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From: "François Dumont" <frs.dumont@gmail.com>
To: Ken Matsui <kmatsui@gcc.gnu.org>, gcc-patches <gcc-patches@gcc.gnu.org>
Cc: libstdc++ <libstdc++@gcc.gnu.org>
Subject: Re: [PATCH 1/2] c++, libstdc++: implement __is_pointer built-in trait
Date: Wed, 12 Jul 2023 06:40:48 +0200	[thread overview]
Message-ID: <e2208344-f600-abc0-8830-d810403a164d@gmail.com> (raw)
In-Reply-To: <20230710052310.48116-1-kmatsui@gcc.gnu.org>


On 10/07/2023 07:23, Ken Matsui via Libstdc++ wrote:
> This patch implements built-in trait for std::is_pointer.
>
> gcc/cp/ChangeLog:
>
> 	* cp-trait.def: Define __is_pointer.
> 	* constraint.cc (diagnose_trait_expr): Handle CPTK_IS_POINTER.
> 	* semantics.cc (trait_expr_value): Likewise.
> 	(finish_trait_expr): Likewise.
>
> gcc/testsuite/ChangeLog:
>
> 	* g++.dg/ext/has-builtin-1.C: Test existence of __is_pointer.
> 	* g++.dg/ext/is_pointer.C: New test.
> 	* g++.dg/tm/pr46567.C (__is_pointer): Rename to ...
> 	(____is_pointer): ... this.
> 	* g++.dg/torture/20070621-1.C: Likewise.
> 	* g++.dg/torture/pr57107.C: Likewise.
>
> libstdc++-v3/ChangeLog:
>
> 	* include/bits/cpp_type_traits.h (__is_pointer): Rename to ...
> 	(____is_pointer): ... this.
> 	* include/bits/deque.tcc: Use ____is_pointer instead.
> 	* include/bits/stl_algobase.h: Likewise.
>
> Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org>
> ---
>   gcc/cp/constraint.cc                        |  3 ++
>   gcc/cp/cp-trait.def                         |  1 +
>   gcc/cp/semantics.cc                         |  4 ++
>   gcc/testsuite/g++.dg/ext/has-builtin-1.C    |  3 ++
>   gcc/testsuite/g++.dg/ext/is_pointer.C       | 51 +++++++++++++++++++++
>   gcc/testsuite/g++.dg/tm/pr46567.C           | 22 ++++-----
>   gcc/testsuite/g++.dg/torture/20070621-1.C   |  4 +-
>   gcc/testsuite/g++.dg/torture/pr57107.C      |  4 +-
>   libstdc++-v3/include/bits/cpp_type_traits.h |  6 +--
>   libstdc++-v3/include/bits/deque.tcc         |  6 +--
>   libstdc++-v3/include/bits/stl_algobase.h    |  6 +--
>   11 files changed, 86 insertions(+), 24 deletions(-)
>   create mode 100644 gcc/testsuite/g++.dg/ext/is_pointer.C
>
> diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
> index 8cf0f2d0974..30266204eb5 100644
> --- a/gcc/cp/constraint.cc
> +++ b/gcc/cp/constraint.cc
> @@ -3751,6 +3751,9 @@ diagnose_trait_expr (tree expr, tree args)
>       case CPTK_IS_UNION:
>         inform (loc, "  %qT is not a union", t1);
>         break;
> +    case CPTK_IS_POINTER:
> +      inform (loc, "  %qT is not a pointer", t1);
> +      break;
>       case CPTK_IS_AGGREGATE:
>         inform (loc, "  %qT is not an aggregate", t1);
>         break;
> diff --git a/gcc/cp/cp-trait.def b/gcc/cp/cp-trait.def
> index 8b7fece0cc8..b7c263e9a77 100644
> --- a/gcc/cp/cp-trait.def
> +++ b/gcc/cp/cp-trait.def
> @@ -82,6 +82,7 @@ DEFTRAIT_EXPR (IS_TRIVIALLY_ASSIGNABLE, "__is_trivially_assignable", 2)
>   DEFTRAIT_EXPR (IS_TRIVIALLY_CONSTRUCTIBLE, "__is_trivially_constructible", -1)
>   DEFTRAIT_EXPR (IS_TRIVIALLY_COPYABLE, "__is_trivially_copyable", 1)
>   DEFTRAIT_EXPR (IS_UNION, "__is_union", 1)
> +DEFTRAIT_EXPR (IS_POINTER, "__is_pointer", 1)
>   DEFTRAIT_EXPR (REF_CONSTRUCTS_FROM_TEMPORARY, "__reference_constructs_from_temporary", 2)
>   DEFTRAIT_EXPR (REF_CONVERTS_FROM_TEMPORARY, "__reference_converts_from_temporary", 2)
>   /* FIXME Added space to avoid direct usage in GCC 13.  */
> diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
> index 8fb47fd179e..68f8a4fe85b 100644
> --- a/gcc/cp/semantics.cc
> +++ b/gcc/cp/semantics.cc
> @@ -12118,6 +12118,9 @@ trait_expr_value (cp_trait_kind kind, tree type1, tree type2)
>       case CPTK_IS_UNION:
>         return type_code1 == UNION_TYPE;
>   
> +    case CPTK_IS_POINTER:
