starpu-max/examples/filters/shadow4d.c

/* StarPU --- Runtime system for heterogeneous multicore architectures.
 *
 * Copyright (C) 2010-2021  Université de Bordeaux, CNRS (LaBRI UMR 5800), Inria
 * Copyright (C) 2010       Mehdi Juhoor
 *
 * StarPU is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or (at
 * your option) any later version.
 *
 * StarPU is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * See the GNU Lesser General Public License in COPYING.LGPL for more details.
 */

/*
 * This examplifies the use of the 4D matrix shadow filters: a source "matrix" of
 * NX*NY*NZ*NT elements (plus SHADOW wrap-around elements) is partitioned into
 * matrices with some shadowing, and these are copied into a destination
 * "matrix2" of
 * NRPARTSX*NPARTSY*NPARTSZ*NPARTST*((NX/NPARTSX+2*SHADOWX)*(NY/NPARTSY+2*SHADOWY)*(NZ/NPARTSZ+2*SHADOWZ)*(NT/NPARTST+2*SHADOWT))
 * elements, partitioned in the traditionnal way, thus showing how shadowing
 * shows up.
 */

#include <starpu.h>

/* Shadow width */
#define SHADOWX 2
#define SHADOWY 2
#define SHADOWZ 1
#define SHADOWT 1
#define NX    6
#define NY    6
#define NZ    2
#define NT    2
#define PARTSX 2
#define PARTSY 2
#define PARTSZ 2
#define PARTST 2

#define FPRINTF(ofile, fmt, ...) do { if (!getenv("STARPU_SSILENT")) {fprintf(ofile, fmt, ## __VA_ARGS__); }} while(0)

void cpu_func(void *buffers[], void *cl_arg)
{
    (void)cl_arg;
        /* length of the shadowed source matrix */
        unsigned ldy = STARPU_TENSOR_GET_LDY(buffers[0]);
        unsigned ldz = STARPU_TENSOR_GET_LDZ(buffers[0]);
        unsigned ldt = STARPU_TENSOR_GET_LDT(buffers[0]);
        unsigned x = STARPU_TENSOR_GET_NX(buffers[0]);
        unsigned y = STARPU_TENSOR_GET_NY(buffers[0]);
        unsigned z = STARPU_TENSOR_GET_NZ(buffers[0]);
        unsigned t = STARPU_TENSOR_GET_NT(buffers[0]);
        /* local copy of the shadowed source matrix pointer */
        int *val = (int *)STARPU_TENSOR_GET_PTR(buffers[0]);

        /* length of the destination matrix */
        unsigned ldy2 = STARPU_TENSOR_GET_LDY(buffers[1]);
        unsigned ldz2 = STARPU_TENSOR_GET_LDZ(buffers[1]);
        unsigned ldt2 = STARPU_TENSOR_GET_LDT(buffers[1]);
        unsigned x2 = STARPU_TENSOR_GET_NX(buffers[1]);
        unsigned y2 = STARPU_TENSOR_GET_NY(buffers[1]);
        unsigned z2 = STARPU_TENSOR_GET_NZ(buffers[1]);
        unsigned t2 = STARPU_TENSOR_GET_NT(buffers[1]);
        /* local copy of the destination matrix pointer */
        int *val2 = (int *)STARPU_TENSOR_GET_PTR(buffers[1]);

    unsigned i, j, k, l;

    /* If things go right, sizes should match */
    STARPU_ASSERT(x == x2);
    STARPU_ASSERT(y == y2);
    STARPU_ASSERT(z == z2);
    STARPU_ASSERT(t == t2);
    for (l = 0; l < t; l++)
        for (k = 0; k < z; k++)
            for (j = 0; j < y; j++)
                for (i = 0; i < x; i++)
                    val2[l*ldt2+k*ldz2+j*ldy2+i] = val[l*ldt+k*ldz+j*ldy+i];
}

