Speedup JS instanceof operator

Cache the prototype of the functionobject, and inline hasInstance.
This removes a vtbl method and speeds things up quite a bit.

Change-Id: Ic68f301f7e09763d445a98bffa2cd201303f902e
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

7 files changed, 50 insertions, 58 deletions

diff --git a/src/qml/jsruntime/qv4context.cpp b/src/qml/jsruntime/qv4context.cpp
index 372c9ce54b..b0fb535361 100644
--- a/src/qml/jsruntime/qv4context.cpp
+++ b/src/qml/jsruntime/qv4context.cpp
@@ -58,7 +58,6 @@ const ManagedVTable ExecutionContext::static_vtbl =
     markObjects,
     destroy,
     0 /*collectDeletables*/,
-    hasInstance,
     0,
     0,
     0,
diff --git a/src/qml/jsruntime/qv4functionobject.cpp b/src/qml/jsruntime/qv4functionobject.cpp
index 037f06cd35..32ef98327b 100644
--- a/src/qml/jsruntime/qv4functionobject.cpp
+++ b/src/qml/jsruntime/qv4functionobject.cpp
@@ -81,6 +81,8 @@ FunctionObject::FunctionObject(ExecutionContext *scope, const StringRef name, bo
     , formalParameterCount(0)
     , varCount(0)
     , function(0)
+    , protoCacheClass(0)
+    , protoCacheIndex(UINT_MAX)
 {
      init(name, createProto);
 }
@@ -93,6 +95,8 @@ FunctionObject::FunctionObject(ExecutionContext *scope, const QString &name, boo
     , formalParameterCount(0)
     , varCount(0)
     , function(0)
+    , protoCacheClass(0)
+    , protoCacheIndex(UINT_MAX)
 {
     // set the name to something here, so that a gc run a few lines below doesn't crash on it
     this->name = scope->engine->id_undefined;
@@ -158,33 +162,6 @@ ReturnedValue FunctionObject::newInstance()
     return construct(callData);
 }
 
-bool FunctionObject::hasInstance(Managed *that, const ValueRef value)
-{
-    Scope scope(that->internalClass->engine);
-    ScopedFunctionObject f(scope, static_cast<FunctionObject *>(that));
-
-    ScopedObject v(scope, value);
-    if (!v)
-        return false;
-
-    Scoped<Object> o(scope, f->get(scope.engine->id_prototype));
-    if (!o) {
-        scope.engine->current->throwTypeError();
-        return false;
-    }
-
-    while (v) {
-        v = v->prototype();
-
-        if (! v)
-            break;
-        else if (o.getPointer() == v)
-            return true;
-    }
-
-    return false;
-}
-
 ReturnedValue FunctionObject::construct(Managed *that, CallData *)
 {
     ExecutionEngine *v4 = that->internalClass->engine;
@@ -231,6 +208,19 @@ FunctionObject *FunctionObject::creatScriptFunction(ExecutionContext *scope, Fun
     return new (scope->engine->memoryManager) SimpleScriptFunction(scope, function);
 }
 
+ReturnedValue FunctionObject::protoProperty()
+{
+    if (protoCacheClass != internalClass) {
+        protoCacheClass = internalClass;
+        protoCacheIndex = internalClass->find(internalClass->engine->id_prototype);
+    }
+    if (protoCacheIndex < UINT_MAX) {
+        if (internalClass->propertyData.at(protoCacheIndex).isData())
+            return memberData[protoCacheIndex].value.asReturnedValue();
+    }
+    return get(internalClass->engine->id_prototype);
+}
+
 
 DEFINE_MANAGED_VTABLE(FunctionCtor);
 
@@ -667,6 +657,7 @@ BoundFunction::BoundFunction(ExecutionContext *scope, FunctionObjectRef target,
     , boundArgs(boundArgs)
 {
     vtbl = &static_vtbl;
+    subtype = FunctionObject::BoundFunction;
     this->boundThis = boundThis;
 
