Preparing for splitting of the two cases

src/field/DistributedField.cpp

@@ -261,15 +261,27 @@ namespace gmshfem::field
   void DistributedField< T_Scalar, T_Form >::_computeToSend(const std::optional<std::vector<int>>& neighborRanks)
   {
 #ifdef HAVE_MPI
+
     // What I have to send is what others have to read
 
+    // Create temporary MPI Type for the struct
+    const int nitems = 2;
+    int blocklengths[2] = {1, 1};
+    MPI_Datatype types[2] = {MPI_INT, MPI_UNSIGNED_LONG};
+    MPI_Datatype mpi_struct_type;
+    MPI_Aint offsets[2];
+    offsets[0] = 0;
+    offsets[1] = sizeof(int);
+    MPI_Type_create_struct(nitems, blocklengths, offsets, types, &mpi_struct_type);
+    MPI_Type_commit(&mpi_struct_type);
+
     // Send all owned interfaces and inner dofs that are read by someone else
     std::vector< DofGlobalIndex > local, global;
     local.reserve(_sharedDofs.size());
 
     unsigned commSize = gmshfem::common::GmshFem::getMPISize();
 
-    // Fill the local list
+    // Fill the local list of what I read
     for(dofs::Dof *dof : _toRead) {
       local.push_back({dof->numType(), dof->entity()});
     }
@@ -285,19 +297,7 @@ namespace gmshfem::field
       total_size += sizes[i];
     }
 
-    // Create temporary MPI Type for the struct
-    const int nitems = 2;
-    int blocklengths[2] = {1, 1};
-    MPI_Datatype types[2] = {MPI_INT, MPI_UNSIGNED_LONG};
-    MPI_Datatype mpi_struct_type;
-    MPI_Aint offsets[2];
-    //offsets[0] = offsetof(DofGlobalIndex, type);
-    //offsets[1] = offsetof(DofGlobalIndex, entity);
-    offsets[0] = 0;
-    offsets[1] = sizeof(int);
 
-    MPI_Type_create_struct(nitems, blocklengths, offsets, types, &mpi_struct_type);
-    MPI_Type_commit(&mpi_struct_type);
     // Synchronize the full array
     global.resize(total_size);
 
@@ -306,7 +306,6 @@ namespace gmshfem::field
                    MPI_COMM_WORLD);
 
     // Free the type
-    MPI_Type_free(&mpi_struct_type);
 
     _toSend.clear();
     // Global is the list of dof indices someone is reading
@@ -321,6 +320,9 @@ namespace gmshfem::field
           _toSend.insert(dof);
       }
     }
+
+    MPI_Type_free(&mpi_struct_type);
+
 #else
     throw common::Exception("MPI is not available");
 #endif