[modules] Remove @@iterator on namespace objects.

TC39 decided at their last meeting to remove this feature.

R=adamk@chromium.org
TBR=ulan@chromium.org
BUG=v8:1569

Review-Url: https://codereview.chromium.org/2578053003
Cr-Commit-Position: refs/heads/master@{#41745}

src/ast/ast-types.cc

@@ -209,7 +209,6 @@ AstType::bitset AstBitsetType::Lub(i::Map* map) {
     case JS_CONTEXT_EXTENSION_OBJECT_TYPE:
     case JS_GENERATOR_OBJECT_TYPE:
     case JS_MODULE_NAMESPACE_TYPE:
-    case JS_FIXED_ARRAY_ITERATOR_TYPE:
     case JS_ARRAY_BUFFER_TYPE:
     case JS_ARRAY_TYPE:
     case JS_REGEXP_TYPE:  // TODO(rossberg): there should be a RegExp type.

src/bootstrapper.cc

@@ -2475,7 +2475,7 @@ void Genesis::InitializeGlobal(Handle<JSGlobalObject> global_object,
     Handle<Map> map =
         factory->NewMap(JS_MODULE_NAMESPACE_TYPE, JSModuleNamespace::kSize);
     Map::SetPrototype(map, isolate->factory()->null_value());
-    Map::EnsureDescriptorSlack(map, 2);
+    Map::EnsureDescriptorSlack(map, 1);
     native_context()->set_js_module_namespace_map(*map);
 
     {  // Install @@toStringTag.
@@ -2486,16 +2486,6 @@ void Genesis::InitializeGlobal(Handle<JSGlobalObject> global_object,
                                attribs);
       map->AppendDescriptor(&d);
     }
-
-    {  // Install @@iterator.
-      Handle<JSFunction> iterator = SimpleCreateFunction(
-          isolate, factory->NewStringFromAsciiChecked("[Symbol.iterator]"),
-          Builtins::kModuleNamespaceIterator, 0, true);
-      iterator->shared()->set_native(true);
-      // TODO(neis): Is this really supposed to be writable?
-      DataConstantDescriptor d(factory->iterator_symbol(), iterator, DONT_ENUM);
-      map->AppendDescriptor(&d);
-    }
   }
 
   {  // -- I t e r a t o r R e s u l t
@@ -3091,25 +3081,6 @@ void Bootstrapper::ExportFromRuntime(Isolate* isolate,
         *generator_function_function);
   }
 
-  {  // -- F i x e d A r r a y I t e r a t o r
-    int size = JSFixedArrayIterator::kHeaderSize +
-               JSFixedArrayIterator::kInObjectPropertyCount * kPointerSize;
-    Handle<Map> map = factory->NewMap(JS_FIXED_ARRAY_ITERATOR_TYPE, size);
-    Map::SetPrototype(map, iterator_prototype);
-    Map::EnsureDescriptorSlack(map,
-                               JSFixedArrayIterator::kInObjectPropertyCount);
-    map->SetInObjectProperties(JSFixedArrayIterator::kInObjectPropertyCount);
-    map->SetConstructor(native_context->object_function());
-
-    {  // next
-      DataDescriptor d(factory->next_string(), JSFixedArrayIterator::kNextIndex,
-                       DONT_ENUM, Representation::Tagged());
-      map->AppendDescriptor(&d);
-    }
-
-    native_context->set_fixed_array_iterator_map(*map);
-  }
-
   {  // -- S e t I t e r a t o r
     Handle<JSObject> set_iterator_prototype =
         isolate->factory()->NewJSObject(isolate->object_function(), TENURED);

src/builtins/builtins-iterator.cc

@@ -16,55 +16,5 @@ void Builtins::Generate_IteratorPrototypeIterator(
   assembler.Return(assembler.Parameter(0));
 }
 
