--- old/src/hotspot/share/ci/ciType.hpp	2019-03-11 14:25:30.758355645 +0100
+++ new/src/hotspot/share/ci/ciType.hpp	2019-03-11 14:25:30.506355648 +0100
@@ -29,12 +29,13 @@
 
 // ciType
 //
-// This class represents either a class (T_OBJECT), array (T_ARRAY),
-// or one of the primitive types such as T_INT.
+// This class represents either a class (T_OBJECT), value (T_VALUETYPE),
+// array (T_ARRAY), or one of the primitive types such as T_INT.
 class ciType : public ciMetadata {
   CI_PACKAGE_ACCESS
   friend class ciKlass;
   friend class ciReturnAddress;
+  friend class ciWrapper;
 
 private:
   BasicType _basic_type;
@@ -67,7 +68,7 @@
   ciKlass*  box_klass();
 
   // Returns true if this is not a klass or array (i.e., not a reference type).
-  bool is_primitive_type() const            { return basic_type() != T_OBJECT && basic_type() != T_ARRAY; }
+  bool is_primitive_type() const            { return basic_type() != T_OBJECT && basic_type() != T_ARRAY && basic_type() != T_VALUETYPE; }
   int size() const                          { return type2size[basic_type()]; }
   bool is_void() const                      { return basic_type() == T_VOID; }
   bool is_one_word() const                  { return size() == 1; }
@@ -77,6 +78,9 @@
   bool is_type() const                      { return true; }
   bool is_classless() const                 { return is_primitive_type(); }
 
+  virtual ciType*     unwrap()              { return this; }
+  virtual bool is_never_null() const        { return false; }
+
   const char* name();
   virtual void print_name_on(outputStream* st);
   void print_name() {
@@ -112,4 +116,38 @@
   static ciReturnAddress* make(int bci);
 };
 
+// ciWrapper
+//
+// This class wraps another type to carry additional information like nullability.
+// Should only be instantiated and used by ciTypeFlow and ciSignature.
+class ciWrapper : public ciType {
+  CI_PACKAGE_ACCESS
+
+private:
+  ciType* _type;
+  bool _never_null;
+
+  ciWrapper(ciType* type, bool never_null) : ciType(type->basic_type()) {
+    assert(type->is_valuetype(), "should only be used for value types");
+    _type = type;
+    _never_null = never_null;
+  }
+
+  const char* type_string() { return "ciWrapper"; }
+
+  void print_impl(outputStream* st) { _type->print_impl(st); }
+
+public:
+  bool equals(ciMetadata* obj) const {
+    return obj->is_wrapper() &&
+           obj->as_wrapper()->unwrap()->equals(_type) &&
+           obj->as_wrapper()->is_never_null() == _never_null;
+  }
+
+  bool    is_wrapper() const { return true; }
+
+  ciType*     unwrap()       { return _type; }
+  bool is_never_null() const { return _never_null; }
+};
+
 #endif // SHARE_CI_CITYPE_HPP