Ping for __is_reference built-in. Sincerely, Ken Matsui
On Wed, Jul 12, 2023 at 7:56 PM Ken Matsui <kmat...@cs.washington.edu> wrote: > > Hi, > > Here is the benchmark result for is_reference: > > https://github.com/ken-matsui/gcc-benches/blob/main/is_reference.md#wed-jul-12-074702-pm-pdt-2023 > > Time: -8.15593% > Peak Memory Usage: -4.48408% > Total Memory Usage: -8.03783% > > Sincerely, > Ken Matsui > > On Wed, Jul 12, 2023 at 7:39 PM Ken Matsui <kmat...@gcc.gnu.org> wrote: > > > > This patch gets std::is_reference to dispatch to new built-in trait > > __is_reference. > > > > libstdc++-v3/ChangeLog: > > > > * include/std/type_traits (is_reference): Use __is_reference > > built-in > > trait. > > (is_reference_v): Likewise. > > > > Signed-off-by: Ken Matsui <kmat...@gcc.gnu.org> > > --- > > libstdc++-v3/include/std/type_traits | 14 ++++++++++++++ > > 1 file changed, 14 insertions(+) > > > > diff --git a/libstdc++-v3/include/std/type_traits > > b/libstdc++-v3/include/std/type_traits > > index 0e7a9c9c7f3..2a14df7e5f9 100644 > > --- a/libstdc++-v3/include/std/type_traits > > +++ b/libstdc++-v3/include/std/type_traits > > @@ -639,6 +639,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION > > // Composite type categories. > > > > /// is_reference > > +#if __has_builtin(__is_reference) > > + template<typename _Tp> > > + struct is_reference > > + : public __bool_constant<__is_reference(_Tp)> > > + { }; > > +#else > > template<typename _Tp> > > struct is_reference > > : public false_type > > @@ -653,6 +659,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION > > struct is_reference<_Tp&&> > > : public true_type > > { }; > > +#endif > > > > /// is_arithmetic > > template<typename _Tp> > > @@ -3192,12 +3199,19 @@ template <typename _Tp> > > inline constexpr bool is_class_v = __is_class(_Tp); > > template <typename _Tp> > > inline constexpr bool is_function_v = is_function<_Tp>::value; > > + > > +#if __has_builtin(__is_reference) > > +template <typename _Tp> > > + inline constexpr bool is_reference_v = __is_reference(_Tp); > > +#else > > template <typename _Tp> > > inline constexpr bool is_reference_v = false; > > template <typename _Tp> > > inline constexpr bool is_reference_v<_Tp&> = true; > > template <typename _Tp> > > inline constexpr bool is_reference_v<_Tp&&> = true; > > +#endif > > + > > template <typename _Tp> > > inline constexpr bool is_arithmetic_v = is_arithmetic<_Tp>::value; > > template <typename _Tp> > > -- > > 2.41.0 > >