-BUILTIN(ModuleNamespaceIterator) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-  Handle<Object> receiver = args.at<Object>(0);
-
-  if (!receiver->IsJSModuleNamespace()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kIncompatibleMethodReceiver,
-                              isolate->factory()->iterator_symbol(), receiver));
-  }
-  auto ns = Handle<JSModuleNamespace>::cast(receiver);
-
-  Handle<FixedArray> names =
-      KeyAccumulator::GetKeys(ns, KeyCollectionMode::kOwnOnly, SKIP_SYMBOLS)
-          .ToHandleChecked();
-  return *isolate->factory()->NewJSFixedArrayIterator(names);
-}
-
-BUILTIN(FixedArrayIteratorNext) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-  Handle<Object> receiver = args.at<Object>(0);
-
-  // It is an error if this function is called on anything other than the
-  // particular iterator object for which the function was created.
-  if (!receiver->IsJSFixedArrayIterator() ||
-      Handle<JSFixedArrayIterator>::cast(receiver)->initial_next() !=
-          *args.target()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kIncompatibleMethodReceiver,
-                              isolate->factory()->next_string(), receiver));
-  }
-
-  auto iterator = Handle<JSFixedArrayIterator>::cast(receiver);
-  Handle<Object> value;
-  bool done;
-
-  int index = iterator->index();
-  if (index < iterator->array()->length()) {
-    value = handle(iterator->array()->get(index), isolate);
-    done = false;
-    iterator->set_index(index + 1);
-  } else {
-    value = isolate->factory()->undefined_value();
-    done = true;
-  }
-
-  return *isolate->factory()->NewJSIteratorResult(value, done);
-}
-
 }  // namespace internal
 }  // namespace v8

src/builtins/builtins.h

@@ -711,9 +711,6 @@ namespace internal {
   TFJ(TypedArrayPrototypeKeys, 0)                                             \
   /* ES6 #sec-%typedarray%.prototype.values */                                \
   TFJ(TypedArrayPrototypeValues, 0)                                           \
-                                                                              \
-  CPP(ModuleNamespaceIterator)                                                \
-  CPP(FixedArrayIteratorNext)
 
 #define IGNORE_BUILTIN(...)
 

src/compiler/types.cc

@@ -214,7 +214,6 @@ Type::bitset BitsetType::Lub(i::Map* map) {
     case JS_CONTEXT_EXTENSION_OBJECT_TYPE:
     case JS_GENERATOR_OBJECT_TYPE:
     case JS_MODULE_NAMESPACE_TYPE:
-    case JS_FIXED_ARRAY_ITERATOR_TYPE:
     case JS_ARRAY_BUFFER_TYPE:
     case JS_ARRAY_TYPE:
     case JS_REGEXP_TYPE:  // TODO(rossberg): there should be a RegExp type.

src/contexts.h

@@ -231,7 +231,6 @@ enum ContextLookupFlags {
   V(FAST_ALIASED_ARGUMENTS_MAP_INDEX, Map, fast_aliased_arguments_map)         \
   V(FAST_TEMPLATE_INSTANTIATIONS_CACHE_INDEX, FixedArray,                      \
     fast_template_instantiations_cache)                                        \
-  V(FIXED_ARRAY_ITERATOR_MAP_INDEX, Map, fixed_array_iterator_map)             \
   V(FLOAT32_ARRAY_FUN_INDEX, JSFunction, float32_array_fun)                    \
   V(FLOAT32X4_FUNCTION_INDEX, JSFunction, float32x4_function)                  \
   V(FLOAT64_ARRAY_FUN_INDEX, JSFunction, float64_array_fun)                    \

src/factory.cc

@@ -2764,26 +2764,5 @@ void Factory::SetClassFunctionInstanceDescriptor(Handle<Map> map) {
   }
 }
 
