/*

 *

 * 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_GC_SHENANDOAH_SHENANDOAHBARRIERSET_HPP

#define SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSET_HPP

#include "gc/shared/accessBarrierSupport.hpp"

#include "gc/shared/barrierSet.hpp"

#include "gc/shenandoah/shenandoahHeap.hpp"

#include "gc/shenandoah/shenandoahSATBMarkQueueSet.hpp"

class ShenandoahBarrierSetAssembler;

class ShenandoahBarrierSet: public BarrierSet {

private:

  enum ArrayCopyStoreValMode {

    NONE,

    READ_BARRIER,

    WRITE_BARRIER

  };

  ShenandoahHeap* _heap;

  ShenandoahSATBMarkQueueSet _satb_mark_queue_set;

public:

  ShenandoahBarrierSet(ShenandoahHeap* heap);

  static ShenandoahBarrierSetAssembler* assembler();

  inline static ShenandoahBarrierSet* barrier_set() {

    return barrier_set_cast<ShenandoahBarrierSet>(BarrierSet::barrier_set());

  }

  static ShenandoahSATBMarkQueueSet& satb_mark_queue_set() {

    return barrier_set()->_satb_mark_queue_set;

  }

  void print_on(outputStream* st) const;

  bool is_a(BarrierSet::Name bsn);

  bool is_aligned(HeapWord* hw);

  void write_ref_array(HeapWord* start, size_t count);

  template <class T> void

  write_ref_array_pre_work(T* dst, size_t count);

  void write_ref_array_pre(oop* dst, size_t count, bool dest_uninitialized);

  void write_ref_array_pre(narrowOop* dst, size_t count, bool dest_uninitialized);

  // 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 new_val);

  // These are the more general virtual versions.

  void write_ref_field_pre_work(oop* field, oop new_val);

  void write_ref_field_pre_work(narrowOop* field, oop new_val);

  void write_ref_field_pre_work(void* field, oop new_val);

  void write_ref_field_work(void* v, oop o, bool release = false);

  void write_region(MemRegion mr);

  virtual void on_thread_create(Thread* thread);

  virtual void on_thread_destroy(Thread* thread);

  virtual oop read_barrier(oop src);

  static inline oop resolve_forwarded_not_null(oop p);

  static inline oop resolve_forwarded(oop p);

  virtual oop write_barrier(oop obj);

  oop write_barrier_mutator(oop obj);

  virtual oop storeval_barrier(oop obj);

  virtual void keep_alive_barrier(oop obj);

  bool obj_equals(oop obj1, oop obj2);

#ifdef CHECK_UNHANDLED_OOPS

  bool oop_equals_operator_allowed() { return !ShenandoahVerifyObjectEquals; }

#endif

  void enqueue(oop obj);

private:

  inline bool need_update_refs_barrier();

  template <class T, bool STOREVAL_WRITE_BARRIER>

  void write_ref_array_loop(HeapWord* start, size_t count);

  oop write_barrier_impl(oop obj);

  static void keep_alive_if_weak(DecoratorSet decorators, oop value) {

    assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Reference strength must be known");

    const bool on_strong_oop_ref = (decorators & ON_STRONG_OOP_REF) != 0;

    const bool peek              = (decorators & AS_NO_KEEPALIVE) != 0;

    if (!peek && !on_strong_oop_ref && value != NULL) {

      ShenandoahBarrierSet::barrier_set()->keep_alive_barrier(value);

    }

  }

  template <typename T>

  bool arraycopy_loop_1(T* src, T* dst, size_t length, Klass* bound,

                        bool checkcast, bool satb, bool disjoint, ShenandoahBarrierSet::ArrayCopyStoreValMode storeval_mode);

  template <typename T, bool CHECKCAST>

  bool arraycopy_loop_2(T* src, T* dst, size_t length, Klass* bound,

                        bool satb, bool disjoint, ShenandoahBarrierSet::ArrayCopyStoreValMode storeval_mode);

  template <typename T, bool CHECKCAST, bool SATB>

  bool arraycopy_loop_3(T* src, T* dst, size_t length, Klass* bound,

                        bool disjoint, ShenandoahBarrierSet::ArrayCopyStoreValMode storeval_mode);

  template <typename T, bool CHECKCAST, bool SATB, ShenandoahBarrierSet::ArrayCopyStoreValMode STOREVAL_MODE>

  bool arraycopy_loop(T* src, T* dst, size_t length, Klass* bound, bool disjoint);

  template <typename T, bool CHECKCAST, bool SATB, ShenandoahBarrierSet::ArrayCopyStoreValMode STOREVAL_MODE>

  bool arraycopy_element(T* cur_src, T* cur_dst, Klass* bound, Thread* thread);

public:

