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79 lines
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79 lines
3.1 KiB
HTML
4 years ago
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<title>Conditional Expressions - GNU Compiler Collection (GCC) Internals</title>
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<meta name="description" content="GNU Compiler Collection (GCC) Internals">
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<link rel="up" href="Operands.html#Operands" title="Operands">
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<link rel="prev" href="Compound-Lvalues.html#Compound-Lvalues" title="Compound Lvalues">
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<link rel="next" href="Logical-Operators.html#Logical-Operators" title="Logical Operators">
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Permission is granted to copy, distribute and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.3 or
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A GNU Manual
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<body>
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<div class="node">
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<a name="Conditional-Expressions"></a>
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<p>
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Next: <a rel="next" accesskey="n" href="Logical-Operators.html#Logical-Operators">Logical Operators</a>,
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Previous: <a rel="previous" accesskey="p" href="Compound-Lvalues.html#Compound-Lvalues">Compound Lvalues</a>,
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Up: <a rel="up" accesskey="u" href="Operands.html#Operands">Operands</a>
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<hr>
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</div>
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<h4 class="subsection">11.6.3 Conditional Expressions</h4>
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<p><a name="index-Conditional-Expressions-2143"></a>
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A C <code>?:</code> expression is converted into an <code>if</code> statement with
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each branch assigning to the same temporary. So,
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<pre class="smallexample"> a = b ? c : d;
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</pre>
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<p>becomes
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<pre class="smallexample"> if (b == 1)
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T1 = c;
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else
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T1 = d;
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a = T1;
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</pre>
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<p>The GIMPLE level if-conversion pass re-introduces <code>?:</code>
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expression, if appropriate. It is used to vectorize loops with
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conditions using vector conditional operations.
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<p>Note that in GIMPLE, <code>if</code> statements are represented using
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<code>GIMPLE_COND</code>, as described below.
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</body></html>
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