diff mbox series

[v14,26/26] libstdc++: Optimize std::is_nothrow_invocable compilation performance

Message ID 20240228192843.188979-27-kmatsui@gcc.gnu.org
State New
Headers show
Series Optimize more type traits | expand

Commit Message

Ken Matsui Feb. 28, 2024, 7:26 p.m. UTC
This patch optimizes the compilation performance of
std::is_nothrow_invocable by dispatching to the new
__is_nothrow_invocable built-in trait.

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(+)

Comments

Patrick Palka March 8, 2024, 5:22 p.m. UTC | #1
On Wed, 28 Feb 2024, 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.
> 
> 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 9af233bcc75..093d85a51a8 100644
> --- a/libstdc++-v3/include/std/type_traits
> +++ b/libstdc++-v3/include/std/type_traits
> @@ -3265,8 +3265,12 @@ _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" }

Is the error coming somewhere from the new build_invoke function?  That'd
be surprising since we pass tf_none to it, which should suppress such
errors.  (You can probably break on cxx_incomplete_type_diagnostic to
find out where it's coming from.)

>  
>  #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
> 
>
Ken Matsui March 8, 2024, 5:35 p.m. UTC | #2
On Fri, Mar 8, 2024 at 9:22 AM Patrick Palka <ppalka@redhat.com> wrote:
>
> On Wed, 28 Feb 2024, 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.
> >
> > 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 9af233bcc75..093d85a51a8 100644
> > --- a/libstdc++-v3/include/std/type_traits
> > +++ b/libstdc++-v3/include/std/type_traits
> > @@ -3265,8 +3265,12 @@ _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" }
>
> Is the error coming somewhere from the new build_invoke function?  That'd
> be surprising since we pass tf_none to it, which should suppress such
> errors.  (You can probably break on cxx_incomplete_type_diagnostic to
> find out where it's coming from.)

Hi Patrick,

Thank you for your review!

This error comes from cxx_incomplete_type_diagnostic in
check_trait_type, i.e., before the new build_invoke function.  As we
discussed previously, it would be better if we could produce
diagnostics that are in harmony with libstdc++.

>
> >
> >  #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
> >
> >
>
diff mbox series

Patch

diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
index 9af233bcc75..093d85a51a8 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -3265,8 +3265,12 @@  _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>