Re: [gcc r14-2455] riscv: Prepare backend for index registers

["Christoph Müllner" <christoph.muellner@vrull.eu>]

On Mon, Jul 17, 2023 at 9:31 AM Andrew Pinski <pinskia@gmail.com> wrote:
>
> On Sun, Jul 16, 2023 at 11:49 PM Christoph Müllner
> <christoph.muellner@vrull.eu> wrote:
> >
> > On Fri, Jul 14, 2023 at 12:28 PM Andreas Schwab <schwab@linux-m68k.org> wrote:
> > >
> > > Why didn't you test that?
> >
> > Thanks for reporting, and sorry for introducing this warning.
> >
> > I test all patches before sending them.
> > In the case of RISC-V backend patches, I build a 2-stage
> > cross-toolchain and run all regression tests for RV32 and RV64 (using
> > QEMU).
> > Testing is done with and without patches applied to identify regressions.
> >
> > The build process shows a lot of warnings. Therefore I did not
> > investigate finding a way to use -Werror.
> > This means that looking for compiler warnings is a manual step, and I
> > might miss one while scrolling through the logs.
>
> If you are building a cross compiler, and want to clean up warnings,
> first build a native compiler and then build the cross using that.

Ok, will adjust my workflow accordingly.

> Also maybe it is finding a way to do native bootstraps on riscv to do
> testing of patches rather than doing just cross builds when testing
> backend patches.
> Especially when I have found the GCC testsuite but the bootstrap is
> more likely to find backend issues and such.

Yes, using the patch-under-testing to build a toolchain can identify
issues that the testsuite can't find. I did that a couple of times in a
QEMU environment, but I prefer the cross-toolchain approach because
it is faster. For patches that have a bigger impact, I test the toolchain
with SPEC CPU 2017.

Thanks,
Christoph

>
> Thanks,
> Andrew
>
> >
> > Sorry for the inconvenience,
> > Christoph
> >
> >
> > >
> > > ../../gcc/config/riscv/riscv.cc: In function 'int riscv_regno_ok_for_index_p(int)':
> > > ../../gcc/config/riscv/riscv.cc:864:33: error: unused parameter 'regno' [-Werror=unused-parameter]
> > >   864 | riscv_regno_ok_for_index_p (int regno)
> > >       |                             ~~~~^~~~~
> > > cc1plus: all warnings being treated as errors
> > > make[3]: *** [Makefile:2499: riscv.o] Error 1
> > >
> > > --
> > > Andreas Schwab, schwab@linux-m68k.org
> > > GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
> > > "And now for something completely different."