miserable half-working state, commiting to a fork just in case, just to perfect

my day, my hard disk would die.
Will write a more detailed commit message once it's working.

14 files changed, 256 insertions, 133 deletions

diff --git a/Eigen/src/Core/Assign.h b/Eigen/src/Core/Assign.h
index 9440cebf1..174fd0080 100644
--- a/Eigen/src/Core/Assign.h
+++ b/Eigen/src/Core/Assign.h
@@ -37,19 +37,20 @@ struct ei_assign_traits
 public:
   enum {
     DstIsAligned = Derived::Flags & AlignedBit,
+    DstHasDirectAccess = Derived::Flags & DirectAccessBit,
     SrcIsAligned = OtherDerived::Flags & AlignedBit,
-    SrcAlignment = DstIsAligned && SrcIsAligned ? Aligned : Unaligned
+    JointAlignment = DstIsAligned && SrcIsAligned ? Aligned : Unaligned
   };
 
 private:
   enum {
-    InnerSize = int(Derived::Flags)&RowMajorBit
-              ? Derived::ColsAtCompileTime
-              : Derived::RowsAtCompileTime,
-    InnerMaxSize = int(Derived::Flags)&RowMajorBit
-              ? Derived::MaxColsAtCompileTime
-              : Derived::MaxRowsAtCompileTime,
-    MaxSizeAtCompileTime = ei_size_at_compile_time<Derived::MaxColsAtCompileTime,Derived::MaxRowsAtCompileTime>::ret,
+    InnerSize = int(Derived::IsVectorAtCompileTime) ? int(Derived::SizeAtCompileTime)
+              : int(Derived::Flags)&RowMajorBit ? int(Derived::ColsAtCompileTime)
+              : int(Derived::RowsAtCompileTime),
+    InnerMaxSize = int(Derived::IsVectorAtCompileTime) ? int(Derived::MaxSizeAtCompileTime)
+              : int(Derived::Flags)&RowMajorBit ? int(Derived::MaxColsAtCompileTime)
+              : int(Derived::MaxRowsAtCompileTime),
+    MaxSizeAtCompileTime = Derived::SizeAtCompileTime,
     PacketSize = ei_packet_traits<typename Derived::Scalar>::size
   };
 
@@ -60,11 +61,11 @@ private:
     MayInnerVectorize  = MightVectorize && int(InnerSize)!=Dynamic && int(InnerSize)%int(PacketSize)==0
                        && int(DstIsAligned) && int(SrcIsAligned),
     MayLinearize = StorageOrdersAgree && (int(Derived::Flags) & int(OtherDerived::Flags) & LinearAccessBit),
-    MayLinearVectorize = MightVectorize && MayLinearize
-                                        && (DstIsAligned || MaxSizeAtCompileTime == Dynamic),
+    MayLinearVectorize = MightVectorize && MayLinearize && DstHasDirectAccess
+                       && (DstIsAligned || MaxSizeAtCompileTime == Dynamic),
       /* If the destination isn't aligned, we have to do runtime checks and we don't unroll,
          so it's only good for large enough sizes. */
-    MaySliceVectorize  = MightVectorize && int(InnerMaxSize)>=3*PacketSize
+    MaySliceVectorize  = MightVectorize && DstHasDirectAccess && int(InnerMaxSize)>=3*PacketSize
       /* slice vectorization can be slow, so we only want it if the slices are big, which is
          indicated by InnerMaxSize rather than InnerSize, think of the case of a dynamic block
          in a fixed-size matrix */
@@ -108,12 +109,13 @@ public:
   {
     EIGEN_DEBUG_VAR(DstIsAligned)
     EIGEN_DEBUG_VAR(SrcIsAligned)
-    EIGEN_DEBUG_VAR(SrcAlignment)
+    EIGEN_DEBUG_VAR(JointAlignment)
     EIGEN_DEBUG_VAR(InnerSize)
     EIGEN_DEBUG_VAR(InnerMaxSize)
     EIGEN_DEBUG_VAR(PacketSize)
     EIGEN_DEBUG_VAR(StorageOrdersAgree)
     EIGEN_DEBUG_VAR(MightVectorize)
+    EIGEN_DEBUG_VAR(MayLinearize)
     EIGEN_DEBUG_VAR(MayInnerVectorize)
     EIGEN_DEBUG_VAR(MayLinearVectorize)
     EIGEN_DEBUG_VAR(MaySliceVectorize)
@@ -211,12 +213,12 @@ struct ei_assign_innervec_CompleteUnrolling
     col = int(Derived1::Flags)&RowMajorBit
         ? Index % int(Derived1::ColsAtCompileTime)
         : Index / Derived1::RowsAtCompileTime,
-    SrcAlignment = ei_assign_traits<Derived1,Derived2>::SrcAlignment
+    JointAlignment = ei_assign_traits<Derived1,Derived2>::JointAlignment
   };
 
