memory.h

/*  This file is part of the Vc library. {{{
Copyright © 2009-2015 Matthias Kretz <kretz@kde.org>

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.
    * Neither the names of contributing organizations nor the
      names of its contributors may be used to endorse or promote products
      derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
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(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

}}}*/

#ifndef VC_COMMON_MEMORY_H_
#define VC_COMMON_MEMORY_H_

#include "memorybase.h"
#include <assert.h>
#include <algorithm>
#include <cstring>
#include <cstddef>
#include <initializer_list>
#include "memoryfwd.h"
#include "malloc.h"
#include "macros.h"

namespace Vc_VERSIONED_NAMESPACE
{
namespace Common
{
template<typename V, size_t Size> struct _MemorySizeCalculation
{
    enum AlignmentCalculations {
        Alignment = V::Size,
        AlignmentMask = Alignment - 1,
        MaskedSize = Size & AlignmentMask,
        Padding = Alignment - MaskedSize,
        PaddedSize = MaskedSize == 0 ? Size : Size + Padding
    };
};

template <typename V, size_t Size1, size_t Size2, bool InitPadding>
#ifdef Vc_RECURSIVE_MEMORY
class Memory : public MemoryBase<V, Memory<V, Size1, Size2, InitPadding>, 2,
                                 Memory<V, Size2, 0, InitPadding>>
#else
class Memory : public AlignedBase<V::MemoryAlignment>,
               public MemoryBase<V, Memory<V, Size1, Size2, InitPadding>, 2,
                                 Memory<V, Size2, 0, false>>
#endif
{
public:
    typedef typename V::EntryType EntryType;

private:
#ifdef Vc_RECURSIVE_MEMORY
    using RowMemory = Memory<V, Size2, 0, InitPadding>;
#else
    using RowMemory = Memory<V, Size2, 0, false>;
#endif
    typedef MemoryBase<V, Memory<V, Size1, Size2, InitPadding>, 2, RowMemory> Base;
    friend class MemoryBase<V, Memory<V, Size1, Size2, InitPadding>, 2, RowMemory>;
    friend class MemoryDimensionBase<V, Memory<V, Size1, Size2, InitPadding>, 2,
                                     RowMemory>;
    enum : size_t {
        Alignment = V::MemoryAlignment,
        PaddedSize2 = _MemorySizeCalculation<V, Size2>::PaddedSize
    };
    alignas(static_cast<size_t>(Alignment))  // GCC complains about 'is not an
                                             // integer constant' unless the
                                             // static_cast is present
#ifdef Vc_RECURSIVE_MEMORY
        RowMemory m_mem[Size1];
#else
        EntryType m_mem[Size1][PaddedSize2];
#endif

        public:
            using Base::vector;
            enum Constants {
                RowCount = Size1,
                VectorsCount = PaddedSize2 / V::Size
            };

#ifdef Vc_RECURSIVE_MEMORY
            Memory() = default;
#else
            Memory()
            {
                if (InitPadding) {
                    if (Size1 > 32)
                    for (size_t i = 0; i < Size1; ++i) {
                        V::Zero().store(&m_mem[i][PaddedSize2 - V::Size], Vc::Streaming);
                    }
                }
            }
#endif

            static constexpr size_t rowsCount() { return RowCount; }
            static constexpr size_t entriesCount() { return Size1 * Size2; }
            static constexpr size_t vectorsCount() { return VectorsCount * Size1; }

            template<typename Parent, typename RM>
            Vc_ALWAYS_INLINE Memory &operator=(const MemoryBase<V, Parent, 2, RM> &rhs) {
                assert(vectorsCount() == rhs.vectorsCount());
                Detail::copyVectors(*this, rhs);
                return *this;
            }

