Changeset 35446 in webkit for trunk/JavaScriptCore/kjs/nodes.cpp

Timestamp:

Jul 30, 2008, 7:42:03 AM (17 years ago)

Author:

[email protected]

Message:

2008-07-29 Gavin Barraclough <​[email protected]>

Reviewed by Geoff Garen.

Bug 20209: Atomize constant strings
<​https://bugs.webkit.org/show_bug.cgi?id=20209>

Prevents significant performance degradation seen when a script contains multiple
identical strings that are used as keys to identify properties on objects.

No performance change on SunSpider.

• kjs/nodes.cpp: Atomize constant strings.

File:

• trunk/JavaScriptCore/kjs/nodes.cpp (modified) (1 diff)

trunk/JavaScriptCore/kjs/nodes.cpp

@@ -253 +253 @@
     if (dst == ignoredResult())
         return 0;
-    // FIXME: should we try to atomize constant strings?
-    return generator.emitLoad(generator.finalDestination(dst), jsOwnedString(generator.globalExec(), m_value));
+
+    // We atomize constant strings, in case they're later used in property lookup.
+    return generator.emitLoad(generator.finalDestination(dst), jsOwnedString(generator.globalExec(), Identifier(generator.globalExec(), m_value).ustring()));
 }