#ifdef STARPU_USE_CUDA
void cuda_func(void *buffers[], void *cl_arg)
{
    (void)cl_arg;
        /* length of the shadowed source matrix*/
        unsigned ldy = STARPU_TENSOR_GET_LDY(buffers[0]);
        unsigned ldz = STARPU_TENSOR_GET_LDZ(buffers[0]);
        unsigned ldt = STARPU_TENSOR_GET_LDT(buffers[0]);
        unsigned x = STARPU_TENSOR_GET_NX(buffers[0]);
        unsigned y = STARPU_TENSOR_GET_NY(buffers[0]);
        unsigned z = STARPU_TENSOR_GET_NZ(buffers[0]);
        unsigned t = STARPU_TENSOR_GET_NT(buffers[0]);
        /* local copy of the shadowed source matrix pointer */
        int *val = (int *)STARPU_TENSOR_GET_PTR(buffers[0]);

        /* length of the destination matrix */
        unsigned ldy2 = STARPU_TENSOR_GET_LDY(buffers[1]);
        unsigned ldz2 = STARPU_TENSOR_GET_LDZ(buffers[1]);
        unsigned ldt2 = STARPU_TENSOR_GET_LDT(buffers[1]);
        unsigned x2 = STARPU_TENSOR_GET_NX(buffers[1]);
        unsigned y2 = STARPU_TENSOR_GET_NY(buffers[1]);
        unsigned z2 = STARPU_TENSOR_GET_NZ(buffers[1]);
        unsigned t2 = STARPU_TENSOR_GET_NT(buffers[1]);
        /* local copy of the destination matrix pointer */
        int *val2 = (int *)STARPU_TENSOR_GET_PTR(buffers[1]);

    unsigned l;
    cudaError_t cures;

    /* If things go right, sizes should match */
    STARPU_ASSERT(x == x2);
    STARPU_ASSERT(y == y2);
    STARPU_ASSERT(z == z2);
    STARPU_ASSERT(t == t2);
    for (l = 0; l < t; l++)
    {
        for (k = 0; k < z; k++)
        {
            cures = cudaMemcpy2DAsync(val2+k*ldz2+l*ldt2, ldy2*sizeof(*val2), val+k*ldz+l*ldt, ldy*sizeof(*val),
                    x*sizeof(*val), y, cudaMemcpyDeviceToDevice, starpu_cuda_get_local_stream());
            STARPU_ASSERT(!cures);
        }
    }
        
}
#endif

int main(void)
{
    unsigned i, j, k, l, m, n, p, q;
    int matrix[NT + 2*SHADOWT][NZ + 2*SHADOWZ][NY + 2*SHADOWY][NX + 2*SHADOWX];
    int matrix2[NT + PARTST*2*SHADOWT][NZ + PARTSZ*2*SHADOWZ][NY + PARTSY*2*SHADOWY][NX + PARTSX*2*SHADOWX];
    starpu_data_handle_t handle, handle2;
    int ret;

    struct starpu_codelet cl =
    {
        .cpu_funcs = {cpu_func},
        .cpu_funcs_name = {"cpu_func"},
#ifdef STARPU_USE_CUDA
        .cuda_funcs = {cuda_func},
        .cuda_flags = {STARPU_CUDA_ASYNC},
#endif
        .nbuffers = 2,
        .modes = {STARPU_R, STARPU_W}
    };

    memset(matrix, -1, sizeof(matrix));
    for(l=1 ; l<=NT ; l++)
        for(k=1 ; k<=NZ ; k++)
            for(j=1 ; j<=NY ; j++)
                for(i=1 ; i<=NX ; i++)
                    matrix[SHADOWT+l-1][SHADOWZ+k-1][SHADOWY+j-1][SHADOWX+i-1] = i+j+k+l;

    /*copy cubes*/
    for (l = SHADOWT ; l<SHADOWT+NT ; l++)
        for (k = SHADOWZ ; k<SHADOWZ+NZ ; k++)
            for (j = SHADOWY ; j<SHADOWY+NY ; j++)
                for(i=0 ; i<SHADOWX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l][k][j][i+NX];
                    matrix[l][k][j][SHADOWX+NX+i] = matrix[l][k][j][SHADOWX+i];
                }
    for (l = SHADOWT ; l<SHADOWT+NT ; l++)
        for(k=SHADOWZ ; k<SHADOWZ+NZ ; k++)
            for(j=0 ; j<SHADOWY ; j++)
                for(i=SHADOWX ; i<SHADOWX+NX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l][k][j+NY][i];
                    matrix[l][k][SHADOWY+NY+j][i] = matrix[l][k][SHADOWY+j][i];
                }
    for (l = SHADOWT ; l<SHADOWT+NT ; l++)
        for(k=0 ; k<SHADOWZ ; k++)
            for(j=SHADOWY ; j<SHADOWY+NY ; j++)
                for(i=SHADOWX ; i<SHADOWX+NX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l][k+NZ][j][i];
                    matrix[l][SHADOWZ+NZ+k][j][i] = matrix[l][SHADOWZ+k][j][i];
                }
    for (l = 0 ; l<SHADOWT ; l++)
        for(k=SHADOWZ ; k<SHADOWZ+NZ ; k++)
            for(j=SHADOWY ; j<SHADOWY+NY ; j++)
                for(i=SHADOWX ; i<SHADOWX+NX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l+NT][k][j][i];
                    matrix[SHADOWT+NT+l][k][j][i] = matrix[SHADOWT+l][k][j][i];
                }

