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| <div class="titlepage"><div><div><h2 class="title" style="clear: both"> |
| <a name="align.examples"></a><a class="link" href="examples.html" title="Examples">Examples</a> |
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| <div class="toc"><dl class="toc"> |
| <dt><span class="section"><a href="examples.html#align.examples.aligned_ptr">aligned_ptr and make_aligned</a></span></dt> |
| <dt><span class="section"><a href="examples.html#align.examples.aligned_vector">aligned_vector</a></span></dt> |
| </dl></div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="align.examples.aligned_ptr"></a><a class="link" href="examples.html#align.examples.aligned_ptr" title="aligned_ptr and make_aligned">aligned_ptr and make_aligned</a> |
| </h3></div></div></div> |
| <p> |
| This example presents an alternative to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">unique_ptr</span></code> |
| for objects allocated with the aligned allocation function. It is defined |
| simply by providing an alias template which uses <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">unique_ptr</span></code> |
| with our aligned deleter in place of the default <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">default_delete</span></code> |
| deleter. It also presents an alternative to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">make_unique</span></code> |
| for the creation of these aligned unique pointer objects. It is implemented |
| using our aligned allocation function. |
| </p> |
| <h5> |
| <a name="align.examples.aligned_ptr.h0"></a> |
| <span class="phrase"><a name="align.examples.aligned_ptr.implementation"></a></span><a class="link" href="examples.html#align.examples.aligned_ptr.implementation">Implementation</a> |
| </h5> |
| <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">align</span><span class="special">/</span><span class="identifier">aligned_alloc</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">align</span><span class="special">/</span><span class="identifier">aligned_delete</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">memory</span><span class="special">></span> |
| |
| <span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">></span> |
| <span class="keyword">using</span> <span class="identifier">aligned_ptr</span> <span class="special">=</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">unique_ptr</span><span class="special"><</span><span class="identifier">T</span><span class="special">,</span> |
| <span class="identifier">boost</span><span class="special">::</span><span class="identifier">alignment</span><span class="special">::</span><span class="identifier">aligned_delete</span><span class="special">>;</span> |
| |
| <span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">></span> |
| <span class="keyword">inline</span> <span class="identifier">aligned_ptr</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span> <span class="identifier">make_aligned</span><span class="special">(</span><span class="identifier">Args</span><span class="special">&&...</span> <span class="identifier">args</span><span class="special">)</span> |
| <span class="special">{</span> |
| <span class="keyword">auto</span> <span class="identifier">p</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">alignment</span><span class="special">::</span> |
| <span class="identifier">aligned_alloc</span><span class="special">(</span><span class="keyword">alignof</span><span class="special">(</span><span class="identifier">T</span><span class="special">),</span> <span class="keyword">sizeof</span><span class="special">(</span><span class="identifier">T</span><span class="special">));</span> |
| <span class="keyword">if</span> <span class="special">(!</span><span class="identifier">p</span><span class="special">)</span> <span class="special">{</span> |
| <span class="keyword">throw</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">bad_alloc</span><span class="special">();</span> |
| <span class="special">}</span> |
| <span class="keyword">try</span> <span class="special">{</span> |
| <span class="keyword">auto</span> <span class="identifier">q</span> <span class="special">=</span> <span class="special">::</span><span class="keyword">new</span><span class="special">(</span><span class="identifier">p</span><span class="special">)</span> <span class="identifier">T</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">forward</span><span class="special"><</span><span class="identifier">Args</span><span class="special">>(</span><span class="identifier">args</span><span class="special">)...);</span> |
| <span class="keyword">return</span> <span class="identifier">aligned_ptr</span><span class="special"><</span><span class="identifier">T</span><span class="special">>(</span><span class="identifier">q</span><span class="special">);</span> |
| <span class="special">}</span> <span class="keyword">catch</span> <span class="special">(...)</span> <span class="special">{</span> |
