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67 lines
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<title>Xtensa Relaxation - Using as</title>
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<a name="Xtensa-Relaxation"></a>Next: <a rel="next" accesskey="n" href="Xtensa-Directives.html#Xtensa-Directives">Xtensa Directives</a>,
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Previous: <a rel="previous" accesskey="p" href="Xtensa-Optimizations.html#Xtensa-Optimizations">Xtensa Optimizations</a>,
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Up: <a rel="up" accesskey="u" href="Xtensa_002dDependent.html#Xtensa_002dDependent">Xtensa-Dependent</a>
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<h4 class="subsection">9.36.4 Xtensa Relaxation</h4>
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<p><a name="index-relaxation-1863"></a>
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When an instruction operand is outside the range allowed for that
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particular instruction field, <span class="command">as</span> can transform the code
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to use a functionally-equivalent instruction or sequence of
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instructions. This process is known as <dfn>relaxation</dfn>. This is
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typically done for branch instructions because the distance of the
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branch targets is not known until assembly-time. The Xtensa assembler
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offers branch relaxation and also extends this concept to function
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calls, <code>MOVI</code> instructions and other instructions with immediate
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fields.
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<ul class="menu">
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<li><a accesskey="1" href="Xtensa-Branch-Relaxation.html#Xtensa-Branch-Relaxation">Xtensa Branch Relaxation</a>: Relaxation of Branches.
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<li><a accesskey="2" href="Xtensa-Call-Relaxation.html#Xtensa-Call-Relaxation">Xtensa Call Relaxation</a>: Relaxation of Function Calls.
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<li><a accesskey="3" href="Xtensa-Immediate-Relaxation.html#Xtensa-Immediate-Relaxation">Xtensa Immediate Relaxation</a>: Relaxation of other Immediate Fields.
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