/*

 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * 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).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#ifndef SHARE_VM_GC_G1_G1CODEROOTSETTABLE_HPP

#define SHARE_VM_GC_G1_G1CODEROOTSETTABLE_HPP

#include "utilities/hashtable.hpp"

class nmethod;

class G1CodeRootSetTable : public Hashtable<nmethod*, mtGC> {

  friend class G1CodeRootSetTest;

  typedef HashtableEntry<nmethod*, mtGC> Entry;

  static G1CodeRootSetTable* volatile _purge_list;

  G1CodeRootSetTable* _purge_next;

  unsigned int compute_hash(nmethod* nm) {

    uintptr_t hash = (uintptr_t)nm;

    return hash ^ (hash >> 7); // code heap blocks are 128byte aligned

  }

  void remove_entry(Entry* e, Entry* previous);

  Entry* new_entry(nmethod* nm);

 public:

  G1CodeRootSetTable(int size) : Hashtable<nmethod*, mtGC>(size, sizeof(Entry)), _purge_next(NULL) {}

  ~G1CodeRootSetTable();

  // Needs to be protected by locks

  bool add(nmethod* nm);

  bool remove(nmethod* nm);

  // Can be called without locking

  bool contains(nmethod* nm);

  int entry_size() const { return BasicHashtable<mtGC>::entry_size(); }

  void copy_to(G1CodeRootSetTable* new_table);

  void nmethods_do(CodeBlobClosure* blk);

  template<typename CB>

  int remove_if(CB& should_remove);

  static void purge_list_append(G1CodeRootSetTable* tbl);

  static void purge();

  static size_t static_mem_size() {

    return sizeof(_purge_list);

  }

  size_t mem_size();

};

#endif /* SHARE_VM_GC_G1_G1CODEROOTSETTABLE_HPP */