diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 2b169b7..37263ff 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -1984,12 +1984,12 @@
     N0IsConst = isConstantSplatVector(N0.getNode(), ConstValue0);
     N1IsConst = isConstantSplatVector(N1.getNode(), ConstValue1);
   } else {
-    N0IsConst = dyn_cast<ConstantSDNode>(N0) != nullptr;
-    ConstValue0 = N0IsConst ? (dyn_cast<ConstantSDNode>(N0))->getAPIntValue()
-                            : APInt();
-    N1IsConst = dyn_cast<ConstantSDNode>(N1) != nullptr;
-    ConstValue1 = N1IsConst ? (dyn_cast<ConstantSDNode>(N1))->getAPIntValue()
-                            : APInt();
+    N0IsConst = isa<ConstantSDNode>(N0);
+    if (N0IsConst)
+      ConstValue0 = cast<ConstantSDNode>(N0)->getAPIntValue();
+    N1IsConst = isa<ConstantSDNode>(N1);
+    if (N1IsConst)
+      ConstValue1 = cast<ConstantSDNode>(N1)->getAPIntValue();
   }
 
   // fold (mul c1, c2) -> c1*c2
@@ -11662,7 +11662,7 @@
     // type.
     if (V->getOperand(0).getValueType() != NVT)
       return SDValue();
-    unsigned Idx = dyn_cast<ConstantSDNode>(N->getOperand(1))->getZExtValue();
+    unsigned Idx = N->getConstantOperandVal(1);
     unsigned NumElems = NVT.getVectorNumElements();
     assert((Idx % NumElems) == 0 &&
            "IDX in concat is not a multiple of the result vector length.");