Changeset 37714 in webkit

Timestamp:

Oct 20, 2008 12:29:28 AM (16 years ago)

Author:

Darin Adler

Message:

2008-10-19 Darin Adler <Darin Adler>

Reviewed by Cameron Zwarich.

• finish ​https://bugs.webkit.org/show_bug.cgi?id=21732 improve performance by eliminating JSValue as a base class for JSCell

• VM/Machine.cpp: (JSC::Machine::cti_op_call_profiler): Use asFunction. (JSC::Machine::cti_vm_lazyLinkCall): Ditto. (JSC::Machine::cti_op_construct_JSConstructFast): Use asObject.

• kjs/JSCell.h: Re-sort friend classes. Eliminate inheritance from JSValue. Changed cast in asCell from static_cast to reinterpret_cast. Removed JSValue::getNumber(double&) and one of JSValue::getObject overloads.

• kjs/JSValue.h: Made the private constructor and destructor both non-virtual and also remove the definitions. This class can never be instantiated or derived.

Location:

trunk/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• VM/Machine.cpp (modified) (3 diffs)
• kjs/JSCell.h (modified) (4 diffs)
• kjs/JSValue.h (modified) (5 diffs)

trunk/JavaScriptCore/ChangeLog

@@ +1 @@
+2008-10-19  Darin Adler  <darin@apple.com>
+
+        Reviewed by Cameron Zwarich.
+
+        - finish https://bugs.webkit.org/show_bug.cgi?id=21732
+          improve performance by eliminating JSValue as a base class for JSCell
+
+        * VM/Machine.cpp:
+        (JSC::Machine::cti_op_call_profiler): Use asFunction.
+        (JSC::Machine::cti_vm_lazyLinkCall): Ditto.
+        (JSC::Machine::cti_op_construct_JSConstructFast): Use asObject.
+
+        * kjs/JSCell.h: Re-sort friend classes. Eliminate inheritance from
+        JSValue. Changed cast in asCell from static_cast to reinterpret_cast.
+        Removed JSValue::getNumber(double&) and one of JSValue::getObject
+        overloads.
+
+        * kjs/JSValue.h: Made the private constructor and destructor both
+        non-virtual and also remove the definitions. This class can never
+        be instantiated or derived.
+
 2008-10-19  Darin Adler  <darin@apple.com>
 

trunk/JavaScriptCore/VM/Machine.cpp

@@ -4617 +4617 @@
 
     ASSERT(*ARG_profilerReference);
-    (*ARG_profilerReference)->willExecute(ARG_callFrame, static_cast<JSFunction*>(ARG_src1));
+    (*ARG_profilerReference)->willExecute(ARG_callFrame, asFunction(ARG_src1));
 }
 
@@ -4677 +4677 @@
     CodeBlock* callerCodeBlock = callerCallFrame->codeBlock();
 
-    JSFunction* callee = static_cast<JSFunction*>(ARG_src1);
+    JSFunction* callee = asFunction(ARG_src1);
     CodeBlock* codeBlock = &callee->m_body->byteCode(callee->m_scopeChain.node());
     if (!codeBlock->ctiCode)
@@ -4842 +4842 @@
 #ifndef NDEBUG
     ConstructData constructData;
-    ASSERT(static_cast<JSFunction*>(ARG_src1)->getConstructData(constructData) == ConstructTypeJS);
+    ASSERT(asFunction(ARG_src1)->getConstructData(constructData) == ConstructTypeJS);
 #endif
 
