Moved some utilities to TensorMeta.h to make it easier to reuse them accross several tensor operations.

Created the TensorDimensionList class to encode the list of all the dimensions of a tensor of rank n. This could be done using TensorIndexList, however TensorIndexList require cxx11 which isn't yet supported as widely as we'd like.

5 files changed, 283 insertions, 33 deletions

diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorContraction.h b/unsupported/Eigen/CXX11/src/Tensor/TensorContraction.h
index 270383020..fd2f3abc4 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorContraction.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorContraction.h
@@ -364,14 +364,6 @@ class TensorContractionInputMapper<Scalar, Index, side, Tensor, nocontract_t, co
 };
 
 
-template <size_t n> struct max_n_1 {
-  static const size_t size = n;
-};
-template <> struct max_n_1<0> {
-  static const size_t size = 1;
-};
-
-
 template<typename Dimensions, typename LhsXprType, typename RhsXprType>
 struct traits<TensorContractionOp<Dimensions, LhsXprType, RhsXprType> >
 {
@@ -459,19 +451,6 @@ class TensorContractionOp : public TensorBase<TensorContractionOp<Indices, LhsXp
 };
 
 
-template<bool cond> struct Cond {};
-
-template<typename T1, typename T2> EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE
-const T1& choose(Cond<true>, const T1& first, const T2&) {
-  return first;
-}
-
-template<typename T1, typename T2> EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE
-const T2& choose(Cond<false>, const T1&, const T2& second) {
-  return second;
-}
-
-
 template<typename Derived>
 struct TensorContractionEvaluatorBase
 {
@@ -508,13 +487,13 @@ struct TensorContractionEvaluatorBase
   static const int RDims =
       internal::array_size<typename TensorEvaluator<EvalRightArgType, Device>::Dimensions>::value;
   static const unsigned int ContractDims = internal::array_size<Indices>::value;
-  static const int NumDims = internal::max_n_1<LDims + RDims - 2 * ContractDims>::size;
+  static const int NumDims = max_n_1<LDims + RDims - 2 * ContractDims>::size;
 
   typedef array<Index, LDims> left_dim_mapper_t;
   typedef array<Index, RDims> right_dim_mapper_t;
   typedef array<Index, ContractDims> contract_t;
-  typedef array<Index, internal::max_n_1<LDims - ContractDims>::size> left_nocontract_t;
-  typedef array<Index, internal::max_n_1<RDims - ContractDims>::size> right_nocontract_t;
+  typedef array<Index, max_n_1<LDims - ContractDims>::size> left_nocontract_t;
+  typedef array<Index, max_n_1<RDims - ContractDims>::size> right_nocontract_t;
 
   typedef DSizes<Index, NumDims> Dimensions;
 
@@ -869,10 +848,10 @@ struct TensorEvaluator<const TensorContractionOp<Indices, LeftArgType, RightArgT
   typedef array<Index, RDims> right_dim_mapper_t;
 
   typedef array<Index, ContractDims> contract_t;
-  typedef array<Index, internal::max_n_1<LDims - ContractDims>::size> left_nocontract_t;
-  typedef array<Index, internal::max_n_1<RDims - ContractDims>::size> right_nocontract_t;
+  typedef array<Index, max_n_1<LDims - ContractDims>::size> left_nocontract_t;
+  typedef array<Index, max_n_1<RDims - ContractDims>::size> right_nocontract_t;
 
-  static const int NumDims = internal::max_n_1<LDims + RDims - 2 * ContractDims>::size;
+  static const int NumDims = max_n_1<LDims + RDims - 2 * ContractDims>::size;
 
