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 * accompanied this code).

 *

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#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARK_INLINE_HPP

#define SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARK_INLINE_HPP

#include "gc_implementation/g1/concurrentMark.hpp"

#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"

// Returns the index in the liveness accounting card bitmap

// for the given address

inline BitMap::idx_t ConcurrentMark::card_bitmap_index_for(HeapWord* addr) {

  // Below, the term "card num" means the result of shifting an address

  // by the card shift -- address 0 corresponds to card number 0.  One

  // must subtract the card num of the bottom of the heap to obtain a

  // card table index.

  intptr_t card_num = intptr_t(uintptr_t(addr) >> CardTableModRefBS::card_shift);

  return card_num - heap_bottom_card_num();

}

// Counts the given memory region in the given task/worker

// counting data structures.

inline void ConcurrentMark::count_region(MemRegion mr, HeapRegion* hr,

                                         size_t* marked_bytes_array,

                                         BitMap* task_card_bm) {

  G1CollectedHeap* g1h = _g1h;

  HeapWord* start = mr.start();

  HeapWord* last = mr.last();

  size_t region_size_bytes = mr.byte_size();

  size_t index = hr->hrs_index();

  assert(!hr->continuesHumongous(), "should not be HC region");

  assert(hr == g1h->heap_region_containing(start), "sanity");

  assert(hr == g1h->heap_region_containing(mr.last()), "sanity");

  assert(marked_bytes_array != NULL, "pre-condition");

  assert(task_card_bm != NULL, "pre-condition");

  // Add to the task local marked bytes for this region.

  marked_bytes_array[index] += region_size_bytes;

  BitMap::idx_t start_idx = card_bitmap_index_for(start);

  BitMap::idx_t last_idx = card_bitmap_index_for(last);

  // The card bitmap is task/worker specific => no need to use 'par' routines.

  // Set bits in the inclusive bit range [start_idx, last_idx].

  //

  // For small ranges use a simple loop; otherwise use set_range

  // The range are the cards that are spanned by the object/region

  // so 8 cards will allow objects/regions up to 4K to be handled

  // using the loop.

  if ((last_idx - start_idx) <= 8) {

    for (BitMap::idx_t i = start_idx; i <= last_idx; i += 1) {

     task_card_bm->set_bit(i);

    }

  } else {

    assert(last_idx < task_card_bm->size(), "sanity");

    // Note: BitMap::set_range() is exclusive.

    task_card_bm->set_range(start_idx, last_idx+1);

  }

}

// Counts the given memory region in the task/worker counting

// data structures for the given worker id.

inline void ConcurrentMark::count_region(MemRegion mr,

                                         HeapRegion* hr,

                                         uint worker_id) {

  size_t* marked_bytes_array = count_marked_bytes_array_for(worker_id);

  BitMap* task_card_bm = count_card_bitmap_for(worker_id);

  count_region(mr, hr, marked_bytes_array, task_card_bm);

}

// Counts the given memory region, which may be a single object, in the

// task/worker counting data structures for the given worker id.

inline void ConcurrentMark::count_region(MemRegion mr, uint worker_id) {

  HeapWord* addr = mr.start();

  HeapRegion* hr = _g1h->heap_region_containing_raw(addr);

  count_region(mr, hr, worker_id);

}

// Counts the given object in the given task/worker counting data structures.

inline void ConcurrentMark::count_object(oop obj,

                                         HeapRegion* hr,

                                         size_t* marked_bytes_array,

                                         BitMap* task_card_bm) {

  MemRegion mr((HeapWord*)obj, obj->size());

  count_region(mr, hr, marked_bytes_array, task_card_bm);

}

// Counts the given object in the task/worker counting data

// structures for the given worker id.

inline void ConcurrentMark::count_object(oop obj,

                                         HeapRegion* hr,

                                         uint worker_id) {

  size_t* marked_bytes_array = count_marked_bytes_array_for(worker_id);

  BitMap* task_card_bm = count_card_bitmap_for(worker_id);

  HeapWord* addr = (HeapWord*) obj;

  count_object(obj, hr, marked_bytes_array, task_card_bm);

}

// Attempts to mark the given object and, if successful, counts

// the object in the given task/worker counting structures.

inline bool ConcurrentMark::par_mark_and_count(oop obj,

                                               HeapRegion* hr,

                                               size_t* marked_bytes_array,

                                               BitMap* task_card_bm) {

  HeapWord* addr = (HeapWord*)obj;

  if (_nextMarkBitMap->parMark(addr)) {

    // Update the task specific count data for the object.

    count_object(obj, hr, marked_bytes_array, task_card_bm);

    return true;

  }

  return false;

}

// Attempts to mark the given object and, if successful, counts

// the object in the task/worker counting structures for the

// given worker id.

