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<a name="Adding-a-new-GIMPLE-statement-code-1"></a>
<h3 class="section">11.11 Adding a new GIMPLE statement code</h3>
<a name="index-Adding-a-new-GIMPLE-statement-code"></a>

<p>The first step in adding a new GIMPLE statement code, is
modifying the file <code>gimple.def</code>, which contains all the GIMPLE
codes.  Then you must add a corresponding gimple_statement_base subclass
located in <code>gimple.h</code>.  This in turn, will require you to add a
corresponding <code>GTY</code> tag in <code>gsstruct.def</code>, and code to handle
this tag in <code>gss_for_code</code> which is located in <code>gimple.c</code>.
</p>
<p>In order for the garbage collector to know the size of the
structure you created in <code>gimple.h</code>, you need to add a case to
handle your new GIMPLE statement in <code>gimple_size</code> which is located
in <code>gimple.c</code>.
</p>
<p>You will probably want to create a function to build the new
gimple statement in <code>gimple.c</code>.  The function should be called
<code>gimple_build_<var>new-tuple-name</var></code>, and should return the new tuple
as a pointer to the appropriate gimple_statement_base subclass.
</p>
<p>If your new statement requires accessors for any members or
operands it may have, put simple inline accessors in
<code>gimple.h</code> and any non-trivial accessors in <code>gimple.c</code> with a
corresponding prototype in <code>gimple.h</code>.
</p>
<p>You should add the new statement subclass to the class hierarchy diagram
in <code>gimple.texi</code>.
</p>


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