openmp/runtime/test/teams/teams-atomic.c

   1 // Check that omp atomic is permitted and behaves when strictly nested within
   2 // omp teams.  This is an extension to OpenMP 5.2 and is enabled by default.
   3
   4 // RUN: %libomp-compile-and-run | FileCheck %s
   5 // GCC has really limited OpenMP 5.2 support yet.
   6 // UNSUPPORTED: gcc
   7
   8 #include <omp.h>
   9 #include <stdbool.h>
  10 #include <stdio.h>
  11 #include <string.h>
  12
  13 // High parallelism increases our chances of detecting a lack of atomicity.
  14 #define NUM_TEAMS_TRY 256
  15
  16 int main() {
  17   //      CHECK: update: num_teams=[[#NUM_TEAMS:]]{{$}}
  18   // CHECK-NEXT: update: x=[[#NUM_TEAMS]]{{$}}
  19   int x = 0;
  20   int numTeams;
  21   #pragma omp teams num_teams(NUM_TEAMS_TRY)
  22   {
  23     #pragma omp atomic update
  24     ++x;
  25     if (omp_get_team_num() == 0)
  26       numTeams = omp_get_num_teams();
  27   }
  28   printf("update: num_teams=%d\n", numTeams);
  29   printf("update: x=%d\n", x);
  30
  31   // CHECK-NEXT: capture: x=[[#NUM_TEAMS]]{{$}}
  32   // CHECK-NEXT: capture: xCapturedCount=[[#NUM_TEAMS]]{{$}}
  33   bool xCaptured[numTeams];
  34   memset(xCaptured, 0, sizeof xCaptured);
  35   x = 0;
  36   #pragma omp teams num_teams(NUM_TEAMS_TRY)
  37   {
  38     int v;
  39     #pragma omp atomic capture
  40     v = x++;
  41     xCaptured[v] = true;
  42   }
  43   printf("capture: x=%d\n", x);
  44   int xCapturedCount = 0;
  45   for (int i = 0; i < numTeams; ++i) {
  46     if (xCaptured[i])
  47       ++xCapturedCount;
  48   }
  49   printf("capture: xCapturedCount=%d\n", xCapturedCount);
  50   return 0;
  51 }