> +      return TYPE_PTR_P (type1);
> +
>       case CPTK_IS_ASSIGNABLE:
>         return is_xible (MODIFY_EXPR, type1, type2);
>   
> @@ -12296,6 +12299,7 @@ finish_trait_expr (location_t loc, cp_trait_kind kind, tree type1, tree type2)
>       case CPTK_IS_ENUM:
>       case CPTK_IS_UNION:
>       case CPTK_IS_SAME:
> +    case CPTK_IS_POINTER:
>         break;
>   
>       case CPTK_IS_LAYOUT_COMPATIBLE:
> diff --git a/gcc/testsuite/g++.dg/ext/has-builtin-1.C b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> index f343e153e56..9dace5cbd48 100644
> --- a/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> +++ b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> @@ -146,3 +146,6 @@
>   #if !__has_builtin (__remove_cvref)
>   # error "__has_builtin (__remove_cvref) failed"
>   #endif
> +#if !__has_builtin (__is_pointer)
> +# error "__has_builtin (__is_pointer) failed"
> +#endif
> diff --git a/gcc/testsuite/g++.dg/ext/is_pointer.C b/gcc/testsuite/g++.dg/ext/is_pointer.C
> new file mode 100644
> index 00000000000..d6e39565950
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/ext/is_pointer.C
> @@ -0,0 +1,51 @@
> +// { dg-do compile { target c++11 } }
> +
> +#define SA(X) static_assert((X),#X)
> +
> +SA(!__is_pointer(int));
> +SA(__is_pointer(int*));
> +SA(__is_pointer(int**));
> +
> +SA(__is_pointer(const int*));
> +SA(__is_pointer(const int**));
> +SA(__is_pointer(int* const));
> +SA(__is_pointer(int** const));
> +SA(__is_pointer(int* const* const));
> +
> +SA(__is_pointer(volatile int*));
> +SA(__is_pointer(volatile int**));
> +SA(__is_pointer(int* volatile));
> +SA(__is_pointer(int** volatile));
> +SA(__is_pointer(int* volatile* volatile));
> +
> +SA(__is_pointer(const volatile int*));
> +SA(__is_pointer(const volatile int**));
> +SA(__is_pointer(const int* volatile));
> +SA(__is_pointer(volatile int* const));
> +SA(__is_pointer(int* const volatile));
> +SA(__is_pointer(const int** volatile));
> +SA(__is_pointer(volatile int** const));
> +SA(__is_pointer(int** const volatile));
> +SA(__is_pointer(int* const* const volatile));
> +SA(__is_pointer(int* volatile* const volatile));
> +SA(__is_pointer(int* const volatile* const volatile));
> +
> +SA(!__is_pointer(int&));
> +SA(!__is_pointer(const int&));
> +SA(!__is_pointer(volatile int&));
> +SA(!__is_pointer(const volatile int&));
> +
> +SA(!__is_pointer(int&&));
> +SA(!__is_pointer(const int&&));
> +SA(!__is_pointer(volatile int&&));
> +SA(!__is_pointer(const volatile int&&));
> +
> +SA(!__is_pointer(int[3]));
> +SA(!__is_pointer(const int[3]));
> +SA(!__is_pointer(volatile int[3]));
> +SA(!__is_pointer(const volatile int[3]));
> +
> +SA(!__is_pointer(int(int)));
> +SA(__is_pointer(int(*const)(int)));
> +SA(__is_pointer(int(*volatile)(int)));
> +SA(__is_pointer(int(*const volatile)(int)));
> diff --git a/gcc/testsuite/g++.dg/tm/pr46567.C b/gcc/testsuite/g++.dg/tm/pr46567.C
> index 6d791484448..0896035390e 100644
> --- a/gcc/testsuite/g++.dg/tm/pr46567.C
> +++ b/gcc/testsuite/g++.dg/tm/pr46567.C
> @@ -192,13 +192,13 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
>         typedef __true_type __type;
>       };
>     template<typename _Tp>
> -    struct __is_pointer
> +    struct ____is_pointer
>       {
>         enum { __value = 0 };
>         typedef __false_type __type;
>       };
>     template<typename _Tp>
> -    struct __is_pointer<_Tp*>
> +    struct ____is_pointer<_Tp*>
>       {
>         enum { __value = 1 };
>         typedef __true_type __type;
> @@ -226,7 +226,7 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
>       { };
>     template<typename _Tp>
>       struct __is_scalar
> -    : public __traitor<__is_arithmetic<_Tp>, __is_pointer<_Tp> >
> +    : public __traitor<__is_arithmetic<_Tp>, ____is_pointer<_Tp> >
