Determine whether or not an object literal requires a sparse array at compile time

Change-Id: Ieb7f6ee97a4f251f1e2369850ebb9e2931f84ac1
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

3 files changed, 11 insertions, 8 deletions

diff --git a/src/qml/jsruntime/qv4runtime.cpp b/src/qml/jsruntime/qv4runtime.cpp
index 7c7ce23bcb..a3ba4b0d75 100644
--- a/src/qml/jsruntime/qv4runtime.cpp
+++ b/src/qml/jsruntime/qv4runtime.cpp
@@ -1100,12 +1100,18 @@ ReturnedValue __qmljs_builtin_define_array(ExecutionContext *ctx, Value *values,
     return a.asReturnedValue();
 }
 
-ReturnedValue __qmljs_builtin_define_object_literal(QV4::ExecutionContext *ctx, const QV4::Value *args, int classId, int arrayValueCount, int arrayGetterSetterCount)
+ReturnedValue __qmljs_builtin_define_object_literal(QV4::ExecutionContext *ctx, const QV4::Value *args, int classId, int arrayValueCount, int arrayGetterSetterCountAndFlags)
 {
     Scope scope(ctx);
     QV4::InternalClass *klass = ctx->compilationUnit->runtimeClasses[classId];
     Scoped<Object> o(scope, ctx->engine->newObject(klass));
 
+    {
+        bool needSparseArray = arrayGetterSetterCountAndFlags >> 30;
+        if (needSparseArray)
+            o->initSparseArray();
+    }
+
     for (uint i = 0; i < klass->size; ++i) {
         if (klass->propertyData[i].isData())
             o->memberData[i].value = *args++;
@@ -1120,18 +1126,15 @@ ReturnedValue __qmljs_builtin_define_object_literal(QV4::ExecutionContext *ctx,
     ScopedValue entry(scope);
     for (int i = 0; i < arrayValueCount; ++i) {
         uint idx = args->toUInt32();
-        if (idx > 16 && (!o->arrayData || idx > o->arrayData->length() * 2))
-            o->initSparseArray();
         ++args;
         entry = *args++;
         o->arraySet(idx, entry);
     }
 
     ScopedProperty pd(scope);
-    for (int i = 0; i < arrayGetterSetterCount; ++i) {
+    uint arrayGetterSetterCount = arrayGetterSetterCountAndFlags & ((1 << 30) - 1);
+    for (uint i = 0; i < arrayGetterSetterCount; ++i) {
         uint idx = args->toUInt32();
-        if (idx > 16 && (!o->arrayData || idx > o->arrayData->length() * 2))
-            o->initSparseArray();
         ++args;
         pd->value = *args;
         ++args;
diff --git a/src/qml/jsruntime/qv4runtime_p.h b/src/qml/jsruntime/qv4runtime_p.h
index dbe7e030e1..dbdb891328 100644
--- a/src/qml/jsruntime/qv4runtime_p.h
+++ b/src/qml/jsruntime/qv4runtime_p.h
@@ -142,7 +142,7 @@ QV4::ExecutionContext *__qmljs_builtin_pop_scope(QV4::ExecutionContext *ctx);
 ReturnedValue __qmljs_builtin_unwind_exception(ExecutionContext *ctx);
 void __qmljs_builtin_declare_var(QV4::ExecutionContext *ctx, bool deletable, const QV4::StringRef name);
 QV4::ReturnedValue __qmljs_builtin_define_array(QV4::ExecutionContext *ctx, Value *values, uint length);
-QV4::ReturnedValue __qmljs_builtin_define_object_literal(QV4::ExecutionContext *ctx, const QV4::Value *args, int classId, int arrayValueCount, int arrayGetterSetterCount);
+QV4::ReturnedValue __qmljs_builtin_define_object_literal(QV4::ExecutionContext *ctx, const QV4::Value *args, int classId, int arrayValueCount, int arrayGetterSetterCountAndFlags);
 QV4::ReturnedValue __qmljs_builtin_setup_arguments_object(ExecutionContext *ctx);
 void __qmljs_builtin_convert_this_to_object(ExecutionContext *ctx);
 
diff --git a/src/qml/jsruntime/qv4vme_moth.cpp b/src/qml/jsruntime/qv4vme_moth.cpp
index 5ae0b3daff..a657b34be5 100644
--- a/src/qml/jsruntime/qv4vme_moth.cpp
+++ b/src/qml/jsruntime/qv4vme_moth.cpp
@@ -481,7 +481,7 @@ QV4::ReturnedValue VME::run(QV4::ExecutionContext *context, const uchar *code
 
     MOTH_BEGIN_INSTR(CallBuiltinDefineObjectLiteral)
         QV4::Value *args = stack + instr.args;
-    STOREVALUE(instr.result, __qmljs_builtin_define_object_literal(context, args, instr.internalClassId, instr.arrayValueCount, instr.arrayGetterSetterCount));
+    STOREVALUE(instr.result, __qmljs_builtin_define_object_literal(context, args, instr.internalClassId, instr.arrayValueCount, instr.arrayGetterSetterCountAndFlags));
     MOTH_END_INSTR(CallBuiltinDefineObjectLiteral)
 
     MOTH_BEGIN_INSTR(CallBuiltinSetupArgumentsObject)