Misc improvements for fixed size tensors

unsupported/Eigen/CXX11/src/Tensor/TensorFixedSize.h

diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorFixedSize.h b/unsupported/Eigen/CXX11/src/Tensor/TensorFixedSize.h
index 1af2d7b..94b3f95 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorFixedSize.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorFixedSize.h
@@ -42,7 +42,9 @@
     enum {
       IsAligned = bool(EIGEN_ALIGN),
       PacketAccess = (internal::packet_traits<Scalar>::size > 1),
-    };
+      Layout = Options_ & RowMajor ? RowMajor : ColMajor,
+      CoordAccess = true,
+   };
 
   typedef Dimensions_ Dimensions;
   static const std::size_t NumIndices = Dimensions::count;
@@ -51,11 +53,12 @@
   TensorStorage<Scalar, NumIndices, Dimensions::total_size, Options, Dimensions> m_storage;
 
   public:
-    EIGEN_STRONG_INLINE Index                    dimension(std::size_t n) const { return m_storage.dimensions()[n]; }
-    EIGEN_STRONG_INLINE const Dimensions&        dimensions()             const { return m_storage.dimensions(); }
-    EIGEN_STRONG_INLINE Index                    size()                   const { return m_storage.size(); }
-    EIGEN_STRONG_INLINE Scalar                   *data()                        { return m_storage.data(); }
-    EIGEN_STRONG_INLINE const Scalar             *data()                  const { return m_storage.data(); }
+    EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Index                      rank()                   const { return NumIndices; }
+    EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Index                    dimension(std::size_t n) const { return m_storage.dimensions()[n]; }
+    EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions&        dimensions()             const { return m_storage.dimensions(); }
+    EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Index                    size()                   const { return m_storage.size(); }
+    EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Scalar                   *data()                        { return m_storage.data(); }
+    EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar             *data()                  const { return m_storage.data(); }
 
     // This makes EIGEN_INITIALIZE_COEFFS_IF_THAT_OPTION_IS_ENABLED
     // work, because that uses base().coeffRef() - and we don't yet
@@ -187,6 +190,23 @@
     {
     }
 
+#ifdef EIGEN_HAVE_RVALUE_REFERENCES
+    inline TensorFixedSize(Self&& other)
+      : m_storage(other.m_storage)
+    {
+    }
+#endif
+
+    EIGEN_DEVICE_FUNC
+    EIGEN_STRONG_INLINE TensorFixedSize& operator=(const TensorFixedSize& other)
+    {
+      // FIXME: check that the dimensions of other match the dimensions of *this.
+      // Unfortunately this isn't possible yet when the rhs is an expression.
+      typedef TensorAssignOp<Self, const TensorFixedSize> Assign;
+      Assign assign(*this, other);
+      internal::TensorExecutor<const Assign, DefaultDevice>::run(assign, DefaultDevice());
+      return *this;
+    }
     template<typename OtherDerived>
     EIGEN_DEVICE_FUNC
     EIGEN_STRONG_INLINE TensorFixedSize& operator=(const OtherDerived& other)

unsupported/test/cxx11_tensor_fixed_size.cpp

diff --git a/unsupported/test/cxx11_tensor_fixed_size.cpp b/unsupported/test/cxx11_tensor_fixed_size.cpp
index 99ffc7f..8a27f5a 100644
--- a/unsupported/test/cxx11_tensor_fixed_size.cpp
+++ b/unsupported/test/cxx11_tensor_fixed_size.cpp
@@ -32,13 +32,14 @@
   vec1(5) = 42.0; vec2(5) = 5.0;
 
   float data3[6];
-  TensorMap<TensorFixedSize<float, Sizes<6> > > vec3(data3, Sizes<6>());
+  TensorMap<TensorFixedSize<float, Sizes<6> > > vec3(data3, 6);
   vec3 = vec1.sqrt();
   float data4[6];
-  TensorMap<TensorFixedSize<float, Sizes<6>, RowMajor> > vec4(data4, Sizes<6>());
+  TensorMap<TensorFixedSize<float, Sizes<6>, RowMajor> > vec4(data4, 6);
   vec4 = vec2.sqrt();
 
   VERIFY_IS_EQUAL((vec3.size()), 6);
+  VERIFY_IS_EQUAL(vec3.rank(), 1);
   //  VERIFY_IS_EQUAL((vec3.dimensions()[0]), 6);
   //  VERIFY_IS_EQUAL((vec3.dimension(0)), 6);
 
@@ -68,11 +69,12 @@
 static void test_2d()
 {
   float data1[6];
-  TensorMap<TensorFixedSize<float, Sizes<2, 3> >> mat1(data1, Sizes<2, 3>());
+  TensorMap<TensorFixedSize<float, Sizes<2, 3> >> mat1(data1,2,3);
   float data2[6];
-  TensorMap<TensorFixedSize<float, Sizes<2, 3>, RowMajor>> mat2(data2, Sizes<2, 3>());
+  TensorMap<TensorFixedSize<float, Sizes<2, 3>, RowMajor>> mat2(data2,2,3);
 
   VERIFY_IS_EQUAL((mat1.size()), 2*3);
+  VERIFY_IS_EQUAL(mat1.rank(), 2);
   //  VERIFY_IS_EQUAL((mat1.dimension(0)), 2);
   //  VERIFY_IS_EQUAL((mat1.dimension(1)), 3);
 
@@ -120,6 +122,7 @@
   TensorFixedSize<float, Sizes<2, 3, 7>, RowMajor> mat2;
 
   VERIFY_IS_EQUAL((mat1.size()), 2*3*7);
+  VERIFY_IS_EQUAL(mat1.rank(), 3);
   //  VERIFY_IS_EQUAL((mat1.dimension(0)), 2);
   //  VERIFY_IS_EQUAL((mat1.dimension(1)), 3);
   //  VERIFY_IS_EQUAL((mat1.dimension(2)), 7);
@@ -166,7 +169,7 @@
   for (int i = 0; i < 2; ++i) {
     for (int j = 0; j < 3; ++j) {
       for (int k = 0; k < 7; ++k) {
-        mat1(array<ptrdiff_t, 3>{{i,j,k}}) = val;
+        mat1(i,j,k) = val;
         val += 1.0;
       }
     }