src/hotspot/share/gc/parallel/psScavenge.cpp

rev 49944 : imported patch 8201492-properly-implement-non-contiguous-reference-processing
rev 49945 : imported patch 8201492-stefanj-review

*** 58,68 ****
  #include "services/memoryService.hpp"
  #include "utilities/stack.inline.hpp"
  
  HeapWord*                  PSScavenge::_to_space_top_before_gc = NULL;
  int                        PSScavenge::_consecutive_skipped_scavenges = 0;
! SpanReferenceProcessor*    PSScavenge::_ref_processor = NULL;
  PSCardTable*               PSScavenge::_card_table = NULL;
  bool                       PSScavenge::_survivor_overflow = false;
  uint                       PSScavenge::_tenuring_threshold = 0;
  HeapWord*                  PSScavenge::_young_generation_boundary = NULL;
  uintptr_t                  PSScavenge::_young_generation_boundary_compressed = 0;
--- 58,69 ----
  #include "services/memoryService.hpp"
  #include "utilities/stack.inline.hpp"
  
  HeapWord*                     PSScavenge::_to_space_top_before_gc = NULL;
  int                           PSScavenge::_consecutive_skipped_scavenges = 0;
! SpanSubjectToDiscoveryClosure PSScavenge::_span_discoverer;
! ReferenceProcessor*           PSScavenge::_ref_processor = NULL;
  PSCardTable*                  PSScavenge::_card_table = NULL;
  bool                          PSScavenge::_survivor_overflow = false;
  uint                          PSScavenge::_tenuring_threshold = 0;
  HeapWord*                     PSScavenge::_young_generation_boundary = NULL;
  uintptr_t                     PSScavenge::_young_generation_boundary_compressed = 0;
*** 764,777 ****
    assert(old_gen->reserved().end() <= young_gen->eden_space()->bottom(),
           "old above young");
    set_young_generation_boundary(young_gen->eden_space()->bottom());
  
    // Initialize ref handling object for scavenging.
!   MemRegion mr = young_gen->reserved();
! 
    _ref_processor =
!     new SpanReferenceProcessor(mr,                         // span
                                 ParallelRefProcEnabled && (ParallelGCThreads > 1), // mt processing
                                 ParallelGCThreads,          // mt processing degree
                                 true,                       // mt discovery
                                 ParallelGCThreads,          // mt discovery degree
                                 true,                       // atomic_discovery
--- 765,777 ----
    assert(old_gen->reserved().end() <= young_gen->eden_space()->bottom(),
           "old above young");
    set_young_generation_boundary(young_gen->eden_space()->bottom());
  
    // Initialize ref handling object for scavenging.
!   _span_discoverer.set_span(young_gen->reserved());
    _ref_processor =
!     new ReferenceProcessor(&_span_discoverer,          // span
                             ParallelRefProcEnabled && (ParallelGCThreads > 1), // mt processing
                             ParallelGCThreads,          // mt processing degree
                             true,                       // mt discovery
                             ParallelGCThreads,          // mt discovery degree
                             true,                       // atomic_discovery