Fix CallContext to not hold arguments on the C stack anymore

Change-Id: I35f46cce4f243d4b8b2bac9244f8fc26836f413b
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

22 files changed, 381 insertions, 376 deletions

diff --git a/src/qml/jsruntime/qv4argumentsobject.cpp b/src/qml/jsruntime/qv4argumentsobject.cpp
index be4fbe60b8..34ccd0af49 100644
--- a/src/qml/jsruntime/qv4argumentsobject.cpp
+++ b/src/qml/jsruntime/qv4argumentsobject.cpp
@@ -64,28 +64,28 @@ ArgumentsObject::ArgumentsObject(CallContext *context)
         memberData[CalleePropertyIndex] = pd;
         memberData[CallerPropertyIndex] = pd;
 
-        arrayReserve(context->argumentCount);
-        for (unsigned int i = 0; i < context->argumentCount; ++i)
-            arrayData[i].value = context->arguments[i];
-        arrayDataLen = context->argumentCount;
+        arrayReserve(context->callData->argc);
+        for (unsigned int i = 0; i < context->callData->argc; ++i)
+            arrayData[i].value = context->callData->args[i];
+        arrayDataLen = context->callData->argc;
     } else {
         internalClass = engine()->argumentsObjectClass;
         Q_ASSERT(CalleePropertyIndex == internalClass->find(context->engine->id_callee));
         memberData[CalleePropertyIndex].value = Value::fromObject(context->function);
         isNonStrictArgumentsObject = true;
 
-        uint numAccessors = qMin(context->function->formalParameterCount, context->realArgumentCount);
-        uint argCount = qMin((uint)context->realArgumentCount, context->argumentCount);
+        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->arguments[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->arguments[i]);
+            arrayData[i] = Property::fromValue(context->callData->args[i]);
             arrayAttributes[i] = Attr_Data;
         }
         arrayDataLen = argCount;
@@ -155,7 +155,7 @@ ReturnedValue ArgumentsGetterFunction::call(Managed *getter, CallData *callData)
     if (!o)
         getter->engine()->current->throwTypeError();
 
-    assert(g->index < o->context->argumentCount);
+    assert(g->index < o->context->callData->argc);
     return o->context->argument(g->index);
 }
 
@@ -171,8 +171,8 @@ ReturnedValue ArgumentsSetterFunction::call(Managed *setter, CallData *callData)
     if (!o)
         setter->engine()->current->throwTypeError();
 
-    assert(s->index < o->context->argumentCount);
-    o->context->arguments[s->index] = callData->argc ? callData->args[0] : Value::undefinedValue();
+    assert(s->index < o->context->callData->argc);
+    o->context->callData->args[s->index] = callData->argc ? callData->args[0] : Value::undefinedValue();
     return Value::undefinedValue().asReturnedValue();
 }
 
diff --git a/src/qml/jsruntime/qv4arrayobject.cpp b/src/qml/jsruntime/qv4arrayobject.cpp
index 44687463e2..2c5670ef92 100644
--- a/src/qml/jsruntime/qv4arrayobject.cpp
+++ b/src/qml/jsruntime/qv4arrayobject.cpp
@@ -131,19 +131,19 @@ uint ArrayPrototype::getLength(ExecutionContext *ctx, Object *o)
 
 ReturnedValue ArrayPrototype::method_isArray(SimpleCallContext *ctx)
 {
-    bool isArray = ctx->argumentCount ? ctx->arguments[0].asArrayObject() : false;
+    bool isArray = ctx->callData->argc ? ctx->callData->args[0].asArrayObject() : false;
     return Encode(isArray);
 }
 
 ReturnedValue ArrayPrototype::method_toString(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedObject o(scope, ctx->thisObject, ScopedObject::Convert);
+    ScopedObject o(scope, ctx->callData->thisObject, ScopedObject::Convert);
     ScopedString s(scope, ctx->engine->newString("join"));
     ScopedFunctionObject f(scope, o->get(s));
     if (!!f) {
         ScopedCallData d(scope, 0);
-        d->thisObject = ctx->thisObject;
+        d->thisObject = ctx->callData->thisObject;
         return f->call(d);
     }
     return ObjectPrototype::method_toString(ctx);
@@ -159,7 +159,7 @@ ReturnedValue ArrayPrototype::method_concat(SimpleCallContext *ctx)
     Scope scope(ctx);
     Scoped<ArrayObject> result(scope, ctx->engine->newArrayObject());
 
-    ScopedObject thisObject(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject thisObject(scope, ctx->callData->thisObject.toObject(ctx));
     ScopedArrayObject instance(scope, thisObject);
     if (instance) {
         result->copyArrayData(instance.getPointer());
@@ -168,12 +168,12 @@ ReturnedValue ArrayPrototype::method_concat(SimpleCallContext *ctx)
     }
 
     ScopedArrayObject elt(scope);
-    for (uint i = 0; i < ctx->argumentCount; ++i) {
-        elt = ctx->arguments[i];
+    for (uint i = 0; i < ctx->callData->argc; ++i) {
+        elt = ctx->callData->args[i];
         if (elt)
             result->arrayConcat(elt.getPointer());
         else
-            result->arraySet(getLength(ctx, result.getPointer()), ctx->arguments[i]);
+            result->arraySet(getLength(ctx, result.getPointer()), ctx->callData->args[i]);
     }
 
     return result.asReturnedValue();
@@ -190,7 +190,7 @@ ReturnedValue ArrayPrototype::method_join(SimpleCallContext *ctx)
     else
         r4 = arg->toQString();
 
-    ScopedObject self(scope, ctx->thisObject);
+    ScopedObject self(scope, ctx->callData->thisObject);
     ScopedValue length(scope, self->get(ctx->engine->id_length));
     const quint32 r2 = length->isUndefined() ? 0 : length->toUInt32();
 
@@ -237,7 +237,7 @@ ReturnedValue ArrayPrototype::method_join(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_pop(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedObject instance(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject instance(scope, ctx->callData->thisObject.toObject(ctx));
     uint len = getLength(ctx, instance.getPointer());
 
     if (!len) {
@@ -259,18 +259,18 @@ ReturnedValue ArrayPrototype::method_pop(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_push(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedObject instance(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject instance(scope, ctx->callData->thisObject.toObject(ctx));
     uint len = getLength(ctx, instance.getPointer());
 
-    if (len + ctx->argumentCount < len) {
+    if (len + ctx->callData->argc < len) {
         // ughh...
         double l = len;
         ScopedString s(scope);
-        for (int i = 0; i < ctx->argumentCount; ++i) {
+        for (int i = 0; i < ctx->callData->argc; ++i) {
             s = Value::fromDouble(l + i).toString(ctx);
-            instance->put(s, ctx->arguments[i]);
+            instance->put(s, ctx->callData->args[i]);
         }
-        double newLen = l + ctx->argumentCount;
+        double newLen = l + ctx->callData->argc;
         if (!instance->isArrayObject())
             instance->put(ctx->engine->id_length, ScopedValue(scope, Value::fromDouble(newLen)));
         else
@@ -279,24 +279,24 @@ ReturnedValue ArrayPrototype::method_push(SimpleCallContext *ctx)
     }
 
     if (!instance->protoHasArray() && instance->arrayDataLen <= len) {
-        for (uint i = 0; i < ctx->argumentCount; ++i) {
+        for (uint i = 0; i < ctx->callData->argc; ++i) {
             if (!instance->sparseArray) {
                 if (len >= instance->arrayAlloc)
                     instance->arrayReserve(len + 1);
-                instance->arrayData[len].value = ctx->arguments[i];
+                instance->arrayData[len].value = ctx->callData->args[i];
                 if (instance->arrayAttributes)
                     instance->arrayAttributes[len] = Attr_Data;
                 instance->arrayDataLen = len + 1;
             } else {
-                uint i = instance->allocArrayValue(ctx->arguments[i]);
+                uint i = instance->allocArrayValue(ctx->callData->args[i]);
                 instance->sparseArray->push_back(i, len);
             }
             ++len;
         }
     } else {
-        for (uint i = 0; i < ctx->argumentCount; ++i)
-            instance->putIndexed(len + i, ctx->arguments[i]);
-        len += ctx->argumentCount;
+        for (uint i = 0; i < ctx->callData->argc; ++i)
+            instance->putIndexed(len + i, ctx->callData->args[i]);
+        len += ctx->callData->argc;
     }
     if (instance->isArrayObject())
         instance->setArrayLengthUnchecked(len);
@@ -309,7 +309,7 @@ ReturnedValue ArrayPrototype::method_push(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_reverse(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedObject instance(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject instance(scope, ctx->callData->thisObject.toObject(ctx));
     uint length = getLength(ctx, instance.getPointer());
 
     int lo = 0, hi = length - 1;
@@ -335,7 +335,7 @@ ReturnedValue ArrayPrototype::method_reverse(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_shift(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedObject instance(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject instance(scope, ctx->callData->thisObject.toObject(ctx));
     uint len = getLength(ctx, instance.getPointer());
 
     if (!len) {
@@ -389,7 +389,7 @@ ReturnedValue ArrayPrototype::method_shift(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_slice(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedObject o(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject o(scope, ctx->callData->thisObject.toObject(ctx));
 
     Scoped<ArrayObject> result(scope, ctx->engine->newArrayObject());
     uint len = getLength(ctx, o.getPointer());
@@ -402,8 +402,8 @@ ReturnedValue ArrayPrototype::method_slice(SimpleCallContext *ctx)
     else
         start = (uint) s;
     uint end = len;
-    if (ctx->argumentCount > 1 && !ctx->arguments[1].isUndefined()) {
-        double e = ctx->arguments[1].toInteger();
+    if (ctx->callData->argc > 1 && !ctx->callData->args[1].isUndefined()) {
+        double e = ctx->callData->args[1].toInteger();
         if (e < 0)
             end = (uint)qMax(len + e, 0.);
         else if (e > len)
@@ -428,19 +428,19 @@ ReturnedValue ArrayPrototype::method_slice(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_sort(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<Object> instance(scope, ctx->thisObject.toObject(ctx));
+    Scoped<Object> instance(scope, ctx->callData->thisObject.toObject(ctx));
 
     uint len = getLength(ctx, instance.getPointer());
 
     ScopedValue comparefn(scope, ctx->argument(0));
     instance->arraySort(ctx, instance, comparefn, len);
-    return ctx->thisObject.asReturnedValue();
+    return ctx->callData->thisObject.asReturnedValue();
 }
 
 ReturnedValue ArrayPrototype::method_splice(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedObject instance(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject instance(scope, ctx->callData->thisObject.toObject(ctx));
     uint len = getLength(ctx, instance.getPointer());
 
     Scoped<ArrayObject> newArray(scope, ctx->engine->newArrayObject());
@@ -461,7 +461,7 @@ ReturnedValue ArrayPrototype::method_splice(SimpleCallContext *ctx)
     }
     newArray->setArrayLengthUnchecked(deleteCount);
 
-    uint itemCount = ctx->argumentCount < 2 ? 0 : ctx->argumentCount - 2;
+    uint itemCount = ctx->callData->argc < 2 ? 0 : ctx->callData->argc - 2;
 
     ScopedValue v(scope);
     if (itemCount < deleteCount) {
@@ -489,7 +489,7 @@ ReturnedValue ArrayPrototype::method_splice(SimpleCallContext *ctx)
     }
 
     for (uint i = 0; i < itemCount; ++i)
-        instance->putIndexed(start + i, ctx->arguments[i + 2]);
+        instance->putIndexed(start + i, ctx->callData->args[i + 2]);
 
     ctx->strictMode = true;
     instance->put(ctx->engine->id_length, ScopedValue(scope, Value::fromDouble(len - deleteCount + itemCount)));
@@ -500,12 +500,12 @@ ReturnedValue ArrayPrototype::method_splice(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_unshift(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedObject instance(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject instance(scope, ctx->callData->thisObject.toObject(ctx));
     uint len = getLength(ctx, instance.getPointer());
 
     ScopedValue v(scope);
     if (!instance->protoHasArray() && instance->arrayDataLen <= len) {
-        for (int i = ctx->argumentCount - 1; i >= 0; --i) {
+        for (int i = ctx->callData->argc - 1; i >= 0; --i) {
             v = ctx->argument(i);
 
             if (!instance->sparseArray) {
@@ -530,15 +530,15 @@ ReturnedValue ArrayPrototype::method_unshift(SimpleCallContext *ctx)
             bool exists;
             v = instance->getIndexed(k - 1, &exists);
             if (exists)
-                instance->putIndexed(k + ctx->argumentCount - 1, v);
+                instance->putIndexed(k + ctx->callData->argc - 1, v);
             else
-                instance->deleteIndexedProperty(k + ctx->argumentCount - 1);
+                instance->deleteIndexedProperty(k + ctx->callData->argc - 1);
         }
-        for (uint i = 0; i < ctx->argumentCount; ++i)
-            instance->putIndexed(i, ctx->arguments[i]);
+        for (uint i = 0; i < ctx->callData->argc; ++i)
+            instance->putIndexed(i, ctx->callData->args[i]);
     }
 
