Changeset 25955 in webkit

Timestamp:

Oct 2, 2007 8:42:46 PM (17 years ago)

Author:

mjs

Message:

Reviewed by Oliver.

• skip extra hash lookup and avoid converting char* to UString for 19% speedup on CK JS array test ​http://bugs.webkit.org/show_bug.cgi?id=15350

• kjs/array_object.cpp: (ArrayProtoFunc::callAsFunction): Implement the two mentioned optimizations.

Location:

branches/feature-branch/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• kjs/array_object.cpp (modified) (1 diff)

branches/feature-branch/JavaScriptCore/ChangeLog

@@ +1 @@
+2007-10-02  Maciej Stachowiak  <mjs@apple.com>
+
+        Reviewed by Oliver.
+        
+        - skip extra hash lookup and avoid converting char* to UString for 19% speedup on CK JS array test 
+        http://bugs.webkit.org/show_bug.cgi?id=15350
+
+        * kjs/array_object.cpp:
+        (ArrayProtoFunc::callAsFunction): Implement the two mentioned optimizations.
+
 2007-10-02  Maciej Stachowiak  <mjs@apple.com>
 

branches/feature-branch/JavaScriptCore/kjs/array_object.cpp

@@ -536 +536 @@
   case Join: {
     static HashSet<JSObject*> visitedElems;
-    if (visitedElems.contains(thisObj))
-        return jsString("");
-    UString separator = ",";
-    UString str = "";
-
-    visitedElems.add(thisObj);
+    static const UString empty("");
+    static const UString comma(",");
+    bool alreadyVisited = !visitedElems.add(thisObj).second;
+    if (alreadyVisited)
+        return jsString(empty);
+    UString separator = comma;
+    UString str = empty;
+
     if (id == Join && !args[0]->isUndefined())
         separator = args[0]->toString(exec);