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 * This code is free software; you can redistribute it and/or modify it

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 * published by the Free Software Foundation.

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 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

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

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

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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#include "classfile/javaClasses.inline.hpp"

#include "gc/parallel/parMarkBitMap.hpp"

#include "gc/parallel/psCompactionManager.hpp"

#include "gc/parallel/psParallelCompact.inline.hpp"

#include "gc/shared/taskqueue.inline.hpp"

#include "oops/access.inline.hpp"

#include "oops/arrayOop.inline.hpp"

#include "oops/compressedOops.inline.hpp"

#include "oops/objArrayOop.inline.hpp"

#include "oops/oop.inline.hpp"

#include "utilities/debug.hpp"

#include "utilities/globalDefinitions.hpp"

class PCMarkAndPushClosure: public OopClosure {

private:

  ParCompactionManager* _compaction_manager;

public:

  PCMarkAndPushClosure(ParCompactionManager* cm) : _compaction_manager(cm) { }

  template <typename T> void do_oop_nv(T* p)      { _compaction_manager->mark_and_push(p); }

  virtual void do_oop(oop* p)                     { do_oop_nv(p); }

  virtual void do_oop(narrowOop* p)               { do_oop_nv(p); }

  // This closure provides its own oop verification code.

  debug_only(virtual bool should_verify_oops()    { return false; })

};

class PCIterateMarkAndPushClosure: public MetadataVisitingOopIterateClosure {

private:

  ParCompactionManager* _compaction_manager;

public:

  PCIterateMarkAndPushClosure(ParCompactionManager* cm, ReferenceProcessor* rp) : MetadataVisitingOopIterateClosure(rp), _compaction_manager(cm) { }

  template <typename T> void do_oop_nv(T* p)      { _compaction_manager->mark_and_push(p); }

  virtual void do_oop(oop* p)                     { do_oop_nv(p); }

  virtual void do_oop(narrowOop* p)               { do_oop_nv(p); }

  void do_klass_nv(Klass* k)                      { _compaction_manager->follow_klass(k); }

  void do_cld_nv(ClassLoaderData* cld)            { _compaction_manager->follow_class_loader(cld); }

  // This closure provides its own oop verification code.

  debug_only(virtual bool should_verify_oops()    { return false; })

};

inline bool ParCompactionManager::steal(int queue_num, oop& t) {

  return stack_array()->steal(queue_num, t);

}

inline bool ParCompactionManager::steal_objarray(int queue_num, ObjArrayTask& t) {

  return _objarray_queues->steal(queue_num, t);

}

inline bool ParCompactionManager::steal(int queue_num, size_t& region) {

  return region_array()->steal(queue_num, region);

}

inline void ParCompactionManager::push(oop obj) {

  _marking_stack.push(obj);

}

void ParCompactionManager::push_objarray(oop obj, size_t index)

{

  ObjArrayTask task(obj, index);

  assert(task.is_valid(), "bad ObjArrayTask");

  _objarray_stack.push(task);

}

void ParCompactionManager::push_region(size_t index)

{

#ifdef ASSERT

  const ParallelCompactData& sd = PSParallelCompact::summary_data();

  ParallelCompactData::RegionData* const region_ptr = sd.region(index);

  assert(region_ptr->claimed(), "must be claimed");

  assert(region_ptr->_pushed++ == 0, "should only be pushed once");

#endif

  region_stack()->push(index);

}

template <typename T>

inline void ParCompactionManager::mark_and_push(T* p) {

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

  if (!CompressedOops::is_null(heap_oop)) {

    oop obj = CompressedOops::decode_not_null(heap_oop);

    assert(ParallelScavengeHeap::heap()->is_in(obj), "should be in heap");

    if (mark_bitmap()->is_unmarked(obj) && PSParallelCompact::mark_obj(obj)) {

      push(obj);

    }

  }

}

inline void ParCompactionManager::follow_klass(Klass* klass) {

  oop holder = klass->class_loader_data()->holder_no_keepalive();

  mark_and_push(&holder);

}

inline void ParCompactionManager::FollowStackClosure::do_void() {

  _compaction_manager->follow_marking_stacks();

}

template <typename T>

inline void follow_array_specialized(objArrayOop obj, int index, ParCompactionManager* cm) {

  const size_t len = size_t(obj->length());

  const size_t beg_index = size_t(index);

  assert(beg_index < len || len == 0, "index too large");

  const size_t stride = MIN2(len - beg_index, (size_t)ObjArrayMarkingStride);

  const size_t end_index = beg_index + stride;

  T* const base = (T*)obj->base_raw();

  T* const beg = base + beg_index;

  T* const end = base + end_index;

  if (end_index < len) {

    cm->push_objarray(obj, end_index); // Push the continuation.

  }

  // Push the non-NULL elements of the next stride on the marking stack.

  for (T* e = beg; e < end; e++) {

    cm->mark_and_push<T>(e);

  }

}

inline void ParCompactionManager::follow_array(objArrayOop obj, int index) {

  if (UseCompressedOops) {

    follow_array_specialized<narrowOop>(obj, index, this);

  } else {

    follow_array_specialized<oop>(obj, index, this);

  }

}

inline void ParCompactionManager::update_contents(oop obj) {

  if (!obj->klass()->is_typeArray_klass()) {

    PCAdjustPointerClosure apc(this);

    obj->oop_iterate(&apc);

  }

}

inline void ParCompactionManager::follow_class_loader(ClassLoaderData* cld) {

  PCMarkAndPushClosure mark_and_push_closure(this);

  cld->oops_do(&mark_and_push_closure, true);

}

inline void ParCompactionManager::follow_contents(oop obj) {

  assert(PSParallelCompact::mark_bitmap()->is_marked(obj), "should be marked");

  if (obj->is_objArray()) {

    follow_array(objArrayOop(obj), 0);

  } else {

    PCIterateMarkAndPushClosure cl(this, PSParallelCompact::ref_processor());

    obj->oop_iterate(&cl);

  }

}