Get rid of Value::asArrayIndex()

It was only used in a few places now, that can be replaced by
either using a PropertyKey, or by limiting the fast path
optimization in the runtime to array indices smaller than
INT_MAX. Since there are less branches this should even be
faster for pretty much all use cases.

Change-Id: Ib4f2f2f3e27f14ad180b810546e82ac83170b106
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

3 files changed, 11 insertions, 43 deletions

diff --git a/src/qml/jsruntime/qv4engine.cpp b/src/qml/jsruntime/qv4engine.cpp
index b42633b446..e3a99e9ddb 100644
--- a/src/qml/jsruntime/qv4engine.cpp
+++ b/src/qml/jsruntime/qv4engine.cpp
@@ -1398,9 +1398,6 @@ static QV4::ReturnedValue objectFromVariantMap(QV4::ExecutionEngine *e, const QV
     QV4::ScopedValue v(scope);
     for (QVariantMap::const_iterator iter = map.begin(), cend = map.end(); iter != cend; ++iter) {
         s = e->newString(iter.key());
-        uint idx = s->asArrayIndex();
-        if (idx > 16 && (!o->arrayData() || idx > o->arrayData()->length() * 2))
-            o->initSparseArray();
         o->put(s, (v = e->fromVariant(iter.value())));
     }
     return o.asReturnedValue();
@@ -1572,11 +1569,13 @@ static QV4::ReturnedValue variantMapToJS(QV4::ExecutionEngine *v4, const QVarian
     QV4::Scope scope(v4);
     QV4::ScopedObject o(scope, v4->newObject());
     QV4::ScopedString s(scope);
+    QV4::ScopedPropertyKey key(scope);
     QV4::ScopedValue v(scope);
     for (QVariantMap::const_iterator it = vmap.constBegin(), cend = vmap.constEnd(); it != cend; ++it) {
         s = v4->newIdentifier(it.key());
+        key = s->propertyKey();
         v = variantToJS(v4, it.value());
-        uint idx = s->asArrayIndex();
+        uint idx = key->asArrayIndex();
         if (idx < UINT_MAX)
             o->arraySet(idx, v);
         else
diff --git a/src/qml/jsruntime/qv4runtime.cpp b/src/qml/jsruntime/qv4runtime.cpp
index 8a6b011aa2..0f3bd66ba4 100644
--- a/src/qml/jsruntime/qv4runtime.cpp
+++ b/src/qml/jsruntime/qv4runtime.cpp
@@ -619,7 +619,8 @@ static Q_NEVER_INLINE ReturnedValue getElementIntFallback(ExecutionEngine *engin
 
 static Q_NEVER_INLINE ReturnedValue getElementFallback(ExecutionEngine *engine, const Value &object, const Value &index)
 {
-    Q_ASSERT(index.asArrayIndex() == UINT_MAX);
+    Q_ASSERT(!index.isPositiveInt());
+
     Scope scope(engine);
 
     ScopedObject o(scope, object);
@@ -641,8 +642,8 @@ static Q_NEVER_INLINE ReturnedValue getElementFallback(ExecutionEngine *engine,
 
 ReturnedValue Runtime::method_loadElement(ExecutionEngine *engine, const Value &object, const Value &index)
 {
-    uint idx = 0;
-    if (index.asArrayIndex(idx)) {
+    if (index.isPositiveInt()) {
+        uint idx = static_cast<uint>(index.int_32());
         if (Heap::Base *b = object.heapObject()) {
             if (b->internalClass->vtable->isObject) {
                 Heap::Object *o = static_cast<Heap::Object *>(b);
@@ -667,8 +668,8 @@ static Q_NEVER_INLINE bool setElementFallback(ExecutionEngine *engine, const Val
     if (engine->hasException)
         return false;
 
-    uint idx = 0;
-    if (index.asArrayIndex(idx)) {
+    if (index.isPositiveInt()) {
+        uint idx = static_cast<uint>(index.int_32());
         if (o->d()->arrayData && o->d()->arrayData->type == Heap::ArrayData::Simple) {
             Heap::SimpleArrayData *s = o->d()->arrayData.cast<Heap::SimpleArrayData>();
             if (idx < s->values.size) {
@@ -687,8 +688,8 @@ static Q_NEVER_INLINE bool setElementFallback(ExecutionEngine *engine, const Val
 
 void Runtime::method_storeElement(ExecutionEngine *engine, const Value &object, const Value &index, const Value &value)
 {
-    uint idx = 0;
-    if (index.asArrayIndex(idx)) {
+    if (index.isPositiveInt()) {
+        uint idx = static_cast<uint>(index.int_32());
         if (Heap::Base *b = object.heapObject()) {
             if (b->internalClass->vtable->isObject) {
                 Heap::Object *o = static_cast<Heap::Object *>(b);
diff --git a/src/qml/jsruntime/qv4value_p.h b/src/qml/jsruntime/qv4value_p.h
index ac0a52f7a8..7c9ca9c0bf 100644
--- a/src/qml/jsruntime/qv4value_p.h
+++ b/src/qml/jsruntime/qv4value_p.h
@@ -465,8 +465,6 @@ public:
         return static_cast<const T *>(managed());
     }
 
-    inline uint asArrayIndex() const;
-    inline bool asArrayIndex(uint &idx) const;
 #ifndef V4_BOOTSTRAP
     uint asArrayLength(bool *ok) const;
 #endif
@@ -553,36 +551,6 @@ inline double Value::toNumber() const
     return toNumberImpl();
 }
 
-
-#ifndef V4_BOOTSTRAP
-inline uint Value::asArrayIndex() const
-{
-    if (Q_LIKELY(isPositiveInt())) {
-        return (uint)int_32();
-    }
-    if (Q_UNLIKELY(!isDouble()))
-        return UINT_MAX;
-    double d = doubleValue();
-    uint idx = (uint)d;
-    if (idx == d)
-        return idx;
-    return UINT_MAX;
-}
-
-inline bool Value::asArrayIndex(uint &idx) const
-{
-    if (Q_LIKELY(isPositiveInt())) {
-        idx = (uint)int_32();
-        return true;
-    }
-    if (Q_UNLIKELY(!isDouble()))
-        return false;
-    double d = doubleValue();
-    idx = (uint)d;
-    return (idx == d && idx != UINT_MAX);
-}
-#endif
-
 inline
 ReturnedValue Heap::Base::asReturnedValue() const
 {