cart-elc

Source code for CART-ELC
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GeneralProduct.h (21679B)


      1 // This file is part of Eigen, a lightweight C++ template library
      2 // for linear algebra.
      3 //
      4 // Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com>
      5 // Copyright (C) 2008-2011 Gael Guennebaud <gael.guennebaud@inria.fr>
      6 //
      7 // This Source Code Form is subject to the terms of the Mozilla
      8 // Public License v. 2.0. If a copy of the MPL was not distributed
      9 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
     10 
     11 #ifndef EIGEN_GENERAL_PRODUCT_H
     12 #define EIGEN_GENERAL_PRODUCT_H
     13 
     14 namespace Eigen {
     15 
     16 enum {
     17   Large = 2,
     18   Small = 3
     19 };
     20 
     21 // Define the threshold value to fallback from the generic matrix-matrix product
     22 // implementation (heavy) to the lightweight coeff-based product one.
     23 // See generic_product_impl<Lhs,Rhs,DenseShape,DenseShape,GemmProduct>
     24 // in products/GeneralMatrixMatrix.h for more details.
     25 // TODO This threshold should also be used in the compile-time selector below.
     26 #ifndef EIGEN_GEMM_TO_COEFFBASED_THRESHOLD
     27 // This default value has been obtained on a Haswell architecture.
     28 #define EIGEN_GEMM_TO_COEFFBASED_THRESHOLD 20
     29 #endif
     30 
     31 namespace internal {
     32 
     33 template<int Rows, int Cols, int Depth> struct product_type_selector;
     34 
     35 template<int Size, int MaxSize> struct product_size_category
     36 {
     37   enum {
     38     #ifndef EIGEN_GPU_COMPILE_PHASE
     39     is_large = MaxSize == Dynamic ||
     40                Size >= EIGEN_CACHEFRIENDLY_PRODUCT_THRESHOLD ||
     41                (Size==Dynamic && MaxSize>=EIGEN_CACHEFRIENDLY_PRODUCT_THRESHOLD),
     42     #else
     43     is_large = 0,
     44     #endif
     45     value = is_large  ? Large
     46           : Size == 1 ? 1
     47                       : Small
     48   };
     49 };
     50 
     51 template<typename Lhs, typename Rhs> struct product_type
     52 {
     53   typedef typename remove_all<Lhs>::type _Lhs;
     54   typedef typename remove_all<Rhs>::type _Rhs;
     55   enum {
     56     MaxRows = traits<_Lhs>::MaxRowsAtCompileTime,
     57     Rows    = traits<_Lhs>::RowsAtCompileTime,
     58     MaxCols = traits<_Rhs>::MaxColsAtCompileTime,
     59     Cols    = traits<_Rhs>::ColsAtCompileTime,
     60     MaxDepth = EIGEN_SIZE_MIN_PREFER_FIXED(traits<_Lhs>::MaxColsAtCompileTime,
     61                                            traits<_Rhs>::MaxRowsAtCompileTime),
     62     Depth = EIGEN_SIZE_MIN_PREFER_FIXED(traits<_Lhs>::ColsAtCompileTime,
     63                                         traits<_Rhs>::RowsAtCompileTime)
     64   };
     65 
     66   // the splitting into different lines of code here, introducing the _select enums and the typedef below,
     67   // is to work around an internal compiler error with gcc 4.1 and 4.2.
     68 private:
     69   enum {
     70     rows_select = product_size_category<Rows,MaxRows>::value,
     71     cols_select = product_size_category<Cols,MaxCols>::value,
     72     depth_select = product_size_category<Depth,MaxDepth>::value
     73   };
     74   typedef product_type_selector<rows_select, cols_select, depth_select> selector;
     75 
     76 public:
     77   enum {
     78     value = selector::ret,
     79     ret = selector::ret
     80   };
     81 #ifdef EIGEN_DEBUG_PRODUCT
     82   static void debug()
     83   {
     84       EIGEN_DEBUG_VAR(Rows);
     85       EIGEN_DEBUG_VAR(Cols);
     86       EIGEN_DEBUG_VAR(Depth);
     87       EIGEN_DEBUG_VAR(rows_select);
     88       EIGEN_DEBUG_VAR(cols_select);
     89       EIGEN_DEBUG_VAR(depth_select);
     90       EIGEN_DEBUG_VAR(value);
     91   }
     92 #endif
     93 };
     94 
     95 /* The following allows to select the kind of product at compile time
     96  * based on the three dimensions of the product.
     97  * This is a compile time mapping from {1,Small,Large}^3 -> {product types} */
     98 // FIXME I'm not sure the current mapping is the ideal one.
     99 template<int M, int N>  struct product_type_selector<M,N,1>              { enum { ret = OuterProduct }; };
    100 template<int M>         struct product_type_selector<M, 1, 1>            { enum { ret = LazyCoeffBasedProductMode }; };
    101 template<int N>         struct product_type_selector<1, N, 1>            { enum { ret = LazyCoeffBasedProductMode }; };
    102 template<int Depth>     struct product_type_selector<1,    1,    Depth>  { enum { ret = InnerProduct }; };
    103 template<>              struct product_type_selector<1,    1,    1>      { enum { ret = InnerProduct }; };
    104 template<>              struct product_type_selector<Small,1,    Small>  { enum { ret = CoeffBasedProductMode }; };
    105 template<>              struct product_type_selector<1,    Small,Small>  { enum { ret = CoeffBasedProductMode }; };
    106 template<>              struct product_type_selector<Small,Small,Small>  { enum { ret = CoeffBasedProductMode }; };
    107 template<>              struct product_type_selector<Small, Small, 1>    { enum { ret = LazyCoeffBasedProductMode }; };
    108 template<>              struct product_type_selector<Small, Large, 1>    { enum { ret = LazyCoeffBasedProductMode }; };
    109 template<>              struct product_type_selector<Large, Small, 1>    { enum { ret = LazyCoeffBasedProductMode }; };
    110 template<>              struct product_type_selector<1,    Large,Small>  { enum { ret = CoeffBasedProductMode }; };
    111 template<>              struct product_type_selector<1,    Large,Large>  { enum { ret = GemvProduct }; };
    112 template<>              struct product_type_selector<1,    Small,Large>  { enum { ret = CoeffBasedProductMode }; };
    113 template<>              struct product_type_selector<Large,1,    Small>  { enum { ret = CoeffBasedProductMode }; };
    114 template<>              struct product_type_selector<Large,1,    Large>  { enum { ret = GemvProduct }; };
    115 template<>              struct product_type_selector<Small,1,    Large>  { enum { ret = CoeffBasedProductMode }; };
    116 template<>              struct product_type_selector<Small,Small,Large>  { enum { ret = GemmProduct }; };
    117 template<>              struct product_type_selector<Large,Small,Large>  { enum { ret = GemmProduct }; };
    118 template<>              struct product_type_selector<Small,Large,Large>  { enum { ret = GemmProduct }; };
    119 template<>              struct product_type_selector<Large,Large,Large>  { enum { ret = GemmProduct }; };
    120 template<>              struct product_type_selector<Large,Small,Small>  { enum { ret = CoeffBasedProductMode }; };
    121 template<>              struct product_type_selector<Small,Large,Small>  { enum { ret = CoeffBasedProductMode }; };
    122 template<>              struct product_type_selector<Large,Large,Small>  { enum { ret = GemmProduct }; };
    123 
    124 } // end namespace internal
    125 
    126 /***********************************************************************
    127 *  Implementation of Inner Vector Vector Product
    128 ***********************************************************************/
    129 
    130 // FIXME : maybe the "inner product" could return a Scalar
    131 // instead of a 1x1 matrix ??
    132 // Pro: more natural for the user
    133 // Cons: this could be a problem if in a meta unrolled algorithm a matrix-matrix
    134 // product ends up to a row-vector times col-vector product... To tackle this use
    135 // case, we could have a specialization for Block<MatrixType,1,1> with: operator=(Scalar x);
    136 
    137 /***********************************************************************
    138 *  Implementation of Outer Vector Vector Product
    139 ***********************************************************************/
    140 
    141 /***********************************************************************
    142 *  Implementation of General Matrix Vector Product
    143 ***********************************************************************/
    144 
    145 /*  According to the shape/flags of the matrix we have to distinghish 3 different cases:
    146  *   1 - the matrix is col-major, BLAS compatible and M is large => call fast BLAS-like colmajor routine
    147  *   2 - the matrix is row-major, BLAS compatible and N is large => call fast BLAS-like rowmajor routine
    148  *   3 - all other cases are handled using a simple loop along the outer-storage direction.
    149  *  Therefore we need a lower level meta selector.
    150  *  Furthermore, if the matrix is the rhs, then the product has to be transposed.
    151  */
    152 namespace internal {
    153 
    154 template<int Side, int StorageOrder, bool BlasCompatible>
    155 struct gemv_dense_selector;
    156 
    157 } // end namespace internal
    158 
    159 namespace internal {
    160 
    161 template<typename Scalar,int Size,int MaxSize,bool Cond> struct gemv_static_vector_if;
    162 
    163 template<typename Scalar,int Size,int MaxSize>
    164 struct gemv_static_vector_if<Scalar,Size,MaxSize,false>
    165 {
    166   EIGEN_STRONG_INLINE EIGEN_DEVICE_FUNC Scalar* data() { eigen_internal_assert(false && "should never be called"); return 0; }
    167 };
    168 
    169 template<typename Scalar,int Size>
    170 struct gemv_static_vector_if<Scalar,Size,Dynamic,true>
    171 {
    172   EIGEN_STRONG_INLINE EIGEN_DEVICE_FUNC Scalar* data() { return 0; }
    173 };
    174 
    175 template<typename Scalar,int Size,int MaxSize>
    176 struct gemv_static_vector_if<Scalar,Size,MaxSize,true>
    177 {
    178   enum {
    179     ForceAlignment  = internal::packet_traits<Scalar>::Vectorizable,
    180     PacketSize      = internal::packet_traits<Scalar>::size
    181   };
    182   #if EIGEN_MAX_STATIC_ALIGN_BYTES!=0
    183   internal::plain_array<Scalar,EIGEN_SIZE_MIN_PREFER_FIXED(Size,MaxSize),0,EIGEN_PLAIN_ENUM_MIN(AlignedMax,PacketSize)> m_data;
    184   EIGEN_STRONG_INLINE Scalar* data() { return m_data.array; }
    185   #else
    186   // Some architectures cannot align on the stack,
    187   // => let's manually enforce alignment by allocating more data and return the address of the first aligned element.
    188   internal::plain_array<Scalar,EIGEN_SIZE_MIN_PREFER_FIXED(Size,MaxSize)+(ForceAlignment?EIGEN_MAX_ALIGN_BYTES:0),0> m_data;
    189   EIGEN_STRONG_INLINE Scalar* data() {
    190     return ForceAlignment
    191             ? reinterpret_cast<Scalar*>((internal::UIntPtr(m_data.array) & ~(std::size_t(EIGEN_MAX_ALIGN_BYTES-1))) + EIGEN_MAX_ALIGN_BYTES)
    192             : m_data.array;
    193   }
    194   #endif
    195 };