-    uint newLen = len + ctx->argumentCount;
+    uint newLen = len + ctx->callData->argc;
     if (instance->isArrayObject())
         instance->setArrayLengthUnchecked(newLen);
     else
@@ -551,7 +551,7 @@ ReturnedValue ArrayPrototype::method_indexOf(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
 
-    ScopedObject instance(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject instance(scope, ctx->callData->thisObject.toObject(ctx));
     uint len = getLength(ctx, instance.getPointer());
     if (!len)
         return Value::fromInt32(-1).asReturnedValue();
@@ -559,13 +559,13 @@ ReturnedValue ArrayPrototype::method_indexOf(SimpleCallContext *ctx)
     ScopedValue searchValue(scope);
     uint fromIndex = 0;
 
-    if (ctx->argumentCount >= 1)
-        searchValue = ctx->arguments[0];
+    if (ctx->callData->argc >= 1)
+        searchValue = ctx->callData->args[0];
     else
         searchValue = Value::undefinedValue();
 
-    if (ctx->argumentCount >= 2) {
-        double f = ctx->arguments[1].toInteger();
+    if (ctx->callData->argc >= 2) {
+        double f = ctx->callData->args[1].toInteger();
         if (f >= len)
             return Encode(-1);
         if (f < 0)
@@ -591,7 +591,7 @@ ReturnedValue ArrayPrototype::method_lastIndexOf(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
 
-    ScopedObject instance(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject instance(scope, ctx->callData->thisObject.toObject(ctx));
     uint len = getLength(ctx, instance.getPointer());
     if (!len)
         return Value::fromInt32(-1).asReturnedValue();
@@ -599,13 +599,13 @@ ReturnedValue ArrayPrototype::method_lastIndexOf(SimpleCallContext *ctx)
     ScopedValue searchValue(scope);
     uint fromIndex = len;
 
-    if (ctx->argumentCount >= 1)
+    if (ctx->callData->argc >= 1)
         searchValue = ctx->argument(0);
     else
         searchValue = Value::undefinedValue();
 
-    if (ctx->argumentCount >= 2) {
-        double f = ctx->arguments[1].toInteger();
+    if (ctx->callData->argc >= 2) {
+        double f = ctx->callData->args[1].toInteger();
         if (f > 0)
             f = qMin(f, (double)(len - 1));
         else if (f < 0) {
@@ -630,7 +630,7 @@ ReturnedValue ArrayPrototype::method_lastIndexOf(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_every(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<Object> instance(scope, ctx->thisObject.toObject(ctx));
+    Scoped<Object> instance(scope, ctx->callData->thisObject.toObject(ctx));
 
     uint len = getLength(ctx, instance.getPointer());
 
@@ -662,7 +662,7 @@ ReturnedValue ArrayPrototype::method_every(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_some(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<Object> instance(scope, ctx->thisObject.toObject(ctx));
+    Scoped<Object> instance(scope, ctx->callData->thisObject.toObject(ctx));
 
     uint len = getLength(ctx, instance.getPointer());
 
@@ -693,7 +693,7 @@ ReturnedValue ArrayPrototype::method_some(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_forEach(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<Object> instance(scope, ctx->thisObject.toObject(ctx));
+    Scoped<Object> instance(scope, ctx->callData->thisObject.toObject(ctx));
 
     uint len = getLength(ctx, instance.getPointer());
 
@@ -722,7 +722,7 @@ ReturnedValue ArrayPrototype::method_forEach(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_map(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<Object> instance(scope, ctx->thisObject.toObject(ctx));
+    Scoped<Object> instance(scope, ctx->callData->thisObject.toObject(ctx));
 
     uint len = getLength(ctx, instance.getPointer());
 
@@ -757,7 +757,7 @@ ReturnedValue ArrayPrototype::method_map(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_filter(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<Object> instance(scope, ctx->thisObject.toObject(ctx));
+    Scoped<Object> instance(scope, ctx->callData->thisObject.toObject(ctx));
 
     uint len = getLength(ctx, instance.getPointer());
 
@@ -796,7 +796,7 @@ ReturnedValue ArrayPrototype::method_filter(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_reduce(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<Object> instance(scope, ctx->thisObject.toObject(ctx));
+    Scoped<Object> instance(scope, ctx->callData->thisObject.toObject(ctx));
 
     uint len = getLength(ctx, instance.getPointer());
 
@@ -808,7 +808,7 @@ ReturnedValue ArrayPrototype::method_reduce(SimpleCallContext *ctx)
     ScopedValue acc(scope);
     ScopedValue v(scope);
 
-    if (ctx->argumentCount > 1) {
+    if (ctx->callData->argc > 1) {
         acc = ctx->argument(1);
     } else {
         bool kPresent = false;
@@ -844,7 +844,7 @@ ReturnedValue ArrayPrototype::method_reduce(SimpleCallContext *ctx)
 ReturnedValue ArrayPrototype::method_reduceRight(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<Object> instance(scope, ctx->thisObject.toObject(ctx));
+    Scoped<Object> instance(scope, ctx->callData->thisObject.toObject(ctx));
 
     uint len = getLength(ctx, instance.getPointer());
 
@@ -853,7 +853,7 @@ ReturnedValue ArrayPrototype::method_reduceRight(SimpleCallContext *ctx)
         ctx->throwTypeError();
 
     if (len == 0) {
-        if (ctx->argumentCount == 1)
+        if (ctx->callData->argc == 1)
             ctx->throwTypeError();
         return ctx->argument(1);
     }
@@ -861,7 +861,7 @@ ReturnedValue ArrayPrototype::method_reduceRight(SimpleCallContext *ctx)
     uint k = len;
     ScopedValue acc(scope);
     ScopedValue v(scope);
-    if (ctx->argumentCount > 1) {
+    if (ctx->callData->argc > 1) {
         acc = ctx->argument(1);
     } else {
         bool kPresent = false;
diff --git a/src/qml/jsruntime/qv4booleanobject.cpp b/src/qml/jsruntime/qv4booleanobject.cpp
index be801a67c2..7e0831232c 100644
--- a/src/qml/jsruntime/qv4booleanobject.cpp
+++ b/src/qml/jsruntime/qv4booleanobject.cpp
@@ -77,10 +77,10 @@ void BooleanPrototype::init(ExecutionEngine *engine, const Value &ctor)
 ReturnedValue BooleanPrototype::method_toString(SimpleCallContext *ctx)
 {
     bool result;
-    if (ctx->thisObject.isBoolean()) {
-        result = ctx->thisObject.booleanValue();
+    if (ctx->callData->thisObject.isBoolean()) {
+        result = ctx->callData->thisObject.booleanValue();
     } else {
-        BooleanObject *thisObject = ctx->thisObject.asBooleanObject();
+        BooleanObject *thisObject = ctx->callData->thisObject.asBooleanObject();
         if (!thisObject)
             ctx->throwTypeError();
         result = thisObject->value.booleanValue();
@@ -91,7 +91,7 @@ ReturnedValue BooleanPrototype::method_toString(SimpleCallContext *ctx)
 
 ReturnedValue BooleanPrototype::method_valueOf(SimpleCallContext *ctx)
 {
-    BooleanObject *thisObject = ctx->thisObject.asBooleanObject();
+    BooleanObject *thisObject = ctx->callData->thisObject.asBooleanObject();
     if (!thisObject)
         ctx->throwTypeError();
 
diff --git a/src/qml/jsruntime/qv4context.cpp b/src/qml/jsruntime/qv4context.cpp
index 8d07c5220a..ae9a72d760 100644
--- a/src/qml/jsruntime/qv4context.cpp
+++ b/src/qml/jsruntime/qv4context.cpp
@@ -51,7 +51,7 @@
 
 using namespace QV4;
 
-CallContext *ExecutionContext::newCallContext(void *stackSpace, FunctionObject *function, CallData *callData)
+CallContext *ExecutionContext::newCallContext(void *stackSpace, Value *locals, FunctionObject *function, CallData *callData)
 {
     CallContext *c = (CallContext *)stackSpace;
 #ifndef QT_NO_DEBUG
@@ -63,11 +63,8 @@ CallContext *ExecutionContext::newCallContext(void *stackSpace, FunctionObject *
     c->initBaseContext(Type_CallContext, engine, this);
 
     c->function = function;
-    // ###
-    c->arguments = const_cast<SafeValue *>(callData->args);
+    c->callData = callData;
     c->realArgumentCount = callData->argc;
-    c->argumentCount = callData->argc;
-    c->thisObject = callData->thisObject;
 
     c->strictMode = function->strictMode;
     c->marked = false;
@@ -85,7 +82,7 @@ CallContext *ExecutionContext::newCallContext(void *stackSpace, FunctionObject *
         c->runtimeStrings = c->compilationUnit->runtimeStrings;
     }
 
-    c->locals = (Value *)(c + 1);
+    c->locals = locals;
 
     if (function->varCount)
         std::fill(c->locals, c->locals + function->varCount, Value::undefinedValue());
@@ -94,8 +91,8 @@ CallContext *ExecutionContext::newCallContext(void *stackSpace, FunctionObject *
 #ifndef QT_NO_DEBUG
         Q_ASSERT(function->formalParameterCount <= QV4::Global::ReservedArgumentCount);
 #endif
-        std::fill(c->arguments + callData->argc, c->arguments + function->formalParameterCount, Value::undefinedValue());
-        c->argumentCount = function->formalParameterCount;
+        std::fill(c->callData->args + callData->argc, c->callData->args + function->formalParameterCount, Value::undefinedValue());
+        c->callData->argc = function->formalParameterCount;
     }
 
     return c;
@@ -111,7 +108,6 @@ CallContext *ExecutionContext::newCallContext(FunctionObject *function, CallData
 
     c->function = function;
     c->realArgumentCount = callData->argc;
-    c->thisObject = callData->thisObject;
 
     c->strictMode = function->strictMode;
     c->marked = false;
@@ -134,12 +130,11 @@ CallContext *ExecutionContext::newCallContext(FunctionObject *function, CallData
     if (function->varCount)
         std::fill(c->locals, c->locals + function->varCount, Value::undefinedValue());
 
-    c->argumentCount = qMax((uint)callData->argc, function->formalParameterCount);
-    c->arguments = static_cast<SafeValue *>(c->locals + function->varCount);
-    if (callData->argc)
-        ::memcpy(c->arguments, callData->args, callData->argc * sizeof(Value));
+    c->callData = reinterpret_cast<CallData *>(c->locals + function->varCount);
+    ::memcpy(c->callData, callData, sizeof(CallData) + (callData->argc - 1) * sizeof(Value));
     if (callData->argc < function->formalParameterCount)
-        std::fill(c->arguments + callData->argc, c->arguments + function->formalParameterCount, Value::undefinedValue());
+        std::fill(c->callData->args + c->callData->argc, c->callData->args + function->formalParameterCount, Value::undefinedValue());
+    c->callData->argc = qMax((uint)callData->argc, function->formalParameterCount);
 
     return c;
 }
@@ -222,14 +217,17 @@ unsigned int ExecutionContext::variableCount() const
 void GlobalContext::initGlobalContext(ExecutionEngine *eng)
 {
     initBaseContext(Type_GlobalContext, eng, /*parentContext*/0);
-    thisObject = Value::fromObject(eng->globalObject);
+    callData = reinterpret_cast<CallData *>(this + 1);
+    callData->tag = QV4::Value::Integer_Type;
+    callData->argc = 0;
+    callData->thisObject = Value::fromObject(eng->globalObject);
     global = 0;
 }
 
 void WithContext::initWithContext(ExecutionContext *p, Object *with)
 {
     initBaseContext(Type_WithContext, p->engine, p);
-    thisObject = p->thisObject;
+    callData = p->callData;
     outer = p;
     lookups = p->lookups;
     runtimeStrings = p->runtimeStrings;
@@ -243,7 +241,7 @@ void CatchContext::initCatchContext(ExecutionContext *p, String *exceptionVarNam
 {
     initBaseContext(Type_CatchContext, p->engine, p);
     strictMode = p->strictMode;
-    thisObject = p->thisObject;
+    callData = p->callData;
     outer = p;
     lookups = p->lookups;
     runtimeStrings = p->runtimeStrings;
@@ -259,9 +257,10 @@ void CallContext::initQmlContext(ExecutionContext *parentContext, Object *qml, F
     initBaseContext(Type_QmlContext, parentContext->engine, parentContext);
 
     this->function = function;
-    this->arguments = 0;
-    this->argumentCount = 0;
-    this->thisObject = Value::undefinedValue();
+    this->callData = reinterpret_cast<CallData *>(this + 1);
+    this->callData->tag = QV4::Value::Integer_Type;
+    this->callData->argc = 0;
+    this->callData->thisObject = Value::undefinedValue();
 
     strictMode = true;
     marked = false;
@@ -326,7 +325,7 @@ bool ExecutionContext::deleteProperty(const StringRef name)
 
 bool CallContext::needsOwnArguments() const
 {
-    return function->needsActivation || argumentCount < function->formalParameterCount;
+    return function->needsActivation || callData->argc < function->formalParameterCount;
 }
 
 void ExecutionContext::mark()
@@ -338,19 +337,17 @@ void ExecutionContext::mark()
     if (type != Type_SimpleCallContext && outer)
         outer->mark();
 
