Vc/traits/has_contiguous_storage.h

0001 /*  This file is part of the Vc library. {{{
0002 Copyright © 2014-2016 Matthias Kretz <kretz@kde.org>
0003
0004 Redistribution and use in source and binary forms, with or without
0005 modification, are permitted provided that the following conditions are met:
0006     * Redistributions of source code must retain the above copyright
0007       notice, this list of conditions and the following disclaimer.
0008     * Redistributions in binary form must reproduce the above copyright
0009       notice, this list of conditions and the following disclaimer in the
0010       documentation and/or other materials provided with the distribution.
0011     * Neither the names of contributing organizations nor the
0012       names of its contributors may be used to endorse or promote products
0013       derived from this software without specific prior written permission.
0014
0015 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
0016 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
0017 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
0018 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
0019 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
0020 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
0021 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
0022 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
0023 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
0024 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
0025
0026 }}}*/
0027
0028 #ifndef VC_TRAITS_HAS_CONTIGUOUS_STORAGE_H_
0029 #define VC_TRAITS_HAS_CONTIGUOUS_STORAGE_H_
0030
0031 #include <initializer_list>
0032 #include <memory>
0033
0034 #ifdef _LIBCPP_BEGIN_NAMESPACE_STD
0035 _LIBCPP_BEGIN_NAMESPACE_STD
0036 #else
0037 namespace std
0038 {
0039 #endif
0040 #ifdef _WIN32
0041 template <typename T, size_t N> class array;
0042 #else
0043 template <typename T, size_t N> struct array;
0044 #endif
0045 template <typename T, typename Allocator> class vector;
0046 #ifdef _LIBCPP_END_NAMESPACE_STD
0047 _LIBCPP_END_NAMESPACE_STD
0048 #else
0049 }  // namespace std
0050 #endif
0051
0052 namespace Vc_VERSIONED_NAMESPACE
0053 {
0054 namespace Traits
0055 {
0056 namespace has_contiguous_storage_detail
0057 {
0058 // heuristic: consider RandomAccessIterator as abstracting contiguous storage
0059 // case 1: T is a container
0060 template <typename T, typename It = typename T::iterator>
0061 std::is_base_of<std::random_access_iterator_tag,
0062                 typename std::iterator_traits<It>::iterator_category>
0063 test(int);
0064
0065 // case 2: T is an iterator type
0066 template <typename T>
0067 std::is_base_of<std::random_access_iterator_tag,
0068                 typename std::iterator_traits<T>::iterator_category>
0069 test(long);
0070
0071 // case 3: everything else
0072 template <typename T> std::false_type test(...);
0073 }  // namespace has_contiguous_storage_detail
0074
0075 template <typename T>
0076 struct has_contiguous_storage_impl
0077     : public decltype(has_contiguous_storage_detail::test<T>(int())) {
0078 };
0079
0080 template <typename T>
0081 struct has_contiguous_storage
0082     : public has_contiguous_storage_impl<
0083           typename std::remove_cv<typename std::remove_reference<T>::type>::type>
0084 {
0085 };
0086
0087 // spezializations:
0088 template <typename T> struct has_contiguous_storage_impl<const T *> : public std::true_type {};
0089 template <typename T> struct has_contiguous_storage_impl<T *> : public std::true_type {};
0090 template <typename T> struct has_contiguous_storage_impl<std::unique_ptr<T[]>> : public std::true_type {};
0091 template <typename T> struct has_contiguous_storage_impl<std::initializer_list<T>> : public std::true_type {};
0092 template <typename T, std::size_t N> struct has_contiguous_storage_impl<T[N]> : public std::true_type {};
0093 template <typename T, std::size_t N> struct has_contiguous_storage_impl<std::array<T, N>> : public std::true_type {};
0094 template <typename T, typename A> struct has_contiguous_storage_impl<std::vector<T, A>> : public std::true_type {};
0095
0096 }  // namespace Traits
0097 }  // namespace Vc
0098
0099 #endif // VC_TRAITS_HAS_CONTIGUOUS_STORAGE_H_