    196 
    197 // The vector is on the left => transposition
    198 template<int StorageOrder, bool BlasCompatible>
    199 struct gemv_dense_selector<OnTheLeft,StorageOrder,BlasCompatible>
    200 {
    201   template<typename Lhs, typename Rhs, typename Dest>
    202   static void run(const Lhs &lhs, const Rhs &rhs, Dest& dest, const typename Dest::Scalar& alpha)
    203   {
    204     Transpose<Dest> destT(dest);
    205     enum { OtherStorageOrder = StorageOrder == RowMajor ? ColMajor : RowMajor };
    206     gemv_dense_selector<OnTheRight,OtherStorageOrder,BlasCompatible>
    207       ::run(rhs.transpose(), lhs.transpose(), destT, alpha);
    208   }
    209 };
    210 
    211 template<> struct gemv_dense_selector<OnTheRight,ColMajor,true>
    212 {
    213   template<typename Lhs, typename Rhs, typename Dest>
    214   static inline void run(const Lhs &lhs, const Rhs &rhs, Dest& dest, const typename Dest::Scalar& alpha)
    215   {
    216     typedef typename Lhs::Scalar   LhsScalar;
    217     typedef typename Rhs::Scalar   RhsScalar;
    218     typedef typename Dest::Scalar  ResScalar;
    219     typedef typename Dest::RealScalar  RealScalar;
    220     
    221     typedef internal::blas_traits<Lhs> LhsBlasTraits;
    222     typedef typename LhsBlasTraits::DirectLinearAccessType ActualLhsType;
    223     typedef internal::blas_traits<Rhs> RhsBlasTraits;
    224     typedef typename RhsBlasTraits::DirectLinearAccessType ActualRhsType;
    225   
    226     typedef Map<Matrix<ResScalar,Dynamic,1>, EIGEN_PLAIN_ENUM_MIN(AlignedMax,internal::packet_traits<ResScalar>::size)> MappedDest;
    227 
    228     ActualLhsType actualLhs = LhsBlasTraits::extract(lhs);
    229     ActualRhsType actualRhs = RhsBlasTraits::extract(rhs);
    230 
    231     ResScalar actualAlpha = combine_scalar_factors(alpha, lhs, rhs);
    232 
    233     // make sure Dest is a compile-time vector type (bug 1166)
    234     typedef typename conditional<Dest::IsVectorAtCompileTime, Dest, typename Dest::ColXpr>::type ActualDest;
    235 
    236     enum {
    237       // FIXME find a way to allow an inner stride on the result if packet_traits<Scalar>::size==1
    238       // on, the other hand it is good for the cache to pack the vector anyways...
    239       EvalToDestAtCompileTime = (ActualDest::InnerStrideAtCompileTime==1),
    240       ComplexByReal = (NumTraits<LhsScalar>::IsComplex) && (!NumTraits<RhsScalar>::IsComplex),
    241       MightCannotUseDest = ((!EvalToDestAtCompileTime) || ComplexByReal) && (ActualDest::MaxSizeAtCompileTime!=0)
    242     };
    243 
    244     typedef const_blas_data_mapper<LhsScalar,Index,ColMajor> LhsMapper;
    245     typedef const_blas_data_mapper<RhsScalar,Index,RowMajor> RhsMapper;
    246     RhsScalar compatibleAlpha = get_factor<ResScalar,RhsScalar>::run(actualAlpha);
    247 
    248     if(!MightCannotUseDest)
    249     {
    250       // shortcut if we are sure to be able to use dest directly,
    251       // this ease the compiler to generate cleaner and more optimzized code for most common cases
    252       general_matrix_vector_product
    253           <Index,LhsScalar,LhsMapper,ColMajor,LhsBlasTraits::NeedToConjugate,RhsScalar,RhsMapper,RhsBlasTraits::NeedToConjugate>::run(
    254           actualLhs.rows(), actualLhs.cols(),
    255           LhsMapper(actualLhs.data(), actualLhs.outerStride()),
