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<a name="Register-Names-14"></a>
<h4 class="subsubsection">9.33.1.2 Register Names</h4>
<a name="index-OpenRISC-registers"></a>
<a name="index-register-names_002c-OpenRISC"></a>

<p>The OpenRISC register file contains 32 general pupose registers.
</p>
<ul>
<li> The 32 general purpose registers are referred to as &lsquo;<samp>r<var>n</var></samp>&rsquo;.

</li><li> The stack pointer register &lsquo;<samp>r1</samp>&rsquo; can be referenced using the alias
&lsquo;<samp>sp</samp>&rsquo;.

</li><li> The frame pointer register &lsquo;<samp>r2</samp>&rsquo; can be referenced using the alias
&lsquo;<samp>fp</samp>&rsquo;.

</li><li> The link register &lsquo;<samp>r9</samp>&rsquo; can be referenced using the alias &lsquo;<samp>lr</samp>&rsquo;.
</li></ul>

<p>Floating point operations use the same general purpose registers.  The
instructions <code>lf.itof.s</code> (single precision) and <code>lf.itof.d</code> (double
precision) can be used to convert integer values to floating point.
Likewise, instructions <code>lf.ftoi.s</code> (single precision) and
<code>lf.ftoi.d</code> (double precision) can be used to convert floating point to
integer.
</p>
<p>OpenRISC also contains privileged special purpose registers (SPRs).  The
SPRs are accessed using the <code>l.mfspr</code> and <code>l.mtspr</code> instructions.
</p>


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