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 <a name="Xtensa-Directives"></a>
 <div class="header">
 <p>
 Previous: <a href="Xtensa-Relaxation.html#Xtensa-Relaxation" accesskey="p" rel="prev">Xtensa Relaxation</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>
 </div>
 <hr>
 <a name="Directives-3"></a>
 <h4 class="subsection">9.52.5 Directives</h4>
 <a name="index-Xtensa-directives"></a>
 <a name="index-directives_002c-Xtensa"></a>

 <p>The Xtensa assembler supports a region-based directive syntax:
 </p>
 <div class="smallexample">
 <pre class="smallexample">    .begin <var>directive</var> [<var>options</var>]
     &hellip;
     .end <var>directive</var>
 </pre></div>

 <p>All the Xtensa-specific directives that apply to a region of code use
 this syntax.
 </p>
 <p>The directive applies to code between the <code>.begin</code> and the
 <code>.end</code>.  The state of the option after the <code>.end</code> reverts to
 what it was before the <code>.begin</code>.
 A nested <code>.begin</code>/<code>.end</code> region can further
 change the state of the directive without having to be aware of its
 outer state.  For example, consider:
 </p>
 <div class="smallexample">
 <pre class="smallexample">    .begin no-transform
 L:  add a0, a1, a2
 </pre><pre class="smallexample">    .begin transform
 M:  add a0, a1, a2
     .end transform
 </pre><pre class="smallexample">N:  add a0, a1, a2
     .end no-transform
 </pre></div>

 <p>The <code>ADD</code> opcodes at <code>L</code> and <code>N</code> in the outer
 <code>no-transform</code> region both result in <code>ADD</code> machine instructions,
 but the assembler selects an <code>ADD.N</code> instruction for the
 <code>ADD</code> at <code>M</code> in the inner <code>transform</code> region.
 </p>
 <p>The advantage of this style is that it works well inside macros which can
 preserve the context of their callers.
 </p>
 <p>The following directives are available:
 </p><table class="menu" border="0" cellspacing="0">
 <tr><td align="left" valign="top">&bull; <a href="Schedule-Directive.html#Schedule-Directive" accesskey="1">Schedule Directive</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Enable instruction scheduling.
 </td></tr>
 <tr><td align="left" valign="top">&bull; <a href="Longcalls-Directive.html#Longcalls-Directive" accesskey="2">Longcalls Directive</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Use Indirect Calls for Greater Range.
 </td></tr>
 <tr><td align="left" valign="top">&bull; <a href="Transform-Directive.html#Transform-Directive" accesskey="3">Transform Directive</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Disable All Assembler Transformations.
 </td></tr>
 <tr><td align="left" valign="top">&bull; <a href="Literal-Directive.html#Literal-Directive" accesskey="4">Literal Directive</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Intermix Literals with Instructions.
 </td></tr>
 <tr><td align="left" valign="top">&bull; <a href="Literal-Position-Directive.html#Literal-Position-Directive" accesskey="5">Literal Position Directive</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Specify Inline Literal Pool Locations.
 </td></tr>
 <tr><td align="left" valign="top">&bull; <a href="Literal-Prefix-Directive.html#Literal-Prefix-Directive" accesskey="6">Literal Prefix Directive</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Specify Literal Section Name Prefix.
 </td></tr>
 <tr><td align="left" valign="top">&bull; <a href="Absolute-Literals-Directive.html#Absolute-Literals-Directive" accesskey="7">Absolute Literals Directive</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Control PC-Relative vs. Absolute Literals.
 </td></tr>
 </table>

 <hr>
 <div class="header">
 <p>
 Previous: <a href="Xtensa-Relaxation.html#Xtensa-Relaxation" accesskey="p" rel="prev">Xtensa Relaxation</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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	<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
	<a name="Xtensa-Directives"></a>
	<div class="header">
	<p>
	Previous: <a href="Xtensa-Relaxation.html#Xtensa-Relaxation" accesskey="p" rel="prev">Xtensa Relaxation</a>, Up: <a href="Xtensa_002dDependent.html#Xtensa_002dDependent" accesskey="u" rel="up">Xtensa-Dependent</a>   [<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>
	</div>
	<hr>
	<a name="Directives-3"></a>
	<h4 class="subsection">9.52.5 Directives</h4>
	<a name="index-Xtensa-directives"></a>
	<a name="index-directives_002c-Xtensa"></a>

