/*

 * Copyright (c) 2001, 2010, 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

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 */

#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1SATBCARDTABLEMODREFBS_HPP

#define SHARE_VM_GC_IMPLEMENTATION_G1_G1SATBCARDTABLEMODREFBS_HPP

#include "memory/cardTableModRefBS.hpp"

#include "memory/memRegion.hpp"

#include "oops/oop.inline.hpp"

#ifndef SERIALGC

class DirtyCardQueueSet;

// This barrier is specialized to use a logging barrier to support

// snapshot-at-the-beginning marking.

class G1SATBCardTableModRefBS: public CardTableModRefBSForCTRS {

private:

  // Add "pre_val" to a set of objects that may have been disconnected from the

  // pre-marking object graph.

  static void enqueue(oop pre_val);

public:

  G1SATBCardTableModRefBS(MemRegion whole_heap,

                          int max_covered_regions);

  bool is_a(BarrierSet::Name bsn) {

    return bsn == BarrierSet::G1SATBCT || CardTableModRefBS::is_a(bsn);

  }

  virtual bool has_write_ref_pre_barrier() { return true; }

  // This notes that we don't need to access any BarrierSet data

  // structures, so this can be called from a static context.

  template <class T> static void write_ref_field_pre_static(T* field, oop newVal) {

    T heap_oop = oopDesc::load_heap_oop(field);

    if (!oopDesc::is_null(heap_oop)) {

      enqueue(oopDesc::decode_heap_oop(heap_oop));

    }

  }

  // When we know the current java thread:

  template <class T> static void write_ref_field_pre_static(T* field, oop newVal,

                                                            JavaThread* jt);

  // We export this to make it available in cases where the static

  // type of the barrier set is known.  Note that it is non-virtual.

  template <class T> inline void inline_write_ref_field_pre(T* field, oop newVal) {

    write_ref_field_pre_static(field, newVal);

  }

  // These are the more general virtual versions.

  virtual void write_ref_field_pre_work(oop* field, oop new_val) {

    inline_write_ref_field_pre(field, new_val);

  }

  virtual void write_ref_field_pre_work(narrowOop* field, oop new_val) {

    inline_write_ref_field_pre(field, new_val);

  }

  virtual void write_ref_field_pre_work(void* field, oop new_val) {

    guarantee(false, "Not needed");

  }

  template <class T> void write_ref_array_pre_work(T* dst, int count);

  virtual void write_ref_array_pre(oop* dst, int count) {

    write_ref_array_pre_work(dst, count);

  }

  virtual void write_ref_array_pre(narrowOop* dst, int count) {

    write_ref_array_pre_work(dst, count);

  }

};

// Adds card-table logging to the post-barrier.

// Usual invariant: all dirty cards are logged in the DirtyCardQueueSet.

class G1SATBCardTableLoggingModRefBS: public G1SATBCardTableModRefBS {

 private:

  DirtyCardQueueSet& _dcqs;

 public:

  G1SATBCardTableLoggingModRefBS(MemRegion whole_heap,

                                 int max_covered_regions);

  bool is_a(BarrierSet::Name bsn) {

    return bsn == BarrierSet::G1SATBCTLogging ||

      G1SATBCardTableModRefBS::is_a(bsn);

  }

  void write_ref_field_work(void* field, oop new_val);

  // Can be called from static contexts.

  static void write_ref_field_static(void* field, oop new_val);

  // NB: if you do a whole-heap invalidation, the "usual invariant" defined

  // above no longer applies.

  void invalidate(MemRegion mr, bool whole_heap = false);

  void write_region_work(MemRegion mr)    { invalidate(mr); }

  void write_ref_array_work(MemRegion mr) { invalidate(mr); }

};

#endif // SERIALGC

#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1SATBCARDTABLEMODREFBS_HPP