On Tue, Sep 26, 2023 at 9:50 AM Jakub Jelinek <ja...@redhat.com> wrote: > > On Tue, Sep 26, 2023 at 09:34:15AM +0200, Richard Biener wrote: > > On Mon, Sep 25, 2023 at 8:25 PM Tobias Burnus <tob...@codesourcery.com> > > wrote: > > > > > > I stumbled over this during the ARM64 talk at the cauldron as they > > > consider using -fopenmp-simd by default. > > > > Ah, forgot to ask during the talk - isn't __attribute__((simd(..))) exactly > > to > > avoid the need for -fopenmp-simd? > > Yes. Though, -fopenmp-simd can do slightly more than that, > #pragma GCC ivdep equivalent on various loops is the other important part > (though for both simd attribute and ivdep pragma the OpenMP counterparts > are significantly more flexible, in the declare simd case one can specify > certain arguments should be linear (with various variants for > references)/uniform, simd construct can specify not just everything is > independent or not, but how many consecutive iterations must be independent, > can specify reductions etc., preferred vectorization factors, ...). > Though, I don't think it is a good idea to enable -fopenmp-simd by default.
Yeah, writing invalid OMP simd pragmas (syntactically or semantically) shouldn't be causing problems when not using -fopenmp-simd but would if that's the default. Richard. > > Jakub >
