cart-elc

Source code for CART-ELC
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TensorChipping.h (19707B)


      1 // This file is part of Eigen, a lightweight C++ template library
      2 // for linear algebra.
      3 //
      4 // Copyright (C) 2014 Benoit Steiner <benoit.steiner.goog@gmail.com>
      5 //
      6 // This Source Code Form is subject to the terms of the Mozilla
      7 // Public License v. 2.0. If a copy of the MPL was not distributed
      8 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
      9 
     10 #ifndef EIGEN_CXX11_TENSOR_TENSOR_CHIPPING_H
     11 #define EIGEN_CXX11_TENSOR_TENSOR_CHIPPING_H
     12 
     13 namespace Eigen {
     14 
     15 /** \class TensorKChippingReshaping
     16   * \ingroup CXX11_Tensor_Module
     17   *
     18   * \brief A chip is a thin slice, corresponding to a column or a row in a 2-d tensor.
     19   *
     20   *
     21   */
     22 
     23 namespace internal {
     24 template<DenseIndex DimId, typename XprType>
     25 struct traits<TensorChippingOp<DimId, XprType> > : public traits<XprType>
     26 {
     27   typedef typename XprType::Scalar Scalar;
     28   typedef traits<XprType> XprTraits;
     29   typedef typename XprTraits::StorageKind StorageKind;
     30   typedef typename XprTraits::Index Index;
     31   typedef typename XprType::Nested Nested;
     32   typedef typename remove_reference<Nested>::type _Nested;
     33   static const int NumDimensions = XprTraits::NumDimensions - 1;
     34   static const int Layout = XprTraits::Layout;
     35   typedef typename XprTraits::PointerType PointerType;
     36 };
     37 
     38 template<DenseIndex DimId, typename XprType>
     39 struct eval<TensorChippingOp<DimId, XprType>, Eigen::Dense>
     40 {
     41   typedef const TensorChippingOp<DimId, XprType> EIGEN_DEVICE_REF type;
     42 };
     43 
     44 template<DenseIndex DimId, typename XprType>
     45 struct nested<TensorChippingOp<DimId, XprType>, 1, typename eval<TensorChippingOp<DimId, XprType> >::type>
     46 {
     47   typedef TensorChippingOp<DimId, XprType> type;
     48 };
     49 
     50 template <DenseIndex DimId>
     51 struct DimensionId
     52 {
     53   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE DimensionId(DenseIndex dim) {
     54     EIGEN_UNUSED_VARIABLE(dim);
     55     eigen_assert(dim == DimId);
     56   }
     57   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE DenseIndex actualDim() const {
     58     return DimId;
     59   }
     60 };
     61 template <>
     62 struct DimensionId<Dynamic>
     63 {
     64   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE DimensionId(DenseIndex dim) : actual_dim(dim) {
     65     eigen_assert(dim >= 0);
     66   }
     67   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE DenseIndex actualDim() const {
     68     return actual_dim;
     69   }
     70  private:
     71   const DenseIndex actual_dim;
     72 };
     73 
     74 
     75 }  // end namespace internal
     76 
     77 
     78 
     79 template<DenseIndex DimId, typename XprType>
     80 class TensorChippingOp : public TensorBase<TensorChippingOp<DimId, XprType> >
     81 {
     82   public:
     83     typedef TensorBase<TensorChippingOp<DimId, XprType> > Base;
     84     typedef typename Eigen::internal::traits<TensorChippingOp>::Scalar Scalar;
     85     typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
     86     typedef typename XprType::CoeffReturnType CoeffReturnType;
     87     typedef typename Eigen::internal::nested<TensorChippingOp>::type Nested;
     88     typedef typename Eigen::internal::traits<TensorChippingOp>::StorageKind StorageKind;
     89     typedef typename Eigen::internal::traits<TensorChippingOp>::Index Index;
     90 
