diff -r ae5b2f1dcf12 -r c3f1170908be src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp
--- a/src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp	Wed Jun 08 21:48:38 2011 -0400
+++ b/src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp	Fri Jun 10 13:16:40 2011 -0400
@@ -34,9 +34,10 @@
 
 // Inline functions for G1CollectedHeap
 
+template <class T>
 inline HeapRegion*
-G1CollectedHeap::heap_region_containing(const void* addr) const {
-  HeapRegion* hr = _hrs->addr_to_region(addr);
+G1CollectedHeap::heap_region_containing(const T addr) const {
+  HeapRegion* hr = _hrs.addr_to_region((HeapWord*) addr);
   // hr can be null if addr in perm_gen
   if (hr != NULL && hr->continuesHumongous()) {
     hr = hr->humongous_start_region();
@@ -44,19 +45,16 @@
   return hr;
 }
 
+template <class T>
 inline HeapRegion*
-G1CollectedHeap::heap_region_containing_raw(const void* addr) const {
-  assert(_g1_reserved.contains(addr), "invariant");
-  size_t index = pointer_delta(addr, _g1_reserved.start(), 1)
-                                        >> HeapRegion::LogOfHRGrainBytes;
-
-  HeapRegion* res = _hrs->at(index);
-  assert(res == _hrs->addr_to_region(addr), "sanity");
+G1CollectedHeap::heap_region_containing_raw(const T addr) const {
+  assert(_g1_reserved.contains((const void*) addr), "invariant");
+  HeapRegion* res = _hrs.addr_to_region_unsafe((HeapWord*) addr);
   return res;
 }
 
 inline bool G1CollectedHeap::obj_in_cs(oop obj) {
-  HeapRegion* r = _hrs->addr_to_region(obj);
+  HeapRegion* r = _hrs.addr_to_region((HeapWord*) obj);
   return r != NULL && r->in_collection_set();
 }