qtdeclarative/qv4managed.h

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#ifndef QMLJS_MANAGED_H
#define QMLJS_MANAGED_H

#include <QtCore/QString>
#include <QtCore/QVector>
#include <QtCore/QDebug>
#include <wtf/Platform.h>

namespace QQmlJS {

namespace VM {

class MemoryManager;
struct Object;
struct ObjectPrototype;
struct ExecutionContext;
struct ScriptFunction;

struct BooleanObject;
struct NumberObject;
struct StringObject;
struct ArrayObject;
struct DateObject;
struct FunctionObject;
struct RegExpObject;
struct ErrorObject;
struct ArgumentsObject;
struct ForeachIteratorObject;

struct Managed
{
private:
    void *operator new(size_t);
    Managed(const Managed &other);
    void operator = (const Managed &other);

protected:
    Managed() : markBit(0), inUse(1), extensible(true),
        isNonStrictArgumentsObject(false), isBuiltinFunction(false), type(Type_Object), unused(0) { }
    virtual ~Managed();

public:
    void *operator new(size_t size, MemoryManager *mm);
    void operator delete(void *ptr);

    inline void mark() {
        if (markBit)
            return;
        markBit = 1;
        markObjects();
    }

    enum Type {
        Type_Object = 0,
        Type_ArrayObject,
        Type_FunctionObject,
        Type_BooleanObject,
        Type_NumberObject,
        Type_StringObject,
        Type_DateObject,
        Type_RegExpObject,
        Type_ErrorObject,
        Type_ArgumentsObject,
        Type_ForeachIteratorObject
    };

    Object *asObject() { return reinterpret_cast<Object *>(this); }
    ArrayObject *asArrayObject() { return type == Type_ArrayObject ? reinterpret_cast<ArrayObject *>(this) : 0; }
    FunctionObject *asFunctionObject() { return type == Type_FunctionObject ? reinterpret_cast<FunctionObject *>(this) : 0; }
    BooleanObject *asBooleanObject() { return type == Type_BooleanObject ? reinterpret_cast<BooleanObject *>(this) : 0; }
    NumberObject *asNumberObject() { return type == Type_NumberObject ? reinterpret_cast<NumberObject *>(this) : 0; }
    StringObject *asStringObject() { return type == Type_StringObject ? reinterpret_cast<StringObject *>(this) : 0; }
    DateObject *asDateObject() { return type == Type_DateObject ? reinterpret_cast<DateObject *>(this) : 0; }
    RegExpObject *asRegExpObject() { return type == Type_RegExpObject ? reinterpret_cast<RegExpObject *>(this) : 0; }
    ErrorObject *asErrorObject() { return type == Type_ErrorObject ? reinterpret_cast<ErrorObject *>(this) : 0; }
    ArgumentsObject *asArgumentsObject() { return type == Type_ArgumentsObject ? reinterpret_cast<ArgumentsObject *>(this) : 0; }
    ForeachIteratorObject *asForeachIteratorObject() { return type == Type_ForeachIteratorObject ? reinterpret_cast<ForeachIteratorObject *>(this) : 0; }

    bool isArrayObject() const { return type == Type_ArrayObject; }
    bool isStringObject() const { return type == Type_StringObject; }

protected:
    virtual void markObjects() = 0;

    union {
        Managed *nextFree;
        struct {
            quintptr markBit :  1;
            quintptr inUse   :  1;
            quintptr extensible : 1; // used by Object
            quintptr isNonStrictArgumentsObject : 1;
            quintptr isBuiltinFunction : 1; // used by FunctionObject
            quintptr needsActivation : 1; // used by FunctionObject
            quintptr usesArgumentsObject : 1; // used by FunctionObject
            quintptr strictMode : 1; // used by FunctionObject
            quintptr type : 4;
#if CPU(X86_64)
            quintptr unused  : 51;
#elif CPU(X86)
            quintptr unused  : 19;
#else
#error "implement me"
#endif
        };
    };

private:
    friend class MemoryManager;
    friend struct Object;
    friend struct ObjectPrototype;
    friend class Array;
    friend struct ArrayPrototype;
    friend struct FunctionObject;
    friend struct ExecutionContext;
    friend struct ScriptFunction;
};

}
}

#endif