src/share/vm/utilities/taskqueue.hpp

*** 393,403 ****
  }
  
  template<class E, MEMFLAGS F, unsigned int N>
  bool GenericTaskQueue<E, F, N>::pop_global(E& t) {
    Age oldAge = _age.get();
!   uint localBot = _bottom;
    uint n_elems = size(localBot, oldAge.top());
    if (n_elems == 0) {
      return false;
    }
  
--- 393,409 ----
  }
  
  template<class E, MEMFLAGS F, unsigned int N>
  bool GenericTaskQueue<E, F, N>::pop_global(E& t) {
    Age oldAge = _age.get();
!   // Architectures with weak memory model require a barrier here
!   // to guarantee that bottom is not older than age,
!   // which is crucial for the correctness of the algorithm.
! #if !(defined SPARC || defined IA32 || defined AMD64)
!   OrderAccess::fence();
! #endif
!   uint localBot = OrderAccess::load_acquire((volatile juint*)&_bottom);
    uint n_elems = size(localBot, oldAge.top());
    if (n_elems == 0) {
      return false;
    }
  
*** 642,652 ****
  };
  
  template<class E, MEMFLAGS F, unsigned int N> inline bool
  GenericTaskQueue<E, F, N>::push(E t) {
    uint localBot = _bottom;
!   assert((localBot >= 0) && (localBot < N), "_bottom out of range.");
    idx_t top = _age.top();
    uint dirty_n_elems = dirty_size(localBot, top);
    assert(dirty_n_elems < N, "n_elems out of range.");
    if (dirty_n_elems < max_elems()) {
      // g++ complains if the volatile result of the assignment is
--- 648,658 ----
  };
  
  template<class E, MEMFLAGS F, unsigned int N> inline bool
  GenericTaskQueue<E, F, N>::push(E t) {
    uint localBot = _bottom;
!   assert(localBot < N, "_bottom out of range.");
    idx_t top = _age.top();
    uint dirty_n_elems = dirty_size(localBot, top);
    assert(dirty_n_elems < N, "n_elems out of range.");
    if (dirty_n_elems < max_elems()) {
      // g++ complains if the volatile result of the assignment is