Implement enable_borrowed_range (#1196)

libcudacxx/include/cuda/std/detail/libcxx/include/CMakeLists.txt

@@ -166,6 +166,7 @@ set(files
   __mutex_base
   __node_handle
   __nullptr
+  __ranges/enable_borrowed_range.h
   __split_buffer
   __sso_allocator
   __std_stream

libcudacxx/include/cuda/std/detail/libcxx/include/__ranges/enable_borrowed_range.h

@@ -0,0 +1,43 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+// SPDX-FileCopyrightText: Copyright (c) 2023 NVIDIA CORPORATION & AFFILIATES.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCUDACXX___RANGES_ENABLE_BORROWED_RANGE_H
+#define _LIBCUDACXX___RANGES_ENABLE_BORROWED_RANGE_H
+
+// These customization variables are used in <span> and <string_view>. The
+// separate header is used to avoid including the entire <ranges> header in
+// <span> and <string_view>.
+
+#ifndef __cuda_std__
+#include <__config>
+#endif // __cuda_std__
+
+#if defined(_CCCL_IMPLICIT_SYSTEM_HEADER_GCC)
+#  pragma GCC system_header
+#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_CLANG)
+#  pragma clang system_header
+#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_MSVC)
+#  pragma system_header
+#endif // no system header
+
+#if _LIBCUDACXX_STD_VER > 14
+
+_LIBCUDACXX_BEGIN_NAMESPACE_RANGES
+
+// [range.range], ranges
+
+template <class>
+_LIBCUDACXX_INLINE_VAR constexpr bool enable_borrowed_range = false;
+
+_LIBCUDACXX_END_NAMESPACE_RANGES
+
+#endif // _LIBCUDACXX_STD_VER > 14
+
+#endif // _LIBCUDACXX___RANGES_ENABLE_BORROWED_RANGE_H

