diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index dd7781bca0..9bd0b90b4c 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -1579,6 +1579,9 @@ class HForceRepresentation V8_FINAL : public HTemplateInstruction<1> {
 
   DECLARE_CONCRETE_INSTRUCTION(ForceRepresentation)
 
+ protected:
+  virtual int RedefinedOperandIndex() { return 0; }
+
  private:
   HForceRepresentation(HValue* value, Representation required_representation) {
     SetOperandAt(0, value);
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 7c42a3bcd6..33586f347e 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -2100,10 +2100,10 @@ void HGraphBuilder::BuildFillElementsWithHole(HValue* elements,
   static const int kLoopUnfoldLimit = 4;
   bool unfold_loop = false;
   int initial_capacity = JSArray::kPreallocatedArrayElements;
-  if (from->IsConstant() && to->IsConstant() &&
+  if (from->ActualValue()->IsConstant() && to->ActualValue()->IsConstant() &&
       initial_capacity <= kLoopUnfoldLimit) {
-    HConstant* constant_from = HConstant::cast(from);
-    HConstant* constant_to = HConstant::cast(to);
+    HConstant* constant_from = HConstant::cast(from->ActualValue());
+    HConstant* constant_to = HConstant::cast(to->ActualValue());
 
     if (constant_from->HasInteger32Value() &&
         constant_from->Integer32Value() == 0 &&