Changeset 34964 in webkit for trunk/JavaScriptCore/kjs/JSString.h

Timestamp:

Jul 2, 2008, 5:47:00 PM (17 years ago)

Author:

[email protected]

Message:

2008-07-02 Geoffrey Garen <​[email protected]>

Reviewed by Oliver Hunt.

Optimized a[n] get for cases where a is an array or a string, and a[n]
put for cases where a is an array.

SunSpider says 9.0% faster.

File:

• trunk/JavaScriptCore/kjs/JSString.h (modified) (1 diff)

trunk/JavaScriptCore/kjs/JSString.h

@@ -43 +43 @@
     bool getStringPropertySlot(ExecState*, const Identifier& propertyName, PropertySlot&);
     bool getStringPropertySlot(unsigned propertyName, PropertySlot&);
+
+    bool canGetIndex(unsigned i) { return i < static_cast<unsigned>(m_value.size()); }
+    JSValue* getIndex(ExecState* exec, unsigned i)
+    {
+        ASSERT(canGetIndex(i));
+        return new (exec) JSString(m_value.substr(i, 1));
+    }
 
   private: