Remove extra bitcast instruction in case of no use

Author: abhishek-kaushik22

llvm/lib/Transforms/Scalar/TLSVariableHoist.cpp

@@ -236,16 +236,21 @@ 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) {
     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;
 }