190 lines
13 KiB
HTML
190 lines
13 KiB
HTML
<!DOCTYPE html>
|
|
<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
|
|
<head><meta http-equiv="x-ua-compatible" content="ie=edge">
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
|
<title>std::atomic_fetch_xor, std::atomic_fetch_xor_explicit</title>
|
|
<link rel="stylesheet" href="ext.css" />
|
|
<link rel="stylesheet" href="site_modules.css" />
|
|
</head>
|
|
<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_atomic_atomic_fetch_xor skin-cppreference2 action-view cpp-navbar">
|
|
<div id="cpp-content-base">
|
|
<div id="content"><a id="top"></a>
|
|
<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>atomic_fetch_xor, <span style="font-size:0.7em; line-height:130%">std::</span>atomic_fetch_xor_explicit</h1>
|
|
<div id="bodyContent">
|
|
<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-atomic.html">atomic</a></span></div>
|
|
<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
|
|
<table class="t-dcl-begin">
|
|
<tbody>
|
|
<tr class="t-dsc-header">
|
|
<td>
|
|
<div>定义于头文件 <code><a href="cpp-header-atomic.html"><atomic></a></code></div>
|
|
</td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num t-dcl-rev-notes t-since-cxx11">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(1)</td>
|
|
<td rowspan="142"><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl">
|
|
<td class="t-dcl-nopad">
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
|
|
<p>T atomic_fetch_xor<span class="br0">(</span> <a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> obj,<br /></p>
|
|
<span class="kw1">typename</span> <a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy4">::</span><span class="me2">value_type</span> arg <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td class="t-dcl-nopad"></td>
|
|
</tr>
|
|
<tr class="t-dcl">
|
|
<td class="t-dcl-nopad">
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
|
|
<p>T atomic_fetch_xor<span class="br0">(</span> <span class="kw4">volatile</span> <a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> obj,<br /></p>
|
|
<span class="kw1">typename</span> <a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy4">::</span><span class="me2">value_type</span> arg <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td class="t-dcl-nopad"></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody></tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num t-dcl-rev-notes t-since-cxx11">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(2)</td>
|
|
<td rowspan="142"><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl">
|
|
<td class="t-dcl-nopad">
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
|
|
<p>T atomic_fetch_xor_explicit<span class="br0">(</span> <a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> obj,<br />
|
|
<span class="kw1">typename</span> <a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy4">::</span><span class="me2">value_type</span> arg,<br /></p>
|
|
<a href="cpp-atomic-memory_order.html"><span class="kw2090">std::<span class="me2">memory_order</span></span></a> order<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td class="t-dcl-nopad"></td>
|
|
</tr>
|
|
<tr class="t-dcl">
|
|
<td class="t-dcl-nopad">
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
|
|
<p>T atomic_fetch_xor_explicit<span class="br0">(</span> <span class="kw4">volatile</span> <a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> obj,<br />
|
|
<span class="kw1">typename</span> <a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy4">::</span><span class="me2">value_type</span> arg,<br /></p>
|
|
<a href="cpp-atomic-memory_order.html"><span class="kw2090">std::<span class="me2">memory_order</span></span></a> order<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td class="t-dcl-nopad"></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody>
|
|
<tr class="t-dcl-sep">
|
