Add mcpu=native flag to GNU OpenMP builds

CHANGELOG.md

@@ -6,6 +6,7 @@ All notable changes to this project will be documented in this file.
 ### Added
 - OpenACC flags to build for Volta.
 - Kokkos list CLI argument shows some information about which device will be used.
+- OpenMP GNU compiler now uses native target flag
 
 ### Changed
 - Update SYCL implementation to SYCL 1.2.1 interface.

OpenMP.make

@@ -28,7 +28,7 @@ COMPILER_CLANG = clang++
 COMPILER_XL = xlc++
 CXX = $(COMPILER_$(COMPILER))
 
-FLAGS_GNU = -O3 -std=c++11
+FLAGS_GNU = -O3 -std=c++11 -mcpu=native
 FLAGS_INTEL = -O3 -std=c++11 -xHOST -qopt-streaming-stores=always
 FLAGS_CRAY = -O3 -hstd=c++11
 FLAGS_CLANG = -O3 -std=c++11