Bug 1055472 - Part 1: Factor out GetPrototypeFromConstructor and use it in existing object creation paths. (r=Waldo)
authorEric Faust <efaustbmo@gmail.com>
Fri, 13 Nov 2015 18:22:21 -0800
changeset 309828 e53bad3e7559113f8e974d35c62f82fdb09b42fa
parent 309827 039acf906edc14ce093663d8946920d9f696e147
child 309829 695d86baf80e80bb6642256ab836e9a26d5db05e
push id5513
push userraliiev@mozilla.com
push dateMon, 25 Jan 2016 13:55:34 +0000
treeherdermozilla-beta@5ee97dd05b5c [default view] [failures only]
perfherder[talos] [build metrics] [platform microbench] (compared to previous push)
reviewersWaldo
bugs1055472
milestone45.0a1
first release with
nightly linux32
nightly linux64
nightly mac
nightly win32
nightly win64
last release without
nightly linux32
nightly linux64
nightly mac
nightly win32
nightly win64
Bug 1055472 - Part 1: Factor out GetPrototypeFromConstructor and use it in existing object creation paths. (r=Waldo)
js/src/jsobj.cpp
js/src/jsobj.h
js/src/vm/Interpreter.cpp
--- a/js/src/jsobj.cpp
+++ b/js/src/jsobj.cpp
@@ -878,21 +878,19 @@ js::NewObjectScriptedCall(JSContext* cx,
 
     pobj.set(obj);
     return true;
 }
 
 JSObject*
 js::CreateThis(JSContext* cx, const Class* newclasp, HandleObject callee)
 {
-    RootedValue protov(cx);
-    if (!GetProperty(cx, callee, callee, cx->names().prototype, &protov))
+    RootedObject proto(cx);
+    if (!GetPrototypeFromConstructor(cx, callee, &proto))
         return nullptr;
-
-    RootedObject proto(cx, protov.isObjectOrNull() ? protov.toObjectOrNull() : nullptr);
     gc::AllocKind kind = NewObjectGCKind(newclasp);
     return NewObjectWithClassProto(cx, newclasp, proto, kind);
 }
 
 static inline JSObject*
 CreateThisForFunctionWithGroup(JSContext* cx, HandleObjectGroup group,
                                NewObjectKind newKind)
 {
@@ -984,26 +982,34 @@ js::CreateThisForFunctionWithProto(JSCon
         if (!script)
             return nullptr;
         TypeScript::SetThis(cx, script, TypeSet::ObjectType(res));
     }
 
     return res;
 }
 
+bool
+js::GetPrototypeFromConstructor(JSContext* cx, HandleObject newTarget, MutableHandleObject proto)
+{
+    RootedValue protov(cx);
+    if (!GetProperty(cx, newTarget, newTarget, cx->names().prototype, &protov))
+        return false;
+    proto.set(protov.isObject() ? &protov.toObject() : nullptr);
+    return true;
+}
+
 JSObject*
 js::CreateThisForFunction(JSContext* cx, HandleObject callee, HandleObject newTarget,
                           NewObjectKind newKind)
 {
-    RootedValue protov(cx);
-    if (!GetProperty(cx, newTarget, newTarget, cx->names().prototype, &protov))
+    RootedObject proto(cx);
+    if (!GetPrototypeFromConstructor(cx, newTarget, &proto))
         return nullptr;
-    RootedObject proto(cx);
-    if (protov.isObject())
-        proto = &protov.toObject();
+
     JSObject* obj = CreateThisForFunctionWithProto(cx, callee, newTarget, proto, newKind);
 
     if (obj && newKind == SingletonObject) {
         RootedPlainObject nobj(cx, &obj->as<PlainObject>());
 
         /* Reshape the singleton before passing it as the 'this' value. */
         NativeObject::clear(cx, nobj);
 
--- a/js/src/jsobj.h
+++ b/js/src/jsobj.h
@@ -1084,16 +1084,20 @@ GetInitialHeap(NewObjectKind newKind, co
 {
     if (newKind != GenericObject)
         return gc::TenuredHeap;
     if (clasp->finalize && !(clasp->flags & JSCLASS_SKIP_NURSERY_FINALIZE))
         return gc::TenuredHeap;
     return gc::DefaultHeap;
 }
 
+// ES6 9.1.15 GetPrototypeFromConstructor.
+extern bool
+GetPrototypeFromConstructor(JSContext* cx, js::HandleObject newTarget, js::MutableHandleObject proto);
+
 // Specialized call for constructing |this| with a known function callee,
 // and a known prototype.
 extern JSObject*
 CreateThisForFunctionWithProto(JSContext* cx, js::HandleObject callee, HandleObject newTarget,
                                HandleObject proto, NewObjectKind newKind = GenericObject);
 
 // Specialized call for constructing |this| with a known function callee.
 extern JSObject*
--- a/js/src/vm/Interpreter.cpp
+++ b/js/src/vm/Interpreter.cpp
@@ -4765,30 +4765,17 @@ js::DefaultClassConstructor(JSContext* c
 {
     CallArgs args = CallArgsFromVp(argc, vp);
     if (!args.isConstructing()) {
         JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_CANT_CALL_CLASS_CONSTRUCTOR);
         return false;
     }
 
     RootedObject newTarget(cx, &args.newTarget().toObject());
-    RootedValue protoVal(cx);
-
-    if (!GetProperty(cx, newTarget, newTarget, cx->names().prototype, &protoVal))
-        return false;
-
-    RootedObject proto(cx);
-    if (!protoVal.isObject()) {
-        if (!GetBuiltinPrototype(cx, JSProto_Object, &proto))
-            return false;
-    } else {
-        proto = &protoVal.toObject();
-    }
-
-    JSObject* obj = NewObjectWithGivenProto(cx, &PlainObject::class_, proto);
+    JSObject* obj = CreateThis(cx, &PlainObject::class_, newTarget);
     if (!obj)
         return false;
 
     args.rval().set(ObjectValue(*obj));
     return true;
 }
 
 bool