libcudacxx/include/cuda/std/detail/libcxx/include/ranges

@@ -0,0 +1,338 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+// SPDX-FileCopyrightText: Copyright (c) 2023 NVIDIA CORPORATION & AFFILIATES.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCUDACXX_RANGES
+#define _LIBCUDACXX_RANGES
+
+/*
+
+#include <compare>              // see [compare.syn]
+#include <initializer_list>     // see [initializer.list.syn]
+#include <iterator>             // see [iterator.synopsis]
+
+namespace std::ranges {
+  inline namespace unspecified {
+    // [range.access], range access
+    inline constexpr unspecified begin = unspecified;
+    inline constexpr unspecified end = unspecified;
+    inline constexpr unspecified cbegin = unspecified;
+    inline constexpr unspecified cend = unspecified;
+
+    inline constexpr unspecified size = unspecified;
+    inline constexpr unspecified ssize = unspecified;
+  }
+
+  // [range.range], ranges
+  template<class T>
+    concept range = see below;
+
+  template<class T>
+    inline constexpr bool enable_borrowed_range = false;
+
+  template<class T>
+    using iterator_t = decltype(ranges::begin(declval<T&>()));
+  template<range R>
+    using sentinel_t = decltype(ranges::end(declval<R&>()));
+  template<range R>
+    using range_difference_t = iter_difference_t<iterator_t<R>>;
+  template<sized_range R>
+    using range_size_t = decltype(ranges::size(declval<R&>()));
+  template<range R>
+    using range_value_t = iter_value_t<iterator_t<R>>;
+  template<range R>
+    using range_reference_t = iter_reference_t<iterator_t<R>>;
+  template<range R>
+    using range_rvalue_reference_t = iter_rvalue_reference_t<iterator_t<R>>;
+
+  // [range.sized], sized ranges
+  template<class>
+    inline constexpr bool disable_sized_range = false;
+
+  template<class T>
+    concept sized_range = ...;
+
+  // [range.view], views
+  template<class T>
+    inline constexpr bool enable_view = ...;
+
+  struct view_base { };
+
+  template<class T>
+    concept view = ...;
+
+  // [range.refinements], other range refinements
+  template<class R, class T>
+    concept output_range = see below;
+
+  template<class T>
+    concept input_range = see below;
+
+  template<class T>
+    concept forward_range = see below;
+
+  template<class T>
+  concept bidirectional_range = see below;
+
+  template<class T>
+  concept random_access_range = see below;
+
+  template<class T>
+  concept contiguous_range = see below;
+
+  template <class _Tp>
+    concept common_range = see below;
+
+  template<class T>
+  concept viewable_range = see below;
+
+  // [view.interface], class template view_interface
+  template<class D>
+    requires is_class_v<D> && same_as<D, remove_cv_t<D>>
+  class view_interface;
+
+  // [range.subrange], sub-ranges
+  enum class subrange_kind : bool { unsized, sized };
+
+  template<input_or_output_iterator I, sentinel_for<I> S = I, subrange_kind K = see below>
+    requires (K == subrange_kind::sized || !sized_sentinel_for<S, I>)
+  class subrange;
+
+  template<class I, class S, subrange_kind K>
+    inline constexpr bool enable_borrowed_range<subrange<I, S, K>> = true;
+
+  // [range.dangling], dangling iterator handling
+  struct dangling;
+
+  template<range R>
+    using borrowed_iterator_t = see below;
+
+  template<range R>
+    using borrowed_subrange_t = see below;
+
+  // [range.empty], empty view
+  template<class T>
+    requires is_object_v<T>
+  class empty_view;
+
+  template<class T>
+    inline constexpr bool enable_borrowed_range<empty_view<T>> = true;
+
+  namespace views {
+    template<class T>
+      inline constexpr empty_view<T> empty{};
+  }
+
+  // [range.all], all view
+  namespace views {
+    inline constexpr unspecified all = unspecified;
+
+    template<viewable_range R>
+      using all_t = decltype(all(declval<R>()));
+  }
+
+  template<range R>
+    requires is_object_v<R>
+  class ref_view;
+
+  template<class T>
+    inline constexpr bool enable_borrowed_range<ref_view<T>> = true;
+
+  template<range R>
+    requires see below
+  class owning_view;
+
+  template<class T>
+    inline constexpr bool enable_borrowed_range<owning_view<T>> = enable_borrowed_range<T>;
+
+  // [range.filter], filter view
+  template<input_range V, indirect_unary_predicate<iterator_t<V>> Pred>
+    requires view<V> && is_object_v<Pred>
+  class filter_view;
+
+  namespace views {
+    inline constexpr unspecified filter = unspecified;
+  }
+
+  // [range.drop], drop view
+  template<view V>
+    class drop_view;
+
+  template<class T>
+    inline constexpr bool enable_borrowed_range<drop_view<T>> = enable_borrowed_range<T>;
+
+  // [range.drop.while], drop while view
+  template<view V, class Pred>
+    requires input_range<V> && is_object_v<Pred> &&
+             indirect_unary_predicate<const Pred, iterator_t<V>>
+    class drop_while_view;
+
+  template<class T, class Pred>
+    inline constexpr bool enable_borrowed_range<drop_while_view<T, Pred>> =