            Vc_ALWAYS_INLINE Memory &operator=(const Memory &rhs) {
                Detail::copyVectors(*this, rhs);
                return *this;
            }

            inline Memory &operator=(const V &v) {
                for (size_t i = 0; i < vectorsCount(); ++i) {
                    vector(i) = v;
                }
                return *this;
            }
};

template <typename V, size_t Size, bool InitPadding>
class Memory<V, Size, 0u, InitPadding> :
#ifndef Vc_RECURSIVE_MEMORY
    public AlignedBase<V::MemoryAlignment>,
#endif
    public MemoryBase<V, Memory<V, Size, 0u, InitPadding>, 1, void>
    {
        public:
            typedef typename V::EntryType EntryType;
        private:
            typedef MemoryBase<V, Memory<V, Size, 0u, InitPadding>, 1, void> Base;
            friend class MemoryBase<V, Memory<V, Size, 0u, InitPadding>, 1, void>;
            friend class MemoryDimensionBase<V, Memory<V, Size, 0u, InitPadding>, 1, void>;
            enum : size_t {
                Alignment = V::MemoryAlignment,     // in Bytes
                MaskedSize = Size & (V::Size - 1),  // the fraction of Size that exceeds
                                                    // an integral multiple of V::Size
                Padding = V::Size - MaskedSize,
                PaddedSize = MaskedSize == 0 ? Size : Size + Padding
            };
            alignas(static_cast<size_t>(Alignment))  // GCC complains about 'is not an
                                                     // integer constant' unless the
                                                     // static_cast is present
                EntryType m_mem[PaddedSize];

        public:
            using Base::vector;
            enum Constants {
                EntriesCount = Size,
                VectorsCount = PaddedSize / V::Size
            };

            Memory()
            {
                if (InitPadding) {
                    Base::lastVector() = V::Zero();
                }
            }

            Memory(std::initializer_list<EntryType> init)
            {
                Vc_ASSERT(init.size() <= Size);
                Base::lastVector() = V::Zero();
                std::copy(init.begin(), init.end(), &m_mem[0]);
            }

            static Vc_ALWAYS_INLINE Vc_CONST Memory<V, Size, 0u, false> &fromRawData(EntryType *ptr)
            {
                // DANGER! This placement new has to use the right address. If the compiler decides
                // RowMemory requires padding before the actual data then the address has to be adjusted
                // accordingly
                char *addr = reinterpret_cast<char *>(ptr);
                typedef Memory<V, Size, 0u, false> MM;
                addr -= Vc_OFFSETOF(MM, m_mem);
                return *new(addr) MM;
            }

            static constexpr size_t entriesCount() { return EntriesCount; }

            static constexpr size_t vectorsCount() { return VectorsCount; }

            inline Memory(const Memory &rhs)
            {
                Detail::copyVectors(*this, rhs);
            }

            template <size_t S> inline Memory(const Memory<V, S> &rhs)
            {
                assert(vectorsCount() == rhs.vectorsCount());
                Detail::copyVectors(*this, rhs);
            }

            inline Memory &operator=(const Memory &rhs)
            {
                Detail::copyVectors(*this, rhs);
                return *this;
            }

            template <size_t S> inline Memory &operator=(const Memory<V, S> &rhs)
            {
                assert(vectorsCount() == rhs.vectorsCount());
                Detail::copyVectors(*this, rhs);
                return *this;
            }

            Vc_ALWAYS_INLINE Memory &operator=(const EntryType *rhs) {
                std::memcpy(m_mem, rhs, entriesCount() * sizeof(EntryType));
                return *this;
            }
            inline Memory &operator=(const V &v) {
                for (size_t i = 0; i < vectorsCount(); ++i) {
                    vector(i) = v;
                }
                return *this;
            }
    };

    template<typename V> class Memory<V, 0u, 0u, true> : public MemoryBase<V, Memory<V, 0u, 0u, true>, 1, void>
    {
        public:
            typedef typename V::EntryType EntryType;
        private:
            typedef MemoryBase<V, Memory<V>, 1, void> Base;
            friend class MemoryBase<V, Memory<V>, 1, void>;
            friend class MemoryDimensionBase<V, Memory<V>, 1, void>;
        enum InternalConstants {
            Alignment = V::Size,
            AlignmentMask = Alignment - 1
        };
        size_t m_entriesCount;
        size_t m_vectorsCount;
        EntryType *m_mem;
        size_t calcPaddedEntriesCount(size_t x)
        {
            size_t masked = x & AlignmentMask;
            return (masked == 0 ? x : x + (Alignment - masked));
        }
    public:
        using Base::vector;

