1: static const char help[] = "Test PetscSF with derived data types created with MPI large count\n\n";

  3: #include <petscsf.h>

  5: int main(int argc, char **argv)
  6: {
  7:   PetscSF        sf;
  8:   PetscInt       i, nroots, nleaves;
  9:   const PetscInt m = 4, n = 64;
 10:   PetscSFNode   *iremote = NULL;
 11:   PetscMPIInt    rank, size;
 12:   int           *rootdata = NULL, *leafdata = NULL;
 13:   MPI_Datatype   newtype;

 15:   PetscFunctionBeginUser;
 16:   PetscCall(PetscInitialize(&argc, &argv, NULL, help));
 17:   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
 18:   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
 19:   PetscCheck(size == 2, PETSC_COMM_WORLD, PETSC_ERR_WRONG_MPI_SIZE, "The test can only run with two MPI ranks");

 21:   PetscCall(PetscSFCreate(PETSC_COMM_WORLD, &sf));
 22:   PetscCall(PetscSFSetFromOptions(sf));

 24:   if (rank == 0) {
 25:     nroots  = n;
 26:     nleaves = 0;
 27:   } else {
 28:     nroots  = 0;
 29:     nleaves = n;
 30:     PetscCall(PetscMalloc1(nleaves, &iremote));
 31:     for (i = 0; i < nleaves; i++) {
 32:       iremote[i].rank  = 0;
 33:       iremote[i].index = i;
 34:     }
 35:   }
 36:   PetscCall(PetscSFSetGraph(sf, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));

 38:   PetscCall(PetscCalloc2(nroots * m, &rootdata, nleaves * m, &leafdata)); // allocate fat nodes to apply a derived data type of m MPI_INTs

 40:   if (rank == 0) rootdata[nroots * m - 1] = 123; // set the last integer in rootdata and then check on leaves

 42: #if PetscDefined(HAVE_MPI_LARGE_COUNT)
 43:   PetscCallMPI(MPI_Type_contiguous_c(m, MPI_INT, &newtype));
 44: #else
 45:   PetscCallMPI(MPI_Type_contiguous(m, MPI_INT, &newtype));
 46: #endif

 48:   PetscCallMPI(MPI_Type_commit(&newtype));

 50:   PetscCall(PetscSFBcastBegin(sf, newtype, rootdata, leafdata, MPI_REPLACE)); //  bcast rootdata to leafdata
 51:   PetscCall(PetscSFBcastEnd(sf, newtype, rootdata, leafdata, MPI_REPLACE));

 53:   if (rank == 1) PetscCheck(leafdata[nleaves * m - 1] == 123, PETSC_COMM_SELF, PETSC_ERR_PLIB, "SF: wrong results");

 55:   PetscCallMPI(MPI_Type_free(&newtype));
 56:   PetscCall(PetscFree2(rootdata, leafdata));
 57:   PetscCall(PetscSFDestroy(&sf));
 58:   PetscCall(PetscFinalize());
 59:   return 0;
 60: }

 62: /**TEST
 63:    test:
 64:      nsize: 2
 65:      output_file: output/empty.out
 66:      args: -sf_type {{basic neighbor}}

 68: TEST**/