    /*copy planes*/
    for (l = SHADOWT ; l<SHADOWT+NT ; l++)
        for (k = SHADOWZ ; k<SHADOWZ+NZ ; k++)
            for(j=0 ; j<SHADOWY ; j++)
                for(i=0 ; i<SHADOWX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l][k][j+NY][i+NX];
                    matrix[l][k][j][SHADOWX+NX+i] = matrix[l][k][j+NY][SHADOWX+i];
                    matrix[l][k][SHADOWY+NY+j][i] = matrix[l][k][SHADOWY+j][i+NX];
                    matrix[l][k][SHADOWY+NY+j][SHADOWX+NX+i] = matrix[l][k][SHADOWY+j][SHADOWX+i];
                }

    for (l = SHADOWT ; l<SHADOWT+NT ; l++)
        for (k=0 ; k<SHADOWZ ; k++)
            for(j = SHADOWY ; j<SHADOWY+NY ; j++)
                for(i=0 ; i<SHADOWX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l][k+NZ][j][i+NX];
                    matrix[l][k][j][SHADOWX+NX+i] = matrix[l][k+NZ][j][SHADOWX+i];
                    matrix[l][SHADOWZ+NZ+k][j][i] = matrix[l][SHADOWZ+k][j][i+NX];
                    matrix[l][SHADOWZ+NZ+k][j][SHADOWX+NX+i] = matrix[l][SHADOWZ+k][j][SHADOWX+i];
                }

    for (l = SHADOWT ; l<SHADOWT+NT ; l++)
        for (k=0 ; k<SHADOWZ ; k++)
            for(j=0 ; j<SHADOWY ; j++)
                for(i=SHADOWX ; i<SHADOWX+NX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l][k+NZ][j+NY][i];
                    matrix[l][k][SHADOWY+NY+j][i] = matrix[l][k+NZ][SHADOWY+j][i];
                    matrix[l][SHADOWZ+NZ+k][j][i] = matrix[l][SHADOWZ+k][j+NY][i];
                    matrix[l][SHADOWZ+NZ+k][SHADOWY+NY+j][i] = matrix[l][SHADOWZ+k][SHADOWY+j][i];
                }

    for (l=0 ; l<SHADOWT ; l++)
        for (k = SHADOWZ ; k<SHADOWZ+NZ ; k++)
            for(j = SHADOWY ; j<SHADOWY+NY ; j++)
                for(i=0 ; i<SHADOWX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l+NT][k][j][i+NX];
                    matrix[l][k][j][SHADOWX+NX+i] = matrix[l+NT][k][j][SHADOWX+i];
                    matrix[SHADOWT+NT+l][k][j][i] = matrix[SHADOWT+l][k][j][i+NX];
                    matrix[SHADOWT+NT+l][k][j][SHADOWX+NX+i] = matrix[SHADOWT+l][k][j][SHADOWX+i];
                }

    for (l=0 ; l<SHADOWT ; l++)
        for (k = SHADOWZ ; k<SHADOWZ+NZ ; k++)
            for(j=0 ; j<SHADOWY ; j++)
                for(i=SHADOWX ; i<SHADOWX+NX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l+NT][k][j+NY][i];
                    matrix[l][k][SHADOWY+NY+j][i] = matrix[l+NT][k][SHADOWY+j][i];
                    matrix[SHADOWT+NT+l][k][j][i] = matrix[SHADOWT+l][k][j+NY][i];
                    matrix[SHADOWT+NT+l][k][SHADOWY+NY+j][i] = matrix[SHADOWT+l][k][SHADOWY+j][i];
                }

