Vc/common/alignedbase.h

0001 /*  This file is part of the Vc library. {{{
0002 Copyright © 2015 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_COMMON_ALIGNEDBASE_H_
0029 #define VC_COMMON_ALIGNEDBASE_H_
0030
0031 #include "types.h"
0032 #include "macros.h"
0033
0034 namespace Vc_VERSIONED_NAMESPACE
0035 {
0036 namespace Detail
0037 {
0038 /**\internal
0039  * Break the recursion of the function below.
0040  */
0041 template <typename T> constexpr T max(T a) { return a; }
0042 /**\internal
0043  * \returns the maximum of all specified arguments.
0044  */
0045 template <typename T, typename... Ts> constexpr T max(T a, T b, Ts... rest)
0046 {
0047     return a > b ? max(a, rest...) : max(b, rest...);
0048 }
0049 }  // namespace Detail
0050 namespace Common
0051 {
0052 template <std::size_t> Vc_INTRINSIC void *aligned_malloc(std::size_t);
0053 Vc_ALWAYS_INLINE void free(void *);
0054 }  // namespace Common
0055
0056 /**
0057  * \ingroup Utilities
0058  *
0059  * Helper class to ensure a given alignment.
0060  *
0061  * This class reimplements the \c new and \c delete operators to align objects allocated
0062  * on the heap suitably with the specified alignment \c Alignment.
0063  *
0064  * \see Vc::VectorAlignedBase
0065  * \see Vc::MemoryAlignedBase
0066  */
0067 template <std::size_t Alignment> struct alignas(Alignment) AlignedBase
0068 {
0069     Vc_FREE_STORE_OPERATORS_ALIGNED(Alignment);
0070 };
0071
0072 /**
0073  * \ingroup Utilities
0074  *
0075  * Helper type to ensure suitable alignment for any Vc::Vector<T> type (using the default
0076  * VectorAbi).
0077  *
0078  * This class reimplements the \c new and \c delete operators to align objects allocated
0079  * on the heap suitably for objects of Vc::Vector<T> type. This is necessary since the
0080  * standard \c new operator does not adhere to the alignment requirements of the type.
0081  *
0082  * \see Vc::VectorAlignedBaseT
0083  * \see Vc::MemoryAlignedBase
0084  * \see Vc::AlignedBase
0085  */
0086 using VectorAlignedBase = AlignedBase<
0087     Detail::max(alignof(Vector<float>), alignof(Vector<double>), alignof(Vector<ullong>),
0088                 alignof(Vector<llong>), alignof(Vector<ulong>), alignof(Vector<long>),
0089                 alignof(Vector<uint>), alignof(Vector<int>), alignof(Vector<ushort>),
0090                 alignof(Vector<short>), alignof(Vector<uchar>), alignof(Vector<schar>))>;
0091
0092 /**
0093  * \ingroup Utilities
0094  * Variant of the above type ensuring suitable alignment only for the specified vector
0095  * type \p V.
0096  *
0097  * \see Vc::VectorAlignedBase
0098  * \see Vc::MemoryAlignedBaseT
0099  */
0100 template <typename V> using VectorAlignedBaseT = AlignedBase<alignof(V)>;
0101
0102 /**
0103  * \ingroup Utilities
0104  *
0105  * Helper class to ensure suitable alignment for arrays of scalar objects for any
0106  * Vc::Vector<T> type (using the default VectorAbi).
0107  *
0108  * This class reimplements the \c new and \c delete operators to align objects allocated
0109  * on the heap suitably for arrays of type \p Vc::Vector<T>::EntryType. Subsequent load
0110  * and store operations are safe to use the aligned variant.
0111  *
0112  * \see Vc::MemoryAlignedBaseT
0113  * \see Vc::VectorAlignedBase
0114  * \see Vc::AlignedBase
0115  */
0116 using MemoryAlignedBase = AlignedBase<
0117     Detail::max(Vector<float>::MemoryAlignment, Vector<double>::MemoryAlignment,
0118                 Vector<ullong>::MemoryAlignment, Vector<llong>::MemoryAlignment,
0119                 Vector<ulong>::MemoryAlignment, Vector<long>::MemoryAlignment,
0120                 Vector<uint>::MemoryAlignment, Vector<int>::MemoryAlignment,
0121                 Vector<ushort>::MemoryAlignment, Vector<short>::MemoryAlignment,
0122                 Vector<uchar>::MemoryAlignment, Vector<schar>::MemoryAlignment)>;
0123
0124 /**
0125  * \ingroup Utilities
0126  * Variant of the above type ensuring suitable alignment only for the specified vector
0127  * type \p V.
0128  *
0129  * \see Vc::MemoryAlignedBase
0130  * \see Vc::VectorAlignedBaseT
0131  */
0132 template <typename V> using MemoryAlignedBaseT = AlignedBase<V::MemoryAlignment>;
0133 }
0134
0135 #endif  // VC_COMMON_ALIGNEDBASE_H_
0136
0137 // vim: foldmethod=marker