xref: /llvm-project/libcxx/test/std/atomics/atomics.flag/clear.pass.cpp (revision 92832e4889ae6038cc8b3e6e449af2a9b9374ab4)
1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // <atomic>
10 
11 // struct atomic_flag
12 
13 // void clear(memory_order = memory_order_seq_cst);
14 // void clear(memory_order = memory_order_seq_cst) volatile;
15 
16 #include <atomic>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 
main(int,char **)21 int main(int, char**)
22 {
23     {
24         std::atomic_flag f; // uninitialized
25         f.clear();
26         assert(f.test_and_set() == 0);
27         f.clear();
28         assert(f.test_and_set() == 0);
29     }
30     {
31         std::atomic_flag f;
32         f.clear(std::memory_order_relaxed);
33         assert(f.test_and_set() == 0);
34         f.clear(std::memory_order_relaxed);
35         assert(f.test_and_set() == 0);
36     }
37     {
38         std::atomic_flag f;
39         f.clear(std::memory_order_release);
40         assert(f.test_and_set() == 0);
41         f.clear(std::memory_order_release);
42         assert(f.test_and_set() == 0);
43     }
44     {
45         std::atomic_flag f;
46         f.clear(std::memory_order_seq_cst);
47         assert(f.test_and_set() == 0);
48         f.clear(std::memory_order_seq_cst);
49         assert(f.test_and_set() == 0);
50     }
51     {
52         volatile std::atomic_flag f;
53         f.clear();
54         assert(f.test_and_set() == 0);
55         f.clear();
56         assert(f.test_and_set() == 0);
57     }
58     {
59         volatile std::atomic_flag f;
60         f.clear(std::memory_order_relaxed);
61         assert(f.test_and_set() == 0);
62         f.clear(std::memory_order_relaxed);
63         assert(f.test_and_set() == 0);
64     }
65     {
66         volatile std::atomic_flag f;
67         f.clear(std::memory_order_release);
68         assert(f.test_and_set() == 0);
69         f.clear(std::memory_order_release);
70         assert(f.test_and_set() == 0);
71     }
72     {
73         volatile std::atomic_flag f;
74         f.clear(std::memory_order_seq_cst);
75         assert(f.test_and_set() == 0);
76         f.clear(std::memory_order_seq_cst);
77         assert(f.test_and_set() == 0);
78     }
79 
80   return 0;
81 }
82