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/* { dg-do run } */
/* { dg-set-target-env-var OMP_CANCELLATION "true" } */
#include <stdlib.h>
#include <omp.h>
struct T { struct T *children[2]; int val; };
struct T *
search (struct T *tree, int val, int lvl)
{
if (tree == NULL || tree->val == val)
return tree;
struct T *ret = NULL;
int i;
for (i = 0; i < 2; i++)
#pragma omp task shared(ret) if(lvl < 10)
{
struct T *r = search (tree->children[i], val, lvl + 1);
if (r)
{
#pragma omp atomic write
ret = r;
#pragma omp cancel taskgroup
}
}
#pragma omp taskwait
return ret;
}
struct T *
searchp (struct T *tree, int val)
{
struct T *ret;
#pragma omp parallel shared(ret) firstprivate (tree, val)
#pragma omp single
#pragma omp taskgroup
ret = search (tree, val, 0);
return ret;
}
int
main ()
{
/* Must be power of two minus 1. */
int size = 0x7ffff;
struct T *trees = (struct T *) malloc (size * sizeof (struct T));
if (trees == NULL)
return 0;
int i, l = 1, b = 0;
for (i = 0; i < size; i++)
{
if (i == l)
{
b = l;
l = l * 2 + 1;
}
trees[i].val = i;
trees[i].children[0] = l == size ? NULL : &trees[l + (i - b) * 2];
trees[i].children[1] = l == size ? NULL : &trees[l + (i - b) * 2 + 1];
}
for (i = 0; i < 50; i++)
{
int v = random () & size;
if (searchp (&trees[0], v) != &trees[v])
abort ();
}
free (trees);
return 0;
}
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