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| <a name="Instruction-Marker"></a> |
| <h4 class="subsubsection">9.37.3.7 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 |
| ‘<samp>ELF Handling For Thread-Local Storage</samp>’. |
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