compare_exchange_weak函数直接比较所包含值的物理内容，这可能导致使用(如果底层类型有填充位、陷阱值或相...
8 EXPORT_STDtemplate<class_Ty,class_Other = _Ty> _CONSTEXPR20 _Ty exchange(_Ty& _Val, _Other&& _New_val)noexcept( conjunction_v<is_nothrow_move_constructible<_Ty>, is_nothrow_assignable<_Ty&, _Other>>) {// assign _New_val to _Val, return previous _Val_Ty _Old_val =static_cast...
std::exchange std::make_from_tuple std::launder std::to_chars std::from_chars std::as_const std::source_location 变参数函数 std::bitset std::cmp_equal, cmp_not_equal, cmp_less, cmp_greater, cmp_less_equal, cmp_greater_equal std::in_range std::declval std::forward std::move std...
这个test and exchange操作先后执行的几条指令，虽然每一条都是原子的，但加起来就不是了。
A more intuitive way to readA = std::exchange(B, C)is that A becomes B and B becomes C at the same time. Some competitive programming relevant examples Fibonacci/linear recurrences Writinga = std::exchange(b, a + b)is much easier and less error-prone thanauto tmp = a; a = b; ...
该函数直接比较原子对象所封装的值与expect的物理内容,在某些情况下,对象的比较操作在使用 operator==() 判断时相等,但 compare_exchange_weak 判断时却可能失败,因为对象底层的物理内容中可能存在位对齐或其他逻辑表示相同但是物理表示不同的值(比如 true 和 5,它们在逻辑上都表示"真",但在物理上两者的表示并不相...
bool compare_exchange_weak(std::shared_ptr<T>& expected, std::shared_ptr<T> desired, std::memory_order order = std::memory_order_seq_cst) noexcept; (4) 1) 若底层 std::shared_ptr<T> 存储同 expected 的T* 并与之共享所有权,或若底层指针和 expected 均为空,则从 desired 赋值给底层 ...
_Thr=_STD exchange(_Other._Thr, {});return*this; } thread(constthread&) =delete;//thread对象不能被复制thread&operator=(constthread&) =delete;//thread对象不能被拷贝赋值voidswap(thread& _Other) noexcept {//swap with _Other_STD swap(_Thr, _Other._Thr); ...
std::atomic<int> x(0);int old = x.exchange(1, std::memory_order_acq_rel); 2.6 std::memory_order_seq_cst (顺序一致性) std::memory_order_seq_cst 是最严格的内存顺序。它不仅包含了 std::memory_order_acq_rel 的语义,还保证了全局的顺序一致性。这是默认的内存顺序,也是最易于理解和使用的...
std::exchange std::exit std::extent std::float_denorm_style std::float_round_style std::forward std::forward_as_tuple std::free std::from_chars std::function std::function::assign std::function::function std::function::operator bool std::function::swap std::function::target std::functi...