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

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 *

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 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

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 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

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#ifndef SHARE_VM_GC_G1_G1OOPCLOSURES_INLINE_HPP

#define SHARE_VM_GC_G1_G1OOPCLOSURES_INLINE_HPP

#include "gc/g1/g1CollectedHeap.hpp"

#include "gc/g1/g1ConcurrentMark.inline.hpp"

#include "gc/g1/g1OopClosures.hpp"

#include "gc/g1/g1ParScanThreadState.inline.hpp"

#include "gc/g1/g1RemSet.hpp"

#include "gc/g1/heapRegion.inline.hpp"

#include "gc/g1/heapRegionRemSet.hpp"

#include "memory/iterator.inline.hpp"

#include "oops/access.inline.hpp"

#include "oops/compressedOops.inline.hpp"

#include "oops/oopsHierarchy.hpp"

#include "runtime/prefetch.inline.hpp"

template <class T>

inline void G1ScanClosureBase::prefetch_and_push(T* p, const oop obj) {

  // We're not going to even bother checking whether the object is

  // already forwarded or not, as this usually causes an immediate

  // stall. We'll try to prefetch the object (for write, given that

  // we might need to install the forwarding reference) and we'll

  // get back to it when pop it from the queue

  Prefetch::write(obj->mark_addr(), 0);

  Prefetch::read(obj->mark_addr(), (HeapWordSize*2));

  // slightly paranoid test; I'm trying to catch potential

  // problems before we go into push_on_queue to know where the

  // problem is coming from

  assert((obj == RawAccess<>::oop_load(p)) ||

         (obj->is_forwarded() &&

         obj->forwardee() == RawAccess<>::oop_load(p)),

         "p should still be pointing to obj or to its forwardee");

  _par_scan_state->push_on_queue(p);

}

template <class T>

inline void G1ScanClosureBase::handle_non_cset_obj_common(InCSetState const state, T* p, oop const obj) {

  if (state.is_humongous()) {

    _g1->set_humongous_is_live(obj);

  }

}

template <class T>

inline void G1ScanEvacuatedObjClosure::do_oop_nv(T* p) {

  T heap_oop = RawAccess<>::oop_load(p);

  if (CompressedOops::is_null(heap_oop)) {

    return;

  }

  oop obj = CompressedOops::decode_not_null(heap_oop);

  const InCSetState state = _g1->in_cset_state(obj);

  if (state.is_in_cset()) {

    prefetch_and_push(p, obj);

  } else {

    if (HeapRegion::is_in_same_region(p, obj)) {

      return;

    }

    handle_non_cset_obj_common(state, p, obj);

    _par_scan_state->update_rs(_from, p, obj);

  }

}

template <class T>

inline void G1CMOopClosure::do_oop_nv(T* p) {

  _task->deal_with_reference(p);

}

template <class T>

inline void G1RootRegionScanClosure::do_oop_nv(T* p) {

  T heap_oop = RawAccess<MO_VOLATILE>::oop_load(p);

  if (CompressedOops::is_null(heap_oop)) {

    return;

  }

  oop obj = CompressedOops::decode_not_null(heap_oop);

  _cm->mark_in_next_bitmap(_worker_id, obj);

}

template <class T>

inline static void check_obj_during_refinement(T* p, oop const obj) {

#ifdef ASSERT

  G1CollectedHeap* g1 = G1CollectedHeap::heap();

  // can't do because of races

  // assert(oopDesc::is_oop_or_null(obj), "expected an oop");

  assert(check_obj_alignment(obj), "not oop aligned");

  assert(g1->is_in_reserved(obj), "must be in heap");

  HeapRegion* from = g1->heap_region_containing(p);

  assert(from != NULL, "from region must be non-NULL");

  assert(from->is_in_reserved(p) ||

         (from->is_humongous() &&

          g1->heap_region_containing(p)->is_humongous() &&

          from->humongous_start_region() == g1->heap_region_containing(p)->humongous_start_region()),

         "p " PTR_FORMAT " is not in the same region %u or part of the correct humongous object starting at region %u.",

         p2i(p), from->hrm_index(), from->humongous_start_region()->hrm_index());

#endif // ASSERT

}

template <class T>

inline void G1ConcurrentRefineOopClosure::do_oop_nv(T* p) {

  T o = RawAccess<MO_VOLATILE>::oop_load(p);

  if (CompressedOops::is_null(o)) {

    return;

  }

  oop obj = CompressedOops::decode_not_null(o);

  check_obj_during_refinement(p, obj);

  if (HeapRegion::is_in_same_region(p, obj)) {

    // Normally this closure should only be called with cross-region references.

    // But since Java threads are manipulating the references concurrently and we

    // reload the values things may have changed.

