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<title>Using as: Xtensa Relaxation</title>
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<a name="Xtensa-Relaxation"></a>
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Next: <a href="Xtensa-Directives.html#Xtensa-Directives" accesskey="n" rel="next">Xtensa Directives</a>, Previous: <a href="Xtensa-Optimizations.html#Xtensa-Optimizations" accesskey="p" rel="prev">Xtensa Optimizations</a>, Up: <a href="Xtensa_002dDependent.html#Xtensa_002dDependent" accesskey="u" rel="up">Xtensa-Dependent</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Xtensa-Relaxation-1"></a>
<h4 class="subsection">9.53.4 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.
</p>
<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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