    256           RhsMapper(actualRhs.data(), actualRhs.innerStride()),
    257           dest.data(), 1,
    258           compatibleAlpha);
    259     }
    260     else
    261     {
    262       gemv_static_vector_if<ResScalar,ActualDest::SizeAtCompileTime,ActualDest::MaxSizeAtCompileTime,MightCannotUseDest> static_dest;
    263 
    264       const bool alphaIsCompatible = (!ComplexByReal) || (numext::imag(actualAlpha)==RealScalar(0));
    265       const bool evalToDest = EvalToDestAtCompileTime && alphaIsCompatible;
    266 
    267       ei_declare_aligned_stack_constructed_variable(ResScalar,actualDestPtr,dest.size(),
    268                                                     evalToDest ? dest.data() : static_dest.data());
    269 
    270       if(!evalToDest)
    271       {
    272         #ifdef EIGEN_DENSE_STORAGE_CTOR_PLUGIN
    273         Index size = dest.size();
    274         EIGEN_DENSE_STORAGE_CTOR_PLUGIN
    275         #endif
    276         if(!alphaIsCompatible)
    277         {
    278           MappedDest(actualDestPtr, dest.size()).setZero();
    279           compatibleAlpha = RhsScalar(1);
    280         }
    281         else
    282           MappedDest(actualDestPtr, dest.size()) = dest;
    283       }
    284 
    285       general_matrix_vector_product
    286           <Index,LhsScalar,LhsMapper,ColMajor,LhsBlasTraits::NeedToConjugate,RhsScalar,RhsMapper,RhsBlasTraits::NeedToConjugate>::run(
    287           actualLhs.rows(), actualLhs.cols(),
    288           LhsMapper(actualLhs.data(), actualLhs.outerStride()),
    289           RhsMapper(actualRhs.data(), actualRhs.innerStride()),
    290           actualDestPtr, 1,
    291           compatibleAlpha);
    292 
    293       if (!evalToDest)
    294       {
    295         if(!alphaIsCompatible)
    296           dest.matrix() += actualAlpha * MappedDest(actualDestPtr, dest.size());
    297         else
    298           dest = MappedDest(actualDestPtr, dest.size());
    299       }
    300     }
    301   }
    302 };
    303 
    304 template<> struct gemv_dense_selector<OnTheRight,RowMajor,true>
    305 {
    306   template<typename Lhs, typename Rhs, typename Dest>
    307   static void run(const Lhs &lhs, const Rhs &rhs, Dest& dest, const typename Dest::Scalar& alpha)
    308   {
    309     typedef typename Lhs::Scalar   LhsScalar;
    310     typedef typename Rhs::Scalar   RhsScalar;
    311     typedef typename Dest::Scalar  ResScalar;
    312     
    313     typedef internal::blas_traits<Lhs> LhsBlasTraits;
    314     typedef typename LhsBlasTraits::DirectLinearAccessType ActualLhsType;
    315     typedef internal::blas_traits<Rhs> RhsBlasTraits;
    316     typedef typename RhsBlasTraits::DirectLinearAccessType ActualRhsType;
    317     typedef typename internal::remove_all<ActualRhsType>::type ActualRhsTypeCleaned;
    318 
    319     typename add_const<ActualLhsType>::type actualLhs = LhsBlasTraits::extract(lhs);
    320     typename add_const<ActualRhsType>::type actualRhs = RhsBlasTraits::extract(rhs);
    321 
    322     ResScalar actualAlpha = combine_scalar_factors(alpha, lhs, rhs);
    323 
    324     enum {
    325       // FIXME find a way to allow an inner stride on the result if packet_traits<Scalar>::size==1
    326       // on, the other hand it is good for the cache to pack the vector anyways...
