasm(stderr, m68k_getpc (), NULL, 1);
> >
> > To look like this:
> >    Disasm(stderr, m68k_getpc (), NULL, 1, DISASM_ENGINE_EXT);
> >
> > I.e. instead of using the CPU core builtin disassembler,
> > use the disassembler contributed by Markus Fritze as
> > the old UAE core nowadays does.
> >
> > Or is there some good reason why WinUAE core is using
> > its own disassembler?
> >
> >
> >     - Eero