static char help[] = "Tests VecSetValues() and VecSetValuesBlocked() on MPI vectors.\n\
Where at least a couple of mallocs will occur in the stash code.\n\n";

#include <petscvec.h>

int main(int argc, char **argv)
{
  PetscMPIInt size;
  PetscInt    i, j, r, n = 50, repeat = 1, bs;
  PetscScalar val, *vals, zero = 0.0;
  PetscBool   inv = PETSC_FALSE, subset = PETSC_FALSE, flg;
  Vec         x, y;

  PetscFunctionBeginUser;
  PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
  PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
  bs = size;

  PetscCall(PetscOptionsGetInt(NULL, NULL, "-repeat", &repeat, NULL));
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-subset", &subset, NULL));
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-invert", &inv, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-bs", &bs, NULL));
  PetscCall(VecCreate(PETSC_COMM_WORLD, &x));
  PetscCall(VecSetSizes(x, PETSC_DECIDE, n * bs));
  PetscCall(VecSetBlockSize(x, bs));
  PetscCall(VecSetFromOptions(x));
  PetscCall(VecDuplicate(x, &y));

  if (subset) PetscCall(VecSetOption(x, VEC_SUBSET_OFF_PROC_ENTRIES, PETSC_TRUE));

  for (r = 0; r < repeat; r++) {
    /* Assemble the full vector on the first and last iteration, otherwise don't set any values */
    for (i = 0; i < n * bs * (!r || !(repeat - 1 - r)); i++) {
      val = i * 1.0;
      PetscCall(VecSetValues(x, 1, &i, &val, INSERT_VALUES));
    }
    PetscCall(VecAssemblyBegin(x));
    PetscCall(VecAssemblyEnd(x));
    if (!r) PetscCall(VecCopy(x, y)); /* Save result of first assembly */
  }

  PetscCall(VecView(x, PETSC_VIEWER_STDOUT_WORLD));
  PetscCall(VecEqual(x, y, &flg));
  if (!flg) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Vectors from repeat assembly do not match."));

  /* Create a new vector because the old stash is a subset. */
  PetscCall(VecDestroy(&x));
  PetscCall(VecDuplicate(y, &x));
  if (subset) PetscCall(VecSetOption(x, VEC_SUBSET_OFF_PROC_ENTRIES, PETSC_TRUE));

  /* Now do the blocksetvalues */
  PetscCall(VecSet(x, zero));
  PetscCall(PetscMalloc1(bs, &vals));
  for (r = 0; r < repeat; r++) {
    PetscInt up = n * (!r || !(repeat - 1 - r));
    /* Assemble the full vector on the first and last iteration, otherwise don't set any values */
    for (i = 0; i < up; i++) {
      PetscInt ii = inv ? up - i - 1 : i;
      for (j = 0; j < bs; j++) vals[j] = (ii * bs + j) * 1.0;
      PetscCall(VecSetValuesBlocked(x, 1, &ii, vals, INSERT_VALUES));
    }
    PetscCall(VecAssemblyBegin(x));
    PetscCall(VecAssemblyEnd(x));
    if (!r) PetscCall(VecCopy(x, y)); /* Save result of first assembly */
  }

  PetscCall(VecView(x, PETSC_VIEWER_STDOUT_WORLD));
  PetscCall(VecEqual(x, y, &flg));
  if (!flg) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Vectors from repeat block assembly do not match."));

  PetscCall(VecDestroy(&x));
  PetscCall(VecDestroy(&y));
  PetscCall(PetscFree(vals));
  PetscCall(PetscFinalize());
  return 0;
}

/*TEST

   test:
      nsize: 3
      args: -n 126

   test:
      suffix: bts_test_inv_error
      nsize: 3
      args: -n 4 -invert -bs 2
      output_file: output/ex29_test_inv_error.out

   test:
      suffix: bts
      nsize: 3
      args: -n 126 -vec_assembly_legacy
      output_file: output/ex29_1.out

   test:
      suffix: bts_2
      nsize: 3
      args: -n 126 -vec_assembly_legacy -repeat 2
      output_file: output/ex29_1.out

   test:
      suffix: bts_2_subset
      nsize: 3
      args: -n 126 -vec_assembly_legacy -repeat 2 -subset
      output_file: output/ex29_1.out

   test:
      suffix: bts_2_subset_proper
      nsize: 3
      args: -n 126 -vec_assembly_legacy -repeat 5 -subset
      output_file: output/ex29_1.out

TEST*/
