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| Next: <a href="Manipulating-GIMPLE-statements.html#Manipulating-GIMPLE-statements" accesskey="n" rel="next">Manipulating GIMPLE statements</a>, Previous: <a href="Temporaries.html#Temporaries" accesskey="p" rel="prev">Temporaries</a>, Up: <a href="GIMPLE.html#GIMPLE" accesskey="u" rel="up">GIMPLE</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> |
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| <a name="Operands-1"></a> |
| <h3 class="section">11.5 Operands</h3> |
| <a name="index-Operands"></a> |
| |
| <p>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 |
| </p><div class="smallexample"> |
| <pre class="smallexample">a = b + c + d |
| </pre></div> |
| <p>becomes |
| </p><div class="smallexample"> |
| <pre class="smallexample">T1 = b + c; |
| a = T1 + d; |
| </pre></div> |
| |
| <p>The same rule holds for arguments to a <code>GIMPLE_CALL</code>. |
| </p> |
| <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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| <tr><td align="left" valign="top">• <a href="Compound-Expressions.html#Compound-Expressions" accesskey="1">Compound Expressions</a>:</td><td> </td><td align="left" valign="top"> |
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| <tr><td align="left" valign="top">• <a href="Compound-Lvalues.html#Compound-Lvalues" accesskey="2">Compound Lvalues</a>:</td><td> </td><td align="left" valign="top"> |
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| <tr><td align="left" valign="top">• <a href="Logical-Operators.html#Logical-Operators" accesskey="4">Logical Operators</a>:</td><td> </td><td align="left" valign="top"> |
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