From 823e12708fe93cd459c2da1683a7b8accb9ef4ec Mon Sep 17 00:00:00 2001
From: Tom Deakin <tom.deakin@bristol.ac.uk>
Date: Fri, 21 Oct 2016 10:58:26 +0100
Subject: [PATCH] Add dot kernel to Kokkos

---
 KOKKOSStream.cpp | 17 +++++++++++++++++
 KOKKOSStream.hpp |  1 +
 2 files changed, 18 insertions(+)

diff --git a/KOKKOSStream.cpp b/KOKKOSStream.cpp
index d73f7d5..58dbe94 100644
--- a/KOKKOSStream.cpp
+++ b/KOKKOSStream.cpp
@@ -121,6 +121,23 @@ void KOKKOSStream<T>::triad()
   Kokkos::fence();
 }
 
+template <class T>
+T KOKKOSStream<T>::dot()
+{
+  View<double *, DEVICE> a(*d_a);
+  View<double *, DEVICE> b(*d_b);
+
+  T sum = 0.0;
+
+  parallel_reduce(array_size, KOKKOS_LAMBDA (const int index, double &tmp)
+  {
+    tmp += a[index] * b[index];
+  }, sum);
+
+  return sum;
+
+}
+
 void listDevices(void)
 {
   std::cout << "This is not the device you are looking for.";
diff --git a/KOKKOSStream.hpp b/KOKKOSStream.hpp
index d2b9665..013deff 100644
--- a/KOKKOSStream.hpp
+++ b/KOKKOSStream.hpp
@@ -47,6 +47,7 @@ class KOKKOSStream : public Stream<T>
     virtual void add() override;
     virtual void mul() override;
     virtual void triad() override;
+    virtual T dot() override;
 
     virtual void write_arrays(
             const std::vector<T>& a, const std::vector<T>& b, const std::vector<T>& c) override;