1// RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
2#include <pthread.h>
3#include <stdio.h>
4#include <unistd.h>
5
6const int kTestCount = 4;
7typedef long long T;
8T atomics[kTestCount * 2];
9
10void Test(int test, T *p, bool main_thread) {
11  volatile T sink;
12  if (test == 0) {
13    if (main_thread)
14      __atomic_fetch_add(p, 1, __ATOMIC_RELAXED);
15    else
16      __atomic_fetch_add(p, 1, __ATOMIC_RELAXED);
17  } else if (test == 1) {
18    if (main_thread)
19      __atomic_exchange_n(p, 1, __ATOMIC_ACQ_REL);
20    else
21      __atomic_exchange_n(p, 1, __ATOMIC_ACQ_REL);
22  } else if (test == 2) {
23    if (main_thread)
24      sink = __atomic_load_n(p, __ATOMIC_SEQ_CST);
25    else
26      __atomic_store_n(p, 1, __ATOMIC_SEQ_CST);
27  } else if (test == 3) {
28    if (main_thread)
29      sink = __atomic_load_n(p, __ATOMIC_SEQ_CST);
30    else
31      sink = *p;
32  }
33}
34
35void *Thread(void *p) {
36  for (int i = 0; i < kTestCount; i++) {
37    Test(i, &atomics[i], false);
38  }
39  sleep(2);
40  for (int i = 0; i < kTestCount; i++) {
41    fprintf(stderr, "Test %d reverse\n", i);
42    Test(i, &atomics[kTestCount + i], false);
43  }
44  return 0;
45}
46
47int main() {
48  pthread_t t;
49  pthread_create(&t, 0, Thread, 0);
50  sleep(1);
51  for (int i = 0; i < kTestCount; i++) {
52    fprintf(stderr, "Test %d\n", i);
53    Test(i, &atomics[i], true);
54  }
55  for (int i = 0; i < kTestCount; i++) {
56    Test(i, &atomics[kTestCount + i], true);
57  }
58  pthread_join(t, 0);
59}
60
61// CHECK-NOT: ThreadSanitizer: data race
62