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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. |
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| <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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