Ensure slow properties for simple {__proto__:null} literals.

src/ast/ast.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_AST_AST_H_
 #define V8_AST_AST_H_
 
 #include "src/ast/ast-types.h"
 #include "src/ast/ast-value-factory.h"
 #include "src/ast/modules.h"
@@ skipping 1220 matching lines @@
 
   static int parent_num_ids() { return Expression::num_ids(); }
   int local_id(int n) const { return base_id() + parent_num_ids() + n; }
 
   const AstValue* value_;
 };
 
 // Base class for literals that need space in the type feedback vector.
 class MaterializedLiteral : public Expression {
  public:
+  bool is_initialized() const { return 0 < depth_; }
   int depth() const {
-    // only callable after initialization.
-    DCHECK(depth_ >= 1);
+    DCHECK(is_initialized());
     return depth_;
   }
 
   void AssignFeedbackSlots(FeedbackVectorSpec* spec, LanguageMode language_mode,
                            FeedbackSlotCache* cache) {
     literal_slot_ = spec->AddLiteralSlot();
   }
 
   FeedbackSlot literal_slot() const { return literal_slot_; }
 
  private:
   int depth_ : 31;
   FeedbackSlot literal_slot_;
 
   class IsSimpleField
       : public BitField<bool, Expression::kNextBitFieldIndex, 1> {};
 
  protected:
   MaterializedLiteral(int pos, NodeType type)
       : Expression(pos, type), depth_(0) {
     bit_field_ |= IsSimpleField::encode(false);
   }
 
   // A materialized literal is simple if the values consist of only
   // constants and simple object and array literals.
   bool is_simple() const { return IsSimpleField::decode(bit_field_); }
   void set_is_simple(bool is_simple) {
     bit_field_ = IsSimpleField::update(bit_field_, is_simple);
   }
+
   friend class CompileTimeValue;
 
   void set_depth(int depth) {
-    DCHECK_LE(1, depth);
+    DCHECK(!is_initialized());
     depth_ = depth;
   }
 
   // Populate the depth field and any flags the literal has.
   void InitDepthAndFlags();
 
   // Populate the constant properties/elements fixed array.
   void BuildConstants(Isolate* isolate);
   friend class ArrayLiteral;
   friend class ObjectLiteral;
@@ skipping 65 matching lines @@
   bool IsMonomorphic() const { return !receiver_type_.is_null(); }
   Handle<Map> GetReceiverType() const { return receiver_type_; }
 
   bool IsCompileTimeValue() const;
 
   void set_emit_store(bool emit_store);
   bool emit_store() const;
 
   void set_receiver_type(Handle<Map> map) { receiver_type_ = map; }
 
+  bool IsNullPrototype() const {
+    return IsPrototype() && value()->IsNullLiteral();
+  }
+  bool IsPrototype() const { return kind() == PROTOTYPE; }
+
  private:
   friend class AstNodeFactory;
 
   ObjectLiteralProperty(Expression* key, Expression* value, Kind kind,
                         bool is_computed_name);
   ObjectLiteralProperty(AstValueFactory* ast_value_factory, Expression* key,
                         Expression* value, bool is_computed_name);
 
   Kind kind_;
   bool emit_store_;
@@ skipping 17 matching lines @@
   bool may_store_doubles() const {
     return MayStoreDoublesField::decode(bit_field_);
   }
   bool has_elements() const { return HasElementsField::decode(bit_field_); }
   bool has_shallow_properties() const {
     return depth() == 1 && !has_elements() && !may_store_doubles();
   }
   bool has_rest_property() const {
     return HasRestPropertyField::decode(bit_field_);
   }
-
-  // Decide if a property should be in the object boilerplate.
-  static bool IsBoilerplateProperty(Property* property);
+  bool has_null_prototype() const {
+    return HasNullPrototypeField::decode(bit_field_);
+  }
 
   // Populate the depth field and flags.
   void InitDepthAndFlags();
 
   // Get the constant properties fixed array, populating it if necessary.
   Handle<BoilerplateDescription> GetOrBuildConstantProperties(
       Isolate* isolate) {
     if (constant_properties_.is_null()) {
       BuildConstantProperties(isolate);
     }
     return constant_properties();
   }
 
   // Populate the constant properties fixed array.
   void BuildConstantProperties(Isolate* isolate);
 
   // Mark all computed expressions that are bound to a key that
   // is shadowed by a later occurrence of the same key. For the
   // marked expressions, no store code is emitted.
   void CalculateEmitStore(Zone* zone);
 
   // Determines whether the {FastCloneShallowObject} builtin can be used.
   bool IsFastCloningSupported() const;
 
   // Assemble bitfield of flags for the CreateObjectLiteral helper.
   int ComputeFlags(bool disable_mementos = false) const {
     int flags = fast_elements() ? kFastElements : kNoFlags;
-    if (has_shallow_properties()) {
-      flags |= kShallowProperties;
-    }
-    if (disable_mementos) {
-      flags |= kDisableMementos;
-    }
+    if (has_shallow_properties()) flags |= kShallowProperties;
+    if (disable_mementos) flags |= kDisableMementos;
+    if (has_null_prototype()) flags |= kHasNullPrototype;
     return flags;
   }
 
+  int EncodeLiteralType() {
+    int flags = fast_elements() ? kFastElements : kNoFlags;
+    if (has_shallow_properties()) flags |= kShallowProperties;
+    if (has_null_prototype()) flags |= kHasNullPrototype;
+    return flags;
+  }
+
   enum Flags {
     kNoFlags = 0,
     kFastElements = 1,
     kShallowProperties = 1 << 1,
     kDisableMementos = 1 << 2,
-    kHasRestProperty = 1 << 3,
+    kHasNullPrototype = 1 << 3,
   };
 
   struct Accessors: public ZoneObject {
     Accessors() : getter(NULL), setter(NULL), bailout_id(BailoutId::None()) {}
     ObjectLiteralProperty* getter;
     ObjectLiteralProperty* setter;
     BailoutId bailout_id;
   };
 
   BailoutId CreateLiteralId() const { return BailoutId(local_id(0)); }
@@ skipping 15 matching lines @@
 
   ObjectLiteral(ZoneList<Property*>* properties,
                 uint32_t boilerplate_properties, int pos,
                 bool has_rest_property)
       : MaterializedLiteral(pos, kObjectLiteral),
         boilerplate_properties_(boilerplate_properties),
         properties_(properties) {
     bit_field_ |= FastElementsField::encode(false) |
                   HasElementsField::encode(false) |
                   MayStoreDoublesField::encode(false) |
-                  HasRestPropertyField::encode(has_rest_property);
+                  HasRestPropertyField::encode(has_rest_property) |
+                  HasNullPrototypeField::encode(false);
   }
 
   static int parent_num_ids() { return MaterializedLiteral::num_ids(); }
   int local_id(int n) const { return base_id() + parent_num_ids() + n; }
 
+  void InitFlagsForPendingNullPrototype(int i);
+
+  void set_fast_elements(bool fast_elements) {
+    bit_field_ = FastElementsField::update(bit_field_, fast_elements);
+  }
+  void set_has_elements(bool has_elements) {
+    bit_field_ = HasElementsField::update(bit_field_, has_elements);
+  }
+  void set_has_null_protoype(bool has_null_prototype) {
+    bit_field_ = HasNullPrototypeField::update(bit_field_, has_null_prototype);
+  }
+
   uint32_t boilerplate_properties_;
   Handle<BoilerplateDescription> constant_properties_;
   ZoneList<Property*>* properties_;
 
   class FastElementsField
       : public BitField<bool, MaterializedLiteral::kNextBitFieldIndex, 1> {};
   class HasElementsField : public BitField<bool, FastElementsField::kNext, 1> {
   };
   class MayStoreDoublesField
       : public BitField<bool, HasElementsField::kNext, 1> {};
   class HasRestPropertyField
       : public BitField<bool, MayStoreDoublesField::kNext, 1> {};
+  class HasNullPrototypeField
+      : public BitField<bool, HasRestPropertyField::kNext, 1> {};
 };
 
 
 // A map from property names to getter/setter pairs allocated in the zone.
 class AccessorTable
     : public base::TemplateHashMap<Literal, ObjectLiteral::Accessors,
                                    bool (*)(void*, void*),
                                    ZoneAllocationPolicy> {
  public:
   explicit AccessorTable(Zone* zone)
@@ skipping 68 matching lines @@
 
   // Populate the constant elements fixed array.
   void BuildConstantElements(Isolate* isolate);
 
   // Determines whether the {FastCloneShallowArray} builtin can be used.
   bool IsFastCloningSupported() const;
 
   // Assemble bitfield of flags for the CreateArrayLiteral helper.
   int ComputeFlags(bool disable_mementos = false) const {
     int flags = depth() == 1 ? kShallowElements : kNoFlags;
-    if (disable_mementos) {
-      flags |= kDisableMementos;
-    }
+    if (disable_mementos) flags |= kDisableMementos;
     return flags;
   }
 
   // Provide a mechanism for iterating through values to rewrite spreads.
   ZoneList<Expression*>::iterator FirstSpread() const {
     return (first_spread_index_ >= 0) ? values_->begin() + first_spread_index_
                                       : values_->end();
   }
   ZoneList<Expression*>::iterator EndValue() const { return values_->end(); }
 
@@ skipping 2113 matching lines @@
                                     : NULL;                                   \
   }
 AST_NODE_LIST(DECLARE_NODE_FUNCTIONS)
 #undef DECLARE_NODE_FUNCTIONS
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_AST_AST_H_