--- old/src/hotspot/share/opto/memnode.hpp	2019-03-11 14:26:50.262354545 +0100
+++ new/src/hotspot/share/opto/memnode.hpp	2019-03-11 14:26:50.050354548 +0100
@@ -1095,9 +1095,11 @@
 class ClearArrayNode: public Node {
 private:
   bool _is_large;
+  bool _word_copy_only;
 public:
-  ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base, bool is_large)
-    : Node(ctrl,arymem,word_cnt,base), _is_large(is_large) {
+  ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base, Node* val, bool is_large)
+    : Node(ctrl, arymem, word_cnt, base, val), _is_large(is_large),
+      _word_copy_only(val->bottom_type()->isa_long() && (!val->bottom_type()->is_long()->is_con() || val->bottom_type()->is_long()->get_con() != 0)) {
     init_class_id(Class_ClearArray);
   }
   virtual int         Opcode() const;
@@ -1109,20 +1111,26 @@
   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
   virtual uint match_edge(uint idx) const;
   bool is_large() const { return _is_large; }
+  bool word_copy_only() const { return _word_copy_only; }
 
   // Clear the given area of an object or array.
   // The start offset must always be aligned mod BytesPerInt.
   // The end offset must always be aligned mod BytesPerLong.
   // Return the new memory.
   static Node* clear_memory(Node* control, Node* mem, Node* dest,
+                            Node* val,
+                            Node* raw_val,
                             intptr_t start_offset,
                             intptr_t end_offset,
                             PhaseGVN* phase);
   static Node* clear_memory(Node* control, Node* mem, Node* dest,
+                            Node* val,
+                            Node* raw_val,
                             intptr_t start_offset,
                             Node* end_offset,
                             PhaseGVN* phase);
   static Node* clear_memory(Node* control, Node* mem, Node* dest,
+                            Node* raw_val,
                             Node* start_offset,
                             Node* end_offset,
                             PhaseGVN* phase);
@@ -1173,7 +1181,7 @@
   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
   virtual uint match_edge(uint idx) const { return 0; }
   virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
-  virtual Node *match( const ProjNode *proj, const Matcher *m );
+  virtual Node *match(const ProjNode *proj, const Matcher *m, const RegMask* mask);
   // Factory method.  Builds a wide or narrow membar.
   // Optional 'precedent' becomes an extra edge if not null.
   static MemBarNode* make(Compile* C, int opcode,
@@ -1305,7 +1313,7 @@
   enum {
     Incomplete    = 0,
     Complete      = 1,
-    WithArraycopy = 2
+    WithArraycopy = 2,
   };
   int _is_complete;