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<title>Conditional Expressions - GNU Compiler Collection (GCC) Internals</title>
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<h4 class="subsection">11.6.3 Conditional Expressions</h4>
<p><a name="index-Conditional-Expressions-2143"></a>
A C <code>?:</code> expression is converted into an <code>if</code> statement with
each branch assigning to the same temporary. So,
<pre class="smallexample"> a = b ? c : d;
</pre>
<p>becomes
<pre class="smallexample"> if (b == 1)
T1 = c;
else
T1 = d;
a = T1;
</pre>
<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>Note that in GIMPLE, <code>if</code> statements are represented using
<code>GIMPLE_COND</code>, as described below.
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