*** old/src/share/vm/opto/memnode.hpp	Mon May  5 08:38:56 2014
--- new/src/share/vm/opto/memnode.hpp	Mon May  5 08:38:56 2014

*** 365,381 ****
--- 365,399 ----
  };
  
  //------------------------------LoadDNode--------------------------------------
  // Load a double (64 bits) from memory
  class LoadDNode : public LoadNode {
+   virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
+   virtual uint cmp( const Node &n ) const {
+     return _require_atomic_access == ((LoadDNode&)n)._require_atomic_access
+       && LoadNode::cmp(n);
+   }
+   virtual uint size_of() const { return sizeof(*this); }
+   const bool _require_atomic_access;  // is piecewise load forbidden?
+ 
  public:
-   LoadDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t, MemOrd mo)
      : LoadNode(c, mem, adr, at, t, mo) {}
+             MemOrd mo, bool require_atomic_access = false)
+     : LoadNode(c, mem, adr, at, t, mo), _require_atomic_access(require_atomic_access) {}
    virtual int Opcode() const;
    virtual uint ideal_reg() const { return Op_RegD; }
    virtual int store_Opcode() const { return Op_StoreD; }
    virtual BasicType memory_type() const { return T_DOUBLE; }
+   bool require_atomic_access() { return _require_atomic_access; }
+   static LoadDNode* make_atomic(Compile *C, Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
+                                 const Type* rt, MemOrd mo);
+ #ifndef PRODUCT
+   virtual void dump_spec(outputStream *st) const {
+     LoadNode::dump_spec(st);
+     if (_require_atomic_access)  st->print(" Atomic!");
+   }
+ #endif
  };
  
  //------------------------------LoadD_unalignedNode----------------------------
  // Load a double from unaligned memory
  class LoadD_unalignedNode : public LoadDNode {

*** 595,609 ****
--- 613,644 ----
  };
  
  //------------------------------StoreDNode-------------------------------------
  // Store double to memory
  class StoreDNode : public StoreNode {
+   virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
+   virtual uint cmp( const Node &n ) const {
+     return _require_atomic_access == ((StoreDNode&)n)._require_atomic_access
+       && StoreNode::cmp(n);
+   }
+   virtual uint size_of() const { return sizeof(*this); }
+   const bool _require_atomic_access;  // is piecewise store forbidden?
  public:
-   StoreDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
      : StoreNode(c, mem, adr, at, val, mo) {}
+              MemOrd mo, bool require_atomic_access = false)
+     : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
    virtual int Opcode() const;
    virtual BasicType memory_type() const { return T_DOUBLE; }
+   bool require_atomic_access() { return _require_atomic_access; }
+   static StoreDNode* make_atomic(Compile *C, Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
+ #ifndef PRODUCT
+   virtual void dump_spec(outputStream *st) const {
+     StoreNode::dump_spec(st);
+     if (_require_atomic_access)  st->print(" Atomic!");
+   }
+ #endif
+ 
  };
  
  //------------------------------StorePNode-------------------------------------
  // Store pointer to memory
  class StorePNode : public StoreNode {