Added stuff for the device layer for testing GPU-GPU MPI. This is a quick and dirty solution which is primarily meant for benchmarking/verification. Figuring out what the MPI interface should look like is more challenging and is not the priority right now

src/mpitest/main.cc

@@ -0,0 +1,29 @@
+/*
+    Copyright (C) 2014-2019, Johannes Pekkilae, Miikka Vaeisalae.
+
+    This file is part of Astaroth.
+
+    Astaroth is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Astaroth is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with Astaroth.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+    Running: mpirun -np <num processes> <executable>
+*/
+#include "astaroth.h"
+
+int
+main(void)
+{
+    acDeviceRunMPITest();
+    return EXIT_SUCCESS;
+}