zArray.inline.hpp

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#ifndef SHARE_GC_Z_ZARRAY_INLINE_HPP
#define SHARE_GC_Z_ZARRAY_INLINE_HPP

#include "gc/z/zArray.hpp"

#include "runtime/atomic.hpp"

template <typename T, bool Parallel>
inline bool ZArrayIteratorImpl<T, Parallel>::next_serial(T* elem) {
  if (_next == _end) {
    return false;
  }

  *elem = *_next;
  _next++;

  return true;
}

template <typename T, bool Parallel>
inline bool ZArrayIteratorImpl<T, Parallel>::next_parallel(T* elem) {
  const T* old_next = Atomic::load(&_next);

  for (;;) {
    if (old_next == _end) {
      return false;
    }

    const T* const new_next = old_next + 1;
    const T* const prev_next = Atomic::cmpxchg(&_next, old_next, new_next);
    if (prev_next == old_next) {
      *elem = *old_next;
      return true;
    }

    old_next = prev_next;
  }
}

template <typename T, bool Parallel>
inline ZArrayIteratorImpl<T, Parallel>::ZArrayIteratorImpl(const T* array, size_t length) :
    _next(array),
    _end(array + length) {}

template <typename T, bool Parallel>
inline ZArrayIteratorImpl<T, Parallel>::ZArrayIteratorImpl(const ZArray<T>* array) :
    ZArrayIteratorImpl<T, Parallel>(array->is_empty() ? NULL : array->adr_at(0), array->length()) {}

template <typename T, bool Parallel>
inline bool ZArrayIteratorImpl<T, Parallel>::next(T* elem) {
  if (Parallel) {
    return next_parallel(elem);
  } else {
    return next_serial(elem);
  }
}

#endif // SHARE_GC_Z_ZARRAY_INLINE_HPP