     StructureID* structure;
     if (ARG_src2->isObject())
-        structure = static_cast<JSObject*>(ARG_src2)->inheritorID();
+        structure = asObject(ARG_src2)->inheritorID();
     else
-        structure = static_cast<JSFunction*>(ARG_src1)->m_scopeChain.node()->globalObject()->emptyObjectStructure();
+        structure = asFunction(ARG_src1)->m_scopeChain.node()->globalObject()->emptyObjectStructure();
     return new (ARG_globalData) JSObject(structure);
 }

trunk/JavaScriptCore/kjs/JSCell.h

@@ -30 +30 @@
 namespace JSC {
 
-    class JSCell : public JSValue {
+    class JSCell : Noncopyable {
+        friend class CTI;
+        friend class GetterSetter;
         friend class Heap;
-        friend class GetterSetter;
+        friend class JSNumberCell;
         friend class JSObject;
         friend class JSPropertyNameIterator;
+        friend class JSString;
         friend class JSValue;
-        friend class JSNumberCell;
-        friend class JSString;
         friend class Machine;
-        friend class CTI;
+
     private:
         explicit JSCell(StructureID*);
@@ -111 +112 @@
     {
         ASSERT(!JSImmediate::isImmediate(value));
-        return static_cast<JSCell*>(value.payload());
+        return reinterpret_cast<JSCell*>(value.payload());
     }
 
@@ -197 +198 @@
     }
 
-    inline bool JSValue::getNumber(double& v) const
-    {
-        if (JSImmediate::isImmediate(asValue())) {
-            v = JSImmediate::toDouble(asValue());
-            return true;
-        }
-        return asCell()->getNumber(v);
-    }
-
     inline double JSValue::getNumber() const
     {
@@ -221 +213 @@
     }
 
-    inline JSObject* JSValue::getObject()
-    {
-        return JSImmediate::isImmediate(asValue()) ? 0 : asCell()->getObject();
-    }
-
-    inline const JSObject* JSValue::getObject() const
+    inline JSObject* JSValue::getObject() const
     {
         return JSImmediate::isImmediate(asValue()) ? 0 : asCell()->getObject();

trunk/JavaScriptCore/kjs/JSValue.h

@@ -36 +36 @@
 namespace JSC {
 
-    class ExecState;
     class Identifier;
-    class JSCell;
-    class JSObject;
     class JSString;
     class PropertySlot;
     class PutPropertySlot;
-    class StructureID;
 
     struct ClassInfo;
@@ -50 +46 @@
     enum PreferredPrimitiveType { NoPreference, PreferNumber, PreferString };
 
-    /**
-     * JSValue is the base type for all primitives (Undefined, Null, Boolean,
-     * String, Number) and objects in ECMAScript.
-     *
-     * Note: you should never inherit from JSValue as it is for primitive types
-     * only (all of which are provided internally by KJS). Instead, inherit from
-     * JSObject.
-     */
     class JSValue : Noncopyable {
-        friend class JSCell; // so it can derive from this class
     private:
         JSValue();
-        virtual ~JSValue();
+        ~JSValue();
 
     public:
@@ -74 +61 @@
         bool isGetterSetter() const;
         bool isObject() const;
-        bool isObject(const ClassInfo*) const; // FIXME: Merge with inherits.
+        bool isObject(const ClassInfo*) const;
         
         // Extracting the value.
         bool getBoolean(bool&) const;
         bool getBoolean() const; // false if not a boolean
-        bool getNumber(double&) const;
         double getNumber() const; // NaN if not a number
         double uncheckedGetNumber() const;
         bool getString(UString&) const;
         UString getString() const; // null string if not a string
-        JSObject* getObject(); // NULL if not an object
-        const JSObject* getObject() const; // NULL if not an object
+        JSObject* getObject() const; // 0 if not an object
 
         CallType getCallData(CallData&);
@@ -105 +90 @@
         double toNumber(ExecState*) const;
         JSValuePtr toJSNumber(ExecState*) const; // Fast path for when you expect that the value is an immediate number.
+
         UString toString(ExecState*) const;
         JSObject* toObject(ExecState*) const;
@@ -160 +146 @@
     uint32_t toUInt32SlowCase(double, bool& ok);
 
-    inline JSValue::JSValue()
-    {
-    }
-
-    inline JSValue::~JSValue()
-    {
-    }
-
     inline JSValuePtr JSValue::asValue() const
     {