Changeset 43220 in webkit for trunk/JavaScriptCore/runtime/JSFunction.cpp

Timestamp:

May 5, 2009, 4:34:23 AM (16 years ago)

Author:

[email protected]

Message:

Bug 25559: Improve native function call performance
<​https://bugs.webkit.org/show_bug.cgi?id=25559>

Reviewed by Gavin Barraclough

In order to cache calls to native functions we now make the standard
prototype functions use a small assembly thunk that converts the JS
calling convention into the native calling convention. As this is
only beneficial in the JIT we use the NativeFunctionWrapper typedef
to alternate between PrototypeFunction and JSFunction to keep the
code sane. This change from PrototypeFunction to NativeFunctionWrapper
is the bulk of this patch.

File:

• trunk/JavaScriptCore/runtime/JSFunction.cpp (modified) (13 diffs)

trunk/JavaScriptCore/runtime/JSFunction.cpp

@@ -46 +46 @@
 const ClassInfo JSFunction::info = { "Function", &InternalFunction::info, 0, 0 };
 
+JSFunction::JSFunction(ExecState* exec, PassRefPtr<Structure> structure, int length, const Identifier& name, NativeFunction func)
+    : Base(&exec->globalData(), structure, name)
+#if ENABLE(JIT)
+    , m_body(exec->globalData().nativeFunctionThunk())
+#else
+    , m_body(0)
+#endif
+{
+#if ENABLE(JIT)
+    setNativeFunction(func);
+    putDirect(exec->propertyNames().length, jsNumber(exec, length), DontDelete | ReadOnly | DontEnum);
+#else
+    UNUSED_PARAM(length);
+    UNUSED_PARAM(func);
+    ASSERT_NOT_REACHED();
+#endif
+}
+
 JSFunction::JSFunction(ExecState* exec, const Identifier& name, FunctionBodyNode* body, ScopeChainNode* scopeChainNode)
     : Base(&exec->globalData(), exec->lexicalGlobalObject()->functionStructure(), name)
     , m_body(body)
-    , m_scopeChain(scopeChainNode)
-{
+{
+    setScopeChain(scopeChainNode);
 }
 
@@ -59 +77 @@
     // are based on a check for the this pointer value for this JSFunction - which will no longer be valid once
     // this memory is freed and may be reused (potentially for another, different JSFunction).
-    if (m_body && m_body->isGenerated())
-        m_body->generatedBytecode().unlinkCallers();
+    if (!isHostFunction()) {
+        if (m_body && m_body->isGenerated())
+            m_body->generatedBytecode().unlinkCallers();
+        scopeChain().~ScopeChain();
+    }
+    
 #endif
 }
@@ -67 +89 @@
 {
     Base::mark();
-    m_body->mark();
-    m_scopeChain.mark();
+    if (!isHostFunction()) {
+        m_body->mark();
+        scopeChain().mark();
+    }
 }
 
 CallType JSFunction::getCallData(CallData& callData)
 {
+    if (isHostFunction()) {
+        callData.native.function = nativeFunction();
+        return CallTypeHost;
+    }
     callData.js.functionBody = m_body.get();
-    callData.js.scopeChain = m_scopeChain.node();
+    callData.js.scopeChain = scopeChain().node();
     return CallTypeJS;
 }
@@ -80 +108 @@
 JSValue JSFunction::call(ExecState* exec, JSValue thisValue, const ArgList& args)
 {
-    return exec->interpreter()->execute(m_body.get(), exec, this, thisValue.toThisObject(exec), args, m_scopeChain.node(), exec->exceptionSlot());
+    ASSERT(!isHostFunction());
+    return exec->interpreter()->execute(m_body.get(), exec, this, thisValue.toThisObject(exec), args, scopeChain().node(), exec->exceptionSlot());
 }
 
@@ -86 +115 @@
 {
     JSFunction* thisObj = asFunction(slot.slotBase());
+    ASSERT(!thisObj->isHostFunction());
     return exec->interpreter()->retrieveArguments(exec, thisObj);
 }
@@ -92 +122 @@
 {
     JSFunction* thisObj = asFunction(slot.slotBase());
+    ASSERT(!thisObj->isHostFunction());
     return exec->interpreter()->retrieveCaller(exec, thisObj);
 }
@@ -98 +129 @@
 {
     JSFunction* thisObj = asFunction(slot.slotBase());
+    ASSERT(!thisObj->isHostFunction());
     return jsNumber(exec, thisObj->m_body->parameterCount());
 }
@@ -103 +135 @@
 bool JSFunction::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
 {
+    if (isHostFunction())
+        return Base::getOwnPropertySlot(exec, propertyName, slot);
+
     if (propertyName == exec->propertyNames().prototype) {
         JSValue* location = getDirectLocation(propertyName);
 
         if (!location) {
-            JSObject* prototype = new (exec) JSObject(m_scopeChain.globalObject()->emptyObjectStructure());
+            JSObject* prototype = new (exec) JSObject(scopeChain().globalObject()->emptyObjectStructure());
             prototype->putDirect(exec->propertyNames().constructor, this, DontEnum);
             putDirect(exec->propertyNames().prototype, prototype, DontDelete);
@@ -136 +171 @@
 void JSFunction::put(ExecState* exec, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)
 {
+    if (isHostFunction()) {
+        Base::put(exec, propertyName, value, slot);
+        return;
+    }
     if (propertyName == exec->propertyNames().arguments || propertyName == exec->propertyNames().length)
         return;
@@ -143 +182 @@
 bool JSFunction::deleteProperty(ExecState* exec, const Identifier& propertyName)
 {
+    if (isHostFunction())
+        return Base::deleteProperty(exec, propertyName);
     if (propertyName == exec->propertyNames().arguments || propertyName == exec->propertyNames().length)
         return false;
@@ -151 +192 @@
 ConstructType JSFunction::getConstructData(ConstructData& constructData)
 {
+    if (isHostFunction())
+        return ConstructTypeNone;
     constructData.js.functionBody = m_body.get();
-    constructData.js.scopeChain = m_scopeChain.node();
+    constructData.js.scopeChain = scopeChain().node();
     return ConstructTypeJS;
 }
@@ -158 +201 @@
 JSObject* JSFunction::construct(ExecState* exec, const ArgList& args)
 {
+    ASSERT(!isHostFunction());
     Structure* structure;
     JSValue prototype = get(exec, exec->propertyNames().prototype);
@@ -166 +210 @@
     JSObject* thisObj = new (exec) JSObject(structure);
 
-    JSValue result = exec->interpreter()->execute(m_body.get(), exec, this, thisObj, args, m_scopeChain.node(), exec->exceptionSlot());
+    JSValue result = exec->interpreter()->execute(m_body.get(), exec, this, thisObj, args, scopeChain().node(), exec->exceptionSlot());
     if (exec->hadException() || !result.isObject())
         return thisObj;