Make integer sequence et al. available in C++11 (#1859)

* Make integer_sequence et al. available in C++11

So Thrust can depend on it.

Co-authored-by: Michael Schellenberger Costa <[email protected]>

Author: bernhardmgruber

docs/thrust/api_docs/utility/type_traits.rst

@@ -7,7 +7,6 @@ Type Traits
    :glob:
    :maxdepth: 1
 
-   ${repo_docs_api_path}/*struct*integer__sequence*
    ${repo_docs_api_path}/*struct*proclaim__contiguous__iterator*
    ${repo_docs_api_path}/*struct*conjunction*
    ${repo_docs_api_path}/*struct*disjunction*

libcudacxx/include/cuda/std/__utility/integer_sequence.h

@@ -39,7 +39,7 @@ struct __integer_sequence
   using __to_tuple_indices = __tuple_indices<(_Values + _Sp)...>;
 };
 
-#if !__has_builtin(__make_integer_seq) || defined(_LIBCUDACXX_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE)
+#ifndef _LIBCUDACXX_HAS_MAKE_INTEGER_SEQ
 
 namespace __detail
 {
@@ -170,9 +170,9 @@ struct __parity<7>
 
 } // namespace __detail
 
-#endif // !__has_builtin(__make_integer_seq) || defined(_LIBCUDACXX_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE)
+#endif // !_LIBCUDACXX_HAS_MAKE_INTEGER_SEQ
 
-#if __has_builtin(__make_integer_seq)
+#ifdef _LIBCUDACXX_HAS_MAKE_INTEGER_SEQ
 template <size_t _Ep, size_t _Sp>
 using __make_indices_imp =
   typename __make_integer_seq<__integer_sequence, size_t, _Ep - _Sp>::template __to_tuple_indices<_Sp>;
@@ -182,8 +182,6 @@ using __make_indices_imp = typename __detail::__make<_Ep - _Sp>::type::template
 
 #endif
 
-#if _CCCL_STD_VER > 2011
-
 template <class _Tp, _Tp... _Ip>
 struct _LIBCUDACXX_TEMPLATE_VIS integer_sequence
 {
@@ -198,12 +196,12 @@ struct _LIBCUDACXX_TEMPLATE_VIS integer_sequence
 template <size_t... _Ip>
 using index_sequence = integer_sequence<size_t, _Ip...>;
 
-#  if __has_builtin(__make_integer_seq) && !defined(_LIBCUDACXX_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE)
+#ifdef _LIBCUDACXX_HAS_MAKE_INTEGER_SEQ
 
 template <class _Tp, _Tp _Ep>
 using __make_integer_sequence _LIBCUDACXX_NODEBUG_TYPE = __make_integer_seq<integer_sequence, _Tp, _Ep>;
 
-#  else
+#else // _LIBCUDACXX_HAS_MAKE_INTEGER_SEQ
 
 template <typename _Tp, _Tp _Np>
 using __make_integer_sequence_unchecked _LIBCUDACXX_NODEBUG_TYPE =
@@ -222,7 +220,7 @@ struct __make_integer_sequence_checked
 template <class _Tp, _Tp _Ep>
 using __make_integer_sequence _LIBCUDACXX_NODEBUG_TYPE = typename __make_integer_sequence_checked<_Tp, _Ep>::type;
 
-#  endif
+#endif // _LIBCUDACXX_HAS_MAKE_INTEGER_SEQ
 
 template <class _Tp, _Tp _Np>
 using make_integer_sequence = __make_integer_sequence<_Tp, _Np>;
@@ -233,8 +231,6 @@ using make_index_sequence = make_integer_sequence<size_t, _Np>;
 template <class... _Tp>
 using index_sequence_for = make_index_sequence<sizeof...(_Tp)>;
 
-#endif // _CCCL_STD_VER > 2011
-
 _LIBCUDACXX_END_NAMESPACE_STD
 
 #endif // _LIBCUDACXX___UTILITY_INTEGER_SEQUENCE_H

libcudacxx/include/cuda/std/detail/libcxx/include/__config

@@ -1284,6 +1284,10 @@ typedef unsigned int char32_t;
 #    define _LIBCUDACXX_HAS_NO_BUILTIN_OPERATOR_NEW_DELETE
 #  endif
 
