Bug 725888 - Remove some js_GetClassPrototype calls, using faster methods on GlobalObject instead. Also introduce JS_GetObjectPrototype to retrieve Object.prototype so that a friend API can be made un-friendly. r=dmandelin

--HG--
extra : rebase_source : d68d7f1fdcc1bc9a1a027c08ea62bebd8e9d0178

js/src/jsapi.cpp

@@ -2172,6 +2172,14 @@ JS_GetClassObject(JSContext *cx, JSObject *obj, JSProtoKey key, JSObject **objp)
     return js_GetClassObject(cx, obj, key, objp);
 }
 
+JS_PUBLIC_API(JSObject *)
+JS_GetObjectPrototype(JSContext *cx, JSObject *forObj)
+{
+    CHECK_REQUEST(cx);
+    assertSameCompartment(cx, forObj);
+    return forObj->global().getOrCreateObjectPrototype(cx);
+}
+
 JS_PUBLIC_API(JSObject *)
 JS_GetGlobalForObject(JSContext *cx, JSObject *obj)
 {

js/src/jsapi.h

@@ -2728,6 +2728,13 @@ extern JS_PUBLIC_API(JSBool)
 JS_GetClassObject(JSContext *cx, JSObject *obj, JSProtoKey key,
                   JSObject **objp);
 
+/*
+ * Returns the original value of |Object.prototype| from the global object in
+ * which |forObj| was created.
+ */
+extern JS_PUBLIC_API(JSObject *)
+JS_GetObjectPrototype(JSContext *cx, JSObject *forObj);
+
 extern JS_PUBLIC_API(JSObject *)
 JS_GetGlobalForObject(JSContext *cx, JSObject *obj);
 

js/src/jsexn.cpp

@@ -971,14 +971,6 @@ JS_STATIC_ASSERT(JSProto_Error + JSEXN_SYNTAXERR    == JSProto_SyntaxError);
 JS_STATIC_ASSERT(JSProto_Error + JSEXN_TYPEERR      == JSProto_TypeError);
 JS_STATIC_ASSERT(JSProto_Error + JSEXN_URIERR       == JSProto_URIError);
 
-static JS_INLINE JSProtoKey
-GetExceptionProtoKey(intN exn)
-{
-    JS_ASSERT(JSEXN_ERR <= exn);
-    JS_ASSERT(exn < JSEXN_LIMIT);
-    return JSProtoKey(JSProto_Error + exn);
-}
-
 static JSObject *
 InitErrorClass(JSContext *cx, GlobalObject *global, intN type, JSObject &proto)
 {
@@ -1031,8 +1023,8 @@ js_InitExceptionClasses(JSContext *cx, JSObject *obj)
 
     GlobalObject *global = &obj->asGlobal();
 
-    JSObject *objectProto;
-    if (!js_GetClassPrototype(cx, global, JSProto_Object, &objectProto))
+    JSObject *objectProto = global->getOrCreateObjectPrototype(cx);
+    if (!objectProto)
         return NULL;
 
     /* Initialize the base Error class first. */
@@ -1331,8 +1323,8 @@ js_CopyErrorObject(JSContext *cx, JSObject *errobj, JSObject *scope)
     copy->exnType = priv->exnType;
 
     // Create the Error object.
-    JSObject *proto;
-    if (!js_GetClassPrototype(cx, &scope->global(), GetExceptionProtoKey(copy->exnType), &proto))
+    JSObject *proto = scope->global().getOrCreateCustomErrorPrototype(cx, copy->exnType);
+    if (!proto)
         return NULL;
     JSObject *copyobj = NewObjectWithGivenProto(cx, &ErrorClass, proto, NULL);
     SetExnPrivate(cx, copyobj, copy);

js/src/jsexn.h

@@ -101,4 +101,12 @@ js_GetLocalizedErrorMessage(JSContext* cx, void *userRef, const char *locale,
 extern JSObject *
 js_CopyErrorObject(JSContext *cx, JSObject *errobj, JSObject *scope);
 
+static JS_INLINE JSProtoKey
+GetExceptionProtoKey(intN exn)
+{
+    JS_ASSERT(JSEXN_ERR <= exn);
+    JS_ASSERT(exn < JSEXN_LIMIT);
+    return JSProtoKey(JSProto_Error + exn);
+}
+
 #endif /* jsexn_h___ */

js/src/jsfriendapi.h

@@ -755,14 +755,6 @@ class ObjectPtr
 
 } /* namespace js */
 
-/*
- * If protoKey is not JSProto_Null, then clasp is ignored. If protoKey is
- * JSProto_Null, clasp must non-null.
- */
-extern JS_FRIEND_API(JSBool)
-js_GetClassPrototype(JSContext *cx, JSObject *scope, JSProtoKey protoKey,
-                     JSObject **protop, js::Class *clasp = NULL);
-
 #endif
 