>       { };
>     template<typename _Tp>
>       struct __is_char
> @@ -1202,8 +1202,8 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
>         typedef typename iterator_traits<_OI>::value_type _ValueTypeO;
>         typedef typename iterator_traits<_II>::iterator_category _Category;
>         const bool __simple = (__is_pod(_ValueTypeI)
> -		      && __is_pointer<_II>::__value
> -		      && __is_pointer<_OI>::__value
> +		      && ____is_pointer<_II>::__value
> +		      && ____is_pointer<_OI>::__value
>   	&& __are_same<_ValueTypeI, _ValueTypeO>::__value);
>         return std::__copy_move<_IsMove, __simple,
>   		       _Category>::__copy_m(__first, __last, __result);
> @@ -1294,8 +1294,8 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
>         typedef typename iterator_traits<_BI2>::value_type _ValueType2;
>         typedef typename iterator_traits<_BI1>::iterator_category _Category;
>         const bool __simple = (__is_pod(_ValueType1)
> -		      && __is_pointer<_BI1>::__value
> -		      && __is_pointer<_BI2>::__value
> +		      && ____is_pointer<_BI1>::__value
> +		      && ____is_pointer<_BI2>::__value
>   	&& __are_same<_ValueType1, _ValueType2>::__value);
>         return std::__copy_move_backward<_IsMove, __simple,
>   				_Category>::__copy_move_b(__first,
> @@ -1426,8 +1426,8 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
>         typedef typename iterator_traits<_II1>::value_type _ValueType1;
>         typedef typename iterator_traits<_II2>::value_type _ValueType2;
>         const bool __simple = (__is_integer<_ValueType1>::__value
> -		      && __is_pointer<_II1>::__value
> -		      && __is_pointer<_II2>::__value
> +		      && ____is_pointer<_II1>::__value
> +		      && ____is_pointer<_II2>::__value
>   	&& __are_same<_ValueType1, _ValueType2>::__value);
>         return std::__equal<__simple>::equal(__first1, __last1, __first2);
>       }
> @@ -1515,8 +1515,8 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
>    (__is_byte<_ValueType1>::__value && __is_byte<_ValueType2>::__value
>     && !__gnu_cxx::__numeric_traits<_ValueType1>::__is_signed
>     && !__gnu_cxx::__numeric_traits<_ValueType2>::__is_signed
> -  && __is_pointer<_II1>::__value
> -  && __is_pointer<_II2>::__value);
> +  && ____is_pointer<_II1>::__value
> +  && ____is_pointer<_II2>::__value);
>         return std::__lexicographical_compare<__simple>::__lc(__first1, __last1,
>   	   __first2, __last2);
>       }
> diff --git a/gcc/testsuite/g++.dg/torture/20070621-1.C b/gcc/testsuite/g++.dg/torture/20070621-1.C
> index d8a6a76b6b0..9ae96717e4f 100644
> --- a/gcc/testsuite/g++.dg/torture/20070621-1.C
> +++ b/gcc/testsuite/g++.dg/torture/20070621-1.C
> @@ -18,7 +18,7 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
>           enum {
>     __value = 0 };
>         };
> -    template<typename _Tp>     struct __is_pointer     {
> +    template<typename _Tp>     struct ____is_pointer     {
>           enum {
>     __value = 0 };
>         };
> @@ -49,7 +49,7 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
>       template<typename _II1, typename _II2>     inline bool     __equal_aux(_II1 __first1, _II1 __last1, _II2 __first2)     {
>           typedef typename iterator_traits<_II1>::value_type _ValueType1;
>           typedef typename iterator_traits<_II2>::value_type _ValueType2;
> -        const bool __simple = (__is_integer<_ValueType1>::__value                       && __is_pointer<_II1>::__value                       && __is_pointer<_II2>::__value         && __are_same<_ValueType1, _ValueType2>::__value);
> +        const bool __simple = (__is_integer<_ValueType1>::__value                       && ____is_pointer<_II1>::__value                       && ____is_pointer<_II2>::__value         && __are_same<_ValueType1, _ValueType2>::__value);
