xref: /llvm-project/libcxx/test/std/atomics/atomics.ref/load.pass.cpp (revision 42ba740afffa16f991be6aa36626bd872d41ebc0)
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 // XFAIL: !has-64-bit-atomics
10 // XFAIL: !has-1024-bit-atomics
11 
12 // T load(memory_order = memory_order::seq_cst) const noexcept;
13 
14 #include <atomic>
15 #include <concepts>
16 #include <cassert>
17 #include <type_traits>
18 
19 #include "atomic_helpers.h"
20 #include "test_helper.h"
21 #include "test_macros.h"
22 
23 template <typename T>
24 struct TestLoad {
operator ()TestLoad25   void operator()() const {
26     T x(T(1));
27     std::atomic_ref<T> const a(x);
28 
29     {
30       std::same_as<T> decltype(auto) y = a.load();
31       assert(y == T(1));
32       ASSERT_NOEXCEPT(a.load());
33     }
34 
35     {
36       std::same_as<T> decltype(auto) y = a.load(std::memory_order_seq_cst);
37       assert(y == T(1));
38       ASSERT_NOEXCEPT(a.load(std::memory_order_seq_cst));
39     }
40 
41     // memory_order::seq_cst
42     {
43       auto store           = [](std::atomic_ref<T> const& y, T, T new_val) { y.store(new_val); };
44       auto load_no_arg     = [](std::atomic_ref<T> const& y) { return y.load(); };
45       auto load_with_order = [](std::atomic_ref<T> const& y) { return y.load(std::memory_order::seq_cst); };
46       test_seq_cst<T>(store, load_no_arg);
47       test_seq_cst<T>(store, load_with_order);
48     }
49 
50     // memory_order::release
51     {
52       auto store = [](std::atomic_ref<T> const& y, T, T new_val) { y.store(new_val, std::memory_order::release); };
53       auto load  = [](std::atomic_ref<T> const& y) { return y.load(std::memory_order::acquire); };
54       test_acquire_release<T>(store, load);
55     }
56   }
57 };
58 
main(int,char **)59 int main(int, char**) {
60   TestEachAtomicType<TestLoad>()();
61   return 0;
62 }
63