   EIGEN_STRONG_INLINE static void run(Derived1 &dst, const Derived2 &src)
   {
-    dst.template copyPacket<Derived2, Aligned, SrcAlignment>(row, col, src);
+    dst.template copyPacket<Derived2, Aligned, JointAlignment>(row, col, src);
     ei_assign_innervec_CompleteUnrolling<Derived1, Derived2,
       Index+ei_packet_traits<typename Derived1::Scalar>::size, Stop>::run(dst, src);
   }
@@ -265,16 +267,29 @@ struct ei_assign_impl<Derived1, Derived2, DefaultTraversal, NoUnrolling>
 {
   inline static void run(Derived1 &dst, const Derived2 &src)
   {
-    const int innerSize = dst.innerSize();
-    const int outerSize = dst.outerSize();
-    for(int j = 0; j < outerSize; ++j)
-      for(int i = 0; i < innerSize; ++i)
-      {
-        if(int(Derived1::Flags)&RowMajorBit)
-          dst.copyCoeff(j, i, src);
-        else
-          dst.copyCoeff(i, j, src);
-      }
+    if(Derived1::ColsAtCompileTime == 1)
+    {
+      for(int i = 0; i < dst.rows(); ++i)
+        dst.copyCoeff(i, 0, src);
+    }
+    else if(Derived1::RowsAtCompileTime == 1)
+    {
+      for(int i = 0; i < dst.cols(); ++i)
+        dst.copyCoeff(0, i, src);
+    }
+    else
+    {
+      const int innerSize = dst.innerSize();
+      const int outerSize = dst.outerSize();
+      for(int j = 0; j < outerSize; ++j)
+        for(int i = 0; i < innerSize; ++i)
+        {
+          if(int(Derived1::Flags)&RowMajorBit)
+            dst.copyCoeff(j, i, src);
+          else
+            dst.copyCoeff(i, j, src);
+        }
+    }
   }
 };
 
@@ -418,7 +433,7 @@ struct ei_assign_impl<Derived1, Derived2, LinearVectorizedTraversal, NoUnrolling
 
     for(int index = alignedStart; index < alignedEnd; index += packetSize)
     {
-      dst.template copyPacket<Derived2, Aligned, ei_assign_traits<Derived1,Derived2>::SrcAlignment>(index, src);
+      dst.template copyPacket<Derived2, Aligned, ei_assign_traits<Derived1,Derived2>::JointAlignment>(index, src);
     }
 
     ei_unaligned_assign_impl<>::run(src,dst,alignedEnd,size);
@@ -452,7 +467,7 @@ struct ei_assign_impl<Derived1, Derived2, SliceVectorizedTraversal, NoUnrolling>
     const int packetAlignedMask = packetSize - 1;
     const int innerSize = dst.innerSize();
     const int outerSize = dst.outerSize();
-    const int alignedStep = (packetSize - dst.stride() % packetSize) & packetAlignedMask;
+    const int alignedStep = (packetSize - dst.outerStride() % packetSize) & packetAlignedMask;
     int alignedStart = ei_assign_traits<Derived1,Derived2>::DstIsAligned ? 0
                      : ei_first_aligned(&dst.coeffRef(0,0), innerSize);
 
@@ -504,6 +519,14 @@ EIGEN_STRONG_INLINE Derived& DenseBase<Derived>
   EIGEN_STATIC_ASSERT_SAME_MATRIX_SIZE(Derived,OtherDerived)
   EIGEN_STATIC_ASSERT((ei_is_same_type<typename Derived::Scalar, typename OtherDerived::Scalar>::ret),
     YOU_MIXED_DIFFERENT_NUMERIC_TYPES__YOU_NEED_TO_USE_THE_CAST_METHOD_OF_MATRIXBASE_TO_CAST_NUMERIC_TYPES_EXPLICITLY)
+  if(Derived::ColsAtCompileTime == 1)
+  {
+    ei_assert(OtherDerived::RowsAtCompileTime == 1 || other.cols() == 1);
+  }
+  if(Derived::RowsAtCompileTime == 1)
+  {
+    ei_assert(OtherDerived::ColsAtCompileTime == 1 || other.rows() == 1);
+  }
 #ifdef EIGEN_DEBUG_ASSIGN
   ei_assign_traits<Derived, OtherDerived>::debug();
 #endif
diff --git a/Eigen/src/Core/Block.h b/Eigen/src/Core/Block.h
index 3b4234c22..8a7aea91f 100644
--- a/Eigen/src/Core/Block.h
+++ b/Eigen/src/Core/Block.h
@@ -80,6 +80,20 @@ struct ei_traits<Block<MatrixType, BlockRows, BlockCols, _DirectAccessStatus> >
   };
 };
 
+template<typename MatrixType, int BlockRows, int BlockCols>
+struct ei_traits<Block<MatrixType, BlockRows, BlockCols, true> > : ei_traits<Block<MatrixType, BlockRows, BlockCols, false> >
+{
+  enum {
+    InnerStrideAtCompileTime =
+        (BlockRows==1 && !(int(MatrixType::Flags)&RowMajorBit))
+        || (BlockCols==1 && (int(MatrixType::Flags)&RowMajorBit))
+        ? MatrixType::OuterStrideAtCompileTime
+        : MatrixType::InnerStrideAtCompileTime,
+    OuterStrideAtCompileTime =
+        (BlockRows==1||BlockCols==1) ? 0 : MatrixType::OuterStrideAtCompileTime
+  };
+};
+
 template<typename MatrixType, int BlockRows, int BlockCols, int _DirectAccessStatus> class Block
   : public MatrixType::template MakeBase< Block<MatrixType, BlockRows, BlockCols, _DirectAccessStatus> >::Type
 {
@@ -196,8 +210,8 @@ template<typename MatrixType, int BlockRows, int BlockCols, int _DirectAccessSta
     #ifdef EIGEN_PARSED_BY_DOXYGEN
     /** \sa MapBase::data() */
     inline const Scalar* data() const;
-    /** \sa MapBase::stride() */
-    inline int stride() const;
+    inline int innerStride() const;
+    inline int outerStride() const;
     #endif
 
   protected:
@@ -260,17 +274,24 @@ class Block<MatrixType,BlockRows,BlockCols,HasDirectAccess>
              && startCol >= 0 && blockCols >= 0 && startCol + blockCols <= matrix.cols());
     }
 