+#  if __check_builtin(make_integer_seq) && !defined(_LIBCUDACXX_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE)
+#    define _LIBCUDACXX_HAS_MAKE_INTEGER_SEQ
+#  endif
+
 #  define _LIBCUDACXX_DECLARE_STRONG_ENUM(x) enum class _LIBCUDACXX_ENUM_VIS x
 #  define _LIBCUDACXX_DECLARE_STRONG_ENUM_EPILOG(x)
 

libcudacxx/test/libcudacxx/std/utilities/intseq/intseq.general/integer_seq.pass.cpp

@@ -7,7 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// UNSUPPORTED: c++03, c++11
 // <utility>
 
 // class make_integer_sequence

libcudacxx/test/libcudacxx/std/utilities/intseq/intseq.intseq/integer_seq.compile.fail.cpp

@@ -7,8 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// UNSUPPORTED: c++03, c++11
-
 // <utility>
 
 // template<class T, T... I>

libcudacxx/test/libcudacxx/std/utilities/intseq/intseq.intseq/integer_seq.pass.cpp

@@ -7,7 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// UNSUPPORTED: c++03, c++11
 // <utility>
 
 // template<class T, T... I>

libcudacxx/test/libcudacxx/std/utilities/intseq/intseq.make/make_integer_seq.fail.cpp

@@ -12,8 +12,6 @@
 // template<class T, T N>
 //   using make_integer_sequence = integer_sequence<T, 0, 1, ..., N-1>;
 
-// UNSUPPORTED: c++03, c++11
-
 // This test hangs during recursive template instantiation with libstdc++
 // UNSUPPORTED: stdlib=libstdc++
 

libcudacxx/test/libcudacxx/std/utilities/intseq/intseq.make/make_integer_seq.pass.cpp

@@ -12,8 +12,6 @@
 // template<class T, T N>
 //   using make_integer_sequence = integer_sequence<T, 0, 1, ..., N-1>;
 
-// UNSUPPORTED: c++03, c++11
-
 #include <cuda/std/cassert>
 #include <cuda/std/type_traits>
 #include <cuda/std/utility>

libcudacxx/test/libcudacxx/std/utilities/intseq/intseq.make/make_integer_seq_fallback.compile.fail.cpp

@@ -12,8 +12,6 @@
 // template<class T, T N>
 //   using make_integer_sequence = integer_sequence<T, 0, 1, ..., N-1>;
 
-// UNSUPPORTED: c++03, c++11
-
 // This test hangs during recursive template instantiation with libstdc++
 // UNSUPPORTED: stdlib=libstdc++
 

libcudacxx/test/libcudacxx/std/utilities/intseq/intseq.make/make_integer_seq_fallback.pass.cpp

@@ -12,8 +12,6 @@
 // template<class T, T N>
 //   using make_integer_sequence = integer_sequence<T, 0, 1, ..., N-1>;
 
-// UNSUPPORTED: c++03, c++11
-
 #define _LIBCUDACXX_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE
 #include "make_integer_seq.pass.cpp"
 #include "test_macros.h"

thrust/thrust/type_traits/integer_sequence.h

@@ -1,5 +1,5 @@
 /*
- *  Copyright 2008-2021 NVIDIA Corporation
+ *  Copyright 2008-2024 NVIDIA Corporation
  *
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -57,23 +57,8 @@ THRUST_NAMESPACE_BEGIN
  * integer_sequence_push_back \see <a
  * href="https://en.cppreference.com/w/cpp/utility/integer_sequence"><tt>std::integer_sequence</tt></a>
  */
-#if _CCCL_STD_VER >= 2014
 template <typename T, T... Is>
 using integer_sequence = ::cuda::std::integer_sequence<T, Is...>;
-#else
-template <typename T, T... Is>
-struct integer_sequence
-{
-  using type       = integer_sequence;
-  using value_type = T;
-  using size_type  = ::cuda::std::size_t;
-
-  _CCCL_HOST_DEVICE static constexpr size_type size() noexcept
-  {
-    return sizeof...(Is);
-  }
-};
-#endif
 
