/*

 * Copyright (c) 2017, 2018 Oracle and/or its affiliates. All rights reserved.

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

 *

 * 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_G1_G1MARKSTACK_INLINE_HPP

#define SHARE_VM_GC_G1_G1MARKSTACK_INLINE_HPP

#include "gc/g1/g1Allocator.inline.hpp"

#include "gc/g1/g1ConcurrentMarkBitMap.inline.hpp"

#include "gc/g1/g1FullGCMarker.hpp"

#include "gc/g1/g1StringDedup.hpp"

#include "gc/g1/g1StringDedupQueue.hpp"

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

#include "oops/access.inline.hpp"

#include "oops/compressedOops.inline.hpp"

#include "oops/oop.inline.hpp"

#include "utilities/debug.hpp"

inline bool G1FullGCMarker::mark_object(oop obj) {

  // Not marking closed archive objects.

  if (G1ArchiveAllocator::is_closed_archive_object(obj)) {

    return false;

  }

  // Try to mark.

  if (!_bitmap->par_mark(obj)) {

    // Lost mark race.

    return false;

  }

  // Marked by us, preserve if needed.

  markOop mark = obj->mark_raw();

  if (mark->must_be_preserved(obj) &&

      !G1ArchiveAllocator::is_open_archive_object(obj)) {

    preserved_stack()->push(obj, mark);

  }

  // Check if deduplicatable string.

  if (G1StringDedup::is_enabled()) {

    G1StringDedup::enqueue_from_mark(obj, _worker_id);

  }

  return true;

}

template <class T> inline void G1FullGCMarker::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);

    if (mark_object(obj)) {

      _oop_stack.push(obj);

      assert(_bitmap->is_marked(obj), "Must be marked now - map self");

    } else {

      assert(_bitmap->is_marked(obj) || G1ArchiveAllocator::is_closed_archive_object(obj),

             "Must be marked by other or closed archive object");

    }

  }

}

inline bool G1FullGCMarker::is_empty() {

  return _oop_stack.is_empty() && _objarray_stack.is_empty();

}

inline bool G1FullGCMarker::pop_object(oop& oop) {

  return _oop_stack.pop_overflow(oop) || _oop_stack.pop_local(oop);

}

inline void G1FullGCMarker::push_objarray(oop obj, size_t index) {

  ObjArrayTask task(obj, index);

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

  _objarray_stack.push(task);

}

inline bool G1FullGCMarker::pop_objarray(ObjArrayTask& arr) {

  return _objarray_stack.pop_overflow(arr) || _objarray_stack.pop_local(arr);

}

inline void G1FullGCMarker::follow_array(objArrayOop array) {

  follow_klass(array->klass());

  // Don't push empty arrays to avoid unnecessary work.

  if (array->length() > 0) {

    push_objarray(array, 0);

  }

}

void G1FullGCMarker::follow_array_chunk(objArrayOop array, int index) {

  const int len = array->length();

  const int beg_index = index;

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

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

  const int end_index = beg_index + stride;

  // Push the continuation first to allow more efficient work stealing.

  if (end_index < len) {

    push_objarray(array, end_index);

  }

  array->oop_iterate_range(mark_closure(), beg_index, end_index);

  if (VerifyDuringGC) {

    _verify_closure.set_containing_obj(array);

    NoHeaderExtendedOopClosure no(&_verify_closure);

    array->oop_iterate_range(&no, beg_index, end_index);

    if (_verify_closure.failures()) {

      assert(false, "Failed");

    }

  }

}

inline void G1FullGCMarker::follow_object(oop obj) {

  assert(_bitmap->is_marked(obj), "should be marked");

  if (obj->is_objArray()) {

    // Handle object arrays explicitly to allow them to

    // be split into chunks if needed.

    follow_array((objArrayOop)obj);

  } else {

    obj->oop_iterate(mark_closure());

    if (VerifyDuringGC) {

      if (obj->is_instance() && InstanceKlass::cast(obj->klass())->is_reference_instance_klass()) {

        return;

      }

      _verify_closure.set_containing_obj(obj);

      obj->oop_iterate_no_header(&_verify_closure);

      if (_verify_closure.failures()) {

        log_warning(gc, verify)("Failed after %d", _verify_closure._cc);

        assert(false, "Failed");

      }

    }

  }

}

void G1FullGCMarker::drain_stack() {

  do {

    oop obj;

    while (pop_object(obj)) {

      assert(_bitmap->is_marked(obj), "must be marked");

      follow_object(obj);

    }

    // Process ObjArrays one at a time to avoid marking stack bloat.

    ObjArrayTask task;

    if (pop_objarray(task)) {

      follow_array_chunk(objArrayOop(task.obj()), task.index());

    }

  } while (!is_empty());

}

inline void G1FullGCMarker::follow_klass(Klass* k) {

  oop op = k->klass_holder();

  mark_and_push(&op);

}

inline void G1FullGCMarker::follow_cld(ClassLoaderData* cld) {

  _cld_closure.do_cld(cld);

}

#endif