qtdeclarative/src/qml/jsruntime/qv4argumentsobject.cpp

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#include <qv4argumentsobject_p.h>
#include <qv4alloca_p.h>
#include <qv4scopedvalue_p.h>

using namespace QV4;

DEFINE_MANAGED_VTABLE(ArgumentsObject);

ArgumentsObject::ArgumentsObject(CallContext *context)
    : Object(context->strictMode ? context->engine->strictArgumentsObjectClass : context->engine->argumentsObjectClass)
    , context(context)
    , fullyCreated(false)
{
    type = Type_ArgumentsObject;
    flags &= ~SimpleArray;

    ExecutionEngine *v4 = context->engine;
    Scope scope(v4);
    ScopedObject protectThis(scope, this);

    if (context->strictMode) {
        Property pd = Property::fromAccessor(v4->thrower, v4->thrower);
        Q_ASSERT(CalleePropertyIndex == internalClass->find(context->engine->id_callee));
        Q_ASSERT(CallerPropertyIndex == internalClass->find(context->engine->id_caller));
        memberData[CalleePropertyIndex] = pd;
        memberData[CallerPropertyIndex] = pd;

        arrayReserve(context->callData->argc);
        for (int i = 0; i < context->callData->argc; ++i)
            arrayData[i].value = context->callData->args[i];
        arrayDataLen = context->callData->argc;
        fullyCreated = true;
    } else {
        Q_ASSERT(CalleePropertyIndex == internalClass->find(context->engine->id_callee));
        memberData[CalleePropertyIndex].value = context->function->asReturnedValue();
        isNonStrictArgumentsObject = true;
    }
    Q_ASSERT(LengthPropertyIndex == internalClass->find(context->engine->id_length));
    Property *lp = memberData + ArrayObject::LengthPropertyIndex;
    lp->value = Primitive::fromInt32(context->realArgumentCount);

    setVTable(&static_vtbl);
}

void ArgumentsObject::destroy(Managed *that)
{
    static_cast<ArgumentsObject *>(that)->~ArgumentsObject();
}

void ArgumentsObject::fullyCreate()
{
    if (fullyCreated)
        return;

    uint numAccessors = qMin((int)context->function->formalParameterCount, context->realArgumentCount);
    uint argCount = qMin(context->realArgumentCount, context->callData->argc);
    arrayReserve(argCount);
    ensureArrayAttributes();
    context->engine->requireArgumentsAccessors(numAccessors);
    for (uint i = 0; i < (uint)numAccessors; ++i) {
        mappedArguments.append(context->callData->args[i]);
        arrayData[i] = context->engine->argumentsAccessors.at(i);
        arrayAttributes[i] = Attr_Accessor;
    }
    for (uint i = numAccessors; i < argCount; ++i) {
        arrayData[i] = Property::fromValue(context->callData->args[i]);
        arrayAttributes[i] = Attr_Data;
    }
    arrayDataLen = argCount;

    fullyCreated = true;
}

bool ArgumentsObject::defineOwnProperty(ExecutionContext *ctx, uint index, const Property &desc, PropertyAttributes attrs)
{
    fullyCreate();

    Scope scope(ctx);
    uint pidx = propertyIndexFromArrayIndex(index);
    Property *pd = arrayData + pidx;
    Property map;
    PropertyAttributes mapAttrs;
    bool isMapped = false;
    if (pd && index < (uint)mappedArguments.size())
        isMapped = arrayAttributes && arrayAttributes[pidx].isAccessor() && pd->getter() == context->engine->argumentsAccessors.at(index).getter();

    if (isMapped) {
        map = *pd;
        mapAttrs = arrayAttributes[pidx];
        arrayAttributes[pidx] = Attr_Data;
        pd->value = mappedArguments.at(index);
    }

    isNonStrictArgumentsObject = false;
    bool strict = ctx->strictMode;
    ctx->strictMode = false;
    bool result = Object::__defineOwnProperty__(ctx, index, desc, attrs);
    ctx->strictMode = strict;
    isNonStrictArgumentsObject = true;

    if (isMapped && attrs.isData()) {
        ScopedCallData callData(scope, 1);
        callData->thisObject = this->asReturnedValue();
        callData->args[0] = desc.value;
        map.setter()->call(callData);

        if (attrs.isWritable()) {
            *pd = map;
            arrayAttributes[pidx] = mapAttrs;
        }
    }

    if (ctx->strictMode && !result)
        return ctx->throwTypeError();
    return result;
}

