[Bug target/59401] [SH] GBR addressing mode optimization produces wrong code
olegendo at gcc dot gnu.org
Wed Oct 15 13:45:00 GMT 2014
--- Comment #11 from Oleg Endo <olegendo at gcc dot gnu.org> ---
Created attachment 33723
Make GBR call preserved by default
(In reply to Oleg Endo from comment #10)
> (In reply to Kazumoto Kojima from comment #9)
> > (In reply to Oleg Endo from comment #8)
> > > change the
> > > value for gbr in sh.h CALL_USED_REGISTERS from '1' to '0' and confirm that
> > > everything is still OK?
> > The comment and document about CALL_USED_REGISTERS say that it must be
> > a superset of FIXED_REGISTERS. CALL_REALLY_USED_REGISTERS might be
> > a macro for that purpose.
> Right. In this case it's probably better to do it in
> sh_conditional_register_usage. It would be nice if '-fcall-saved-gbr' and
> '-fcall-used-gbr' still remained functional afterwards ... I'll give it a
sh_conditional_register_usage is invoked after the -fcall-*-* options are
processed. Defining the CALL_REALLY_USED_REGISTERS macro with the default
values works as expected, i.e. -fcall-used-gbr still works.
Kaz, could you please add the attached patch to your test run?
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