     91     EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE TensorChippingOp(const XprType& expr, const Index offset, const Index dim)
     92         : m_xpr(expr), m_offset(offset), m_dim(dim) {
     93     }
     94 
     95     EIGEN_DEVICE_FUNC
     96     const Index offset() const { return m_offset; }
     97     EIGEN_DEVICE_FUNC
     98     const Index dim() const { return m_dim.actualDim(); }
     99 
    100     EIGEN_DEVICE_FUNC
    101     const typename internal::remove_all<typename XprType::Nested>::type&
    102     expression() const { return m_xpr; }
    103 
    104     EIGEN_TENSOR_INHERIT_ASSIGNMENT_OPERATORS(TensorChippingOp)
    105 
    106   protected:
    107     typename XprType::Nested m_xpr;
    108     const Index m_offset;
    109     const internal::DimensionId<DimId> m_dim;
    110 };
    111 
    112 
    113 // Eval as rvalue
    114 template<DenseIndex DimId, typename ArgType, typename Device>
    115 struct TensorEvaluator<const TensorChippingOp<DimId, ArgType>, Device>
    116 {
    117   typedef TensorChippingOp<DimId, ArgType> XprType;
    118   static const int NumInputDims = internal::array_size<typename TensorEvaluator<ArgType, Device>::Dimensions>::value;
    119   static const int NumDims = NumInputDims-1;
    120   typedef typename XprType::Index Index;
    121   typedef DSizes<Index, NumDims> Dimensions;
    122   typedef typename XprType::Scalar Scalar;
    123   typedef typename XprType::CoeffReturnType CoeffReturnType;
    124   typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
    125   static const int PacketSize = PacketType<CoeffReturnType, Device>::size;
    126   typedef StorageMemory<CoeffReturnType, Device> Storage;
    127   typedef typename Storage::Type EvaluatorPointerType;
    128 
    129   enum {
    130     // Alignment can't be guaranteed at compile time since it depends on the
    131     // slice offsets.
    132     IsAligned         = false,
    133     Layout            = TensorEvaluator<ArgType, Device>::Layout,
    134     PacketAccess      = TensorEvaluator<ArgType, Device>::PacketAccess,
    135     BlockAccess       = TensorEvaluator<ArgType, Device>::BlockAccess,
    136     // Chipping of outer-most dimension is a trivial operation, because we can
    137     // read and write directly from the underlying tensor using single offset.
    138     IsOuterChipping   = (static_cast<int>(Layout) == ColMajor && DimId == NumInputDims - 1) ||
    139                         (static_cast<int>(Layout) == RowMajor && DimId == 0),
    140     // Chipping inner-most dimension.
    141     IsInnerChipping   = (static_cast<int>(Layout) == ColMajor && DimId == 0) ||
    142                         (static_cast<int>(Layout) == RowMajor && DimId == NumInputDims - 1),
    143     // Prefer block access if the underlying expression prefers it, otherwise
    144     // only if chipping is not trivial.
    145     PreferBlockAccess = TensorEvaluator<ArgType, Device>::PreferBlockAccess ||
    146                         !IsOuterChipping,
    147     CoordAccess       = false,  // to be implemented
    148     RawAccess         = false
    149   };
    150 
    151   typedef typename internal::remove_const<Scalar>::type ScalarNoConst;
    152 
    153   //===- Tensor block evaluation strategy (see TensorBlock.h) -------------===//
    154   typedef internal::TensorBlockDescriptor<NumDims, Index> TensorBlockDesc;
    155   typedef internal::TensorBlockScratchAllocator<Device> TensorBlockScratch;
    156 
    157   typedef internal::TensorBlockDescriptor<NumInputDims, Index>
    158       ArgTensorBlockDesc;
    159   typedef typename TensorEvaluator<const ArgType, Device>::TensorBlock
    160       ArgTensorBlock;
    161 
    162   typedef typename internal::TensorMaterializedBlock<ScalarNoConst, NumDims,
