[builtins] Support SameValue and SameValueZero via runtime functions.

src/js/v8natives.js

 // 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.
 
 (function(global, utils) {
 
 %CheckIsBootstrapping();
 
 // ----------------------------------------------------------------------------
 // Imports
 
 var GlobalArray = global.Array;
 var GlobalBoolean = global.Boolean;
 var GlobalNumber = global.Number;
 var GlobalObject = global.Object;
 var InternalArray = utils.InternalArray;
 var iteratorSymbol = utils.ImportNow("iterator_symbol");
 var MakeRangeError;
 var MakeSyntaxError;
 var MakeTypeError;
 var MathAbs;
 var NaN = %GetRootNaN();
 var ObjectToString = utils.ImportNow("object_to_string");
 var ObserveBeginPerformSplice;
 var ObserveEndPerformSplice;
 var ObserveEnqueueSpliceRecord;
-var SameValue = utils.ImportNow("SameValue");
 var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
 
 utils.Import(function(from) {
   MakeRangeError = from.MakeRangeError;
   MakeSyntaxError = from.MakeSyntaxError;
   MakeTypeError = from.MakeTypeError;
   MathAbs = from.MathAbs;
   ObserveBeginPerformSplice = from.ObserveBeginPerformSplice;
   ObserveEndPerformSplice = from.ObserveEndPerformSplice;
   ObserveEnqueueSpliceRecord = from.ObserveEnqueueSpliceRecord;
@@ skipping 500 matching lines @@
       throw MakeTypeError(kDefineDisallowed, p);
     } else {
       return false;
     }
   }
 
   if (!IS_UNDEFINED(current)) {
     if ((IsGenericDescriptor(desc) ||
          IsDataDescriptor(desc) == IsDataDescriptor(current)) &&
         (!desc.hasEnumerable() ||
-         SameValue(desc.isEnumerable(), current.isEnumerable())) &&
+         %SameValue(desc.isEnumerable(), current.isEnumerable())) &&
         (!desc.hasConfigurable() ||
-         SameValue(desc.isConfigurable(), current.isConfigurable())) &&
+         %SameValue(desc.isConfigurable(), current.isConfigurable())) &&
         (!desc.hasWritable() ||
-         SameValue(desc.isWritable(), current.isWritable())) &&
+         %SameValue(desc.isWritable(), current.isWritable())) &&
         (!desc.hasValue() ||
-         SameValue(desc.getValue(), current.getValue())) &&
+         %SameValue(desc.getValue(), current.getValue())) &&
         (!desc.hasGetter() ||
-         SameValue(desc.getGet(), current.getGet())) &&
+         %SameValue(desc.getGet(), current.getGet())) &&
         (!desc.hasSetter() ||
-         SameValue(desc.getSet(), current.getSet()))) {
+         %SameValue(desc.getSet(), current.getSet()))) {
       return true;
     }
     if (!current.isConfigurable()) {
       // Step 7
       if (desc.isConfigurable() ||
           (desc.hasEnumerable() &&
            desc.isEnumerable() != current.isEnumerable())) {
         if (should_throw) {
           throw MakeTypeError(kRedefineDisallowed, p);
         } else {
@@ skipping 18 matching lines @@
               if (should_throw) {
                 throw currentIsWritable
                     ? MakeTypeError(kStrongRedefineDisallowed, obj, p)
                     : MakeTypeError(kRedefineDisallowed, p);
               } else {
                 return false;
               }
             }
           }
           if (!currentIsWritable && desc.hasValue() &&
-              !SameValue(desc.getValue(), current.getValue())) {
+              !%SameValue(desc.getValue(), current.getValue())) {
             if (should_throw) {
               throw MakeTypeError(kRedefineDisallowed, p);
             } else {
               return false;
             }
           }
         }
         // Step 11
         if (IsAccessorDescriptor(desc) && IsAccessorDescriptor(current)) {
           if (desc.hasSetter() &&
-              !SameValue(desc.getSet(), current.getSet())) {
+              !%SameValue(desc.getSet(), current.getSet())) {
             if (should_throw) {
               throw MakeTypeError(kRedefineDisallowed, p);
             } else {
               return false;
             }
           }
-          if (desc.hasGetter() && !SameValue(desc.getGet(),current.getGet())) {
+          if (desc.hasGetter() && !%SameValue(desc.getGet(),current.getGet())) {
             if (should_throw) {
               throw MakeTypeError(kRedefineDisallowed, p);
             } else {
               return false;
             }
           }
         }
       }
     }
   }
@@ skipping 233 matching lines @@
   "__lookupGetter__", ObjectLookupGetter,
   "__defineSetter__", ObjectDefineSetter,
   "__lookupSetter__", ObjectLookupSetter
 ]);
 utils.InstallGetterSetter(GlobalObject.prototype, "__proto__", ObjectGetProto,
                     ObjectSetProto);
 
 // Set up non-enumerable functions in the Object object.
 utils.InstallFunctions(GlobalObject, DONT_ENUM, [
   // assign is added in bootstrapper.cc.
   // keys is added in bootstrapper.cc.

[Michael Starzinger, 2016/02/17 09:44:21]

nit: Can we add a comment here saying that "is is added in bootstrapper.cc." as
well?

[Benedikt Meurer, 2016/02/17 10:20:26]

Done.

   "defineProperty", ObjectDefineProperty,
   "defineProperties", ObjectDefineProperties,
   "getPrototypeOf", ObjectGetPrototypeOf,
   "setPrototypeOf", ObjectSetPrototypeOf,
   // getOwnPropertySymbols is added in symbol.js.
-  "is", SameValue,  // ECMA-262, Edition 6, section 19.1.2.10
   // deliverChangeRecords, getNotifier, observe and unobserve are added
   // in object-observe.js.
 ]);
 
 
 // ----------------------------------------------------------------------------
 // Boolean
 
 function BooleanConstructor(x) {
   // TODO(bmeurer): Move this to toplevel.
@@ skipping 275 matching lines @@
   to.ObjectDefineProperties = ObjectDefineProperties;
   to.ObjectDefineProperty = ObjectDefineProperty;
   to.ObjectHasOwnProperty = ObjectHasOwnProperty;
 });
 
 %InstallToContext([
   "object_value_of", ObjectValueOf,
 ]);
 
 })