-    thisObject.mark();
+    callData->thisObject.mark();
+    for (unsigned arg = 0; arg < callData->argc; ++arg)
+        callData->args[arg].mark();
 
-    if (type >= Type_SimpleCallContext) {
+    if (type >= Type_CallContext) {
         QV4::CallContext *c = static_cast<CallContext *>(this);
-        for (unsigned arg = 0, lastArg = c->argumentCount; arg < lastArg; ++arg)
-            c->arguments[arg].mark();
-        if (type >= Type_CallContext) {
-            for (unsigned local = 0, lastLocal = c->variableCount(); local < lastLocal; ++local)
-                c->locals[local].mark();
-            if (c->activation)
-                c->activation->mark();
-            c->function->mark();
-        }
+        for (unsigned local = 0, lastLocal = c->variableCount(); local < lastLocal; ++local)
+            c->locals[local].mark();
+        if (c->activation)
+            c->activation->mark();
+        c->function->mark();
     } else if (type == Type_WithContext) {
         WithContext *w = static_cast<WithContext *>(this);
         w->withObject->mark();
@@ -389,7 +386,7 @@ void ExecutionContext::setProperty(const StringRef name, const ValueRef value)
                     }
                 for (int i = (int)c->function->formalParameterCount - 1; i >= 0; --i)
                     if (c->function->formalParameterList[i]->isEqualTo(name)) {
-                        c->arguments[i] = *value;
+                        c->callData->args[i] = *value;
                         return;
                     }
                 activation = c->activation;
@@ -417,7 +414,7 @@ ReturnedValue ExecutionContext::getProperty(const StringRef name)
     name->makeIdentifier();
 
     if (name->isEqualTo(engine->id_this))
-        return thisObject.asReturnedValue();
+        return callData->thisObject.asReturnedValue();
 
     bool hasWith = false;
     bool hasCatchScope = false;
@@ -449,7 +446,7 @@ ReturnedValue ExecutionContext::getProperty(const StringRef name)
                         return c->locals[i].asReturnedValue();
                 for (int i = (int)f->formalParameterCount - 1; i >= 0; --i)
                     if (f->formalParameterList[i]->isEqualTo(name))
-                        return c->arguments[i].asReturnedValue();
+                        return c->callData->args[i].asReturnedValue();
             }
             if (c->activation) {
                 bool hasProperty = false;
@@ -482,7 +479,7 @@ ReturnedValue ExecutionContext::getPropertyNoThrow(const StringRef name)
     name->makeIdentifier();
 
     if (name->isEqualTo(engine->id_this))
-        return thisObject.asReturnedValue();
+        return callData->thisObject.asReturnedValue();
 
     bool hasWith = false;
     bool hasCatchScope = false;
@@ -514,7 +511,7 @@ ReturnedValue ExecutionContext::getPropertyNoThrow(const StringRef name)
                         return c->locals[i].asReturnedValue();
                 for (int i = (int)f->formalParameterCount - 1; i >= 0; --i)
                     if (f->formalParameterList[i]->isEqualTo(name))
-                        return c->arguments[i].asReturnedValue();
+                        return c->callData->args[i].asReturnedValue();
             }
             if (c->activation) {
                 bool hasProperty = false;
@@ -546,7 +543,7 @@ ReturnedValue ExecutionContext::getPropertyAndBase(const StringRef name, Object
     name->makeIdentifier();
 
     if (name->isEqualTo(engine->id_this))
-        return thisObject.asReturnedValue();
+        return callData->thisObject.asReturnedValue();
 
     bool hasWith = false;
     bool hasCatchScope = false;
@@ -579,7 +576,7 @@ ReturnedValue ExecutionContext::getPropertyAndBase(const StringRef name, Object
                         return c->locals[i].asReturnedValue();
                 for (int i = (int)f->formalParameterCount - 1; i >= 0; --i)
                     if (f->formalParameterList[i]->isEqualTo(name))
-                        return c->arguments[i].asReturnedValue();
+                        return c->callData->args[i].asReturnedValue();
             }
             if (c->activation) {
                 bool hasProperty = false;
@@ -695,6 +692,4 @@ void SimpleCallContext::initSimpleCallContext(ExecutionEngine *engine)
 {
     initBaseContext(Type_SimpleCallContext, engine, engine->current);
     function = 0;
-    arguments = 0;
-    argumentCount = 0;
 }
diff --git a/src/qml/jsruntime/qv4context_p.h b/src/qml/jsruntime/qv4context_p.h
index f216746212..efa7a07c1d 100644
--- a/src/qml/jsruntime/qv4context_p.h
+++ b/src/qml/jsruntime/qv4context_p.h
@@ -80,7 +80,7 @@ struct Q_QML_EXPORT ExecutionContext
     bool strictMode;
     bool marked;
 
-    Value thisObject;
+    CallData *callData;
 
     ExecutionEngine *engine;
     ExecutionContext *parent;
@@ -105,7 +105,6 @@ struct Q_QML_EXPORT ExecutionContext
         this->type = type;
         strictMode = false;
         marked = false;
-        thisObject = Value::undefinedValue();
         this->engine = engine;
         parent = parentContext;
         outer = 0;
@@ -117,7 +116,7 @@ struct Q_QML_EXPORT ExecutionContext
         interpreterInstructionPointer = 0;
     }
 
-    CallContext *newCallContext(void *stackSpace, FunctionObject *f, CallData *callData);
+    CallContext *newCallContext(void *stackSpace, Value *locals, FunctionObject *f, CallData *callData);
     CallContext *newCallContext(FunctionObject *f, CallData *callData);
     WithContext *newWithContext(Object *with);
     CatchContext *newCatchContext(String* exceptionVarName, const QV4::Value &exceptionValue);
@@ -158,13 +157,9 @@ struct SimpleCallContext : public ExecutionContext
 {
     void initSimpleCallContext(ExecutionEngine *engine);
     FunctionObject *function;
-    SafeValue *arguments;
-    unsigned int realArgumentCount;
-    unsigned int argumentCount;
+    int realArgumentCount;
 
-    ReturnedValue argument(uint i) {
-        return i < argumentCount ? arguments[i].asReturnedValue() : Value::undefinedValue().asReturnedValue();
-    }
+    inline ReturnedValue argument(int i);
 };
 
 struct CallContext : public SimpleCallContext
@@ -210,9 +205,9 @@ inline const CallContext *ExecutionContext::asCallContext() const
 
 /* Function *f, int argc */
 #define requiredMemoryForExecutionContect(f, argc) \
-    sizeof(CallContext) + sizeof(Value) * (f->varCount + qMax((uint)argc, f->formalParameterCount))
+    sizeof(CallContext) + sizeof(Value) * (f->varCount + qMax((uint)argc, f->formalParameterCount)) + sizeof(CallData)
 #define requiredMemoryForExecutionContectSimple(f) \
-    sizeof(CallContext) + sizeof(Value) * f->varCount
+    sizeof(CallContext)
 #define requiredMemoryForQmlExecutionContect(f) \
     sizeof(CallContext) + sizeof(Value) * (f->locals.size())
 #define stackContextSize (sizeof(CallContext) + 32*sizeof(Value))
diff --git a/src/qml/jsruntime/qv4dateobject.cpp b/src/qml/jsruntime/qv4dateobject.cpp
index 8bc92c6c4e..05d4b6ee7f 100644
--- a/src/qml/jsruntime/qv4dateobject.cpp
+++ b/src/qml/jsruntime/qv4dateobject.cpp
@@ -762,7 +762,7 @@ void DatePrototype::init(ExecutionEngine *engine, const Value &ctor)
 
 double DatePrototype::getThisDate(ExecutionContext *ctx)
 {
-    if (DateObject *thisObject = ctx->thisObject.asDateObject())
+    if (DateObject *thisObject = ctx->callData->thisObject.asDateObject())
         return thisObject->value.asDouble();
     else {
         ctx->throwTypeError();
@@ -772,22 +772,22 @@ double DatePrototype::getThisDate(ExecutionContext *ctx)
 
 ReturnedValue DatePrototype::method_parse(SimpleCallContext *ctx)
 {
-    if (!ctx->argumentCount)
+    if (!ctx->callData->argc)
         return Encode(qSNaN());
-    return Encode(ParseString(ctx->arguments[0].toString(ctx)->toQString()));
+    return Encode(ParseString(ctx->callData->args[0].toString(ctx)->toQString()));
 }
 
 ReturnedValue DatePrototype::method_UTC(SimpleCallContext *ctx)
 {
-    const int numArgs = ctx->argumentCount;
+    const int numArgs = ctx->callData->argc;
     if (numArgs >= 2) {
-        double year  = ctx->arguments[0].toNumber();
-        double month = ctx->arguments[1].toNumber();
-        double day   = numArgs >= 3 ? ctx->arguments[2].toNumber() : 1;
-        double hours = numArgs >= 4 ? ctx->arguments[3].toNumber() : 0;
-        double mins  = numArgs >= 5 ? ctx->arguments[4].toNumber() : 0;
-        double secs  = numArgs >= 6 ? ctx->arguments[5].toNumber() : 0;
-        double ms    = numArgs >= 7 ? ctx->arguments[6].toNumber() : 0;
+        double year  = ctx->callData->args[0].toNumber();
+        double month = ctx->callData->args[1].toNumber();
+        double day   = numArgs >= 3 ? ctx->callData->args[2].toNumber() : 1;
+        double hours = numArgs >= 4 ? ctx->callData->args[3].toNumber() : 0;
+        double mins  = numArgs >= 5 ? ctx->callData->args[4].toNumber() : 0;
+        double secs  = numArgs >= 6 ? ctx->callData->args[5].toNumber() : 0;
+        double ms    = numArgs >= 7 ? ctx->callData->args[6].toNumber() : 0;
         if (year >= 0 && year <= 99)
             year += 1900;
         double t = MakeDate(MakeDay(year, month, day),
@@ -999,11 +999,11 @@ ReturnedValue DatePrototype::method_getTimezoneOffset(SimpleCallContext *ctx)
 ReturnedValue DatePrototype::method_setTime(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<DateObject> self(scope, ctx->thisObject);
+    Scoped<DateObject> self(scope, ctx->callData->thisObject);
     if (!self)
         ctx->throwTypeError();
 
-    double t = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
+    double t = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
     self->value.setDouble(TimeClip(t));
     return self->value.asReturnedValue();
 }
@@ -1011,37 +1011,37 @@ ReturnedValue DatePrototype::method_setTime(SimpleCallContext *ctx)
 ReturnedValue DatePrototype::method_setMilliseconds(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<DateObject> self(scope, ctx->thisObject);
+    Scoped<DateObject> self(scope, ctx->callData->thisObject);
     if (!self)
         ctx->throwTypeError();
 
     double t = LocalTime(self->value.asDouble());
-    double ms = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
+    double ms = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
     self->value.setDouble(TimeClip(UTC(MakeDate(Day(t), MakeTime(HourFromTime(t), MinFromTime(t), SecFromTime(t), ms)))));
     return self->value.asReturnedValue();
 }
 
 ReturnedValue DatePrototype::method_setUTCMilliseconds(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = self->value.asDouble();
-    double ms = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
+    double ms = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
     self->value.setDouble(TimeClip(UTC(MakeDate(Day(t), MakeTime(HourFromTime(t), MinFromTime(t), SecFromTime(t), ms)))));
     return self->value.asReturnedValue();
 }
 
