[!321] Add a bit more traits concept around the vector class library

Merge branch 'feature/vcl-traits-stuff' into 'master'

ref:extensions/dune-codegen The VCL does not export enough information about
its types to reason about them, when they are used as template parameters. In
the long run, a proper solution will be needed I guess\...

See merge request [extensions/dune-codegen!321]

  [extensions/dune-codegen!321]: gitlab.dune-project.org/extensions/dune-codegen/merge_requests/321

dune/codegen/common/simdtraits.hh

+#ifndef DUNE_CODEGEN_COMMON_SIMD_TRAITS_HH
+#define DUNE_CODEGEN_COMMON_SIMD_TRAITS_HH
+
+/** This is just the declaration of the traits classes, specialization for VCL and
+ *  OpCounter VCL are elsewhere.
+ */
+
+template<typename T>
+struct base_floatingpoint
+{};
+
+template<typename T>
+struct simd_size
+{};
+
+#endif

dune/codegen/common/vcltraits.hh

+#ifndef DUNE_CODEGEN_COMMON_VCLTRAITS_HH
+#define DUNE_CODEGEN_COMMON_VCLTRAITS_HH
+
+/** A collection of traits tools for the Vector Class Library */
+
+#include<dune/codegen/common/vectorclass.hh>
+
+
+template<>
+struct base_floatingpoint<Vec2d>
+{
+  using value = double;
+};
+
+template<>
+struct base_floatingpoint<Vec4f>
+{
+  using value = float;
+};
+
+template<>
+struct simd_size<Vec2d>
+{
+  static constexpr std::size_t value = 2;
+};
+
+template<>
+struct simd_size<Vec4f>
+{
+  static constexpr std::size_t value = 4;
+};
+
+#if MAX_VECTOR_SIZE >= 256
+template<>
+struct base_floatingpoint<Vec4d>
+{
+  using value = double;
+};
+
+template<>
+struct base_floatingpoint<Vec8f>
+{
+  using value = float;
+};
+
+template<>
+struct simd_size<Vec4d>
+{
+  static constexpr std::size_t value = 4;
+};
+
+template<>
+struct simd_size<Vec8f>
+{
+  static constexpr std::size_t value = 8;
+};
+#endif
+
+#if MAX_VECTOR_SIZE >= 512
+template<>
+struct base_floatingpoint<Vec8d>
+{
+  using value = double;
+};
+
+template<>
+struct base_floatingpoint<Vec16f>
+{
+  using value = float;
+};
+
+template<>
+struct simd_size<Vec8d>
+{
+  static constexpr std::size_t value = 8;
+};
+
+template<>
+struct simd_size<Vec16f>
+{
+  static constexpr std::size_t value = 16;
+};
+
+#endif
+
+#endif

dune/codegen/common/vectorclass.hh

 #ifndef DUNE_CODEGEN_COMMON_VECTORCLASS_HH
 #define DUNE_CODEGEN_COMMON_VECTORCLASS_HH
 
-
-template<typename T>
-struct base_floatingpoint
-{};
+#include<dune/codegen/common/simdtraits.hh>
 
 #ifdef ENABLE_COUNTER
+
 #if HAVE_DUNE_OPCOUNTER
 #include<dune/opcounter/vectorclass.hh>
-
-template<typename F, int size>
-struct base_floatingpoint<OpCounter::impl::OpCounterVector<F, size>>
-{
-  using value = OpCounter::OpCounter<F>;
-};
-
-
 #else
 #error "dune-opcounter is needed for opcounted vector types"
 #endif
+
 #else
+
 #include<dune/codegen/vectorclass/vectorclass.h>
 #include<dune/codegen/vectorclass/vectormath_exp.h>
 #include<dune/codegen/vectorclass/vectormath_hyp.h>
 #include<dune/codegen/vectorclass/vectormath_trig.h>
-
-template<>
-struct base_floatingpoint<Vec2d>
-{
-  using value = double;
-};
-
-template<>
-struct base_floatingpoint<Vec4f>
-{
-  using value = float;
-};
-
-
-#if MAX_VECTOR_SIZE >= 256
-template<>
-struct base_floatingpoint<Vec4d>
-{
-  using value = double;
-};
-
-template<>
-struct base_floatingpoint<Vec8f>
-{
-  using value = float;
-};
-#endif
-
-#if MAX_VECTOR_SIZE >= 512
-template<>
-struct base_floatingpoint<Vec8d>
-{
-  using value = double;
-};
-
-template<>
-struct base_floatingpoint<Vec16f>
-{
-  using value = float;
-};
-#endif
+#include<dune/codegen/common/vcltraits.hh>
 
 #endif