-Handle<JSFixedArrayIterator> Factory::NewJSFixedArrayIterator(
-    Handle<FixedArray> array) {
-  // Create the "next" function (must be unique per iterator object).
-  Handle<Code> code(
-      isolate()->builtins()->builtin(Builtins::kFixedArrayIteratorNext));
-  // TODO(neis): Don't create a new SharedFunctionInfo each time.
-  Handle<JSFunction> next = isolate()->factory()->NewFunctionWithoutPrototype(
-      isolate()->factory()->next_string(), code, false);
-  next->shared()->set_native(true);
-
-  // Create the iterator.
-  Handle<Map> map(isolate()->native_context()->fixed_array_iterator_map());
-  Handle<JSFixedArrayIterator> iterator =
-      Handle<JSFixedArrayIterator>::cast(NewJSObjectFromMap(map));
-  iterator->set_initial_next(*next);
-  iterator->set_array(*array);
-  iterator->set_index(0);
-  iterator->InObjectPropertyAtPut(JSFixedArrayIterator::kNextIndex, *next);
-  return iterator;
-}
-
 }  // namespace internal
 }  // namespace v8

src/factory.h

@@ -543,9 +543,6 @@ class V8_EXPORT_PRIVATE Factory final {
   Handle<JSMapIterator> NewJSMapIterator();
   Handle<JSSetIterator> NewJSSetIterator();
 
-  Handle<JSFixedArrayIterator> NewJSFixedArrayIterator(
-      Handle<FixedArray> array);
-
   // Allocates a bound function.
   MaybeHandle<JSBoundFunction> NewJSBoundFunction(
       Handle<JSReceiver> target_function, Handle<Object> bound_this,

src/heap/objects-visiting.cc

@@ -107,7 +107,6 @@ StaticVisitorBase::VisitorId StaticVisitorBase::GetVisitorId(
     case JS_ARGUMENTS_TYPE:
     case JS_CONTEXT_EXTENSION_OBJECT_TYPE:
     case JS_GENERATOR_OBJECT_TYPE:
-    case JS_FIXED_ARRAY_ITERATOR_TYPE:
     case JS_MODULE_NAMESPACE_TYPE:
     case JS_VALUE_TYPE:
     case JS_DATE_TYPE:

src/objects-body-descriptors-inl.h

@@ -469,7 +469,6 @@ ReturnType BodyDescriptorApply(InstanceType type, T1 p1, T2 p2, T3 p3) {
     case JS_DATE_TYPE:
     case JS_ARRAY_TYPE:
     case JS_MODULE_NAMESPACE_TYPE:
-    case JS_FIXED_ARRAY_ITERATOR_TYPE:
     case JS_TYPED_ARRAY_TYPE:
     case JS_DATA_VIEW_TYPE:
     case JS_SET_TYPE:

src/objects-debug.cc

@@ -142,9 +142,6 @@ void HeapObject::HeapObjectVerify() {
     case JS_MODULE_NAMESPACE_TYPE:
       JSModuleNamespace::cast(this)->JSModuleNamespaceVerify();
       break;
-    case JS_FIXED_ARRAY_ITERATOR_TYPE:
-      JSFixedArrayIterator::cast(this)->JSFixedArrayIteratorVerify();
-      break;
     case JS_SET_TYPE:
       JSSet::cast(this)->JSSetVerify();
       break;
@@ -1039,16 +1036,6 @@ void JSModuleNamespace::JSModuleNamespaceVerify() {
   VerifyPointer(module());
 }
 
-void JSFixedArrayIterator::JSFixedArrayIteratorVerify() {
-  CHECK(IsJSFixedArrayIterator());
-
-  VerifyPointer(array());
-  VerifyPointer(initial_next());
-  VerifySmiField(kIndexOffset);
-
-  CHECK_LE(index(), array()->length());
-}
-
 void ModuleInfoEntry::ModuleInfoEntryVerify() {
   Isolate* isolate = GetIsolate();
   CHECK(IsModuleInfoEntry());

src/objects-inl.h

@@ -708,7 +708,6 @@ TYPE_CHECKER(FixedDoubleArray, FIXED_DOUBLE_ARRAY_TYPE)
 TYPE_CHECKER(WeakFixedArray, FIXED_ARRAY_TYPE)
 TYPE_CHECKER(TransitionArray, TRANSITION_ARRAY_TYPE)
 TYPE_CHECKER(JSStringIterator, JS_STRING_ITERATOR_TYPE)
-TYPE_CHECKER(JSFixedArrayIterator, JS_FIXED_ARRAY_ITERATOR_TYPE)
 
