* resurected Flagged from Eigen2Support

* reimplement .diagonal() for ProductBase to make (A*B).diagonal() more efficient!

Eigen/src/Core/Flagged.h

@@ -0,0 +1,121 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2008 Benoit Jacob <jacob.benoit.1@gmail.com>
+//
+// Eigen is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 3 of the License, or (at your option) any later version.
+//
+// Alternatively, you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 2 of
+// the License, or (at your option) any later version.
+//
+// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License and a copy of the GNU General Public License along with
+// Eigen. If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef EIGEN_FLAGGED_H
+#define EIGEN_FLAGGED_H
+
+/** \class Flagged
+  *
+  * \brief Expression with modified flags
+  *
+  * \param ExpressionType the type of the object of which we are modifying the flags
+  * \param Added the flags added to the expression
+  * \param Removed the flags removed from the expression (has priority over Added).
+  *
+  * This class represents an expression whose flags have been modified.
+  * It is the return type of MatrixBase::flagged()
+  * and most of the time this is the only way it is used.
+  *
+  * \sa MatrixBase::flagged()
+  */
+template<typename ExpressionType, unsigned int Added, unsigned int Removed>
+struct ei_traits<Flagged<ExpressionType, Added, Removed> > : ei_traits<ExpressionType>
+{
+  enum { Flags = (ExpressionType::Flags | Added) & ~Removed };
+};
+
+template<typename ExpressionType, unsigned int Added, unsigned int Removed> class Flagged
+  : public MatrixBase<Flagged<ExpressionType, Added, Removed> >
+{
+  public:
+
+    typedef MatrixBase<Flagged> Base;
+    EIGEN_DENSE_PUBLIC_INTERFACE(Flagged)
+    typedef typename ei_meta_if<ei_must_nest_by_value<ExpressionType>::ret,
+        ExpressionType, const ExpressionType&>::ret ExpressionTypeNested;
+    typedef typename ExpressionType::InnerIterator InnerIterator;
+
+    inline Flagged(const ExpressionType& matrix) : m_matrix(matrix) {}
+
+    inline int rows() const { return m_matrix.rows(); }
+    inline int cols() const { return m_matrix.cols(); }
+    inline int stride() const { return m_matrix.stride(); }
+
+    inline const Scalar coeff(int row, int col) const
+    {
+      return m_matrix.coeff(row, col);
+    }
+
+    inline Scalar& coeffRef(int row, int col)
+    {
+      return m_matrix.const_cast_derived().coeffRef(row, col);
+    }
+
+    inline const Scalar coeff(int index) const
+    {
+      return m_matrix.coeff(index);
+    }
+
+    inline Scalar& coeffRef(int index)
+    {
+      return m_matrix.const_cast_derived().coeffRef(index);
+    }
+
+    template<int LoadMode>
+    inline const PacketScalar packet(int row, int col) const
+    {
+      return m_matrix.template packet<LoadMode>(row, col);
+    }
+
+    template<int LoadMode>
+    inline void writePacket(int row, int col, const PacketScalar& x)
+    {
+      m_matrix.const_cast_derived().template writePacket<LoadMode>(row, col, x);
+    }
+
+    template<int LoadMode>
+    inline const PacketScalar packet(int index) const
+    {
+      return m_matrix.template packet<LoadMode>(index);
+    }
+
+    template<int LoadMode>
+    inline void writePacket(int index, const PacketScalar& x)
+    {
+      m_matrix.const_cast_derived().template writePacket<LoadMode>(index, x);
+    }
+
+    const ExpressionType& _expression() const { return m_matrix; }
+
+    template<typename OtherDerived>
+    typename ExpressionType::PlainMatrixType solveTriangular(const MatrixBase<OtherDerived>& other) const;
+
+    template<typename OtherDerived>
+    void solveTriangularInPlace(const MatrixBase<OtherDerived>& other) const;
+
+  protected:
+    ExpressionTypeNested m_matrix;
+};
+
+#endif // EIGEN_FLAGGED_H

Eigen/src/Core/Product.h

@@ -54,8 +54,6 @@ enum {
   Small = Dynamic/2
 };
 
-enum { OuterProduct, InnerProduct, UnrolledProduct, GemvProduct, GemmProduct };
-
 template<typename Lhs, typename Rhs> struct ei_product_type
 {
   typedef typename ei_cleantype<Lhs>::type _Lhs;

Eigen/src/Core/ProductBase.h

@@ -25,6 +25,8 @@
 #ifndef EIGEN_PRODUCTBASE_H
 #define EIGEN_PRODUCTBASE_H
 
+enum { OuterProduct, InnerProduct, UnrolledProduct, GemvProduct, GemmProduct };
+
 /** \class ProductBase
   *
   */
@@ -69,7 +71,7 @@ class ProductBase : public MatrixBase<Derived>
   public:
     typedef MatrixBase<Derived> Base;
     EIGEN_DENSE_PUBLIC_INTERFACE(ProductBase)
-
+  protected:
     typedef typename Lhs::Nested LhsNested;
     typedef typename ei_cleantype<LhsNested>::type _LhsNested;
     typedef ei_blas_traits<_LhsNested> LhsBlasTraits;
@@ -82,6 +84,10 @@ class ProductBase : public MatrixBase<Derived>
     typedef typename RhsBlasTraits::DirectLinearAccessType ActualRhsType;
     typedef typename ei_cleantype<ActualRhsType>::type _ActualRhsType;
 
+    typedef typename ProductReturnType<Lhs,Rhs,UnrolledProduct>::Type CoeffBaseProductType;
+    typedef Flagged<CoeffBaseProductType,0,EvalBeforeNestingBit> LazyCoeffBaseProductType;
+  public:
+
     typedef typename Base::PlainMatrixType PlainMatrixType;
 
     ProductBase(const Lhs& lhs, const Rhs& rhs)
@@ -113,6 +119,26 @@ class ProductBase : public MatrixBase<Derived>
     const _LhsNested& lhs() const { return m_lhs; }
     const _RhsNested& rhs() const { return m_rhs; }
 
+    const Diagonal<LazyCoeffBaseProductType,0> diagonal() const
+    { return Diagonal<LazyCoeffBaseProductType,0>(CoeffBaseProductType(m_lhs, m_rhs)); }
+
+    Diagonal<LazyCoeffBaseProductType,0> diagonal()
+    { return Diagonal<LazyCoeffBaseProductType,0>(CoeffBaseProductType(m_lhs, m_rhs)); }
+
+    template<int Index>
+    const Diagonal<LazyCoeffBaseProductType,Index> diagonal() const
+    { return Diagonal<LazyCoeffBaseProductType,Index>(CoeffBaseProductType(m_lhs, m_rhs)); }
+
+    template<int Index>
+    Diagonal<LazyCoeffBaseProductType,Index> diagonal()
+    { return Diagonal<LazyCoeffBaseProductType,Index>(CoeffBaseProductType(m_lhs, m_rhs)); }
+
+    const Diagonal<LazyCoeffBaseProductType,Dynamic> diagonal(int index) const
+    { return Diagonal<LazyCoeffBaseProductType,Dynamic>(LazyCoeffBaseProductType(CoeffBaseProductType(m_lhs, m_rhs))).diagonal(index); }
+
+    Diagonal<LazyCoeffBaseProductType,Dynamic> diagonal(int index)
+    { return Diagonal<LazyCoeffBaseProductType,Dynamic>(LazyCoeffBaseProductType(CoeffBaseProductType(m_lhs, m_rhs))).diagonal(index); }
+
   protected:
 
     const LhsNested m_lhs;