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#ifndef SHARE_GC_G1_G1PARSCANTHREADSTATE_HPP
#define SHARE_GC_G1_G1PARSCANTHREADSTATE_HPP

#include "gc/g1/g1CollectedHeap.hpp"
#include "gc/g1/g1OopClosures.hpp"
#include "gc/g1/g1RedirtyCardsQueue.hpp"
#include "gc/g1/g1YoungGCAllocationFailureInjector.hpp"
#include "gc/shared/ageTable.hpp"
#include "gc/shared/copyFailedInfo.hpp"
#include "gc/shared/gc_globals.hpp"
#include "gc/shared/partialArraySplitter.hpp"
#include "gc/shared/partialArrayState.hpp"
#include "gc/shared/stringdedup/stringDedup.hpp"
#include "gc/shared/taskqueue.hpp"
#include "memory/allocation.hpp"
#include "oops/oop.hpp"
#include "utilities/ticks.hpp"

class G1CardTable;
class G1CollectionSet;
class G1EvacFailureRegions;
class G1EvacuationRootClosures;
class G1OopStarChunkedList;
class G1PLABAllocator;
class G1HeapRegion;
class outputStream;

class G1ParScanThreadState : public CHeapObj<mtGC> {
  G1CollectedHeap* _g1h;
  G1ScannerTasksQueue* _task_queue;
  G1RedirtyCardsLocalQueueSet _rdc_local_qset;
  G1CardTable* _ct;
  G1EvacuationRootClosures* _closures;

  G1PLABAllocator* _plab_allocator;

  AgeTable _age_table;
  // Local tenuring threshold.
  uint _tenuring_threshold;
  G1ScanEvacuatedObjClosure _scanner;

  uint _worker_id;

  // Remember the last enqueued card to avoid enqueuing the same card over and over;
  // since we only ever scan a card once, this is sufficient.
  size_t _last_enqueued_card;

  // Upper and lower threshold to start and end work queue draining.
  uint const _stack_trim_upper_threshold;
  uint const _stack_trim_lower_threshold;

  Tickspan _trim_ticks;
  // Map from young-age-index (0 == not young, 1 is youngest) to
  // surviving words. base is what we get back from the malloc call
  size_t* _surviving_young_words_base;
  // this points into the array, as we use the first few entries for padding
  size_t* _surviving_young_words;
  // Number of elements in the array above.
  size_t _surviving_words_length;
  // Indicates whether in the last generation (old) there is no more space
  // available for allocation.
  bool _old_gen_is_full;
  PartialArraySplitter _partial_array_splitter;
  StringDedup::Requests _string_dedup_requests;

  G1CardTable* ct() { return _ct; }

  // Maximum number of optional regions at start of gc.
  size_t _max_num_optional_regions;
  G1OopStarChunkedList* _oops_into_optional_regions;

  G1NUMA* _numa;
  // Records how many object allocations happened at each node during copy to survivor.
  // Only starts recording when log of gc+heap+numa is enabled and its data is
  // transferred when flushed.
  size_t* _obj_alloc_stat;

  // Per-thread evacuation failure data structures.
  ALLOCATION_FAILURE_INJECTOR_ONLY(size_t _allocation_failure_inject_counter;)

  EvacuationFailedInfo _evacuation_failed_info;
  G1EvacFailureRegions* _evac_failure_regions;
  // Number of additional cards into evacuation failed regions enqueued into
  // the local DCQS. This is an approximation, as cards that would be added later
  // outside of evacuation failure will not be subtracted again.
  size_t _evac_failure_enqueued_cards;

  // Enqueue the card if not already in the set; this is a best-effort attempt on
  // detecting duplicates.
  template <class T> bool enqueue_if_new(T* p);
  // Enqueue the card of p into the (evacuation failed) region.
  template <class T> void enqueue_card_into_evac_fail_region(T* p, oop obj);

  bool inject_allocation_failure(uint region_idx) ALLOCATION_FAILURE_INJECTOR_RETURN_( return false; );

public:
  G1ParScanThreadState(G1CollectedHeap* g1h,
                       G1RedirtyCardsQueueSet* rdcqs,
                       uint worker_id,
                       uint num_workers,
                       G1CollectionSet* collection_set,
                       G1EvacFailureRegions* evac_failure_regions);
  virtual ~G1ParScanThreadState();

  void set_ref_discoverer(ReferenceDiscoverer* rd) { _scanner.set_ref_discoverer(rd); }

#ifdef ASSERT
  bool queue_is_empty() const { return _task_queue->is_empty(); }
#endif

  void verify_task(narrowOop* task) const NOT_DEBUG_RETURN;
  void verify_task(oop* task) const NOT_DEBUG_RETURN;
  void verify_task(PartialArrayState* task) const NOT_DEBUG_RETURN;
  void verify_task(ScannerTask task) const NOT_DEBUG_RETURN;

  void push_on_queue(ScannerTask task);

  // Apply the post barrier to the given reference field. Enqueues the card of p
  // if the barrier does not filter out the reference for some reason (e.g.
  // p and q are in the same region, p is in survivor, p is in collection set)
  // To be called during GC if nothing particular about p and obj are known.
  template <class T> void write_ref_field_post(T* p, oop obj);

