[llvm] [PowerPC] Support local-dynamic TLS relocation on AIX (PR #66316)

[via llvm-commits]

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@@ -231,12 +231,15 @@ class PPCTargetAsmStreamer : public PPCTargetStreamer {
       MCSymbolXCOFF *TCSym =
           cast<MCSectionXCOFF>(Streamer.getCurrentSectionOnly())
               ->getQualNameSymbol();
-      // On AIX, we have a region handle (symbol at m) and the variable offset
-      // (symbol@{gd|ie|le}) for TLS variables, depending on the TLS model.
+      // On AIX, we have a region handle (symbol at m), module handle
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stephenpeckham wrote:

On AIX, we have TLS variable offsets (symbol@({gd|ie|le|ld}) depending on the TLS access method (or model). For the general-dynamic access method, we also have region handle (symbol at m) for each variable.  For local-dynamic, a module handle (__TLSML[TC]@ml) for all variables. For local-exec and initial-exec, we have a thread pointer, in r13 for 64-bit mode and returned by __get_tpointer for 32-bit mode.

https://github.com/llvm/llvm-project/pull/66316