1 // This file is part of Eigen, a lightweight C++ template library 2 // for linear algebra. 3 // 4 // Copyright (C) 2009-2010 Gael Guennebaud <gael.guennebaud@inria.fr> 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_SELFCWISEBINARYOP_H 11 #define EIGEN_SELFCWISEBINARYOP_H 12 13 namespace Eigen { 14 15 /** \class SelfCwiseBinaryOp 16 * \ingroup Core_Module 17 * 18 * \internal 19 * 20 * \brief Internal helper class for optimizing operators like +=, -= 21 * 22 * This is a pseudo expression class re-implementing the copyCoeff/copyPacket 23 * method to directly performs a +=/-= operations in an optimal way. In particular, 24 * this allows to make sure that the input/output data are loaded only once using 25 * aligned packet loads. 26 * 27 * \sa class SwapWrapper for a similar trick. 28 */ 29 30 namespace internal { 31 template<typename BinaryOp, typename Lhs, typename Rhs> 32 struct traits<SelfCwiseBinaryOp<BinaryOp,Lhs,Rhs> > 33 : traits<CwiseBinaryOp<BinaryOp,Lhs,Rhs> > 34 { 35 enum { 36 // Note that it is still a good idea to preserve the DirectAccessBit 37 // so that assign can correctly align the data. 38 Flags = traits<CwiseBinaryOp<BinaryOp,Lhs,Rhs> >::Flags | (Lhs::Flags&DirectAccessBit) | (Lhs::Flags&LvalueBit), 39 OuterStrideAtCompileTime = Lhs::OuterStrideAtCompileTime, 40 InnerStrideAtCompileTime = Lhs::InnerStrideAtCompileTime 41 }; 42 }; 43 } 44 45 template<typename BinaryOp, typename Lhs, typename Rhs> class SelfCwiseBinaryOp 46 : public internal::dense_xpr_base< SelfCwiseBinaryOp<BinaryOp, Lhs, Rhs> >::type 47 { 48 public: 49 50 typedef typename internal::dense_xpr_base<SelfCwiseBinaryOp>::type Base; 51 EIGEN_DENSE_PUBLIC_INTERFACE(SelfCwiseBinaryOp) 52 53 typedef typename internal::packet_traits<Scalar>::type Packet; 54 55 inline SelfCwiseBinaryOp(Lhs& xpr, const BinaryOp& func = BinaryOp()) : m_matrix(xpr), m_functor(func) {} 56 57 inline Index rows() const { return m_matrix.rows(); } 58 inline Index cols() const { return m_matrix.cols(); } 59 inline Index outerStride() const { return m_matrix.outerStride(); } 60 inline Index innerStride() const { return m_matrix.innerStride(); } 61 inline const Scalar* data() const { return m_matrix.data(); } 62 63 // note that this function is needed by assign to correctly align loads/stores 64 // TODO make Assign use .data() 65 inline Scalar& coeffRef(Index row, Index col) 66 { 67 EIGEN_STATIC_ASSERT_LVALUE(Lhs) 68 return m_matrix.const_cast_derived().coeffRef(row, col); 69 } 70 inline const Scalar& coeffRef(Index row, Index col) const 71 { 72 return m_matrix.coeffRef(row, col); 73 } 74 75 // note that this function is needed by assign to correctly align loads/stores 76 // TODO make Assign use .data() 77 inline Scalar& coeffRef(Index index) 78 { 79 EIGEN_STATIC_ASSERT_LVALUE(Lhs) 80 return m_matrix.const_cast_derived().coeffRef(index); 81 } 82 inline const Scalar& coeffRef(Index index) const 83 { 84 return m_matrix.const_cast_derived().coeffRef(index); 85 } 86 87 template<typename OtherDerived> 88 void copyCoeff(Index row, Index col, const DenseBase<OtherDerived>& other) 89 { 90 OtherDerived& _other = other.const_cast_derived(); 91 eigen_internal_assert(row >= 0 && row < rows() 92 && col >= 0 && col < cols()); 93 Scalar& tmp = m_matrix.coeffRef(row,col); 94 tmp = m_functor(tmp, _other.coeff(row,col)); 95 } 96 97 template<typename OtherDerived> 98 void copyCoeff(Index index, const DenseBase<OtherDerived>& other) 99 { 100 OtherDerived& _other = other.const_cast_derived(); 101 