as: s390 Instruction Marker
9.40.3.7 Instruction Marker
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The thread local storage instruction markers are used by the linker to
perform code optimization.
':tls_load'
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.
':tls_gdcall'
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.
':tls_ldcall'
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.
For more information about the thread local storage instruction
marker and the linker optimizations see the ELF extension documentation
'ELF Handling For Thread-Local Storage'.