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| <title>Using as: Xtensa Relaxation</title> |
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| <h4 class="subsection">9.52.4 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">• <a href="Xtensa-Branch-Relaxation.html#Xtensa-Branch-Relaxation" accesskey="1">Xtensa Branch Relaxation</a>:</td><td> </td><td align="left" valign="top">Relaxation of Branches. |
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| <tr><td align="left" valign="top">• <a href="Xtensa-Call-Relaxation.html#Xtensa-Call-Relaxation" accesskey="2">Xtensa Call Relaxation</a>:</td><td> </td><td align="left" valign="top">Relaxation of Function Calls. |
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| <tr><td align="left" valign="top">• <a href="Xtensa-Immediate-Relaxation.html#Xtensa-Immediate-Relaxation" accesskey="3">Xtensa Immediate Relaxation</a>:</td><td> </td><td align="left" valign="top">Relaxation of other Immediate Fields. |
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