 /* Implemented in jsdate.cpp. */

js/src/jsfun.cpp

@@ -1244,8 +1244,8 @@ ResolveInterpretedFunctionPrototype(JSContext *cx, JSObject *obj)
      * Make the prototype object an instance of Object with the same parent
      * as the function object itself.
      */
-    JSObject *objProto;
-    if (!js_GetClassPrototype(cx, obj->getParent(), JSProto_Object, &objProto))
+    JSObject *objProto = obj->global().getOrCreateObjectPrototype(cx);
+    if (!objProto)
         return NULL;
     JSObject *proto = NewObjectWithGivenProto(cx, &ObjectClass, objProto, NULL);
     if (!proto || !proto->setSingletonType(cx))

js/src/jsinfer.cpp

@@ -2094,11 +2094,11 @@ types::ArrayPrototypeHasIndexedProperty(JSContext *cx, JSScript *script)
     if (!cx->typeInferenceEnabled() || !script->hasGlobal())
         return true;
 
-    JSObject *proto;
-    if (!js_GetClassPrototype(cx, NULL, JSProto_Array, &proto, NULL))
+    JSObject *proto = script->global()->getOrCreateArrayPrototype(cx);
+    if (!proto)
         return true;
 
-    while (proto) {
+    do {
         TypeObject *type = proto->getType(cx);
         if (type->unknownProperties())
             return true;
@@ -2106,7 +2106,7 @@ types::ArrayPrototypeHasIndexedProperty(JSContext *cx, JSScript *script)
         if (!indexTypes || indexTypes->isOwnProperty(cx, type, true) || indexTypes->knownNonEmpty(cx))
             return true;
         proto = proto->getProto();
-    }
+    } while (proto);
 
     return false;
 }

js/src/jsinterp.cpp

@@ -2612,7 +2612,7 @@ BEGIN_CASE(JSOP_CALLELEM)
 {
     /* Find the object on which to look for |this|'s properties. */
     Value thisv = regs.sp[-2];
-    JSObject *thisObj = ValuePropertyBearer(cx, thisv, -2);
+    JSObject *thisObj = ValuePropertyBearer(cx, regs.fp(), thisv, -2);
     if (!thisObj)
         goto error;
 

js/src/jsinterpinlines.h

@@ -153,28 +153,23 @@ ComputeThis(JSContext *cx, StackFrame *fp)
  * problem to the value at |spindex| on the stack.
  */
 JS_ALWAYS_INLINE JSObject *
-ValuePropertyBearer(JSContext *cx, const Value &v, int spindex)
+ValuePropertyBearer(JSContext *cx, StackFrame *fp, const Value &v, int spindex)
 {
     if (v.isObject())
         return &v.toObject();
 
-    JSProtoKey protoKey;
-    if (v.isString()) {
-        protoKey = JSProto_String;
-    } else if (v.isNumber()) {
-        protoKey = JSProto_Number;
-    } else if (v.isBoolean()) {
-        protoKey = JSProto_Boolean;
-    } else {
-        JS_ASSERT(v.isNull() || v.isUndefined());
-        js_ReportIsNullOrUndefined(cx, spindex, v, NULL);
-        return NULL;
-    }
+    GlobalObject &global = fp->scopeChain().global();
 
-    JSObject *pobj;
-    if (!js_GetClassPrototype(cx, NULL, protoKey, &pobj))
-        return NULL;
-    return pobj;
+    if (v.isString())
+        return global.getOrCreateStringPrototype(cx);
+    if (v.isNumber())
+        return global.getOrCreateNumberPrototype(cx);
+    if (v.isBoolean())
+        return global.getOrCreateBooleanPrototype(cx);
+
+    JS_ASSERT(v.isNull() || v.isUndefined());
+    js_ReportIsNullOrUndefined(cx, spindex, v, NULL);
+    return NULL;
 }
 
 inline bool

js/src/jsobj.h

@@ -2000,6 +2000,17 @@ js_InferFlags(JSContext *cx, uintN defaultFlags);
 JSBool
 js_Object(JSContext *cx, uintN argc, js::Value *vp);
 
