https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77776
--- Comment #9 from Matthias Kretz <kretz at kde dot org> --- (In reply to emsr from comment #7) > What does this do? > > auto __hi_exp = > __hi & simd<_T, _Abi>(std::numeric_limits<_T>::infinity()); // no error component-wise bitwise and of __hi and +inf. Or in other words, it sets all sign bits and mantissa bits to 0. Consequently `__hi / __hi_exp` returns __hi with the exponent bits set to 0x3f8 (float) / 0x3ff (double) and the mantissa bits unchanged. > Sorry, I have no simd knowlege yet. It's a very simple idea: - simd<T> holds simd<T>::size() many values of type T. - All operators/operations act component-wise. See Section 9 in wg21.link/N4793 for the last WD of the TS. > Anyway, doesn't the large scale risk overflow if a, b are large? I guess I'm > lost. It basically has the same underflow risks as your implementation does, and no risk of overflow.