 bool HeapObject::IsJSWeakCollection() const {
   return IsJSWeakMap() || IsJSWeakSet();
@@ -2106,8 +2105,6 @@ int JSObject::GetHeaderSize(InstanceType type) {
       return JSObject::kHeaderSize;
     case JS_STRING_ITERATOR_TYPE:
       return JSStringIterator::kSize;
-    case JS_FIXED_ARRAY_ITERATOR_TYPE:
-      return JSFixedArrayIterator::kHeaderSize;
     case JS_MODULE_NAMESPACE_TYPE:
       return JSModuleNamespace::kSize;
     default:
@@ -3319,7 +3316,6 @@ CAST_ACCESSOR(JSMap)
 CAST_ACCESSOR(JSMapIterator)
 CAST_ACCESSOR(JSMessageObject)
 CAST_ACCESSOR(JSModuleNamespace)
-CAST_ACCESSOR(JSFixedArrayIterator)
 CAST_ACCESSOR(JSObject)
 CAST_ACCESSOR(JSProxy)
 CAST_ACCESSOR(JSReceiver)
@@ -5812,10 +5808,6 @@ ACCESSORS(ContextExtension, extension, Object, kExtensionOffset)
 
 ACCESSORS(JSModuleNamespace, module, Module, kModuleOffset)
 
-ACCESSORS(JSFixedArrayIterator, array, FixedArray, kArrayOffset)
-SMI_ACCESSORS(JSFixedArrayIterator, index, kIndexOffset)
-ACCESSORS(JSFixedArrayIterator, initial_next, JSFunction, kNextOffset)
-
 ACCESSORS(Module, code, Object, kCodeOffset)
 ACCESSORS(Module, exports, ObjectHashTable, kExportsOffset)
 ACCESSORS(Module, regular_exports, FixedArray, kRegularExportsOffset)

src/objects-printer.cc

@@ -235,9 +235,6 @@ void HeapObject::HeapObjectPrint(std::ostream& os) {  // NOLINT
     case JS_TYPED_ARRAY_TYPE:
       JSTypedArray::cast(this)->JSTypedArrayPrint(os);
       break;
-    case JS_FIXED_ARRAY_ITERATOR_TYPE:
-      JSFixedArrayIterator::cast(this)->JSFixedArrayIteratorPrint(os);
-      break;
     case JS_DATA_VIEW_TYPE:
       JSDataView::cast(this)->JSDataViewPrint(os);
       break;
@@ -1013,15 +1010,6 @@ void JSArrayIterator::JSArrayIteratorPrint(std::ostream& os) {  // NOLING
   JSObjectPrintBody(os, this);
 }
 
-void JSFixedArrayIterator::JSFixedArrayIteratorPrint(
-    std::ostream& os) {  // NOLINT
-  JSObjectPrintHeader(os, this, "JSFixedArrayIterator");
-  os << "\n - array = " << Brief(array());
-  os << "\n - index = " << index();
-  os << "\n - initial_next = " << Brief(initial_next());
-  JSObjectPrintBody(os, this);
-}
-
 void JSDataView::JSDataViewPrint(std::ostream& os) {  // NOLINT
   JSObjectPrintHeader(os, this, "JSDataView");
   os << "\n - buffer =" << Brief(buffer());

src/objects.h

@@ -72,7 +72,6 @@
 //           - JSDate
 //         - JSMessageObject
 //         - JSModuleNamespace
-//         - JSFixedArrayIterator
 //       - JSProxy
 //     - FixedArrayBase
 //       - ByteArray
@@ -410,7 +409,6 @@ const int kStubMinorKeyBits = kSmiValueSize - kStubMajorKeyBits - 1;
   V(JS_CONTEXT_EXTENSION_OBJECT_TYPE)                           \
   V(JS_GENERATOR_OBJECT_TYPE)                                   \
   V(JS_MODULE_NAMESPACE_TYPE)                                   \
-  V(JS_FIXED_ARRAY_ITERATOR_TYPE)                               \
   V(JS_GLOBAL_OBJECT_TYPE)                                      \
   V(JS_GLOBAL_PROXY_TYPE)                                       \
   V(JS_API_OBJECT_TYPE)                                         \
@@ -763,7 +761,6 @@ enum InstanceType {
   JS_CONTEXT_EXTENSION_OBJECT_TYPE,
   JS_GENERATOR_OBJECT_TYPE,
   JS_MODULE_NAMESPACE_TYPE,
-  JS_FIXED_ARRAY_ITERATOR_TYPE,
   JS_ARRAY_TYPE,
   JS_ARRAY_BUFFER_TYPE,
   JS_TYPED_ARRAY_TYPE,
@@ -1072,7 +1069,6 @@ template <class C> inline bool Is(Object* obj);
   V(JSContextExtensionObject)    \
   V(JSGeneratorObject)           \
   V(JSModuleNamespace)           \
-  V(JSFixedArrayIterator)        \
   V(Map)                         \
   V(DescriptorArray)             \
   V(FrameArray)                  \
@@ -10931,37 +10927,6 @@ class JSStringIterator : public JSObject {
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSStringIterator);
 };
 
