[gcc r14-6631] libstdc++: Optimize std::is_object compilation performance

[gcc r14-6631] libstdc++: Optimize std::is_object compilation performance

[Ken Matsui]

https://gcc.gnu.org/g:4b111013654e745e8d73bd9614a15efbfd19ae8c

commit r14-6631-g4b111013654e745e8d73bd9614a15efbfd19ae8c
Author: Ken Matsui <kmatsui@gcc.gnu.org>
Date:   Thu Mar 30 02:13:49 2023 -0700

    libstdc++: Optimize std::is_object compilation performance
    
    This patch optimizes the compilation performance of std::is_object
    by dispatching to the new __is_object built-in trait.
    
    libstdc++-v3/ChangeLog:
            * include/std/type_traits (is_object): Use __is_object built-in
            trait.
            (is_object_v): Likewise.
    
    Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org>
    Reviewed-by: Jonathan Wakely <jwakely@redhat.com>

Diff:
---
 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 b6d0441129b..2979d79a801 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -725,11 +725,18 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     { };
 
   /// is_object
+#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_object)
+  template<typename _Tp>
+    struct is_object
+    : public __bool_constant<__is_object(_Tp)>
+    { };
+#else
   template<typename _Tp>
     struct is_object
     : public __not_<__or_<is_function<_Tp>, is_reference<_Tp>,
                           is_void<_Tp>>>::type
     { };
+#endif
 
   template<typename>
     struct is_member_pointer;
@@ -3280,8 +3287,15 @@ template <typename _Tp>
   inline constexpr bool is_arithmetic_v = is_arithmetic<_Tp>::value;
 template <typename _Tp>
   inline constexpr bool is_fundamental_v = is_fundamental<_Tp>::value;
+
+#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_object)
+template <typename _Tp>
+  inline constexpr bool is_object_v = __is_object(_Tp);
+#else
 template <typename _Tp>
   inline constexpr bool is_object_v = is_object<_Tp>::value;
+#endif
+
 template <typename _Tp>
   inline constexpr bool is_scalar_v = is_scalar<_Tp>::value;
 template <typename _Tp>