-    /** \sa MapBase::stride() */
-    inline int stride() const
+    /** \sa MapBase::innerStride() */
+    inline int innerStride() const
+    {
+      return (RowsAtCompileTime==1 && !(int(MatrixType::Flags)&RowMajorBit))
+          || (ColsAtCompileTime==1 && (int(MatrixType::Flags)&RowMajorBit))
+          ? m_matrix.outerStride()
+          : m_matrix.innerStride();
+    }
+    
+    /** \sa MapBase::outerStride() */
+    inline int outerStride() const
     {
-      return    ((!Base::IsVectorAtCompileTime)
-              || (BlockRows==1 && ((Flags&RowMajorBit)==0))
-              || (BlockCols==1 && ((Flags&RowMajorBit)==RowMajorBit)))
-              ? m_matrix.stride() : 1;
+      return IsVectorAtCompileTime ? 0 : m_matrix.outerStride();
     }
 
   #ifndef __SUNPRO_CC
   // FIXME sunstudio is not friendly with the above friend...
+  // META-FIXME there is no 'friend' keyword around here. Is this obsolete?
   protected:
   #endif
 
diff --git a/Eigen/src/Core/DenseBase.h b/Eigen/src/Core/DenseBase.h
index 21d792f49..d8f789ae0 100644
--- a/Eigen/src/Core/DenseBase.h
+++ b/Eigen/src/Core/DenseBase.h
@@ -158,31 +158,60 @@ template<typename Derived> class DenseBase
       * In other words, this function returns
       * \code rows()==1 || cols()==1 \endcode
       * \sa rows(), cols(), IsVectorAtCompileTime. */
-    inline bool isVector() const { return rows()==1 || cols()==1; }
-    /** \returns the size of the storage major dimension,
-      * i.e., the number of columns for a columns major matrix, and the number of rows otherwise */
-    int outerSize() const { return (int(Flags)&RowMajorBit) ? this->rows() : this->cols(); }
-    /** \returns the size of the inner dimension according to the storage order,
-      * i.e., the number of rows for a columns major matrix, and the number of cols otherwise */
-    int innerSize() const { return (int(Flags)&RowMajorBit) ? this->cols() : this->rows(); }
-
-    /** Only plain matrices, not expressions may be resized; therefore the only useful resize method is
-      * Matrix::resize(). The present method only asserts that the new size equals the old size, and does
+
+    /** \returns the outer size.
+      *
+      * \note For a vector, this returns just 1. For a matrix (non-vector), this is the major dimension
+      * with respect to the storage order, i.e., the number of columns for a column-major matrix,
+      * and the number of rows for a row-major matrix. */
+    int outerSize() const
+    {
+      return IsVectorAtCompileTime ? 1
+           : (int(Flags)&RowMajorBit) ? this->rows() : this->cols();
+    }
+
+    /** \returns the inner size.
+      *
+      * \note For a vector, this is just the size. For a matrix (non-vector), this is the minor dimension
+      * with respect to the storage order, i.e., the number of rows for a column-major matrix,
+      * and the number of columns for a row-major matrix. */
+    int innerSize() const
+    {
+      return IsVectorAtCompileTime ? this->size()
+           : (int(Flags)&RowMajorBit) ? this->cols() : this->rows();
+    }
+
+    /** Only plain matrices/arrays, not expressions, may be resized; therefore the only useful resize methods are
+      * Matrix::resize() and Array::resize(). The present method only asserts that the new size equals the old size, and does
       * nothing else.
       */
     void resize(int size)
     {
       ei_assert(size == this->size()
-                && "MatrixBase::resize() does not actually allow to resize.");
+                && "DenseBase::resize() does not actually allow to resize.");
     }
-    /** Only plain matrices, not expressions may be resized; therefore the only useful resize method is
-      * Matrix::resize(). The present method only asserts that the new size equals the old size, and does
+    /** Only plain matrices/arrays, not expressions, may be resized; therefore the only useful resize methods are
+      * Matrix::resize() and Array::resize(). The present method only asserts that the new size equals the old size, and does
       * nothing else.
       */
     void resize(int rows, int cols)
     {
       ei_assert(rows == this->rows() && cols == this->cols()
-                && "MatrixBase::resize() does not actually allow to resize.");
+                && "DenseBase::resize() does not actually allow to resize.");
+    }
+
+    int innerStride() const
+    {
+      EIGEN_STATIC_ASSERT(int(Flags)&DirectAccessBit,
+                          THIS_METHOD_IS_ONLY_FOR_EXPRESSIONS_WITH_DIRECT_MEMORY_ACCESS_SUCH_AS_MAP_OR_PLAIN_MATRICES)
+      return derived().innerStride();
+    }
+
+    int outerStride() const
+    {
+      EIGEN_STATIC_ASSERT(int(Flags)&DirectAccessBit,
+                          THIS_METHOD_IS_ONLY_FOR_EXPRESSIONS_WITH_DIRECT_MEMORY_ACCESS_SUCH_AS_MAP_OR_PLAIN_MATRICES)
+      return derived().outerStride();
     }
 
