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<h1 id="firstHeading" class="firstHeading mw-first-heading">
<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Task skipping</span></span>
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<p><b>Task skipping</b> is an <a href="Approximate_computing" title="Approximate computing">approximate computing</a> technique that allows to skip <a href="Code_block" class="mw-redirect" title="Code block">code blocks</a> according to a specific <a href="Boolean_data_type" title="Boolean data type">boolean</a> condition to be checked at <a href="Run_time_(program_lifecycle_phase)" class="mw-redirect" title="Run time (program lifecycle phase)">run-time</a>.
</p><p>This technique is usually applied on the most computational-intensive section of the code.
</p><p>It relies on the fact that a <a href="Tuple" title="Tuple">tuple</a> of values sequentially computed are going to be useful only if the whole tuple meet certain conditions. Knowing that a value of the tuple invalides or probably will invalidate the whole tuple, it is possible to avoid the computation of the rest of the tuple.
</p>
<div class="mw-heading mw-heading2"><h2 id="Code_example">Code example</h2></div>
<p>The example that follows provides the result of task skipping applied on this <a href="C_(programming_language)" title="C (programming language)">C</a>-like source code
</p>
<div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre><span class="k">for</span><span class="w"> </span><span class="p">(</span><span class="kt">int</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o"><</span><span class="w"> </span><span class="n">N</span><span class="p">;</span><span class="w"> </span><span class="n">i</span><span class="o">++</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="n">value_1</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">compute_1</span><span class="p">(</span><span class="n">i</span><span class="p">);</span>
<span class="w"> </span><span class="n">value_2</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">compute_2</span><span class="p">(</span><span class="n">i</span><span class="p">);</span>
<span class="p">}</span>
</pre></div>
<div class="mw-heading mw-heading3"><h3 id="Skipping_a_task">Skipping a task</h3></div>
<div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre><span class="k">for</span><span class="w"> </span><span class="p">(</span><span class="kt">int</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o"><</span><span class="w"> </span><span class="n">N</span><span class="p">;</span><span class="w"> </span><span class="n">i</span><span class="o">++</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="n">value_1</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">compute_1</span><span class="p">(</span><span class="n">i</span><span class="p">);</span>
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">value_1</span><span class="w"> </span><span class="o">>=</span><span class="w"> </span><span class="n">fixed_threshold</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="n">value_2</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">compute_2</span><span class="p">(</span><span class="n">i</span><span class="p">);</span>
<span class="w"> </span><span class="p">}</span>
<span class="p">}</span>
</pre></div>
<div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2></div>
<ul><li><a href="Loop_perforation" title="Loop perforation">Loop perforation</a></li>
<li><a href="Memoization" title="Memoization">Memoization</a></li></ul>
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This article is issued from <a class="external text" title="Last edited on 2021-05-11" href="https://en.wikipedia.org/wiki/?title=Task_skipping&oldid=1022543015">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.
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