--- old/src/hotspot/share/gc/g1/g1PageBasedVirtualSpace.cpp	2019-10-15 07:17:54.706090912 -0700
+++ new/src/hotspot/share/gc/g1/g1PageBasedVirtualSpace.cpp	2019-10-15 07:17:54.334090901 -0700
@@ -289,6 +289,11 @@
   return _low_boundary <= (const char*) p && (const char*) p < _high_boundary;
 }
 
+size_t G1PageBasedVirtualSpace::page_size() const {
+  assert(_page_size > 0, "Page size is not yet initialized.");
+  return _page_size;
+}
+
 #ifndef PRODUCT
 void G1PageBasedVirtualSpace::print_on(outputStream* out) {
   out->print   ("Virtual space:");