    for (l=0 ; l<SHADOWT ; l++)
        for(k=0 ; k<SHADOWZ ; k++)
            for (j = SHADOWY ; j<SHADOWY+NY ; j++)
                for(i=SHADOWX ; i<SHADOWX+NX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l+NT][k+NZ][j][i];
                    matrix[l][SHADOWZ+NZ+k][j][i] = matrix[l+NT][SHADOWZ+k][j][i];
                    matrix[SHADOWT+NT+l][k][j][i] = matrix[SHADOWT+l][k+NZ][j][i];
                    matrix[SHADOWT+NT+l][SHADOWZ+NZ+k][j][i] = matrix[SHADOWT+l][SHADOWZ+k][j][i];
                }

    /* Copy borders */
    for (l = SHADOWT ; l<SHADOWT+NT ; l++)
        for (k=0 ; k<SHADOWZ ; k++)
            for(j=0 ; j<SHADOWY ; j++)
                for(i=0 ; i<SHADOWX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l][k+NZ][j+NY][i+NX];
                    matrix[l][k][j][SHADOWX+NX+i] = matrix[l][k+NZ][j+NY][SHADOWX+i];
                    matrix[l][k][SHADOWY+NY+j][i] = matrix[l][k+NZ][SHADOWY+j][i+NX];
                    matrix[l][k][SHADOWY+NY+j][SHADOWX+NX+i] = matrix[l][k+NZ][SHADOWY+j][SHADOWX+i];
                    matrix[l][SHADOWZ+NZ+k][j][i] = matrix[l][SHADOWZ+k][j+NY][i+NX];
                    matrix[l][SHADOWZ+NZ+k][j][SHADOWX+NX+i] = matrix[l][SHADOWZ+k][j+NY][SHADOWX+i];
                    matrix[l][SHADOWZ+NZ+k][SHADOWY+NY+j][i] = matrix[l][SHADOWZ+k][SHADOWY+j][i+NX];
                    matrix[l][SHADOWZ+NZ+k][SHADOWY+NY+j][SHADOWX+NX+i] = matrix[l][SHADOWZ+k][SHADOWY+j][SHADOWX+i];
                }
    for (l=0 ; l<SHADOWT ; l++)
        for (k = SHADOWZ ; k<SHADOWZ+NZ ; k++)
            for(j=0 ; j<SHADOWY ; j++)
                for(i=0 ; i<SHADOWX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l+NT][k][j+NY][i+NX];
                    matrix[l][k][j][SHADOWX+NX+i] = matrix[l+NT][k][j+NY][SHADOWX+i];
                    matrix[l][k][SHADOWY+NY+j][i] = matrix[l+NT][k][SHADOWY+j][i+NX];
                    matrix[SHADOWT+NT+l][k][j][i] = matrix[SHADOWT+l][k][j+NY][i+NX];
                    matrix[l][k][SHADOWY+NY+j][SHADOWX+NX+i] = matrix[l+NT][k][SHADOWY+j][SHADOWX+i];
                    matrix[SHADOWT+NT+l][k][j][SHADOWX+NX+i] = matrix[SHADOWT+l][k][j+NY][SHADOWX+i];
                    matrix[SHADOWT+NT+l][k][SHADOWY+NY+j][i] = matrix[SHADOWT+l][k][SHADOWY+j][i+NX];
                    matrix[SHADOWT+NT+l][k][SHADOWY+NY+j][SHADOWX+NX+i] = matrix[SHADOWT+l][k][SHADOWY+j][SHADOWX+i];
                }
    for (l=0 ; l<SHADOWT ; l++)
        for(k=0 ; k<SHADOWZ ; k++)
            for (j = SHADOWY ; j<SHADOWY+NY ; j++)
                for(i=0 ; i<SHADOWX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l+NT][k+NZ][j][i+NX];
                    matrix[l][k][j][SHADOWX+NX+i] = matrix[l+NT][k+NZ][j][SHADOWX+i];
                    matrix[l][SHADOWZ+NZ+k][j][i] = matrix[l+NT][SHADOWZ+k][j][i+NX];
                    matrix[SHADOWT+NT+l][k][j][i] = matrix[SHADOWT+l][k+NZ][j][i+NX];
                    matrix[l][SHADOWZ+NZ+k][j][SHADOWX+NX+i] = matrix[l+NT][SHADOWZ+k][j][SHADOWX+i];
                    matrix[SHADOWT+NT+l][k][j][SHADOWX+NX+i] = matrix[SHADOWT+l][k+NZ][j][SHADOWX+i];
                    matrix[SHADOWT+NT+l][SHADOWZ+NZ+k][j][i] = matrix[SHADOWT+l][SHADOWZ+k][j][i+NX];
                    matrix[SHADOWT+NT+l][SHADOWZ+NZ+k][j][SHADOWX+NX+i] = matrix[SHADOWT+l][SHADOWZ+k][j][SHADOWX+i];
                }
    for (l=0 ; l<SHADOWT ; l++)
        for(k=0 ; k<SHADOWZ ; k++)
            for(j=0 ; j<SHADOWY ; j++)
                for(i=SHADOWX ; i<SHADOWX+NX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l+NT][k+NZ][j+NY][i];
                    matrix[l][k][SHADOWY+NY+j][i] = matrix[l+NT][k+NZ][SHADOWY+j][i];
                    matrix[l][SHADOWZ+NZ+k][j][i] = matrix[l+NT][SHADOWZ+k][j+NY][i];
                    matrix[SHADOWT+NT+l][k][j][i] = matrix[SHADOWT+l][k+NZ][j+NY][i];
                    matrix[l][SHADOWZ+NZ+k][SHADOWY+NY+j][i] = matrix[l+NT][SHADOWZ+k][SHADOWY+j][i];
                    matrix[SHADOWT+NT+l][k][SHADOWY+NY+j][i] = matrix[SHADOWT+l][k+NZ][SHADOWY+j][i];
                    matrix[SHADOWT+NT+l][SHADOWZ+NZ+k][j][i] = matrix[SHADOWT+l][SHADOWZ+k][j+NY][i];
                    matrix[SHADOWT+NT+l][SHADOWZ+NZ+k][SHADOWY+NY+j][i] = matrix[SHADOWT+l][SHADOWZ+k][SHADOWY+j][i];
                }

