/*

 * Copyright (C) 2012 David Anderson

 *

 * This file is part of JITCraft.

 *

 * JITCraft is free software: you can redistribute it and/or modify it under

 * the terms of the GNU General Public License as published by the Free

 * Software Foundation, either version 3 of the License, or (at your option)

 * any later version.

 * 

 * Foobar 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 for more details.

 *

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

 * JITCraft. If not, see http://www.gnu.org/licenses/.

 */

#ifndef _include_jitcraft_heap_h_

#define _include_jitcraft_heap_h_

#include "Utility.h"

#include "Spaces.h"

#include "Barriers.h"

#include "Objects.h"

#include "Handles.h"

namespace jc {

class Zone;

// Heap-allocated objects go here. Heaps are thread-local.

class Heap

{

    Zone *zone_;

    HeapStack lifoSpace_;

    OldSpace mapSpace_;

    OldSpace oldSpace_;

    Map *metaMap_;

  public:

    enum Tenure {

        // Default, objects go into the nursery.

        Tenure_Default,

        // If objects are proven to not escape the stack, they can go into

        // a LIFO arena. Allocation on the LIFO arena is not guaranteed to

        // succeed; thus, objects may still be allocated in other arenas.

        Tenure_Stack,

        // Objects that should not go into the nursery (i.e. are expected

        // to be long-living) go here.

        Tenure_Old

    };

  private:

    Address newOldObject(size_t bytes);

    inline Address newStackObject(size_t bytes);

    inline Address newObject(size_t bytes, Tenure pretenure);

  public:

    Heap(Zone *zone);

    bool initialize();

    inline Object *allocate(Handle<Map> map, size_t byes, Tenure pretenure);

    Map *allocateMap(MapKind kind, size_t bytes);

    Map *metaMap() {

        return metaMap_;

    }

    inline Address lifoPosition() const {

        return lifoSpace_.position();

    }

    inline void unwindLifo(Address to) {

        lifoSpace_.unwind(to);

    }

};

}

#endif //_include_jitcraft_heap_h_