  // Enqueue the card if the reference's target region's remembered set is tracked.
  // Assumes that a significant amount of pre-filtering (like done by
  // write_ref_field_post() above) has already been performed.
  template <class T> void enqueue_card_if_tracked(G1HeapRegionAttr region_attr, T* p, oop o);

  G1EvacuationRootClosures* closures() { return _closures; }
  uint worker_id() { return _worker_id; }

  size_t lab_waste_words() const;
  size_t lab_undo_waste_words() const;

  size_t evac_failure_enqueued_cards() const;

  // Pass locally gathered statistics to global state. Returns the total number of
  // HeapWords copied.
  size_t flush_stats(size_t* surviving_young_words, uint num_workers, BufferNodeList* buffer_log);

#if TASKQUEUE_STATS
  PartialArrayTaskStats* partial_array_task_stats();
#endif // TASKQUEUE_STATS

private:
  void do_partial_array(PartialArrayState* state, bool stolen);
  void start_partial_objarray(oop from, oop to);

  HeapWord* allocate_copy_slow(G1HeapRegionAttr* dest_attr,
                               Klass* klass,
                               size_t word_sz,
                               uint age,
                               uint node_index);

  void undo_allocation(G1HeapRegionAttr dest_addr,
                       HeapWord* obj_ptr,
                       size_t word_sz,
                       uint node_index);

  void update_bot_after_copying(oop obj, size_t word_sz);

  void do_iterate_object(oop const obj,
                         oop const old,
                         Klass* const klass,
                         G1HeapRegionAttr const region_attr,
                         G1HeapRegionAttr const dest_attr,
                         uint age);
  oop do_copy_to_survivor_space(G1HeapRegionAttr region_attr,
                                oop obj,
                                markWord old_mark);

  // This method is applied to the fields of the objects that have just been copied.
  template <class T> void do_oop_evac(T* p);

  void dispatch_task(ScannerTask task, bool stolen);

  // Tries to allocate word_sz in the PLAB of the next "generation" after trying to
  // allocate into dest. Previous_plab_refill_failed indicates whether previous
  // PLAB refill for the original (source) object failed.
  // Returns a non-null pointer if successful, and updates dest if required.
  // Also determines whether we should continue to try to allocate into the various
  // generations or just end trying to allocate.
  HeapWord* allocate_in_next_plab(G1HeapRegionAttr* dest,
                                  size_t word_sz,
                                  bool previous_plab_refill_failed,
                                  uint node_index);

  inline G1HeapRegionAttr next_region_attr(G1HeapRegionAttr const region_attr, markWord const m, uint& age);

  void report_promotion_event(G1HeapRegionAttr const dest_attr,
                              Klass* klass, size_t word_sz, uint age,
                              HeapWord * const obj_ptr, uint node_index) const;

  void trim_queue_to_threshold(uint threshold);

  inline bool needs_partial_trimming() const;

  // NUMA statistics related methods.
  void initialize_numa_stats();
  void flush_numa_stats();
  inline void update_numa_stats(uint node_index);

public:
  oop copy_to_survivor_space(G1HeapRegionAttr region_attr, oop obj, markWord old_mark);

  inline void trim_queue();
  inline void trim_queue_partially();
  void steal_and_trim_queue(G1ScannerTasksQueueSet *task_queues);

  Tickspan trim_ticks() const;
  void reset_trim_ticks();

  void record_evacuation_failed_region(G1HeapRegion* r, uint worker_id, bool cause_pinned);
  // An attempt to evacuate "obj" has failed; take necessary steps.
  oop handle_evacuation_failure_par(oop obj, markWord m, Klass* klass, G1HeapRegionAttr attr, size_t word_sz, bool cause_pinned);

  template <typename T>
  inline void remember_root_into_optional_region(T* p);
  template <typename T>
  inline void remember_reference_into_optional_region(T* p);

  inline G1OopStarChunkedList* oops_into_optional_region(const G1HeapRegion* hr);
};

class G1ParScanThreadStateSet : public StackObj {
  G1CollectedHeap* _g1h;
  G1CollectionSet* _collection_set;
  G1RedirtyCardsQueueSet _rdcqs;
  G1ParScanThreadState** _states;
  BufferNodeList* _rdc_buffers;
  size_t* _surviving_young_words_total;
  uint _num_workers;
  bool _flushed;
  G1EvacFailureRegions* _evac_failure_regions;

 public:
  G1ParScanThreadStateSet(G1CollectedHeap* g1h,
                          uint num_workers,
                          G1CollectionSet* collection_set,
                          G1EvacFailureRegions* evac_failure_regions);
  ~G1ParScanThreadStateSet();

  G1RedirtyCardsQueueSet* rdcqs() { return &_rdcqs; }
  BufferNodeList* rdc_buffers() { return _rdc_buffers; }

  void flush_stats();
  void record_unused_optional_region(G1HeapRegion* hr);
#if TASKQUEUE_STATS
  void print_partial_array_task_stats();
#endif // TASKQUEUE_STATS

  G1ParScanThreadState* state_for_worker(uint worker_id);
  uint num_workers() const { return _num_workers; }

  const size_t* surviving_young_words() const;
};

#endif // SHARE_GC_G1_G1PARSCANTHREADSTATE_HPP