    /* Copy corners */
    for(l=0 ; l<SHADOWT ; l++)
        for(k=0 ; k<SHADOWZ ; k++)
            for(j=0 ; j<SHADOWY ; j++)
                for(i=0 ; i<SHADOWX ; i++)
                {
                    matrix[l][k][j][i] = matrix[l+NT][k+NZ][j+NY][i+NX];
                    matrix[l][k][j][SHADOWX+NX+i] = matrix[l+NT][k+NZ][j+NY][SHADOWX+i];
                    matrix[l][k][SHADOWY+NY+j][i] = matrix[l+NT][k+NZ][SHADOWY+j][i+NX];
                    matrix[l][k][SHADOWY+NY+j][SHADOWX+NX+i] = matrix[l+NT][k+NZ][SHADOWY+j][SHADOWX+i];
                    matrix[l][SHADOWZ+NZ+k][j][i] = matrix[l+NT][SHADOWZ+k][j+NY][i+NX];
                    matrix[l][SHADOWZ+NZ+k][j][SHADOWX+NX+i] = matrix[l+NT][SHADOWZ+k][j+NY][SHADOWX+i];
                    matrix[l][SHADOWZ+NZ+k][SHADOWY+NY+j][i] = matrix[l+NT][SHADOWZ+k][SHADOWY+j][i+NX];
                    matrix[l][SHADOWZ+NZ+k][SHADOWY+NY+j][SHADOWX+NX+i] = matrix[l+NT][SHADOWZ+k][SHADOWY+j][SHADOWX+i];
                    matrix[SHADOWT+NT+l][k][j][i] = matrix[SHADOWT+l][k+NZ][j+NY][i+NX];
                    matrix[SHADOWT+NT+l][k][j][SHADOWX+NX+i] = matrix[SHADOWT+l][k+NZ][j+NY][SHADOWX+i];
                    matrix[SHADOWT+NT+l][k][SHADOWY+NY+j][i] = matrix[SHADOWT+l][k+NZ][SHADOWY+j][i+NX];
                    matrix[SHADOWT+NT+l][SHADOWZ+NZ+k][j][i] = matrix[SHADOWT+l][SHADOWZ+k][j+NY][i+NX];
                    matrix[SHADOWT+NT+l][k][SHADOWY+NY+j][SHADOWX+NX+i] = matrix[SHADOWT+l][k+NZ][SHADOWY+j][SHADOWX+i];
                    matrix[SHADOWT+NT+l][SHADOWZ+NZ+k][j][SHADOWX+NX+i] = matrix[SHADOWT+l][SHADOWZ+k][j+NY][SHADOWX+i];
                    matrix[SHADOWT+NT+l][SHADOWZ+NZ+k][SHADOWY+NY+j][i] = matrix[SHADOWT+l][SHADOWZ+k][SHADOWY+j][i+NX];
                    matrix[SHADOWT+NT+l][SHADOWZ+NZ+k][SHADOWY+NY+j][SHADOWX+NX+i] = matrix[SHADOWT+l][SHADOWZ+k][SHADOWY+j][SHADOWX+i];
                }