 #ifndef EIGEN_PARSED_BY_DOXYGEN
@@ -407,13 +436,6 @@ template<typename Derived> class DenseBase
     template<typename OtherDerived>
     void swap(DenseBase<OtherDerived> EIGEN_REF_TO_TEMPORARY other);
 
-    /** \returns number of elements to skip to pass from one row (resp. column) to another
-      * for a row-major (resp. column-major) matrix.
-      * Combined with coeffRef() and the \ref flags flags, it allows a direct access to the data
-      * of the underlying matrix.
-      */
-    inline int stride() const { return derived().stride(); }
-
     inline const NestByValue<Derived> nestByValue() const;
     inline const ForceAlignedAccess<Derived> forceAlignedAccess() const;
     inline ForceAlignedAccess<Derived> forceAlignedAccess();
diff --git a/Eigen/src/Core/DenseStorageBase.h b/Eigen/src/Core/DenseStorageBase.h
index 5c8e48768..04dfb1176 100644
--- a/Eigen/src/Core/DenseStorageBase.h
+++ b/Eigen/src/Core/DenseStorageBase.h
@@ -253,13 +253,13 @@ class DenseStorageBase : public _Base<Derived>
     {
       if(RowsAtCompileTime == 1)
       {
-        ei_assert(other.isVector());
-        resize(1, other.size());
+        ei_assert(other.rows() == 1);
+        resize(1, other.cols());
       }
       else if(ColsAtCompileTime == 1)
       {
-        ei_assert(other.isVector());
-        resize(other.size(), 1);
+        ei_assert(other.cols() == 1);
+        resize(other.rows(), 1);
       }
       else resize(other.rows(), other.cols());
     }
diff --git a/Eigen/src/Core/Map.h b/Eigen/src/Core/Map.h
index 83688dbca..432bf1661 100644
--- a/Eigen/src/Core/Map.h
+++ b/Eigen/src/Core/Map.h
@@ -1,7 +1,7 @@
 // This file is part of Eigen, a lightweight C++ template library
 // for linear algebra.
 //
-// Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com>
+// Copyright (C) 2007-2010 Benoit Jacob <jacob.benoit.1@gmail.com>
 // Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr>
 //
 // Eigen is free software; you can redistribute it and/or
@@ -48,32 +48,59 @@
   *
   * \sa Matrix::Map()
   */
-template<typename MatrixType, int Options>
-struct ei_traits<Map<MatrixType, Options> > : public ei_traits<MatrixType>
+template<typename MatrixType, int Options, typename StrideType>
+struct ei_traits<Map<MatrixType, Options, StrideType> >
+  : public ei_traits<MatrixType>
 {
   enum {
-    Flags = (Options&Aligned)==Aligned ? ei_traits<MatrixType>::Flags |  AlignedBit
-                                       : ei_traits<MatrixType>::Flags & ~AlignedBit
-  };
+    Flags0 = ei_traits<MatrixType>::Flags,
+    Flags1 = ((Options&Aligned)==Aligned ? Flags0 |  AlignedBit
+                                         : Flags0 & ~AlignedBit),
+    Flags = int(StrideType::InnerStrideAtCompileTime)==1 ? Flags1 : (Flags1 & ~PacketAccessBit),
+    InnerStrideAtCompileTime = int(StrideType::InnerStrideAtCompileTime) != 0 ? int(StrideType::InnerStrideAtCompileTime) : 1,
+    OuterStrideAtCompileTime =
+        int(StrideType::OuterStrideAtCompileTime != 0) ? int(StrideType::OuterStrideAtCompileTime)
+          : int(MatrixType::IsVectorAtCompileTime) ? int(MatrixType::SizeAtCompileTime)
+          : int(Flags)&RowMajorBit ? int(MatrixType::ColsAtCompileTime)
+          : int(MatrixType::RowsAtCompileTime)
+    };
 };
 
-template<typename MatrixType, int Options> class Map
-  : public MapBase<Map<MatrixType, Options>,
-                   typename MatrixType::template MakeBase< Map<MatrixType, Options> >::Type>
+template<typename MatrixType, int Options, typename StrideType> class Map
+  : public MapBase<Map<MatrixType, Options, StrideType>,
+                   typename MatrixType::template MakeBase<
+                     Map<MatrixType, Options, StrideType>
+                   >::Type>
 {
   public:
 
     typedef MapBase<Map,typename MatrixType::template MakeBase<Map>::Type> Base;
+
     EIGEN_DENSE_PUBLIC_INTERFACE(Map)
 
-    inline int stride() const { return this->innerSize(); }
+    inline int innerStride() const
+    {
+      return StrideType::InnerStrideAtCompileTime != 0 ? m_stride.inner() : 1;
+    }
 
-    inline Map(const Scalar* data) : Base(data) {}
+    inline int outerStride() const
+    {
+      return StrideType::OuterStrideAtCompileTime != 0 ? m_stride.outer()
+           : IsVectorAtCompileTime ? this->size()
+           : int(Flags)&RowMajorBit ? this->cols()
+           : this->rows();
+    }
+
+    inline Map(const Scalar* data, const StrideType& stride = StrideType())
+      : Base(data), m_stride(stride) {}
 