    327       DirectlyUseRhs = ActualRhsTypeCleaned::InnerStrideAtCompileTime==1 || ActualRhsTypeCleaned::MaxSizeAtCompileTime==0
    328     };
    329 
    330     gemv_static_vector_if<RhsScalar,ActualRhsTypeCleaned::SizeAtCompileTime,ActualRhsTypeCleaned::MaxSizeAtCompileTime,!DirectlyUseRhs> static_rhs;
    331 
    332     ei_declare_aligned_stack_constructed_variable(RhsScalar,actualRhsPtr,actualRhs.size(),
    333         DirectlyUseRhs ? const_cast<RhsScalar*>(actualRhs.data()) : static_rhs.data());
    334 
    335     if(!DirectlyUseRhs)
    336     {
    337       #ifdef EIGEN_DENSE_STORAGE_CTOR_PLUGIN
    338       Index size = actualRhs.size();
    339       EIGEN_DENSE_STORAGE_CTOR_PLUGIN
    340       #endif
    341       Map<typename ActualRhsTypeCleaned::PlainObject>(actualRhsPtr, actualRhs.size()) = actualRhs;
    342     }
    343 
    344     typedef const_blas_data_mapper<LhsScalar,Index,RowMajor> LhsMapper;
    345     typedef const_blas_data_mapper<RhsScalar,Index,ColMajor> RhsMapper;
    346     general_matrix_vector_product
    347         <Index,LhsScalar,LhsMapper,RowMajor,LhsBlasTraits::NeedToConjugate,RhsScalar,RhsMapper,RhsBlasTraits::NeedToConjugate>::run(
    348         actualLhs.rows(), actualLhs.cols(),
    349         LhsMapper(actualLhs.data(), actualLhs.outerStride()),
    350         RhsMapper(actualRhsPtr, 1),
    351         dest.data(), dest.col(0).innerStride(), //NOTE  if dest is not a vector at compile-time, then dest.innerStride() might be wrong. (bug 1166)
    352         actualAlpha);
    353   }
    354 };
    355 
    356 template<> struct gemv_dense_selector<OnTheRight,ColMajor,false>
    357 {
    358   template<typename Lhs, typename Rhs, typename Dest>
    359   static void run(const Lhs &lhs, const Rhs &rhs, Dest& dest, const typename Dest::Scalar& alpha)
    360   {
    361     EIGEN_STATIC_ASSERT((!nested_eval<Lhs,1>::Evaluate),EIGEN_INTERNAL_COMPILATION_ERROR_OR_YOU_MADE_A_PROGRAMMING_MISTAKE);
    362     // TODO if rhs is large enough it might be beneficial to make sure that dest is sequentially stored in memory, otherwise use a temp
    363     typename nested_eval<Rhs,1>::type actual_rhs(rhs);
    364     const Index size = rhs.rows();
    365     for(Index k=0; k<size; ++k)
    366       dest += (alpha*actual_rhs.coeff(k)) * lhs.col(k);
    367   }
    368 };
    369 
    370 template<> struct gemv_dense_selector<OnTheRight,RowMajor,false>
    371 {
    372   template<typename Lhs, typename Rhs, typename Dest>
    373   static void run(const Lhs &lhs, const Rhs &rhs, Dest& dest, const typename Dest::Scalar& alpha)
    374   {
    375     EIGEN_STATIC_ASSERT((!nested_eval<Lhs,1>::Evaluate),EIGEN_INTERNAL_COMPILATION_ERROR_OR_YOU_MADE_A_PROGRAMMING_MISTAKE);
    376     typename nested_eval<Rhs,Lhs::RowsAtCompileTime>::type actual_rhs(rhs);
    377     const Index rows = dest.rows();
    378     for(Index i=0; i<rows; ++i)
    379       dest.coeffRef(i) += alpha * (lhs.row(i).cwiseProduct(actual_rhs.transpose())).sum();
    380   }
    381 };
    382 
    383 } // end namespace internal
    384 
    385 /***************************************************************************
    386 * Implementation of matrix base methods
    387 ***************************************************************************/
    388 
    389 /** \returns the matrix product of \c *this and \a other.
    390   *
    391   * \note If instead of the matrix product you want the coefficient-wise product, see Cwise::operator*().
    392   *
    393   * \sa lazyProduct(), operator*=(const MatrixBase&), Cwise::operator*()
    394   */
    395 template<typename Derived>
    396 template<typename OtherDerived>
    397 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
    398 const Product<Derived, OtherDerived>
    399 MatrixBase<Derived>::operator*(const MatrixBase<OtherDerived> &other) const
    400 {
    401   // A note regarding the function declaration: In MSVC, this function will sometimes
    402   // not be inlined since DenseStorage is an unwindable object for dynamic
    403   // matrices and product types are holding a member to store the result.
    404   // Thus it does not help tagging this function with EIGEN_STRONG_INLINE.