+/*
+ * If protoKey is not JSProto_Null, then clasp is ignored. If protoKey is
+ * JSProto_Null, clasp must non-null.
+ *
+ * If protoKey is constant and scope is non-null, use GlobalObject's prototype
+ * methods instead.
+ */
+extern JS_FRIEND_API(JSBool)
+js_GetClassPrototype(JSContext *cx, JSObject *scope, JSProtoKey protoKey,
+                     JSObject **protop, js::Class *clasp = NULL);
+
 namespace js {
 
 extern bool

js/src/methodjit/Compiler.cpp

@@ -4507,8 +4507,8 @@ mjit::Compiler::callArrayBuiltin(uint32_t argc, bool callingNew)
     if (!js_GetClassObject(cx, globalObj, JSProto_Array, &arrayObj))
         return Compile_Error;
 
-    JSObject *arrayProto;
-    if (!js_GetClassPrototype(cx, globalObj, JSProto_Array, &arrayProto))
+    JSObject *arrayProto = globalObj->global().getOrCreateArrayPrototype(cx);
+    if (!arrayProto)
         return Compile_Error;
 
     if (argc > 1)

js/src/methodjit/FastOps.cpp

@@ -1518,8 +1518,8 @@ GetDenseArrayShape(JSContext *cx, JSObject *globalObj)
 {
     JS_ASSERT(globalObj);
 
-    JSObject *proto;
-    if (!js_GetClassPrototype(cx, globalObj, JSProto_Array, &proto, NULL))
+    JSObject *proto = globalObj->global().getOrCreateArrayPrototype(cx);
+    if (!proto)
         return NULL;
 
     return EmptyShape::getInitialShape(cx, &ArrayClass, proto,

js/src/vm/Debugger.cpp

@@ -2633,8 +2633,8 @@ DebuggerFrame_getArguments(JSContext *cx, uintN argc, Value *vp)
         /* Create an arguments object. */
         RootedVar<GlobalObject*> global(cx);
         global = &args.callee().global();
-        JSObject *proto;
-        if (!js_GetClassPrototype(cx, global, JSProto_Array, &proto))
+        JSObject *proto = global->getOrCreateArrayPrototype(cx);
+        if (!proto)
             return false;
         argsobj = NewObjectWithGivenProto(cx, &DebuggerArguments_class, proto, global);
         if (!argsobj)
@@ -3791,7 +3791,8 @@ JS_DefineDebuggerObject(JSContext *cx, JSObject *obj)
         scriptProto(cx),
         objectProto(cx);
 
-    if (!js_GetClassPrototype(cx, obj, JSProto_Object, objProto.address()))
+    objProto = obj->asGlobal().getOrCreateObjectPrototype(cx);
+    if (!objProto)
         return false;
 
 

js/src/vm/GlobalObject.h

@@ -45,6 +45,7 @@
 
 #include "jsarray.h"
 #include "jsbool.h"
+#include "jsexn.h"
 #include "jsfun.h"
 #include "jsiter.h"
 #include "jsnum.h"
@@ -186,6 +187,9 @@ class GlobalObject : public JSObject {
     bool arrayBufferClassInitialized() const {
         return classIsInitialized(JSProto_ArrayBuffer);
     }
+    bool errorClassesInitialized() const {
+        return classIsInitialized(JSProto_Error);
+    }
 
   public:
     static GlobalObject *create(JSContext *cx, Class *clasp);
@@ -294,6 +298,17 @@ class GlobalObject : public JSObject {
         return &self->getPrototype(JSProto_ArrayBuffer).toObject();
     }
 
+    JSObject *getOrCreateCustomErrorPrototype(JSContext *cx, intN exnType) {
+        GlobalObject *self = this;
+        JSProtoKey key = GetExceptionProtoKey(exnType);
+        if (!errorClassesInitialized()) {
+            Root<GlobalObject*> root(cx, &self);
+            if (!js_InitExceptionClasses(cx, this))
+                return NULL;
+        }
+        return &self->getPrototype(key).toObject();
+    }
+
     JSObject *getOrCreateGeneratorPrototype(JSContext *cx) {
         GlobalObject *self = this;
         Value v = getSlotRef(GENERATOR_PROTO);

js/xpconnect/src/dombindings.cpp

@@ -1312,10 +1312,7 @@ NoBase::getPrototype(JSContext *cx, XPCWrappedNativeScope *scope)
     // We need to pass the object prototype to JS_NewObject. If we pass NULL then the JS engine
     // will look up a prototype on the global by using the class' name and we'll recurse into
     // getPrototype.
-    JSObject* proto;
-    if (!js_GetClassPrototype(cx, scope->GetGlobalJSObject(), JSProto_Object, &proto))
-        return NULL;
-    return proto;
+    return JS_GetObjectPrototype(cx, scope->GetGlobalJSObject());
 }