-    inline Map(const Scalar* data, int size) : Base(data, size) {}
+    inline Map(const Scalar* data, int size, const StrideType& stride = StrideType())
+      : Base(data, size), m_stride(stride) {}
 
-    inline Map(const Scalar* data, int rows, int cols) : Base(data, rows, cols) {}
+    inline Map(const Scalar* data, int rows, int cols, const StrideType& stride = StrideType())
+      : Base(data, rows, cols), m_stride(stride) {}
 
+/*
     inline void resize(int rows, int cols)
     {
       EIGEN_ONLY_USED_FOR_DEBUG(rows);
@@ -88,8 +115,12 @@ template<typename MatrixType, int Options> class Map
       EIGEN_ONLY_USED_FOR_DEBUG(size);
       ei_assert(size == this->size());
     }
+*/
 
     EIGEN_INHERIT_ASSIGNMENT_OPERATORS(Map)
+
+  protected:
+    StrideType m_stride;
 };
 
 template<typename _Scalar, int _Rows, int _Cols, int _StorageOrder, int _MaxRows, int _MaxCols>
diff --git a/Eigen/src/Core/MapBase.h b/Eigen/src/Core/MapBase.h
index a922d8bb0..6bac2ed4c 100644
--- a/Eigen/src/Core/MapBase.h
+++ b/Eigen/src/Core/MapBase.h
@@ -1,7 +1,7 @@
 // This file is part of Eigen, a lightweight C++ template library
 // for linear algebra.
 //
-// Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com>
+// Copyright (C) 2007-2010 Benoit Jacob <jacob.benoit.1@gmail.com>
 // Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr>
 //
 // Eigen is free software; you can redistribute it and/or
@@ -37,12 +37,12 @@ template<typename Derived, typename Base> class MapBase
 {
   public:
 
-//     typedef MatrixBase<Derived> Base;
     enum {
       IsRowMajor = (int(ei_traits<Derived>::Flags) & RowMajorBit) ? 1 : 0,
       RowsAtCompileTime = ei_traits<Derived>::RowsAtCompileTime,
       ColsAtCompileTime = ei_traits<Derived>::ColsAtCompileTime,
-      SizeAtCompileTime = Base::SizeAtCompileTime
+      SizeAtCompileTime = Base::SizeAtCompileTime,
+      InnerStrideAtCompileTime = ei_traits<Derived>::InnerStrideAtCompileTime
     };
 
     typedef typename ei_traits<Derived>::Scalar Scalar;
@@ -52,90 +52,104 @@ template<typename Derived, typename Base> class MapBase
     inline int rows() const { return m_rows.value(); }
     inline int cols() const { return m_cols.value(); }
 
-    /** Returns the leading dimension (for matrices) or the increment (for vectors) to be used with data().
+    /** \returns the pointer increment between two consecutive elements.
       *
-      * More precisely:
-      *  - for a column major matrix it returns the number of elements between two successive columns
-      *  - for a row major matrix it returns the number of elements between two successive rows
-      *  - for a vector it returns the number of elements between two successive coefficients
-      * This function has to be used together with the MapBase::data() function.
+      * \note For vectors, the storage order is ignored. For matrices (non-vectors), we're looking
+      *       at the increment between two consecutive elements within a slice in the inner direction.
       *
-      * \sa MapBase::data() */
-    inline int stride() const { return derived().stride(); }
+      * \sa outerStride(), data(), rowStride(), colStride()
+      */
+    inline int innerStride() const { return derived().innerStride(); }
+
+    /** \returns the pointer increment between two consecutive inner slices (for example, between two consecutive columns
+      *          in a column-major matrix).
+      *
+      * \note For vectors, the storage order is ignored, there is only one inner slice, and so this method returns 1.
+      *       For matrices (non-vectors), the notion of inner slice depends on the storage order.
+      *
+      * \sa innerStride(), data(), rowStride(), colStride()
+      */
+    inline int outerStride() const { return derived().outerStride(); }
+
+    /** \returns the pointer increment between two consecutive rows.
+      *
+      * \sa data(), innerStride(), outerStride(), colStride()
+      */
+    inline int rowStride() const
+    {
+      return (RowsAtCompileTime==1 || IsRowMajor) ? outerStride() : innerStride();
+    }
+
+    /** \returns the pointer increment between two consecutive columns.
+      *
+      * \sa data(), innerStride(), outerStride(), rowStride()
+      */
+    inline int colStride() const
+    {
+      return (RowsAtCompileTime==1 || IsRowMajor) ? innerStride() : outerStride();
+    }
 
     /** Returns a pointer to the first coefficient of the matrix or vector.
-      * This function has to be used together with the stride() function.
       *
-      * \sa MapBase::stride() */
+      * \note When addressing this data, make sure to honor the strides returned by innerStride() and outerStride().
+      *
+      * \sa innerStride(), outerStride()
+      */
     inline const Scalar* data() const { return m_data; }
 
     inline const Scalar& coeff(int row, int col) const
     {
-      if(IsRowMajor)
-        return m_data[col + row * stride()];
-      else // column-major
-        return m_data[row + col * stride()];
+      return m_data[col * colStride() + row * rowStride()];
     }
 
     inline Scalar& coeffRef(int row, int col)
     {
-      if(IsRowMajor)
-        return const_cast<Scalar*>(m_data)[col + row * stride()];
-      else // column-major
-        return const_cast<Scalar*>(m_data)[row + col * stride()];
+      return const_cast<Scalar*>(m_data)[col * colStride() + row * rowStride()];
     }
 
