trsv: add support for inner-stride!=1, reduce code instanciation, move implementation to a new products/XX.h file

3 files changed, 169 insertions, 94 deletions

diff --git a/Eigen/Core b/Eigen/Core
index 4401a4e14..5e81d10d1 100644
--- a/Eigen/Core
+++ b/Eigen/Core
@@ -315,6 +315,7 @@ using std::size_t;
 #include "src/Core/products/TriangularMatrixVector.h"
 #include "src/Core/products/TriangularMatrixMatrix.h"
 #include "src/Core/products/TriangularSolverMatrix.h"
+#include "src/Core/products/TriangularSolverVector.h"
 #include "src/Core/BandMatrix.h"
 
 #include "src/Core/BooleanRedux.h"
diff --git a/Eigen/src/Core/SolveTriangular.h b/Eigen/src/Core/SolveTriangular.h
index abbf57553..b950d2c31 100644
--- a/Eigen/src/Core/SolveTriangular.h
+++ b/Eigen/src/Core/SolveTriangular.h
@@ -27,6 +27,15 @@
 
 namespace internal {
 
+// Forward declarations:
+// The following two routines are implemented in the products/TriangularSolver*.h files
+template<typename LhsScalar, typename RhsScalar, typename Index, int Mode, bool Conjugate, int StorageOrder>
+struct triangular_solve_vector;
+
+template <typename Scalar, typename Index, int Side, int Mode, bool Conjugate, int TriStorageOrder, int OtherStorageOrder>
+struct triangular_solve_matrix;
+
+// small helper struct extracting some traits on the underlying solver operation
 template<typename Lhs, typename Rhs, int Side>
 class trsolve_traits
 {
@@ -51,111 +60,40 @@ template<typename Lhs, typename Rhs,
   >
 struct triangular_solver_selector;
 
-// forward and backward substitution, row-major, rhs is a vector
-template<typename Lhs, typename Rhs, int Mode>
-struct triangular_solver_selector<Lhs,Rhs,OnTheLeft,Mode,NoUnrolling,RowMajor,1>
+template<typename Lhs, typename Rhs, int Mode, int StorageOrder>
+struct triangular_solver_selector<Lhs,Rhs,OnTheLeft,Mode,NoUnrolling,StorageOrder,1>
 {
   typedef typename Lhs::Scalar LhsScalar;
   typedef typename Rhs::Scalar RhsScalar;
   typedef blas_traits<Lhs> LhsProductTraits;
   typedef typename LhsProductTraits::ExtractType ActualLhsType;
-  typedef typename Lhs::Index Index;
-  enum {
-    IsLower = ((Mode&Lower)==Lower)
-  };
-  static void run(const Lhs& lhs, Rhs& other)
+  typedef Map<Matrix<RhsScalar,Dynamic,1>, Aligned> MappedRhs;
+  static void run(const Lhs& lhs, Rhs& rhs)
   {
-    static const Index PanelWidth = EIGEN_TUNE_TRIANGULAR_PANEL_WIDTH;
     ActualLhsType actualLhs = LhsProductTraits::extract(lhs);
 
-    const Index size = lhs.cols();
-    for(Index pi=IsLower ? 0 : size;
-        IsLower ? pi<size : pi>0;
-        IsLower ? pi+=PanelWidth : pi-=PanelWidth)
-    {
-      Index actualPanelWidth = std::min(IsLower ? size - pi : pi, PanelWidth);
-
-      Index r = IsLower ? pi : size - pi; // remaining size
-      if (r > 0)
-      {
-        // let's directly call the low level product function because:
-        // 1 - it is faster to compile
-        // 2 - it is slighlty faster at runtime
-        Index startRow = IsLower ? pi : pi-actualPanelWidth;
-        Index startCol = IsLower ? 0 : pi;
-
-        general_matrix_vector_product<Index,LhsScalar,RowMajor,LhsProductTraits::NeedToConjugate,RhsScalar,false>::run(
-          actualPanelWidth, r,
-          &(actualLhs.const_cast_derived().coeffRef(startRow,startCol)), actualLhs.outerStride(),
-          &(other.coeffRef(startCol)), other.innerStride(),
-          &other.coeffRef(startRow), other.innerStride(),
-          RhsScalar(-1));
-      }
-
-      for(Index k=0; k<actualPanelWidth; ++k)
-      {
-        Index i = IsLower ? pi+k : pi-k-1;
-        Index s = IsLower ? pi : i+1;
-        if (k>0)
-          other.coeffRef(i) -= (lhs.row(i).segment(s,k).transpose().cwiseProduct(other.segment(s,k))).sum();
+    // FIXME find a way to allow an inner stride if packet_traits<Scalar>::size==1
 