ReturnedValue ArgumentsObject::getIndexed(Managed *m, uint index, bool *hasProperty)
{
    ArgumentsObject *args = static_cast<ArgumentsObject *>(m);
    if (args->fullyCreated)
        return Object::getIndexed(m, index, hasProperty);

    if (index < static_cast<uint>(args->context->callData->argc)) {
        if (hasProperty)
            *hasProperty = true;
        return args->context->callData->args[index].asReturnedValue();
    }
    return Encode::undefined();
}

void ArgumentsObject::putIndexed(Managed *m, uint index, const ValueRef value)
{
    ArgumentsObject *args = static_cast<ArgumentsObject *>(m);
    if (!args->fullyCreated && index >= static_cast<uint>(args->context->callData->argc))
        args->fullyCreate();

    if (args->fullyCreated) {
        Object::putIndexed(m, index, value);
        return;
    }

    args->context->callData->args[index] = value;
}

bool ArgumentsObject::deleteIndexedProperty(Managed *m, uint index)
{
    ArgumentsObject *args = static_cast<ArgumentsObject *>(m);
    if (!args->fullyCreated)
        args->fullyCreate();
    return Object::deleteIndexedProperty(m, index);
}

PropertyAttributes ArgumentsObject::queryIndexed(const Managed *m, uint index)
{
    const ArgumentsObject *args = static_cast<const ArgumentsObject *>(m);
    if (args->fullyCreated)
        return Object::queryIndexed(m, index);

    uint numAccessors = qMin((int)args->context->function->formalParameterCount, args->context->realArgumentCount);
    uint argCount = qMin(args->context->realArgumentCount, args->context->callData->argc);
    if (index >= argCount)
        return PropertyAttributes();
    if (index >= numAccessors)
        return Attr_Data;
    return Attr_Accessor;
}

DEFINE_MANAGED_VTABLE(ArgumentsGetterFunction);

ReturnedValue ArgumentsGetterFunction::call(Managed *getter, CallData *callData)
{
    ExecutionEngine *v4 = getter->engine();
    Scope scope(v4);
    Scoped<ArgumentsGetterFunction> g(scope, static_cast<ArgumentsGetterFunction *>(getter));
    Scoped<ArgumentsObject> o(scope, callData->thisObject.as<ArgumentsObject>());
    if (!o)
        return v4->current->throwTypeError();

    Q_ASSERT(g->index < static_cast<unsigned>(o->context->callData->argc));
    return o->context->argument(g->index);
}

DEFINE_MANAGED_VTABLE(ArgumentsSetterFunction);

ReturnedValue ArgumentsSetterFunction::call(Managed *setter, CallData *callData)
{
    ExecutionEngine *v4 = setter->engine();
    Scope scope(v4);
    Scoped<ArgumentsSetterFunction> s(scope, static_cast<ArgumentsSetterFunction *>(setter));
    Scoped<ArgumentsObject> o(scope, callData->thisObject.as<ArgumentsObject>());
    if (!o)
        return v4->current->throwTypeError();

    Q_ASSERT(s->index < static_cast<unsigned>(o->context->callData->argc));
    o->context->callData->args[s->index] = callData->argc ? callData->args[0].asReturnedValue() : Encode::undefined();
    return Encode::undefined();
}

void ArgumentsObject::markObjects(Managed *that, ExecutionEngine *e)
{
    ArgumentsObject *o = static_cast<ArgumentsObject *>(that);
    o->context->mark(e);
    for (int i = 0; i < o->mappedArguments.size(); ++i)
        o->mappedArguments.at(i).mark(e);

    Object::markObjects(that, e);
}