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<h3 class="section">11.6 Operands</h3>
<p><a name="index-Operands-2140"></a>
In general, expressions in GIMPLE consist of an operation and the
appropriate number of simple operands; these operands must either be a
GIMPLE rvalue (<code>is_gimple_val</code>), i.e. a constant or a register
variable. More complex operands are factored out into temporaries, so
that
<pre class="smallexample"> a = b + c + d
</pre>
<p>becomes
<pre class="smallexample"> T1 = b + c;
a = T1 + d;
</pre>
<p>The same rule holds for arguments to a <code>GIMPLE_CALL</code>.
<p>The target of an assignment is usually a variable, but can also be a
<code>MEM_REF</code> or a compound lvalue as described below.
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<li><a accesskey="1" href="Compound-Expressions.html#Compound-Expressions">Compound Expressions</a>
<li><a accesskey="2" href="Compound-Lvalues.html#Compound-Lvalues">Compound Lvalues</a>
<li><a accesskey="3" href="Conditional-Expressions.html#Conditional-Expressions">Conditional Expressions</a>
<li><a accesskey="4" href="Logical-Operators.html#Logical-Operators">Logical Operators</a>
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