-// A JS iterator over the elements of a FixedArray.
-// This corresponds to ListIterator in ecma262/#sec-createlistiterator.
-class JSFixedArrayIterator : public JSObject {
- public:
-  DECLARE_CAST(JSFixedArrayIterator)
-  DECLARE_PRINTER(JSFixedArrayIterator)
-  DECLARE_VERIFIER(JSFixedArrayIterator)
-
-  // The array over which the iterator iterates.
-  DECL_ACCESSORS(array, FixedArray)
-
-  // The index of the array element that will be returned next.
-  DECL_INT_ACCESSORS(index)
-
-  // The initial value of the object's "next" property.
-  DECL_ACCESSORS(initial_next, JSFunction)
-
-  static const int kArrayOffset = JSObject::kHeaderSize;
-  static const int kIndexOffset = kArrayOffset + kPointerSize;
-  static const int kNextOffset = kIndexOffset + kPointerSize;
-  static const int kHeaderSize = kNextOffset + kPointerSize;
-
-  enum InObjectPropertyIndex {
-    kNextIndex,
-    kInObjectPropertyCount  // Dummy.
-  };
-
- private:
-  DISALLOW_IMPLICIT_CONSTRUCTORS(JSFixedArrayIterator);
-};
-
 // OrderedHashTableIterator is an iterator that iterates over the keys and
 // values of an OrderedHashTable.
 //

test/cctest/interpreter/bytecode_expectations/CallRuntime.golden

@@ -79,7 +79,7 @@ bytecodes: [
                 B(Star), R(0),
                 B(CreateArrayLiteral), U8(0), U8(0), U8(9),
                 B(Star), R(1),
-                B(CallJSRuntime), U8(157), R(0), U8(2),
+                B(CallJSRuntime), U8(156), R(0), U8(2),
   /*   44 S> */ B(Return),
 ]
 constant pool: [

test/cctest/interpreter/bytecode_expectations/SuperCallAndSpread.golden

@@ -126,14 +126,14 @@ bytecodes: [
                 B(LdaUndefined),
                 B(Star), R(7),
                 B(Mov), R(2), R(8),
-  /*  152 E> */ B(CallJSRuntime), U8(157), R(7), U8(2),
+  /*  152 E> */ B(CallJSRuntime), U8(156), R(7), U8(2),
                 B(Star), R(7),
                 B(CreateArrayLiteral), U8(1), U8(1), U8(9),
                 B(Star), R(8),
-                B(CallJSRuntime), U8(156), R(5), U8(4),
+                B(CallJSRuntime), U8(155), R(5), U8(4),
                 B(Star), R(5),
                 B(Mov), R(0), R(6),
-  /*  140 E> */ B(CallJSRuntime), U8(153), R(3), U8(4),
+  /*  140 E> */ B(CallJSRuntime), U8(152), R(3), U8(4),
                 B(Star), R(3),
                 B(Ldar), R(this),
                 B(JumpIfNotHole), U8(4),

test/mjsunit/modules-namespace1.js

@@ -22,8 +22,7 @@ assertTrue(Reflect.setPrototypeOf(foo, null));
 assertFalse(Reflect.setPrototypeOf(foo, {}));
 assertSame(null, Reflect.getPrototypeOf(foo));
 assertEquals(
-    ["bla", "foo_again", "yo", Symbol.toStringTag, Symbol.iterator],
-    Reflect.ownKeys(foo));
+    ["bla", "foo_again", "yo", Symbol.toStringTag], Reflect.ownKeys(foo));
 
