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<h5 class="subsubsection">9.38.3.7 Instruction Marker</h5>
<p><a name="index-instruction-marker_002c-s390-1903"></a><a name="index-s390-instruction-marker-1904"></a>
The thread local storage instruction markers are used by the linker to
perform code optimization.
<dl>
<dt><code>:tls_load</code><dd>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.
<br><dt><code>:tls_gdcall</code><dd>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.
<br><dt><code>:tls_ldcall</code><dd>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.
</dl>
<p>For more information about the thread local storage instruction marker
and the linker optimizations see the ELF extension documentation
‘<samp><span class="samp">ELF Handling For Thread-Local Storage</span></samp>’.
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