--- old/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/gc/z/ZCollectedHeap.java	2018-01-10 17:33:38.109567017 +0100
+++ new/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/gc/z/ZCollectedHeap.java	2018-01-10 17:33:37.805556996 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2018, 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
@@ -27,6 +27,7 @@
 import java.io.PrintStream;
 
 import sun.jvm.hotspot.debugger.Address;
+import sun.jvm.hotspot.debugger.OopHandle;
 import sun.jvm.hotspot.gc.shared.CollectedHeap;
 import sun.jvm.hotspot.gc.shared.CollectedHeapName;
 import sun.jvm.hotspot.runtime.VM;
@@ -68,4 +69,27 @@
     public ZCollectedHeap(Address addr) {
         super(addr);
     }
+
+    public OopHandle oop_load_at(OopHandle handle, long offset) {
+        assert(!VM.getVM().isCompressedOopsEnabled());
+
+        Address oopAddress = handle.getAddressAt(offset);
+
+        oopAddress = ZBarrier.weak_barrier(oopAddress);
+        if (oopAddress == null) {
+            return null;
+        }
+
+        return oopAddress.addOffsetToAsOopHandle(0);
+    }
+
+    public String oopAddressDescription(OopHandle handle) {
+        Address origOop = ZOop.to_address(handle);
+        Address loadBarrieredOop = ZBarrier.weak_barrier(origOop);
+        if (!origOop.equals(loadBarrieredOop)) {
+            return origOop + " (" + loadBarrieredOop.toString() + ")";
+        } else {
+            return handle.toString();
+        }
+    }
 }