85 // in an unfiltered buffer refer to valid objects.                                                                         
86 
87 inline bool requires_marking(const void* entry, G1CollectedHeap* heap) {                                                   
88   // Includes rejection of NULL pointers.                                                                                  
89   assert(heap->is_in_reserved(entry),                                                                                      
90          "Non-heap pointer in SATB buffer: " PTR_FORMAT, p2i(entry));                                                      
91 
92   HeapRegion* region = heap->heap_region_containing(entry);                                                                
93   assert(region != NULL, "No region for " PTR_FORMAT, p2i(entry));                                                         
94   if (entry >= region->next_top_at_mark_start()) {                                                                         
95     return false;                                                                                                          
96   }                                                                                                                        
97 
98   assert(oopDesc::is_oop(oop(entry), true /* ignore mark word */),                                                         
99          "Invalid oop in SATB buffer: " PTR_FORMAT, p2i(entry));                                                           
100 
101   return true;                                                                                                             
102 }                                                                                                                          
103 
104 inline bool retain_entry(const void* entry, G1CollectedHeap* heap) {                                                       
105   return requires_marking(entry, heap) && !heap->isMarkedNext((oop)entry);                                                 
106 }                                                                                                                          
107 
108 // This method removes entries from a SATB buffer that will not be                                                         
109 // useful to the concurrent marking threads.  Entries are retained if                                                      
110 // they require marking and are not already marked. Retained entries                                                       
111 // are compacted toward the top of the buffer.                                                                             
112 
113 void SATBMarkQueue::filter() {                                                                                             
114   G1CollectedHeap* g1h = G1CollectedHeap::heap();                                                                          
115   void** buf = _buf;                                                                                                       
116 
117   if (buf == NULL) {                                                                                                       
118     // nothing to do                                                                                                       
119     return;                                                                                                                
120   }                                                                                                                        
121 
122   // Two-fingered compaction toward the end.                                                                               
123   void** src = &buf[index()];                                                                                              
124   void** dst = &buf[capacity()];                                                                                           

85 // in an unfiltered buffer refer to valid objects.
86 
87 inline bool requires_marking(const void* entry, G1CollectedHeap* heap) {
88   // Includes rejection of NULL pointers.
89   assert(heap->is_in_reserved(entry),
90          "Non-heap pointer in SATB buffer: " PTR_FORMAT, p2i(entry));
91 
92   HeapRegion* region = heap->heap_region_containing(entry);
93   assert(region != NULL, "No region for " PTR_FORMAT, p2i(entry));
94   if (entry >= region->next_top_at_mark_start()) {
95     return false;
96   }
97 
98   assert(oopDesc::is_oop(oop(entry), true /* ignore mark word */),
99          "Invalid oop in SATB buffer: " PTR_FORMAT, p2i(entry));
100 
101   return true;
102 }
103 
104 inline bool retain_entry(const void* entry, G1CollectedHeap* heap) {
105   return requires_marking(entry, heap) && !heap->is_marked_next((oop)entry);
106 }
107 
108 // This method removes entries from a SATB buffer that will not be
109 // useful to the concurrent marking threads.  Entries are retained if
110 // they require marking and are not already marked. Retained entries
111 // are compacted toward the top of the buffer.
112 
113 void SATBMarkQueue::filter() {
114   G1CollectedHeap* g1h = G1CollectedHeap::heap();
115   void** buf = _buf;
116 
117   if (buf == NULL) {
118     // nothing to do
119     return;
120   }
121 
122   // Two-fingered compaction toward the end.
123   void** src = &buf[index()];
124   void** dst = &buf[capacity()];