On Wed, Jul 14, 2021 at 2:39 PM Matthias Kretz <m.kretz@xxxxxx> wrote: > > On Wednesday, 14 July 2021 07:18:29 CEST Hongtao Liu via Gcc-help wrote: > > On Wed, Jul 14, 2021 at 1:15 PM Hongtao Liu <crazylht@xxxxxxxxx> wrote: > > > Hi: > > > The original problem was that some users wanted the cmdline option > > > > > > -ffast-math not to act on intrinsic production code. > > This sounds like the users want intrinsics to map *directly* to the Thanks for the reply. I think the users want the mixed usage of fast-math and no-fast-math. > corresponding instruction. If that's the case such users should use inline > assembly, IMHO. If you compile a TU with -ffast-math then *all* floating-point > operations are affected. Yes, more control over where to use fast-math and the > ability to mix fast-math and no-fast-math without risking ODR violations would > be great. But that's a larger issue, and one that would ideally be solved in > WG14/WG21. hmm, guess it would need a lot of work. > > FWIW, this is what I'd do, i.e. turn off fast-math for the function in > question: > https://godbolt.org/z/3cKq5hT1o > > -- > ────────────────────────────────────────────────────────────────────────── > Dr. Matthias Kretz https://mattkretz.github.io > GSI Helmholtz Centre for Heavy Ion Research https://gsi.de > std::experimental::simd https://github.com/VcDevel/std-simd > ────────────────────────────────────────────────────────────────────────── -- BR, Hongtao
