聚合国内IT技术精华文章,分享IT技术精华,帮助IT从业人士成长

C++11 并发指南六(atomic 类型详解三 std::atomic (续)) - Haippy

2013-09-06 15:00 浏览: 1168339 次 我要评论(0 条) 字号:

C++11 并发指南六( <atomic> 类型详解二 std::atomic ) 介绍了基本的原子类型 std::atomic 的用法,本节我会给大家介绍C++11 标准库中的 std::atomic 针对整形(integral)和指针类型的特化版本做了哪些改进。

总地来说,C++11 标准库中的 std::atomic 针对整形(integral)和指针类型的特化版本新增了一些算术运算和逻辑运算操作。具体如下:

integral fetch_add(integral, memory_order = memory_order_seq_cst) volatile;
integral fetch_add(integral, memory_order = memory_order_seq_cst);
integral fetch_sub(integral, memory_order = memory_order_seq_cst) volatile;
integral fetch_sub(integral, memory_order = memory_order_seq_cst);
integral fetch_and(integral, memory_order = memory_order_seq_cst) volatile;
integral fetch_and(integral, memory_order = memory_order_seq_cst);
integral fetch_or(integral, memory_order = memory_order_seq_cst) volatile;
integral fetch_or(integral, memory_order = memory_order_seq_cst);
integral fetch_xor(integral, memory_order = memory_order_seq_cst) volatile;
integral fetch_xor(integral, memory_order = memory_order_seq_cst);

integral operator++(int) volatile;
integral operator++(int);
integral operator--(int) volatile;
integral operator--(int);
integral operator++() volatile;
integral operator++();
integral operator--() volatile;
integral operator--();
integral operator+=(integral) volatile;
integral operator+=(integral);
integral operator-=(integral) volatile;
integral operator-=(integral);
integral operator&=(integral) volatile;
integral operator&=(integral);
integral operator|=(integral) volatile;
integral operator|=(integral);
integral operator^=(integral) volatile;
integral operator^=(integral);

 下面我们来简单介绍以上的 std::atomic 特化版本的成员函数。

if T is integral (1)
T fetch_add (T val, memory_order sync = memory_order_seq_cst) volatile noexcept;
T fetch_add (T val, memory_order sync = memory_order_seq_cst) noexcept;
if T is pointer (2)
T fetch_add (ptrdiff_t val, memory_order sync = memory_order_seq_cst) volatile noexcept;
T fetch_add (ptrdiff_t val, memory_order sync = memory_order_seq_cst) noexcept;
Memory Order 值Memory Order 类型
memory_order_relaxedRelaxed
memory_order_consumeConsume
memory_order_acquireAcquire
memory_order_releaseRelease
memory_order_acq_relAcquire/Release
memory_order_seq_cstSequentially consistent
if T is integral (1)
T fetch_sub (T val, memory_order sync = memory_order_seq_cst) volatile noexcept;
T fetch_sub (T val, memory_order sync = memory_order_seq_cst) noexcept;
if T is pointer (2)
T fetch_sub (ptrdiff_t val, memory_order sync = memory_order_seq_cst) volatile noexcept;
T fetch_sub (ptrdiff_t val, memory_order sync = memory_order_seq_cst) noexcept;
Memory Order 值Memory Order 类型
memory_order_relaxedRelaxed
memory_order_consumeConsume
memory_order_acquireAcquire
memory_order_releaseRelease
memory_order_acq_relAcquire/Release
memory_order_seq_cstSequentially consistent
T fetch_and (T val, memory_order sync = memory_order_seq_cst) volatile noexcept;
T fetch_and (T val, memory_order sync = memory_order_seq_cst) noexcept;

 

Memory Order 值Memory Order 类型
memory_order_relaxedRelaxed
memory_order_consumeConsume
memory_order_acquireAcquire
memory_order_releaseRelease
memory_order_acq_relAcquire/Release
memory_order_seq_cstSequentially consistent
T fetch_or (T val, memory_order sync = memory_order_seq_cst) volatile noexcept;
T fetch_or (T val, memory_order sync = memory_order_seq_cst) noexcept;

 

Memory Order 值Memory Order 类型
memory_order_relaxedRelaxed
memory_order_consumeConsume
memory_order_acquireAcquire
memory_order_releaseRelease
memory_order_acq_relAcquire/Release
memory_order_seq_cstSequentially consistent
T fetch_xor (T val, memory_order sync = memory_order_seq_cst) volatile noexcept;
T fetch_xor (T val, memory_order sync = memory_order_seq_cst) noexcept;
Memory Order 值Memory Order 类型
memory_order_relaxedRelaxed
memory_order_consumeConsume
memory_order_acquireAcquire
memory_order_releaseRelease
memory_order_acq_relAcquire/Release
memory_order_seq_cstSequentially consistent
pre-increment (1)
T operator++() volatile noexcept;
T operator++() noexcept;
post-increment (2)
T operator++ (int) volatile noexcept;
T operator++ (int) noexcept;
if T is integral (1)
T operator+= (T val) volatile noexcept;
T operator+= (T val) noexcept;
T operator-= (T val) volatile noexcept;
T operator-= (T val) noexcept;
T operator&= (T val) volatile noexcept;
T operator&= (T val) noexcept;
T operator|= (T val) volatile noexcept;
T operator|= (T val) noexcept;
T operator^= (T val) volatile noexcept;
T operator^= (T val) noexcept;
if T is pointer (2)
T operator+= (ptrdiff_t val) volatile noexcept;
T operator+= (ptrdiff_t val) noexcept;
T operator-= (ptrdiff_t val) volatile noexcept;
T operator-= (ptrdiff_t val) noexcept;

以上各个 operator 都会有对应的 fetch_* 操作,详细见下表:

操作符成员函数支持类型
复合赋值等价于整型指针类型其他类型
+atomic::operator+=atomic::fetch_add
-atomic::operator-=atomic::fetch_sub
&atomic::operator&=atomic::fetch_and
|atomic::operator|=atomic::fetch_or
^atomic::operator^=atomic::fetch_xor

好了,本节先介绍这里,下一节我会介绍 C++11 中 C 风格的原子操作 API。



网友评论已有0条评论, 我也要评论

发表评论

*

* (保密)

Ctrl+Enter 快捷回复