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#define printf(...)
kernel void
test_kernel (global int *output)
{
size_t flat_id = get_global_id (2) * get_global_size (1)
+ get_global_id (1) * get_global_size (0)
+ get_global_id (0);
size_t grid_size
= get_global_size (2) * get_global_size (1) * get_global_size (0);
printf ("a. flat_id %d lid %d\n", flat_id, get_local_id (0));
for (volatile int i = 0; i < 3; ++i)
{
output[flat_id] = flat_id * 1000 + i;
printf ("b. flat_id %d i %d lid %d\n", flat_id, i, get_local_id (0));
barrier (CLK_GLOBAL_MEM_FENCE);
printf ("c. flat_id %d i %d lid %d\n", flat_id, i, get_local_id (0));
int temp = output[flat_id + 1 == grid_size ? 0 : (flat_id + 1)];
barrier (CLK_GLOBAL_MEM_FENCE);
/* If the barrier was ignored, we are likely copying
a zero from the neighbour's slot or the previous
value (in case the iterations are executed in
lock step). */
output[flat_id] = temp;
printf ("d. flat_id %d i %d lid %d\n", flat_id, i, get_local_id (0));
}
}
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