Avoid creating array attributes if possible

Holes in arrays should be represented by an empty
value, not by creating/setting array attributes.

Reason is that the creation is irreversable, and slows
down execution. This speeds up crypto.js by 10%

Change-Id: I2e5472575479a5f2dbe53f59ecb8ed3aeab1be7a
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

1 files changed, 5 insertions, 6 deletions

diff --git a/src/qml/jsruntime/qv4argumentsobject.cpp b/src/qml/jsruntime/qv4argumentsobject.cpp
index c815036550..47b149c9d5 100644
--- a/src/qml/jsruntime/qv4argumentsobject.cpp
+++ b/src/qml/jsruntime/qv4argumentsobject.cpp
@@ -127,12 +127,11 @@ bool ArgumentsObject::defineOwnProperty(ExecutionContext *ctx, uint index, const
     isNonStrictArgumentsObject = true;
 
     if (isMapped && attrs.isData()) {
-        if (!attrs.isGeneric()) {
-            ScopedCallData callData(scope, 1);
-            callData->thisObject = this->asReturnedValue();
-            callData->args[0] = desc.value;
-            map.setter()->call(callData);
-        }
+        ScopedCallData callData(scope, 1);
+        callData->thisObject = this->asReturnedValue();
+        callData->args[0] = desc.value;
+        map.setter()->call(callData);
+
         if (attrs.isWritable()) {
             *pd = map;
             arrayAttributes[pidx] = mapAttrs;