 // Its "yo" property.
 assertEquals(
@@ -50,40 +49,6 @@ assertEquals(
     {value: "Module", configurable: true, writable: false, enumerable: false},
     Reflect.getOwnPropertyDescriptor(foo, Symbol.toStringTag));
 
-// Its @@iterator property.
-assertTrue(Reflect.has(foo, Symbol.iterator));
-assertEquals("function", typeof Reflect.get(foo, Symbol.iterator));
-assertEquals("[Symbol.iterator]", foo[Symbol.iterator].name);
-assertEquals(0, foo[Symbol.iterator].length);
-assertSame(Function.prototype, foo[Symbol.iterator].__proto__);
-assertEquals(
-    {value: foo[Symbol.iterator],
-     configurable: true, writable: true, enumerable: false},
-    Reflect.getOwnPropertyDescriptor(foo, Symbol.iterator));
-assertEquals(["bla", "foo_again", "yo"], [...foo]);
-assertThrows(() => (42, foo[Symbol.iterator])(), TypeError);
-{
-  let it = foo[Symbol.iterator]();
-  assertSame(it.__proto__, ([][Symbol.iterator]()).__proto__.__proto__);
-  assertEquals(["next"], Reflect.ownKeys(it));
-  assertEquals(
-      {value: it.next, configurable: true, writable: true, enumerable: false},
-      Reflect.getOwnPropertyDescriptor(it, "next"));
-  assertEquals("function", typeof it.next);
-  assertEquals("next", it.next.name);
-  assertEquals(0, it.next.length);
-  assertSame(Function.prototype, it.next.__proto__);
-  assertFalse(it === foo[Symbol.iterator]());
-  assertFalse(it.next === foo[Symbol.iterator]().next);
-  assertThrows(() => (42, it.next)(), TypeError);
-  assertThrows(() => it.next.call(foo[Symbol.iterator]()), TypeError);
-  let next = it.next;
-  assertEquals(42, (it.next = 42, it.next));
-  assertEquals(43, (it.bla = 43, it.bla));
-  assertTrue(delete it.next);
-  assertThrows(() => next.call(foo[Symbol.iterator]()), TypeError);
-}
-
 // TODO(neis): Clarify spec w.r.t. other symbols.
 
 // Nonexistant properties.

test/mjsunit/modules-namespace2.js

@@ -5,10 +5,8 @@
 // MODULE
 
 assertEquals(
-    ["b", "c", "get_a", "ns2", "set_a", "zzz",
-     Symbol.toStringTag, Symbol.iterator],
+    ["b", "c", "get_a", "ns2", "set_a", "zzz", Symbol.toStringTag],
     Reflect.ownKeys(ns));
-assertEquals(["b", "c", "get_a", "ns2", "set_a", "zzz"], [...ns]);
 
 import * as foo from "modules-skip-1.js";
 assertSame(foo.a, ns.b);

test/test262/test262.status

@@ -450,6 +450,14 @@
   'language/module-code/namespace/internals/set': [FAIL],
   'language/module-code/namespace/internals/define-own-property': [FAIL],
 
+  # Symbol.iterator on namespace objects was removed, tests need to be updated.
+  'language/module-code/namespace/Symbol.iterator/*': [SKIP],
+  'language/module-code/namespace/internals/get-own-property-sym': [SKIP],
+  'language/module-code/namespace/internals/get-sym-found': [SKIP],
+  'language/module-code/namespace/internals/has-property-sym-found': [SKIP],
+  'language/module-code/namespace/internals/own-property-keys-binding-types': [SKIP],
+  'language/module-code/namespace/internals/own-property-keys-sort': [SKIP],
+
 ######################## NEEDS INVESTIGATION ###########################
 
   # These test failures are specific to the intl402 suite and need investigation