  // Callbacks for runtime accesses.

  template <DecoratorSet decorators, typename BarrierSetT = ShenandoahBarrierSet>

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

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

  public:

    // Primitive heap accesses. These accessors get resolved when

    // IN_HEAP is set (e.g. when using the HeapAccess API), it is

    // not an oop_* overload, and the barrier strength is AS_NORMAL.

    template <typename T>

    static T load_in_heap(T* addr) {

      ShouldNotReachHere();

      return Raw::template load<T>(addr);

    }

    template <typename T>

    static T load_in_heap_at(oop base, ptrdiff_t offset) {

      base = ShenandoahBarrierSet::resolve_forwarded(base);

      return Raw::template load_at<T>(base, offset);

    }

    template <typename T>

    static void store_in_heap(T* addr, T value) {

      ShouldNotReachHere();

      Raw::store(addr, value);

    }

    template <typename T>

    static void store_in_heap_at(oop base, ptrdiff_t offset, T value) {

      base = ShenandoahBarrierSet::barrier_set()->write_barrier(base);

      Raw::store_at(base, offset, value);

    }

    template <typename T>

    static T atomic_cmpxchg_in_heap(T new_value, T* addr, T compare_value) {

      ShouldNotReachHere();

      return Raw::atomic_cmpxchg(new_value, addr, compare_value);

    }

    template <typename T>

    static T atomic_cmpxchg_in_heap_at(T new_value, oop base, ptrdiff_t offset, T compare_value) {

      base = ShenandoahBarrierSet::barrier_set()->write_barrier(base);

      return Raw::atomic_cmpxchg_at(new_value, base, offset, compare_value);

    }

    template <typename T>

    static T atomic_xchg_in_heap(T new_value, T* addr) {

      ShouldNotReachHere();

      return Raw::atomic_xchg(new_value, addr);

    }

    template <typename T>

    static T atomic_xchg_in_heap_at(T new_value, oop base, ptrdiff_t offset) {

      base = ShenandoahBarrierSet::barrier_set()->write_barrier(base);

      return Raw::atomic_xchg_at(new_value, base, offset);

    }

    template <typename T>

    static void arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,

                                  arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,

                                  size_t length);

    // Heap oop accesses. These accessors get resolved when

    // IN_HEAP is set (e.g. when using the HeapAccess API), it is

    // an oop_* overload, and the barrier strength is AS_NORMAL.

    template <typename T>

    static oop oop_load_in_heap(T* addr) {

      // ShouldNotReachHere();

      oop value = Raw::template oop_load<oop>(addr);

      keep_alive_if_weak(decorators, value);

      return value;

    }

    static oop oop_load_in_heap_at(oop base, ptrdiff_t offset) {

      base = ShenandoahBarrierSet::resolve_forwarded(base);

      oop value = Raw::template oop_load_at<oop>(base, offset);

      keep_alive_if_weak(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset), value);

      return value;

    }

    template <typename T>

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

      ShenandoahBarrierSet::barrier_set()->write_ref_field_pre_work(addr, value);

      Raw::oop_store(addr, value);

    }

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

      base = ShenandoahBarrierSet::barrier_set()->write_barrier(base);

      value = ShenandoahBarrierSet::barrier_set()->storeval_barrier(value);

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

    }

    template <typename T>

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

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

      base = ShenandoahBarrierSet::barrier_set()->write_barrier(base);

      new_value = ShenandoahBarrierSet::barrier_set()->storeval_barrier(new_value);

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

    }

    template <typename T>

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

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

      base = ShenandoahBarrierSet::barrier_set()->write_barrier(base);

      new_value = ShenandoahBarrierSet::barrier_set()->storeval_barrier(new_value);

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

    }

    template <typename T>

    static bool oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,

                                      arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,

                                      size_t length);

    // Clone barrier support

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

    // Needed for loads on non-heap weak references

    template <typename T>

    static oop oop_load_not_in_heap(T* addr) {

      oop value = Raw::oop_load_not_in_heap(addr);

      keep_alive_if_weak(decorators, value);

      return value;

    }

    static oop resolve(oop obj) {

      return ShenandoahBarrierSet::barrier_set()->write_barrier(obj);

    }

    static bool equals(oop o1, oop o2) {

      return ShenandoahBarrierSet::barrier_set()->obj_equals(o1, o2);

    }

  };

};

template<>

struct BarrierSet::GetName<ShenandoahBarrierSet> {

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

};

template<>

struct BarrierSet::GetType<BarrierSet::ShenandoahBarrierSet> {

  typedef ::ShenandoahBarrierSet type;

};

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSET_HPP