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 /*

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  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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  *

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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"

 // Utility routine to set an exclusive range of cards on the given

 // card liveness bitmap

 inline void ConcurrentMark::set_card_bitmap_range(BitMap* card_bm,

                                                   BitMap::idx_t start_idx,

                                                   BitMap::idx_t end_idx,

                                                   bool is_par) {

   // Set the exclusive bit range [start_idx, end_idx).

   assert((end_idx - start_idx) > 0, "at least one card");

   assert(end_idx <= card_bm->size(), "sanity");

   // Silently clip the end index

   end_idx = MIN2(end_idx, card_bm->size());

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

   // use par_at_put_range (if parallel). The range is made up of the

   // cards that are spanned by an object/mem region so 8 cards will

   // allow up to object sizes up to 4K to be handled using the loop.

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

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

       if (is_par) {

         card_bm->par_set_bit(i);

       } else {

         card_bm->set_bit(i);

       }

     }

   } else {

     // Note BitMap::par_at_put_range() and BitMap::set_range() are exclusive.

     if (is_par) {

       card_bm->par_at_put_range(start_idx, end_idx, true);

     } else {

       card_bm->set_range(start_idx, end_idx);

     }

   }

 }

 // 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;

   CardTableModRefBS* ct_bs = g1h->g1_barrier_set();

   HeapWord* start = mr.start();

   HeapWord* end = mr.end();

   size_t region_size_bytes = mr.byte_size();

   uint index = hr->hrm_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 end_idx = card_bitmap_index_for(end);

   // Note: if we're looking at the last region in heap - end

   // could be actually just beyond the end of the heap; end_idx

   // will then correspond to a (non-existent) card that is also

   // just beyond the heap.

   if (g1h->is_in_g1_reserved(end) && !ct_bs->is_card_aligned(end)) {

     // end of region is not card aligned - incremement to cover

     // all the cards spanned by the region.

     end_idx += 1;

   }

   // The card bitmap is task/worker specific => no need to use

   // the 'par' BitMap routines.

   // Set bits in the exclusive bit range [start_idx, end_idx).

   set_card_bitmap_range(task_card_bm, start_idx, end_idx, false /* is_par */);

 }

 // 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 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);

 }

 // 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;

 }

 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) {

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

         return false;

       }

       HeapWord* next_addr = MIN2(nextObject(offsetToHeapWord(start_offset)), 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);

 }

 #define check_mark(addr)                                                       \

   assert(_bmStartWord <= (addr) && (addr) < (_bmStartWord + _bmWordSize),      \

          "outside underlying space?");                                         \

   assert(G1CollectedHeap::heap()->is_in_exact(addr),                           \

          err_msg("Trying to access not available bitmap " PTR_FORMAT           \

                  " corresponding to " PTR_FORMAT " (%u)",                      \

                  p2i(this), p2i(addr), G1CollectedHeap::heap()->addr_to_region(addr)));

 inline void CMBitMap::mark(HeapWord* addr) {

   check_mark(addr);

   _bm.set_bit(heapWordToOffset(addr));

 }

 inline void CMBitMap::clear(HeapWord* addr) {

   check_mark(addr);

   _bm.clear_bit(heapWordToOffset(addr));

 }

 inline bool CMBitMap::parMark(HeapWord* addr) {

   check_mark(addr);

   return _bm.par_set_bit(heapWordToOffset(addr));

 }

 inline bool CMBitMap::parClear(HeapWord* addr) {

   check_mark(addr);

   return _bm.par_clear_bit(heapWordToOffset(addr));

 }

 #undef check_mark

 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("[%u] pushing " PTR_FORMAT, _worker_id, p2i((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("[%u] task queue overflow, "

                              "moving entries to the global stack",

                              _worker_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 );

 }

 inline bool CMTask::is_below_finger(oop obj, HeapWord* global_finger) const {

   // If obj is above the global finger, then the mark bitmap scan

   // will find it later, and no push is needed.  Similarly, if we have

   // a current region and obj is between the local finger and the

   // end of the current region, then no push is needed.  The tradeoff

   // of checking both vs only checking the global finger is that the

   // local check will be more accurate and so result in fewer pushes,

   // but may also be a little slower.

   HeapWord* objAddr = (HeapWord*)obj;

   if (_finger != NULL) {

     // We have a current region.

     // Finger and region values are all NULL or all non-NULL.  We

     // use _finger to check since we immediately use its value.

     assert(_curr_region != NULL, "invariant");

     assert(_region_limit != NULL, "invariant");

     assert(_region_limit <= global_finger, "invariant");

     // True if obj is less than the local finger, or is between

     // the region limit and the global finger.

     if (objAddr < _finger) {

       return true;

     } else if (objAddr < _region_limit) {

       return false;

     } // Else check global finger.

   }

   // Check global finger.

   return objAddr < global_finger;

 }

 inline void CMTask::make_reference_grey(oop obj, HeapRegion* hr) {

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

     if (_cm->verbose_high()) {

       gclog_or_tty->print_cr("[%u] marked object " PTR_FORMAT,

                              _worker_id, p2i(obj));

     }

     // 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();

     // We only need to push a newly grey object on the mark

     // stack if it is in a section of memory the mark bitmap

     // scan has already examined.  Mark bitmap scanning

     // maintains progress "fingers" for determining that.

     //

     // 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

     // past 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 (is_below_finger(obj, global_finger)) {

       if (obj->is_typeArray()) {

         // Immediately process arrays of primitive types, rather

         // than pushing on the mark stack.  This keeps us from

         // adding humongous objects to the mark stack that might

         // be reclaimed before the entry is processed - see

         // selection of candidates for eager reclaim of humongous

         // objects.  The cost of the additional type test is

         // mitigated by avoiding a trip through the mark stack,

         // by only doing a bookkeeping update and avoiding the

         // actual scan of the object - a typeArray contains no

         // references, and the metadata is built-in.

         process_grey_object<false>(obj);

       } else {

         if (_cm->verbose_high()) {

           gclog_or_tty->print_cr("[%u] below a finger (local: " PTR_FORMAT

                                  ", global: " PTR_FORMAT ") pushing "

                                  PTR_FORMAT " on mark stack",

                                  _worker_id, p2i(_finger),

                                  p2i(global_finger), p2i(obj));

         }

         push(obj);

       }

     }

   }

 }

 inline void CMTask::deal_with_reference(oop obj) {

   if (_cm->verbose_high()) {

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

                            _worker_id, p2i((void*) obj));

   }

   increment_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)) {

         make_reference_grey(obj, hr);

       }

     }

   }

 }

 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