>           return std::__equal<__simple>::equal(__first1, __last1, __first2);
>         }
>       template<typename _II1, typename _II2>     inline bool     equal(_II1 __first1, _II1 __last1, _II2 __first2)     {
> diff --git a/gcc/testsuite/g++.dg/torture/pr57107.C b/gcc/testsuite/g++.dg/torture/pr57107.C
> index 4dbd32bd298..1fcf337ee58 100644
> --- a/gcc/testsuite/g++.dg/torture/pr57107.C
> +++ b/gcc/testsuite/g++.dg/torture/pr57107.C
> @@ -17,7 +17,7 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
>   	enum {
>   	    __value = 0 };
>       };
> -    template<typename _Tp>     struct __is_pointer     {
> +    template<typename _Tp>     struct ____is_pointer     {
>   	enum {
>   	    __value = 0 };
>       };
> @@ -27,7 +27,7 @@ namespace std __attribute__ ((__visibility__ ("default"))) {
>       };
>       template<typename _Tp>     struct __is_arithmetic     : public __traitor<__is_integer<_Tp>, __is_floating<_Tp> >     {
>       };
> -    template<typename _Tp>     struct __is_scalar     : public __traitor<__is_arithmetic<_Tp>, __is_pointer<_Tp> >     {
> +    template<typename _Tp>     struct __is_scalar     : public __traitor<__is_arithmetic<_Tp>, ____is_pointer<_Tp> >     {
>       };
>   }
>   namespace __gnu_cxx __attribute__ ((__visibility__ ("default"))) {
> diff --git a/libstdc++-v3/include/bits/cpp_type_traits.h b/libstdc++-v3/include/bits/cpp_type_traits.h
> index 4312f32a4e0..3999898ffa6 100644
> --- a/libstdc++-v3/include/bits/cpp_type_traits.h
> +++ b/libstdc++-v3/include/bits/cpp_type_traits.h
> @@ -364,14 +364,14 @@ __INT_N(__GLIBCXX_TYPE_INT_N_3)
>     // Pointer types
>     //
>     template<typename _Tp>
> -    struct __is_pointer
> +    struct ____is_pointer

It makes the creation of builtin __is_pointer pointless for libstdc++ if 
you do it this way, no ?

IMHO you should do something like:

   //
   // Pointer types
   //
   template<typename _Tp>
     struct ____is_pointer
     {
#if __has_builtin(__is_pointer)
       enum { __value = __is_pointer(_Tp) };
       typedef typename __truth_type<__value>::__type __type;
#else
       enum { __value = 0 };
       typedef __false_type __type;
#endif
     };

#if !__has_builtin(__is_pointer)
   template<typename _Tp>
     struct __is_pointer<_Tp*>
     {
       enum { __value = 1 };
       typedef __true_type __type;
     };
#endif


>       {
>         enum { __value = 0 };
>         typedef __false_type __type;
>       };
>   
>     template<typename _Tp>
> -    struct __is_pointer<_Tp*>
> +    struct ____is_pointer<_Tp*>
>       {
>         enum { __value = 1 };
>         typedef __true_type __type;
> @@ -390,7 +390,7 @@ __INT_N(__GLIBCXX_TYPE_INT_N_3)
>     //
>     template<typename _Tp>
>       struct __is_scalar
> -    : public __traitor<__is_arithmetic<_Tp>, __is_pointer<_Tp> >
> +    : public __traitor<__is_arithmetic<_Tp>, ____is_pointer<_Tp> >
>       { };
>   
>     //
> diff --git a/libstdc++-v3/include/bits/deque.tcc b/libstdc++-v3/include/bits/deque.tcc
> index a212b8a6940..9f5593fac51 100644
> --- a/libstdc++-v3/include/bits/deque.tcc
> +++ b/libstdc++-v3/include/bits/deque.tcc
> @@ -1273,7 +1273,7 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
>       {
>         const bool __simple =
>   	(__is_memcmp_ordered_with<_Tp1, _Tp2>::__value
> -	 && __is_pointer<_Ptr>::__value
> +	 && ____is_pointer<_Ptr>::__value
>   #if __cplusplus > 201703L && __cpp_lib_concepts
>   	 // For C++20 iterator_traits<volatile T*>::value_type is non-volatile
>   	 // so __is_byte<T> could be true, but we can't use memcmp with
> @@ -1329,8 +1329,8 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
>       {
>         const bool __simple =
>   	(__is_memcmp_ordered_with<_Tp1, _Tp2>::__value