     Scope s(scope);
@@ -718,12 +709,6 @@ ReturnedValue BoundFunction::construct(Managed *that, CallData *dd)
     return f->target->construct(callData);
 }
 
-bool BoundFunction::hasInstance(Managed *that, const ValueRef value)
-{
-    BoundFunction *f = static_cast<BoundFunction *>(that);
-    return FunctionObject::hasInstance(f->target, value);
-}
-
 void BoundFunction::markObjects(Managed *that, ExecutionEngine *e)
 {
     BoundFunction *o = static_cast<BoundFunction *>(that);
diff --git a/src/qml/jsruntime/qv4functionobject_p.h b/src/qml/jsruntime/qv4functionobject_p.h
index 2fc36d862f..c4fd49bec5 100644
--- a/src/qml/jsruntime/qv4functionobject_p.h
+++ b/src/qml/jsruntime/qv4functionobject_p.h
@@ -97,7 +97,8 @@ struct Q_QML_EXPORT FunctionObject: Object {
     // Used with Managed::subType
     enum FunctionType {
         RegularFunction = 0,
-        WrappedQtMethod = 1
+        WrappedQtMethod = 1,
+        BoundFunction
     };
 
     enum {
@@ -112,6 +113,8 @@ struct Q_QML_EXPORT FunctionObject: Object {
     unsigned int formalParameterCount;
     unsigned int varCount;
     Function *function;
+    InternalClass *protoCacheClass;
+    uint protoCacheIndex;
 
     FunctionObject(ExecutionContext *scope, const StringRef name, bool createProto = false);
     FunctionObject(ExecutionContext *scope, const QString &name = QString(), bool createProto = false);
@@ -136,11 +139,12 @@ struct Q_QML_EXPORT FunctionObject: Object {
 
     static FunctionObject *creatScriptFunction(ExecutionContext *scope, Function *function);
 
+    ReturnedValue protoProperty();
+
 protected:
     FunctionObject(InternalClass *ic);
 
     static void markObjects(Managed *that, ExecutionEngine *e);
-    static bool hasInstance(Managed *that, const ValueRef value);
     static void destroy(Managed *that)
     { static_cast<FunctionObject*>(that)->~FunctionObject(); }
 };
@@ -235,7 +239,6 @@ struct BoundFunction: FunctionObject {
 
     static void destroy(Managed *);
     static void markObjects(Managed *that, ExecutionEngine *e);
-    static bool hasInstance(Managed *that, const ValueRef value);
 };
 
 }
diff --git a/src/qml/jsruntime/qv4managed.cpp b/src/qml/jsruntime/qv4managed.cpp
index 6455a08037..895ae8d91b 100644
--- a/src/qml/jsruntime/qv4managed.cpp
+++ b/src/qml/jsruntime/qv4managed.cpp
@@ -52,7 +52,6 @@ const ManagedVTable Managed::static_vtbl =
     0 /*markObjects*/,
     destroy,
     0 /*collectDeletables*/,
-    hasInstance,
     0,
     0,
     0,
@@ -178,11 +177,6 @@ QString Managed::className() const
     return QString::fromLatin1(s);
 }
 
-bool Managed::hasInstance(Managed *m, const ValueRef)
-{
-    return m->engine()->current->throwTypeError();
-}
-
 ReturnedValue Managed::construct(Managed *m, CallData *)
 {
     return m->engine()->current->throwTypeError();
@@ -208,11 +202,6 @@ bool Managed::isEqualTo(Managed *, Managed *)
     return false;
 }
 
