[v4,2/6] libstdc++: use new built-in trait __is_reference for std::is_reference

Message ID 20230611024657.42846-3-kmatsui@cs.washington.edu
State Accepted
Headers
Series c++, libstdc++: get std::is_object to dispatch to new built-in traits |

Checks

Context Check Description
snail/gcc-patch-check success Github commit url

Commit Message

Ken Matsui June 11, 2023, 2:43 a.m. UTC
  This patch gets std::is_reference to dispatch to new built-in trait
__is_reference.

libstdc++-v3/ChangeLog:

	* include/std/type_traits (is_reference): Use __is_reference built-in
	trait.
	(is_reference_v): Likewise.

Signed-off-by: Ken Matsui <kmatsui@cs.washington.edu>
---
 libstdc++-v3/include/std/type_traits | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)
  

Comments

François Dumont June 12, 2023, 6:09 p.m. UTC | #1
Same remark for all your alike patches.

On 11/06/2023 04:43, Ken Matsui via Libstdc++ wrote:
> This patch gets std::is_reference to dispatch to new built-in trait
> __is_reference.
>
> libstdc++-v3/ChangeLog:
>
> 	* include/std/type_traits (is_reference): Use __is_reference built-in
> 	trait.
> 	(is_reference_v): Likewise.
>
> Signed-off-by: Ken Matsui <kmatsui@cs.washington.edu>
> ---
>   libstdc++-v3/include/std/type_traits | 13 ++++++++-----
>   1 file changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
> index 0e7a9c9c7f3..b2eb4bd3e7f 100644
> --- a/libstdc++-v3/include/std/type_traits
> +++ b/libstdc++-v3/include/std/type_traits
> @@ -639,6 +639,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>     // Composite type categories.
>   
>     /// is_reference
> +#if __has_builtin(__is_reference)
Here you are checking __has_builtin(__is_reference)...
> +  template<typename _Tp>
> +    struct is_reference
> +    : public __bool_constant<__is_reference(_Tp)>
> +    { };
> +#else
>     template<typename _Tp>
>       struct is_reference
>       : public false_type
> @@ -653,6 +659,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>       struct is_reference<_Tp&&>
>       : public true_type
>       { };
> +#endif
>   
>     /// is_arithmetic
>     template<typename _Tp>
> @@ -3193,11 +3200,7 @@ template <typename _Tp>
>   template <typename _Tp>
>     inline constexpr bool is_function_v = is_function<_Tp>::value;
>   template <typename _Tp>
> -  inline constexpr bool is_reference_v = false;
> -template <typename _Tp>
> -  inline constexpr bool is_reference_v<_Tp&> = true;
> -template <typename _Tp>
> -  inline constexpr bool is_reference_v<_Tp&&> = true;
> +  inline constexpr bool is_reference_v = __is_reference(_Tp);
...but not here, why ?
  
Ken Matsui June 12, 2023, 6:13 p.m. UTC | #2
Yes, I have fixed them on my side and am waiting for the test results!
Thank you!

On Mon, Jun 12, 2023 at 11:09 AM François Dumont <frs.dumont@gmail.com>
wrote:

> Same remark for all your alike patches.
>
> On 11/06/2023 04:43, Ken Matsui via Libstdc++ wrote:
> > This patch gets std::is_reference to dispatch to new built-in trait
> > __is_reference.
> >
> > libstdc++-v3/ChangeLog:
> >
> >       * include/std/type_traits (is_reference): Use __is_reference
> built-in
> >       trait.
> >       (is_reference_v): Likewise.
> >
> > Signed-off-by: Ken Matsui <kmatsui@cs.washington.edu>
> > ---
> >   libstdc++-v3/include/std/type_traits | 13 ++++++++-----
> >   1 file changed, 8 insertions(+), 5 deletions(-)
> >
> > diff --git a/libstdc++-v3/include/std/type_traits
> b/libstdc++-v3/include/std/type_traits
> > index 0e7a9c9c7f3..b2eb4bd3e7f 100644
> > --- a/libstdc++-v3/include/std/type_traits
> > +++ b/libstdc++-v3/include/std/type_traits
> > @@ -639,6 +639,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> >     // Composite type categories.
> >
> >     /// is_reference
> > +#if __has_builtin(__is_reference)
> Here you are checking __has_builtin(__is_reference)...
> > +  template<typename _Tp>
> > +    struct is_reference
> > +    : public __bool_constant<__is_reference(_Tp)>
> > +    { };
> > +#else
> >     template<typename _Tp>
> >       struct is_reference
> >       : public false_type
> > @@ -653,6 +659,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> >       struct is_reference<_Tp&&>
> >       : public true_type
> >       { };
> > +#endif
> >
> >     /// is_arithmetic
> >     template<typename _Tp>
> > @@ -3193,11 +3200,7 @@ template <typename _Tp>
> >   template <typename _Tp>
> >     inline constexpr bool is_function_v = is_function<_Tp>::value;
> >   template <typename _Tp>
> > -  inline constexpr bool is_reference_v = false;
> > -template <typename _Tp>
> > -  inline constexpr bool is_reference_v<_Tp&> = true;
> > -template <typename _Tp>
> > -  inline constexpr bool is_reference_v<_Tp&&> = true;
> > +  inline constexpr bool is_reference_v = __is_reference(_Tp);
> ...but not here, why ?
>
> --
Sincerely,
Ken Matsui
  

Patch

diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
index 0e7a9c9c7f3..b2eb4bd3e7f 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -639,6 +639,12 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
   // Composite type categories.
 
   /// is_reference
+#if __has_builtin(__is_reference)
+  template<typename _Tp>
+    struct is_reference
+    : public __bool_constant<__is_reference(_Tp)>
+    { };
+#else
   template<typename _Tp>
     struct is_reference
     : public false_type
@@ -653,6 +659,7 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
     struct is_reference<_Tp&&>
     : public true_type
     { };
+#endif
 
   /// is_arithmetic
   template<typename _Tp>
@@ -3193,11 +3200,7 @@  template <typename _Tp>
 template <typename _Tp>
   inline constexpr bool is_function_v = is_function<_Tp>::value;
 template <typename _Tp>
-  inline constexpr bool is_reference_v = false;
-template <typename _Tp>
-  inline constexpr bool is_reference_v<_Tp&> = true;
-template <typename _Tp>
-  inline constexpr bool is_reference_v<_Tp&&> = true;
+  inline constexpr bool is_reference_v = __is_reference(_Tp);
 template <typename _Tp>
   inline constexpr bool is_arithmetic_v = is_arithmetic<_Tp>::value;
 template <typename _Tp>