-        if(!(Mode & UnitDiag))
-          other.coeffRef(i) /= lhs.coeff(i,i);
-      }
+    bool useRhsDirectly = Rhs::InnerStrideAtCompileTime==1 || rhs.innerStride()==1;
+    RhsScalar* actualRhs;
+    if(useRhsDirectly)
+    {
+      actualRhs = &rhs.coeffRef(0);
     }
-  }
-};
-
-// forward and backward substitution, column-major, rhs is a vector
-template<typename Lhs, typename Rhs, int Mode>
-struct triangular_solver_selector<Lhs,Rhs,OnTheLeft,Mode,NoUnrolling,ColMajor,1>
-{
-  typedef typename Lhs::Scalar LhsScalar;
-  typedef typename Rhs::Scalar RhsScalar;
-  typedef blas_traits<Lhs> LhsProductTraits;
-  typedef typename LhsProductTraits::ExtractType ActualLhsType;
-  typedef typename Lhs::Index Index;
-  enum {
-    IsLower = ((Mode&Lower)==Lower)
-  };
-
-  static void run(const Lhs& lhs, Rhs& other)
-  {
-    static const Index PanelWidth = EIGEN_TUNE_TRIANGULAR_PANEL_WIDTH;
-    ActualLhsType actualLhs = LhsProductTraits::extract(lhs);
-
-    const Index size = lhs.cols();
-    for(Index pi=IsLower ? 0 : size;
-        IsLower ? pi<size : pi>0;
-        IsLower ? pi+=PanelWidth : pi-=PanelWidth)
+    else
     {
-      Index actualPanelWidth = std::min(IsLower ? size - pi : pi, PanelWidth);
-      Index startBlock = IsLower ? pi : pi-actualPanelWidth;
-      Index endBlock = IsLower ? pi + actualPanelWidth : 0;
+      actualRhs = ei_aligned_stack_new(RhsScalar,rhs.size());
+      MappedRhs(actualRhs,rhs.size()) = rhs;
+    }
 
-      for(Index k=0; k<actualPanelWidth; ++k)
-      {
-        Index i = IsLower ? pi+k : pi-k-1;
-        if(!(Mode & UnitDiag))
-          other.coeffRef(i) /= lhs.coeff(i,i);
+      
+    triangular_solve_vector<LhsScalar, RhsScalar, typename Lhs::Index, Mode, LhsProductTraits::NeedToConjugate, StorageOrder>
+      ::run(actualLhs.cols(), actualLhs.data(), actualLhs.outerStride(), actualRhs);
 
-        Index r = actualPanelWidth - k - 1; // remaining size
-        Index s = IsLower ? i+1 : i-r;
-        if (r>0)
-          other.segment(s,r) -= other.coeffRef(i) * Block<Lhs,Dynamic,1>(lhs, s, i, r, 1);
-      }
-      Index r = IsLower ? size - endBlock : startBlock; // remaining size
-      if (r > 0)
-      {
-        // let's directly call the low level product function because:
-        // 1 - it is faster to compile
-        // 2 - it is slighlty faster at runtime
-        general_matrix_vector_product<Index,LhsScalar,ColMajor,LhsProductTraits::NeedToConjugate,RhsScalar,false>::run(
-            r, actualPanelWidth,
-            &(actualLhs.const_cast_derived().coeffRef(endBlock,startBlock)), actualLhs.outerStride(),
-            &other.coeff(startBlock), other.innerStride(),
-            &(other.coeffRef(endBlock, 0)), other.innerStride(), RhsScalar(-1));
-      }
+    if(!useRhsDirectly)
+    {
+      rhs = MappedRhs(actualRhs, rhs.size());
+      ei_aligned_stack_delete(RhsScalar, actualRhs, rhs.size());
     }
   }
 };
@@ -172,8 +110,6 @@ struct triangular_solver_selector<Lhs,Rhs,OnTheRight,Mode,Unrolling,StorageOrder
   }
 };
 
-template <typename Scalar, typename Index, int Side, int Mode, bool Conjugate, int TriStorageOrder, int OtherStorageOrder>
-struct triangular_solve_matrix;
 