   // Could we use NumDimensions here?
   typedef DSizes<Index, NumDims> Dimensions;
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorContractionCuda.h b/unsupported/Eigen/CXX11/src/Tensor/TensorContractionCuda.h
index 588770bb4..f6bd949bd 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorContractionCuda.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorContractionCuda.h
@@ -1241,10 +1241,10 @@ struct TensorEvaluator<const TensorContractionOp<Indices, LeftArgType, RightArgT
   typedef array<Index, RDims> right_dim_mapper_t;
 
   typedef array<Index, ContractDims> contract_t;
-  typedef array<Index, internal::max_n_1<LDims - ContractDims>::size> left_nocontract_t;
-  typedef array<Index, internal::max_n_1<RDims - ContractDims>::size> right_nocontract_t;
+  typedef array<Index, max_n_1<LDims - ContractDims>::size> left_nocontract_t;
+  typedef array<Index, max_n_1<RDims - ContractDims>::size> right_nocontract_t;
 
-  static const int NumDims = internal::max_n_1<LDims + RDims - 2 * ContractDims>::size;
+  static const int NumDims = max_n_1<LDims + RDims - 2 * ContractDims>::size;
 
   typedef DSizes<Index, NumDims> Dimensions;
 
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorContractionThreadPool.h b/unsupported/Eigen/CXX11/src/Tensor/TensorContractionThreadPool.h
index ed87d3100..57030229d 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorContractionThreadPool.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorContractionThreadPool.h
@@ -93,10 +93,10 @@ struct TensorEvaluator<const TensorContractionOp<Indices, LeftArgType, RightArgT
   typedef array<Index, RDims> right_dim_mapper_t;
 
   typedef array<Index, ContractDims> contract_t;
-  typedef array<Index, internal::max_n_1<LDims - ContractDims>::size> left_nocontract_t;
-  typedef array<Index, internal::max_n_1<RDims - ContractDims>::size> right_nocontract_t;
+  typedef array<Index, max_n_1<LDims - ContractDims>::size> left_nocontract_t;
+  typedef array<Index, max_n_1<RDims - ContractDims>::size> right_nocontract_t;
 
-  static const int NumDims = internal::max_n_1<LDims + RDims - 2 * ContractDims>::size;
+  static const int NumDims = max_n_1<LDims + RDims - 2 * ContractDims>::size;
 
   typedef DSizes<Index, NumDims> Dimensions;
 
