https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113233
--- Comment #6 from Yang Yujie <yangyujie at loongson dot cn> ---
(In reply to Xi Ruoyao from comment #4)
> (In reply to Jan Hubicka from comment #3)
> > > Confirm. But option save/restore has been always implemented:
> > >
> > > .section .gnu.lto_.opts,"",@progbits
> > > .ascii "'-fno-openmp' '-fno-openacc' '-fno-pie' '-fcf-protection"
> > > .ascii "=none' '-mabi=lp64d' '-march=loongarch64' '-mfpu=64' '-m"
> > > .ascii "simd=lasx' '-mcmodel=normal' '-mtune=loongarch64' '-flto"
> > > .ascii "'\000"
> > >
> > > So -msimd=lasx is correctly recorded. Not sure why it does not work.
> >
> > With LTO we need to mix code compiled with different sets of options.
> > For this reason we imply for every function defition and optimization
> > and target attribute which record the flags. So it seems target
> > attribute is likely broken for this flag.
>
> Target attribute is not implemented for LoongArch. And I don't think it's a
> good idea to implement it in stage 3.
Yes, target attribute may have to wait. But save/restore can be implemented
without target attributes of functions. By marking options as "Save" in .opt
or implementing custom TARGET_OPTION_{SAVE,RESTORE} hooks, we can stream the
target configuration (which may come from the command line / the target
attributes / #pragma GCC target) into the per-function LTO bytecode, so that
lto1 can pick up and use them later when generating code for each function.
