[clang] [Clang] Access tls_guard via llvm.threadlocal.address (PR #96633)

[John McCall via cfe-commits]

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@@ -2933,7 +2933,8 @@ void ItaniumCXXABI::EmitThreadLocalInitFuncs(
     Guard->setAlignment(GuardAlign.getAsAlign());
 
     CodeGenFunction(CGM).GenerateCXXGlobalInitFunc(
-        InitFunc, OrderedInits, ConstantAddress(Guard, CGM.Int8Ty, GuardAlign));
+        InitFunc, OrderedInits, ConstantAddress(Guard, CGM.Int8Ty, GuardAlign),
+        Guard->isThreadLocal());
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rjmccall wrote:

```suggestion
        /*IsTLS*/ true);
```

https://github.com/llvm/llvm-project/pull/96633