+      enable_borrowed_range<T>;
+
+  namespace views { inline constexpr unspecified drop_while = unspecified; }
+
+  // [range.transform], transform view
+  template<input_range V, copy_constructible F>
+    requires view<V> && is_object_v<F> &&
+             regular_invocable<F&, range_reference_t<V>> &&
+             can-reference<invoke_result_t<F&, range_reference_t<V>>>
+  class transform_view;
+
+  // [range.counted], counted view
+  namespace views { inline constexpr unspecified counted = unspecified; }
+
+  // [range.common], common view
+  template<view V>
+    requires (!common_range<V> && copyable<iterator_t<V>>)
+  class common_view;
+
+ // [range.reverse], reverse view
+  template<view V>
+    requires bidirectional_range<V>
+  class reverse_view;
+
+  template<class T>
+    inline constexpr bool enable_borrowed_range<reverse_view<T>> = enable_borrowed_range<T>;
+
+  template<class T>
+  inline constexpr bool enable_borrowed_range<common_view<T>> = enable_borrowed_range<T>;
+
+   // [range.take], take view
+  template<view> class take_view;
+
+  template<class T>
+  inline constexpr bool enable_borrowed_range<take_view<T>> = enable_borrowed_range<T>;
+
+    // [range.take.while], take while view
+  template<view V, class Pred>
+    requires input_range<V> && is_object_v<Pred> &&
+             indirect_unary_predicate<const Pred, iterator_t<V>>
+    class take_while_view;
+
+  namespace views { inline constexpr unspecified take_while = unspecified; }
+
+  template<copy_constructible T>
+    requires is_object_v<T>
+  class single_view;
+
+  template<weakly_incrementable W, semiregular Bound = unreachable_sentinel_t>
+    requires weakly-equality-comparable-with<W, Bound> && copyable<W>
+  class iota_view;
+
+  template<class W, class Bound>
+    inline constexpr bool enable_borrowed_range<iota_view<W, Bound>> = true;
+
+  // [range.join], join view
+  template<input_range V>
+    requires view<V> && input_range<range_reference_t<V>>
+  class join_view;
+
+  // [range.lazy.split], lazy split view
+  template<class R>
+    concept tiny-range = see below;   // exposition only
+
+  template<input_range V, forward_range Pattern>
+    requires view<V> && view<Pattern> &&
+             indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to> &&
+             (forward_range<V> || tiny-range<Pattern>)
+  class lazy_split_view;
+
+  namespace views {
+    inline constexpr unspecified lazy_split = unspecified;
+  }
+
+  // [range.istream], istream view
+  template<movable Val, class CharT, class Traits = char_traits<CharT>>
+    requires see below
+  class basic_istream_view;
+
+  template<class Val>
+    using istream_view = basic_istream_view<Val, char>;
+
+  template<class Val>
+    using wistream_view = basic_istream_view<Val, wchar_t>;
+
+  namespace views { template<class T> inline constexpr unspecified istream = unspecified; }
+
+  // [range.zip], zip view
+  template<input_range... Views>
+    requires (view<Views> && ...) && (sizeof...(Views) > 0)
+  class zip_view;        // C++2b
+
+  template<class... Views>
+    inline constexpr bool enable_borrowed_range<zip_view<Views...>> =    // C++2b
+      (enable_borrowed_range<Views> && ...);
+
+  namespace views { inline constexpr unspecified zip = unspecified; }    // C++2b
+}
+
+namespace std {
+  namespace views = ranges::views;
+
+  template<class T> struct tuple_size;
+  template<size_t I, class T> struct tuple_element;
+
+  template<class I, class S, ranges::subrange_kind K>
+  struct tuple_size<ranges::subrange<I, S, K>>
+    : integral_constant<size_t, 2> {};
+
+  template<class I, class S, ranges::subrange_kind K>
+  struct tuple_element<0, ranges::subrange<I, S, K>> {
+    using type = I;
+  };
+
+  template<class I, class S, ranges::subrange_kind K>
+  struct tuple_element<1, ranges::subrange<I, S, K>> {
+    using type = S;
+  };
+
+  template<class I, class S, ranges::subrange_kind K>
+  struct tuple_element<0, const ranges::subrange<I, S, K>> {
+    using type = I;
+  };
+
+  template<class I, class S, ranges::subrange_kind K>
+  struct tuple_element<1, const ranges::subrange<I, S, K>> {
+    using type = S;
+  };
+}
+*/
+
+#ifndef __cuda_std__
+#include <__config>
+#endif // __cuda_std__
+
+#include "__assert" // all public C++ headers provide the assertion handler
+#include "__ranges/enable_borrowed_range.h"
+
+// standard-mandated includes
+#include "version"
+
+// [ranges.syn]
+#ifndef _LIBCUDACXX_HAS_NO_SPACESHIP_OPERATOR
+#include "compare"
+#endif // _LIBCUDACXX_HAS_NO_SPACESHIP_OPERATOR
+#include "initializer_list"
+#include "iterator"
+
+// [tuple.helper]
+#include "__tuple_dir/tuple_element.h"
+#include "__tuple_dir/tuple_size.h"
+
+#if defined(_CCCL_IMPLICIT_SYSTEM_HEADER_GCC)
+#  pragma GCC system_header
+#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_CLANG)
+#  pragma clang system_header
+#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_MSVC)
+#  pragma system_header
+#endif // no system header
+
+#endif // _LIBCUDACXX_RANGES