Changeset 35806 in webkit for trunk/JavaScriptCore/kjs/JSArray.cpp

Timestamp:

Aug 17, 2008, 12:57:39 AM (17 years ago)

Author:

[email protected]

Message:

2007-08-16 Geoffrey Garen <​[email protected]>

Reviewed by Oliver Hunt.

Sped up property access for array.length and string.length by adding a
mechanism for returning a temporary value directly instead of returning
a pointer to a function that retrieves the value.

Also removed some unused cruft from PropertySlot.

SunSpider says 0.5% - 1.2% faster.

NOTE: This optimization is not a good idea in general, because it's
actually a pessimization in the case of resolve for assignment,
and it may get in the way of other optimizations in the future.

File:

• trunk/JavaScriptCore/kjs/JSArray.cpp (modified) (2 diffs)

trunk/JavaScriptCore/kjs/JSArray.cpp

@@ -174 +174 @@
 }
 
-JSValue* JSArray::lengthGetter(ExecState* exec, const Identifier&, const PropertySlot& slot)
-{
-    return jsNumber(exec, static_cast<JSArray*>(slot.slotBase())->m_length);
-}
-
 bool JSArray::getOwnPropertySlot(ExecState* exec, unsigned i, PropertySlot& slot)
 {
@@ -211 +206 @@
 {
     if (propertyName == exec->propertyNames().length) {
-        slot.setCustom(this, lengthGetter);
+        slot.setValue(jsNumber(exec, getLength()));
         return true;
     }