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<a name="Literal-Directive"></a>
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<p>
Next: <a href="Literal-Position-Directive.html#Literal-Position-Directive" accesskey="n" rel="next">Literal Position Directive</a>, Previous: <a href="Transform-Directive.html#Transform-Directive" accesskey="p" rel="prev">Transform Directive</a>, Up: <a href="Xtensa-Directives.html#Xtensa-Directives" accesskey="u" rel="up">Xtensa Directives</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="literal"></a>
<h4 class="subsubsection">9.53.5.4 literal</h4>
<a name="index-literal-directive"></a>

<p>The <code>.literal</code> directive is used to define literal pool data, i.e.,
read-only 32-bit data accessed via <code>L32R</code> instructions.
</p>
<div class="smallexample">
<pre class="smallexample">    .literal <var>label</var>, <var>value</var>[, <var>value</var>&hellip;]
</pre></div>

<p>This directive is similar to the standard <code>.word</code> directive, except
that the actual location of the literal data is determined by the
assembler and linker, not by the position of the <code>.literal</code>
directive.  Using this directive gives the assembler freedom to locate
the literal data in the most appropriate place and possibly to combine
identical literals.  For example, the code:
</p>
<div class="smallexample">
<pre class="smallexample">    entry sp, 40
    .literal .L1, sym
    l32r    a4, .L1
</pre></div>

<p>can be used to load a pointer to the symbol <code>sym</code> into register
<code>a4</code>.  The value of <code>sym</code> will not be placed between the
<code>ENTRY</code> and <code>L32R</code> instructions; instead, the assembler puts
the data in a literal pool.
</p>
<p>Literal pools are placed by default in separate literal sections;
however, when using the &lsquo;<samp>--text-section-literals</samp>&rsquo;
option (see <a href="Xtensa-Options.html#Xtensa-Options">Command Line Options</a>), the literal
pools for PC-relative mode <code>L32R</code> instructions
are placed in the current section.<a name="DOCF3" href="#FOOT3"><sup>3</sup></a>
These text section literal
pools are created automatically before <code>ENTRY</code> instructions and
manually after &lsquo;<samp>.literal_position</samp>&rsquo; directives (see <a href="Literal-Position-Directive.html#Literal-Position-Directive">literal_position</a>).  If there are no preceding
<code>ENTRY</code> instructions, explicit <code>.literal_position</code> directives
must be used to place the text section literal pools; otherwise,
<code>as</code> will report an error.
</p>
<p>When literals are placed in separate sections, the literal section names
are derived from the names of the sections where the literals are
defined.  The base literal section names are <code>.literal</code> for
PC-relative mode <code>L32R</code> instructions and <code>.lit4</code> for absolute
mode <code>L32R</code> instructions (see <a href="Absolute-Literals-Directive.html#Absolute-Literals-Directive">absolute-literals</a>).  These base names are used for literals defined in
the default <code>.text</code> section.  For literals defined in other
sections or within the scope of a <code>literal_prefix</code> directive
(see <a href="Literal-Prefix-Directive.html#Literal-Prefix-Directive">literal_prefix</a>), the following rules
determine the literal section name:
</p>
<ol>
<li> If the current section is a member of a section group, the literal
section name includes the group name as a suffix to the base
<code>.literal</code> or <code>.lit4</code> name, with a period to separate the base
name and group name.  The literal section is also made a member of the
group.

</li><li> If the current section name (or <code>literal_prefix</code> value) begins with
&ldquo;<code>.gnu.linkonce.<var>kind</var>.</code>&rdquo;, the literal section name is formed
by replacing &ldquo;<code>.<var>kind</var></code>&rdquo; with the base <code>.literal</code> or
<code>.lit4</code> name.  For example, for literals defined in a section named
<code>.gnu.linkonce.t.func</code>, the literal section will be
<code>.gnu.linkonce.literal.func</code> or <code>.gnu.linkonce.lit4.func</code>.

</li><li> If the current section name (or <code>literal_prefix</code> value) ends with
<code>.text</code>, the literal section name is formed by replacing that
suffix with the base <code>.literal</code> or <code>.lit4</code> name.  For example,
for literals defined in a section named <code>.iram0.text</code>, the literal
section will be <code>.iram0.literal</code> or <code>.iram0.lit4</code>.

</li><li> If none of the preceding conditions apply, the literal section name is
formed by adding the base <code>.literal</code> or <code>.lit4</code> name as a
suffix to the current section name (or <code>literal_prefix</code> value).
</li></ol>

<div class="footnote">
<hr>
<h4 class="footnotes-heading">Footnotes</h4>

<h3><a name="FOOT3" href="#DOCF3">(3)</a></h3>
<p>Literals for the
<code>.init</code> and <code>.fini</code> sections are always placed in separate
sections, even when &lsquo;<samp>--text-section-literals</samp>&rsquo; is enabled.</p>
</div>
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Next: <a href="Literal-Position-Directive.html#Literal-Position-Directive" accesskey="n" rel="next">Literal Position Directive</a>, Previous: <a href="Transform-Directive.html#Transform-Directive" accesskey="p" rel="prev">Transform Directive</a>, Up: <a href="Xtensa-Directives.html#Xtensa-Directives" accesskey="u" rel="up">Xtensa Directives</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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