    163                                                      Layout, Index>
    164       TensorBlock;
    165   //===--------------------------------------------------------------------===//
    166 
    167   EIGEN_STRONG_INLINE TensorEvaluator(const XprType& op, const Device& device)
    168       : m_impl(op.expression(), device), m_dim(op.dim()), m_device(device)
    169   {
    170     EIGEN_STATIC_ASSERT((NumInputDims >= 1), YOU_MADE_A_PROGRAMMING_MISTAKE);
    171     eigen_assert(NumInputDims > m_dim.actualDim());
    172 
    173     const typename TensorEvaluator<ArgType, Device>::Dimensions& input_dims = m_impl.dimensions();
    174     eigen_assert(op.offset() < input_dims[m_dim.actualDim()]);
    175 
    176     int j = 0;
    177     for (int i = 0; i < NumInputDims; ++i) {
    178       if (i != m_dim.actualDim()) {
    179         m_dimensions[j] = input_dims[i];
    180         ++j;
    181       }
    182     }
    183 
    184     m_stride = 1;
    185     m_inputStride = 1;
    186     if (static_cast<int>(Layout) == static_cast<int>(ColMajor)) {
    187       for (int i = 0; i < m_dim.actualDim(); ++i) {
    188         m_stride *= input_dims[i];
    189         m_inputStride *= input_dims[i];
    190       }
    191     } else {
    192       for (int i = NumInputDims-1; i > m_dim.actualDim(); --i) {
    193         m_stride *= input_dims[i];
    194         m_inputStride *= input_dims[i];
    195       }
    196     }
    197     m_inputStride *= input_dims[m_dim.actualDim()];
    198     m_inputOffset = m_stride * op.offset();
    199   }
    200 
    201   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
    202 
    203   EIGEN_STRONG_INLINE bool evalSubExprsIfNeeded(EvaluatorPointerType) {
    204     m_impl.evalSubExprsIfNeeded(NULL);
    205     return true;
    206   }
    207 
    208   EIGEN_STRONG_INLINE void cleanup() {
    209     m_impl.cleanup();
    210   }
    211 
    212   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoeffReturnType coeff(Index index) const
    213   {
    214     return m_impl.coeff(srcCoeff(index));
    215   }
    216 
    217   template<int LoadMode>
    218   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE PacketReturnType packet(Index index) const
    219   {
    220     EIGEN_STATIC_ASSERT((PacketSize > 1), YOU_MADE_A_PROGRAMMING_MISTAKE)
    221     eigen_assert(index+PacketSize-1 < dimensions().TotalSize());
    222 
    223     if (isInnerChipping()) {
    224       // m_stride is equal to 1, so let's avoid the integer division.
    225       eigen_assert(m_stride == 1);
    226       Index inputIndex = index * m_inputStride + m_inputOffset;
    227       EIGEN_ALIGN_MAX typename internal::remove_const<CoeffReturnType>::type values[PacketSize];
    228       EIGEN_UNROLL_LOOP
    229       for (int i = 0; i < PacketSize; ++i) {
    230         values[i] = m_impl.coeff(inputIndex);
    231         inputIndex += m_inputStride;
    232       }
    233       PacketReturnType rslt = internal::pload<PacketReturnType>(values);
    234       return rslt;
    235     } else if (isOuterChipping()) {
    236       // m_stride is always greater than index, so let's avoid the integer division.
    237       eigen_assert(m_stride > index);
    238       return m_impl.template packet<LoadMode>(index + m_inputOffset);
    239     } else {
    240       const Index idx = index / m_stride;
    241       const Index rem = index - idx * m_stride;
    242       if (rem + PacketSize <= m_stride) {
    243         Index inputIndex = idx * m_inputStride + m_inputOffset + rem;
    244         return m_impl.template packet<LoadMode>(inputIndex);
    245       } else {
    246         // Cross the stride boundary. Fallback to slow path.
