src/share/vm/gc_implementation/g1/bufferingOopClosure.hpp

@@ -24,10 +24,11 @@
 
 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_BUFFERINGOOPCLOSURE_HPP
 #define SHARE_VM_GC_IMPLEMENTATION_G1_BUFFERINGOOPCLOSURE_HPP
 
 #include "memory/iterator.hpp"
+#include "oops/oopsHierarchy.hpp"
 #include "runtime/os.hpp"
 #include "utilities/debug.hpp"
 
 // A BufferingOops closure tries to separate out the cost of finding roots
 // from the cost of applying closures to them.  It maintains an array of

@@ -43,15 +44,19 @@
 class BufferingOopClosure: public OopClosure {
   friend class TestBufferingOopClosure;
 protected:
   static const size_t BufferLength = 1024;
 
-  // The full-sized oops are filled in from the bottom,
-  // while the narrowOops are filled in from the top.
-  void*  _buffer[BufferLength];
-  void** _oop_top;
-  void** _narrowOop_bottom;
+  // We need to know if the buffered addresses contain oops or narrowOops.
+  // We can't tag the addresses the way StarTask does, because we need to
+  // be able to handle unaligned addresses coming from oops embedded in code.
+  //
+  // The addresses for the full-sized oops are filled in from the bottom,
+  // while the addresses for the narrowOops are filled in from the top.
+  OopOrNarrowOopStar  _buffer[BufferLength];
+  OopOrNarrowOopStar* _oop_top;
+  OopOrNarrowOopStar* _narrowOop_bottom;
 
   OopClosure* _oc;
   double      _closure_app_seconds;
 
 

@@ -63,19 +68,19 @@
     return _narrowOop_bottom < _oop_top;
   }
 
   // Process addresses containing full-sized oops.
   void process_oops() {
-    for (void** curr = _buffer; curr < _oop_top; ++curr) {
+    for (OopOrNarrowOopStar* curr = _buffer; curr < _oop_top; ++curr) {
       _oc->do_oop((oop*)(*curr));
     }
     _oop_top = _buffer;
   }
 
   // Process addresses containing narrow oops.
   void process_narrowOops() {
-    for (void** curr = _buffer + BufferLength - 1; curr > _narrowOop_bottom; --curr) {
+    for (OopOrNarrowOopStar* curr = _buffer + BufferLength - 1; curr > _narrowOop_bottom; --curr) {
       _oc->do_oop((narrowOop*)(*curr));
     }
     _narrowOop_bottom = _buffer + BufferLength - 1;
   }
 

@@ -96,17 +101,17 @@
     }
   }
 
   void add_narrowOop(narrowOop* p) {
     assert(!is_buffer_full(), "Buffer should not be full");
-    *_narrowOop_bottom = (void*)p;
+    *_narrowOop_bottom = (OopOrNarrowOopStar)p;
     _narrowOop_bottom--;
   }
 
   void add_oop(oop* p) {
     assert(!is_buffer_full(), "Buffer should not be full");
-    *_oop_top = (void*)p;
+    *_oop_top = (OopOrNarrowOopStar)p;
     _oop_top++;
   }
 
 public:
   virtual void do_oop(narrowOop* p) {