src/hotspot/share/gc/g1/g1CodeRootSet.hpp

/*
 * Copyright (c) 2014, 2024, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_GC_G1_G1CODEROOTSET_HPP
#define SHARE_GC_G1_G1CODEROOTSET_HPP

#include "code/codeCache.hpp"
#include "utilities/globalDefinitions.hpp"

class G1CodeRootSetHashTable;
class G1HeapRegion;
class nmethod;

// Implements storage for a set of code roots.
// This class is thread safe.
class G1CodeRootSet {
  G1CodeRootSetHashTable* _table;
  DEBUG_ONLY(mutable bool _is_iterating;)

 public:
  G1CodeRootSet();
  ~G1CodeRootSet();

  void add(nmethod* method);
  bool remove(nmethod* method);
  void bulk_remove();
  bool contains(nmethod* method);
  void clear();

  // Prepare for MT iteration. Must be called before nmethods_do.
  void reset_table_scanner();
  void nmethods_do(NMethodClosure* blk) const;

  // Remove all nmethods which no longer contain pointers into our "owner" region.
  void clean(G1HeapRegion* owner);

  bool is_empty() { return length() == 0;}

  // Length in elements
  size_t length() const;

  // Memory size in bytes taken by this set.
  size_t mem_size();
};

#endif // SHARE_GC_G1_G1CODEROOTSET_HPP