From fa2fcb4895a4ae12cb28003e646c736d013e68e8 Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Thu, 7 Feb 2019 16:07:08 +0100
Subject: [PATCH] Backed out changeset 4c0fa6ce0f81ce67dd6723528ddf72f66ae92ba2

---
 Eigen/src/Core/products/GeneralMatrixMatrix.h | 174 ++++--------------
 1 file changed, 37 insertions(+), 137 deletions(-)

diff --git a/Eigen/src/Core/products/GeneralMatrixMatrix.h b/Eigen/src/Core/products/GeneralMatrixMatrix.h
index 4bcccd326..f49abcad5 100644
--- a/Eigen/src/Core/products/GeneralMatrixMatrix.h
+++ b/Eigen/src/Core/products/GeneralMatrixMatrix.h
@@ -404,146 +404,26 @@ class gemm_blocking_space<StorageOrder,_LhsScalar,_RhsScalar,MaxRows, MaxCols, M
 
 namespace internal {
 
-template <typename Lhs, typename Rhs, typename Dest,
-          bool MultipleRowsAtCompileTime =
-              (Lhs::RowsAtCompileTime > 1 || Dest::RowsAtCompileTime > 1),
-          bool MultipleColsAtCompileTime =
-              (Rhs::ColsAtCompileTime > 1 || Dest::ColsAtCompileTime > 1)>
-struct gemm_selector {
-  typedef typename Product<Lhs,Rhs>::Scalar Scalar;
-
-  typedef internal::blas_traits<Lhs> LhsBlasTraits;
-  typedef typename LhsBlasTraits::DirectLinearAccessType ActualLhsType;
-  typedef typename internal::remove_all<ActualLhsType>::type ActualLhsTypeCleaned;
-
-  typedef internal::blas_traits<Rhs> RhsBlasTraits;
-  typedef typename RhsBlasTraits::DirectLinearAccessType ActualRhsType;
-  typedef typename internal::remove_all<ActualRhsType>::type ActualRhsTypeCleaned;
-
-  static void run(Dest& dst, const Lhs& a_lhs, const Rhs& a_rhs, const Scalar& alpha)
-  {
-    if (a_rhs.cols() != 1 && a_lhs.rows() != 1) {
-      gemm_selector<Lhs, Rhs, Dest, true, true>::run(dst, a_lhs, a_rhs, alpha);
-    } else if (a_rhs.cols() == 1) {
-      // matrix * vector.
-      internal::gemv_dense_selector<OnTheRight,
-                                    (int(ActualLhsTypeCleaned::Flags)&RowMajorBit) ? RowMajor : ColMajor,
-                                    bool(internal::blas_traits<ActualLhsTypeCleaned>::HasUsableDirectAccess)
-                                    >::run(a_lhs, a_rhs.col(0), dst, alpha);
-    } else {
-      // vector * matrix.
-      internal::gemv_dense_selector<OnTheLeft,
-                                    (int(ActualRhsTypeCleaned::Flags)&RowMajorBit) ? RowMajor : ColMajor,
-                                    bool(internal::blas_traits<ActualRhsTypeCleaned>::HasUsableDirectAccess)
-                                    >::run(a_lhs.row(0), a_rhs, dst, alpha);
-    }
-  }
-};
-
-template <typename Lhs, typename Rhs, typename Dest>
-struct gemm_selector<Lhs, Rhs, Dest, true, false> {
-  typedef typename Product<Lhs,Rhs>::Scalar Scalar;
-
-  typedef internal::blas_traits<Lhs> LhsBlasTraits;
-  typedef typename LhsBlasTraits::DirectLinearAccessType ActualLhsType;
-  typedef typename internal::remove_all<ActualLhsType>::type ActualLhsTypeCleaned;
-
-  static void run(Dest& dst, const Lhs& a_lhs, const Rhs& a_rhs, const Scalar& alpha)
-  {
-    if (a_rhs.cols() != 1 && a_lhs.rows() != 1) {
-      gemm_selector<Lhs, Rhs, Dest, true, true>::run(dst, a_lhs, a_rhs, alpha);
-    } else {
-      // matrix * vector.
-      internal::gemv_dense_selector<OnTheRight,
-                                    (int(ActualLhsTypeCleaned::Flags)&RowMajorBit) ? RowMajor : ColMajor,
-                                    bool(internal::blas_traits<ActualLhsTypeCleaned>::HasUsableDirectAccess)
-                                    >::run(a_lhs, a_rhs.col(0), dst, alpha);
-    }
-  }
-};
-
-template <typename Lhs, typename Rhs, typename Dest>
-struct gemm_selector<Lhs, Rhs, Dest, false, true> {
-  typedef typename Product<Lhs,Rhs>::Scalar Scalar;
-
-  typedef internal::blas_traits<Rhs> RhsBlasTraits;
-  typedef typename RhsBlasTraits::DirectLinearAccessType ActualRhsType;
-  typedef typename internal::remove_all<ActualRhsType>::type ActualRhsTypeCleaned;
-
-  static void run(Dest& dst, const Lhs& a_lhs, const Rhs& a_rhs, const Scalar& alpha)
-  {
