[TLSVariableHoist] Do not introduce bitcast on llvm.threadlocal.address argument

llvm/lib/Transforms/Scalar/TLSVariableHoist.cpp

@@ -236,10 +236,20 @@ bool TLSVariableHoistPass::tryReplaceTLSCandidate(Function &Fn,
 
   // Generate a bitcast (no type change)
   auto *CastInst = genBitCastInst(Fn, GV);
+  bool InstUsed = false;
 
   // to replace the uses of TLS Candidate
-  for (auto &User : Cand.Users)
+  for (auto &User : Cand.Users) {
+    if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(User.Inst)) {
+      if (II->getIntrinsicID() == Intrinsic::threadlocal_address)
+        continue;
+    }
+    InstUsed = true;
     User.Inst->setOperand(User.OpndIdx, CastInst);
+  }
+
+  if (!InstUsed)
+    CastInst->eraseFromParent();
 
   return true;
 }

llvm/test/CodeGen/X86/tls-no-bitcast.ll

@@ -0,0 +1,25 @@
+; RUN: llc -tls-load-hoist=true -stop-after=tlshoist < %s | FileCheck %s 
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@I58561 = external thread_local global ptr
+
+define i32 @I59676() {
+entry:
+; CHECK: @I59676
+; CHECK-NOT: bitcast
+; CHECK: tail call ptr @llvm.threadlocal.address.p0(ptr @I58561)
+; CHECK-NEXT; tail call ptr @llvm.threadlocal.address.p0(ptr @I58561)
+  %0 = tail call ptr @llvm.threadlocal.address.p0(ptr @I58561)
+  %1 = tail call ptr @llvm.threadlocal.address.p0(ptr @I58561)
+  ret i32 0
+}
+
+; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
+declare nonnull ptr @llvm.threadlocal.address.p0(ptr nonnull) #0
+
+; uselistorder directives
+uselistorder ptr @llvm.threadlocal.address.p0, { 1, 0 }
+
+attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }