[v13,04/26] libstdc++: Optimize std::is_volatile compilation performance
Commit Message
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(+)
@@ -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);