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<a name="Instruction-Marker"></a>
<h4 class="subsubsection">9.39.3.7 Instruction Marker</h4>
<a name="index-instruction-marker_002c-s390"></a>
<a name="index-s390-instruction-marker"></a>

<p>The thread local storage instruction markers are used by the linker to
perform code optimization.
</p>
<dl compact="compact">
<dt><code>:tls_load</code></dt>
<dd><p>The :tls_load marker is used to flag the load instruction in the initial
exec TLS model that retrieves the offset from the thread pointer to a
thread local storage variable from the GOT.
</p></dd>
<dt><code>:tls_gdcall</code></dt>
<dd><p>The :tls_gdcall marker is used to flag the branch-and-save instruction to
the __tls_get_offset function in the global dynamic TLS model.
</p></dd>
<dt><code>:tls_ldcall</code></dt>
<dd><p>The :tls_ldcall marker is used to flag the branch-and-save instruction to
the __tls_get_offset function in the local dynamic TLS model.
</p></dd>
</dl>

<p>For more information about the thread local storage instruction marker
and the linker optimizations see the ELF extension documentation
&lsquo;<samp>ELF Handling For Thread-Local Storage</samp>&rsquo;.
</p>


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