-bool Managed::hasInstance(const ValueRef v)
-{
-    return vtbl->hasInstance(this, v);
-}
-
 ReturnedValue Managed::get(const StringRef name, bool *hasProperty)
 {
     return vtbl->get(this, name, hasProperty);
diff --git a/src/qml/jsruntime/qv4managed_p.h b/src/qml/jsruntime/qv4managed_p.h
index 47ac5e05e4..220363efff 100644
--- a/src/qml/jsruntime/qv4managed_p.h
+++ b/src/qml/jsruntime/qv4managed_p.h
@@ -84,7 +84,6 @@ struct ManagedVTable
     void (*markObjects)(Managed *, ExecutionEngine *e);
     void (*destroy)(Managed *);
     void (*collectDeletables)(Managed *, GCDeletable **deletable);
-    bool (*hasInstance)(Managed *, const ValueRef value);
     ReturnedValue (*get)(Managed *, const StringRef name, bool *hasProperty);
     ReturnedValue (*getIndexed)(Managed *, uint index, bool *hasProperty);
     void (*put)(Managed *, const StringRef name, const ValueRef value);
@@ -108,7 +107,6 @@ const QV4::ManagedVTable classname::static_vtbl =    \
     markObjects,                                \
     destroy,                                    \
     0,                                          \
-    hasInstance,                                \
     get,                                        \
     getIndexed,                                 \
     put,                                        \
@@ -132,7 +130,6 @@ const QV4::ManagedVTable classname::static_vtbl =    \
     markObjects,                                \
     destroy,                                    \
     collectDeletables,                          \
-    hasInstance,                                \
     get,                                        \
     getIndexed,                                 \
     put,                                        \
@@ -240,7 +237,6 @@ public:
         *reinterpret_cast<Managed **>(this) = m;
     }
 
-    bool hasInstance(const ValueRef v);
     ReturnedValue construct(CallData *d);
     ReturnedValue call(CallData *d);
     ReturnedValue get(const StringRef name, bool *hasProperty = 0);
@@ -263,7 +259,6 @@ public:
     Property *advanceIterator(ObjectIterator *it, StringRef name, uint *index, PropertyAttributes *attributes);
 
     static void destroy(Managed *that) { that->_data = 0; }
-    static bool hasInstance(Managed *that, const ValueRef value);
     static ReturnedValue construct(Managed *m, CallData *d);
     static ReturnedValue call(Managed *m, CallData *);
     static ReturnedValue getLookup(Managed *m, Lookup *);
diff --git a/src/qml/jsruntime/qv4runtime.cpp b/src/qml/jsruntime/qv4runtime.cpp
index 50fea04b2f..62923b90f9 100644
--- a/src/qml/jsruntime/qv4runtime.cpp
+++ b/src/qml/jsruntime/qv4runtime.cpp
@@ -300,12 +300,34 @@ ReturnedValue __qmljs_delete_name(ExecutionContext *ctx, const StringRef name)
 
 QV4::ReturnedValue __qmljs_instanceof(ExecutionContext *ctx, const ValueRef left, const ValueRef right)
 {
-    Object *o = right->asObject();
-    if (!o)
+    FunctionObject *f = right->asFunctionObject();
+    if (!f)
         return ctx->throwTypeError();
 
-    bool r = o->hasInstance(left);
-    return Encode(r);
+    if (f->subtype == FunctionObject::BoundFunction)
+        f = static_cast<BoundFunction *>(f)->target;
+
+    Scope scope(ctx->engine);
+    ScopedObject v(scope, left);
+    if (!v)
+        return Encode(false);
+
+    Scoped<Object> o(scope, f->protoProperty());
+    if (!o) {
+        scope.engine->current->throwTypeError();
+        return Encode(false);
+    }
+
+    while (v) {
+        v = v->prototype();
+
+        if (! v)
+            break;
+        else if (o.getPointer() == v)
+            return Encode(true);
+    }
+
+    return Encode(false);
 }
 
 QV4::ReturnedValue __qmljs_in(ExecutionContext *ctx, const ValueRef left, const ValueRef right)
diff --git a/src/qml/jsruntime/qv4string.cpp b/src/qml/jsruntime/qv4string.cpp
index 0e43d03987..7ac83ced02 100644
--- a/src/qml/jsruntime/qv4string.cpp
+++ b/src/qml/jsruntime/qv4string.cpp
@@ -108,7 +108,6 @@ const ManagedVTable String::static_vtbl =
     markObjects,
     destroy,
     0 /*collectDeletables*/,
-    hasInstance,
     get,
     getIndexed,
     put,