xref: /llvm-project/libcxx/test/std/atomics/atomics.ref/operator_plus_equals.pass.cpp (revision 09e3a360581dc36d0820d3fb6da9bd7cfed87b5d)
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 
11 // integral-type operator+=(integral-type) const noexcept;
12 // floating-point-type operator+=(floating-point-type) const noexcept;
13 // T* operator+=(difference_type) const noexcept;
14 
15 #include <atomic>
16 #include <cassert>
17 #include <concepts>
18 #include <type_traits>
19 #include <utility>
20 
21 #include "atomic_helpers.h"
22 #include "test_helper.h"
23 #include "test_macros.h"
24 
25 template <typename T>
26 concept has_operator_plus_equals = requires { std::declval<T const>() += std::declval<T>(); };
27 
28 template <typename T>
29 struct TestDoesNotHaveOperatorPlusEquals {
30   void operator()() const { static_assert(!has_operator_plus_equals<std::atomic_ref<T>>); }
31 };
32 
33 template <typename T>
34 struct TestOperatorPlusEquals {
35   void operator()() const {
36     if constexpr (std::is_arithmetic_v<T>) {
37       T x(T(1));
38       std::atomic_ref<T> const a(x);
39 
40       std::same_as<T> decltype(auto) y = (a += T(2));
41       assert(y == T(3));
42       assert(x == T(3));
43       ASSERT_NOEXCEPT(a += T(0));
44     } else if constexpr (std::is_pointer_v<T>) {
45       using U = std::remove_pointer_t<T>;
46       U t[9]  = {};
47       T p{&t[1]};
48       std::atomic_ref<T> const a(p);
49 
50       std::same_as<T> decltype(auto) y = (a += 2);
51       assert(y == &t[3]);
52       assert(a == &t[3]);
53       ASSERT_NOEXCEPT(a += 0);
54     } else {
55       static_assert(std::is_void_v<T>);
56     }
57 
58     // memory_order::seq_cst
59     {
60       auto plus_equals = [](std::atomic_ref<T> const& x, T old_val, T new_val) { x += (new_val - old_val); };
61       auto load        = [](std::atomic_ref<T> const& x) { return x.load(); };
62       test_seq_cst<T>(plus_equals, load);
63     }
64   }
65 };
66 
67 int main(int, char**) {
68   TestEachIntegralType<TestOperatorPlusEquals>()();
69 
70   TestOperatorPlusEquals<float>()();
71   TestOperatorPlusEquals<double>()();
72 
73   TestEachPointerType<TestOperatorPlusEquals>()();
74 
75   TestDoesNotHaveOperatorPlusEquals<bool>()();
76   TestDoesNotHaveOperatorPlusEquals<UserAtomicType>()();
77   TestDoesNotHaveOperatorPlusEquals<LargeUserAtomicType>()();
78 
79   return 0;
80 }
81