From 6f0992c05b92163ed5fb0cedf03faed43805519f Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Fri, 19 Feb 2016 22:21:02 +0100
Subject: [PATCH] Fix nesting type and complete reflection methods of Block
 expressions.

---
 Eigen/src/Core/Block.h             | 30 ++++++++++++++++++++++++++----
 Eigen/src/SparseCore/SparseBlock.h | 15 +++++++++------
 2 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/Eigen/src/Core/Block.h b/Eigen/src/Core/Block.h
index cf962aed1..661e64f3d 100644
--- a/Eigen/src/Core/Block.h
+++ b/Eigen/src/Core/Block.h
@@ -173,6 +173,7 @@ template<typename XprType, int BlockRows, int BlockCols, bool InnerPanel, bool H
   : public internal::dense_xpr_base<Block<XprType, BlockRows, BlockCols, InnerPanel> >::type
 {
     typedef Block<XprType, BlockRows, BlockCols, InnerPanel> BlockType;
+    typedef typename internal::ref_selector<XprType>::non_const_type XprTypeNested;
   public:
 
     typedef typename internal::dense_xpr_base<BlockType>::type Base;
@@ -294,10 +295,13 @@ template<typename XprType, int BlockRows, int BlockCols, bool InnerPanel, bool H
     #endif
 
     EIGEN_DEVICE_FUNC
-    const typename internal::remove_all<typename XprType::Nested>::type& nestedExpression() const
+    const typename internal::remove_all<XprTypeNested>::type& nestedExpression() const
     { 
       return m_xpr; 
     }
+
+    EIGEN_DEVICE_FUNC
+    XprType& nestedExpression() { return m_xpr; }
       
     EIGEN_DEVICE_FUNC
     StorageIndex startRow() const
@@ -313,7 +317,7 @@ template<typename XprType, int BlockRows, int BlockCols, bool InnerPanel, bool H
 
   protected:
 
-    typename XprType::Nested m_xpr;
+    XprTypeNested m_xpr;
     const internal::variable_if_dynamic<StorageIndex, XprType::RowsAtCompileTime == 1 ? 0 : Dynamic> m_startRow;
     const internal::variable_if_dynamic<StorageIndex, XprType::ColsAtCompileTime == 1 ? 0 : Dynamic> m_startCol;
     const internal::variable_if_dynamic<StorageIndex, RowsAtCompileTime> m_blockRows;
@@ -326,6 +330,7 @@ class BlockImpl_dense<XprType,BlockRows,BlockCols, InnerPanel,true>
   : public MapBase<Block<XprType, BlockRows, BlockCols, InnerPanel> >
 {
     typedef Block<XprType, BlockRows, BlockCols, InnerPanel> BlockType;
+    typedef typename internal::ref_selector<XprType>::non_const_type XprTypeNested;
     enum {
       XprTypeIsRowMajor = (int(traits<XprType>::Flags)&RowMajorBit) != 0
     };
@@ -371,10 +376,13 @@ class BlockImpl_dense<XprType,BlockRows,BlockCols, InnerPanel,true>
     }
 
     EIGEN_DEVICE_FUNC
-    const typename internal::remove_all<typename XprType::Nested>::type& nestedExpression() const
+    const typename internal::remove_all<XprTypeNested>::type& nestedExpression() const
     { 
       return m_xpr; 
     }
+
+    EIGEN_DEVICE_FUNC
+    XprType& nestedExpression() { return m_xpr; }
       
     /** \sa MapBase::innerStride() */
     EIGEN_DEVICE_FUNC
@@ -392,6 +400,20 @@ class BlockImpl_dense<XprType,BlockRows,BlockCols, InnerPanel,true>
       return m_outerStride;
     }
 
