[lld] [lldb] [llvm] [AArch64] Support TLS variables in debug info (PR #146572)

[Igor Kudrin via llvm-commits]

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@@ -274,9 +274,17 @@ void DwarfCompileUnit::addLocationAttribute(
     if (!Global && (!Expr || !Expr->isConstant()))
       continue;
 
-    if (Global && Global->isThreadLocal() &&
-        !Asm->getObjFileLowering().supportDebugThreadLocalLocation())
-      continue;
+    if (Global && Global->isThreadLocal()) {
+      // Do not emit TLS location for preemptible TLS variables
+      // (e.g. TLS in shared libraries). The TLS offset cannot be
+      // represented safely in DWARF. In that case let Debugger use
+      // Runtime TLS lookup via DTV (Dynmic thread vector).
+      if (Asm->TM.getTargetTriple().isAArch64() && !Global->isDSOLocal())
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igorkudrin wrote:

What caused the failures in X86 test cases?

https://github.com/llvm/llvm-project/pull/146572