/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */

/*

 *  (C) 2003 by Argonne National Laboratory.

 *      See COPYRIGHT in top-level directory.

 */

#include "mpi.h"

#include <stdio.h>

#include <stdlib.h>

#include "mpitest.h"

#include <assert.h>

/*

static char MTEST_Descrip[] = "Test MPI_Allreduce with count greater than the number of processes";

*/

/* We make the error count global so that we can easily control the output

   of error information (in particular, limiting it after the first 10

   errors */

int errs = 0;

int main(int argc, char *argv[])

{

    MPI_Comm comm;

    MPI_Datatype dtype;

    int count, *bufin, *bufout, size, i, minsize = 1;

    MTest_Init(&argc, &argv);

    while (MTestGetIntracommGeneral(&comm, minsize, 1)) {

        if (comm == MPI_COMM_NULL) {

            continue;

        }

        MPI_Comm_size(comm, &size);

        count = size * 2;

        bufin = (int *) malloc(count * sizeof(int));

        bufout = (int *) malloc(count * sizeof(int));

        if (!bufin || !bufout) {

            fprintf(stderr, "Unable to allocated space for buffers (%d)\n", count);

            MPI_Abort(MPI_COMM_WORLD, 1);

        }

        for (i = 0; i < count; i++) {

            bufin[i] = i;

            bufout[i] = -1;

        }

        dtype = MPI_INT;

        MPI_Allreduce(bufin, bufout, count, dtype, MPI_SUM, comm);

        /* Check output */

        for (i = 0; i < count; i++) {

            if (bufout[i] != i * size) {

                fprintf(stderr, "Expected bufout[%d] = %d but found %d\n", i, i * size, bufout[i]);

                errs++;

            }

        }

        free(bufin);

        free(bufout);

        MTestFreeComm(&comm);

    }

    MTest_Finalize(errs);

    return MTestReturnValue(errs);

}