[PATCH v26 13/13] libstdc++: Optimize std::is_nothrow_invocable compilation performance

[Jonathan Wakely]

On 11/05/24 02:01 -0700, Ken Matsui wrote:
>This patch optimizes the compilation performance of
>std::is_nothrow_invocable by dispatching to the new
>__is_nothrow_invocable built-in trait.

OK, thanks.

>libstdc++-v3/ChangeLog:
>
>	* include/std/type_traits (is_nothrow_invocable): Use
>	__is_nothrow_invocable built-in trait.
>	* testsuite/20_util/is_nothrow_invocable/incomplete_args_neg.cc:
>	Handle the new error from __is_nothrow_invocable.
>	* testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc:
>	Likewise.
>
>Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org>
>---
> libstdc++-v3/include/std/type_traits                          | 4 ++++
> .../20_util/is_nothrow_invocable/incomplete_args_neg.cc       | 1 +
> .../testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc  | 1 +
> 3 files changed, 6 insertions(+)
>
>diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
>index 502032787bd..a046560c178 100644
>--- a/libstdc++-v3/include/std/type_traits
>+++ b/libstdc++-v3/include/std/type_traits
>@@ -3269,8 +3269,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>   /// std::is_nothrow_invocable
>   template<typename _Fn, typename... _ArgTypes>
>     struct is_nothrow_invocable
>+#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_nothrow_invocable)
>+    : public __bool_constant<__is_nothrow_invocable(_Fn, _ArgTypes...)>
>+#else
>     : __and_<__is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, void>,
> 	     __call_is_nothrow_<_Fn, _ArgTypes...>>::type
>+#endif
>     {
>       static_assert(std::__is_complete_or_unbounded(__type_identity<_Fn>{}),
> 	"_Fn must be a complete class or an unbounded array");
>diff --git a/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_args_neg.cc b/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_args_neg.cc
>index 3c225883eaf..3f8542dd366 100644
>--- a/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_args_neg.cc
>+++ b/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_args_neg.cc
>@@ -18,6 +18,7 @@
> // <http://www.gnu.org/licenses/>.
>
> // { dg-error "must be a complete class" "" { target *-*-* } 0 }
>+// { dg-prune-output "invalid use of incomplete type" }
>
> #include <type_traits>
>
>diff --git a/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc b/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc
>index 5a728bfa03b..d3bdf08448b 100644
>--- a/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc
>+++ b/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc
>@@ -18,6 +18,7 @@
> // <http://www.gnu.org/licenses/>.
>
> // { dg-error "must be a complete class" "" { target *-*-* } 0 }
>+// { dg-prune-output "invalid use of incomplete type" }
>
> #include <type_traits>
>
>-- 
>2.44.0
>