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<a name="Xtensa-Relaxation-1"></a>
<h4 class="subsection">9.55.4 Xtensa Relaxation</h4>
<a name="index-relaxation"></a>

<p>When an instruction operand is outside the range allowed for that
particular instruction field, <code>as</code> can transform the code
to use a functionally-equivalent instruction or sequence of
instructions.  This process is known as <em>relaxation</em>.  This is
typically done for branch instructions because the distance of the
branch targets is not known until assembly-time.  The Xtensa assembler
offers branch relaxation and also extends this concept to function
calls, <code>MOVI</code> instructions and other instructions with immediate
fields.
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<table class="menu" border="0" cellspacing="0">
<tr><td align="left" valign="top">&bull; <a href="Xtensa-Branch-Relaxation.html#Xtensa-Branch-Relaxation" accesskey="1">Xtensa Branch Relaxation</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Relaxation of Branches.
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="Xtensa-Call-Relaxation.html#Xtensa-Call-Relaxation" accesskey="2">Xtensa Call Relaxation</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Relaxation of Function Calls.
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="Xtensa-Jump-Relaxation.html#Xtensa-Jump-Relaxation" accesskey="3">Xtensa Jump Relaxation</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Relaxation of Jumps.
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="Xtensa-Immediate-Relaxation.html#Xtensa-Immediate-Relaxation" accesskey="4">Xtensa Immediate Relaxation</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Relaxation of other Immediate Fields.
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