--- Ramon van Handel <[EMAIL PROTECTED]> wrote:
> > I modified the instruction virtualization map,
> and marked
> > 'NOP' for virtualization. The following code
> sequence:
> >
> > _start:
> > clc
> > stc
> > nop
> > hlt
> >
> > ... caused the monitor to trap out at:
> >
> > Current instruction:
> > 000B.00100002 90 nop
>
> I may be stupid here, but *why* ? Nop doesn't trap
> and isn't harmful, so
> what's the point of virtualising it ? I don't get
> it.
>
> -- Ramon
Isn't nop often used in branching? That would be a
good reson to virtualize it!! Also, if something is
just iding until a hardware clock runs out we don't
want it to just be sitting there eating up cpu cycles
that could be used elsewhere--so why not trap "nop"
and thus allow the clock cycles to be put to good use
while redirecting any wait states into a virtual
hardware timer inside of the monitor? Just sounded
like a good idea to me ;-) !
Drew Northup, N1XIM
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