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// RUN: %libomp-cxx-compile-and-run
#include <omp.h>
#include <algorithm>
#include <cassert>
#include <chrono>
#include <thread>
#include <vector>
// AIX runs out of resource in 32-bit if 4*omp_get_max_threads() is more
// than 64 threads with the default stack size.
#if defined(_AIX) && !__LP64__
#define MAX_THREADS 64
#endif
void dummy_root() {
// omp_get_max_threads() will do middle initialization
int nthreads = omp_get_max_threads();
std::this_thread::sleep_for(std::chrono::milliseconds(1000));
}
int main(int argc, char *argv[]) {
int N = std::min(std::max(std::max(32, 4 * omp_get_max_threads()),
4 * omp_get_num_procs()),
std::numeric_limits<int>::max());
#if defined(_AIX) && !__LP64__
if (N > MAX_THREADS)
N = MAX_THREADS;
#endif
std::vector<int> data(N);
// Create a new thread to initialize the OpenMP RTL. The new thread will not
// be taken as the "initial thread".
std::thread root(dummy_root);
#pragma omp parallel for num_threads(N)
for (unsigned i = 0; i < N; ++i) {
data[i] = i;
}
#pragma omp parallel for num_threads(N + 1)
for (unsigned i = 0; i < N; ++i) {
data[i] += i;
}
for (unsigned i = 0; i < N; ++i) {
assert(data[i] == 2 * i);
}
root.join();
return 0;
}
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