 // the rhs is a matrix
 template<typename Lhs, typename Rhs, int Side, int Mode, int StorageOrder>
diff --git a/Eigen/src/Core/products/TriangularSolverVector.h b/Eigen/src/Core/products/TriangularSolverVector.h
new file mode 100644
index 000000000..fcf8bcae0
--- /dev/null
+++ b/Eigen/src/Core/products/TriangularSolverVector.h
@@ -0,0 +1,138 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2008-2010 Gael Guennebaud <gael.guennebaud@inria.fr>
+//
+// 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_TRIANGULAR_SOLVER_VECTOR_H
+#define EIGEN_TRIANGULAR_SOLVER_VECTOR_H
+
+namespace internal {
+
+// forward and backward substitution, row-major, rhs is a vector
+template<typename LhsScalar, typename RhsScalar, typename Index, int Mode, bool Conjugate>
+struct triangular_solve_vector<LhsScalar, RhsScalar, Index, Mode, Conjugate, RowMajor>
+{
+  enum {
+    IsLower = ((Mode&Lower)==Lower)
+  };
+  static void run(int size, const LhsScalar* _lhs, Index lhsStride, RhsScalar* rhs)
+  {
+    typedef Map<Matrix<LhsScalar,Dynamic,Dynamic,RowMajor>, 0, OuterStride<> > LhsMap;
+    const LhsMap lhs(_lhs,size,size,OuterStride<>(lhsStride));
+    typename internal::conditional<
+                          Conjugate,
+                          const CwiseUnaryOp<typename internal::scalar_conjugate_op<LhsScalar>,LhsMap>,
+                          const LhsMap&>
+                        ::type cjLhs(lhs);
+    static const Index PanelWidth = EIGEN_TUNE_TRIANGULAR_PANEL_WIDTH;
+    for(Index pi=IsLower ? 0 : size;
+        IsLower ? pi<size : pi>0;
+        IsLower ? pi+=PanelWidth : pi-=PanelWidth)
+    {
+      Index actualPanelWidth = std::min(IsLower ? size - pi : pi, PanelWidth);
+
+      Index r = IsLower ? pi : size - pi; // remaining size
+      if (r > 0)
+      {
+        // let's directly call the low level product function because:
+        // 1 - it is faster to compile
+        // 2 - it is slighlty faster at runtime
+        Index startRow = IsLower ? pi : pi-actualPanelWidth;
+        Index startCol = IsLower ? 0 : pi;
+
+        general_matrix_vector_product<Index,LhsScalar,RowMajor,Conjugate,RhsScalar,false>::run(
+          actualPanelWidth, r,
+          &(lhs.coeff(startRow,startCol)), lhsStride,
+          rhs + startCol, 1,
+          rhs + startRow, 1,
+          RhsScalar(-1));
+      }
+
+      for(Index k=0; k<actualPanelWidth; ++k)
+      {
+        Index i = IsLower ? pi+k : pi-k-1;
+        Index s = IsLower ? pi   : i+1;
+        if (k>0)
+          rhs[i] -= (cjLhs.row(i).segment(s,k).transpose().cwiseProduct(Map<Matrix<RhsScalar,Dynamic,1> >(rhs+s,k))).sum();
+
+        if(!(Mode & UnitDiag))
+          rhs[i] /= lhs(i,i);
+      }
+    }
+  }
+};
+
+// forward and backward substitution, column-major, rhs is a vector
+template<typename LhsScalar, typename RhsScalar, typename Index, int Mode, bool Conjugate>
+struct triangular_solve_vector<LhsScalar, RhsScalar, Index, Mode, Conjugate, ColMajor>
+{
+  enum {
+    IsLower = ((Mode&Lower)==Lower)
+  };
+  static void run(int size, const LhsScalar* _lhs, Index lhsStride, RhsScalar* rhs)
+  {
+    typedef Map<Matrix<LhsScalar,Dynamic,Dynamic,ColMajor>, 0, OuterStride<> > LhsMap;
+    const LhsMap lhs(_lhs,size,size,OuterStride<>(lhsStride));
+    typename internal::conditional<Conjugate,
+                                   const CwiseUnaryOp<typename internal::scalar_conjugate_op<LhsScalar>,LhsMap>,
+                                   const LhsMap&
+                                  >::type cjLhs(lhs);
+    static const Index PanelWidth = EIGEN_TUNE_TRIANGULAR_PANEL_WIDTH;
+
+    for(Index pi=IsLower ? 0 : size;
+        IsLower ? pi<size : pi>0;
+        IsLower ? pi+=PanelWidth : pi-=PanelWidth)
+    {
+      Index actualPanelWidth = std::min(IsLower ? size - pi : pi, PanelWidth);
+      Index startBlock = IsLower ? pi : pi-actualPanelWidth;
+      Index endBlock = IsLower ? pi + actualPanelWidth : 0;
+
+      for(Index k=0; k<actualPanelWidth; ++k)
+      {
+        Index i = IsLower ? pi+k : pi-k-1;
+        if(!(Mode & UnitDiag))
+          rhs[i] /= cjLhs.coeff(i,i);
+
+        Index r = actualPanelWidth - k - 1; // remaining size
+        Index s = IsLower ? i+1 : i-r;
+        if (r>0)
+          Map<Matrix<RhsScalar,Dynamic,1> >(rhs+s,r) -= rhs[i] * cjLhs.col(i).segment(s,r);
+      }
+      Index r = IsLower ? size - endBlock : startBlock; // remaining size
+      if (r > 0)
+      {
+        // let's directly call the low level product function because:
+        // 1 - it is faster to compile
+        // 2 - it is slighlty faster at runtime
+        general_matrix_vector_product<Index,LhsScalar,ColMajor,Conjugate,RhsScalar,false>::run(
+            r, actualPanelWidth,
+            &(lhs.coeff(endBlock,startBlock)), lhsStride,
+            rhs+startBlock, 1,
+            rhs+endBlock, 1, RhsScalar(-1));
+      }
+    }
+  }
+};
+
+} // end namespace internal
+
+#endif // EIGEN_TRIANGULAR_SOLVER_VECTOR_H