    247         EIGEN_ALIGN_MAX typename internal::remove_const<CoeffReturnType>::type values[PacketSize];
    248        EIGEN_UNROLL_LOOP
    249         for (int i = 0; i < PacketSize; ++i) {
    250           values[i] = coeff(index);
    251           ++index;
    252         }
    253         PacketReturnType rslt = internal::pload<PacketReturnType>(values);
    254         return rslt;
    255       }
    256     }
    257   }
    258 
    259   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE TensorOpCost
    260   costPerCoeff(bool vectorized) const {
    261     double cost = 0;
    262     if ((static_cast<int>(Layout) == static_cast<int>(ColMajor) &&
    263          m_dim.actualDim() == 0) ||
    264         (static_cast<int>(Layout) == static_cast<int>(RowMajor) &&
    265          m_dim.actualDim() == NumInputDims - 1)) {
    266       cost += TensorOpCost::MulCost<Index>() + TensorOpCost::AddCost<Index>();
    267     } else if ((static_cast<int>(Layout) == static_cast<int>(ColMajor) &&
    268                 m_dim.actualDim() == NumInputDims - 1) ||
    269                (static_cast<int>(Layout) == static_cast<int>(RowMajor) &&
    270                 m_dim.actualDim() == 0)) {
    271       cost += TensorOpCost::AddCost<Index>();
    272     } else {
    273       cost += 3 * TensorOpCost::MulCost<Index>() + TensorOpCost::DivCost<Index>() +
    274               3 * TensorOpCost::AddCost<Index>();
    275     }
    276 
    277     return m_impl.costPerCoeff(vectorized) +
    278            TensorOpCost(0, 0, cost, vectorized, PacketSize);
    279   }
    280 
    281   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
    282   internal::TensorBlockResourceRequirements getResourceRequirements() const {
    283     const size_t target_size = m_device.lastLevelCacheSize();
    284     return internal::TensorBlockResourceRequirements::merge(
    285         internal::TensorBlockResourceRequirements::skewed<Scalar>(target_size),
    286         m_impl.getResourceRequirements());
    287   }
    288 
    289   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE TensorBlock
    290   block(TensorBlockDesc& desc, TensorBlockScratch& scratch,
    291           bool root_of_expr_ast = false) const {
    292     const Index chip_dim = m_dim.actualDim();
    293 
    294     DSizes<Index, NumInputDims> input_block_dims;
    295     for (int i = 0; i < NumInputDims; ++i) {
    296       input_block_dims[i]
    297             = i < chip_dim ? desc.dimension(i)
    298             : i > chip_dim ? desc.dimension(i - 1)
    299             : 1;
    300     }
    301 
    302     ArgTensorBlockDesc arg_desc(srcCoeff(desc.offset()), input_block_dims);
    303 
    304     // Try to reuse destination buffer for materializing argument block.
    305     if (desc.HasDestinationBuffer()) {
    306       DSizes<Index, NumInputDims> arg_destination_strides;
    307       for (int i = 0; i < NumInputDims; ++i) {
    308       arg_destination_strides[i]
    309             = i < chip_dim ? desc.destination().strides()[i]
    310             : i > chip_dim ? desc.destination().strides()[i - 1]
    311             : 0; // for dimensions of size `1` stride should never be used.
    312       }
    313 
    314       arg_desc.template AddDestinationBuffer<Layout>(
    315           desc.destination().template data<ScalarNoConst>(),
    316           arg_destination_strides);
    317     }
    318 
    319     ArgTensorBlock arg_block = m_impl.block(arg_desc, scratch, root_of_expr_ast);
    320     if (!arg_desc.HasDestinationBuffer()) desc.DropDestinationBuffer();
    321 
    322     if (arg_block.data() != NULL) {
    323       // Forward argument block buffer if possible.
    324       return TensorBlock(arg_block.kind(), arg_block.data(),
    325                            desc.dimensions());
    326 
    327     } else {
    328       // Assign argument block expression to a buffer.
    329 
    330       // Prepare storage for the materialized chipping result.
