--- old/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/gc/z/ZAddressRangeMapForPageTable.java	2018-07-19 22:49:37.734528426 +0900
+++ new/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/gc/z/ZAddressRangeMapForPageTable.java	2018-07-19 22:49:37.526527022 +0900
@@ -60,9 +60,15 @@
         return index;
     }
 
+    Address get(long index) {
+        return map().getAddressAt(index * VM.getVM().getBytesPerLong());
+    }
+
     Address get(Address addr) {
-        long index = index_for_addr(addr);
+        return get(index_for_addr(addr));
+    }
 
-        return map().getAddressAt(index * VM.getVM().getBytesPerLong());
+    long size() {
+        return ZGlobals.ZAddressOffsetMax >>> ZGlobals.ZPageSizeMinShift;
     }
 }