 ReturnedValue DatePrototype::method_setSeconds(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = LocalTime(self->value.asDouble());
-    double sec = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
-    double ms = (ctx->argumentCount < 2) ? msFromTime(t) : ctx->arguments[1].toNumber();
+    double sec = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
+    double ms = (ctx->callData->argc < 2) ? msFromTime(t) : ctx->callData->args[1].toNumber();
     t = TimeClip(UTC(MakeDate(Day(t), MakeTime(HourFromTime(t), MinFromTime(t), sec, ms))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1049,13 +1049,13 @@ ReturnedValue DatePrototype::method_setSeconds(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setUTCSeconds(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = self->value.asDouble();
-    double sec = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
-    double ms = (ctx->argumentCount < 2) ? msFromTime(t) : ctx->arguments[1].toNumber();
+    double sec = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
+    double ms = (ctx->callData->argc < 2) ? msFromTime(t) : ctx->callData->args[1].toNumber();
     t = TimeClip(UTC(MakeDate(Day(t), MakeTime(HourFromTime(t), MinFromTime(t), sec, ms))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1063,14 +1063,14 @@ ReturnedValue DatePrototype::method_setUTCSeconds(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setMinutes(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = LocalTime(self->value.asDouble());
-    double min = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
-    double sec = (ctx->argumentCount < 2) ? SecFromTime(t) : ctx->arguments[1].toNumber();
-    double ms = (ctx->argumentCount < 3) ? msFromTime(t) : ctx->arguments[2].toNumber();
+    double min = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
+    double sec = (ctx->callData->argc < 2) ? SecFromTime(t) : ctx->callData->args[1].toNumber();
+    double ms = (ctx->callData->argc < 3) ? msFromTime(t) : ctx->callData->args[2].toNumber();
     t = TimeClip(UTC(MakeDate(Day(t), MakeTime(HourFromTime(t), min, sec, ms))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1078,14 +1078,14 @@ ReturnedValue DatePrototype::method_setMinutes(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setUTCMinutes(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = self->value.asDouble();
-    double min = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
-    double sec = (ctx->argumentCount < 2) ? SecFromTime(t) : ctx->arguments[1].toNumber();
-    double ms = (ctx->argumentCount < 3) ? msFromTime(t) : ctx->arguments[2].toNumber();
+    double min = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
+    double sec = (ctx->callData->argc < 2) ? SecFromTime(t) : ctx->callData->args[1].toNumber();
+    double ms = (ctx->callData->argc < 3) ? msFromTime(t) : ctx->callData->args[2].toNumber();
     t = TimeClip(UTC(MakeDate(Day(t), MakeTime(HourFromTime(t), min, sec, ms))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1093,15 +1093,15 @@ ReturnedValue DatePrototype::method_setUTCMinutes(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setHours(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = LocalTime(self->value.asDouble());
-    double hour = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
-    double min = (ctx->argumentCount < 2) ? MinFromTime(t) : ctx->arguments[1].toNumber();
-    double sec = (ctx->argumentCount < 3) ? SecFromTime(t) : ctx->arguments[2].toNumber();
-    double ms = (ctx->argumentCount < 4) ? msFromTime(t) : ctx->arguments[3].toNumber();
+    double hour = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
+    double min = (ctx->callData->argc < 2) ? MinFromTime(t) : ctx->callData->args[1].toNumber();
+    double sec = (ctx->callData->argc < 3) ? SecFromTime(t) : ctx->callData->args[2].toNumber();
+    double ms = (ctx->callData->argc < 4) ? msFromTime(t) : ctx->callData->args[3].toNumber();
     t = TimeClip(UTC(MakeDate(Day(t), MakeTime(hour, min, sec, ms))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1109,15 +1109,15 @@ ReturnedValue DatePrototype::method_setHours(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setUTCHours(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = self->value.asDouble();
-    double hour = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
-    double min = (ctx->argumentCount < 2) ? MinFromTime(t) : ctx->arguments[1].toNumber();
-    double sec = (ctx->argumentCount < 3) ? SecFromTime(t) : ctx->arguments[2].toNumber();
-    double ms = (ctx->argumentCount < 4) ? msFromTime(t) : ctx->arguments[3].toNumber();
+    double hour = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
+    double min = (ctx->callData->argc < 2) ? MinFromTime(t) : ctx->callData->args[1].toNumber();
+    double sec = (ctx->callData->argc < 3) ? SecFromTime(t) : ctx->callData->args[2].toNumber();
+    double ms = (ctx->callData->argc < 4) ? msFromTime(t) : ctx->callData->args[3].toNumber();
     t = TimeClip(UTC(MakeDate(Day(t), MakeTime(hour, min, sec, ms))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1125,12 +1125,12 @@ ReturnedValue DatePrototype::method_setUTCHours(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setDate(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = LocalTime(self->value.asDouble());
-    double date = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
+    double date = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
     t = TimeClip(UTC(MakeDate(MakeDay(YearFromTime(t), MonthFromTime(t), date), TimeWithinDay(t))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1138,12 +1138,12 @@ ReturnedValue DatePrototype::method_setDate(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setUTCDate(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = self->value.asDouble();
-    double date = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
+    double date = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
     t = TimeClip(UTC(MakeDate(MakeDay(YearFromTime(t), MonthFromTime(t), date), TimeWithinDay(t))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1151,13 +1151,13 @@ ReturnedValue DatePrototype::method_setUTCDate(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setMonth(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = LocalTime(self->value.asDouble());
-    double month = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
-    double date = (ctx->argumentCount < 2) ? DateFromTime(t) : ctx->arguments[1].toNumber();
+    double month = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
+    double date = (ctx->callData->argc < 2) ? DateFromTime(t) : ctx->callData->args[1].toNumber();
     t = TimeClip(UTC(MakeDate(MakeDay(YearFromTime(t), month, date), TimeWithinDay(t))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1165,13 +1165,13 @@ ReturnedValue DatePrototype::method_setMonth(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setUTCMonth(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = self->value.asDouble();
-    double month = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
-    double date = (ctx->argumentCount < 2) ? DateFromTime(t) : ctx->arguments[1].toNumber();
+    double month = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
+    double date = (ctx->callData->argc < 2) ? DateFromTime(t) : ctx->callData->args[1].toNumber();
     t = TimeClip(UTC(MakeDate(MakeDay(YearFromTime(t), month, date), TimeWithinDay(t))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1179,7 +1179,7 @@ ReturnedValue DatePrototype::method_setUTCMonth(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setYear(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
@@ -1188,7 +1188,7 @@ ReturnedValue DatePrototype::method_setYear(SimpleCallContext *ctx)
         t = 0;
     else
         t = LocalTime(t);
-    double year = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
+    double year = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
     double r;
     if (std::isnan(year)) {
         r = qSNaN();
@@ -1205,14 +1205,14 @@ ReturnedValue DatePrototype::method_setYear(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setUTCFullYear(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = self->value.asDouble();
-    double year = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
-    double month = (ctx->argumentCount < 2) ? MonthFromTime(t) : ctx->arguments[1].toNumber();
-    double date = (ctx->argumentCount < 3) ? DateFromTime(t) : ctx->arguments[2].toNumber();
+    double year = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
+    double month = (ctx->callData->argc < 2) ? MonthFromTime(t) : ctx->callData->args[1].toNumber();
+    double date = (ctx->callData->argc < 3) ? DateFromTime(t) : ctx->callData->args[2].toNumber();
     t = TimeClip(UTC(MakeDate(MakeDay(year, month, date), TimeWithinDay(t))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1220,16 +1220,16 @@ ReturnedValue DatePrototype::method_setUTCFullYear(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_setFullYear(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = LocalTime(self->value.asDouble());
     if (std::isnan(t))
         t = 0;
-    double year = ctx->argumentCount ? ctx->arguments[0].toNumber() : qSNaN();
-    double month = (ctx->argumentCount < 2) ? MonthFromTime(t) : ctx->arguments[1].toNumber();
-    double date = (ctx->argumentCount < 3) ? DateFromTime(t) : ctx->arguments[2].toNumber();
+    double year = ctx->callData->argc ? ctx->callData->args[0].toNumber() : qSNaN();
+    double month = (ctx->callData->argc < 2) ? MonthFromTime(t) : ctx->callData->args[1].toNumber();
+    double date = (ctx->callData->argc < 3) ? DateFromTime(t) : ctx->callData->args[2].toNumber();
     t = TimeClip(UTC(MakeDate(MakeDay(year, month, date), TimeWithinDay(t))));
     self->value.setDouble(t);
     return self->value.asReturnedValue();
@@ -1237,7 +1237,7 @@ ReturnedValue DatePrototype::method_setFullYear(SimpleCallContext *ctx)
 
 ReturnedValue DatePrototype::method_toUTCString(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
@@ -1260,13 +1260,13 @@ static void addZeroPrefixedInt(QString &str, int num, int nDigits)
 
 ReturnedValue DatePrototype::method_toISOString(SimpleCallContext *ctx)
 {
-    DateObject *self = ctx->thisObject.asDateObject();
+    DateObject *self = ctx->callData->thisObject.asDateObject();
     if (!self)
         ctx->throwTypeError();
 
     double t = self->value.asDouble();
     if (!std::isfinite(t))
-        ctx->throwRangeError(ctx->thisObject);
+        ctx->throwRangeError(ctx->callData->thisObject);
 
     QString result;
     int year = (int)YearFromTime(t);
@@ -1299,7 +1299,7 @@ ReturnedValue DatePrototype::method_toISOString(SimpleCallContext *ctx)
 ReturnedValue DatePrototype::method_toJSON(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedValue O(scope, __qmljs_to_object(ctx, ValueRef(&ctx->thisObject)));
+    ScopedValue O(scope, __qmljs_to_object(ctx, ValueRef(&ctx->callData->thisObject)));
     ScopedValue tv(scope, __qmljs_to_primitive(O, NUMBER_HINT));
 
     if (tv->isNumber() && !std::isfinite(tv->toNumber()))
@@ -1313,7 +1313,7 @@ ReturnedValue DatePrototype::method_toJSON(SimpleCallContext *ctx)
         ctx->throwTypeError();
 
     ScopedCallData callData(scope, 0);
-    callData->thisObject = ctx->thisObject;
+    callData->thisObject = ctx->callData->thisObject;
     return toIso->call(callData);
 }
 
diff --git a/src/qml/jsruntime/qv4engine.cpp b/src/qml/jsruntime/qv4engine.cpp
index 363f0a45c0..62738c23bf 100644
--- a/src/qml/jsruntime/qv4engine.cpp
+++ b/src/qml/jsruntime/qv4engine.cpp
@@ -260,7 +260,7 @@ ExecutionEngine::ExecutionEngine(QQmlJS::EvalISelFactory *factory)
     //
     globalObject = newObject()->getPointer();
     rootContext->global = globalObject;
-    rootContext->thisObject = Value::fromObject(globalObject);
+    rootContext->callData->thisObject = Value::fromObject(globalObject);
 
     globalObject->defineDefaultProperty(QStringLiteral("Object"), objectCtor);
     globalObject->defineDefaultProperty(QStringLiteral("String"), stringCtor);
@@ -335,7 +335,7 @@ void ExecutionEngine::enableDebugger()
 
 void ExecutionEngine::initRootContext()
 {
-    rootContext = static_cast<GlobalContext *>(memoryManager->allocContext(sizeof(GlobalContext)));
+    rootContext = static_cast<GlobalContext *>(memoryManager->allocContext(sizeof(GlobalContext) + sizeof(CallData)));
     current = rootContext;
     current->parent = 0;
     rootContext->initGlobalContext(this);
diff --git a/src/qml/jsruntime/qv4errorobject.cpp b/src/qml/jsruntime/qv4errorobject.cpp
index 7ffc4feb9e..c4870e13bb 100644
--- a/src/qml/jsruntime/qv4errorobject.cpp
+++ b/src/qml/jsruntime/qv4errorobject.cpp
@@ -140,7 +140,7 @@ ErrorObject::ErrorObject(InternalClass *ic, const QString &message, const QStrin
 
 ReturnedValue ErrorObject::method_get_stack(SimpleCallContext *ctx)
 {
-    ErrorObject *This = ctx->thisObject.asErrorObject();
+    ErrorObject *This = ctx->callData->thisObject.asErrorObject();
     if (!This)
         ctx->throwTypeError();
     if (!This->stack) {
@@ -341,7 +341,7 @@ ReturnedValue ErrorPrototype::method_toString(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
 
-    Object *o = ctx->thisObject.asObject();
+    Object *o = ctx->callData->thisObject.asObject();
     if (!o)
         ctx->throwTypeError();
 
diff --git a/src/qml/jsruntime/qv4functionobject.cpp b/src/qml/jsruntime/qv4functionobject.cpp
index 6c60a9964a..7f4c419ddc 100644
--- a/src/qml/jsruntime/qv4functionobject.cpp
+++ b/src/qml/jsruntime/qv4functionobject.cpp
@@ -309,7 +309,7 @@ void FunctionPrototype::init(ExecutionEngine *engine, const Value &ctor)
 
 ReturnedValue FunctionPrototype::method_toString(SimpleCallContext *ctx)
 {
-    FunctionObject *fun = ctx->thisObject.asFunctionObject();
+    FunctionObject *fun = ctx->callData->thisObject.asFunctionObject();
     if (!fun)
         ctx->throwTypeError();
 
@@ -319,7 +319,7 @@ ReturnedValue FunctionPrototype::method_toString(SimpleCallContext *ctx)
 ReturnedValue FunctionPrototype::method_apply(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    FunctionObject *o = ctx->thisObject.asFunctionObject();
+    FunctionObject *o = ctx->callData->thisObject.asFunctionObject();
     if (!o)
         ctx->throwTypeError();
 
@@ -361,14 +361,14 @@ ReturnedValue FunctionPrototype::method_call(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
 
-    FunctionObject *o = ctx->thisObject.asFunctionObject();
+    FunctionObject *o = ctx->callData->thisObject.asFunctionObject();
     if (!o)
         ctx->throwTypeError();
 
-    ScopedCallData callData(scope, ctx->argumentCount ? ctx->argumentCount - 1 : 0);
-    if (ctx->argumentCount) {
-        std::copy(ctx->arguments + 1,
-                  ctx->arguments + ctx->argumentCount, callData->args);
+    ScopedCallData callData(scope, ctx->callData->argc ? ctx->callData->argc - 1 : 0);
+    if (ctx->callData->argc) {
+        std::copy(ctx->callData->args + 1,
+                  ctx->callData->args + ctx->callData->argc, callData->args);
     }
     callData->thisObject = ctx->argument(0);
     return o->call(callData);
@@ -377,14 +377,14 @@ ReturnedValue FunctionPrototype::method_call(SimpleCallContext *ctx)
 ReturnedValue FunctionPrototype::method_bind(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<FunctionObject> target(scope, ctx->thisObject);
+    Scoped<FunctionObject> target(scope, ctx->callData->thisObject);
     if (!target)
         ctx->throwTypeError();
 
