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24 
25 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHCODEROOTS_HPP
26 #define SHARE_GC_SHENANDOAH_SHENANDOAHCODEROOTS_HPP
27 
28 #include "code/codeCache.hpp"
29 #include "gc/shenandoah/shenandoahSharedVariables.hpp"
30 #include "gc/shenandoah/shenandoahLock.hpp"
31 #include "gc/shenandoah/shenandoahPadding.hpp"
32 #include "memory/allocation.hpp"
33 #include "memory/iterator.hpp"
34 #include "utilities/globalDefinitions.hpp"
35 
36 class ShenandoahHeap;
37 class ShenandoahHeapRegion;
38 class ShenandoahNMethodTable;
39 class ShenandoahNMethodTableSnapshot;
40 class WorkGang;
41 
42 class ShenandoahParallelCodeHeapIterator {
43   friend class CodeCache;
44 private:
45   CodeHeap*     _heap;
46   shenandoah_padding(0);
47   volatile int  _claimed_idx;
48   volatile bool _finished;
49   shenandoah_padding(1);
50 public:
51   ShenandoahParallelCodeHeapIterator(CodeHeap* heap);
52   void parallel_blobs_do(CodeBlobClosure* f);
53 };
54 
55 class ShenandoahParallelCodeCacheIterator {
56   friend class CodeCache;
57 private:
58   ShenandoahParallelCodeHeapIterator* _iters;
59   int                       _length;
60 
61   NONCOPYABLE(ShenandoahParallelCodeCacheIterator);
62 
63 public:
64   ShenandoahParallelCodeCacheIterator(const GrowableArray<CodeHeap*>* heaps);
65   ~ShenandoahParallelCodeCacheIterator();
66   void parallel_blobs_do(CodeBlobClosure* f);
67 };
68 
69 class ShenandoahCodeRootsIterator {
70   friend class ShenandoahCodeRoots;
71 protected:
72   ShenandoahParallelCodeCacheIterator _par_iterator;
73   ShenandoahSharedFlag _seq_claimed;
74   ShenandoahNMethodTableSnapshot* _table_snapshot;
75 
76 public:
77   ShenandoahCodeRootsIterator();
78   ~ShenandoahCodeRootsIterator();
79 
80   void possibly_parallel_blobs_do(CodeBlobClosure *f);
81   void fast_parallel_blobs_do(CodeBlobClosure *f);
82 };
83 
84 class ShenandoahCodeRoots : public AllStatic {
85   friend class ShenandoahHeap;
86   friend class ShenandoahCodeRootsIterator;
87 
88 public:
89   static void initialize();
90   static void register_nmethod(nmethod* nm);
91   static void unregister_nmethod(nmethod* nm);
92   static void flush_nmethod(nmethod* nm);
93 
table()94   static ShenandoahNMethodTable* table() {
95     return _nmethod_table;
96   }
97 
98   // Concurrent nmethod unloading support
99   static void unlink(WorkGang* workers, bool unloading_occurred);
100   static void purge(WorkGang* workers);
101   static void arm_nmethods();
102   static void disarm_nmethods();
disarmed_value()103   static int  disarmed_value()         { return _disarmed_value; }
disarmed_value_address()104   static int* disarmed_value_address() { return &_disarmed_value; }
105 
106 private:
107   static ShenandoahNMethodTable* _nmethod_table;
108   static int                     _disarmed_value;
109 };
110 
111 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHCODEROOTS_HPP
112