-    if (a_rhs.cols() != 1 && a_lhs.rows() != 1) {
-      gemm_selector<Lhs, Rhs, Dest, true, true>::run(dst, a_lhs, a_rhs, alpha);
-    } else {
-      // vector * matrix.
-      internal::gemv_dense_selector<OnTheLeft,
-                                    (int(ActualRhsTypeCleaned::Flags)&RowMajorBit) ? RowMajor : ColMajor,
-                                    bool(internal::blas_traits<ActualRhsTypeCleaned>::HasUsableDirectAccess)
-                                    >::run(a_lhs.row(0), a_rhs, dst, alpha);
-    }
-  }
-};
-
-template <typename Lhs, typename Rhs, typename Dest>
-struct gemm_selector<Lhs, Rhs, Dest, true, true> {
-  typedef typename Product<Lhs, Rhs>::Scalar Scalar;
-  typedef typename Lhs::Scalar LhsScalar;
-  typedef typename Rhs::Scalar RhsScalar;
-
-  typedef internal::blas_traits<Lhs> LhsBlasTraits;
-  typedef typename LhsBlasTraits::DirectLinearAccessType ActualLhsType;
-  typedef
-      typename internal::remove_all<ActualLhsType>::type ActualLhsTypeCleaned;
-
-  typedef internal::blas_traits<Rhs> RhsBlasTraits;
-  typedef typename RhsBlasTraits::DirectLinearAccessType ActualRhsType;
-  typedef
-      typename internal::remove_all<ActualRhsType>::type ActualRhsTypeCleaned;
-
-  enum {
-    MaxDepthAtCompileTime = EIGEN_SIZE_MIN_PREFER_FIXED(
-        Lhs::MaxColsAtCompileTime, Rhs::MaxRowsAtCompileTime)
-  };
-
-  static void run(Dest& dst, const Lhs& a_lhs, const Rhs& a_rhs,
-                  const Scalar& alpha) {
-    Scalar actualAlpha = alpha * LhsBlasTraits::extractScalarFactor(a_lhs) *
-                         RhsBlasTraits::extractScalarFactor(a_rhs);
-    typename internal::add_const_on_value_type<ActualLhsType>::type lhs =
-        LhsBlasTraits::extract(a_lhs);
-    typename internal::add_const_on_value_type<ActualRhsType>::type rhs =
-        RhsBlasTraits::extract(a_rhs);
-    typedef internal::gemm_blocking_space<
-        (Dest::Flags & RowMajorBit) ? RowMajor : ColMajor, LhsScalar, RhsScalar,
-        Dest::MaxRowsAtCompileTime, Dest::MaxColsAtCompileTime,
-        MaxDepthAtCompileTime>
-        BlockingType;
-
-    typedef internal::gemm_functor<
-        Scalar, Index,
-        internal::general_matrix_matrix_product<
-            Index, LhsScalar,
-            (ActualLhsTypeCleaned::Flags & RowMajorBit) ? RowMajor : ColMajor,
-            bool(LhsBlasTraits::NeedToConjugate), RhsScalar,
-            (ActualRhsTypeCleaned::Flags & RowMajorBit) ? RowMajor : ColMajor,
-            bool(RhsBlasTraits::NeedToConjugate),
-            (Dest::Flags & RowMajorBit) ? RowMajor : ColMajor>,
-        ActualLhsTypeCleaned, ActualRhsTypeCleaned, Dest, BlockingType>
-        GemmFunctor;
-
-    BlockingType blocking(dst.rows(), dst.cols(), lhs.cols(), 1, true);
-    internal::parallelize_gemm<(Dest::MaxRowsAtCompileTime > 32 ||
-                                Dest::MaxRowsAtCompileTime == Dynamic)>(
-        GemmFunctor(lhs, rhs, dst, actualAlpha, blocking), a_lhs.rows(),
-        a_rhs.cols(), a_lhs.cols(), Dest::Flags & RowMajorBit);
-  }
-};
-
 template<typename Lhs, typename Rhs>
 struct generic_product_impl<Lhs,Rhs,DenseShape,DenseShape,GemmProduct>
   : generic_product_impl_base<Lhs,Rhs,generic_product_impl<Lhs,Rhs,DenseShape,DenseShape,GemmProduct> >
 {
   typedef typename Product<Lhs,Rhs>::Scalar Scalar;
+  typedef typename Lhs::Scalar LhsScalar;
+  typedef typename Rhs::Scalar RhsScalar;
+
+  typedef internal::blas_traits<Lhs> LhsBlasTraits;
+  typedef typename LhsBlasTraits::DirectLinearAccessType ActualLhsType;
+  typedef typename internal::remove_all<ActualLhsType>::type ActualLhsTypeCleaned;
+
+  typedef internal::blas_traits<Rhs> RhsBlasTraits;
+  typedef typename RhsBlasTraits::DirectLinearAccessType ActualRhsType;
+  typedef typename internal::remove_all<ActualRhsType>::type ActualRhsTypeCleaned;
+
+  enum {
+    MaxDepthAtCompileTime = EIGEN_SIZE_MIN_PREFER_FIXED(Lhs::MaxColsAtCompileTime,Rhs::MaxRowsAtCompileTime)
+  };
+
   typedef generic_product_impl<Lhs,Rhs,DenseShape,DenseShape,CoeffBasedProductMode> lazyproduct;
 