        Vc_ALWAYS_INLINE Memory(size_t size)
            : m_entriesCount(size),
            m_vectorsCount(calcPaddedEntriesCount(m_entriesCount)),
            m_mem(Vc::malloc<EntryType, Vc::AlignOnVector>(m_vectorsCount))
        {
            m_vectorsCount /= V::Size;
            Base::lastVector() = V::Zero();
        }

        template<typename Parent, typename RM>
        Vc_ALWAYS_INLINE Memory(const MemoryBase<V, Parent, 1, RM> &rhs)
            : m_entriesCount(rhs.entriesCount()),
            m_vectorsCount(rhs.vectorsCount()),
            m_mem(Vc::malloc<EntryType, Vc::AlignOnVector>(m_vectorsCount * V::Size))
        {
            Detail::copyVectors(*this, rhs);
        }

        Vc_ALWAYS_INLINE Memory(const Memory &rhs)
            : m_entriesCount(rhs.entriesCount()),
            m_vectorsCount(rhs.vectorsCount()),
            m_mem(Vc::malloc<EntryType, Vc::AlignOnVector>(m_vectorsCount * V::Size))
        {
            Detail::copyVectors(*this, rhs);
        }

        Vc_ALWAYS_INLINE ~Memory()
        {
            Vc::free(m_mem);
        }

        inline void swap(Memory &rhs) {
            std::swap(m_mem, rhs.m_mem);
            std::swap(m_entriesCount, rhs.m_entriesCount);
            std::swap(m_vectorsCount, rhs.m_vectorsCount);
        }

        Vc_ALWAYS_INLINE Vc_PURE size_t entriesCount() const { return m_entriesCount; }

        Vc_ALWAYS_INLINE Vc_PURE size_t vectorsCount() const { return m_vectorsCount; }

        template<typename Parent, typename RM>
        Vc_ALWAYS_INLINE Memory &operator=(const MemoryBase<V, Parent, 1, RM> &rhs) {
            assert(vectorsCount() == rhs.vectorsCount());
            Detail::copyVectors(*this, rhs);
            return *this;
        }

        Vc_ALWAYS_INLINE Memory &operator=(const Memory &rhs) {
            assert(vectorsCount() == rhs.vectorsCount());
            Detail::copyVectors(*this, rhs);
            return *this;
        }

        Vc_ALWAYS_INLINE Memory &operator=(const EntryType *rhs) {
            std::memcpy(m_mem, rhs, entriesCount() * sizeof(EntryType));
            return *this;
        }
};

Vc_ALWAYS_INLINE void prefetchForOneRead(const void *addr)
{
    Vc::Detail::prefetchForOneRead(addr, VectorAbi::Best<float>());
}

Vc_ALWAYS_INLINE void prefetchForModify(const void *addr)
{
    Vc::Detail::prefetchForModify(addr, VectorAbi::Best<float>());
}

Vc_ALWAYS_INLINE void prefetchClose(const void *addr)
{
    Vc::Detail::prefetchClose(addr, VectorAbi::Best<float>());
}

Vc_ALWAYS_INLINE void prefetchMid(const void *addr)
{
    Vc::Detail::prefetchMid(addr, VectorAbi::Best<float>());
}

Vc_ALWAYS_INLINE void prefetchFar(const void *addr)
{
    Vc::Detail::prefetchFar(addr, VectorAbi::Best<float>());
}
}  // namespace Common

using Common::Memory;
using Common::prefetchForOneRead;
using Common::prefetchForModify;
using Common::prefetchClose;
using Common::prefetchMid;
using Common::prefetchFar;
}  // namespace Vc

namespace std
{
    template<typename V> Vc_ALWAYS_INLINE void swap(Vc::Memory<V> &a, Vc::Memory<V> &b) { a.swap(b); }
} // namespace std

#endif // VC_COMMON_MEMORY_H_