Re: Fwd: Re: [hatari-devel] Re: [hatari-users] DSP emulation - MPY #immediate

[Eero Tamminen <oak@xxxxxxxxxxxxxx>]

Hi,

On maanantai 28 tammikuu 2013, Douglas Little wrote:
> Please find the requested trace attached!
> 
> On 28 January 2013 18:53, Laurent Sallafranque
> <laurent.sallafranque@xxxxxxx
> 
> > wrote:
> >  Doug,
> > 
> > Would you please do the following :
> > 
> > In the debugger :
> >  b pc=text:once
> > 
> > start your program

Thanks, it seems pretty clear that profiler gets
DSP cycles for the previous instruction.

This is because debugger is called before DSP code is
executed, in dsp.c:
----------
        if (unlikely(bDspDebugging)) {
                while (save_cycles > 0)
                {
                        DebugDsp_Check();
                        dsp56k_execute_instruction();
                        save_cycles -= dsp_core.instr_cycle;
                }
        } else {
----------

Next question is should the order of DSP instruction
execution and debugger hook be inverted.

Then DSP breakpoints would hit one instruction later, after
the instruction at given PC address has already been executed.

If latter isn't desirable, I need to delay cycle information
storing by one instruction.


	- Eero