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<title>Using as: Xtensa Options</title>

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<a name="Xtensa-Options"></a>
<div class="header">
<p>
Next: <a href="Xtensa-Syntax.html#Xtensa-Syntax" accesskey="n" rel="next">Xtensa Syntax</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="Command-Line-Options"></a>
<h4 class="subsection">9.53.1 Command Line Options</h4>

<dl compact="compact">
<dt><code>--text-section-literals | --no-text-section-literals</code></dt>
<dd><a name="index-_002d_002dtext_002dsection_002dliterals"></a>
<a name="index-_002d_002dno_002dtext_002dsection_002dliterals"></a>
<p>Control the treatment of literal pools.  The default is
&lsquo;<samp>--no-text-section-literals</samp>&rsquo;, which places literals in
separate sections in the output file.  This allows the literal pool to be
placed in a data RAM/ROM.  With &lsquo;<samp>--text-section-literals</samp>&rsquo;, the
literals are interspersed in the text section in order to keep them as
close as possible to their references.  This may be necessary for large
assembly files, where the literals would otherwise be out of range of the
<code>L32R</code> instructions in the text section.  Literals are grouped into
pools following <code>.literal_position</code> directives or preceding
<code>ENTRY</code> instructions.  These options only affect literals referenced
via PC-relative <code>L32R</code> instructions; literals for absolute mode
<code>L32R</code> instructions are handled separately.
See <a href="Literal-Directive.html#Literal-Directive">literal</a>.
</p>
</dd>
<dt><code>--auto-litpools | --no-auto-litpools</code></dt>
<dd><a name="index-_002d_002dauto_002dlitpools"></a>
<a name="index-_002d_002dno_002dauto_002dlitpools"></a>
<p>Control the treatment of literal pools.  The default is
&lsquo;<samp>--no-auto-litpools</samp>&rsquo;, which in the absence of
&lsquo;<samp>--text-section-literals</samp>&rsquo; places literals in separate sections
in the output file.  This allows the literal pool to be placed in a data
RAM/ROM.  With &lsquo;<samp>--auto-litpools</samp>&rsquo;, the literals are interspersed
in the text section in order to keep them as close as possible to their
references, explicit <code>.literal_position</code> directives are not
required.  This may be necessary for very large functions, where single
literal pool at the beginning of the function may not be reachable by
<code>L32R</code> instructions at the end.  These options only affect
literals referenced via PC-relative <code>L32R</code> instructions; literals
for absolute mode <code>L32R</code> instructions are handled separately.
When used together with &lsquo;<samp>--text-section-literals</samp>&rsquo;,
&lsquo;<samp>--auto-litpools</samp>&rsquo; takes precedence.
See <a href="Literal-Directive.html#Literal-Directive">literal</a>.
</p>
</dd>
<dt><code>--absolute-literals | --no-absolute-literals</code></dt>
<dd><a name="index-_002d_002dabsolute_002dliterals"></a>
<a name="index-_002d_002dno_002dabsolute_002dliterals"></a>
<p>Indicate to the assembler whether <code>L32R</code> instructions use absolute
or PC-relative addressing.  If the processor includes the absolute
addressing option, the default is to use absolute <code>L32R</code>
relocations.  Otherwise, only the PC-relative <code>L32R</code> relocations
can be used.
</p>
</dd>
<dt><code>--target-align | --no-target-align</code></dt>
<dd><a name="index-_002d_002dtarget_002dalign"></a>
<a name="index-_002d_002dno_002dtarget_002dalign"></a>
<p>Enable or disable automatic alignment to reduce branch penalties at some
expense in code size.  See <a href="Xtensa-Automatic-Alignment.html#Xtensa-Automatic-Alignment">Automatic
Instruction Alignment</a>.  This optimization is enabled by default.  Note
that the assembler will always align instructions like <code>LOOP</code> that
have fixed alignment requirements.
</p>
</dd>
<dt><code>--longcalls | --no-longcalls</code></dt>
<dd><a name="index-_002d_002dlongcalls"></a>
<a name="index-_002d_002dno_002dlongcalls"></a>
<p>Enable or disable transformation of call instructions to allow calls
across a greater range of addresses.  See <a href="Xtensa-Call-Relaxation.html#Xtensa-Call-Relaxation">Function Call Relaxation</a>.  This option should be used when call
targets can potentially be out of range.  It may degrade both code size
and performance, but the linker can generally optimize away the
unnecessary overhead when a call ends up within range.  The default is
&lsquo;<samp>--no-longcalls</samp>&rsquo;.
</p>
</dd>
<dt><code>--transform | --no-transform</code></dt>
<dd><a name="index-_002d_002dtransform"></a>
<a name="index-_002d_002dno_002dtransform"></a>
<p>Enable or disable all assembler transformations of Xtensa instructions,
including both relaxation and optimization.  The default is
&lsquo;<samp>--transform</samp>&rsquo;; &lsquo;<samp>--no-transform</samp>&rsquo; should only be used in the
rare cases when the instructions must be exactly as specified in the
assembly source.  Using &lsquo;<samp>--no-transform</samp>&rsquo; causes out of range
instruction operands to be errors.
</p>
</dd>
<dt><code>--rename-section <var>oldname</var>=<var>newname</var></code></dt>
<dd><a name="index-_002d_002drename_002dsection"></a>
<p>Rename the <var>oldname</var> section to <var>newname</var>.  This option can be used
multiple times to rename multiple sections.
</p>
</dd>
<dt><code>--trampolines | --no-trampolines</code></dt>
<dd><a name="index-_002d_002dtrampolines"></a>
<a name="index-_002d_002dno_002dtrampolines"></a>
<p>Enable or disable transformation of jump instructions to allow jumps
across a greater range of addresses.  See <a href="Xtensa-Jump-Relaxation.html#Xtensa-Jump-Relaxation">Jump Trampolines</a>.  This option should be used when jump targets can
potentially be out of range.  In the absence of such jumps this option
does not affect code size or performance.  The default is
&lsquo;<samp>--trampolines</samp>&rsquo;.
</p></dd>
</dl>


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