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<h4 class="subsection">9.55.4 Xtensa Relaxation</h4>

<p><a name="index-relaxation-2633"></a>
When an instruction operand is outside the range allowed for that
particular instruction field, <samp><span class="command">as</span></samp> can transform the code
to use a functionally-equivalent instruction or sequence of
instructions.  This process is known as <dfn>relaxation</dfn>.  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.

<ul class="menu">
<li><a accesskey="1" href="Xtensa-Branch-Relaxation.html#Xtensa-Branch-Relaxation">Xtensa Branch Relaxation</a>:         Relaxation of Branches. 
<li><a accesskey="2" href="Xtensa-Call-Relaxation.html#Xtensa-Call-Relaxation">Xtensa Call Relaxation</a>:           Relaxation of Function Calls. 
<li><a accesskey="3" href="Xtensa-Jump-Relaxation.html#Xtensa-Jump-Relaxation">Xtensa Jump Relaxation</a>:           Relaxation of Jumps. 
<li><a accesskey="4" href="Xtensa-Immediate-Relaxation.html#Xtensa-Immediate-Relaxation">Xtensa Immediate Relaxation</a>:      Relaxation of other Immediate Fields. 
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