--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/runtime/stackValue.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,116 @@
+/*
+ * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_RUNTIME_STACKVALUE_HPP
+#define SHARE_VM_RUNTIME_STACKVALUE_HPP
+
+#include "code/location.hpp"
+#include "runtime/handles.hpp"
+
+class StackValue : public ResourceObj {
+ private:
+  BasicType _type;
+  intptr_t  _i; // Blank java stack slot value
+  Handle    _o; // Java stack slot value interpreted as a Handle
+ public:
+
+  StackValue(intptr_t value) {
+    _type  = T_INT;
+    _i     = value;
+  }
+
+  StackValue(Handle value, intptr_t scalar_replaced = 0) {
+    _type    = T_OBJECT;
+    _i       = scalar_replaced;
+    _o       = value;
+    assert(_i == 0 || _o.is_null(), "not null object should not be marked as scalar replaced");
+  }
+
+  StackValue() {
+    _type   = T_CONFLICT;
+    _i      = 0;
+  }
+
+  // Only used during deopt- preserve object type.
+  StackValue(intptr_t o, BasicType t) {
+    assert(t == T_OBJECT, "should not be used");
+    _type   = t;
+    _i      = o;
+  }
+
+  Handle get_obj() const {
+    assert(type() == T_OBJECT, "type check");
+    return _o;
+  }
+
+  bool obj_is_scalar_replaced() const {
+    assert(type() == T_OBJECT, "type check");
+    return _i != 0;
+  }
+
+  void set_obj(Handle value) {
+    assert(type() == T_OBJECT, "type check");
+    _o = value;
+  }
+
+  intptr_t get_int() const {
+    assert(type() == T_INT, "type check");
+    return _i;
+  }
+
+  // For special case in deopt.
+  intptr_t get_int(BasicType t) const {
+    assert(t == T_OBJECT && type() == T_OBJECT, "type check");
+    return _i;
+  }
+
+  void set_int(intptr_t value) {
+    assert(type() == T_INT, "type check");
+    _i = value;
+  }
+
+  BasicType type() const { return  _type; }
+
+  bool equal(StackValue *value) {
+    if (_type != value->_type) return false;
+    if (_type == T_OBJECT)
+      return (_o == value->_o);
+    else {
+      assert(_type == T_INT, "sanity check");
+      // [phh] compare only low addressed portions of intptr_t slots
+      return (*(int *)&_i == *(int *)&value->_i);
+    }
+  }
+
+  static StackValue* create_stack_value(const frame* fr, const RegisterMap* reg_map, ScopeValue* sv);
+  static BasicLock*  resolve_monitor_lock(const frame* fr, Location location);
+
+#ifndef PRODUCT
+ public:
+  // Printing
+  void print_on(outputStream* st) const;
+#endif
+};
+
+#endif // SHARE_VM_RUNTIME_STACKVALUE_HPP