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<a name="Register-Names-13"></a>
<h4 class="subsubsection">9.32.1.2 Register Names</h4>
<a name="index-OpenRISC-registers"></a>
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<p>The OpenRISC register file contains 32 general pupose registers.
</p>
<ul>
<li> The 32 general purpose registers are referred to as ‘<samp>r<var>n</var></samp>’.
</li><li> The stack pointer register ‘<samp>r1</samp>’ can be referenced using the alias
‘<samp>sp</samp>’.
</li><li> The frame pointer register ‘<samp>r2</samp>’ can be referenced using the alias
‘<samp>fp</samp>’.
</li><li> The link register ‘<samp>r9</samp>’ can be referenced using the alias ‘<samp>lr</samp>’.
</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.
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