Changeset 31226 in webkit

Timestamp:

Mar 21, 2008, 9:59:20 PM (17 years ago)

Author:

oliver@apple.com

Message:

Optimise lookup of Math, undefined, NaN and Infinity

Reviewed by Maciej

Added a method to JSVariableObject to allow us to inject DontDelete properties
into the symbol table and localStorage. This results in a 0.4% progression in
SunSpider, with a 8% gain in math-partial-sums.

Location:

trunk/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• kjs/JSGlobalObject.cpp (modified) (1 diff)
• kjs/JSVariableObject.h (modified) (2 diffs)

trunk/JavaScriptCore/ChangeLog

@@ +1 @@
+2008-03-21  Oliver Hunt  <oliver@apple.com>
+
+        Reviewed by Maciej.
+
+        Optimise lookup of Math, undefined, NaN and Infinity
+
+        Added a method to JSVariableObject to allow us to inject DontDelete properties
+        into the symbol table and localStorage.  This results in a 0.4% progression in
+        SunSpider, with a 8% gain in math-partial-sums.
+
+        * kjs/JSGlobalObject.cpp:
+        (KJS::JSGlobalObject::reset):
+        * kjs/JSVariableObject.h:
+        (KJS::JSVariableObject::symbolTableInsert):
+
 2008-03-21  Oliver Hunt  <oliver@apple.com>
 

trunk/JavaScriptCore/kjs/JSGlobalObject.cpp

@@ -310 +310 @@
 
     // Set global values.
-
-    putDirect("Math", new MathObjectImp(exec, d()->objectPrototype), DontEnum);
-
-    putDirect("NaN", jsNaN(), DontEnum | DontDelete);
-    putDirect("Infinity", jsNumber(Inf), DontEnum | DontDelete);
-    putDirect("undefined", jsUndefined(), DontEnum | DontDelete);
+    Identifier mathIdent = "Math";
+    JSValue* mathObject = new MathObjectImp(exec, d()->objectPrototype);
+    symbolTableInsert(mathIdent, mathObject, DontEnum | DontDelete);
+    
+    Identifier nanIdent = "NaN";
+    JSValue* nanValue = jsNaN();
+    symbolTableInsert(nanIdent, nanValue, DontEnum | DontDelete);
+    
+    Identifier infinityIdent = "Infinity";
+    JSValue* infinityValue = jsNumber(Inf);
+    symbolTableInsert(infinityIdent, infinityValue, DontEnum | DontDelete);
+    
+    Identifier undefinedIdent = "undefined";
+    JSValue* undefinedValue = jsUndefined();
+    symbolTableInsert(undefinedIdent, undefinedValue, DontEnum | DontDelete);
 
     // Set global functions.

trunk/JavaScriptCore/kjs/JSVariableObject.h

@@ -87 +87 @@
         bool symbolTablePut(const Identifier&, JSValue*);
         bool symbolTableInitializeVariable(const Identifier&, JSValue*, unsigned attributes);
+        bool symbolTableInsert(const Identifier&, JSValue*, unsigned attributes);
 
         JSVariableObjectData* d;
@@ -135 +136 @@
         return true;
     }
+    
+    inline bool JSVariableObject::symbolTableInsert(const Identifier& propertyName, JSValue* value, unsigned attributes)
+    {
+        if (symbolTable().get(propertyName.ustring().rep()) != missingSymbolMarker())
+            return false;
 
+        ASSERT((attributes & DontDelete) != 0);
+        size_t localStorageIndex = d->localStorage.size();
+        d->localStorage.append(LocalStorageEntry(value, attributes));
+        symbolTable().add(propertyName.ustring().rep(), localStorageIndex);
+        return true;
+    }
 } // namespace KJS