     inline const Scalar& coeff(int index) const
     {
       ei_assert(Derived::IsVectorAtCompileTime || (ei_traits<Derived>::Flags & LinearAccessBit));
-      if ( ((RowsAtCompileTime == 1) == IsRowMajor) || !int(Derived::IsVectorAtCompileTime) )
-        return m_data[index];
-      else
-        return m_data[index*stride()];
+      return m_data[index * innerStride()];
     }
 
     inline Scalar& coeffRef(int index)
     {
       ei_assert(Derived::IsVectorAtCompileTime || (ei_traits<Derived>::Flags & LinearAccessBit));
-      if ( ((RowsAtCompileTime == 1) == IsRowMajor) || !int(Derived::IsVectorAtCompileTime) )
-        return const_cast<Scalar*>(m_data)[index];
-      else
-        return const_cast<Scalar*>(m_data)[index*stride()];
+      return const_cast<Scalar*>(m_data)[index * innerStride()];
     }
 
     template<int LoadMode>
     inline PacketScalar packet(int row, int col) const
     {
       return ei_ploadt<Scalar, LoadMode>
-               (m_data + (IsRowMajor ? col + row * stride()
-                                     : row + col * stride()));
+               (m_data + (col * colStride() + row * rowStride()));
     }
 
     template<int LoadMode>
     inline PacketScalar packet(int index) const
     {
-      return ei_ploadt<Scalar, LoadMode>(m_data + index);
+      return ei_ploadt<Scalar, LoadMode>(m_data + index * innerStride());
     }
 
     template<int StoreMode>
     inline void writePacket(int row, int col, const PacketScalar& x)
     {
       ei_pstoret<Scalar, PacketScalar, StoreMode>
-               (const_cast<Scalar*>(m_data) + (IsRowMajor ? col + row * stride()
-                                                          : row + col * stride()), x);
+               (const_cast<Scalar*>(m_data) + (col * colStride() + row * rowStride()), x);
     }
 
     template<int StoreMode>
     inline void writePacket(int index, const PacketScalar& x)
     {
       ei_pstoret<Scalar, PacketScalar, StoreMode>
-        (const_cast<Scalar*>(m_data) + index, x);
+        (const_cast<Scalar*>(m_data) + index * innerStride(), x);
     }
 
     inline MapBase(const Scalar* data) : m_data(data), m_rows(RowsAtCompileTime), m_cols(ColsAtCompileTime)
     {
       EIGEN_STATIC_ASSERT_FIXED_SIZE(Derived)
-      checkDataAlignment();
+      checkSanity();
     }
 
     inline MapBase(const Scalar* data, int size)
@@ -146,7 +160,7 @@ template<typename Derived, typename Base> class MapBase
       EIGEN_STATIC_ASSERT_VECTOR_ONLY(Derived)
       ei_assert(size >= 0);
       ei_assert(data == 0 || SizeAtCompileTime == Dynamic || SizeAtCompileTime == size);
-      checkDataAlignment();
+      checkSanity();
     }
 
     inline MapBase(const Scalar* data, int rows, int cols)
@@ -155,7 +169,7 @@ template<typename Derived, typename Base> class MapBase
       ei_assert( (data == 0)
               || (   rows >= 0 && (RowsAtCompileTime == Dynamic || RowsAtCompileTime == rows)
                   && cols >= 0 && (ColsAtCompileTime == Dynamic || ColsAtCompileTime == cols)));
-      checkDataAlignment();
+      checkSanity();
     }
 
     Derived& operator=(const MapBase& other)
@@ -167,10 +181,12 @@ template<typename Derived, typename Base> class MapBase
 
   protected:
 
-    void checkDataAlignment() const
+    void checkSanity() const
     {
       ei_assert( ((!(ei_traits<Derived>::Flags&AlignedBit))
                   || ((size_t(m_data)&0xf)==0)) && "data is not aligned");
+      ei_assert( ((!(ei_traits<Derived>::Flags&PacketAccessBit))
+                  || (innerStride()==1)) && "packet access incompatible with inner stride greater than 1");
     }
 
     const Scalar* EIGEN_RESTRICT m_data;
diff --git a/Eigen/src/Core/Matrix.h b/Eigen/src/Core/Matrix.h
index 6f194ffba..e011ae8b9 100644
--- a/Eigen/src/Core/Matrix.h
+++ b/Eigen/src/Core/Matrix.h
@@ -120,7 +120,10 @@ struct ei_traits<Matrix<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols> >
     MaxRowsAtCompileTime = _MaxRows,
     MaxColsAtCompileTime = _MaxCols,
     Flags = ei_compute_matrix_flags<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols>::ret,
-    CoeffReadCost = NumTraits<Scalar>::ReadCost
+    CoeffReadCost = NumTraits<Scalar>::ReadCost,
+    InnerStrideAtCompileTime = 1,
+    OuterStrideAtCompileTime = (RowsAtCompileTime==1||ColsAtCompileTime==1) ? 1
+     : (int(Flags)&RowMajorBit) ? RowsAtCompileTime : ColsAtCompileTime
   };
 };
 
@@ -318,6 +321,9 @@ class Matrix
     void swap(MatrixBase<OtherDerived> EIGEN_REF_TO_TEMPORARY other)
     { this->_swap(other.derived()); }
 