|
<td></td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>原子地以 <code>obj</code> 的旧值和 <code>arg</code> 的逐位异或结果替换 <code>obj</code> 所指向的值。返回 <code>obj</code> 先前保有的值。</p>
|
|
<p>如同执行下列内容一般进行运算：</p>
|
|
<div class="t-li1"><span class="t-li">1)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">obj<span class="sy2">-</span><span class="sy1">></span>fetch_xor<span class="br0">(</span>arg<span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">2)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">obj<span class="sy2">-</span><span class="sy1">></span>fetch_xor<span class="br0">(</span>arg, order<span class="br0">)</span></span></span></div>
|
|
<p>若 <code>std::atomic<T></code> 无 <code>fetch_xor</code> 成员（此成员仅对<a href="cpp-atomic-atomic.html#.E5.AF.B9.E6.95.B4.E6.95.B0.E7.B1.BB.E5.9E.8B.E7.9A.84.E7.89.B9.E5.8C.96">整数类型</a>提供），则程序为病式。</p>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
|
|
<table class="t-par-begin">
|
|
<tr class="t-par">
|
|
<td>obj</td>
|
|
<td>-</td>
|
|
<td>指向要修改的原子对象的指针</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>arg</td>
|
|
<td>-</td>
|
|
<td>要和存储于原子对象的值逐位异或的值</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>order</td>
|
|
<td>-</td>
|
|
<td>此操作所用的内存同步书顺序：容许所有值。</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">返回值</span></h3>
|
|
<p><code>*obj</code> 的<a href="cpp-atomic-memory_order.html#.E4.BF.AE.E6.94.B9.E9.A1.BA.E5.BA.8F">修改顺序</a>中立即前趋此函数效果的值。</p>
|
|
<h3><span class="mw-headline" id=".E5.8F.AF.E8.83.BD.E7.9A.84.E5.AE.9E.E7.8E.B0">可能的实现</span></h3>
|
|
<table class="eq-fun-cpp-table">
|
|
<tr>
|
|
<td>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="cpp source-cpp">
|
|
<pre class="de1"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span>
|
|
T atomic_fetch_xor<span class="br0">(</span> <a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> obj, <span class="kw1">typename</span> <a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy4">::</span><span class="me2">value_type</span> arg <span class="br0">)</span>
|
|
<span class="br0">{</span>
|
|
<span class="kw1">return</span> obj<span class="sy2">-</span><span class="sy1">></span>fetch_xor<span class="br0">(</span>arg<span class="br0">)</span><span class="sy4">;</span>
|
|
<span class="br0">}</span></pre></div>
|
|
</div>
|
|
</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
|
|
<table class="metadata plainlinks ambox mbox-small-left ambox-notice" style="">
|
|
<tr>
|
|
<td class="mbox-empty-cell"></td>
|
|
<td class="mbox-text" style="">本节未完成<br />
|
|
原因：暂无示例</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E7.BC.BA.E9.99.B7.E6.8A.A5.E5.91.8A">缺陷报告</span></h3>
|
|
<p>下列更改行为的缺陷报告追溯地应用于以前出版的 C++ 标准。</p>
|
|
<table class="dsctable" style="font-size:0.8em">
|
|
<tr>
|
|
<th>DR</th>
|
|
<th>应用于</th>
|
|
<th>出版时的行为</th>
|
|
<th>正确行为</th>
|
|
</tr>
|
|
<tr>
|
|
<td><a rel="nofollow" class="external text" href="https://wg21.link/P0558R1">P0558R1</a></td>
|
|
<td>C++11</td>
|
|
<td>曾要求准确类型匹配，因为从多个参数推导 <code>T</code></td>
|
|
<td>仅从 <code>atomic</code> 参数推导 <code>T</code></td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-atomic-atomic-fetch_xor.html"><span class="t-lines"><span>fetch_xor</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>原子地进行参数和原子对象的值的逐位异或，并获得先前保有的值<br />
|
|
<span class="t-mark">(<code>std::atomic<T></code> 的公开成员函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-atomic-atomic_fetch_or.html"><span class="t-lines"><span>atomic_fetch_or</span><span>atomic_fetch_or_explicit</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>将原子对象替换为与非原子实参逻辑或的结果，并获得原子对象的先前值<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-atomic-atomic_fetch_and.html"><span class="t-lines"><span>atomic_fetch_and</span><span>atomic_fetch_and_explicit</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>将原子对象替换为与非原子实参逻辑与的结果，并获得原子对象的先前值<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|