     ScopedValue boundThis(scope, ctx->argument(0));
     QVector<Value> boundArgs;
-    for (uint i = 1; i < ctx->argumentCount; ++i)
-        boundArgs += ctx->arguments[i];
+    for (uint i = 1; i < ctx->callData->argc; ++i)
+        boundArgs += ctx->callData->args[i];
 
     return ctx->engine->newBoundFunction(ctx->engine->rootContext, target.getPointer(), boundThis, boundArgs)->asReturnedValue();
 }
@@ -469,9 +469,9 @@ ReturnedValue ScriptFunction::call(Managed *that, CallData *callData)
 
     if (!f->strictMode && !callData->thisObject.isObject()) {
         if (callData->thisObject.isNullOrUndefined()) {
-            ctx->thisObject = Value::fromObject(f->engine()->globalObject);
+            ctx->callData->thisObject = Value::fromObject(f->engine()->globalObject);
         } else {
-            ctx->thisObject = Value::fromObject(callData->thisObject.toObject(context));
+            ctx->callData->thisObject = Value::fromObject(callData->thisObject.toObject(context));
         }
     }
 
@@ -541,7 +541,7 @@ ReturnedValue SimpleScriptFunction::construct(Managed *that, CallData *callData)
     ExecutionContext *context = v4->current;
     void *stackSpace = alloca(requiredMemoryForExecutionContectSimple(f));
     callData->thisObject = obj;
-    ExecutionContext *ctx = context->newCallContext(stackSpace, f.getPointer(), callData);
+    ExecutionContext *ctx = context->newCallContext(stackSpace, scope.alloc(f->varCount), f.getPointer(), callData);
 
     try {
         Scoped<Object> result(scope, f->function->code(ctx, f->function->codeData));
@@ -558,17 +558,19 @@ ReturnedValue SimpleScriptFunction::construct(Managed *that, CallData *callData)
 
 ReturnedValue SimpleScriptFunction::call(Managed *that, CallData *callData)
 {
-    SimpleScriptFunction *f = static_cast<SimpleScriptFunction *>(that);
+    ExecutionEngine *v4 = that->engine();
+    Scope scope(v4);
+    Scoped<SimpleScriptFunction> f(scope, static_cast<SimpleScriptFunction *>(that));
+
     void *stackSpace = alloca(requiredMemoryForExecutionContectSimple(f));
-    ExecutionContext *context = f->engine()->current;
-    Scope scope(context);
-    ExecutionContext *ctx = context->newCallContext(stackSpace, f, callData);
+    ExecutionContext *context = v4->current;
+    ExecutionContext *ctx = context->newCallContext(stackSpace, scope.alloc(f->varCount), f.getPointer(), callData);
 
     if (!f->strictMode && !callData->thisObject.isObject()) {
         if (callData->thisObject.isNullOrUndefined()) {
-            ctx->thisObject = Value::fromObject(f->engine()->globalObject);
+            ctx->callData->thisObject = Value::fromObject(f->engine()->globalObject);
         } else {
-            ctx->thisObject = Value::fromObject(callData->thisObject.toObject(context));
+            ctx->callData->thisObject = Value::fromObject(callData->thisObject.toObject(context));
         }
     }
 
@@ -614,10 +616,7 @@ ReturnedValue BuiltinFunction::call(Managed *that, CallData *callData)
     SimpleCallContext ctx;
     ctx.initSimpleCallContext(f->scope->engine);
     ctx.strictMode = f->scope->strictMode; // ### needed? scope or parent context?
-    ctx.thisObject = callData->thisObject;
-    // ### const_cast
-    ctx.arguments = const_cast<SafeValue *>(callData->args);
-    ctx.argumentCount = callData->argc;
+    ctx.callData = callData;
     v4->pushContext(&ctx);
 
     ScopedValue result(scope);
@@ -642,10 +641,7 @@ ReturnedValue IndexedBuiltinFunction::call(Managed *that, CallData *callData)
     SimpleCallContext ctx;
     ctx.initSimpleCallContext(f->scope->engine);
     ctx.strictMode = f->scope->strictMode; // ### needed? scope or parent context?
-    ctx.thisObject = callData->thisObject;
-    // ### const_cast
-    ctx.arguments = const_cast<SafeValue *>(callData->args);
-    ctx.argumentCount = callData->argc;
+    ctx.callData = callData;
     v4->pushContext(&ctx);
 
     ScopedValue result(scope);
diff --git a/src/qml/jsruntime/qv4globalobject.cpp b/src/qml/jsruntime/qv4globalobject.cpp
index ae91b11991..f6f59b2f05 100644
--- a/src/qml/jsruntime/qv4globalobject.cpp
+++ b/src/qml/jsruntime/qv4globalobject.cpp
@@ -393,7 +393,7 @@ ReturnedValue EvalFunction::evalCall(Value /*thisObject*/, Value *args, int argc
     if (strictMode) {
         FunctionObject *e = FunctionObject::creatScriptFunction(ctx, function);
         ScopedCallData callData(scope, 0);
-        callData->thisObject = ctx->thisObject;
+        callData->thisObject = ctx->callData->thisObject;
         return e->call(callData);
     }
 
@@ -573,38 +573,38 @@ ReturnedValue GlobalFunctions::method_parseFloat(SimpleCallContext *ctx)
 /// isNaN [15.1.2.4]
 ReturnedValue GlobalFunctions::method_isNaN(SimpleCallContext *ctx)
 {
-    if (!ctx->argumentCount)
+    if (!ctx->callData->argc)
         // undefined gets converted to NaN
         return Encode(true);
 
-    if (ctx->arguments[0].integerCompatible())
+    if (ctx->callData->args[0].integerCompatible())
         return Encode(false);
 
-    double d = ctx->arguments[0].toNumber();
+    double d = ctx->callData->args[0].toNumber();
     return Encode((bool)std::isnan(d));
 }
 
 /// isFinite [15.1.2.5]
 ReturnedValue GlobalFunctions::method_isFinite(SimpleCallContext *ctx)
 {
-    if (!ctx->argumentCount)
+    if (!ctx->callData->argc)
         // undefined gets converted to NaN
         return Encode(false);
 
-    if (ctx->arguments[0].integerCompatible())
+    if (ctx->callData->args[0].integerCompatible())
         return Encode(true);
 
-    double d = ctx->arguments[0].toNumber();
+    double d = ctx->callData->args[0].toNumber();
     return Encode((bool)std::isfinite(d));
 }
 
 /// decodeURI [15.1.3.1]
 ReturnedValue GlobalFunctions::method_decodeURI(SimpleCallContext *context)
 {
-    if (context->argumentCount == 0)
+    if (context->callData->argc == 0)
         return Encode::undefined();
 
-    QString uriString = context->arguments[0].toString(context)->toQString();
+    QString uriString = context->callData->args[0].toString(context)->toQString();
     bool ok;
     QString out = decode(uriString, DecodeNonReserved, &ok);
     if (!ok)
@@ -616,10 +616,10 @@ ReturnedValue GlobalFunctions::method_decodeURI(SimpleCallContext *context)
 /// decodeURIComponent [15.1.3.2]
 ReturnedValue GlobalFunctions::method_decodeURIComponent(SimpleCallContext *context)
 {
-    if (context->argumentCount == 0)
+    if (context->callData->argc == 0)
         return Encode::undefined();
 
-    QString uriString = context->arguments[0].toString(context)->toQString();
+    QString uriString = context->callData->args[0].toString(context)->toQString();
     bool ok;
     QString out = decode(uriString, DecodeAll, &ok);
     if (!ok)
@@ -631,10 +631,10 @@ ReturnedValue GlobalFunctions::method_decodeURIComponent(SimpleCallContext *cont
 /// encodeURI [15.1.3.3]
 ReturnedValue GlobalFunctions::method_encodeURI(SimpleCallContext *context)
 {
-    if (context->argumentCount == 0)
+    if (context->callData->argc == 0)
         return Encode::undefined();
 
-    QString uriString = context->arguments[0].toString(context)->toQString();
+    QString uriString = context->callData->args[0].toString(context)->toQString();
     bool ok;
     QString out = encode(uriString, uriUnescapedReserved, &ok);
     if (!ok)
@@ -646,10 +646,10 @@ ReturnedValue GlobalFunctions::method_encodeURI(SimpleCallContext *context)
 /// encodeURIComponent [15.1.3.4]
 ReturnedValue GlobalFunctions::method_encodeURIComponent(SimpleCallContext *context)
 {
-    if (context->argumentCount == 0)
+    if (context->callData->argc == 0)
         return Encode::undefined();
 
-    QString uriString = context->arguments[0].toString(context)->toQString();
+    QString uriString = context->callData->args[0].toString(context)->toQString();
     bool ok;
     QString out = encode(uriString, uriUnescaped, &ok);
     if (!ok)
@@ -660,18 +660,18 @@ ReturnedValue GlobalFunctions::method_encodeURIComponent(SimpleCallContext *cont
 
 ReturnedValue GlobalFunctions::method_escape(SimpleCallContext *context)
 {
-    if (!context->argumentCount)
+    if (!context->callData->argc)
         return Value::fromString(context, QStringLiteral("undefined")).asReturnedValue();
 
-    QString str = context->arguments[0].toString(context)->toQString();
+    QString str = context->callData->args[0].toString(context)->toQString();
     return Value::fromString(context, escape(str)).asReturnedValue();
 }
 
 ReturnedValue GlobalFunctions::method_unescape(SimpleCallContext *context)
 {
-    if (!context->argumentCount)
+    if (!context->callData->argc)
         return Value::fromString(context, QStringLiteral("undefined")).asReturnedValue();
 
-    QString str = context->arguments[0].toString(context)->toQString();
+    QString str = context->callData->args[0].toString(context)->toQString();
     return Value::fromString(context, unescape(str)).asReturnedValue();
 }
diff --git a/src/qml/jsruntime/qv4include.cpp b/src/qml/jsruntime/qv4include.cpp
index d6f01bf369..bde9c23e6b 100644
--- a/src/qml/jsruntime/qv4include.cpp
+++ b/src/qml/jsruntime/qv4include.cpp
@@ -181,7 +181,7 @@ void QV4Include::finished()
 */
 QV4::ReturnedValue QV4Include::method_include(QV4::SimpleCallContext *ctx)
 {
-    if (!ctx->argumentCount)
+    if (!ctx->callData->argc)
         return QV4::Encode::undefined();
 
     QV4::ExecutionEngine *v4 = ctx->engine;
@@ -192,11 +192,11 @@ QV4::ReturnedValue QV4Include::method_include(QV4::SimpleCallContext *ctx)
     if (!context || !context->isJSContext)
         V4THROW_ERROR("Qt.include(): Can only be called from JavaScript files");
 
-    QUrl url(ctx->engine->resolvedUrl(ctx->arguments[0].toQStringNoThrow()));
+    QUrl url(ctx->engine->resolvedUrl(ctx->callData->args[0].toQStringNoThrow()));
 
     QV4::Value callbackFunction = QV4::Value::undefinedValue();
-    if (ctx->argumentCount >= 2 && ctx->arguments[1].asFunctionObject())
-        callbackFunction = ctx->arguments[1];
+    if (ctx->callData->argc >= 2 && ctx->callData->args[1].asFunctionObject())
+        callbackFunction = ctx->callData->args[1];
 
     QString localFile = QQmlFile::urlToLocalFileOrQrc(url);
 
diff --git a/src/qml/jsruntime/qv4mathobject.cpp b/src/qml/jsruntime/qv4mathobject.cpp
index 3d57b5fb2f..57a84d008a 100644
--- a/src/qml/jsruntime/qv4mathobject.cpp
+++ b/src/qml/jsruntime/qv4mathobject.cpp
@@ -98,15 +98,15 @@ static double copySign(double x, double y)
 
 ReturnedValue MathObject::method_abs(SimpleCallContext *context)
 {
-    if (!context->argumentCount)
+    if (!context->callData->argc)
         return Encode(qSNaN());
 
-    if (context->arguments[0].isInteger()) {
-        int i = context->arguments[0].integerValue();
+    if (context->callData->args[0].isInteger()) {
+        int i = context->callData->args[0].integerValue();
         return Encode(i < 0 ? - i : i);
     }
 
-    double v = context->arguments[0].toNumber();
+    double v = context->callData->args[0].toNumber();
     if (v == 0) // 0 | -0
         return Encode(0);
 
@@ -115,7 +115,7 @@ ReturnedValue MathObject::method_abs(SimpleCallContext *context)
 
 ReturnedValue MathObject::method_acos(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : 2;
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : 2;
     if (v > 1)
         return Encode(qSNaN());
 
@@ -124,7 +124,7 @@ ReturnedValue MathObject::method_acos(SimpleCallContext *context)
 
