1//
2// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
3// See https://llvm.org/LICENSE.txt for license information.
4// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
5//
6//===----------------------------------------------------------------------===//
7
8// UNSUPPORTED: c++03, c++11, c++14, c++17
9// UNSUPPORTED: no-threads
10// XFAIL: availability-synchronization_library-missing
11// XFAIL: !has-64-bit-atomics
12// XFAIL: !has-1024-bit-atomics
13
14// MSVC warning C4310: cast truncates constant value
15// ADDITIONAL_COMPILE_FLAGS(cl-style-warnings): /wd4310
16
17// void wait(T, memory_order = memory_order::seq_cst) const noexcept;
18
19#include <atomic>
20#include <cassert>
21#include <type_traits>
22
23#include "atomic_helpers.h"
24#include "make_test_thread.h"
25#include "test_helper.h"
26#include "test_macros.h"
27
28template <typename T>
29struct TestWait {
30 void operator()() const {
31 {
32 T x(T(1));
33 std::atomic_ref<T> const a(x);
34
35 assert(a.load() == T(1));
36 a.wait(T(0));
37 std::thread t1 = support::make_test_thread([&]() {
38 a.store(T(3));
39 a.notify_one();
40 });
41 a.wait(T(1));
42 assert(a.load() == T(3));
43 t1.join();
44 ASSERT_NOEXCEPT(a.wait(T(0)));
45
46 assert(a.load() == T(3));
47 a.wait(T(0), std::memory_order_seq_cst);
48 std::thread t2 = support::make_test_thread([&]() {
49 a.store(T(5));
50 a.notify_one();
51 });
52 a.wait(T(3), std::memory_order_seq_cst);
53 assert(a.load() == T(5));
54 t2.join();
55 ASSERT_NOEXCEPT(a.wait(T(0), std::memory_order_seq_cst));
56 }
57
58 // memory_order::acquire
59 {
60 auto store = [](std::atomic_ref<T> const& x, T, T new_val) { x.store(new_val, std::memory_order::release); };
61 auto load = [](std::atomic_ref<T> const& x) {
62 auto result = x.load(std::memory_order::relaxed);
63 x.wait(T(255), std::memory_order::acquire);
64 return result;
65 };
66 test_acquire_release<T>(store, load);
67 }
68
69 // memory_order::seq_cst
70 {
71 auto store = [](std::atomic_ref<T> const& x, T, T new_val) { x.store(new_val); };
72 auto load_no_arg = [](std::atomic_ref<T> const& x) {
73 auto result = x.load(std::memory_order::relaxed);
74 x.wait(T(255));
75 return result;
76 };
77 auto load_with_order = [](std::atomic_ref<T> const& x) {
78 auto result = x.load(std::memory_order::relaxed);
79 x.wait(T(255), std::memory_order::seq_cst);
80 return result;
81 };
82 test_seq_cst<T>(store, load_no_arg);
83 test_seq_cst<T>(store, load_with_order);
84 }
85 }
86};
87
88int main(int, char**) {
89 TestEachAtomicType<TestWait>()();
90 return 0;
91}
92

source code of libcxx/test/std/atomics/atomics.ref/wait.pass.cpp