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#ifndef SHARE_VM_GC_SHARED_MODREFBARRIERSET_INLINE_HPP
#define SHARE_VM_GC_SHARED_MODREFBARRIERSET_INLINE_HPP

#include "gc/shared/modRefBarrierSet.hpp"
#include "oops/oop.hpp"

// count is number of array elements being written
void ModRefBarrierSet::write_ref_array(HeapWord* start, size_t count) {
  assert(count <= (size_t)max_intx, "count too large");
  HeapWord* end = (HeapWord*)((char*)start + (count*heapOopSize));
  // In the case of compressed oops, start and end may potentially be misaligned;
  // so we need to conservatively align the first downward (this is not
  // strictly necessary for current uses, but a case of good hygiene and,
  // if you will, aesthetics) and the second upward (this is essential for
  // current uses) to a HeapWord boundary, so we mark all cards overlapping
  // this write. If this evolves in the future to calling a
  // logging barrier of narrow oop granularity, like the pre-barrier for G1
  // (mentioned here merely by way of example), we will need to change this
  // interface, so it is "exactly precise" (if i may be allowed the adverbial
  // redundancy for emphasis) and does not include narrow oop slots not
  // included in the original write interval.
  HeapWord* aligned_start = (HeapWord*)align_size_down((uintptr_t)start, HeapWordSize);
  HeapWord* aligned_end   = (HeapWord*)align_size_up  ((uintptr_t)end,   HeapWordSize);
  // If compressed oops were not being used, these should already be aligned
  assert(UseCompressedOops || (aligned_start == start && aligned_end == end),
         "Expected heap word alignment of start and end");
  write_ref_array_region(MemRegion(aligned_start, aligned_end));
}

template <DecoratorSet decorators, typename BarrierSetT>
inline void ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
oop_store(void* addr, oop value) {
  if (!DecoratorTest<decorators>::HAS_ACCESS_ON_HEAP || DecoratorTest<decorators>::HAS_ACCESS_WEAK) {
    Basic::oop_store(addr, value);
  } else {
    BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
    bs->BarrierSetT::template write_ref_field_pre<decorators>(addr);
    Basic::oop_store(addr, value);
    bs->BarrierSetT::template write_ref_field_post<decorators>(addr, value);
  }
}

template <DecoratorSet decorators, typename BarrierSetT>
inline void ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
oop_store_at(Klass* base, ptrdiff_t offset, oop value) {
  BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
  bs->BarrierSetT::klass_update_barrier_set_pre(base, (oop*)Basic::field_addr(base, offset));
  Basic::oop_store(Basic::field_addr(base, offset), value);
  bs->BarrierSetT::klass_update_barrier_set(base, (oop*)Basic::field_addr(base, offset), value);
}

template <DecoratorSet decorators, typename BarrierSetT>
inline oop ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
oop_cas(oop new_value, void* addr, oop compare_value) {
  if (!DecoratorTest<decorators>::HAS_ACCESS_ON_HEAP || DecoratorTest<decorators>::HAS_ACCESS_WEAK) {
    return Basic::oop_cas(new_value, addr, compare_value);
  } else {
    BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
    bs->BarrierSetT::template write_ref_field_pre<decorators>(addr);
    oop result = Basic::oop_cas(new_value, addr, compare_value);
    if (result == compare_value) {
      bs->BarrierSetT::template write_ref_field_post<decorators>(addr, new_value);
    }
    return result;
  }
}

template <DecoratorSet decorators, typename BarrierSetT>
inline oop ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_swap(oop new_value, void* addr) {
  if (!DecoratorTest<decorators>::HAS_ACCESS_ON_HEAP || DecoratorTest<decorators>::HAS_ACCESS_WEAK) {
    return Basic::oop_swap(new_value, addr);
  } else {
    BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
    bs->BarrierSetT::template write_ref_field_pre<decorators>(addr);
    oop result = Basic::oop_swap(new_value, addr);
    bs->BarrierSetT::template write_ref_field_post<decorators>(addr, new_value);
    return result;
  }
}

template <DecoratorSet decorators, typename BarrierSetT>
template <typename T>
inline bool ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
oop_copy(arrayOop src_obj, arrayOop dst_obj, T* src, T* dst, size_t length) {
  BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());

  if (DecoratorTest<decorators>::HAS_DEST_COVARIANT) {
    // Optimized case
    bs->BarrierSetT::write_ref_array_pre(dst, (int)length,
                                         DecoratorTest<decorators>::HAS_DEST_NOT_INITIALIZED);
    Basic::template oop_copy<T>(src_obj, dst_obj, src, dst, length);
    bs->BarrierSetT::write_ref_array((HeapWord*)dst, length);
  } else {
    Klass* bound = bound_for_array((oop)dst_obj);
    T* from = src;
    T* end = from + length;
    for (T* p = dst; from < end; from++, p++) {
      // XXX this is going to be slow.
      T element = *from;
      // even slower now
      bool element_is_null = oopDesc::is_null(element);
      oop new_val = element_is_null ? oop(NULL)
                                    : oopDesc::decode_heap_oop_not_null(element);
      if (element_is_null || is_bounded_by(new_val, bound)) {
        bs->BarrierSetT::template write_ref_field_pre<decorators>((void*)p);
        *p = element;
      } else {
        // We must do a barrier to cover the partial copy.
        const size_t pd = pointer_delta(p, dst, (size_t)heapOopSize);
        // pointer delta is scaled to number of elements (length field in
        // objArrayOop) which we assume is 32 bit.
        assert(pd == (size_t)(int)pd, "length field overflow");
        bs->BarrierSetT::write_ref_array((HeapWord*)dst, pd);
        return false;
      }
    }
    bs->BarrierSetT::write_ref_array((HeapWord*)dst, length);
  }
  return true;
}

template <DecoratorSet decorators, typename BarrierSetT>
inline void ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::
clone(oop src, oop dst, size_t size) {
  Basic::clone(src, dst, size);
  BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set());
  bs->BarrierSetT::write_region(MemRegion((HeapWord*)(void*)dst, size));
}

#endif // SHARE_VM_GC_SHARED_MODREFBARRIERSET_INLINE_HPP