[v14,15/40] libstdc++: Optimize is_member_pointer trait performance
Commit Message
This patch optimizes the performance of the is_member_pointer trait
by dispatching to the new __is_member_pointer built-in trait.
libstdc++-v3/ChangeLog:
* include/std/type_traits (is_member_pointer): Use __is_member_pointer
built-in trait.
(is_member_pointer_v): Likewise.
Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org>
---
libstdc++-v3/include/std/type_traits | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
@@ -716,6 +716,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
struct is_compound
: public __not_<is_fundamental<_Tp>>::type { };
+ /// is_member_pointer
+#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_member_pointer)
+ template<typename _Tp>
+ struct is_member_pointer
+ : public __bool_constant<__is_member_pointer(_Tp)>
+ { };
+#else
/// @cond undocumented
template<typename _Tp>
struct __is_member_pointer_helper
@@ -726,11 +733,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
: public true_type { };
/// @endcond
- /// is_member_pointer
template<typename _Tp>
struct is_member_pointer
: public __is_member_pointer_helper<__remove_cv_t<_Tp>>::type
{ };
+#endif
template<typename, typename>
struct is_same;
@@ -3242,8 +3249,14 @@ template <typename _Tp>
inline constexpr bool is_scalar_v = is_scalar<_Tp>::value;
template <typename _Tp>
inline constexpr bool is_compound_v = is_compound<_Tp>::value;
+
+#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_member_pointer)
+template <typename _Tp>
+ inline constexpr bool is_member_pointer_v = __is_member_pointer(_Tp);
+#else
template <typename _Tp>
inline constexpr bool is_member_pointer_v = is_member_pointer<_Tp>::value;
+#endif
#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_const)
template <typename _Tp>