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

[via llvm-commits]

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@@ -660,14 +671,16 @@ void PPCAsmPrinter::EmitTlsCall(const MachineInstr *MI,
          "GETtls[ld]ADDR[32] must read GPR3");
 
   if (Subtarget->isAIXABI()) {
-    // On AIX, the variable offset should already be in R4 and the region handle
-    // should already be in R3.
-    // For TLSGD, which currently is the only supported access model, we only
-    // need to generate an absolute branch to .__tls_get_addr.
+    // For TLSGD, the variable offset should already be in R4 and the region
+    // handle should already be in R3, generate absolute branch to
+    // .__tls_get_addr. For TLSLD, the module handle should already be in R3,
+    // generate branch to .__tls_get_mod.
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stephenpeckham wrote:

```suggestion
    // We generate an absolute branch to .__tls_get_mod.
```

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