[v13,04/26] libstdc++: Optimize std::is_volatile compilation performance

Message ID 20240221093616.4001742-4-kmatsui@gcc.gnu.org
State New
Headers
Series [v13,01/26] c++: Implement __is_const built-in trait |

Commit Message

Ken Matsui Feb. 21, 2024, 9:35 a.m. UTC
  This patch optimizes the compilation performance of std::is_volatile
by dispatching to the new __is_volatile built-in trait.

libstdc++-v3/ChangeLog:

	* include/std/type_traits (is_volatile): Use __is_volatile
	built-in trait.
	(is_volatile_v): Likewise.

Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org>
---
 libstdc++-v3/include/std/type_traits | 12 ++++++++++++
 1 file changed, 12 insertions(+)
  

Patch

diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
index 6e9ebfb8a18..60cd22b6f15 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -851,6 +851,12 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #endif
 
   /// is_volatile
+#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_volatile)
+  template<typename _Tp>
+    struct is_volatile
+    : public __bool_constant<__is_volatile(_Tp)>
+    { };
+#else
   template<typename>
     struct is_volatile
     : public false_type { };
@@ -858,6 +864,7 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
   template<typename _Tp>
     struct is_volatile<_Tp volatile>
     : public true_type { };
+#endif
 
   /// is_trivial
   template<typename _Tp>
@@ -3356,10 +3363,15 @@  template <typename _Tp>
   inline constexpr bool is_function_v<_Tp&&> = false;
 #endif
 
+#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_volatile)
+template <typename _Tp>
+  inline constexpr bool is_volatile_v = __is_volatile(_Tp);
+#else
 template <typename _Tp>
   inline constexpr bool is_volatile_v = false;
 template <typename _Tp>
   inline constexpr bool is_volatile_v<volatile _Tp> = true;
+#endif
 
 template <typename _Tp>
   inline constexpr bool is_trivial_v = __is_trivial(_Tp);