    405   enum {
    406     ProductIsValid =  Derived::ColsAtCompileTime==Dynamic
    407                    || OtherDerived::RowsAtCompileTime==Dynamic
    408                    || int(Derived::ColsAtCompileTime)==int(OtherDerived::RowsAtCompileTime),
    409     AreVectors = Derived::IsVectorAtCompileTime && OtherDerived::IsVectorAtCompileTime,
    410     SameSizes = EIGEN_PREDICATE_SAME_MATRIX_SIZE(Derived,OtherDerived)
    411   };
    412   // note to the lost user:
    413   //    * for a dot product use: v1.dot(v2)
    414   //    * for a coeff-wise product use: v1.cwiseProduct(v2)
    415   EIGEN_STATIC_ASSERT(ProductIsValid || !(AreVectors && SameSizes),
    416     INVALID_VECTOR_VECTOR_PRODUCT__IF_YOU_WANTED_A_DOT_OR_COEFF_WISE_PRODUCT_YOU_MUST_USE_THE_EXPLICIT_FUNCTIONS)
    417   EIGEN_STATIC_ASSERT(ProductIsValid || !(SameSizes && !AreVectors),
    418     INVALID_MATRIX_PRODUCT__IF_YOU_WANTED_A_COEFF_WISE_PRODUCT_YOU_MUST_USE_THE_EXPLICIT_FUNCTION)
    419   EIGEN_STATIC_ASSERT(ProductIsValid || SameSizes, INVALID_MATRIX_PRODUCT)
    420 #ifdef EIGEN_DEBUG_PRODUCT
    421   internal::product_type<Derived,OtherDerived>::debug();
    422 #endif
    423 
    424   return Product<Derived, OtherDerived>(derived(), other.derived());
    425 }
    426 
    427 /** \returns an expression of the matrix product of \c *this and \a other without implicit evaluation.
    428   *
    429   * The returned product will behave like any other expressions: the coefficients of the product will be
    430   * computed once at a time as requested. This might be useful in some extremely rare cases when only
    431   * a small and no coherent fraction of the result's coefficients have to be computed.
    432   *
    433   * \warning This version of the matrix product can be much much slower. So use it only if you know
    434   * what you are doing and that you measured a true speed improvement.
    435   *
    436   * \sa operator*(const MatrixBase&)
    437   */
    438 template<typename Derived>
    439 template<typename OtherDerived>
    440 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
    441 const Product<Derived,OtherDerived,LazyProduct>
    442 MatrixBase<Derived>::lazyProduct(const MatrixBase<OtherDerived> &other) const
    443 {
    444   enum {
    445     ProductIsValid =  Derived::ColsAtCompileTime==Dynamic
    446                    || OtherDerived::RowsAtCompileTime==Dynamic
    447                    || int(Derived::ColsAtCompileTime)==int(OtherDerived::RowsAtCompileTime),
    448     AreVectors = Derived::IsVectorAtCompileTime && OtherDerived::IsVectorAtCompileTime,
    449     SameSizes = EIGEN_PREDICATE_SAME_MATRIX_SIZE(Derived,OtherDerived)
    450   };
    451   // note to the lost user:
    452   //    * for a dot product use: v1.dot(v2)
    453   //    * for a coeff-wise product use: v1.cwiseProduct(v2)
    454   EIGEN_STATIC_ASSERT(ProductIsValid || !(AreVectors && SameSizes),
    455     INVALID_VECTOR_VECTOR_PRODUCT__IF_YOU_WANTED_A_DOT_OR_COEFF_WISE_PRODUCT_YOU_MUST_USE_THE_EXPLICIT_FUNCTIONS)
    456   EIGEN_STATIC_ASSERT(ProductIsValid || !(SameSizes && !AreVectors),
    457     INVALID_MATRIX_PRODUCT__IF_YOU_WANTED_A_COEFF_WISE_PRODUCT_YOU_MUST_USE_THE_EXPLICIT_FUNCTION)
    458   EIGEN_STATIC_ASSERT(ProductIsValid || SameSizes, INVALID_MATRIX_PRODUCT)
    459 
    460   return Product<Derived,OtherDerived,LazyProduct>(derived(), other.derived());
    461 }
    462 
    463 } // end namespace Eigen
    464 
    465 #endif // EIGEN_PRODUCT_H