diff --git a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
--- a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -1265,6 +1265,32 @@
     if (UsedInLoop)
       continue;
 
+    // If none operand is used in or after the loop exit block, sinking the
+    // instruction from pre-header to exit block will extend operands'
+    // live range, hence could increase register pressure. The instruction
+    // should not be sinked for conservativeness.
+    bool OperandsUsedAfterLoop = false;
+    for (Value *Op : I->operands()) {
+      if (isa<Constant>(Op)) {
+        continue;
+      }
+      for (Use &U : Op->uses()) {
+        Instruction *User = cast<Instruction>(U.getUser());
+        BasicBlock *UseBB = User->getParent();
+        if (PHINode *P = dyn_cast<PHINode>(User)) {
+          unsigned i =
+            PHINode::getIncomingValueNumForOperand(U.getOperandNo());
+          UseBB = P->getIncomingBlock(i);
+        }
+        if (DT->dominates(ExitBlock, UseBB)) {
+          OperandsUsedAfterLoop = true;
+          break;
+        }
+      }
+    }
+    if (!OperandsUsedAfterLoop)
+      continue;
+
     // Otherwise, sink it to the exit block.
     Instruction *ToMove = &*I;
     bool Done = false;