--- /dev/null
+/* -*- 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 non-commutative user-defined operations";
+*/
+
+/* 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;
+
+/* This implements a simple matrix-matrix multiply. This is an associative
+ but not commutative operation. The matrix size is set in matSize;
+ the number of matrices is the count argument. The matrix is stored
+ in C order, so that
+ c(i,j) is cin[j+i*matSize]
+ */
+#define MAXCOL 256
+static int matSize = 0; /* Must be < MAXCOL */
+static int max_offset = 0;
+void uop( void *, void *, int *, MPI_Datatype * );
+void uop( void *cinPtr, void *coutPtr, int *count, MPI_Datatype *dtype )
+{
+ const int *cin = (const int *)cinPtr;
+ int *cout = (int *)coutPtr;
+ int i, j, k, nmat;
+ int tempcol[MAXCOL];
+ int offset1, offset2;
+ int matsize2 = matSize*matSize;
+
+ for (nmat = 0; nmat < *count; nmat++) {
+ for (j=0; j<matSize; j++) {
+ for (i=0; i<matSize; i++) {
+ tempcol[i] = 0;
+ for (k=0; k<matSize; k++) {
+ /* col[i] += cin(i,k) * cout(k,j) */
+ offset1 = k+i*matSize;
+ offset2 = j+k*matSize;
+ assert(offset1 < max_offset);
+ assert(offset2 < max_offset);
+ tempcol[i] += cin[offset1] * cout[offset2];
+ }
+ }
+ for (i=0; i<matSize; i++) {
+ offset1 = j+i*matSize;
+ assert(offset1 < max_offset);
+ cout[offset1] = tempcol[i];
+ }
+ }
+ cin += matsize2;
+ cout += matsize2;
+ }
+}
+
+/* Initialize the integer matrix as a permutation of rank with rank+1.
+ If we call this matrix P_r, we know that product of P_0 P_1 ... P_{size-2}
+ is the the matrix representing the permutation that shifts left by one.
+ As the final matrix (in the size-1 position), we use the matrix that
+ shifts RIGHT by one
+*/
+static void initMat( MPI_Comm comm, int mat[] )
+{
+ int i, j, size, rank;
+ int offset;
+
+ MPI_Comm_rank( comm, &rank );
+ MPI_Comm_size( comm, &size );
+
+ for (i=0; i<size*size; i++) {
+ assert(i < max_offset);
+ mat[i] = 0;
+ }
+
+ if (rank < size-1) {
+ /* Create the permutation matrix that exchanges r with r+1 */
+ for (i=0; i<size; i++) {
+ if (i == rank) {
+ offset = ((i+1)%size) + i * size;
+ assert(offset < max_offset);
+ mat[offset] = 1;
+ }
+ else if (i == ((rank + 1)%size)) {
+ offset = ((i+size-1)%size) + i * size;
+ assert(offset < max_offset);
+ mat[offset] = 1;
+ }
+ else {
+ offset = i+i*size;
+ assert(offset < max_offset);
+ mat[offset] = 1;
+ }
+ }
+ }
+ else {
+ /* Create the permutation matrix that shifts right by one */
+ for (i=0; i<size; i++) {
+ for (j=0; j<size; j++) {
+ offset = j + i * size; /* location of c(i,j) */
+ mat[offset] = 0;
+ if ( ((j-i+size)%size) == 1 ) mat[offset] = 1;
+ }
+ }
+
+ }
+}
+
+/* Compare a matrix with the identity matrix */
+static int isIdentity( MPI_Comm comm, int mat[] )
+{
+ int i, j, size, rank, lerrs = 0;
+ int offset;
+
+ MPI_Comm_rank( comm, &rank );
+ MPI_Comm_size( comm, &size );
+
+ for (i=0; i<size; i++) {
+ for (j=0; j<size; j++) {
+ if (i == j) {
+ offset = j+i*size;
+ assert(offset < max_offset);
+ if (mat[offset] != 1) {
+ lerrs++;
+ if (errs + lerrs< 10) {
+ printf( "[%d] mat[%d,%d] = %d, expected 1 for comm %s\n",
+ rank, i,j, mat[offset], MTestGetIntracommName() );
+ }
+ }
+ }
+ else {
+ offset = j+i*size;
+ assert(offset < max_offset);
+ if (mat[offset] != 0) {
+ lerrs++;
+ if (errs + lerrs< 10) {
+ printf( "[%d] mat[%d,%d] = %d, expected 0 for comm %s\n",
+ rank, i,j, mat[offset], MTestGetIntracommName() );
+ }
+ }
+ }
+ }
+ }
+ return lerrs;
+}
+
+int main( int argc, char *argv[] )
+{
+ int size;
+ int minsize = 2, count;
+ MPI_Comm comm;
+ int *buf, *bufout;
+ MPI_Op op;
+ MPI_Datatype mattype;
+
+ MTest_Init( &argc, &argv );
+
+ MPI_Op_create( uop, 0, &op );
+
+ while (MTestGetIntracommGeneral( &comm, minsize, 1 )) {
+ if (comm == MPI_COMM_NULL) {
+ continue;
+ }
+ MPI_Comm_size( comm, &size );
+ matSize = size;
+
+ /* Only one matrix for now */
+ count = 1;
+
+ /* A single matrix, the size of the communicator */
+ MPI_Type_contiguous( size*size, MPI_INT, &mattype );
+ MPI_Type_commit( &mattype );
+
+ max_offset = count * size * size;
+ buf = (int *)malloc( max_offset * sizeof(int) );
+ if (!buf) {
+ MPI_Abort( MPI_COMM_WORLD, 1 );
+ }
+ bufout = (int *)malloc( max_offset * sizeof(int) );
+ if (!bufout) {
+ MPI_Abort( MPI_COMM_WORLD, 1 );
+ }
+
+ initMat( comm, buf );
+ MPI_Allreduce( buf, bufout, count, mattype, op, comm );
+ errs += isIdentity( comm, bufout );
+
+ /* Try the same test, but using MPI_IN_PLACE */
+ initMat( comm, bufout );
+ MPI_Allreduce( MPI_IN_PLACE, bufout, count, mattype, op, comm );
+ errs += isIdentity( comm, bufout );
+
+ free( buf );
+ free( bufout );
+
+ //MPI_Type_free( &mattype );
+ MTestFreeComm( &comm );
+ }
+
+ // MPI_Op_free( &op );
+
+ MTest_Finalize( errs );
+ MPI_Finalize();
+ return 0;
+}