    FPRINTF(stderr,"IN  Matrix:\n");
    for(l=0 ; l<NT + 2*SHADOWT ; l++)
    {
        for(k=0 ; k<NZ + 2*SHADOWZ ; k++)
        {
            for(j=0 ; j<NY + 2*SHADOWY ; j++)
            {
                for(i=0 ; i<NX + 2*SHADOWX ; i++)
                    FPRINTF(stderr, "%5d ", matrix[l][k][j][i]);
                FPRINTF(stderr,"\n");
            }
            FPRINTF(stderr,"\n\n");
        }
        FPRINTF(stderr,"\n\n");
    }
    FPRINTF(stderr,"\n");

    ret = starpu_init(NULL);
    if (ret == -ENODEV)
        exit(77);
    STARPU_CHECK_RETURN_VALUE(ret, "starpu_init");

    /* Declare source matrix to StarPU */
    starpu_tensor_data_register(&handle, STARPU_MAIN_RAM, (uintptr_t)matrix,
            NX + 2*SHADOWX, (NX + 2*SHADOWX) * (NY + 2*SHADOWY), (NX + 2*SHADOWX) * (NY + 2*SHADOWY) * (NZ + 2*SHADOWZ),
            NX + 2*SHADOWX, NY + 2*SHADOWY, NZ + 2*SHADOWZ, NT + 2*SHADOWT,
            sizeof(matrix[0][0][0][0]));

    /* Declare destination matrix to StarPU */
    starpu_tensor_data_register(&handle2, STARPU_MAIN_RAM, (uintptr_t)matrix2,
            NX + PARTSX*2*SHADOWX, (NX + PARTSX*2*SHADOWX) * (NY + PARTSY*2*SHADOWY), (NX + PARTSX*2*SHADOWX) * (NY + PARTSY*2*SHADOWY) * (NZ + PARTSZ*2*SHADOWZ),
            NX + PARTSX*2*SHADOWX, NY + PARTSY*2*SHADOWY, NZ + PARTSZ*2*SHADOWZ, NT + PARTST*2*SHADOWT,
            sizeof(matrix2[0][0][0][0]));

    /* Partition the source matrix in PARTST*PARTSZ*PARTSY*PARTSX sub-matrices with shadows */
    /* NOTE: the resulting handles should only be used in read-only mode,
     * as StarPU will not know how the overlapping parts would have to be
     * combined. */
    struct starpu_data_filter ft =
    {
        .filter_func = starpu_tensor_filter_time_block_shadow,
        .nchildren = PARTST,
        .filter_arg_ptr = (void*)(uintptr_t) SHADOWT /* Shadow width */
    };
    struct starpu_data_filter fz =
    {
        .filter_func = starpu_tensor_filter_depth_block_shadow,
        .nchildren = PARTSZ,
        .filter_arg_ptr = (void*)(uintptr_t) SHADOWZ /* Shadow width */
    };
    struct starpu_data_filter fy =
    {
        .filter_func = starpu_tensor_filter_vertical_block_shadow,
        .nchildren = PARTSY,
        .filter_arg_ptr = (void*)(uintptr_t) SHADOWY /* Shadow width */
    };
    struct starpu_data_filter fx =
    {
        .filter_func = starpu_tensor_filter_block_shadow,
        .nchildren = PARTSX,
        .filter_arg_ptr = (void*)(uintptr_t) SHADOWX /* Shadow width */
    };
    starpu_data_map_filters(handle, 4, &ft, &fz, &fy, &fx);

