/*

 * Copyright (c) 2000, 2018, 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_SHARED_MODREFBARRIERSET_HPP

#define SHARE_VM_GC_SHARED_MODREFBARRIERSET_HPP

#include "gc/shared/barrierSet.hpp"

#include "memory/memRegion.hpp"

class Klass;

class ModRefBarrierSet: public BarrierSet {

protected:

  ModRefBarrierSet(BarrierSetAssembler* barrier_set_assembler,

                   BarrierSetC1* barrier_set_c1,

                   const BarrierSet::FakeRtti& fake_rtti)

    : BarrierSet(barrier_set_assembler,

                 barrier_set_c1,

                 fake_rtti.add_tag(BarrierSet::ModRef)) { }

  ~ModRefBarrierSet() { }

public:

  template <DecoratorSet decorators, typename T>

  inline void write_ref_field_pre(T* addr) {}

  template <DecoratorSet decorators, typename T>

  inline void write_ref_field_post(T *addr, oop new_value) {}

  // Causes all refs in "mr" to be assumed to be modified.

  virtual void invalidate(MemRegion mr) = 0;

  virtual void write_region(MemRegion mr) = 0;

  // Operations on arrays, or general regions (e.g., for "clone") may be

  // optimized by some barriers.

  // Below length is the # array elements being written

  virtual void write_ref_array_pre(oop* dst, size_t length,

                                   bool dest_uninitialized = false) {}

  virtual void write_ref_array_pre(narrowOop* dst, size_t length,

                                   bool dest_uninitialized = false) {}

  // Below count is the # array elements being written, starting

  // at the address "start", which may not necessarily be HeapWord-aligned

  inline void write_ref_array(HeapWord* start, size_t count);

 protected:

  virtual void write_ref_array_work(MemRegion mr) = 0;

 public:

  // The ModRef abstraction introduces pre and post barriers

  template <DecoratorSet decorators, typename BarrierSetT>

  class AccessBarrier: public BarrierSet::AccessBarrier<decorators, BarrierSetT> {

    typedef BarrierSet::AccessBarrier<decorators, BarrierSetT> Raw;

  public:

    template <typename T>

    static void oop_store_in_heap(T* addr, oop value);

    template <typename T>

    static oop oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value);

    template <typename T>

    static oop oop_atomic_xchg_in_heap(oop new_value, T* addr);

    template <typename T>

    static bool oop_arraycopy_in_heap(arrayOop src_obj, arrayOop dst_obj, T* src, T* dst, size_t length);

    static void clone_in_heap(oop src, oop dst, size_t size);

    static void oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) {

      oop_store_in_heap(AccessInternal::oop_field_addr<decorators>(base, offset), value);

    }

    static oop oop_atomic_xchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset) {

      return oop_atomic_xchg_in_heap(new_value, AccessInternal::oop_field_addr<decorators>(base, offset));

    }

    static oop oop_atomic_cmpxchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value) {

      return oop_atomic_cmpxchg_in_heap(new_value, AccessInternal::oop_field_addr<decorators>(base, offset), compare_value);

    }

  };

};

template<>

struct BarrierSet::GetName<ModRefBarrierSet> {

  static const BarrierSet::Name value = BarrierSet::ModRef;

};

#endif // SHARE_VM_GC_SHARED_MODREFBARRIERSET_HPP