 ReturnedValue MathObject::method_asin(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : 2;
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : 2;
     if (v > 1)
         return Encode(qSNaN());
     else
@@ -133,7 +133,7 @@ ReturnedValue MathObject::method_asin(SimpleCallContext *context)
 
 ReturnedValue MathObject::method_atan(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
     if (v == 0.0)
         return Encode(v);
     else
@@ -142,8 +142,8 @@ ReturnedValue MathObject::method_atan(SimpleCallContext *context)
 
 ReturnedValue MathObject::method_atan2(SimpleCallContext *context)
 {
-    double v1 = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
-    double v2 = context->argumentCount > 1 ? context->arguments[1].toNumber() : qSNaN();
+    double v1 = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
+    double v2 = context->callData->argc > 1 ? context->callData->args[1].toNumber() : qSNaN();
 
     if ((v1 < 0) && qIsFinite(v1) && qIsInf(v2) && (copySign(1.0, v2) == 1.0))
         return Encode(copySign(0, -1.0));
@@ -160,7 +160,7 @@ ReturnedValue MathObject::method_atan2(SimpleCallContext *context)
 
 ReturnedValue MathObject::method_ceil(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
     if (v < 0.0 && v > -1.0)
         return Encode(copySign(0, -1.0));
     else
@@ -169,13 +169,13 @@ ReturnedValue MathObject::method_ceil(SimpleCallContext *context)
 
 ReturnedValue MathObject::method_cos(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
     return Encode(::cos(v));
 }
 
 ReturnedValue MathObject::method_exp(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
     if (qIsInf(v)) {
         if (copySign(1.0, v) == -1.0)
             return Encode(0);
@@ -188,13 +188,13 @@ ReturnedValue MathObject::method_exp(SimpleCallContext *context)
 
 ReturnedValue MathObject::method_floor(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
     return Encode(::floor(v));
 }
 
 ReturnedValue MathObject::method_log(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
     if (v < 0)
         return Encode(qSNaN());
     else
@@ -204,8 +204,8 @@ ReturnedValue MathObject::method_log(SimpleCallContext *context)
 ReturnedValue MathObject::method_max(SimpleCallContext *context)
 {
     double mx = -qInf();
-    for (unsigned i = 0; i < context->argumentCount; ++i) {
-        double x = context->arguments[i].toNumber();
+    for (unsigned i = 0; i < context->callData->argc; ++i) {
+        double x = context->callData->args[i].toNumber();
         if (x > mx || std::isnan(x))
             mx = x;
     }
@@ -215,8 +215,8 @@ ReturnedValue MathObject::method_max(SimpleCallContext *context)
 ReturnedValue MathObject::method_min(SimpleCallContext *context)
 {
     double mx = qInf();
-    for (unsigned i = 0; i < context->argumentCount; ++i) {
-        double x = context->arguments[i].toNumber();
+    for (unsigned i = 0; i < context->callData->argc; ++i) {
+        double x = context->callData->args[i].toNumber();
         if ((x == 0 && mx == x && copySign(1.0, x) == -1.0)
                 || (x < mx) || std::isnan(x)) {
             mx = x;
@@ -227,8 +227,8 @@ ReturnedValue MathObject::method_min(SimpleCallContext *context)
 
 ReturnedValue MathObject::method_pow(SimpleCallContext *context)
 {
-    double x = context->argumentCount > 0 ? context->arguments[0].toNumber() : qSNaN();
-    double y = context->argumentCount > 1 ? context->arguments[1].toNumber() : qSNaN();
+    double x = context->callData->argc > 0 ? context->callData->args[0].toNumber() : qSNaN();
+    double y = context->callData->argc > 1 ? context->callData->args[1].toNumber() : qSNaN();
 
     if (std::isnan(y))
         return Encode(qSNaN());
@@ -282,26 +282,26 @@ ReturnedValue MathObject::method_random(SimpleCallContext *)
 
 ReturnedValue MathObject::method_round(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
     v = copySign(::floor(v + 0.5), v);
     return Encode(v);
 }
 
 ReturnedValue MathObject::method_sin(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
     return Encode(::sin(v));
 }
 
 ReturnedValue MathObject::method_sqrt(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
     return Encode(::sqrt(v));
 }
 
 ReturnedValue MathObject::method_tan(SimpleCallContext *context)
 {
-    double v = context->argumentCount ? context->arguments[0].toNumber() : qSNaN();
+    double v = context->callData->argc ? context->callData->args[0].toNumber() : qSNaN();
     if (v == 0.0)
         return Encode(v);
     else
diff --git a/src/qml/jsruntime/qv4numberobject.cpp b/src/qml/jsruntime/qv4numberobject.cpp
index f946b3180a..bc5e225f9b 100644
--- a/src/qml/jsruntime/qv4numberobject.cpp
+++ b/src/qml/jsruntime/qv4numberobject.cpp
@@ -100,9 +100,9 @@ void NumberPrototype::init(ExecutionEngine *engine, const Value &ctor)
 
 inline Value thisNumberValue(ExecutionContext *ctx)
 {
-    if (ctx->thisObject.isNumber())
-        return ctx->thisObject;
-    NumberObject *n = ctx->thisObject.asNumberObject();
+    if (ctx->callData->thisObject.isNumber())
+        return ctx->callData->thisObject;
+    NumberObject *n = ctx->callData->thisObject.asNumberObject();
     if (!n)
         ctx->throwTypeError();
     return n->value;
@@ -112,8 +112,8 @@ ReturnedValue NumberPrototype::method_toString(SimpleCallContext *ctx)
 {
     double num = thisNumberValue(ctx).asDouble();
 
-    if (ctx->argumentCount && !ctx->arguments[0].isUndefined()) {
-        int radix = ctx->arguments[0].toInt32();
+    if (ctx->callData->argc && !ctx->callData->args[0].isUndefined()) {
+        int radix = ctx->callData->args[0].toInt32();
         if (radix < 2 || radix > 36) {
             ctx->throwError(QString::fromLatin1("Number.prototype.toString: %0 is not a valid radix")
                             .arg(radix));
@@ -180,14 +180,14 @@ ReturnedValue NumberPrototype::method_toFixed(SimpleCallContext *ctx)
 
     double fdigits = 0;
 
-    if (ctx->argumentCount > 0)
-        fdigits = ctx->arguments[0].toInteger();
+    if (ctx->callData->argc > 0)
+        fdigits = ctx->callData->args[0].toInteger();
 
     if (std::isnan(fdigits))
         fdigits = 0;
 
     if (fdigits < 0 || fdigits > 20)
-        ctx->throwRangeError(ctx->thisObject);
+        ctx->throwRangeError(ctx->callData->thisObject);
 
     QString str;
     if (std::isnan(v))
@@ -207,8 +207,8 @@ ReturnedValue NumberPrototype::method_toExponential(SimpleCallContext *ctx)
 
     int fdigits = -1;
 
-    if (ctx->argumentCount && !ctx->arguments[0].isUndefined()) {
-        int fdigits = ctx->arguments[0].toInt32();
+    if (ctx->callData->argc && !ctx->callData->args[0].isUndefined()) {
+        int fdigits = ctx->callData->args[0].toInt32();
         if (fdigits < 0 || fdigits > 20) {
             String *error = ctx->engine->newString(QStringLiteral("Number.prototype.toExponential: fractionDigits out of range"));
             ctx->throwRangeError(Value::fromString(error));
@@ -229,10 +229,10 @@ ReturnedValue NumberPrototype::method_toPrecision(SimpleCallContext *ctx)
 
     ScopedValue v(scope, thisNumberValue(ctx));
 
-    if (!ctx->argumentCount || ctx->arguments[0].isUndefined())
+    if (!ctx->callData->argc || ctx->callData->args[0].isUndefined())
         return __qmljs_to_string(v, ctx);
 
-    double precision = ctx->arguments[0].toInt32();
+    double precision = ctx->callData->args[0].toInt32();
     if (precision < 1 || precision > 21) {
         String *error = ctx->engine->newString(QStringLiteral("Number.prototype.toPrecision: precision out of range"));
         ctx->throwRangeError(Value::fromString(error));
diff --git a/src/qml/jsruntime/qv4objectproto.cpp b/src/qml/jsruntime/qv4objectproto.cpp
index befc01936d..96426cabfb 100644
--- a/src/qml/jsruntime/qv4objectproto.cpp
+++ b/src/qml/jsruntime/qv4objectproto.cpp
@@ -169,7 +169,7 @@ ReturnedValue ObjectPrototype::method_getOwnPropertyNames(SimpleCallContext *con
     if (!O)
         context->throwTypeError();
 
-    ScopedArrayObject array(scope, getOwnPropertyNames(context->engine, context->arguments[0]));
+    ScopedArrayObject array(scope, getOwnPropertyNames(context->engine, context->callData->args[0]));
     return array.asReturnedValue();
 }
 
@@ -183,8 +183,8 @@ ReturnedValue ObjectPrototype::method_create(SimpleCallContext *ctx)
     Scoped<Object> newObject(scope, ctx->engine->newObject());
     newObject->setPrototype(O->asObject());
 
-    if (ctx->argumentCount > 1 && !ctx->arguments[1].isUndefined()) {
-        ctx->arguments[0] = newObject.asValue();
+    if (ctx->callData->argc > 1 && !ctx->callData->args[1].isUndefined()) {
+        ctx->callData->args[0] = newObject.asValue();
         return method_defineProperties(ctx);
     }
 
@@ -387,12 +387,12 @@ ReturnedValue ObjectPrototype::method_keys(SimpleCallContext *ctx)
 ReturnedValue ObjectPrototype::method_toString(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    if (ctx->thisObject.isUndefined()) {
+    if (ctx->callData->thisObject.isUndefined()) {
         return Value::fromString(ctx, QStringLiteral("[object Undefined]")).asReturnedValue();
-    } else if (ctx->thisObject.isNull()) {
+    } else if (ctx->callData->thisObject.isNull()) {
         return Value::fromString(ctx, QStringLiteral("[object Null]")).asReturnedValue();
     } else {
-        ScopedObject obj(scope, __qmljs_to_object(ctx, ValueRef(&ctx->thisObject)));
+        ScopedObject obj(scope, __qmljs_to_object(ctx, ValueRef(&ctx->callData->thisObject)));
         QString className = obj->className();
         return Value::fromString(ctx, QString::fromUtf8("[object %1]").arg(className)).asReturnedValue();
     }
@@ -401,7 +401,7 @@ ReturnedValue ObjectPrototype::method_toString(SimpleCallContext *ctx)
 ReturnedValue ObjectPrototype::method_toLocaleString(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedObject o(scope, ctx->thisObject.toObject(ctx));
+    ScopedObject o(scope, ctx->callData->thisObject.toObject(ctx));
     Scoped<FunctionObject> f(scope, o->get(ctx->engine->id_toString));
     if (!f)
         ctx->throwTypeError();
@@ -412,14 +412,14 @@ ReturnedValue ObjectPrototype::method_toLocaleString(SimpleCallContext *ctx)
 
 ReturnedValue ObjectPrototype::method_valueOf(SimpleCallContext *ctx)
 {
-    return Value::fromObject(ctx->thisObject.toObject(ctx)).asReturnedValue();
+    return Value::fromObject(ctx->callData->thisObject.toObject(ctx)).asReturnedValue();
 }
 
 ReturnedValue ObjectPrototype::method_hasOwnProperty(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
     Scoped<String> P(scope, ctx->argument(0), Scoped<String>::Convert);
-    Scoped<Object> O(scope, ctx->thisObject, Scoped<Object>::Convert);
+    Scoped<Object> O(scope, ctx->callData->thisObject, Scoped<Object>::Convert);
     bool r = O->__getOwnProperty__(P) != 0;
     if (!r)
         r = !O->query(P).isEmpty();
@@ -433,7 +433,7 @@ ReturnedValue ObjectPrototype::method_isPrototypeOf(SimpleCallContext *ctx)
     if (!V)
         return Encode(false);
 
-    Scoped<Object> O(scope, ctx->thisObject, Scoped<Object>::Convert);
+    Scoped<Object> O(scope, ctx->callData->thisObject, Scoped<Object>::Convert);
     Scoped<Object> proto(scope, V->prototype());
     while (proto) {
         if (O.getPointer() == proto.getPointer())
@@ -448,7 +448,7 @@ ReturnedValue ObjectPrototype::method_propertyIsEnumerable(SimpleCallContext *ct
     Scope scope(ctx);
     Scoped<String> p(scope, ctx->argument(0), Scoped<String>::Convert);
 
-    Scoped<Object> o(scope, ctx->thisObject, Scoped<Object>::Convert);
+    Scoped<Object> o(scope, ctx->callData->thisObject, Scoped<Object>::Convert);
     PropertyAttributes attrs;
     o->__getOwnProperty__(p, &attrs);
     return Encode(attrs.isEnumerable());
@@ -456,7 +456,7 @@ ReturnedValue ObjectPrototype::method_propertyIsEnumerable(SimpleCallContext *ct
 
 ReturnedValue ObjectPrototype::method_defineGetter(SimpleCallContext *ctx)
 {
-    if (ctx->argumentCount < 2)
+    if (ctx->callData->argc < 2)
         ctx->throwTypeError();
 
