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<title>Using as: s390 Literal Pool Entries</title>

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<a name="s390-Literal-Pool-Entries"></a>
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Previous: <a href="s390-Instruction-Marker.html#s390-Instruction-Marker" accesskey="p" rel="prev">s390 Instruction Marker</a>, Up: <a href="s390-Syntax.html#s390-Syntax" accesskey="u" rel="up">s390 Syntax</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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<a name="Literal-Pool-Entries"></a>
<h4 class="subsubsection">9.39.3.8 Literal Pool Entries</h4>
<a name="index-literal-pool-entries_002c-s390"></a>
<a name="index-s390-literal-pool-entries"></a>

<p>A literal pool is a collection of values. To access the values a pointer
to the literal pool is loaded to a register, the literal pool register.
Usually, register %r13 is used as the literal pool register
(<a href="s390-Register.html#s390-Register">s390 Register</a>). Literal pool entries are created by adding the
suffix :lit1, :lit2, :lit4, or :lit8 to the end of an expression for an
instruction operand. The expression is added to the literal pool and the
operand is replaced with the offset to the literal in the literal pool.
</p>
<dl compact="compact">
<dt><code>:lit1</code></dt>
<dd><p>The literal pool entry is created as an 8-bit value. An operand modifier
must not be used for the original expression.
</p></dd>
<dt><code>:lit2</code></dt>
<dd><p>The literal pool entry is created as a 16 bit value. The operand modifier
@got may be used in the original expression. The term &lsquo;<samp>x@got:lit2</samp>&rsquo;
will put the got offset for the global symbol x to the literal pool as
16 bit value.
</p></dd>
<dt><code>:lit4</code></dt>
<dd><p>The literal pool entry is created as a 32-bit value. The operand modifier
@got and @plt may be used in the original expression. The term
&lsquo;<samp>x@got:lit4</samp>&rsquo; will put the got offset for the global symbol x to the
literal pool as a 32-bit value. The term &lsquo;<samp>x@plt:lit4</samp>&rsquo; will put the
plt offset for the global symbol x to the literal pool as a 32-bit value.
</p></dd>
<dt><code>:lit8</code></dt>
<dd><p>The literal pool entry is created as a 64-bit value. The operand modifier
@got and @plt may be used in the original expression. The term
&lsquo;<samp>x@got:lit8</samp>&rsquo; will put the got offset for the global symbol x to the
literal pool as a 64-bit value. The term &lsquo;<samp>x@plt:lit8</samp>&rsquo; will put the
plt offset for the global symbol x to the literal pool as a 64-bit value.
</p></dd>
</dl>

<p>The assembler directive &lsquo;<samp>.ltorg</samp>&rsquo; is used to emit all literal pool
entries to the current position.
</p>
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