Update Kokkos library in LAMMPS to v4.2

lib/kokkos/algorithms/unit_tests/TestStdAlgorithmsTeamMinElement.cpp

@@ -0,0 +1,181 @@
+//@HEADER
+// ************************************************************************
+//
+//                        Kokkos v. 4.0
+//       Copyright (2022) 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.
+//
+// Part of Kokkos, under the Apache License v2.0 with LLVM Exceptions.
+// See https://kokkos.org/LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//@HEADER
+
+#include <TestStdAlgorithmsCommon.hpp>
+#include <algorithm>
+
+namespace Test {
+namespace stdalgos {
+namespace TeamMinElement {
+
+namespace KE = Kokkos::Experimental;
+
+template <class ViewType, class DistancesViewType, class IntraTeamSentinelView>
+struct TestFunctorA {
+  ViewType m_view;
+  DistancesViewType m_distancesView;
+  IntraTeamSentinelView m_intraTeamSentinelView;
+  int m_apiPick;
+
+  TestFunctorA(const ViewType view, const DistancesViewType distancesView,
+               IntraTeamSentinelView intraTeamSentinelView, int apiPick)
+      : m_view(view),
+        m_distancesView(distancesView),
+        m_intraTeamSentinelView(intraTeamSentinelView),
+        m_apiPick(apiPick) {}
+
+  template <class MemberType>
+  KOKKOS_INLINE_FUNCTION void operator()(const MemberType& member) const {
+    const auto myRowIndex = member.league_rank();
+    auto myRowView        = Kokkos::subview(m_view, myRowIndex, Kokkos::ALL());
+    ptrdiff_t resultDist  = 0;
+
+    if (m_apiPick == 0) {
+      auto it =
+          KE::min_element(member, KE::cbegin(myRowView), KE::cend(myRowView));
+      resultDist = KE::distance(KE::cbegin(myRowView), it);
+      Kokkos::single(Kokkos::PerTeam(member), [=, *this]() {
+        m_distancesView(myRowIndex) = resultDist;
+      });
+    }
+
+    else if (m_apiPick == 1) {
+      auto it    = KE::min_element(member, myRowView);
+      resultDist = KE::distance(KE::begin(myRowView), it);
+      Kokkos::single(Kokkos::PerTeam(member), [=, *this]() {
+        m_distancesView(myRowIndex) = resultDist;
+      });
+    }
+#if not defined KOKKOS_ENABLE_OPENMPTARGET
+    else if (m_apiPick == 2) {
+      using value_type = typename ViewType::value_type;
+      auto it =
+          KE::min_element(member, KE::cbegin(myRowView), KE::cend(myRowView),
+                          CustomLessThanComparator<value_type>{});
+      resultDist = KE::distance(KE::cbegin(myRowView), it);
+      Kokkos::single(Kokkos::PerTeam(member), [=, *this]() {
+        m_distancesView(myRowIndex) = resultDist;
+      });
+    }
+
+    else if (m_apiPick == 3) {
+      using value_type = typename ViewType::value_type;
+      auto it          = KE::min_element(member, myRowView,
+                                CustomLessThanComparator<value_type>{});
+      resultDist       = KE::distance(KE::begin(myRowView), it);
+      Kokkos::single(Kokkos::PerTeam(member), [=, *this]() {
+        m_distancesView(myRowIndex) = resultDist;
+      });
+    }
+#endif
+
+    // store result of checking if all members have their local
+    // values matching the one stored in m_distancesView
+    member.team_barrier();
+    const bool intraTeamCheck = team_members_have_matching_result(
+        member, resultDist, m_distancesView(myRowIndex));
+    Kokkos::single(Kokkos::PerTeam(member), [=, *this]() {
+      m_intraTeamSentinelView(myRowIndex) = intraTeamCheck;
+    });
+  }
+};
+
+template <class LayoutTag, class ValueType>
+void test_A(std::size_t numTeams, std::size_t numCols, int apiId) {
+  /* description:
+     team-level KE::min_element on a rank-2 view where
+     data is filled randomly and we use one team per row.
+   */
+
+  // -----------------------------------------------
+  // prepare data
+  // -----------------------------------------------
+  // create a view in the memory space associated with default exespace
+  // with as many rows as the number of teams and fill it with random
+  auto [dataView, cloneOfDataViewBeforeOp_h] =
+      create_random_view_and_host_clone(
+          LayoutTag{}, numTeams, numCols,
+          Kokkos::pair<ValueType, ValueType>{0, 1153}, "dataView");
+
+  // -----------------------------------------------
+  // launch kokkos kernel
+  // -----------------------------------------------
+  using space_t = Kokkos::DefaultExecutionSpace;
+  Kokkos::TeamPolicy<space_t> policy(numTeams, Kokkos::AUTO());
+
+  // each team stores the distance of the returned iterator from the
+  // beginning of the interval that team operates on and then we check
+  // that these distances match the expectation
+  Kokkos::View<std::size_t*> distancesView("distancesView", numTeams);
+  // sentinel to check if all members of the team compute the same result
+  Kokkos::View<bool*> intraTeamSentinelView("intraTeamSameResult", numTeams);
+
+  // use CTAD for functor
+  TestFunctorA fnc(dataView, distancesView, intraTeamSentinelView, apiId);
+  Kokkos::parallel_for(policy, fnc);
+
+  // -----------------------------------------------
+  // run std algo and check
+  // -----------------------------------------------
+  // here I can use cloneOfDataViewBeforeOp_h to run std algo on
+  // since that contains a valid copy of the data
+  auto distancesView_h         = create_host_space_copy(distancesView);
+  auto intraTeamSentinelView_h = create_host_space_copy(intraTeamSentinelView);
+  auto dataViewAfterOp_h       = create_host_space_copy(dataView);
+  for (std::size_t i = 0; i < cloneOfDataViewBeforeOp_h.extent(0); ++i) {
+    auto myRow = Kokkos::subview(cloneOfDataViewBeforeOp_h, i, Kokkos::ALL());
+
+    std::size_t stdDistance = 0;
+    if (apiId <= 1) {
+      auto it     = std::min_element(KE::cbegin(myRow), KE::cend(myRow));
+      stdDistance = KE::distance(KE::cbegin(myRow), it);
+    } else {
+      auto it     = std::min_element(KE::cbegin(myRow), KE::cend(myRow),
+                                 CustomLessThanComparator<value_type>{});
+      stdDistance = KE::distance(KE::cbegin(myRow), it);
+    }
+    ASSERT_EQ(stdDistance, distancesView_h(i));
+    ASSERT_TRUE(intraTeamSentinelView_h(i));
+  }
+
+  // dataView should remain unchanged
+  expect_equal_host_views(cloneOfDataViewBeforeOp_h, dataViewAfterOp_h);
+}
+
+template <class LayoutTag, class ValueType>
+void run_all_scenarios() {
+  for (int numTeams : teamSizesToTest) {
+    for (const auto& numCols : {0, 1, 2, 13, 101, 1444, 5113}) {
+      // for OpenMPTarget we need to avod api accepting a custom
+      // comparator because it is not supported
+      for (int apiId : {0, 1, 2, 3}) {
+        test_A<LayoutTag, ValueType>(numTeams, numCols, apiId);
+      }
+    }
+  }
+}
+
+TEST(std_algorithms_min_element_team_test, test) {
+#if not defined KOKKOS_ENABLE_OPENMPTARGET
+  run_all_scenarios<DynamicTag, int>();
+  run_all_scenarios<StridedTwoRowsTag, double>();
+  run_all_scenarios<StridedThreeRowsTag, int>();
+#endif
+}
+
+}  // namespace TeamMinElement
+}  // namespace stdalgos
+}  // namespace Test