inline bool ConcurrentMark::par_mark_and_count(oop obj,

                                               size_t word_size,

                                               HeapRegion* hr,

                                               uint worker_id) {

  HeapWord* addr = (HeapWord*)obj;

  if (_nextMarkBitMap->parMark(addr)) {

    MemRegion mr(addr, word_size);

    count_region(mr, hr, worker_id);

    return true;

  }

  return false;

}

// Attempts to mark the given object and, if successful, counts

// the object in the task/worker counting structures for the

// given worker id.

inline bool ConcurrentMark::par_mark_and_count(oop obj,

                                               HeapRegion* hr,

                                               uint worker_id) {

  HeapWord* addr = (HeapWord*)obj;

  if (_nextMarkBitMap->parMark(addr)) {

    // Update the task specific count data for the object.

    count_object(obj, hr, worker_id);

    return true;

  }

  return false;

}

// As above - but we don't know the heap region containing the

// object and so have to supply it.

inline bool ConcurrentMark::par_mark_and_count(oop obj, uint worker_id) {

  HeapWord* addr = (HeapWord*)obj;

  HeapRegion* hr = _g1h->heap_region_containing_raw(addr);

  return par_mark_and_count(obj, hr, worker_id);

}

// Similar to the above routine but we already know the size, in words, of

// the object that we wish to mark/count

inline bool ConcurrentMark::par_mark_and_count(oop obj,

                                               size_t word_size,

                                               uint worker_id) {

  HeapWord* addr = (HeapWord*)obj;

  if (_nextMarkBitMap->parMark(addr)) {

    // Update the task specific count data for the object.

    MemRegion mr(addr, word_size);

    count_region(mr, worker_id);

    return true;

  }

  return false;

}

// Unconditionally mark the given object, and unconditinally count

// the object in the counting structures for worker id 0.

// Should *not* be called from parallel code.

inline bool ConcurrentMark::mark_and_count(oop obj, HeapRegion* hr) {

  HeapWord* addr = (HeapWord*)obj;

  _nextMarkBitMap->mark(addr);

  // Update the task specific count data for the object.

  count_object(obj, hr, 0 /* worker_id */);

  return true;

}

// As above - but we don't have the heap region containing the

// object, so we have to supply it.

inline bool ConcurrentMark::mark_and_count(oop obj) {

  HeapWord* addr = (HeapWord*)obj;

  HeapRegion* hr = _g1h->heap_region_containing_raw(addr);

  return mark_and_count(obj, hr);

}

inline bool CMBitMapRO::iterate(BitMapClosure* cl, MemRegion mr) {

  HeapWord* start_addr = MAX2(startWord(), mr.start());

  HeapWord* end_addr = MIN2(endWord(), mr.end());

  if (end_addr > start_addr) {

    // Right-open interval [start-offset, end-offset).

    BitMap::idx_t start_offset = heapWordToOffset(start_addr);

    BitMap::idx_t end_offset = heapWordToOffset(end_addr);

    start_offset = _bm.get_next_one_offset(start_offset, end_offset);

    while (start_offset < end_offset) {

      HeapWord* obj_addr = offsetToHeapWord(start_offset);

      oop obj = (oop) obj_addr;

      if (!cl->do_bit(start_offset)) {

        return false;

      }

      HeapWord* next_addr = MIN2(obj_addr + obj->size(), end_addr);

      BitMap::idx_t next_offset = heapWordToOffset(next_addr);

      start_offset = _bm.get_next_one_offset(next_offset, end_offset);

    }

  }

  return true;

}

inline bool CMBitMapRO::iterate(BitMapClosure* cl) {

  MemRegion mr(startWord(), sizeInWords());

  return iterate(cl, mr);

}

inline void CMTask::push(oop obj) {

  HeapWord* objAddr = (HeapWord*) obj;

  assert(_g1h->is_in_g1_reserved(objAddr), "invariant");

  assert(!_g1h->is_on_master_free_list(

              _g1h->heap_region_containing((HeapWord*) objAddr)), "invariant");

  assert(!_g1h->is_obj_ill(obj), "invariant");

  assert(_nextMarkBitMap->isMarked(objAddr), "invariant");

  if (_cm->verbose_high()) {

    gclog_or_tty->print_cr("[%d] pushing "PTR_FORMAT, _task_id, (void*) obj);

  }

  if (!_task_queue->push(obj)) {

    // The local task queue looks full. We need to push some entries

    // to the global stack.

    if (_cm->verbose_medium()) {

      gclog_or_tty->print_cr("[%d] task queue overflow, "

                             "moving entries to the global stack",

                             _task_id);

    }

    move_entries_to_global_stack();

    // this should succeed since, even if we overflow the global

    // stack, we should have definitely removed some entries from the

    // local queue. So, there must be space on it.

    bool success = _task_queue->push(obj);

    assert(success, "invariant");

  }

  statsOnly( int tmp_size = _task_queue->size();

             if (tmp_size > _local_max_size) {

               _local_max_size = tmp_size;

             }

             ++_local_pushes );

}

// This determines whether the method below will check both the local

// and global fingers when determining whether to push on the stack a

// gray object (value 1) or whether it will only check the global one

// (value 0). The tradeoffs are that the former will be a bit more

// accurate and possibly push less on the stack, but it might also be

// a little bit slower.

