offload/test/offloading/parallel_target_teams_reduction_max.cpp

   1 // RUN: %libomptarget-compilexx-and-run-generic
   2 // RUN: %libomptarget-compileoptxx-and-run-generic
   3
   4 // FIXME: This is a bug in host offload, this should run fine.
   5 // REQUIRES: gpu
   6
   7 // This test validates that the OpenMP target reductions to find a maximum work
   8 // as indended for a few common data types.
   9
  10 #include <algorithm>
  11 #include <cassert>
  12 #include <limits>
  13 #include <vector>
  14
  15 template <class Tp> void test_max_idx_reduction() {
  16   const Tp length = 1000;
  17   const Tp nmaximas = 8;
  18   std::vector<float> a(length, 3.0f);
  19   const Tp step = length / nmaximas;
  20   for (Tp i = 0; i < nmaximas; i++) {
  21     a[i * step] += 1.0f;
  22   }
  23   for (Tp i = nmaximas; i > 0; i--) {
  24     Tp idx = 0;
  25     float *b = a.data();
  26 #pragma omp target teams distribute parallel for reduction(max : idx)          \
  27     map(always, to : b[0 : length])
  28     for (Tp j = 0; j < length - 1; j++) {
  29       if (b[j] > b[j + 1]) {
  30         idx = std::max(idx, j);
  31       }
  32     }
  33     assert(idx == (i - 1) * step &&
  34            "#pragma omp target teams distribute parallel for "
  35            "reduction(max:<identifier list>) does not work as intended.");
  36     a[idx] -= 1.0f;
  37   }
  38 }
  39
  40 template <class Tp> void test_max_val_reduction() {
  41   const int length = 1000;
  42   const int half = length / 2;
  43   std::vector<Tp> a(length, (Tp)3);
  44   a[half] += (Tp)1;
  45   Tp max_val = std::numeric_limits<Tp>::lowest();
  46   Tp *b = a.data();
  47 #pragma omp target teams distribute parallel for reduction(max : max_val)      \
  48     map(always, to : b[0 : length])
  49   for (int i = 0; i < length; i++) {
  50     max_val = std::max(max_val, b[i]);
  51   }
  52   assert(std::abs(((double)a[half + 1]) - ((double)max_val) + 1.0) < 1e-6 &&
  53          "#pragma omp target teams distribute parallel for "
  54          "reduction(max:<identifier list>) does not work as intended.");
  55 }
  56
  57 int main() {
  58   // Reducing over indices
  59   test_max_idx_reduction<int>();
  60   test_max_idx_reduction<unsigned int>();
  61   test_max_idx_reduction<long>();
  62
  63   // Reducing over values
  64   test_max_val_reduction<int>();
  65   test_max_val_reduction<unsigned int>();
  66   test_max_val_reduction<long>();
  67   test_max_val_reduction<float>();
  68   test_max_val_reduction<double>();
  69   return 0;
  70 }