+    inline int innerStride() const { return 1; }
+    inline int outerStride() const { return this->innerSize(); }
+
     /////////// Geometry module ///////////
 
     template<typename OtherDerived>
diff --git a/Eigen/src/Core/Product.h b/Eigen/src/Core/Product.h
index af05773ee..53277169c 100644
--- a/Eigen/src/Core/Product.h
+++ b/Eigen/src/Core/Product.h
@@ -336,7 +336,7 @@ template<> struct ei_gemv_selector<OnTheRight,ColMajor,true>
     ei_cache_friendly_product_colmajor_times_vector
       <LhsBlasTraits::NeedToConjugate,RhsBlasTraits::NeedToConjugate>(
       dest.size(),
-      &actualLhs.const_cast_derived().coeffRef(0,0), actualLhs.stride(),
+      &actualLhs.const_cast_derived().coeffRef(0,0), ei_outer_stride_or_outer_size(actualLhs),
       actualRhs, actualDest, actualAlpha);
 
     if (!EvalToDest)
@@ -381,7 +381,7 @@ template<> struct ei_gemv_selector<OnTheRight,RowMajor,true>
 
     ei_cache_friendly_product_rowmajor_times_vector
       <LhsBlasTraits::NeedToConjugate,RhsBlasTraits::NeedToConjugate>(
-        &actualLhs.const_cast_derived().coeffRef(0,0), actualLhs.stride(),
+        &actualLhs.const_cast_derived().coeffRef(0,0), ei_outer_stride_or_outer_size(actualLhs),
         rhs_data, prod.rhs().size(), dest, actualAlpha);
 
     if (!DirectlyUseRhs) ei_aligned_stack_delete(Scalar, rhs_data, prod.rhs().size());
diff --git a/Eigen/src/Core/ReturnByValue.h b/Eigen/src/Core/ReturnByValue.h
index 920269365..8d45fc31b 100644
--- a/Eigen/src/Core/ReturnByValue.h
+++ b/Eigen/src/Core/ReturnByValue.h
@@ -34,14 +34,9 @@ struct ei_traits<ReturnByValue<Derived> >
   : public ei_traits<typename ei_traits<Derived>::ReturnMatrixType>
 {
   enum {
-    // FIXME had to remove the DirectAccessBit for usage like
-    //   matrix.inverse().block(...)
-    // because the Block ctor with direct access
-    // wants to call coeffRef() to get an address, and that fails (infinite recursion) as ReturnByValue
-    // doesnt implement coeffRef().
-    // The fact that I had to do that shows that when doing xpr.block() with a non-direct-access xpr,
-    // even if xpr has the EvalBeforeNestingBit, the block() doesn't use direct access on the evaluated
-    // xpr.
+    // We're disabling the DirectAccess because e.g. the constructor of
+    // the Block-with-DirectAccess expression requires to have a coeffRef method.
+    // Also, we don't want to have to implement the stride stuff.
     Flags = (ei_traits<typename ei_traits<Derived>::ReturnMatrixType>::Flags
              | EvalBeforeNestingBit) & ~DirectAccessBit
   };
diff --git a/Eigen/src/Core/Transpose.h b/Eigen/src/Core/Transpose.h
index bd06d8464..753a67ee0 100644
--- a/Eigen/src/Core/Transpose.h
+++ b/Eigen/src/Core/Transpose.h
@@ -80,6 +80,9 @@ template<typename MatrixType> class Transpose
     typename ei_cleantype<typename MatrixType::Nested>::type&
     nestedExpression() { return m_matrix.const_cast_derived(); }
 
+    enum { InnerStrideAtCompileTime = ei_inner_stride_at_compile_time<MatrixType>::ret,
+           OuterStrideAtCompileTime = ei_outer_stride_at_compile_time<MatrixType>::ret };
+
   protected:
     const typename MatrixType::Nested m_matrix;
 };
@@ -93,7 +96,8 @@ template<typename MatrixType> class TransposeImpl<MatrixType,Dense>
     typedef typename MatrixType::template MakeBase<Transpose<MatrixType> >::Type Base;
     EIGEN_DENSE_PUBLIC_INTERFACE(Transpose<MatrixType>)
 
-    inline int stride() const { return derived().nestedExpression().stride(); }
+    inline int innerStride() const { return derived().nestedExpression().innerStride(); }
+    inline int outerStride() const { return derived().nestedExpression().outerStride(); }
     inline Scalar* data() { return derived().nestedExpression().data(); }
     inline const Scalar* data() const { return derived().nestedExpression().data(); }
 
diff --git a/Eigen/src/Core/products/GeneralMatrixMatrix.h b/Eigen/src/Core/products/GeneralMatrixMatrix.h
index beec17ee4..03c77cc78 100644
--- a/Eigen/src/Core/products/GeneralMatrixMatrix.h
+++ b/Eigen/src/Core/products/GeneralMatrixMatrix.h
@@ -147,6 +147,7 @@ class GeneralProduct<Lhs, Rhs, GemmProduct>
 
       const ActualLhsType lhs = LhsBlasTraits::extract(m_lhs);
       const ActualRhsType rhs = RhsBlasTraits::extract(m_rhs);
+      ei_assert(ei_inner_stride_at_compile_time<ActualLhsType>::ret == 1);
 