     Scope scope(ctx);
@@ -466,9 +466,9 @@ ReturnedValue ObjectPrototype::method_defineGetter(SimpleCallContext *ctx)
     if (!f)
         ctx->throwTypeError();
 
-    Scoped<Object> o(scope, ctx->thisObject);
+    Scoped<Object> o(scope, ctx->callData->thisObject);
     if (!o) {
-        if (!ctx->thisObject.isUndefined())
+        if (!ctx->callData->thisObject.isUndefined())
             return Encode::undefined();
         o = ctx->engine->globalObject;
     }
@@ -480,7 +480,7 @@ ReturnedValue ObjectPrototype::method_defineGetter(SimpleCallContext *ctx)
 
 ReturnedValue ObjectPrototype::method_defineSetter(SimpleCallContext *ctx)
 {
-    if (ctx->argumentCount < 2)
+    if (ctx->callData->argc < 2)
         ctx->throwTypeError();
 
     Scope scope(ctx);
@@ -490,9 +490,9 @@ ReturnedValue ObjectPrototype::method_defineSetter(SimpleCallContext *ctx)
     if (!f)
         ctx->throwTypeError();
 
-    Scoped<Object> o(scope, ctx->thisObject);
+    Scoped<Object> o(scope, ctx->callData->thisObject);
     if (!o) {
-        if (!ctx->thisObject.isUndefined())
+        if (!ctx->callData->thisObject.isUndefined())
             return Encode::undefined();
         o = ctx->engine->globalObject;
     }
@@ -505,7 +505,7 @@ ReturnedValue ObjectPrototype::method_defineSetter(SimpleCallContext *ctx)
 ReturnedValue ObjectPrototype::method_get_proto(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    ScopedObject o(scope, ctx->thisObject.asObject());
+    ScopedObject o(scope, ctx->callData->thisObject.asObject());
     if (!o)
         ctx->throwTypeError();
 
@@ -515,16 +515,16 @@ ReturnedValue ObjectPrototype::method_get_proto(SimpleCallContext *ctx)
 ReturnedValue ObjectPrototype::method_set_proto(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    Scoped<Object> o(scope, ctx->thisObject);
-    if (!o || !ctx->argumentCount)
+    Scoped<Object> o(scope, ctx->callData->thisObject);
+    if (!o || !ctx->callData->argc)
         ctx->throwTypeError();
 
-    if (ctx->arguments[0].isNull()) {
+    if (ctx->callData->args[0].isNull()) {
         o->setPrototype(0);
         return Encode::undefined();
     }
 
-    Scoped<Object> p(scope, ctx->arguments[0]);
+    Scoped<Object> p(scope, ctx->callData->args[0]);
     bool ok = false;
     if (!!p) {
         if (o->prototype() == p.getPointer()) {
diff --git a/src/qml/jsruntime/qv4qobjectwrapper.cpp b/src/qml/jsruntime/qv4qobjectwrapper.cpp
index b7a696cc33..876bda3163 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper.cpp
+++ b/src/qml/jsruntime/qv4qobjectwrapper.cpp
@@ -788,10 +788,10 @@ struct QObjectSlotDispatcher : public QtPrivate::QSlotObjectBase
 
 ReturnedValue QObjectWrapper::method_connect(SimpleCallContext *ctx)
 {
-    if (ctx->argumentCount == 0)
+    if (ctx->callData->argc == 0)
         V4THROW_ERROR("Function.prototype.connect: no arguments given");
 
-    QPair<QObject *, int> signalInfo = extractQtSignal(ctx->thisObject);
+    QPair<QObject *, int> signalInfo = extractQtSignal(ctx->callData->thisObject);
     QObject *signalObject = signalInfo.first;
     int signalIndex = signalInfo.second;
 
@@ -808,11 +808,11 @@ ReturnedValue QObjectWrapper::method_connect(SimpleCallContext *ctx)
     QV4::ScopedFunctionObject f(scope);
     QV4::ScopedValue thisObject (scope, QV4::Encode::undefined());
 
-    if (ctx->argumentCount == 1) {
-        f = ctx->arguments[0];
-    } else if (ctx->argumentCount >= 2) {
-        thisObject = ctx->arguments[0];
-        f = ctx->arguments[1];
+    if (ctx->callData->argc == 1) {
+        f = ctx->callData->args[0];
+    } else if (ctx->callData->argc >= 2) {
+        thisObject = ctx->callData->args[0];
+        f = ctx->callData->args[1];
     }
 
     if (!f)
@@ -834,10 +834,10 @@ ReturnedValue QObjectWrapper::method_connect(SimpleCallContext *ctx)
 
 ReturnedValue QObjectWrapper::method_disconnect(SimpleCallContext *ctx)
 {
-    if (ctx->argumentCount == 0)
+    if (ctx->callData->argc == 0)
         V4THROW_ERROR("Function.prototype.disconnect: no arguments given");
 
-    QPair<QObject *, int> signalInfo = extractQtSignal(ctx->thisObject);
+    QPair<QObject *, int> signalInfo = extractQtSignal(ctx->callData->thisObject);
     QObject *signalObject = signalInfo.first;
     int signalIndex = signalInfo.second;
 
@@ -853,11 +853,11 @@ ReturnedValue QObjectWrapper::method_disconnect(SimpleCallContext *ctx)
     QV4::Value functionValue = QV4::Value::undefinedValue();
     QV4::Value functionThisValue = QV4::Value::undefinedValue();
 
-    if (ctx->argumentCount == 1) {
-        functionValue = ctx->arguments[0];
-    } else if (ctx->argumentCount >= 2) {
-        functionThisValue = ctx->arguments[0];
-        functionValue = ctx->arguments[1];
+    if (ctx->callData->argc == 1) {
+        functionValue = ctx->callData->args[0];
+    } else if (ctx->callData->argc >= 2) {
+        functionThisValue = ctx->callData->args[0];
+        functionValue = ctx->callData->args[1];
     }
 
     if (!functionValue.asFunctionObject())
diff --git a/src/qml/jsruntime/qv4regexpobject.cpp b/src/qml/jsruntime/qv4regexpobject.cpp
index 3f58f28b4b..fee66d9d09 100644
--- a/src/qml/jsruntime/qv4regexpobject.cpp
+++ b/src/qml/jsruntime/qv4regexpobject.cpp
@@ -303,8 +303,7 @@ void RegExpPrototype::init(ExecutionEngine *engine, const Value &ctor)
 ReturnedValue RegExpPrototype::method_exec(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-
-    RegExpObject *r = ctx->thisObject.as<RegExpObject>();
+    Scoped<RegExpObject> r(scope, ctx->callData->thisObject.as<RegExpObject>());
     if (!r)
         ctx->throwTypeError();
 
@@ -355,7 +354,8 @@ ReturnedValue RegExpPrototype::method_test(SimpleCallContext *ctx)
 
 ReturnedValue RegExpPrototype::method_toString(SimpleCallContext *ctx)
 {
-    RegExpObject *r = ctx->thisObject.as<RegExpObject>();
+    Scope scope(ctx);
+    Scoped<RegExpObject> r(scope, ctx->callData->thisObject.as<RegExpObject>());
     if (!r)
         ctx->throwTypeError();
 
@@ -365,12 +365,12 @@ ReturnedValue RegExpPrototype::method_toString(SimpleCallContext *ctx)
 ReturnedValue RegExpPrototype::method_compile(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
-    RegExpObject *r = ctx->thisObject.as<RegExpObject>();
+    Scoped<RegExpObject> r(scope, ctx->callData->thisObject.as<RegExpObject>());
     if (!r)
         ctx->throwTypeError();
 
-    ScopedCallData callData(scope, ctx->argumentCount);
-    memcpy(callData->args, ctx->arguments, ctx->argumentCount*sizeof(Value));
+    ScopedCallData callData(scope, ctx->callData->argc);
+    memcpy(callData->args, ctx->callData->args, ctx->callData->argc*sizeof(Value));
     RegExpObject *re = Value::fromReturnedValue(ctx->engine->regExpCtor.asFunctionObject()->construct(callData)).as<RegExpObject>();
 
     r->value = re->value;
diff --git a/src/qml/jsruntime/qv4scopedvalue_p.h b/src/qml/jsruntime/qv4scopedvalue_p.h
index a8e18dac78..30a9aa8b38 100644
--- a/src/qml/jsruntime/qv4scopedvalue_p.h
+++ b/src/qml/jsruntime/qv4scopedvalue_p.h
@@ -60,13 +60,13 @@ struct Scope {
         , size(0)
 #endif
     {
-        mark = ctx->engine->jsStackTop;
+        mark = engine->jsStackTop;
     }
 
     explicit Scope(ExecutionEngine *e)
         : engine(e)
     {
-        mark = e->jsStackTop;
+        mark = engine->jsStackTop;
     }
 
     ~Scope() {
@@ -77,6 +77,15 @@ struct Scope {
         engine->jsStackTop = mark;
     }
 
+    Value *alloc(int nValues) {
+        Value *ptr = engine->jsStackTop;
+        engine->jsStackTop += nValues;
+#ifndef QT_NO_DEBUG
+        size += nValues;
+#endif
+        return ptr;
+    }
+
     ExecutionEngine *engine;
     Value *mark;
 #ifndef QT_NO_DEBUG
@@ -683,6 +692,10 @@ inline WeakValue &WeakValue::operator=(Returned<T> *obj)
     return operator=(QV4::Value::fromManaged(obj->getPointer()).asReturnedValue());
 }
 
+inline ReturnedValue SimpleCallContext::argument(int i) {
+    return i < callData->argc ? callData->args[i].asReturnedValue() : Value::undefinedValue().asReturnedValue();
+}
+
 
 }
 
diff --git a/src/qml/jsruntime/qv4sequenceobject.cpp b/src/qml/jsruntime/qv4sequenceobject.cpp
index e8ba80de35..6ad13efbdd 100644
--- a/src/qml/jsruntime/qv4sequenceobject.cpp
+++ b/src/qml/jsruntime/qv4sequenceobject.cpp
@@ -376,8 +376,8 @@ public:
             loadReference();
         }
 
-        if (ctx->argumentCount == 1 && ctx->arguments[0].asFunctionObject()) {
-            QV4::Value compareFn = ctx->arguments[0];
+        if (ctx->callData->argc == 1 && ctx->callData->args[0].asFunctionObject()) {
+            QV4::Value compareFn = ctx->callData->args[0];
             CompareFunctor cf(ctx, compareFn);
             std::sort(m_container.begin(), m_container.end(), cf);
         } else {
@@ -391,7 +391,8 @@ public:
 
     static QV4::ReturnedValue method_get_length(QV4::SimpleCallContext *ctx)
     {
-        QQmlSequence<Container> *This = ctx->thisObject.as<QQmlSequence<Container> >();
+        QV4::Scope scope(ctx);
+        QV4::Scoped<QQmlSequence<Container> > This(scope, ctx->callData->thisObject.as<QQmlSequence<Container> >());
         if (!This)
             ctx->throwTypeError();
 
@@ -405,11 +406,12 @@ public:
 
     static QV4::ReturnedValue method_set_length(QV4::SimpleCallContext* ctx)
     {
-        QQmlSequence<Container> *This = ctx->thisObject.as<QQmlSequence<Container> >();
+        QV4::Scope scope(ctx);
+        QV4::Scoped<QQmlSequence<Container> > This(scope, ctx->callData->thisObject.as<QQmlSequence<Container> >());
         if (!This)
             ctx->throwTypeError();
 
-        quint32 newLength = ctx->arguments[0].toUInt32();
+        quint32 newLength = ctx->callData->args[0].toUInt32();
         /* Qt containers have int (rather than uint) allowable indexes. */
         if (newLength > INT_MAX) {
             generateWarning(ctx, QLatin1String("Index out of range during length set"));
@@ -542,12 +544,12 @@ void SequencePrototype::init()
 
 QV4::ReturnedValue SequencePrototype::method_sort(QV4::SimpleCallContext *ctx)
 {
-    QV4::Object *o = ctx->thisObject.asObject();
+    QV4::Object *o = ctx->callData->thisObject.asObject();
     if (!o || !o->isListType())
         ctx->throwTypeError();
 
-    if (ctx->argumentCount >= 2)
-        return ctx->thisObject.asReturnedValue();
+    if (ctx->callData->argc >= 2)
+        return ctx->callData->thisObject.asReturnedValue();
 
 #define CALL_SORT(SequenceElementType, SequenceElementTypeName, SequenceType, DefaultValue) \
         if (QQml##SequenceElementTypeName##List *s = o->as<QQml##SequenceElementTypeName##List>()) { \
@@ -557,7 +559,7 @@ QV4::ReturnedValue SequencePrototype::method_sort(QV4::SimpleCallContext *ctx)
         FOREACH_QML_SEQUENCE_TYPE(CALL_SORT)
 
 #undef CALL_SORT
-    return ctx->thisObject.asReturnedValue();
+    return ctx->callData->thisObject.asReturnedValue();
 }
 
