[clang] [llvm] [PowerPC] Tune AIX shared library TLS model at function level by heuristic (PR #84132)

[Amy Kwan via cfe-commits]

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@@ -4958,6 +4958,10 @@ def maix_small_local_exec_tls : Flag<["-"], "maix-small-local-exec-tls">,
            "where the offset from the TLS base is encoded as an "
            "immediate operand (AIX 64-bit only). "
            "This access sequence is not used for variables larger than 32KB.">;
+def maix_shared_library_tls_model_heuristic : Flag<["-"], "maix-shared-library-tls-model-heuristic">,
+  Group<m_ppc_Features_Group>,
+  HelpText<"For shared library loaded with the main program, use heuristic to "
+           "tune TLS model at function level (AIX 64-bit only).">;
----------------
amy-kwan wrote:

```suggestion
  HelpText<"For shared library loaded with the main program, use heuristics to "
           "tune the TLS model at the function level (AIX 64-bit only).">;
```

https://github.com/llvm/llvm-project/pull/84132