Message ID | 20230708051137.63707-5-kmatsui@gcc.gnu.org |
---|---|
State | New |
Headers | show |
Series | c++, libstdc++: get std::is_object to dispatch to new built-in traits | expand |
On Sat, 8 Jul 2023 at 06:15, Ken Matsui via Libstdc++ <libstdc++@gcc.gnu.org> wrote: > > This patch gets std::is_function to dispatch to new built-in trait > __is_function. > > libstdc++-v3/ChangeLog: > > * include/std/type_traits (is_function): Use __is_function built-in > trait. > (is_function_v): Likewise. > > Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org> > --- > libstdc++-v3/include/std/type_traits | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits > index 2a14df7e5f9..954b57518de 100644 > --- a/libstdc++-v3/include/std/type_traits > +++ b/libstdc++-v3/include/std/type_traits > @@ -594,6 +594,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION > { }; > > /// is_function > +#if __has_builtin(__is_function) > + template<typename _Tp> > + struct is_function > + : public __bool_constant<__is_function(_Tp)> > + { }; > +#else > template<typename _Tp> > struct is_function > : public __bool_constant<!is_const<const _Tp>::value> { }; > @@ -605,6 +611,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION > template<typename _Tp> > struct is_function<_Tp&&> > : public false_type { }; > +#endif > > #define __cpp_lib_is_null_pointer 201309L > > @@ -3197,8 +3204,14 @@ template <typename _Tp> > inline constexpr bool is_union_v = __is_union(_Tp); > template <typename _Tp> > inline constexpr bool is_class_v = __is_class(_Tp); > + > +#if __has_builtin(__is_function) > +template <typename _Tp> > + inline constexpr bool is_function_v = __is_function(_Tp); > +#else > template <typename _Tp> > inline constexpr bool is_function_v = is_function<_Tp>::value; This fallback could be: template <typename _Tp> inline constexpr bool is_function_v = !is_const_v<const _Tp>; That would avoid instantiating std::is_function and std::is_const and std::integral_constant, which should be significant.
diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits index 2a14df7e5f9..954b57518de 100644 --- a/libstdc++-v3/include/std/type_traits +++ b/libstdc++-v3/include/std/type_traits @@ -594,6 +594,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { }; /// is_function +#if __has_builtin(__is_function) + template<typename _Tp> + struct is_function + : public __bool_constant<__is_function(_Tp)> + { }; +#else template<typename _Tp> struct is_function : public __bool_constant<!is_const<const _Tp>::value> { }; @@ -605,6 +611,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template<typename _Tp> struct is_function<_Tp&&> : public false_type { }; +#endif #define __cpp_lib_is_null_pointer 201309L @@ -3197,8 +3204,14 @@ template <typename _Tp> inline constexpr bool is_union_v = __is_union(_Tp); template <typename _Tp> inline constexpr bool is_class_v = __is_class(_Tp); + +#if __has_builtin(__is_function) +template <typename _Tp> + inline constexpr bool is_function_v = __is_function(_Tp); +#else template <typename _Tp> inline constexpr bool is_function_v = is_function<_Tp>::value; +#endif #if __has_builtin(__is_reference) template <typename _Tp>
This patch gets std::is_function to dispatch to new built-in trait __is_function. libstdc++-v3/ChangeLog: * include/std/type_traits (is_function): Use __is_function built-in trait. (is_function_v): Likewise. Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org> --- libstdc++-v3/include/std/type_traits | 13 +++++++++++++ 1 file changed, 13 insertions(+)