+    EIGEN_DEVICE_FUNC
+    StorageIndex startRow() const
+    {
+      std::ptrdiff_t diff = Base::data() - m_xpr.data();
+      return XprType::IsRowMajor ? (diff/m_xpr.outerStride()) : (diff%m_xpr.outerStride());
+    }
+
+    EIGEN_DEVICE_FUNC
+    StorageIndex startCol() const
+    {
+      std::ptrdiff_t diff = Base::data() - m_xpr.data();
+      return XprType::IsRowMajor ? (diff%m_xpr.outerStride()) : (diff/m_xpr.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?
@@ -417,7 +439,7 @@ class BlockImpl_dense<XprType,BlockRows,BlockCols, InnerPanel,true>
                     : m_xpr.innerStride();
     }
 
-    typename XprType::Nested m_xpr;
+    XprTypeNested m_xpr;
     Index m_outerStride;
 };
 
diff --git a/Eigen/src/SparseCore/SparseBlock.h b/Eigen/src/SparseCore/SparseBlock.h
index 3a811113f..00409fb37 100644
--- a/Eigen/src/SparseCore/SparseBlock.h
+++ b/Eigen/src/SparseCore/SparseBlock.h
@@ -28,11 +28,11 @@ protected:
 public:
     EIGEN_SPARSE_PUBLIC_INTERFACE(BlockType)
 
-    inline BlockImpl(const XprType& xpr, Index i)
+    inline BlockImpl(XprType& xpr, Index i)
       : m_matrix(xpr), m_outerStart(convert_index(i)), m_outerSize(OuterSize)
     {}
 
-    inline BlockImpl(const XprType& xpr, Index startRow, Index startCol, Index blockRows, Index blockCols)
+    inline BlockImpl(XprType& xpr, Index startRow, Index startCol, Index blockRows, Index blockCols)
       : m_matrix(xpr), m_outerStart(convert_index(IsRowMajor ? startRow : startCol)), m_outerSize(convert_index(IsRowMajor ? blockRows : blockCols))
     {}
 
@@ -61,7 +61,8 @@ public:
       return m_matrix.coeff(IsRowMajor ? m_outerStart : index, IsRowMajor ? index :  m_outerStart);
     }
     
-    inline const _MatrixTypeNested& nestedExpression() const { return m_matrix; }
+    inline const XprType& nestedExpression() const { return m_matrix; }
+    inline XprType& nestedExpression() { return m_matrix; }
     Index startRow() const { return IsRowMajor ? m_outerStart : 0; }
     Index startCol() const { return IsRowMajor ? 0 : m_outerStart; }
     Index blockRows() const { return IsRowMajor ? m_outerSize.value() : m_matrix.rows(); }
@@ -69,7 +70,7 @@ public:
 
   protected:
 
-    typename XprType::Nested m_matrix;
+    typename internal::ref_selector<XprType>::non_const_type m_matrix;
     Index m_outerStart;
     const internal::variable_if_dynamic<Index, OuterSize> m_outerSize;
   
@@ -263,7 +264,8 @@ public:
     EIGEN_STRONG_INLINE Index rows() const { return IsRowMajor ? m_outerSize.value() : m_matrix.rows(); }
     EIGEN_STRONG_INLINE Index cols() const { return IsRowMajor ? m_matrix.cols() : m_outerSize.value(); }
     
-    inline const _MatrixTypeNested& nestedExpression() const { return m_matrix; }
+    inline const SparseMatrixType& nestedExpression() const { return m_matrix; }
+    inline SparseMatrixType& nestedExpression() { return m_matrix; }
     Index startRow() const { return IsRowMajor ? m_outerStart : 0; }
     Index startCol() const { return IsRowMajor ? 0 : m_outerStart; }
     Index blockRows() const { return IsRowMajor ? m_outerSize.value() : m_matrix.rows(); }
@@ -419,7 +421,8 @@ public:
                             m_startCol.value() + (RowsAtCompileTime == 1 ? index : 0));
     }
     
-    inline const _MatrixTypeNested& nestedExpression() const { return m_matrix; }
+    inline const XprType& nestedExpression() const { return m_matrix; }
+    inline XprType& nestedExpression() { return m_matrix; }
     Index startRow() const { return m_startRow.value(); }
     Index startCol() const { return m_startCol.value(); }
     Index blockRows() const { return m_blockRows.value(); }