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24 
25 #ifndef SHARE_VM_GC_G1_G1REMSETTRACKINGPOLICY_HPP
26 #define SHARE_VM_GC_G1_G1REMSETTRACKINGPOLICY_HPP
27 
28 #include "gc/g1/heapRegion.hpp"
29 #include "gc/g1/heapRegionType.hpp"
30 #include "memory/allocation.hpp"
31 
32 // The remembered set tracking policy determines for a given region the state of
33 // the remembered set, ie. when it should be tracked, and if/when the remembered
34 // set is complete.
35 class G1RemSetTrackingPolicy : public CHeapObj<mtGC> {
36 public:
37   // Do we need to scan the given region to get all outgoing references for remembered
38   // set rebuild?
39   bool needs_scan_for_rebuild(HeapRegion* r) const;
40   // Update remembered set tracking state at allocation of the region. May be
41   // called at any time. The caller makes sure that the changes to the remembered
42   // set state are visible to other threads.
43   void update_at_allocate(HeapRegion* r);
44   // Update remembered set tracking state for humongous regions before we are going to
45   // rebuild remembered sets. Called at safepoint in the remark pause.
46   bool update_humongous_before_rebuild(HeapRegion* r, bool is_live);
47   // Update remembered set tracking state before we are going to rebuild remembered
48   // sets. Called at safepoint in the remark pause.
49   bool update_before_rebuild(HeapRegion* r, size_t live_bytes);
50   // Update remembered set tracking state after rebuild is complete, i.e. the cleanup
51   // pause. Called at safepoint.
52   void update_after_rebuild(HeapRegion* r);
53   // Update remembered set tracking state when the region is freed.
54   void update_at_free(HeapRegion* r);
55 };
56 
57 #endif /* SHARE_VM_GC_G1_G1REMSETTRACKINGPOLICY_HPP */
58 
59