 ///////////////////////////////////////////////////////////////////////////////
 
@@ -90,46 +75,8 @@ struct integer_sequence
  *  \see integer_sequence_push_back
  *  \see <a href="https://en.cppreference.com/w/cpp/utility/integer_sequence"><tt>std::index_sequence</tt></a>
  */
-#if _CCCL_STD_VER >= 2014
 template <::cuda::std::size_t... Is>
 using index_sequence = ::cuda::std::index_sequence<Is...>;
-#else
-template <::cuda::std::size_t... Is>
-using index_sequence = integer_sequence<::cuda::std::size_t, Is...>;
-#endif
-
-#if _CCCL_STD_VER < 2014
-/*! \cond
- */
-
-namespace detail
-{
-
-/*! \brief Create a new \c integer_sequence containing the elements of \c
- * Sequence0 followed by the elements of \c Sequence1. \c Sequence0::size() is
- * added to each element from \c Sequence1 in the new sequence.
- *
- *  \see integer_sequence
- *  \see index_sequence
- *  \see make_reversed_integer_sequence
- *  \see make_index_sequence
- *  \see make_reversed_index_sequence
- *  \see merge_and_renumber_reversed_integer_sequences_impl
- */
-template <typename Sequence0, typename Sequence1>
-struct merge_and_renumber_integer_sequences_impl;
-template <typename Sequence0, typename Sequence1>
-using merge_and_renumber_integer_sequences =
-  typename merge_and_renumber_integer_sequences_impl<Sequence0, Sequence1>::type;
-
-template <typename T, ::cuda::std::size_t N>
-struct make_integer_sequence_impl;
-
-} // namespace detail
-
-/*! \endcond
- */
-#endif
 
 /*! \brief Create a new \c integer_sequence with elements
  *  <tt>0, 1, 2, ..., N - 1</tt> of type \c T.
@@ -141,49 +88,8 @@ struct make_integer_sequence_impl;
  *  \see make_reversed_index_sequence
  *  \see <a href="https://en.cppreference.com/w/cpp/utility/integer_sequence"><tt>std::make_integer_sequence</tt></a>
  */
-#if _CCCL_STD_VER >= 2014
 template <typename T, ::cuda::std::size_t N>
 using make_integer_sequence = ::cuda::std::make_integer_sequence<T, N>;
-#else
-template <typename T, ::cuda::std::size_t N>
-using make_integer_sequence = typename detail::make_integer_sequence_impl<T, N>::type;
-
-/*! \cond
- */
-
-namespace detail
-{
-
-template <typename T, T... Is0, T... Is1>
-struct merge_and_renumber_integer_sequences_impl<integer_sequence<T, Is0...>, integer_sequence<T, Is1...>>
-{
-  using type = integer_sequence<T, Is0..., (sizeof...(Is0) + Is1)...>;
-};
-
-template <typename T, ::cuda::std::size_t N>
-struct make_integer_sequence_impl
-{
-  using type =
-    merge_and_renumber_integer_sequences<make_integer_sequence<T, N / 2>, make_integer_sequence<T, N - N / 2>>;
-};
-
-template <typename T>
-struct make_integer_sequence_impl<T, 0>
-{
-  using type = integer_sequence<T>;
-};
-
-template <typename T>
-struct make_integer_sequence_impl<T, 1>
-{
-  using type = integer_sequence<T, 0>;
-};
-
-} // namespace detail
-
-/*! \endcond
- */
-#endif
 
 ///////////////////////////////////////////////////////////////////////////////
 
@@ -198,13 +104,8 @@ struct make_integer_sequence_impl<T, 1>
  *  \see make_reversed_index_sequence
  *  \see <a href="https://en.cppreference.com/w/cpp/utility/integer_sequence"><tt>std::make_index_sequence</tt></a>
  */
-#if _CCCL_STD_VER >= 2014
 template <::cuda::std::size_t N>
 using make_index_sequence = ::cuda::std::make_index_sequence<N>;
-#else
-template <::cuda::std::size_t N>
-using make_index_sequence = make_integer_sequence<::cuda::std::size_t, N>;
-#endif
 
 ///////////////////////////////////////////////////////////////////////////////