Add Fastor library

noarch/include/Fastor/backend/inner.h

@@ -0,0 +1,27 @@
+#ifndef INNER_H_
+#define INNER_H_
+
+#include "Fastor/meta/meta.h"
+#include "Fastor/backend/doublecontract.h"
+
+namespace Fastor {
+
+/* The dependency on doublecontract here is on purpose
+    as it creates a necessary layer of indirection to avoid
+    the case where M == 0
+*/
+template<typename T, size_t M,
+    enable_if_t_<is_greater_v_<M,0>, bool> = false>
+FASTOR_INLINE T _inner(const T* FASTOR_RESTRICT a, const T* FASTOR_RESTRICT b) {
+    return _doublecontract<T,M,1>(a,b);
+}
+
+template<typename T, size_t M,
+    enable_if_t_<M==0, bool> = false>
+FASTOR_INLINE T _inner(const T* FASTOR_RESTRICT a, const T* FASTOR_RESTRICT b) {
+    return (*a)*(*b);
+}
+
+} // end of namespace Fastor
+
+#endif // INNER_H_