src/share/vm/gc/g1/heapRegion.hpp

rev 13047 : imported patch 8071280-specialize-heapregion-oops-on-card-seq-iterate
rev 13048 : imported patch 8071280-kim-review
rev 13049 : imported patch 8071280-kim-sangheon-review
rev 13050 : imported patch 8071280-erikh-review

@@ -249,13 +249,14 @@
 
   void report_region_type_change(G1HeapRegionTraceType::Type to);
 
   // Returns whether the given object address refers to a dead object, and either the
   // size of the object (if live) or the size of the block (if dead) in size.
-  // Performs some optimizations if is_gc_active is set.
-  template <bool is_gc_active>
-  inline bool is_obj_dead_with_size(const oop obj, G1CMBitMapRO* bitmap, size_t* size) const;
+  // May
+  // - only called with obj < top()
+  // - not called on humongous objects or archive regions
+  inline bool is_obj_dead_with_size(const oop obj, G1CMBitMapRO* prev_bitmap, size_t* size) const;
 
  protected:
   // The index of this region in the heap region sequence.
   uint  _hrm_index;
 

@@ -327,11 +328,11 @@
                                            Closure* cl,
                                            G1CollectedHeap* g1h);
 
   // Returns the block size of the given (dead, potentially having its class unloaded) object
   // starting at p extending to at most the prev TAMS using the given mark bitmap.
-  inline size_t block_size_using_bitmap(const HeapWord* p, const G1CMBitMapRO* bitmap) const;
+  inline size_t block_size_using_bitmap(const HeapWord* p, const G1CMBitMapRO* prev_bitmap) const;
  public:
   HeapRegion(uint hrm_index,
              G1BlockOffsetTable* bot,
              MemRegion mr);
 

@@ -374,16 +375,12 @@
   static void setup_heap_region_size(size_t initial_heap_size, size_t max_heap_size);
 
   // All allocated blocks are occupied by objects in a HeapRegion
   bool block_is_obj(const HeapWord* p) const;
 
-  // Returns the object size for valid block starts for potentially unloaded dead
-  // objects. Must only be called during scanning cards during GC. Expects the
-  // following preconditions:
-  // - only called on p < top()
-  // - not called on humongous objects or archive regions
-  size_t block_size_during_gc(const HeapWord* p, const G1CMBitMapRO* bitmap) const;
+  // Returns whether the given object is dead based on TAMS and bitmap.
+  bool is_obj_dead(const oop obj, const G1CMBitMapRO* prev_bitmap) const;
 
   // Returns the object size for all valid block starts
   // and the amount of unallocated words if called on top()
   size_t block_size(const HeapWord* p) const;
 

@@ -676,12 +673,12 @@
     }
   }
 
   // Iterate over the objects overlapping part of a card, applying cl
   // to all references in the region.  This is a helper for
-  // G1RemSet::refine_card, and is tightly coupled with it.
-  // mr: the memory region covered by the card, trimmed to the
+  // G1RemSet::refine_card*, and is tightly coupled with them.
+  // mr is the memory region covered by the card, trimmed to the
   // allocated space for this region.  Must not be empty.
   // This region must be old or humongous.
   // Returns true if the designated objects were successfully
   // processed, false if an unparsable part of the heap was
   // encountered; that only happens when invoked concurrently with the