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorDimensionList.h b/unsupported/Eigen/CXX11/src/Tensor/TensorDimensionList.h
new file mode 100644
index 000000000..19e922f92
--- /dev/null
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorDimensionList.h
@@ -0,0 +1,235 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2015 Benoit Steiner <benoit.steiner.goog@gmail.com>
+//
+// This Source Code Form is subject to the terms of the Mozilla
+// Public License v. 2.0. If a copy of the MPL was not distributed
+// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#ifndef EIGEN_CXX11_TENSOR_TENSOR_DIMENSION_LIST_H
+#define EIGEN_CXX11_TENSOR_TENSOR_DIMENSION_LIST_H
+
+namespace Eigen {
+
+/** \internal
+  *
+  * \class TensorDimensionList
+  * \ingroup CXX11_Tensor_Module
+  *
+  * \brief Special case of tensor index list used to list all the dimensions of a tensor of rank n.
+  *
+  * \sa Tensor
+  */
+
+template <typename Index, std::size_t Rank> struct DimensionList {
+  const Index operator[] (const Index i) const { return i; }
+};
+
+namespace internal {
+
+template<typename Index, std::size_t Rank> struct array_size<DimensionList<Index, Rank> > {
+  static const size_t value = Rank;
+};
+template<typename Index, std::size_t Rank> struct array_size<const DimensionList<Index, Rank> > {
+  static const size_t value = Rank;
+};
+
+template<DenseIndex n, typename Index, std::size_t Rank> const Index array_get(DimensionList<Index, Rank>& a) {
+  return n;
+}
+template<DenseIndex n, typename Index, std::size_t Rank> const Index array_get(const DimensionList<Index, Rank>& a) {
+  return n;
+}
+
+
+#if defined(EIGEN_HAS_CONSTEXPR)
+template <typename Index, std::size_t Rank>
+struct index_known_statically<DimensionList<Index, Rank> > {
+  constexpr bool operator() (const DenseIndex) const {
+    return true;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct index_known_statically<const DimensionList<Index, Rank> > {
+  constexpr bool operator() (const DenseIndex) const {
+    return true;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct all_indices_known_statically<DimensionList<Index, Rank> > {
+  constexpr bool operator() () const {
+    return true;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct all_indices_known_statically<const DimensionList<Index, Rank> > {
+  constexpr bool operator() () const {
+    return true;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct indices_statically_known_to_increase<DimensionList<Index, Rank> > {
+  constexpr bool operator() () const {
+    return true;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct indices_statically_known_to_increase<const DimensionList<Index, Rank> > {
+  constexpr bool operator() () const {
+    return true;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct index_statically_eq<DimensionList<Index, Rank> > {
+  constexpr bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return i == value;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct index_statically_eq<const DimensionList<Index, Rank> > {
+  constexpr bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return i == value;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct index_statically_ne<DimensionList<Index, Rank> > {
+  constexpr bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return i != value;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct index_statically_ne<const DimensionList<Index, Rank> > {
+  constexpr bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return i != value;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct index_statically_gt<DimensionList<Index, Rank> > {
+  constexpr bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return i > value;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct index_statically_gt<const DimensionList<Index, Rank> > {
+  constexpr bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return i > value;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct index_statically_lt<DimensionList<Index, Rank> > {
+  constexpr bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return i < value;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct index_statically_lt<const DimensionList<Index, Rank> > {
+  constexpr bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return i < value;
+  }
+};
+
+#else
+template <typename Index, std::size_t Rank>
+struct index_known_statically<DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() (const DenseIndex) const {
+    return true;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct index_known_statically<const DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() (const DenseIndex) const {
+    return true;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct all_indices_known_statically<DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() () const {
+    return true;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct all_indices_known_statically<const DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() () const {
+    return true;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct indices_statically_known_to_increase<DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() () const {
+    return true;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct indices_statically_known_to_increase<const DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() () const {
+    return true;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct index_statically_eq<DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return false;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct index_statically_eq<const DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return false;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct index_statically_ne<DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return false;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct index_statically_ne<const DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return false;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct index_statically_gt<DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return false;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct index_statically_gt<const DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return false;
+  }
+};
+
+template <typename Index, std::size_t Rank>
+struct index_statically_lt<DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return false;
+  }
+};
+template <typename Index, std::size_t Rank>
+struct index_statically_lt<const DimensionList<Index, Rank> > {
+  EIGEN_ALWAYS_INLINE bool operator() (const DenseIndex i, const DenseIndex value) const {
+    return false;
+  }
+};
+#endif
+
+}  // end namespace internal
+}  // end namespace Eigen
+
+
+#endif // EIGEN_CXX11_TENSOR_TENSOR_DIMENSION_LIST_H
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorMeta.h b/unsupported/Eigen/CXX11/src/Tensor/TensorMeta.h
new file mode 100644
index 000000000..78feb85cd
--- /dev/null
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorMeta.h
@@ -0,0 +1,36 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2015 Benoit Steiner <benoit.steiner.goog@gmail.com>
+//
+// This Source Code Form is subject to the terms of the Mozilla
+// Public License v. 2.0. If a copy of the MPL was not distributed
+// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#ifndef EIGEN_CXX11_TENSOR_TENSOR_META_H
+#define EIGEN_CXX11_TENSOR_TENSOR_META_H
+
+namespace Eigen {
+
+template<bool cond> struct Cond {};
+
+template<typename T1, typename T2> EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE
+const T1& choose(Cond<true>, const T1& first, const T2&) {
+  return first;
+}
+
+template<typename T1, typename T2> EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE
+const T2& choose(Cond<false>, const T1&, const T2& second) {
+  return second;
+}
+
+template <size_t n> struct max_n_1 {
+  static const size_t size = n;
+};
+template <> struct max_n_1<0> {
+  static const size_t size = 1;
+};
+
+}  // namespace Eigen
+
+#endif  // EIGEN_CXX11_TENSOR_TENSOR_META_H