> -	 && __is_pointer<_Ptr1>::__value
> -	 && __is_pointer<_Ptr2>::__value
> +	 && ____is_pointer<_Ptr1>::__value
> +	 && ____is_pointer<_Ptr2>::__value
>   #if __cplusplus > 201703L && __cpp_lib_concepts
>   	 // For C++20 iterator_traits<volatile T*>::value_type is non-volatile
>   	 // so __is_byte<T> could be true, but we can't use memcmp with
> diff --git a/libstdc++-v3/include/bits/stl_algobase.h b/libstdc++-v3/include/bits/stl_algobase.h
> index dd95e94f7e9..b061c6c1185 100644
> --- a/libstdc++-v3/include/bits/stl_algobase.h
> +++ b/libstdc++-v3/include/bits/stl_algobase.h
> @@ -1214,7 +1214,7 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
>       {
>         typedef typename iterator_traits<_II1>::value_type _ValueType1;
>         const bool __simple = ((__is_integer<_ValueType1>::__value
> -			      || __is_pointer<_ValueType1>::__value)
> +			      || ____is_pointer<_ValueType1>::__value)
>   			     && __memcmpable<_II1, _II2>::__value);
>         return std::__equal<__simple>::equal(__first1, __last1, __first2);
>       }
> @@ -1377,8 +1377,8 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
>         typedef typename iterator_traits<_II2>::value_type _ValueType2;
>         const bool __simple =
>   	(__is_memcmp_ordered_with<_ValueType1, _ValueType2>::__value
> -	 && __is_pointer<_II1>::__value
> -	 && __is_pointer<_II2>::__value
> +	 && ____is_pointer<_II1>::__value
> +	 && ____is_pointer<_II2>::__value
>   #if __cplusplus > 201703L && __cpp_lib_concepts
>   	 // For C++20 iterator_traits<volatile T*>::value_type is non-volatile
>   	 // so __is_byte<T> could be true, but we can't use memcmp with

  parent reply	other threads:[~2023-07-12  4:40 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-07-10  5:23 Ken Matsui
2023-07-10  5:23 ` [PATCH 2/2] libstdc++: use new built-in trait __is_pointer Ken Matsui
2023-07-10  5:32   ` Daniel Krügler
2023-07-10  5:34     ` Ken Matsui
2023-07-10  5:38 ` [PATCH v2 1/2] c++, libstdc++: implement __is_pointer built-in trait Ken Matsui
2023-07-10  5:38   ` [PATCH v2 2/2] libstdc++: use new built-in trait __is_pointer Ken Matsui
2023-07-10  5:50   ` [PATCH v2 1/2] c++, libstdc++: implement __is_pointer built-in trait Ken Matsui
2023-07-12 10:01     ` Jonathan Wakely
2023-07-12 20:42       ` Ken Matsui
2023-07-13  1:11         ` [PATCH v3 1/2] c++, libstdc++: Implement " Ken Matsui
2023-07-13  1:11           ` [PATCH v3 2/2] libstdc++: Use new built-in trait __is_pointer Ken Matsui
2023-07-13  1:13           ` [PATCH v3 1/2] c++, libstdc++: Implement __is_pointer built-in trait Ken Matsui
2023-07-13  1:15             ` Ken Matsui
2023-07-13  3:16           ` [PATCH v4 " Ken Matsui
2023-07-13  3:16             ` [PATCH v4 2/2] libstdc++: Use new built-in trait __is_pointer Ken Matsui
2023-07-13  3:19             ` [PATCH v5 1/2] c++, libstdc++: Implement __is_pointer built-in trait Ken Matsui
2023-07-13  3:19               ` [PATCH v5 2/2] libstdc++: Use new built-in trait __is_pointer Ken Matsui
2023-07-13 20:48                 ` [PATCH v6 1/2] c++, libstdc++: Implement __is_pointer built-in trait Ken Matsui
2023-07-13 20:48                   ` [PATCH v6 2/2] libstdc++: Use new built-in trait __is_pointer Ken Matsui
2023-09-01 13:00                     ` [PING][PATCH " Ken Matsui
2023-07-13  9:21         ` [PATCH v2 1/2] c++, libstdc++: implement __is_pointer built-in trait Jonathan Wakely
2023-07-13 20:04           ` Ken Matsui
2023-07-14 10:48             ` Jonathan Wakely
2023-07-14 10:49               ` Jonathan Wakely
2023-07-14 19:55                 ` Ken Matsui
2023-07-12  4:40 ` François Dumont [this message]
2023-07-12  9:47   ` [PATCH " Jonathan Wakely
2023-07-12  9:48 ` Jonathan Wakely

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