Re: [rfc] Displaced stepping with wrong entry point address

Ulrich Weigand
2008-09-04T20:31:41Z

Daniel Jacobowitz wrote:
> On Thu, Sep 04, 2008 at 09:28:06PM +0200, Ulrich Weigand wrote:
> > > If SPU ever did support displaced stepping (not that this would be
> > > terribly useful, but consider some other multi-architecture case),
> > > would this be wrong for the SPU side code?
> >
> > Yes, of course -- we have different address spaces here, and we need
> > to find a location within the address space of the current thread where
> > to place the displaced instruction. No single address would work for
> > both PowerPC and SPU code in a combined application.
> >
> > But I guess SPU could always install its own callback to handle those
> > special cases ... (just as we install the ON_STACK dummy call location
> > method because the AT_ENTRY method doesn't work for combined applications.)
>
> In that case, maybe this is really specific to PowerPC; it sounds like
> it won't work for any general multi-architecture target.

OK, agreed. I'll make this specific to PowerPC as part of the Cell
multi-arch support (b.t.w. I'll be posting an initial patch set for
that really soon now, I hope ...)