[compiler] Support Object.create(null) inlining in TF

In the ideal case, this will speed up Object.create(null) by ~10x.

Drive-by-fix: Spread usage of new IsSpecialReceiverMap() and
              IsSpecialReceiverInstanceType(InstanceType) helpers.

BUG=v8:5788

Review-Url: https://codereview.chromium.org/2622723003
Cr-Commit-Position: refs/heads/master@{#42321}

src/compiler/access-builder.cc

@@ -843,6 +843,68 @@ ElementAccess AccessBuilder::ForTypedArrayElement(ExternalArrayType type,
   return access;
 }
 
+// static
+FieldAccess AccessBuilder::ForHashTableBaseNumberOfElements() {
+  FieldAccess access = {
+      kTaggedBase,
+      FixedArray::OffsetOfElementAt(HashTableBase::kNumberOfElementsIndex),
+      MaybeHandle<Name>(),
+      MaybeHandle<Map>(),
+      Type::SignedSmall(),
+      MachineType::TaggedSigned(),
+      kNoWriteBarrier};
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForHashTableBaseNumberOfDeletedElement() {
+  FieldAccess access = {
+      kTaggedBase, FixedArray::OffsetOfElementAt(
+                       HashTableBase::kNumberOfDeletedElementsIndex),
+      MaybeHandle<Name>(), MaybeHandle<Map>(), Type::SignedSmall(),
+      MachineType::TaggedSigned(), kNoWriteBarrier};
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForHashTableBaseCapacity() {
+  FieldAccess access = {
+      kTaggedBase,
+      FixedArray::OffsetOfElementAt(HashTableBase::kCapacityIndex),
+      MaybeHandle<Name>(),
+      MaybeHandle<Map>(),
+      Type::SignedSmall(),
+      MachineType::TaggedSigned(),
+      kNoWriteBarrier};
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForDictionaryMaxNumberKey() {
+  FieldAccess access = {
+      kTaggedBase,
+      FixedArray::OffsetOfElementAt(NameDictionary::kMaxNumberKeyIndex),
+      MaybeHandle<Name>(),
+      MaybeHandle<Map>(),
+      Type::Any(),
+      MachineType::AnyTagged(),
+      kNoWriteBarrier};
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForNextEnumerationIndex() {
+  FieldAccess access = {
+      kTaggedBase,
+      FixedArray::OffsetOfElementAt(NameDictionary::kNextEnumerationIndexIndex),
+      MaybeHandle<Name>(),
+      MaybeHandle<Map>(),
+      Type::SignedSmall(),
+      MachineType::TaggedSigned(),
+      kNoWriteBarrier};
+  return access;
+}
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8

src/compiler/access-builder.h

@@ -241,6 +241,15 @@ class V8_EXPORT_PRIVATE AccessBuilder final
   static ElementAccess ForTypedArrayElement(ExternalArrayType type,
                                             bool is_external);
 
+  // Provides access to HashTable fields.
+  static FieldAccess ForHashTableBaseNumberOfElements();
+  static FieldAccess ForHashTableBaseNumberOfDeletedElement();
+  static FieldAccess ForHashTableBaseCapacity();
+
+  // Provides access to Dictionary fields.
+  static FieldAccess ForDictionaryMaxNumberKey();
+  static FieldAccess ForNextEnumerationIndex();
+
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(AccessBuilder);
 };

src/compiler/js-builtin-reducer.cc

@@ -4,6 +4,7 @@
 
 #include "src/compiler/js-builtin-reducer.h"
 
+#include "src/base/bits.h"
 #include "src/compilation-dependencies.h"
 #include "src/compiler/access-builder.h"
 #include "src/compiler/js-graph.h"
@@ -1485,6 +1486,99 @@ Reduction JSBuiltinReducer::ReduceNumberParseInt(Node* node) {
   return NoChange();
 }
 
+// ES6 section #sec-object.create Object.create(proto, properties)
+Reduction JSBuiltinReducer::ReduceObjectCreate(Node* node) {
+  // We need exactly target, receiver and value parameters.
+  int arg_count = node->op()->ValueInputCount();
+  if (arg_count != 3) return NoChange();
+  Node* effect = NodeProperties::GetEffectInput(node);
+  Node* control = NodeProperties::GetControlInput(node);
+  Node* prototype = NodeProperties::GetValueInput(node, 2);
+  Type* prototype_type = NodeProperties::GetType(prototype);
+  Handle<Map> instance_map;
+  if (!prototype_type->IsHeapConstant()) return NoChange();
+  Handle<HeapObject> prototype_const =
+      prototype_type->AsHeapConstant()->Value();
+  if (!prototype_const->IsNull(isolate()) && !prototype_const->IsJSReceiver()) {
+    return NoChange();
+  }
+  instance_map = Map::GetObjectCreateMap(prototype_const);
+  Node* properties = jsgraph()->EmptyFixedArrayConstant();
+  if (instance_map->is_dictionary_map()) {
+    // Allocated an empty NameDictionary as backing store for the properties.
+    Handle<Map> map(isolate()->heap()->hash_table_map(), isolate());
+    int capacity =
+        NameDictionary::ComputeCapacity(NameDictionary::kInitialCapacity);
+    DCHECK(base::bits::IsPowerOfTwo32(capacity));
+    int length = NameDictionary::EntryToIndex(capacity);
+    int size = NameDictionary::SizeFor(length);
+
+    effect = graph()->NewNode(
+        common()->BeginRegion(RegionObservability::kNotObservable), effect);
+
+    Node* value = effect =
+        graph()->NewNode(simplified()->Allocate(NOT_TENURED),
+                         jsgraph()->Constant(size), effect, control);
+    effect =
+        graph()->NewNode(simplified()->StoreField(AccessBuilder::ForMap()),
+                         value, jsgraph()->HeapConstant(map), effect, control);
+
+    // Initialize FixedArray fields.
+    effect = graph()->NewNode(
+        simplified()->StoreField(AccessBuilder::ForFixedArrayLength()), value,
+        jsgraph()->SmiConstant(length), effect, control);
+    // Initialize HashTable fields.
+    effect =
+        graph()->NewNode(simplified()->StoreField(
+                             AccessBuilder::ForHashTableBaseNumberOfElements()),
+                         value, jsgraph()->SmiConstant(0), effect, control);
+    effect = graph()->NewNode(
+        simplified()->StoreField(
+            AccessBuilder::ForHashTableBaseNumberOfDeletedElement()),
+        value, jsgraph()->SmiConstant(0), effect, control);
+    effect = graph()->NewNode(
+        simplified()->StoreField(AccessBuilder::ForHashTableBaseCapacity()),
+        value, jsgraph()->SmiConstant(capacity), effect, control);
+    // Initialize Dictionary fields.
+    effect = graph()->NewNode(
+        simplified()->StoreField(AccessBuilder::ForDictionaryMaxNumberKey()),
+        value, jsgraph()->UndefinedConstant(), effect, control);
+    effect = graph()->NewNode(
+        simplified()->StoreField(AccessBuilder::ForNextEnumerationIndex()),
+        value, jsgraph()->SmiConstant(PropertyDetails::kInitialIndex), effect,
+        control);
+
+    properties = effect =
+        graph()->NewNode(common()->FinishRegion(), value, effect);
+  }
+
+  int const instance_size = instance_map->instance_size();
+  dependencies()->AssumeInitialMapCantChange(instance_map);
+
+  // Emit code to allocate the JSObject instance for the given
+  // {instance_map}.
+  effect = graph()->NewNode(
+      common()->BeginRegion(RegionObservability::kNotObservable), effect);
+  Node* value = effect =
+      graph()->NewNode(simplified()->Allocate(NOT_TENURED),
+                       jsgraph()->Constant(instance_size), effect, control);
+  effect =
+      graph()->NewNode(simplified()->StoreField(AccessBuilder::ForMap()), value,
+                       jsgraph()->HeapConstant(instance_map), effect, control);
+  effect = graph()->NewNode(
+      simplified()->StoreField(AccessBuilder::ForJSObjectProperties()), value,
+      properties, effect, control);
+  effect = graph()->NewNode(
+      simplified()->StoreField(AccessBuilder::ForJSObjectElements()), value,
+      jsgraph()->EmptyFixedArrayConstant(), effect, control);
+
+  value = effect = graph()->NewNode(common()->FinishRegion(), value, effect);
+
+  // replace it
+  ReplaceWithValue(node, value, effect, control);
+  return Replace(value);
+}
+
 // ES6 section 21.1.2.1 String.fromCharCode ( ...codeUnits )
 Reduction JSBuiltinReducer::ReduceStringFromCharCode(Node* node) {
   JSCallReduction r(node);
@@ -1990,6 +2084,9 @@ Reduction JSBuiltinReducer::Reduce(Node* node) {
     case kNumberParseInt:
       reduction = ReduceNumberParseInt(node);
       break;
+    case kObjectCreate:
+      reduction = ReduceObjectCreate(node);
+      break;
     case kStringFromCharCode:
       reduction = ReduceStringFromCharCode(node);
       break;

src/compiler/js-builtin-reducer.h

@@ -99,6 +99,7 @@ class V8_EXPORT_PRIVATE JSBuiltinReducer final
   Reduction ReduceNumberIsNaN(Node* node);
   Reduction ReduceNumberIsSafeInteger(Node* node);
   Reduction ReduceNumberParseInt(Node* node);
+  Reduction ReduceObjectCreate(Node* node);
   Reduction ReduceStringCharAt(Node* node);
   Reduction ReduceStringCharCodeAt(Node* node);
   Reduction ReduceStringFromCharCode(Node* node);

src/lookup.cc

@@ -73,7 +73,7 @@ void LookupIterator::Next() {
   JSReceiver* holder = *holder_;
   Map* map = holder->map();
 
-  if (map->instance_type() <= LAST_SPECIAL_RECEIVER_TYPE) {
+  if (map->IsSpecialReceiverMap()) {
     state_ = IsElement() ? LookupInSpecialHolder<true>(map, holder)
                          : LookupInSpecialHolder<false>(map, holder);
     if (IsFound()) return;

src/lookup.h

@@ -288,7 +288,7 @@ class V8_EXPORT_PRIVATE LookupIterator final BASE_EMBEDDED {
   void NextInternal(Map* map, JSReceiver* holder);
   template <bool is_element>
   inline State LookupInHolder(Map* map, JSReceiver* holder) {
-    return map->instance_type() <= LAST_SPECIAL_RECEIVER_TYPE
+    return map->IsSpecialReceiverMap()
                ? LookupInSpecialHolder<is_element>(map, holder)
                : LookupInRegularHolder<is_element>(map, holder);
   }

src/objects-inl.h

@@ -2219,6 +2219,9 @@ int JSObject::GetHeaderSize(InstanceType type) {
   }
 }
 
+inline bool IsSpecialReceiverInstanceType(InstanceType instance_type) {
+  return instance_type <= LAST_SPECIAL_RECEIVER_TYPE;
+}
 
 int JSObject::GetInternalFieldCount(Map* map) {
   int instance_size = map->instance_size();
@@ -4946,6 +4949,12 @@ bool Map::IsJSGlobalObjectMap() {
 bool Map::IsJSTypedArrayMap() { return instance_type() == JS_TYPED_ARRAY_TYPE; }
 bool Map::IsJSDataViewMap() { return instance_type() == JS_DATA_VIEW_TYPE; }
 
+bool Map::IsSpecialReceiverMap() {
+  bool result = IsSpecialReceiverInstanceType(instance_type());
+  DCHECK_IMPLIES(!result,
+                 !has_named_interceptor() && !is_access_check_needed());
+  return result;
+}
 
 bool Map::CanOmitMapChecks() {
   return is_stable() && FLAG_omit_map_checks_for_leaf_maps;

src/objects.cc

@@ -4724,6 +4724,36 @@ void Map::EnsureDescriptorSlack(Handle<Map> map, int slack) {
   map->UpdateDescriptors(*new_descriptors, layout_descriptor);
 }
 
+// static
+Handle<Map> Map::GetObjectCreateMap(Handle<HeapObject> prototype) {
+  Isolate* isolate = prototype->GetIsolate();
+  Handle<Map> map(isolate->native_context()->object_function()->initial_map(),
+                  isolate);
+  if (map->prototype() == *prototype) return map;
+  if (prototype->IsNull(isolate)) {
+    return isolate->slow_object_with_null_prototype_map();
+  }
+  if (prototype->IsJSObject()) {
+    Handle<JSObject> js_prototype = Handle<JSObject>::cast(prototype);
+    if (!js_prototype->map()->is_prototype_map()) {
+      JSObject::OptimizeAsPrototype(js_prototype, FAST_PROTOTYPE);
+    }
+    Handle<PrototypeInfo> info =
+        Map::GetOrCreatePrototypeInfo(js_prototype, isolate);
+    // TODO(verwaest): Use inobject slack tracking for this map.
+    if (info->HasObjectCreateMap()) {
+      map = handle(info->ObjectCreateMap(), isolate);
+    } else {
+      map = Map::CopyInitialMap(map);
+      Map::SetPrototype(map, prototype, FAST_PROTOTYPE);
+      PrototypeInfo::SetObjectCreateMap(info, map);
+    }
+    return map;
+  }
+
+  return Map::TransitionToPrototype(map, prototype, REGULAR_PROTOTYPE);
+}
+
 template <class T>
 static int AppendUniqueCallbacks(Handle<TemplateList> callbacks,
                                  Handle<typename T::Array> array,
@@ -8226,8 +8256,8 @@ bool Map::OnlyHasSimpleProperties() {
   // Wrapped string elements aren't explicitly stored in the elements backing
   // store, but are loaded indirectly from the underlying string.
   return !IsStringWrapperElementsKind(elements_kind()) &&
-         instance_type() > LAST_SPECIAL_RECEIVER_TYPE &&
-         !has_hidden_prototype() && !is_dictionary_map();
+         !IsSpecialReceiverMap() && !has_hidden_prototype() &&
+         !is_dictionary_map();
 }
 
 MUST_USE_RESULT Maybe<bool> FastGetOwnValuesOrEntries(

src/objects.h

@@ -6287,6 +6287,8 @@ class Map: public HeapObject {
 
   Code* LookupInCodeCache(Name* name, Code::Flags code);
 
+  static Handle<Map> GetObjectCreateMap(Handle<HeapObject> prototype);
+
   // Computes a hash value for this map, to be used in HashTables and such.
   int Hash();
 
@@ -6311,6 +6313,8 @@ class Map: public HeapObject {
   inline bool IsJSTypedArrayMap();
   inline bool IsJSDataViewMap();
 
+  inline bool IsSpecialReceiverMap();
+
   inline bool CanOmitMapChecks();
 
   static void AddDependentCode(Handle<Map> map,
@@ -7094,7 +7098,8 @@ class Script: public Struct {
   V(Number, isSafeInteger, NumberIsSafeInteger)             \
   V(Number, parseFloat, NumberParseFloat)                   \
   V(Number, parseInt, NumberParseInt)                       \
-  V(Number.prototype, toString, NumberToString)
+  V(Number.prototype, toString, NumberToString)             \
+  V(Object, create, ObjectCreate)
 