eigen_internal_assert(index >= 0 && index < m_matrix.size()); 102 Scalar& tmp = m_matrix.coeffRef(index); 103 tmp = m_functor(tmp, _other.coeff(index)); 104 } 105 106 template<typename OtherDerived, int StoreMode, int LoadMode> 107 void copyPacket(Index row, Index col, const DenseBase<OtherDerived>& other) 108 { 109 OtherDerived& _other = other.const_cast_derived(); 110 eigen_internal_assert(row >= 0 && row < rows() 111 && col >= 0 && col < cols()); 112 m_matrix.template writePacket<StoreMode>(row, col, 113 m_functor.packetOp(m_matrix.template packet<StoreMode>(row, col),_other.template packet<LoadMode>(row, col)) ); 114 } 115 116 template<typename OtherDerived, int StoreMode, int LoadMode> 117 void copyPacket(Index index, const DenseBase<OtherDerived>& other) 118 { 119 OtherDerived& _other = other.const_cast_derived(); 120 eigen_internal_assert(index >= 0 && index < m_matrix.size()); 121 m_matrix.template writePacket<StoreMode>(index, 122 m_functor.packetOp(m_matrix.template packet<StoreMode>(index),_other.template packet<LoadMode>(index)) ); 123 } 124 125 // reimplement lazyAssign to handle complex *= real 126 // see CwiseBinaryOp ctor for details 127 template<typename RhsDerived> 128 EIGEN_STRONG_INLINE SelfCwiseBinaryOp& lazyAssign(const DenseBase<RhsDerived>& rhs) 129 { 130 EIGEN_STATIC_ASSERT_SAME_MATRIX_SIZE(Lhs,RhsDerived) 131 EIGEN_CHECK_BINARY_COMPATIBILIY(BinaryOp,typename Lhs::Scalar,typename RhsDerived::Scalar); 132 133 #ifdef EIGEN_DEBUG_ASSIGN 134 internal::assign_traits<SelfCwiseBinaryOp, RhsDerived>::debug(); 135 #endif 136 eigen_assert(rows() == rhs.rows() && cols() == rhs.cols()); 137 internal::assign_impl<SelfCwiseBinaryOp, RhsDerived>::run(*this,rhs.derived()); 138 #ifndef EIGEN_NO_DEBUG 139 this->checkTransposeAliasing(rhs.derived()); 140 #endif 141 return *this; 142 } 143 144 // overloaded to honor evaluation of special matrices 145 // maybe another solution would be to not use SelfCwiseBinaryOp 146 // at first... 147 SelfCwiseBinaryOp& operator=(const Rhs& _rhs) 148 { 149 typename internal::nested<Rhs>::type rhs(_rhs); 150 return Base::operator=(rhs); 151 } 152 153 Lhs& expression() const 154 { 155 return m_matrix; 156 } 157 158 const BinaryOp& functor() const 159 { 160 return m_functor; 161 } 162 163 protected: 164 Lhs& m_matrix; 165 const BinaryOp& m_functor; 166 167 private: 168 SelfCwiseBinaryOp& operator=(const SelfCwiseBinaryOp&); 169 }; 170 171 template<typename Derived> 172 inline Derived& DenseBase<Derived>::operator*=(const Scalar& other) 173 { 174 typedef typename Derived::PlainObject PlainObject; 175 SelfCwiseBinaryOp<internal::scalar_product_op<Scalar>, Derived, typename PlainObject::ConstantReturnType> tmp(derived()); 176 tmp = PlainObject::Constant(rows(),cols(),other); 177 return derived(); 178 } 179 180 template<typename Derived> 181 inline Derived& DenseBase<Derived>::operator/=(const Scalar& other) 182 { 183 typedef typename internal::conditional<NumTraits<Scalar>::IsInteger, 184 internal::scalar_quotient_op<Scalar>, 185 internal::scalar_product_op<Scalar> >::type BinOp; 186 typedef typename Derived::PlainObject PlainObject; 187 SelfCwiseBinaryOp<BinOp, Derived, typename PlainObject::ConstantReturnType> tmp(derived()); 188 Scalar actual_other; 189 if(NumTraits<Scalar>::IsInteger) actual_other = other; 190 else actual_other = Scalar(1)/other; 191 tmp = PlainObject::Constant(rows(),cols(), actual_other); 192 return derived(); 193 } 194 195 } // end namespace Eigen 196 197 #endif // EIGEN_SELFCWISEBINARYOP_H 198