get_vtx_patches without kokkos

src/CMakeLists.txt

@@ -409,15 +409,17 @@ if(BUILD_TESTING)
   osh_add_exe(arrayops_test)
   osh_add_exe(sort_test)
   osh_add_exe(unit_math)
+
+  osh_add_exe(test_patches)
+  if(Omega_h_USE_MPI)
+    test_func(run_test_patches_par 4 ./test_patches)
+  else()
+    test_func(run_test_patches 1 ./test_patches)
+  endif()
+
   if (Omega_h_USE_Kokkos)
     osh_add_exe(bbox_reduce_test)
     osh_add_exe(initKokkosAndLib)
-    osh_add_exe(test_patches)
-    if(Omega_h_USE_MPI)
-      test_func(run_test_patches_par 4 ./test_patches)
-    else()
-      test_func(run_test_patches 1 ./test_patches)
-    endif()
   endif()
   list(APPEND TEST_EXES unit_math)
   test_basefunc(run_unit_math 1 ./unit_math)
@@ -852,7 +854,7 @@ if(Omega_h_USE_STK)
 endif()
 
 if(Omega_h_USE_Kokkos)
-  list(APPEND Omega_h_HEADERS Omega_h_memory.hpp)  
+  list(APPEND Omega_h_HEADERS Omega_h_memory.hpp)
   list(APPEND Omega_h_HEADERS Omega_h_pool_kokkos.hpp)
   list(APPEND Omega_h_HEADERS Omega_h_array_kokkos.hpp)
 else()

src/Omega_h_mesh.hpp

@@ -169,7 +169,6 @@ class Mesh {
       std::string const& name, Read<T> array);
   friend class ScopedChangeRCFieldsToMesh;
 
-  #if defined(OMEGA_H_USE_KOKKOS)
   /**
    * \brief form a patch of at least minPatchSize elements surrounding each mesh
    *        vertex
@@ -183,7 +182,6 @@ class Mesh {
    *         an empty graph upon failure
    */
   [[nodiscard]] Graph get_vtx_patches(Int minPatchSize, Int tgtDim = -1);
-  #endif
 
 
  private:
@@ -471,3 +469,4 @@ OMEGA_H_EXPL_INST_DECL(Real)
 }  // namespace Omega_h
 
 #endif
+

src/Omega_h_patches.cpp

@@ -7,8 +7,13 @@ using namespace Omega_h;
 
 #if defined(OMEGA_H_USE_KOKKOS)
 #include <Kokkos_NestedSort.hpp> //sort_team
+#endif
+
+#include <algorithm> //std::sort
 
 namespace {
+
+#if defined(OMEGA_H_USE_KOKKOS)
 [[nodiscard]] Graph adj_segment_sort(Graph& g) {
   using ExecSpace = Kokkos::DefaultExecutionSpace;
   using TeamPol = Kokkos::TeamPolicy<ExecSpace>;
@@ -25,6 +30,22 @@ namespace {
   Kokkos::parallel_for(TeamPol(g.nnodes(), Kokkos::AUTO()), segment_sort);
   return Graph(offsets,Write<LO>(elms));
 }
+#else
+[[nodiscard]] Graph adj_segment_sort(Graph& g) {
+  auto offsets = g.a2ab;
+  auto elms_r = HostRead(g.ab2b); //read only
+  HostWrite<LO> elms(elms_r.size(), "elms");
+  for (LO i = 0; i < elms.size(); ++i) {
+    elms[i] = elms_r[i];
+  }
+
+  for(LO i = 0; i < g.nnodes(); ++i) {
+    std::sort(elms.begin() + offsets[i], elms.begin() + offsets[i+1]);
+  }
+
+  return Graph(offsets, Read<LO>(elms));
+}
+#endif
 
 [[nodiscard]] Graph remove_duplicate_edges(Graph g) {
   auto offsets = g.a2ab;
@@ -131,4 +152,4 @@ namespace {
   }
   return Graph();
 }
-#endif
+

src/Omega_h_shared_alloc.hpp

@@ -133,6 +133,7 @@ struct SharedAlloc {
   }
   OMEGA_H_INLINE std::size_t size() const noexcept {
 #ifndef __CUDA_ARCH__
+    if (alloc == nullptr) return 0;
     if (!(reinterpret_cast<std::uintptr_t>(alloc) & IN_PARALLEL)) {
 #if defined(__GNUC__) && (__GNUC__ >= 7) && (!defined(__clang__))
 #pragma GCC diagnostic push