std::atomic_ref<T>::fetch_add

 

C++

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Technical Specifications

 

Atomic operations library

Types

atomic (C++11)

atomic_ref (C++20)

Functions

atomic_storeatomic_store_explicit (C++11)(C++11)

atomic_loadatomic_load_explicit (C++11)(C++11)

atomic_exchangeatomic_exchange_explicit (C++11)(C++11)

atomic_compare_exchange_weakatomic_compare_exchange_weak_explicitatomic_compare_exchange_strongatomic_compare_exchange_strong_explicit (C++11)(C++11)(C++11)(C++11)

atomic_fetch_addatomic_fetch_add_explicit (C++11)(C++11)

atomic_fetch_subatomic_fetch_sub_explicit (C++11)(C++11)

atomic_fetch_andatomic_fetch_and_explicit (C++11)(C++11)

atomic_fetch_oratomic_fetch_or_explicit (C++11)(C++11)

atomic_fetch_xoratomic_fetch_xor_explicit (C++11)(C++11)

atomic_is_lock_free (C++11)

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atomic_flag (C++11)

atomic_flag_test_and_setatomic_flag_test_and_set_explicit (C++11)(C++11)

atomic_flag_clearatomic_flag_clear_explicit (C++11)(C++11)

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atomic_init (C++11)

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memory_order (C++11)

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std::atomic_ref

Member functions

atomic_ref::atomic_ref

atomic_ref::operator=

atomic_ref::is_lock_free

atomic_ref::store

atomic_ref::load

atomic_ref::operator T

atomic_ref::exchange

atomic_ref::compare_exchange_strongatomic_ref::compare_exchange_weak

Constants

atomic_ref::is_always_lock_free

atomic_ref::required_alignment

Specialized member functions

atomic_ref::fetch_add

atomic_ref::fetch_sub

atomic_ref::fetch_and

atomic_ref::fetch_or

atomic_ref::fetch_xor

atomic_ref::operator++atomic_ref::operator++(int)atomic_ref::operator--atomic_ref::operator--(int)

atomic_ref::operator+=atomic_ref::operator-=atomic_ref::operator&=atomic_ref::operator|=atomic_ref::operator^=

 

member only of atomic_ref<Integral> and atomic_ref<Floating> template specializations
T fetch_add( T arg,              std::memory_order order = std::memory_order_seq_cst ) const noexcept;	(1)
member only of atomic_ref<T*> template specialization
T* fetch_add( std::ptrdiff_t arg,               std::memory_order order = std::memory_order_seq_cst ) const noexcept;	(2)

Atomically replaces the current value of the referenced object with the result of arithmetic addition of the value and arg. This operation is a read-modify-write operation. Memory is affected according to the value of order.

For signed integral types, arithmetic is defined to use two’s complement representation. There are no undefined results.

For floating-point types, the floating-point environment in effect may be different from the calling thread's floating-point environment. The operation need not be conform to the corresponding std::numeric_limits traits but is encouraged to do so. If the result is not a representable value for its type, the result is unspecified but the operation otherwise has no undefined behavior.

For T* types, the result may be an undefined address, but the operation otherwise has no undefined behavior. The program is ill-formed if T is not an object type.

Parameters

arg	-	the other argument of arithmetic addition
order	-	memory order constraints to enforce

Return value

The value of the referenced object, immediately preceding the effects of this function.