/*
 * Copyright (c) 2015, Red Hat, Inc. and/or its affiliates.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_INLINE_HPP
#define SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_INLINE_HPP

#include "gc/shenandoah/brooksPointer.hpp"
#include "gc/shenandoah/shenandoahConcurrentMark.hpp"
#include "memory/iterator.inline.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/prefetch.inline.hpp"

void ShenandoahMarkRefsClosure::do_oop(oop* p) {
  // We piggy-back reference updating to the marking tasks.
#ifdef ASSERT
  oop* old = p;
#endif
  oop obj;
  if (_update_refs) {
    obj = _heap->maybe_update_oop_ref(p);
  } else {
    obj = oopDesc::load_heap_oop(p);
  }
  assert(obj == ShenandoahBarrierSet::resolve_oop_static(obj), "need to-space object here");

#ifdef ASSERT
  if (ShenandoahTraceUpdates) {
    if (p != old)
      tty->print_cr("Update "PTR_FORMAT" => "PTR_FORMAT"  to "PTR_FORMAT" => "PTR_FORMAT, p2i(p), p2i((HeapWord*) *p), p2i(old), p2i((HeapWord*) *old));
    else
      tty->print_cr("Not updating "PTR_FORMAT" => "PTR_FORMAT"  to "PTR_FORMAT" => "PTR_FORMAT, p2i(p), p2i((HeapWord*) *p), p2i(old), p2i((HeapWord*) *old));
  }
#endif

  // NOTE: We used to assert the following here. This does not always work because
  // a concurrent Java thread could change the the field after we updated it.
  // oop obj = oopDesc::load_heap_oop(p);
  // assert(oopDesc::bs()->resolve_oop(obj) == *p, "we just updated the referrer");
  // assert(obj == NULL || ! _heap->heap_region_containing(obj)->is_dirty(), "must not point to dirty region");

  //  ShenandoahExtendedMarkObjsClosure cl(_heap->ref_processor(), _worker_id);
  //  ShenandoahMarkObjsClosure mocl(cl, _worker_id);

  if (obj != NULL) {
    if (_update_refs) {
      Prefetch::write(obj, 128);
    } else {
      Prefetch::read(obj, 128);
    }

#ifdef ASSERT
    uint region_idx  = _heap->heap_region_index_containing(obj);
    ShenandoahHeapRegion* r = _heap->heap_regions()[region_idx];
    assert(r->bottom() < (HeapWord*) obj && r->top() > (HeapWord*) obj, "object must be in region");
#endif
    if (_heap->mark_current(obj)) {
      if (ShenandoahTraceConcurrentMarking) {
        tty->print_cr("marked obj: "PTR_FORMAT, p2i((HeapWord*) obj));
      }
      bool pushed = _queue->push(obj);
      assert(pushed, "overflow queue should always succeed pushing");
    }
#ifdef ASSERT
    else {
      if (ShenandoahTraceConcurrentMarking) {
        tty->print_cr("failed to mark obj (already marked): "PTR_FORMAT, p2i((HeapWord*) obj));
      }
      assert(_heap->is_marked_current(obj), "make sure object is marked");
    }
#endif
  }
}

void ShenandoahMarkObjsClosure::do_object(oop obj) {

  assert(obj != NULL, "expect non-null object");

  assert(obj == ShenandoahBarrierSet::resolve_oop_static_not_null(obj), "expect forwarded obj in queue");

#ifdef ASSERT
  if (_heap->heap_region_containing(obj)->is_in_collection_set()) {
    tty->print_cr("trying to mark obj: "PTR_FORMAT" (%s) in dirty region: ", p2i((HeapWord*) obj), BOOL_TO_STR(_heap->is_marked_current(obj)));
    //      _heap->heap_region_containing(obj)->print();
    //      _heap->print_heap_regions();
  }
#endif
  assert(_heap->cancelled_concgc()
	 || ! _heap->heap_region_containing(obj)->is_in_collection_set(),
	 "we don't want to mark objects in from-space");
  assert(_heap->is_in(obj), "referenced objects must be in the heap. No?");
  assert(_heap->is_marked_current(obj), "only marked objects on task queue");

  // Calculate liveness of heap region containing object.
  uint region_idx  = _heap->heap_region_index_containing(obj);
#ifdef ASSERT
  ShenandoahHeapRegion* r = _heap->heap_regions()[region_idx];
  assert(r->bottom() < (HeapWord*) obj && r->top() > (HeapWord*) obj, "object must be in region");
#endif
  _live_data[region_idx] += (obj->size() + BrooksPointer::BROOKS_POINTER_OBJ_SIZE) * HeapWordSize;
  obj->oop_iterate(&_mark_refs);

}

inline bool ShenandoahConcurrentMark::try_queue(SCMObjToScanQueue* q, ShenandoahMarkObjsClosure* cl) {
  oop obj;
  if (q->pop_local(obj)) {
    assert(obj != NULL, "Can't mark null");
    cl->do_object(obj);
    return true;
  } else if (q->pop_overflow(obj)) {
    cl->do_object(obj);
    return true;
  } else {
    return false;
  }
}

inline bool ShenandoahConcurrentMark::try_to_steal(uint worker_id, ShenandoahMarkObjsClosure* cl, int *seed) {
  oop obj;
  if (task_queues()->steal(worker_id, seed, obj)) {
    cl->do_object(obj);
    return true;
  } else
    return false;
}

inline bool ShenandoahConcurrentMark:: try_draining_an_satb_buffer(uint worker_id) {
  return drain_one_satb_buffer(worker_id);
}

#endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_INLINE_HPP