Minor performance improvements to the LookupIterator

This change changes bootstrapping semantics for intercepted global objects. Unlike before, we'll now also call into the interceptor during bootstrapping. This affects properties loaded from within the runtime, such as global.Array and global.Symbol. The embedder will need to make sure that those values are the expected values during bootstrapping.

BUG=chromium:505998
LOG=n

Review URL: https://codereview.chromium.org/1220813005

Cr-Commit-Position: refs/heads/master@{#29414}

src/lookup-inl.h

@@ -15,7 +15,7 @@ namespace internal {
 
 JSReceiver* LookupIterator::NextHolder(Map* map) {
   DisallowHeapAllocation no_gc;
-  if (map->prototype()->IsNull()) return NULL;
+  if (!map->prototype()->IsJSReceiver()) return NULL;
 
   JSReceiver* next = JSReceiver::cast(map->prototype());
   DCHECK(!next->map()->IsGlobalObjectMap() ||

src/lookup.cc

@@ -87,11 +87,6 @@ Handle<JSObject> LookupIterator::GetStoreTarget() const {
 }
 
 
-bool LookupIterator::IsBootstrapping() const {
-  return isolate_->bootstrapper()->IsActive();
-}
-
-
 bool LookupIterator::HasAccess() const {
   DCHECK_EQ(ACCESS_CHECK, state_);
   return isolate_->MayAccess(GetHolder<JSObject>());

src/lookup.h

@@ -259,11 +259,9 @@ class LookupIterator final BASE_EMBEDDED {
   bool InternalHolderIsReceiverOrHiddenPrototype() const;
   InterceptorInfo* GetInterceptor(JSObject* holder) const;
 
-  bool IsBootstrapping() const;
-
   bool check_hidden() const { return (configuration_ & kHidden) != 0; }
   bool check_interceptor() const {
-    return !IsBootstrapping() && (configuration_ & kInterceptor) != 0;
+    return (configuration_ & kInterceptor) != 0;
   }
   bool check_prototype_chain() const {
     return (configuration_ & kPrototypeChain) != 0;

test/cctest/test-api.cc

@@ -13273,18 +13273,19 @@ TEST(ForceSet) {
 
 
 TEST(ForceSetWithInterceptor) {
-  force_set_get_count = 0;
-  force_set_set_count = 0;
-  pass_on_get = false;
-
   v8::Isolate* isolate = CcTest::isolate();
   v8::HandleScope scope(isolate);
   v8::Handle<v8::ObjectTemplate> templ = v8::ObjectTemplate::New(isolate);
   templ->SetHandler(v8::NamedPropertyHandlerConfiguration(
       ForceSetInterceptGetter, ForceSetInterceptSetter));
+  pass_on_get = true;
   LocalContext context(NULL, templ);
   v8::Handle<v8::Object> global = context->Global();
 
+  force_set_get_count = 0;
+  force_set_set_count = 0;
+  pass_on_get = false;
+
   v8::Handle<v8::String> some_property =
       v8::String::NewFromUtf8(isolate, "a");
   CHECK_EQ(0, force_set_set_count);

test/cctest/test-decls.cc

@@ -130,6 +130,10 @@ void DeclarationContext::InitializeIfNeeded() {
   context_.Reset(isolate, context);
   context->Enter();
   is_initialized_ = true;
+  // Reset counts. Bootstrapping might have called into the interceptor.
+  get_count_ = 0;
+  set_count_ = 0;
+  query_count_ = 0;
   PostInitializeContext(context);
 }