Update Kokkos library in LAMMPS to v3.0

lib/kokkos/example/build_cmake_in_tree/cmake_example.cpp

@@ -0,0 +1,92 @@
+/*
+//@HEADER
+// ************************************************************************
+//
+//                        Kokkos v. 3.0
+//       Copyright (2020) National Technology & Engineering
+//               Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// 1. Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+//
+// 3. Neither the name of the Corporation nor the names of the
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY NTESS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL NTESS OR THE
+// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Questions? Contact Christian R. Trott (crtrott@sandia.gov)
+//
+// ************************************************************************
+//@HEADER
+*/
+
+#include <Kokkos_Core.hpp>
+#include <cstdio>
+
+extern "C" void print_fortran_();
+
+int main(int argc, char* argv[]) {
+  Kokkos::initialize(argc, argv);
+  Kokkos::DefaultExecutionSpace::print_configuration(std::cout);
+
+  if (argc < 2) {
+    fprintf(stderr, "Usage: %s [<kokkos_options>] <size>\n", argv[0]);
+    Kokkos::finalize();
+    exit(1);
+  }
+
+  const long n = strtol(argv[1], NULL, 10);
+
+  printf("Number of even integers from 0 to %ld\n", n - 1);
+
+  Kokkos::Timer timer;
+  timer.reset();
+
+  // Compute the number of even integers from 0 to n-1, in parallel.
+  long count = 0;
+  Kokkos::parallel_reduce(
+      n, KOKKOS_LAMBDA(const long i, long& lcount) { lcount += (i % 2) == 0; },
+      count);
+
+  double count_time = timer.seconds();
+  printf("  Parallel: %ld    %10.6f\n", count, count_time);
+
+  timer.reset();
+
+  // Compare to a sequential loop.
+  long seq_count = 0;
+  for (long i = 0; i < n; ++i) {
+    seq_count += (i % 2) == 0;
+  }
+
+  count_time = timer.seconds();
+  printf("Sequential: %ld    %10.6f\n", seq_count, count_time);
+
+  print_fortran_();
+
+  Kokkos::finalize();
+
+  return (count == seq_count) ? 0 : -1;
+}