   template<typename Dst>
@@ -570,7 +450,7 @@ struct generic_product_impl<Lhs,Rhs,DenseShape,DenseShape,GemmProduct>
     if((rhs.rows()+dst.rows()+dst.cols())<EIGEN_GEMM_TO_COEFFBASED_THRESHOLD && rhs.rows()>0)
       lazyproduct::eval_dynamic(dst, lhs, rhs, internal::add_assign_op<typename Dst::Scalar,Scalar>());
     else
-      scaleAndAddTo(dst, lhs, rhs, Scalar(1));
+      scaleAndAddTo(dst,lhs, rhs, Scalar(1));
   }
 
   template<typename Dst>
@@ -589,7 +469,27 @@ struct generic_product_impl<Lhs,Rhs,DenseShape,DenseShape,GemmProduct>
     if(a_lhs.cols()==0 || a_lhs.rows()==0 || a_rhs.cols()==0)
       return;
 
-    gemm_selector<Lhs, Rhs, Dest>::run(dst, a_lhs, a_rhs, alpha);
+    typename internal::add_const_on_value_type<ActualLhsType>::type lhs = LhsBlasTraits::extract(a_lhs);
+    typename internal::add_const_on_value_type<ActualRhsType>::type rhs = RhsBlasTraits::extract(a_rhs);
+
+    Scalar actualAlpha = alpha * LhsBlasTraits::extractScalarFactor(a_lhs)
+                               * RhsBlasTraits::extractScalarFactor(a_rhs);
+
+    typedef internal::gemm_blocking_space<(Dest::Flags&RowMajorBit) ? RowMajor : ColMajor,LhsScalar,RhsScalar,
+            Dest::MaxRowsAtCompileTime,Dest::MaxColsAtCompileTime,MaxDepthAtCompileTime> BlockingType;
+
+    typedef internal::gemm_functor<
+      Scalar, Index,
+      internal::general_matrix_matrix_product<
+        Index,
+        LhsScalar, (ActualLhsTypeCleaned::Flags&RowMajorBit) ? RowMajor : ColMajor, bool(LhsBlasTraits::NeedToConjugate),
+        RhsScalar, (ActualRhsTypeCleaned::Flags&RowMajorBit) ? RowMajor : ColMajor, bool(RhsBlasTraits::NeedToConjugate),
+        (Dest::Flags&RowMajorBit) ? RowMajor : ColMajor>,
+      ActualLhsTypeCleaned, ActualRhsTypeCleaned, Dest, BlockingType> GemmFunctor;
+
+    BlockingType blocking(dst.rows(), dst.cols(), lhs.cols(), 1, true);
+    internal::parallelize_gemm<(Dest::MaxRowsAtCompileTime>32 || Dest::MaxRowsAtCompileTime==Dynamic)>
+        (GemmFunctor(lhs, rhs, dst, actualAlpha, blocking), a_lhs.rows(), a_rhs.cols(), a_lhs.cols(), Dest::Flags&RowMajorBit);
   }
 };