diff --git a/src/compiler/heap-refs.h b/src/compiler/heap-refs.h
index 9190bf3190..b268593a48 100644
--- a/src/compiler/heap-refs.h
+++ b/src/compiler/heap-refs.h
@@ -61,8 +61,6 @@ enum class OddballType : uint8_t {
   /* Subtypes of FixedArray */                      \
   V(ObjectBoilerplateDescription)                   \
   V(ScopeInfo)                                      \
-  /* Subtypes of String */                          \
-  V(InternalizedString)                             \
   /* Subtypes of Name */                            \
   V(Symbol)                                         \
   /* Subtypes of HeapObject */                      \
@@ -94,6 +92,7 @@ enum class OddballType : uint8_t {
   V(FixedArray)                               \
   V(FixedDoubleArray)                         \
   /* Subtypes of Name */                      \
+  V(InternalizedString)                       \
   V(String)                                   \
   /* Subtypes of JSReceiver */                \
   V(JSObject)                                 \
diff --git a/src/compiler/js-heap-broker.cc b/src/compiler/js-heap-broker.cc
index b85d7c9b42..0b8fc5ca8a 100644
--- a/src/compiler/js-heap-broker.cc
+++ b/src/compiler/js-heap-broker.cc
@@ -870,10 +870,12 @@ StringData::StringData(JSHeapBroker* broker, ObjectData** storage,
 class InternalizedStringData : public StringData {
  public:
   InternalizedStringData(JSHeapBroker* broker, ObjectData** storage,
-                         Handle<InternalizedString> object)
-      : StringData(broker, storage, object) {
-    DCHECK(!FLAG_turbo_direct_heap_access);
-  }
+                         Handle<InternalizedString> object);
+
+  uint32_t array_index() const { return array_index_; }
+
+ private:
+  uint32_t array_index_;
 };
 
 ObjectData* StringData::GetCharAsString(JSHeapBroker* broker, uint32_t index,
@@ -896,6 +898,11 @@ ObjectData* StringData::GetCharAsString(JSHeapBroker* broker, uint32_t index,
   return result;
 }
 
+InternalizedStringData::InternalizedStringData(
+    JSHeapBroker* broker, ObjectData** storage,
+    Handle<InternalizedString> object)
+    : StringData(broker, storage, object) {}
+
 namespace {
 
 bool IsFastLiteralHelper(Handle<JSObject> boilerplate, int max_depth,