	<p>The Xtensa assembler supports a region-based directive syntax:
	</p>
	<div class="smallexample">
	<pre class="smallexample"> .begin <var>directive</var> [<var>options</var>]
	…
	.end <var>directive</var>
	</pre></div>

	<p>All the Xtensa-specific directives that apply to a region of code use
	this syntax.
	</p>
	<p>The directive applies to code between the <code>.begin</code> and the
	<code>.end</code>. The state of the option after the <code>.end</code> reverts to
	what it was before the <code>.begin</code>.
	A nested <code>.begin</code>/<code>.end</code> region can further
	change the state of the directive without having to be aware of its
	outer state. For example, consider:
	</p>
	<div class="smallexample">
	<pre class="smallexample"> .begin no-transform
	L: add a0, a1, a2
	</pre><pre class="smallexample"> .begin transform
	M: add a0, a1, a2
	.end transform
	</pre><pre class="smallexample">N: add a0, a1, a2
	.end no-transform
	</pre></div>

	<p>The <code>ADD</code> opcodes at <code>L</code> and <code>N</code> in the outer
	<code>no-transform</code> region both result in <code>ADD</code> machine instructions,
	but the assembler selects an <code>ADD.N</code> instruction for the
	<code>ADD</code> at <code>M</code> in the inner <code>transform</code> region.
	</p>
	<p>The advantage of this style is that it works well inside macros which can
	preserve the context of their callers.
	</p>
	<p>The following directives are available:
	</p><table class="menu" border="0" cellspacing="0">
	<tr><td align="left" valign="top">• <a href="Schedule-Directive.html#Schedule-Directive" accesskey="1">Schedule Directive</a>:</td><td>  </td><td align="left" valign="top">Enable instruction scheduling.
	</td></tr>
	<tr><td align="left" valign="top">• <a href="Longcalls-Directive.html#Longcalls-Directive" accesskey="2">Longcalls Directive</a>:</td><td>  </td><td align="left" valign="top">Use Indirect Calls for Greater Range.
	</td></tr>
	<tr><td align="left" valign="top">• <a href="Transform-Directive.html#Transform-Directive" accesskey="3">Transform Directive</a>:</td><td>  </td><td align="left" valign="top">Disable All Assembler Transformations.
	</td></tr>
	<tr><td align="left" valign="top">• <a href="Literal-Directive.html#Literal-Directive" accesskey="4">Literal Directive</a>:</td><td>  </td><td align="left" valign="top">Intermix Literals with Instructions.
	</td></tr>
	<tr><td align="left" valign="top">• <a href="Literal-Position-Directive.html#Literal-Position-Directive" accesskey="5">Literal Position Directive</a>:</td><td>  </td><td align="left" valign="top">Specify Inline Literal Pool Locations.
	</td></tr>
	<tr><td align="left" valign="top">• <a href="Literal-Prefix-Directive.html#Literal-Prefix-Directive" accesskey="6">Literal Prefix Directive</a>:</td><td>  </td><td align="left" valign="top">Specify Literal Section Name Prefix.
	</td></tr>
	<tr><td align="left" valign="top">• <a href="Absolute-Literals-Directive.html#Absolute-Literals-Directive" accesskey="7">Absolute Literals Directive</a>:</td><td>  </td><td align="left" valign="top">Control PC-Relative vs. Absolute Literals.
	</td></tr>
	</table>

	<hr>
	<div class="header">
	<p>
	Previous: <a href="Xtensa-Relaxation.html#Xtensa-Relaxation" accesskey="p" rel="prev">Xtensa Relaxation</a>, Up: <a href="Xtensa_002dDependent.html#Xtensa_002dDependent" accesskey="u" rel="up">Xtensa-Dependent</a>   [<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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