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Previous: <a href="Substitutions.html#Substitutions" accesskey="p" rel="prev">Substitutions</a>, Up: <a href="Mode-Iterators.html#Mode-Iterators" accesskey="u" rel="up">Mode Iterators</a> &nbsp; [<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="Mode-Iterator-Examples"></a>
<h4 class="subsubsection">17.23.1.3 Mode Iterator Examples</h4>

<p>Here is an example from the MIPS port.  It defines the following
modes and attributes (among others):
</p>
<div class="smallexample">
<pre class="smallexample">(define_mode_iterator GPR [SI (DI &quot;TARGET_64BIT&quot;)])
(define_mode_attr d [(SI &quot;&quot;) (DI &quot;d&quot;)])
</pre></div>

<p>and uses the following template to define both <code>subsi3</code>
and <code>subdi3</code>:
</p>
<div class="smallexample">
<pre class="smallexample">(define_insn &quot;sub&lt;mode&gt;3&quot;
  [(set (match_operand:GPR 0 &quot;register_operand&quot; &quot;=d&quot;)
        (minus:GPR (match_operand:GPR 1 &quot;register_operand&quot; &quot;d&quot;)
                   (match_operand:GPR 2 &quot;register_operand&quot; &quot;d&quot;)))]
  &quot;&quot;
  &quot;&lt;d&gt;subu\t%0,%1,%2&quot;
  [(set_attr &quot;type&quot; &quot;arith&quot;)
   (set_attr &quot;mode&quot; &quot;&lt;MODE&gt;&quot;)])
</pre></div>

<p>This is exactly equivalent to:
</p>
<div class="smallexample">
<pre class="smallexample">(define_insn &quot;subsi3&quot;
  [(set (match_operand:SI 0 &quot;register_operand&quot; &quot;=d&quot;)
        (minus:SI (match_operand:SI 1 &quot;register_operand&quot; &quot;d&quot;)
                  (match_operand:SI 2 &quot;register_operand&quot; &quot;d&quot;)))]
  &quot;&quot;
  &quot;subu\t%0,%1,%2&quot;
  [(set_attr &quot;type&quot; &quot;arith&quot;)
   (set_attr &quot;mode&quot; &quot;SI&quot;)])

(define_insn &quot;subdi3&quot;
  [(set (match_operand:DI 0 &quot;register_operand&quot; &quot;=d&quot;)
        (minus:DI (match_operand:DI 1 &quot;register_operand&quot; &quot;d&quot;)
                  (match_operand:DI 2 &quot;register_operand&quot; &quot;d&quot;)))]
  &quot;&quot;
  &quot;dsubu\t%0,%1,%2&quot;
  [(set_attr &quot;type&quot; &quot;arith&quot;)
   (set_attr &quot;mode&quot; &quot;DI&quot;)])
</pre></div>


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