    331       const typename TensorBlock::Storage block_storage =
    332           TensorBlock::prepareStorage(desc, scratch);
    333 
    334       typedef internal::TensorBlockAssignment<
    335           ScalarNoConst, NumInputDims, typename ArgTensorBlock::XprType, Index>
    336           TensorBlockAssignment;
    337 
    338       TensorBlockAssignment::Run(
    339           TensorBlockAssignment::target(
    340               arg_desc.dimensions(),
    341               internal::strides<Layout>(arg_desc.dimensions()),
    342               block_storage.data()),
    343           arg_block.expr());
    344 
    345       return block_storage.AsTensorMaterializedBlock();
    346     }
    347   }
    348 
    349   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE typename Storage::Type data() const {
    350     typename Storage::Type result = constCast(m_impl.data());
    351     if (isOuterChipping() && result) {
    352       return result + m_inputOffset;
    353     } else {
    354       return NULL;
    355     }
    356   }
    357 #ifdef EIGEN_USE_SYCL
    358   // binding placeholder accessors to a command group handler for SYCL
    359   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void bind(cl::sycl::handler &cgh) const {
    360     m_impl.bind(cgh);
    361   }
    362 #endif
    363 
    364  protected:
    365   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Index srcCoeff(Index index) const
    366   {
    367     Index inputIndex;
    368     if (isInnerChipping()) {
    369       // m_stride is equal to 1, so let's avoid the integer division.
    370       eigen_assert(m_stride == 1);
    371       inputIndex = index * m_inputStride + m_inputOffset;
    372     } else if (isOuterChipping()) {
    373       // m_stride is always greater than index, so let's avoid the integer
    374       // division.
    375       eigen_assert(m_stride > index);
    376       inputIndex = index + m_inputOffset;
    377     } else {
    378       const Index idx = index / m_stride;
    379       inputIndex = idx * m_inputStride + m_inputOffset;
    380       index -= idx * m_stride;
    381       inputIndex += index;
    382     }
    383     return inputIndex;
    384   }
    385 
    386   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE bool isInnerChipping() const {
    387     return IsInnerChipping ||
    388            (static_cast<int>(Layout) == ColMajor && m_dim.actualDim() == 0) ||
    389            (static_cast<int>(Layout) == RowMajor && m_dim.actualDim() == NumInputDims - 1);
    390   }
    391 
    392   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE bool isOuterChipping() const {
    393     return IsOuterChipping ||
    394            (static_cast<int>(Layout) == ColMajor && m_dim.actualDim() == NumInputDims-1) ||
    395            (static_cast<int>(Layout) == RowMajor && m_dim.actualDim() == 0);
    396   }
    397 
    398   Dimensions m_dimensions;
    399   Index m_stride;
    400   Index m_inputOffset;
    401   Index m_inputStride;
    402   TensorEvaluator<ArgType, Device> m_impl;
    403   const internal::DimensionId<DimId> m_dim;
    404   const Device EIGEN_DEVICE_REF m_device;
    405 };
    406 
    407 
    408 // Eval as lvalue
    409 template<DenseIndex DimId, typename ArgType, typename Device>
    410 struct TensorEvaluator<TensorChippingOp<DimId, ArgType>, Device>
    411   : public TensorEvaluator<const TensorChippingOp<DimId, ArgType>, Device>
    412 {
    413   typedef TensorEvaluator<const TensorChippingOp<DimId, ArgType>, Device> Base;
    414   typedef TensorChippingOp<DimId, ArgType> XprType;
    415   static const int NumInputDims = internal::array_size<typename TensorEvaluator<ArgType, Device>::Dimensions>::value;
    416   static const int NumDims = NumInputDims-1;
    417   typedef typename XprType::Index Index;
    418   typedef DSizes<Index, NumDims> Dimensions;
    419   typedef typename XprType::Scalar Scalar;
    420   typedef typename XprType::CoeffReturnType CoeffReturnType;
    421   typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
    422   static const int PacketSize = PacketType<CoeffReturnType, Device>::size;
    423 
    424   enum {
    425     IsAligned     = false,
    426     PacketAccess  = TensorEvaluator<ArgType, Device>::PacketAccess,
    427     BlockAccess   = TensorEvaluator<ArgType, Device>::RawAccess,
    428     Layout        = TensorEvaluator<ArgType, Device>::Layout,
    429     RawAccess     = false
    430   };
    431 
    432   //===- Tensor block evaluation strategy (see TensorBlock.h) -------------===//
    433   typedef internal::TensorBlockDescriptor<NumDims, Index> TensorBlockDesc;
    434   //===--------------------------------------------------------------------===//
    435 
    436   EIGEN_STRONG_INLINE TensorEvaluator(const XprType& op, const Device& device)
    437     : Base(op, device)
    438     { }
    439 
    440   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoeffReturnType& coeffRef(Index index)
    441   {
    442     return this->m_impl.coeffRef(this->srcCoeff(index));
    443   }
    444 
    445   template <int StoreMode> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
    446   void writePacket(Index index, const PacketReturnType& x)
    447   {
    448     EIGEN_STATIC_ASSERT((PacketSize > 1), YOU_MADE_A_PROGRAMMING_MISTAKE)
    449 
    450     if (this->isInnerChipping()) {
    451       // m_stride is equal to 1, so let's avoid the integer division.
