/*

 * Copyright (C) 2009 Apple Inc. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY

 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 

 */

#ifndef ParserArena_h

#define ParserArena_h

#include "Identifier.h"

#include <wtf/SegmentedVector.h>

namespace JSC {

    class ParserArenaDeletable;

    class ParserArenaRefCounted;

    class IdentifierArena : public FastAllocBase {

    public:

        ALWAYS_INLINE const Identifier& makeIdentifier(JSGlobalData*, const UChar* characters, size_t length);

        const Identifier& makeNumericIdentifier(JSGlobalData*, double number);

        void clear() { m_identifiers.clear(); }

        bool isEmpty() const { return m_identifiers.isEmpty(); }

    private:

        typedef SegmentedVector<Identifier, 64> IdentifierVector;

        IdentifierVector m_identifiers;

    };

    ALWAYS_INLINE const Identifier& IdentifierArena::makeIdentifier(JSGlobalData* globalData, const UChar* characters, size_t length)

    {

        m_identifiers.append(Identifier(globalData, characters, length));

        return m_identifiers.last();

    }

    inline const Identifier& IdentifierArena::makeNumericIdentifier(JSGlobalData* globalData, double number)

    {

        m_identifiers.append(Identifier(globalData, UString::from(number)));

        return m_identifiers.last();

    }

    class ParserArena : Noncopyable {

    public:

        ParserArena();

        ~ParserArena();

        void swap(ParserArena& otherArena)

        {

            std::swap(m_freeableMemory, otherArena.m_freeableMemory);

            std::swap(m_freeablePoolEnd, otherArena.m_freeablePoolEnd);

            m_identifierArena.swap(otherArena.m_identifierArena);

            m_freeablePools.swap(otherArena.m_freeablePools);

            m_deletableObjects.swap(otherArena.m_deletableObjects);

            m_refCountedObjects.swap(otherArena.m_refCountedObjects);

        }

        void* allocateFreeable(size_t size)

        {

            ASSERT(size);

            ASSERT(size <= freeablePoolSize);

            size_t alignedSize = alignSize(size);

            ASSERT(alignedSize <= freeablePoolSize);

            if (UNLIKELY(static_cast<size_t>(m_freeablePoolEnd - m_freeableMemory) < alignedSize))

                allocateFreeablePool();

            void* block = m_freeableMemory;

            m_freeableMemory += alignedSize;

            return block;

        }

        void* allocateDeletable(size_t size)

        {

            ParserArenaDeletable* deletable = static_cast<ParserArenaDeletable*>(fastMalloc(size));

            m_deletableObjects.append(deletable);

            return deletable;

        }

        void derefWithArena(PassRefPtr<ParserArenaRefCounted>);

        bool contains(ParserArenaRefCounted*) const;

        ParserArenaRefCounted* last() const;

        void removeLast();

        bool isEmpty() const;

        void reset();

        IdentifierArena& identifierArena() { return *m_identifierArena; }

    private:

        static const size_t freeablePoolSize = 8000;

        static size_t alignSize(size_t size)

        {

            return (size + sizeof(WTF::AllocAlignmentInteger) - 1) & ~(sizeof(WTF::AllocAlignmentInteger) - 1);

        }

        void* freeablePool();

        void allocateFreeablePool();

        void deallocateObjects();

        char* m_freeableMemory;

        char* m_freeablePoolEnd;

        OwnPtr<IdentifierArena> m_identifierArena;

        Vector<void*> m_freeablePools;

        Vector<ParserArenaDeletable*> m_deletableObjects;

        Vector<RefPtr<ParserArenaRefCounted> > m_refCountedObjects;

    };

}

#endif