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<a name="Int-Iterators"></a>
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<a name="Int-Iterators-1"></a>
<h4 class="subsection">16.23.3 Int Iterators</h4>
<a name="index-int-iterators-in-_002emd-files"></a>
<a name="index-define_005fint_005fiterator"></a>
<a name="index-define_005fint_005fattr"></a>

<p>Int iterators operate in a similar way to code iterators.  See <a href="Code-Iterators.html#Code-Iterators">Code Iterators</a>.
</p>
<p>The construct:
</p>
<div class="smallexample">
<pre class="smallexample">(define_int_iterator <var>name</var> [(<var>int1</var> &quot;<var>cond1</var>&quot;) &hellip; (<var>intn</var> &quot;<var>condn</var>&quot;)])
</pre></div>

<p>defines a pseudo integer constant <var>name</var> that can be instantiated as
<var>inti</var> if condition <var>condi</var> is true.  Each <var>int</var>
must have the same rtx format.  See <a href="RTL-Classes.html#RTL-Classes">RTL Classes</a>. Int iterators can appear
in only those rtx fields that have &rsquo;i&rsquo; as the specifier. This means that
each <var>int</var> has to be a constant defined using define_constant or
define_c_enum.
</p>
<p>As with mode and code iterators, each pattern that uses <var>name</var> will be
expanded <var>n</var> times, once with all uses of <var>name</var> replaced by
<var>int1</var>, once with all uses replaced by <var>int2</var>, and so on.
See <a href="Defining-Mode-Iterators.html#Defining-Mode-Iterators">Defining Mode Iterators</a>.
</p>
<p>It is possible to define attributes for ints as well as for codes and modes.
Attributes are defined using:
</p>
<div class="smallexample">
<pre class="smallexample">(define_int_attr <var>name</var> [(<var>int1</var> &quot;<var>value1</var>&quot;) &hellip; (<var>intn</var> &quot;<var>valuen</var>&quot;)])
</pre></div>

<p>Here&rsquo;s an example of int iterators in action, taken from the ARM port:
</p>
<div class="smallexample">
<pre class="smallexample">(define_int_iterator QABSNEG [UNSPEC_VQABS UNSPEC_VQNEG])

(define_int_attr absneg [(UNSPEC_VQABS &quot;abs&quot;) (UNSPEC_VQNEG &quot;neg&quot;)])

(define_insn &quot;neon_vq&lt;absneg&gt;&lt;mode&gt;&quot;
  [(set (match_operand:VDQIW 0 &quot;s_register_operand&quot; &quot;=w&quot;)
	(unspec:VDQIW [(match_operand:VDQIW 1 &quot;s_register_operand&quot; &quot;w&quot;)
		       (match_operand:SI 2 &quot;immediate_operand&quot; &quot;i&quot;)]
		      QABSNEG))]
  &quot;TARGET_NEON&quot;
  &quot;vq&lt;absneg&gt;.&lt;V_s_elem&gt;\t%&lt;V_reg&gt;0, %&lt;V_reg&gt;1&quot;
  [(set_attr &quot;type&quot; &quot;neon_vqneg_vqabs&quot;)]
)

</pre></div>

<p>This is equivalent to:
</p>
<div class="smallexample">
<pre class="smallexample">(define_insn &quot;neon_vqabs&lt;mode&gt;&quot;
  [(set (match_operand:VDQIW 0 &quot;s_register_operand&quot; &quot;=w&quot;)
	(unspec:VDQIW [(match_operand:VDQIW 1 &quot;s_register_operand&quot; &quot;w&quot;)
		       (match_operand:SI 2 &quot;immediate_operand&quot; &quot;i&quot;)]
		      UNSPEC_VQABS))]
  &quot;TARGET_NEON&quot;
  &quot;vqabs.&lt;V_s_elem&gt;\t%&lt;V_reg&gt;0, %&lt;V_reg&gt;1&quot;
  [(set_attr &quot;type&quot; &quot;neon_vqneg_vqabs&quot;)]
)

(define_insn &quot;neon_vqneg&lt;mode&gt;&quot;
  [(set (match_operand:VDQIW 0 &quot;s_register_operand&quot; &quot;=w&quot;)
	(unspec:VDQIW [(match_operand:VDQIW 1 &quot;s_register_operand&quot; &quot;w&quot;)
		       (match_operand:SI 2 &quot;immediate_operand&quot; &quot;i&quot;)]
		      UNSPEC_VQNEG))]
  &quot;TARGET_NEON&quot;
  &quot;vqneg.&lt;V_s_elem&gt;\t%&lt;V_reg&gt;0, %&lt;V_reg&gt;1&quot;
  [(set_attr &quot;type&quot; &quot;neon_vqneg_vqabs&quot;)]
)

</pre></div>

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