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Re: [new-ra] "#if DENIS"
Denis Chertykov <denisc@overta.ru> writes:
> Michael Matz <matz@suse.de> writes:
>
> > Hi,
> >
> > On 15 Jul 2003, Denis Chertykov wrote:
> >
> > > Yes. This can introduces a few passes of allocation, but I havn't seen
> > > more than two, and code quality will be higher than after reload pass.
> > > Michael ! reload isn't so fast as you think.
> >
> > I don't think it's fast ;-) But I know that two additional but needless
> > allocator rounds also aren't exactly fast. Needless in the sense that
> > even without them reload wouldn't be needed (on my architecture).
>
> I remember that reload (reload on insns modified by allocator) was founded
> by me. After that I have realized assign_stack_slots and etc.
> I can't remembered why these reloads happened.
> Also I'm worried about register elimination. It's another one round of
> similar problems.
>
> > > > I made the appropriate changes to recog.c. While the new ra is running
> > > > spill pseudos are recognized as memory expressions (as offseted from the
> > > > frame or stack pointer, but with the real offset unknown).
> > >
> > > What happened if such pseudos will be colored ?
> >
> > The same what happens when the normal pseudos are colored. There is no
> > difference.
> >
> > > To which color such pseudos will be colored ?
> >
> > To one of those allowed by the constraints.
>
> You don't mark insns with spill-pseudos as ra_modified_insns.
> Such insns isn't rescanned and will have a wrong web->regclass field.
> So, spill-web can be colored to wrong color.
What do you thinnk about this ?
Denis.