openmp/runtime/test/worksharing/for/omp_for_bigbounds.c

   1 // RUN: %libomp-compile -DMY_SCHEDULE=static && %libomp-run
   2 // RUN: %libomp-compile -DMY_SCHEDULE=dynamic && %libomp-run
   3 // RUN: %libomp-compile -DMY_SCHEDULE=guided && %libomp-run
   4
   5 // Only works with Intel Compiler since at least version 15.0 and clang since
   6 // version 11.
   7
   8 // XFAIL: gcc, clang-3, clang-4, clang-5, clang-6, clang-7, clang-8, clang-9, clang-10
   9
  10 // icc 21 seems to have an issue with the loop boundaries and runs very long
  11 // UNSUPPORTED: icc-21
  12
  13 /*
  14  * Test that large bounds are handled properly and calculations of
  15  * loop iterations don't accidentally overflow
  16  */
  17 #include <stdio.h>
  18 #include <omp.h>
  19 #include <stdlib.h>
  20 #include <limits.h>
  21 #include "omp_testsuite.h"
  22
  23 #define INCR      50000000
  24 #define MY_MAX  2000000000
  25 #define MY_MIN -2000000000
  26 #ifndef MY_SCHEDULE
  27 # define MY_SCHEDULE static
  28 #endif
  29
  30 int a, b, a_known_value, b_known_value;
  31
  32 int test_omp_for_bigbounds()
  33 {
  34   a = 0;
  35   b = 0;
  36   #pragma omp parallel
  37   {
  38     int i;
  39     #pragma omp for schedule(MY_SCHEDULE) reduction(+:a)
  40     for (i = INT_MIN; i < MY_MAX; i+=INCR) {
  41         a++;
  42     }
  43     #pragma omp for schedule(MY_SCHEDULE) reduction(+:b)
  44     for (i = INT_MAX; i >= MY_MIN; i-=INCR) {
  45         b++;
  46     }
  47   }
  48   printf("a = %d (should be %d), b = %d (should be %d)\n", a, a_known_value, b, b_known_value);
  49   return (a == a_known_value && b == b_known_value);
  50 }
  51
  52 int main()
  53 {
  54   int i;
  55   int num_failed=0;
  56
  57   a_known_value = 0;
  58   for (i = INT_MIN; i < MY_MAX; i+=INCR) {
  59       a_known_value++;
  60   }
  61
  62   b_known_value = 0;
  63   for (i = INT_MAX; i >= MY_MIN; i-=INCR) {
  64       b_known_value++;
  65   }
  66
  67   for(i = 0; i < REPETITIONS; i++) {
  68     if(!test_omp_for_bigbounds()) {
  69       num_failed++;
  70     }
  71   }
  72   return num_failed;
  73 }