diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 307bfa5..4b91677 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -4789,7 +4789,7 @@
   EVT VT = N->getValueType(0);
 
   // fold (cttz c1) -> c2
-  if (isa<ConstantSDNode>(N0))
+  if (isConstantIntBuildVectorOrConstantInt(N0))
     return DAG.getNode(ISD::CTTZ, SDLoc(N), VT, N0);
   return SDValue();
 }
@@ -4799,7 +4799,7 @@
   EVT VT = N->getValueType(0);
 
   // fold (cttz_zero_undef c1) -> c2
-  if (isa<ConstantSDNode>(N0))
+  if (isConstantIntBuildVectorOrConstantInt(N0))
     return DAG.getNode(ISD::CTTZ_ZERO_UNDEF, SDLoc(N), VT, N0);
   return SDValue();
 }