 #define ATOMIC_FUNCTIONS_WITH_ID_LIST(V) \
   V(Atomics, load, AtomicsLoad)          \

src/runtime/runtime-array.cc

@@ -496,8 +496,7 @@ RUNTIME_FUNCTION(Runtime_ArrayIncludes_Slow) {
 
   // If the receiver is not a special receiver type, and the length is a valid
   // element index, perform fast operation tailored to specific ElementsKinds.
-  if (object->map()->instance_type() > LAST_SPECIAL_RECEIVER_TYPE &&
-      len < kMaxUInt32 &&
+  if (!object->map()->IsSpecialReceiverMap() && len < kMaxUInt32 &&
       JSObject::PrototypeHasNoElements(isolate, JSObject::cast(*object))) {
     Handle<JSObject> obj = Handle<JSObject>::cast(object);
     ElementsAccessor* elements = obj->GetElementsAccessor();
@@ -595,8 +594,7 @@ RUNTIME_FUNCTION(Runtime_ArrayIndexOf) {
 
   // If the receiver is not a special receiver type, and the length is a valid
   // element index, perform fast operation tailored to specific ElementsKinds.
-  if (object->map()->instance_type() > LAST_SPECIAL_RECEIVER_TYPE &&
-      len < kMaxUInt32 &&
+  if (!object->map()->IsSpecialReceiverMap() && len < kMaxUInt32 &&
       JSObject::PrototypeHasNoElements(isolate, JSObject::cast(*object))) {
     Handle<JSObject> obj = Handle<JSObject>::cast(object);
     ElementsAccessor* elements = obj->GetElementsAccessor();

src/runtime/runtime-object.cc

@@ -222,30 +222,8 @@ RUNTIME_FUNCTION(Runtime_ObjectCreate) {
   // function's initial map from the current native context.
   // TODO(bmeurer): Use a dedicated cache for Object.create; think about
   // slack tracking for Object.create.
-  Handle<Map> map(isolate->native_context()->object_function()->initial_map(),
-                  isolate);
-  if (map->prototype() != *prototype) {
-    if (prototype->IsNull(isolate)) {
-      map = isolate->slow_object_with_null_prototype_map();
-    } else if (prototype->IsJSObject()) {
-      Handle<JSObject> js_prototype = Handle<JSObject>::cast(prototype);
-      if (!js_prototype->map()->is_prototype_map()) {
-        JSObject::OptimizeAsPrototype(js_prototype, FAST_PROTOTYPE);
-      }
-      Handle<PrototypeInfo> info =
-          Map::GetOrCreatePrototypeInfo(js_prototype, isolate);
-      // TODO(verwaest): Use inobject slack tracking for this map.
-      if (info->HasObjectCreateMap()) {
-        map = handle(info->ObjectCreateMap(), isolate);
-      } else {
-        map = Map::CopyInitialMap(map);
-        Map::SetPrototype(map, prototype, FAST_PROTOTYPE);
-        PrototypeInfo::SetObjectCreateMap(info, map);
-      }
-    } else {
-      map = Map::TransitionToPrototype(map, prototype, REGULAR_PROTOTYPE);
-    }
-  }
+  Handle<Map> map =
+      Map::GetObjectCreateMap(Handle<HeapObject>::cast(prototype));
 
   bool is_dictionary_map = map->is_dictionary_map();
   Handle<FixedArray> object_properties;

src/value-serializer.cc

@@ -401,7 +401,7 @@ Maybe<bool> ValueSerializer::WriteJSReceiver(Handle<JSReceiver> receiver) {
 
   // Eliminate callable and exotic objects, which should not be serialized.
   InstanceType instance_type = receiver->map()->instance_type();
-  if (receiver->IsCallable() || (instance_type <= LAST_SPECIAL_RECEIVER_TYPE &&
+  if (receiver->IsCallable() || (IsSpecialReceiverInstanceType(instance_type) &&
                                  instance_type != JS_SPECIAL_API_OBJECT_TYPE)) {
     ThrowDataCloneError(MessageTemplate::kDataCloneError, receiver);
     return Nothing<bool>();