       Scalar actualAlpha = alpha * LhsBlasTraits::extractScalarFactor(m_lhs)
                                  * RhsBlasTraits::extractScalarFactor(m_rhs);
@@ -158,9 +159,9 @@ class GeneralProduct<Lhs, Rhs, GemmProduct>
         (Dest::Flags&RowMajorBit) ? RowMajor : ColMajor>
       ::run(
           this->rows(), this->cols(), lhs.cols(),
-          (const Scalar*)&(lhs.const_cast_derived().coeffRef(0,0)), lhs.stride(),
-          (const Scalar*)&(rhs.const_cast_derived().coeffRef(0,0)), rhs.stride(),
-          (Scalar*)&(dst.coeffRef(0,0)), dst.stride(),
+          (const Scalar*)&(lhs.const_cast_derived().coeffRef(0,0)), ei_outer_stride_or_outer_size(lhs),
+          (const Scalar*)&(rhs.const_cast_derived().coeffRef(0,0)), ei_outer_stride_or_outer_size(rhs),
+          (Scalar*)&(dst.coeffRef(0,0)), ei_outer_stride_or_outer_size(dst),
           actualAlpha);
     }
 };
diff --git a/Eigen/src/Core/util/ForwardDeclarations.h b/Eigen/src/Core/util/ForwardDeclarations.h
index aed0abe6d..c2d45dc30 100644
--- a/Eigen/src/Core/util/ForwardDeclarations.h
+++ b/Eigen/src/Core/util/ForwardDeclarations.h
@@ -1,7 +1,8 @@
 // This file is part of Eigen, a lightweight C++ template library
 // for linear algebra.
 //
-// Copyright (C) 2007-2009 Benoit Jacob <jacob.benoit.1@gmail.com>
+// Copyright (C) 2007-2010 Benoit Jacob <jacob.benoit.1@gmail.com>
+// Copyright (C) 2008-2009 Gael Guennebaud <g.gael@free.fr>
 //
 // Eigen is free software; you can redistribute it and/or
 // modify it under the terms of the GNU Lesser General Public
@@ -60,7 +61,9 @@ template<typename _Scalar, int SizeAtCompileTime, int MaxSizeAtCompileTime=SizeA
 template<typename MatrixType, typename DiagonalType, int ProductOrder> class DiagonalProduct;
 template<typename MatrixType, int Index> class Diagonal;
 
-template<typename MatrixType, int Options=Unaligned> class Map;
+template<int InnerStrideAtCompileTime = Dynamic, int OuterStrideAtCompileTime = Dynamic> class Stride;
+template<typename MatrixType, int Options=Unaligned, typename StrideType = Stride<0,0> > class Map;
+
 template<typename Derived> class TriangularBase;
 template<typename MatrixType, unsigned int Mode> class TriangularView;
 template<typename MatrixType, unsigned int Mode> class SelfAdjointView;
diff --git a/Eigen/src/Core/util/StaticAssert.h b/Eigen/src/Core/util/StaticAssert.h
index 619e7664d..5252b28c5 100644
--- a/Eigen/src/Core/util/StaticAssert.h
+++ b/Eigen/src/Core/util/StaticAssert.h
@@ -2,7 +2,7 @@
 // for linear algebra.
 //
 // Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr>
-// Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com>
+// 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
@@ -46,7 +46,7 @@
     // if native static_assert is enabled, let's use it
     #define EIGEN_STATIC_ASSERT(X,MSG) static_assert(X,#MSG);
 
-  #else // CXX0X
+  #else // not CXX0X
 
     template<bool condition>
     struct ei_static_assert {};
@@ -81,7 +81,8 @@
         BOTH_MATRICES_MUST_HAVE_THE_SAME_STORAGE_ORDER,
         THIS_METHOD_IS_ONLY_FOR_DIAGONAL_MATRIX,
         THE_MATRIX_OR_EXPRESSION_THAT_YOU_PASSED_DOES_NOT_HAVE_THE_EXPECTED_TYPE,
-        THIS_METHOD_IS_ONLY_FOR_EXPRESSIONS_WITH_DIRECT_MEMORY_ACCESS_SUCH_AS_MAP_OR_PLAIN_MATRICES
+        THIS_METHOD_IS_ONLY_FOR_EXPRESSIONS_WITH_DIRECT_MEMORY_ACCESS_SUCH_AS_MAP_OR_PLAIN_MATRICES,
+        YOU_ALREADY_SPECIFIED_THIS_STRIDE
       };
     };
 
diff --git a/Eigen/src/Core/util/XprHelper.h b/Eigen/src/Core/util/XprHelper.h
index a86e7be89..8ddf4450a 100644
--- a/Eigen/src/Core/util/XprHelper.h
+++ b/Eigen/src/Core/util/XprHelper.h
@@ -50,7 +50,7 @@ template<int Value> class ei_int_if_dynamic
 {
   public:
     EIGEN_EMPTY_STRUCT_CTOR(ei_int_if_dynamic)
-    explicit ei_int_if_dynamic(int) {}
+    explicit ei_int_if_dynamic(int v) { EIGEN_ONLY_USED_FOR_DEBUG(v); ei_assert(v == Value); }
     static int value() { return Value; }
     void setValue(int) {}
 };
@@ -58,7 +58,7 @@ template<int Value> class ei_int_if_dynamic
 template<> class ei_int_if_dynamic<Dynamic>
 {
     int m_value;
-    ei_int_if_dynamic() {}
+    ei_int_if_dynamic() { ei_assert(false); }
   public:
     explicit ei_int_if_dynamic(int value) : m_value(value) {}
     int value() const { return m_value; }