    /* Partition the destination matrix in PARTST*PARTSZ*PARTSY*PARTSX sub-matrices */
    struct starpu_data_filter ft2 =
    {
        .filter_func = starpu_tensor_filter_time_block,
        .nchildren = PARTST,
    };
    struct starpu_data_filter fz2 =
    {
        .filter_func = starpu_tensor_filter_depth_block,
        .nchildren = PARTSZ,
    };
    struct starpu_data_filter fy2 =
    {
        .filter_func = starpu_tensor_filter_vertical_block,
        .nchildren = PARTSY,
    };
    struct starpu_data_filter fx2 =
    {
        .filter_func = starpu_tensor_filter_block,
        .nchildren = PARTSX,
    };
    starpu_data_map_filters(handle2, 4, &ft2, &fz2, &fy2, &fx2);


    /* Submit a task on each sub-matrix */
    for (l=0; l<PARTST; l++)
    {
        for (k=0; k<PARTSZ; k++)
        {
            for (j=0; j<PARTSY; j++)
            {
                for (i=0; i<PARTSX; i++)
                {
                    starpu_data_handle_t sub_handle = starpu_data_get_sub_data(handle, 4, l, k, j, i);
                    starpu_data_handle_t sub_handle2 = starpu_data_get_sub_data(handle2, 4, l, k, j, i);
                    struct starpu_task *task = starpu_task_create();

                    task->handles[0] = sub_handle;
                    task->handles[1] = sub_handle2;
                    task->cl = &cl;
                    task->synchronous = 1;

                    ret = starpu_task_submit(task);
                    if (ret == -ENODEV) goto enodev;
                    STARPU_CHECK_RETURN_VALUE(ret, "starpu_task_submit");
                }
            }
        }
    }

    starpu_data_unpartition(handle, STARPU_MAIN_RAM);
    starpu_data_unpartition(handle2, STARPU_MAIN_RAM);
    starpu_data_unregister(handle);
    starpu_data_unregister(handle2);
    starpu_shutdown();

    FPRINTF(stderr,"OUT Matrix:\n");
    for(l=0 ; l<NT + PARTST*2*SHADOWT ; l++)
    {
        for(k=0 ; k<NZ + PARTSZ*2*SHADOWZ ; k++)
        {
            for(j=0 ; j<NY + PARTSY*2*SHADOWY ; j++)
            {
                for(i=0 ; i<NX + PARTSX*2*SHADOWX ; i++)
                {
                    FPRINTF(stderr, "%5d ", matrix2[l][k][j][i]);
                }
                FPRINTF(stderr,"\n");
            }
            FPRINTF(stderr,"\n\n");
        }
        FPRINTF(stderr,"\n\n");
    }
    FPRINTF(stderr,"\n");
    for(l=0 ; l<PARTST ; l++)
        for(k=0 ; k<PARTSZ ; k++)
            for(j=0 ; j<PARTSY ; j++)
                for(i=0 ; i<PARTSX ; i++)
                    for (q=0 ; q<NT/PARTST + 2*SHADOWT ; q++)
                        for (p=0 ; p<NZ/PARTSZ + 2*SHADOWZ ; p++)
                            for (n=0 ; n<NY/PARTSY + 2*SHADOWY ; n++)
                                for (m=0 ; m<NX/PARTSX + 2*SHADOWX ; m++)
                                    STARPU_ASSERT(matrix2[l*(NT/PARTST+2*SHADOWT)+q][k*(NZ/PARTSZ+2*SHADOWZ)+p][j*(NY/PARTSY+2*SHADOWY)+n][i*(NX/PARTSX+2*SHADOWX)+m] ==
                                            matrix[l*(NT/PARTST)+q][k*(NZ/PARTSZ)+p][j*(NY/PARTSY)+n][i*(NX/PARTSX)+m]);

    return 0;

enodev:
    FPRINTF(stderr, "WARNING: No one can execute this task\n");
    starpu_shutdown();
    return 77;
}