    452       eigen_assert(this->m_stride == 1);
    453       EIGEN_ALIGN_MAX typename internal::remove_const<CoeffReturnType>::type values[PacketSize];
    454       internal::pstore<CoeffReturnType, PacketReturnType>(values, x);
    455       Index inputIndex = index * this->m_inputStride + this->m_inputOffset;
    456       EIGEN_UNROLL_LOOP
    457       for (int i = 0; i < PacketSize; ++i) {
    458         this->m_impl.coeffRef(inputIndex) = values[i];
    459         inputIndex += this->m_inputStride;
    460       }
    461     } else if (this->isOuterChipping()) {
    462       // m_stride is always greater than index, so let's avoid the integer division.
    463       eigen_assert(this->m_stride > index);
    464       this->m_impl.template writePacket<StoreMode>(index + this->m_inputOffset, x);
    465     } else {
    466       const Index idx = index / this->m_stride;
    467       const Index rem = index - idx * this->m_stride;
    468       if (rem + PacketSize <= this->m_stride) {
    469         const Index inputIndex = idx * this->m_inputStride + this->m_inputOffset + rem;
    470         this->m_impl.template writePacket<StoreMode>(inputIndex, x);
    471       } else {
    472         // Cross stride boundary. Fallback to slow path.
    473         EIGEN_ALIGN_MAX typename internal::remove_const<CoeffReturnType>::type values[PacketSize];
    474         internal::pstore<CoeffReturnType, PacketReturnType>(values, x);
    475         EIGEN_UNROLL_LOOP
    476         for (int i = 0; i < PacketSize; ++i) {
    477           this->coeffRef(index) = values[i];
    478           ++index;
    479         }
    480       }
    481     }
    482   }
    483 
    484   template <typename TensorBlock>
    485   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void writeBlock(
    486       const TensorBlockDesc& desc, const TensorBlock& block) {
    487     assert(this->m_impl.data() != NULL);
    488 
    489     const Index chip_dim = this->m_dim.actualDim();
    490 
    491     DSizes<Index, NumInputDims> input_block_dims;
    492     for (int i = 0; i < NumInputDims; ++i) {
    493       input_block_dims[i] = i < chip_dim ? desc.dimension(i)
    494                           : i > chip_dim ? desc.dimension(i - 1)
    495                           : 1;
    496     }
    497 
    498     typedef TensorReshapingOp<const DSizes<Index, NumInputDims>,
    499                               const typename TensorBlock::XprType>
    500         TensorBlockExpr;
    501 
    502     typedef internal::TensorBlockAssignment<Scalar, NumInputDims,
    503                                             TensorBlockExpr, Index>
    504         TensorBlockAssign;
    505 
    506     TensorBlockAssign::Run(
    507         TensorBlockAssign::target(
    508             input_block_dims,
    509             internal::strides<Layout>(this->m_impl.dimensions()),
    510             this->m_impl.data(), this->srcCoeff(desc.offset())),
    511         block.expr().reshape(input_block_dims));
    512   }
    513 };
    514 
    515 
    516 } // end namespace Eigen
    517 
    518 #endif // EIGEN_CXX11_TENSOR_TENSOR_CHIPPING_H