    // Also this check lets slip through references from a humongous continues region

    // to its humongous start region, as they are in different regions, and adds a

    // remembered set entry. This is benign (apart from memory usage), as we never

    // try to either evacuate or eager reclaim humonguous arrays of j.l.O.

    return;

  }

}

template <class T>

inline void G1ScanObjsDuringUpdateRSClosure::do_oop_nv(T* p) {

  T o = RawAccess<>::oop_load(p);

  if (CompressedOops::is_null(o)) {

    return;

  }

  oop obj = CompressedOops::decode_not_null(o);

  check_obj_during_refinement(p, obj);

  assert(!_g1->is_in_cset((HeapWord*)p), "Oop originates from " PTR_FORMAT " (region: %u) which is in the collection set.", p2i(p), _g1->addr_to_region((HeapWord*)p));

  const InCSetState state = _g1->in_cset_state(obj);

  if (state.is_in_cset()) {

    // Since the source is always from outside the collection set, here we implicitly know

    // that this is a cross-region reference too.

    prefetch_and_push(p, obj);

  } else {

    HeapRegion* to = _g1->heap_region_containing(obj);

    if (_from == to) {

      return;

    }

    handle_non_cset_obj_common(state, p, obj);

    to->rem_set()->add_reference(p, _worker_i);

  }

}

template <class T>

inline void G1ScanObjsDuringScanRSClosure::do_oop_nv(T* p) {

  T heap_oop = RawAccess<>::oop_load(p);

  if (CompressedOops::is_null(heap_oop)) {

    return;

  }

  oop obj = CompressedOops::decode_not_null(heap_oop);

  const InCSetState state = _g1->in_cset_state(obj);

  if (state.is_in_cset()) {

    prefetch_and_push(p, obj);

  } else {

    if (HeapRegion::is_in_same_region(p, obj)) {

      return;

    }

    handle_non_cset_obj_common(state, p, obj);

  }

}

void G1ParCopyHelper::do_cld_barrier(oop new_obj) {

  if (_g1->heap_region_containing(new_obj)->is_young()) {

    _scanned_cld->record_modified_oops();

  }

}

void G1ParCopyHelper::mark_object(oop obj) {

  assert(!_g1->heap_region_containing(obj)->in_collection_set(), "should not mark objects in the CSet");

  // We know that the object is not moving so it's safe to read its size.

  _cm->mark_in_next_bitmap(_worker_id, obj);

}

void G1ParCopyHelper::mark_forwarded_object(oop from_obj, oop to_obj) {

  assert(from_obj->is_forwarded(), "from obj should be forwarded");

  assert(from_obj->forwardee() == to_obj, "to obj should be the forwardee");

  assert(from_obj != to_obj, "should not be self-forwarded");

  assert(_g1->heap_region_containing(from_obj)->in_collection_set(), "from obj should be in the CSet");

  assert(!_g1->heap_region_containing(to_obj)->in_collection_set(), "should not mark objects in the CSet");

  // The object might be in the process of being copied by another

  // worker so we cannot trust that its to-space image is

  // well-formed. So we have to read its size from its from-space

  // image which we know should not be changing.

  _cm->mark_in_next_bitmap(_worker_id, to_obj, from_obj->size());

}

template <G1Barrier barrier, G1Mark do_mark_object>

template <class T>

void G1ParCopyClosure<barrier, do_mark_object>::do_oop_work(T* p) {

  T heap_oop = RawAccess<>::oop_load(p);

  if (CompressedOops::is_null(heap_oop)) {

    return;

  }

  oop obj = CompressedOops::decode_not_null(heap_oop);

  assert(_worker_id == _par_scan_state->worker_id(), "sanity");

  const InCSetState state = _g1->in_cset_state(obj);

  if (state.is_in_cset()) {

    oop forwardee;

    markOop m = obj->mark();

    if (m->is_marked()) {

      forwardee = (oop) m->decode_pointer();

    } else {

      forwardee = _par_scan_state->copy_to_survivor_space(state, obj, m);

    }

    assert(forwardee != NULL, "forwardee should not be NULL");

    RawAccess<>::oop_store(p, forwardee);

    if (do_mark_object != G1MarkNone && forwardee != obj) {

      // If the object is self-forwarded we don't need to explicitly

      // mark it, the evacuation failure protocol will do so.

      mark_forwarded_object(obj, forwardee);

    }

    if (barrier == G1BarrierCLD) {

      do_cld_barrier(forwardee);

    }

  } else {

    if (state.is_humongous()) {

      _g1->set_humongous_is_live(obj);

    }

    // The object is not in collection set. If we're a root scanning

    // closure during an initial mark pause then attempt to mark the object.

    if (do_mark_object == G1MarkFromRoot) {

      mark_object(obj);

    }

  }

}

#endif // SHARE_VM_GC_G1_G1OOPCLOSURES_INLINE_HPP