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24 
25 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP
26 #define SHARE_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP
27 
28 #include "memory/allocation.hpp"
29 #include "memory/virtualspace.hpp"
30 #include "gc/shenandoah/shenandoahHeap.hpp"
31 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
32 #include "gc/shenandoah/shenandoahPadding.hpp"
33 
34 class ShenandoahCollectionSet : public CHeapObj<mtGC> {
35   friend class ShenandoahHeap;
36 private:
37   size_t const          _map_size;
38   size_t const          _region_size_bytes_shift;
39   ReservedSpace         _map_space;
40   char* const           _cset_map;
41   // Bias cset map's base address for fast test if an oop is in cset
42   char* const           _biased_cset_map;
43 
44   ShenandoahHeap* const _heap;
45 
46   size_t                _garbage;
47   size_t                _used;
48   size_t                _region_count;
49 
50   shenandoah_padding(0);
51   volatile size_t       _current_index;
52   shenandoah_padding(1);
53 
54 public:
55   ShenandoahCollectionSet(ShenandoahHeap* heap, ReservedSpace space, char* heap_base);
56 
57   // Add region to collection set
58   void add_region(ShenandoahHeapRegion* r);
59 
60   // MT version
61   ShenandoahHeapRegion* claim_next();
62 
63   // Single-thread version
64   ShenandoahHeapRegion* next();
65 
count() const66   size_t count()  const { return _region_count; }
is_empty() const67   bool is_empty() const { return _region_count == 0; }
68 
clear_current_index()69   void clear_current_index() {
70     _current_index = 0;
71   }
72 
73   inline bool is_in(ShenandoahHeapRegion* r) const;
74   inline bool is_in(size_t region_idx)       const;
75   inline bool is_in(oop obj)                 const;
76   inline bool is_in_loc(void* loc)           const;
77 
78   void print_on(outputStream* out) const;
79 
used() const80   size_t used()      const { return _used; }
garbage() const81   size_t garbage()   const { return _garbage;   }
82   void clear();
83 
84 private:
map_address() const85   char* map_address() const {
86     return _cset_map;
87   }
biased_map_address() const88   char* biased_map_address() const {
89     return _biased_cset_map;
90   }
91 };
92 
93 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP
94