offload/test/offloading/non_contiguous_update.cpp

// RUN: %libomptarget-compile-generic && env LIBOMPTARGET_DEBUG=1 %libomptarget-run-generic 2>&1 | %fcheck-generic -allow-empty -check-prefix=DEBUG
// REQUIRES: libomptarget-debug

#include <cassert>
#include <cstdio>
#include <cstdlib>

// Data structure definitions copied from OpenMP RTL.
struct __tgt_target_non_contig {
  int64_t Offset;
  int64_t Count;
  int64_t Stride;
};

enum tgt_map_type { OMP_TGT_MAPTYPE_NON_CONTIG = 0x100000000000 };

// OpenMP RTL interfaces
#ifdef __cplusplus
extern "C" {
#endif
void __tgt_target_data_update(int64_t device_id, int32_t arg_num,
                              void **args_base, void **args, int64_t *arg_sizes,
                              int64_t *arg_types);
#ifdef __cplusplus
}
#endif

int main() {
  {
    // case 1
    // int32_t arr[3][4][5][6];
    // #pragma omp target update to(arr[0:2][1:3][1:2][:])
    // set up descriptor
    __tgt_target_non_contig non_contig[5] = {{0, 2, 4 * 5 * 6 * 4},
                                             {1 * 5 * 6 * 4, 3, 5 * 6 * 4},
                                             {6 * 4, 2, 6 * 4},
                                             {0, 6, 4},
                                             {0, 4, 1}};
    int64_t size = sizeof(non_contig) / sizeof(non_contig[0]),
            type = OMP_TGT_MAPTYPE_NON_CONTIG;

    void *base;
    void *begin = &non_contig;
    int64_t *sizes = &size;
    int64_t *types = &type;

    // The below diagram is the visualization of the non-contiguous transfer
    // after optimization. Note that each element represent the merged innermost
    // dimension (unit size = 24) since the stride * count of last dimension is
    // equal to the stride of second last dimension.
    //
    // OOOOO OOOOO OOOOO
    // OXXOO OXXOO OOOOO
    // OXXOO OXXOO OOOOO
    // OXXOO OXXOO OOOOO
    __tgt_target_data_update(/*device_id*/ -1, /*arg_num*/ 1, &base, &begin,
                             sizes, types);
    // DEBUG: offset 144 len 48
    // DEBUG: offset 264 len 48
    // DEBUG: offset 384 len 48
    // DEBUG: offset 624 len 48
    // DEBUG: offset 744 len 48
    // DEBUG: offset 864 len 48
  }

  {
    // case 2
    // int64_t darr[3][4][5];
    // #pragma omp target update to(darr[0:2:2][2:2][:2:2])
    // set up descriptor
    __tgt_target_non_contig non_contig[4] = {
        {0, 2, 2 * 4 * 5 * 8}, {2 * 5 * 8, 2, 5 * 8}, {0, 2, 2 * 8}, {0, 8, 1}};
    int64_t size = sizeof(non_contig) / sizeof(non_contig[0]),
            type = OMP_TGT_MAPTYPE_NON_CONTIG;

    void *base;
    void *begin = &non_contig;
    int64_t *sizes = &size;
    int64_t *types = &type;

    // The below diagram is the visualization of the non-contiguous transfer
    // after optimization. Note that each element represent the innermost
    // dimension (unit size = 8).
    //
    // OOOOO OOOOO OOOOO
    // OOOOO OOOOO OOOOO
    // XOXOO OOOOO XOXOO
    // XOXOO OOOOO XOXOO
    __tgt_target_data_update(/*device_id*/ -1, /*arg_num*/ 1, &base, &begin,
                             sizes, types);
    // DEBUG: offset 80 len 8
    // DEBUG: offset 96 len 8
    // DEBUG: offset 120 len 8
    // DEBUG: offset 136 len 8
    // DEBUG: offset 400 len 8
    // DEBUG: offset 416 len 8
    // DEBUG: offset 440 len 8
    // DEBUG: offset 456 len 8
  }

  {
    // case 3
    // int32_t darr[6][6];
    // #pragma omp target update to(darr[1:2:2][2:3])
    // set up descriptor
    __tgt_target_non_contig non_contig[3] = {{1 * 6 * 4 * 1, 2, 2 * 6 * 4 * 1},
                                             {2 * 4 * 1, 3, 1 * 4 * 1},
                                             {0, 4, 1}};
    int64_t size = sizeof(non_contig) / sizeof(non_contig[0]),
            type = OMP_TGT_MAPTYPE_NON_CONTIG;

    void *base;
    void *begin = &non_contig;
    int64_t *sizes = &size;
    int64_t *types = &type;

    // The below diagram is the visualization of the non-contiguous transfer
    // after optimization. Note that each element represent the merged innermost
    // dimension (unit size = 4).
    //
    // OOOOOO
    // OOXXXO
    // OOOOOO
    // OOXXXO
    // OOOOOO
    // OOOOOO
    __tgt_target_data_update(/*device_id*/ -1, /*arg_num*/ 1, &base, &begin,
                             sizes, types);
    // DEBUG: offset 32 len 12
    // DEBUG: offset 80 len 12
  }

  return 0;
}