 #define IS_SEQUENCE(unused1, unused2, SequenceType, unused3) \
diff --git a/src/qml/jsruntime/qv4sequenceobject_p.h b/src/qml/jsruntime/qv4sequenceobject_p.h
index ca58b11090..a743bac247 100644
--- a/src/qml/jsruntime/qv4sequenceobject_p.h
+++ b/src/qml/jsruntime/qv4sequenceobject_p.h
@@ -71,7 +71,7 @@ struct SequencePrototype : public QV4::Object
 
     static ReturnedValue method_valueOf(QV4::SimpleCallContext *ctx)
     {
-        return QV4::Value::fromString(ctx->thisObject.toString(ctx)).asReturnedValue();
+        return QV4::Value::fromString(ctx->callData->thisObject.toString(ctx)).asReturnedValue();
     }
 
     static ReturnedValue method_sort(QV4::SimpleCallContext *ctx);
diff --git a/src/qml/jsruntime/qv4stringobject.cpp b/src/qml/jsruntime/qv4stringobject.cpp
index a7343bc8c1..05a1ef4100 100644
--- a/src/qml/jsruntime/qv4stringobject.cpp
+++ b/src/qml/jsruntime/qv4stringobject.cpp
@@ -218,7 +218,7 @@ void StringPrototype::init(ExecutionEngine *engine, const Value &ctor)
 static QString getThisString(ExecutionContext *ctx)
 {
     Scope scope(ctx);
-    ScopedValue t(scope, ctx->thisObject);
+    ScopedValue t(scope, ctx->callData->thisObject);
     if (t->isString())
         return t->stringValue()->toQString();
     if (StringObject *thisString = t->asStringObject())
@@ -230,10 +230,10 @@ static QString getThisString(ExecutionContext *ctx)
 
 ReturnedValue StringPrototype::method_toString(SimpleCallContext *context)
 {
-    if (context->thisObject.isString())
-        return context->thisObject.asReturnedValue();
+    if (context->callData->thisObject.isString())
+        return context->callData->thisObject.asReturnedValue();
 
-    StringObject *o = context->thisObject.asStringObject();
+    StringObject *o = context->callData->thisObject.asStringObject();
     if (!o)
         context->throwTypeError();
     return o->value.asReturnedValue();
@@ -244,8 +244,8 @@ ReturnedValue StringPrototype::method_charAt(SimpleCallContext *context)
     const QString str = getThisString(context);
 
     int pos = 0;
-    if (context->argumentCount > 0)
-        pos = (int) context->arguments[0].toInteger();
+    if (context->callData->argc > 0)
+        pos = (int) context->callData->args[0].toInteger();
 
     QString result;
     if (pos >= 0 && pos < str.length())
@@ -259,8 +259,8 @@ ReturnedValue StringPrototype::method_charCodeAt(SimpleCallContext *context)
     const QString str = getThisString(context);
 
     int pos = 0;
-    if (context->argumentCount > 0)
-        pos = (int) context->arguments[0].toInteger();
+    if (context->callData->argc > 0)
+        pos = (int) context->callData->args[0].toInteger();
 
 
     if (pos >= 0 && pos < str.length())
@@ -276,8 +276,8 @@ ReturnedValue StringPrototype::method_concat(SimpleCallContext *context)
     QString value = getThisString(context);
 
     ScopedValue v(scope);
-    for (int i = 0; i < context->argumentCount; ++i) {
-        v = __qmljs_to_string(ValueRef(&context->arguments[i]), context);
+    for (int i = 0; i < context->callData->argc; ++i) {
+        v = __qmljs_to_string(ValueRef(&context->callData->args[i]), context);
         assert(v->isString());
         value += v->stringValue()->toQString();
     }
@@ -290,12 +290,12 @@ ReturnedValue StringPrototype::method_indexOf(SimpleCallContext *context)
     QString value = getThisString(context);
 
     QString searchString;
-    if (context->argumentCount)
-        searchString = context->arguments[0].toString(context)->toQString();
+    if (context->callData->argc)
+        searchString = context->callData->args[0].toString(context)->toQString();
 
     int pos = 0;
-    if (context->argumentCount > 1)
-        pos = (int) context->arguments[1].toInteger();
+    if (context->callData->argc > 1)
+        pos = (int) context->callData->args[1].toInteger();
 
     int index = -1;
     if (! value.isEmpty())
@@ -311,8 +311,8 @@ ReturnedValue StringPrototype::method_lastIndexOf(SimpleCallContext *context)
     const QString value = getThisString(context);
 
     QString searchString;
-    if (context->argumentCount)
-        searchString = context->arguments[0].toQString();
+    if (context->callData->argc)
+        searchString = context->callData->args[0].toQString();
 
     ScopedValue posArg(scope, context->argument(1));
     double position = __qmljs_to_number(posArg);
@@ -333,19 +333,19 @@ ReturnedValue StringPrototype::method_lastIndexOf(SimpleCallContext *context)
 ReturnedValue StringPrototype::method_localeCompare(SimpleCallContext *context)
 {
     const QString value = getThisString(context);
-    const QString that = (context->argumentCount ? context->arguments[0] : Value::undefinedValue()).toQString();
+    const QString that = (context->callData->argc ? context->callData->args[0] : Value::undefinedValue()).toQString();
     return Encode(QString::localeAwareCompare(value, that));
 }
 
 ReturnedValue StringPrototype::method_match(SimpleCallContext *context)
 {
-    if (context->thisObject.isUndefined() || context->thisObject.isNull())
+    if (context->callData->thisObject.isUndefined() || context->callData->thisObject.isNull())
         context->throwTypeError();
 
     Scope scope(context);
-    ScopedString s(scope, context->thisObject.toString(context));
+    ScopedString s(scope, context->callData->thisObject.toString(context));
 
-    ScopedValue regexp(scope, context->argumentCount ? context->arguments[0] : Value::undefinedValue());
+    ScopedValue regexp(scope, context->callData->argc ? context->callData->args[0] : Value::undefinedValue());
     Scoped<RegExpObject> rx(scope, regexp);
     if (!rx) {
         ScopedCallData callData(scope, 1);
@@ -451,10 +451,10 @@ ReturnedValue StringPrototype::method_replace(SimpleCallContext *ctx)
 {
     Scope scope(ctx);
     QString string;
-    if (StringObject *thisString = ctx->thisObject.asStringObject())
+    if (StringObject *thisString = ctx->callData->thisObject.asStringObject())
         string = thisString->value.stringValue()->toQString();
     else
-        string = ctx->thisObject.toString(ctx)->toQString();
+        string = ctx->callData->thisObject.toString(ctx)->toQString();
 
     int numCaptures = 0;
     int numStringMatches = 0;
@@ -585,9 +585,9 @@ ReturnedValue StringPrototype::method_slice(SimpleCallContext *ctx)
     const QString text = getThisString(ctx);
     const double length = text.length();
 
-    double start = ctx->argumentCount ? ctx->arguments[0].toInteger() : 0;
-    double end = (ctx->argumentCount < 2 || ctx->arguments[1].isUndefined())
-            ? length : ctx->arguments[1].toInteger();
+    double start = ctx->callData->argc ? ctx->callData->args[0].toInteger() : 0;
+    double end = (ctx->callData->argc < 2 || ctx->callData->args[1].isUndefined())
+            ? length : ctx->callData->args[1].toInteger();
 
     if (start < 0)
         start = qMax(length + start, 0.);
@@ -690,12 +690,12 @@ ReturnedValue StringPrototype::method_substr(SimpleCallContext *context)
     const QString value = getThisString(context);
 
     double start = 0;
-    if (context->argumentCount > 0)
-        start = context->arguments[0].toInteger();
+    if (context->callData->argc > 0)
+        start = context->callData->args[0].toInteger();
 
     double length = +qInf();
-    if (context->argumentCount > 1)
-        length = context->arguments[1].toInteger();
+    if (context->callData->argc > 1)
+        length = context->callData->args[1].toInteger();
 
     double count = value.length();
     if (start < 0)
@@ -716,8 +716,8 @@ ReturnedValue StringPrototype::method_substring(SimpleCallContext *context)
     double start = 0;
     double end = length;
 
-    if (context->argumentCount > 0)
-        start = context->arguments[0].toInteger();
+    if (context->callData->argc > 0)
+        start = context->callData->args[0].toInteger();
 
     Scope scope(context);
     ScopedValue endValue(scope, context->argument(1));
@@ -771,10 +771,10 @@ ReturnedValue StringPrototype::method_toLocaleUpperCase(SimpleCallContext *ctx)
 
 ReturnedValue StringPrototype::method_fromCharCode(SimpleCallContext *context)
 {
-    QString str(context->argumentCount, Qt::Uninitialized);
+    QString str(context->callData->argc, Qt::Uninitialized);
     QChar *ch = str.data();
-    for (int i = 0; i < context->argumentCount; ++i) {
-        *ch = QChar(context->arguments[i].toUInt16());
+    for (int i = 0; i < context->callData->argc; ++i) {
+        *ch = QChar(context->callData->args[i].toUInt16());
         ++ch;
     }
     return Value::fromString(context, str).asReturnedValue();
diff --git a/src/qml/jsruntime/qv4variantobject.cpp b/src/qml/jsruntime/qv4variantobject.cpp
index de72de2f07..720e4fa3a6 100644
--- a/src/qml/jsruntime/qv4variantobject.cpp
+++ b/src/qml/jsruntime/qv4variantobject.cpp
@@ -155,7 +155,8 @@ void VariantPrototype::init()
 
 QV4::ReturnedValue VariantPrototype::method_preserve(SimpleCallContext *ctx)
 {
-    VariantObject *o = ctx->thisObject.as<QV4::VariantObject>();
+    Scope scope(ctx);
+    Scoped<VariantObject> o(scope, ctx->callData->thisObject.as<QV4::VariantObject>());
     if (o && o->isScarce())
         o->node.remove();
     return Encode::undefined();
@@ -163,7 +164,8 @@ QV4::ReturnedValue VariantPrototype::method_preserve(SimpleCallContext *ctx)
 
 QV4::ReturnedValue VariantPrototype::method_destroy(SimpleCallContext *ctx)
 {
-    VariantObject *o = ctx->thisObject.as<QV4::VariantObject>();
+    Scope scope(ctx);
+    Scoped<VariantObject> o(scope, ctx->callData->thisObject.as<QV4::VariantObject>());
     if (o) {
         if (o->isScarce())
             o->node.remove();
@@ -174,7 +176,8 @@ QV4::ReturnedValue VariantPrototype::method_destroy(SimpleCallContext *ctx)
 
 QV4::ReturnedValue VariantPrototype::method_toString(SimpleCallContext *ctx)
 {
-    VariantObject *o = ctx->thisObject.as<QV4::VariantObject>();
+    Scope scope(ctx);
+    Scoped<VariantObject> o(scope, ctx->callData->thisObject.as<QV4::VariantObject>());
     if (!o)
         return Encode::undefined();
     QString result = o->data.toString();
@@ -185,7 +188,8 @@ QV4::ReturnedValue VariantPrototype::method_toString(SimpleCallContext *ctx)
 
 QV4::ReturnedValue VariantPrototype::method_valueOf(SimpleCallContext *ctx)
 {
-    VariantObject *o = ctx->thisObject.as<QV4::VariantObject>();
+    Scope scope(ctx);
+    Scoped<VariantObject> o(scope, ctx->callData->thisObject.as<QV4::VariantObject>());
     if (o) {
         QVariant v = o->data;
         switch (v.type()) {
@@ -204,7 +208,7 @@ QV4::ReturnedValue VariantPrototype::method_valueOf(SimpleCallContext *ctx)
             break;
         }
     }
-    return ctx->thisObject.asReturnedValue();
+    return ctx->callData->thisObject.asReturnedValue();
 }
 
 QT_END_NAMESPACE
diff --git a/src/qml/jsruntime/qv4vme_moth.cpp b/src/qml/jsruntime/qv4vme_moth.cpp
index 868158717c..ce2f76042f 100644
--- a/src/qml/jsruntime/qv4vme_moth.cpp
+++ b/src/qml/jsruntime/qv4vme_moth.cpp
@@ -170,9 +170,9 @@ static inline QV4::Value *getValueRef(QV4::ExecutionContext *context,
         QV4::CallContext *cc = static_cast<QV4::CallContext *>(c);
         const unsigned arg = param.index;
         Q_ASSERT(arg >= 0);
-        Q_ASSERT((unsigned) arg < cc->argumentCount);
-        Q_ASSERT(cc->arguments);
-        return cc->arguments + arg;
+        Q_ASSERT((unsigned) arg < cc->callData->argc);
+        Q_ASSERT(cc->callData->args);
+        return cc->callData->args + arg;
     } else if (param.isLocal()) {
         VMSTATS(paramIsLocal);
         const unsigned index = param.index;
@@ -546,7 +546,7 @@ QV4::ReturnedValue VME::run(QV4::ExecutionContext *context, const uchar *&code,
     MOTH_END_INSTR(Ret)
 
     MOTH_BEGIN_INSTR(LoadThis)
-        VALUE(instr.result) = context->thisObject;
+        VALUE(instr.result) = context->callData->thisObject;
     MOTH_END_INSTR(LoadThis)
 
     MOTH_BEGIN_INSTR(InplaceElementOp)