| <span class="identifier">boost</span><span class="special">::</span><span class="identifier">alignment</span><span class="special">::</span><span class="identifier">aligned_free</span><span class="special">(</span><span class="identifier">p</span><span class="special">);</span> |
| <span class="keyword">throw</span><span class="special">;</span> |
| <span class="special">}</span> |
| <span class="special">}</span> |
| </pre> |
| <h5> |
| <a name="align.examples.aligned_ptr.h1"></a> |
| <span class="phrase"><a name="align.examples.aligned_ptr.usage"></a></span><a class="link" href="examples.html#align.examples.aligned_ptr.usage">Usage</a> |
| </h5> |
| <pre class="programlisting"><span class="keyword">struct</span> <span class="keyword">alignas</span><span class="special">(</span><span class="number">16</span><span class="special">)</span> <span class="identifier">type</span> <span class="special">{</span> |
| <span class="keyword">float</span> <span class="identifier">data</span><span class="special">[</span><span class="number">4</span><span class="special">];</span> |
| <span class="special">};</span> |
| |
| <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> |
| <span class="special">{</span> |
| <span class="keyword">auto</span> <span class="identifier">p</span> <span class="special">=</span> <span class="identifier">make_aligned</span><span class="special"><</span><span class="identifier">type</span><span class="special">>();</span> |
| <span class="identifier">p</span><span class="special">-></span><span class="identifier">data</span><span class="special">[</span><span class="number">0</span><span class="special">]</span> <span class="special">=</span> <span class="number">1.0f</span><span class="special">;</span> |
| <span class="special">}</span> |
| </pre> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="align.examples.aligned_vector"></a><a class="link" href="examples.html#align.examples.aligned_vector" title="aligned_vector">aligned_vector</a> |
| </h3></div></div></div> |
| <p> |
| This example presents an alternative to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span></code> |
| that can be used with over-aligned types, and allows specifying a minimum |
| alignment. It is defined simply by providing an alias template which uses |
| <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span></code> with our aligned allocator. |
| </p> |
| <h5> |
| <a name="align.examples.aligned_vector.h0"></a> |
| <span class="phrase"><a name="align.examples.aligned_vector.implementation"></a></span><a class="link" href="examples.html#align.examples.aligned_vector.implementation">Implementation</a> |
| </h5> |
| <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">align</span><span class="special">/</span><span class="identifier">aligned_allocator</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">vector</span><span class="special">></span> |
| |
| <span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">Alignment</span> <span class="special">=</span> <span class="number">1</span><span class="special">></span> |
| <span class="keyword">using</span> <span class="identifier">aligned_vector</span> <span class="special">=</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span><span class="identifier">T</span><span class="special">,</span> |
| <span class="identifier">boost</span><span class="special">::</span><span class="identifier">alignment</span><span class="special">::</span><span class="identifier">aligned_allocator</span><span class="special"><</span><span class="identifier">T</span><span class="special">,</span> <span class="identifier">Alignment</span><span class="special">></span> <span class="special">>;</span> |
| </pre> |
| <h5> |
| <a name="align.examples.aligned_vector.h1"></a> |
| <span class="phrase"><a name="align.examples.aligned_vector.usage"></a></span><a class="link" href="examples.html#align.examples.aligned_vector.usage">Usage</a> |
| </h5> |
| <pre class="programlisting"><span class="keyword">enum</span> <span class="special">{</span> |
| <span class="identifier">cache_line</span> <span class="special">=</span> <span class="number">64</span> |
| <span class="special">};</span> |
| |
| <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> |
| <span class="special">{</span> |
| <span class="identifier">aligned_vector</span><span class="special"><</span><span class="keyword">char</span><span class="special">,</span> <span class="identifier">cache_line</span><span class="special">></span> <span class="identifier">v</span><span class="special">(</span><span class="number">32</span><span class="special">);</span> |
| <span class="identifier">v</span><span class="special">[</span><span class="number">0</span><span class="special">]</span> <span class="special">=</span> <span class="number">1</span><span class="special">;</span> |
| <span class="special">}</span> |
| </pre> |
| </div> |
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| <td align="right"><div class="copyright-footer">Copyright © 2014 Glen Fernandes<p> |
| Distributed under the <a href="http://boost.org/LICENSE_1_0.txt" target="_top">Boost |
| Software License, Version 1.0</a>. |
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