#define _CHECK_BOTH_FINGERS_      1

inline void CMTask::deal_with_reference(oop obj) {

  if (_cm->verbose_high()) {

    gclog_or_tty->print_cr("[%d] we're dealing with reference = "PTR_FORMAT,

                           _task_id, (void*) obj);

  }

  ++_refs_reached;

  HeapWord* objAddr = (HeapWord*) obj;

  assert(obj->is_oop_or_null(true /* ignore mark word */), "Error");

  if (_g1h->is_in_g1_reserved(objAddr)) {

    assert(obj != NULL, "null check is implicit");

    if (!_nextMarkBitMap->isMarked(objAddr)) {

      // Only get the containing region if the object is not marked on the

      // bitmap (otherwise, it's a waste of time since we won't do

      // anything with it).

      HeapRegion* hr = _g1h->heap_region_containing_raw(obj);

      if (!hr->obj_allocated_since_next_marking(obj)) {

        if (_cm->verbose_high()) {

          gclog_or_tty->print_cr("[%d] "PTR_FORMAT" is not considered marked",

                                 _task_id, (void*) obj);

        }

        // we need to mark it first

        if (_cm->par_mark_and_count(obj, hr, _marked_bytes_array, _card_bm)) {

          // No OrderAccess:store_load() is needed. It is implicit in the

          // CAS done in CMBitMap::parMark() call in the routine above.

          HeapWord* global_finger = _cm->finger();

#if _CHECK_BOTH_FINGERS_

          // we will check both the local and global fingers

          if (_finger != NULL && objAddr < _finger) {

            if (_cm->verbose_high()) {

              gclog_or_tty->print_cr("[%d] below the local finger ("PTR_FORMAT"), "

                                     "pushing it", _task_id, _finger);

            }

            push(obj);

          } else if (_curr_region != NULL && objAddr < _region_limit) {

            // do nothing

          } else if (objAddr < global_finger) {

            // Notice that the global finger might be moving forward

            // concurrently. This is not a problem. In the worst case, we

            // mark the object while it is above the global finger and, by

            // the time we read the global finger, it has moved forward

            // passed this object. In this case, the object will probably

            // be visited when a task is scanning the region and will also

            // be pushed on the stack. So, some duplicate work, but no

            // correctness problems.

            if (_cm->verbose_high()) {

              gclog_or_tty->print_cr("[%d] below the global finger "

                                     "("PTR_FORMAT"), pushing it",

                                     _task_id, global_finger);

            }

            push(obj);

          } else {

            // do nothing

          }

#else // _CHECK_BOTH_FINGERS_

          // we will only check the global finger

          if (objAddr < global_finger) {

            // see long comment above

            if (_cm->verbose_high()) {

              gclog_or_tty->print_cr("[%d] below the global finger "

                                     "("PTR_FORMAT"), pushing it",

                                     _task_id, global_finger);

            }

            push(obj);

          }

#endif // _CHECK_BOTH_FINGERS_

        }

      }

    }

  }

}

inline void ConcurrentMark::markPrev(oop p) {

  assert(!_prevMarkBitMap->isMarked((HeapWord*) p), "sanity");

  // Note we are overriding the read-only view of the prev map here, via

  // the cast.

  ((CMBitMap*)_prevMarkBitMap)->mark((HeapWord*) p);

}

inline void ConcurrentMark::grayRoot(oop obj, size_t word_size,

                                     uint worker_id, HeapRegion* hr) {

  assert(obj != NULL, "pre-condition");

  HeapWord* addr = (HeapWord*) obj;

  if (hr == NULL) {

    hr = _g1h->heap_region_containing_raw(addr);

  } else {

    assert(hr->is_in(addr), "pre-condition");

  }

  assert(hr != NULL, "sanity");

  // Given that we're looking for a region that contains an object

  // header it's impossible to get back a HC region.

  assert(!hr->continuesHumongous(), "sanity");

  // We cannot assert that word_size == obj->size() given that obj

  // might not be in a consistent state (another thread might be in

  // the process of copying it). So the best thing we can do is to

  // assert that word_size is under an upper bound which is its

  // containing region's capacity.

  assert(word_size * HeapWordSize <= hr->capacity(),

         err_msg("size: "SIZE_FORMAT" capacity: "SIZE_FORMAT" "HR_FORMAT,

                 word_size * HeapWordSize, hr->capacity(),

                 HR_FORMAT_PARAMS(hr)));

  if (addr < hr->next_top_at_mark_start()) {

    if (!_nextMarkBitMap->isMarked(addr)) {

      par_mark_and_count(obj, word_size, hr, worker_id);

    }

  }

}

#endif // SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARK_INLINE_HPP