Revert of [es6] Introduce spec compliant IsConstructor.

src/objects.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_OBJECTS_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 
 #include "src/allocation.h"
@@ skipping 1015 matching lines @@
 
   INLINE(bool IsStruct() const);
 #define DECLARE_STRUCT_PREDICATE(NAME, Name, name) \
   INLINE(bool Is##Name() const);
   STRUCT_LIST(DECLARE_STRUCT_PREDICATE)
 #undef DECLARE_STRUCT_PREDICATE
 
   // ES6, section 7.2.3 IsCallable.
   INLINE(bool IsCallable() const);
 
-  // ES6, section 7.2.4 IsConstructor.
-  INLINE(bool IsConstructor() const);
-
   INLINE(bool IsSpecObject()) const;
   INLINE(bool IsTemplateInfo()) const;
   INLINE(bool IsNameDictionary() const);
   INLINE(bool IsGlobalDictionary() const);
   INLINE(bool IsSeededNumberDictionary() const);
   INLINE(bool IsUnseededNumberDictionary() const);
   INLINE(bool IsOrderedHashSet() const);
   INLINE(bool IsOrderedHashMap() const);
   static bool IsPromise(Handle<Object> object);
 
@@ skipping 4309 matching lines @@
   static const int kRetainingCounterEnd = 0;
 
   // Tells whether the object in the prototype property will be used
   // for instances created from this function.  If the prototype
   // property is set to a value that is not a JSObject, the prototype
   // property will not be used to create instances of the function.
   // See ECMA-262, 13.2.2.
   inline void set_non_instance_prototype(bool value);
   inline bool has_non_instance_prototype();
 
-  // Tells whether the instance has a [[Construct]] internal method.
-  // This property is implemented according to ES6, section 7.2.4.
-  inline void set_is_constructor(bool value);
-  inline bool is_constructor() const;
+  // Tells whether function has special prototype property. If not, prototype
+  // property will not be created when accessed (will return undefined),
+  // and construction from this function will not be allowed.
+  inline void set_function_with_prototype(bool value);
+  inline bool function_with_prototype();
 
   // Tells whether the instance with this map should be ignored by the
   // Object.getPrototypeOf() function and the __proto__ accessor.
   inline void set_is_hidden_prototype();
   inline bool is_hidden_prototype() const;
 
   // Records and queries whether the instance has a named interceptor.
   inline void set_has_named_interceptor();
   inline bool has_named_interceptor();
 
   // Records and queries whether the instance has an indexed interceptor.
   inline void set_has_indexed_interceptor();
   inline bool has_indexed_interceptor();
 
   // Tells whether the instance is undetectable.
   // An undetectable object is a special class of JSObject: 'typeof' operator
   // returns undefined, ToBoolean returns false. Otherwise it behaves like
   // a normal JS object.  It is useful for implementing undetectable
   // document.all in Firefox & Safari.
   // See https://bugzilla.mozilla.org/show_bug.cgi?id=248549.
   inline void set_is_undetectable();
   inline bool is_undetectable();
 
   // Tells whether the instance has a call-as-function handler.
   inline void set_is_observed();
   inline bool is_observed();
 
-  // Tells whether the instance has a [[Call]] internal method.
+  // Tells whether the instance has a [[Call]] internal field.
   // This property is implemented according to ES6, section 7.2.3.
   inline void set_is_callable();
   inline bool is_callable() const;
 
   inline void set_is_strong();
   inline bool is_strong();
   inline void set_is_extensible(bool value);
   inline bool is_extensible();
   inline void set_is_prototype_map(bool value);
   inline bool is_prototype_map() const;
@@ skipping 309 matching lines @@
   // elements_kind that's found in |candidates|, or null handle if no match is
   // found at all.
   static Handle<Map> FindTransitionedMap(Handle<Map> map,
                                          MapHandleList* candidates);
 
   inline bool CanTransition();
 
   inline bool IsPrimitiveMap();
   inline bool IsJSObjectMap();
   inline bool IsJSArrayMap();
-  inline bool IsJSFunctionMap();
   inline bool IsStringMap();
   inline bool IsJSProxyMap();
   inline bool IsJSGlobalProxyMap();
   inline bool IsJSGlobalObjectMap();
   inline bool IsGlobalObjectMap();
 
   inline bool CanOmitMapChecks();
 
   static void AddDependentCode(Handle<Map> map,
                                DependentCode::DependencyGroup group,
@@ skipping 84 matching lines @@
                 Internals::kMapInstanceTypeAndBitFieldOffset);
 
   // Bit positions for bit field.
   static const int kHasNonInstancePrototype = 0;
   static const int kIsCallable = 1;
   static const int kHasNamedInterceptor = 2;
   static const int kHasIndexedInterceptor = 3;
   static const int kIsUndetectable = 4;
   static const int kIsObserved = 5;
   static const int kIsAccessCheckNeeded = 6;
-  static const int kIsConstructor = 7;
+  class FunctionWithPrototype: public BitField<bool, 7,  1> {};
 
   // Bit positions for bit field 2
   static const int kIsExtensible = 0;
   // Bit 1 is free.
   class IsPrototypeMapBits : public BitField<bool, 2, 1> {};
   class ElementsKindBits: public BitField<ElementsKind, 3, 5> {};
 
   // Derived values from bit field 2
   static const int8_t kMaximumBitField2FastElementValue = static_cast<int8_t>(
       (FAST_ELEMENTS + 1) << Map::ElementsKindBits::kShift) - 1;
@@ skipping 1281 matching lines @@
                                    Handle<Object> value);
 
   // Creates a new closure for the fucntion with the same bindings,
   // bound values, and prototype. An equivalent of spec operations
   // ``CloneMethod`` and ``CloneBoundFunction``.
   static Handle<JSFunction> CloneClosure(Handle<JSFunction> function);
 
   // After prototype is removed, it will not be created when accessed, and
   // [[Construct]] from this function will not be allowed.
   bool RemovePrototype();
+  inline bool should_have_prototype();
 
   // Accessor for this function's initial map's [[class]]
   // property. This is primarily used by ECMA native functions.  This
   // method sets the class_name field of this function's initial map
   // to a given value. It creates an initial map if this function does
   // not have one. Note that this method does not copy the initial map
   // if it has one already, but simply replaces it with the new value.
   // Instances created afterwards will have a map whose [[class]] is
   // set to 'value', but there is no guarantees on instances created
   // before.
@@ skipping 3415 matching lines @@
 
   Isolate* isolate_;
   Handle<FixedArray> keys_;
   Handle<OrderedHashSet> set_;
   int length_;
   DISALLOW_COPY_AND_ASSIGN(KeyAccumulator);
 };
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_