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<h4 class="subsection">12.6.3 Conditional Expressions</h4>
<a name="index-Conditional-Expressions"></a>

<p>A C <code>?:</code> expression is converted into an <code>if</code> statement with
each branch assigning to the same temporary.  So,
</p>
<div class="smallexample">
<pre class="smallexample">a = b ? c : d;
</pre></div>
<p>becomes
</p><div class="smallexample">
<pre class="smallexample">if (b == 1)
  T1 = c;
else
  T1 = d;
a = T1;
</pre></div>

<p>The GIMPLE level if-conversion pass re-introduces <code>?:</code>
expression, if appropriate. It is used to vectorize loops with
conditions using vector conditional operations.
</p>
<p>Note that in GIMPLE, <code>if</code> statements are represented using
<code>GIMPLE_COND</code>, as described below.
</p>


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