1 // RUN: %clangxx_tsan -O1 %s %link_libcxx_tsan -o %t && %deflake %env_tsan_opts=atexit_sleep_ms=50 %run %t 2>&1 | FileCheck --check-prefix=CHECK-REPORT %s
2
3 #include <atomic>
4 #include <cassert>
5 #include <stdio.h>
6 #include <thread>
7
8 #define NUM_ORDS 16
9 #define NUM_THREADS NUM_ORDS * 2
10 struct node {
11 int val;
12 };
13 std::atomic<node *> _nodes[NUM_THREADS] = {};
14
f1(int i)15 void f1(int i) {
16 auto n = new node();
17 n->val = 42;
18 _nodes[i].store(n, std::memory_order_release);
19 }
20
21 template <int version>
f2(int i,std::memory_order mo,std::memory_order fmo)22 void f2(int i, std::memory_order mo, std::memory_order fmo) {
23 node *expected = nullptr;
24 while (expected == nullptr) {
25 _nodes[i].compare_exchange_weak(expected, nullptr, mo, fmo);
26 };
27
28 ++expected->val;
29 assert(expected->val == 43);
30 }
31
32 struct MemOrdSuccFail {
33 std::memory_order mo;
34 std::memory_order fmo;
35 };
36
37 MemOrdSuccFail OrdList[NUM_ORDS] = {
38 {std::memory_order_release, std::memory_order_relaxed},
39 {std::memory_order_release, std::memory_order_acquire},
40 {std::memory_order_release, std::memory_order_consume},
41 {std::memory_order_release, std::memory_order_seq_cst},
42
43 {std::memory_order_acq_rel, std::memory_order_relaxed},
44 {std::memory_order_acq_rel, std::memory_order_acquire},
45 {std::memory_order_acq_rel, std::memory_order_consume},
46 {std::memory_order_acq_rel, std::memory_order_seq_cst},
47
48 {std::memory_order_seq_cst, std::memory_order_relaxed},
49 {std::memory_order_seq_cst, std::memory_order_acquire},
50 {std::memory_order_seq_cst, std::memory_order_consume},
51 {std::memory_order_seq_cst, std::memory_order_seq_cst},
52
53 {std::memory_order_relaxed, std::memory_order_relaxed},
54 {std::memory_order_relaxed, std::memory_order_acquire},
55 {std::memory_order_relaxed, std::memory_order_consume},
56 {std::memory_order_relaxed, std::memory_order_seq_cst},
57 };
58
main()59 int main() {
60 std::thread threads[NUM_THREADS];
61 int ords = 0;
62
63 // Instantiate a new f2 for each MO so we can dedup reports and actually
64 // make sure relaxed FMO triggers a warning for every different MO.
65 for (unsigned t = 0; t < 8; t += 2) {
66 threads[t] = std::thread(f1, t);
67 threads[t + 1] = std::thread(f2<0>, t, OrdList[ords].mo, OrdList[ords].fmo);
68 threads[t].join();
69 threads[t + 1].join();
70 ords++;
71 }
72
73 for (unsigned t = 8; t < 16; t += 2) {
74 threads[t] = std::thread(f1, t);
75 threads[t + 1] = std::thread(f2<1>, t, OrdList[ords].mo, OrdList[ords].fmo);
76 threads[t].join();
77 threads[t + 1].join();
78 ords++;
79 }
80
81 for (unsigned t = 16; t < 24; t += 2) {
82 threads[t] = std::thread(f1, t);
83 threads[t + 1] = std::thread(f2<2>, t, OrdList[ords].mo, OrdList[ords].fmo);
84 threads[t].join();
85 threads[t + 1].join();
86 ords++;
87 }
88
89 for (unsigned t = 24; t < 32; t += 2) {
90 threads[t] = std::thread(f1, t);
91 threads[t + 1] = std::thread(f2<3>, t, OrdList[ords].mo, OrdList[ords].fmo);
92 threads[t].join();
93 threads[t + 1].join();
94 ords++;
95 }
96
97 fprintf(stderr, "DONE\n");
98 return 0;
99 }
100
101 // CHECK-REPORT: WARNING: ThreadSanitizer: data race
102 // CHECK-REPORT: WARNING: ThreadSanitizer: data race
103 // CHECK-REPORT: WARNING: ThreadSanitizer: data race
104 // CHECK-REPORT: WARNING: ThreadSanitizer: data race
105 // CHECK-REPORT: DONE
106 // CHECK-REPORT: ThreadSanitizer: reported 4 warnings
107