Use a kMaxSafeInteger instead of Number.MAX_SAFE_INTEGER

src/runtime.js

 // Copyright 2006-2008 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.
 
 // This files contains runtime support implemented in JavaScript.
 
 // CAUTION: Some of the functions specified in this file are called
 // directly from compiled code. These are the functions with names in
 // ALL CAPS. The compiled code passes the first argument in 'this'.
 
@@ skipping 15 matching lines @@
 
 var harmony_tolength = false;
 
 (function(global, utils) {
 
 %CheckIsBootstrapping();
 
 var GlobalArray = global.Array;
 var GlobalBoolean = global.Boolean;
 var GlobalString = global.String;
 var GlobalNumber = global.Number;

[adamk, 2015/09/17 21:07:08]

I don't think you need this import anymore.

[aperez, 2015/09/17 23:33:08]

Acknowledged.

 var isConcatSpreadableSymbol =
     utils.ImportNow("is_concat_spreadable_symbol");
 
 // ----------------------------------------------------------------------------
 
 /* -----------------------------------
 - - -   C o m p a r i s o n   - - -
 -----------------------------------
 */
 
@@ skipping 248 matching lines @@
 function ToInteger(x) {
   if (%_IsSmi(x)) return x;
   return %NumberToInteger(ToNumber(x));
 }
 
 
 // ES6, draft 08-24-14, section 7.1.15
 function ToLength(arg) {
   arg = ToInteger(arg);
   if (arg < 0) return 0;
-  return arg < GlobalNumber.MAX_SAFE_INTEGER ? arg
-                                             : GlobalNumber.MAX_SAFE_INTEGER;
+  return arg < kMaxSafeInteger ? arg : kMaxSafeInteger;
 }
 
 
 // ES5, section 9.12
 function SameValue(x, y) {
   if (typeof x != typeof y) return false;
   if (IS_NUMBER(x)) {
     if (NUMBER_IS_NAN(x) && NUMBER_IS_NAN(y)) return true;
     // x is +0 and y is -0 or vice versa.
     if (x === 0 && y === 0 && %_IsMinusZero(x) != %_IsMinusZero(y)) {
@@ skipping 138 matching lines @@
 
 utils.Export(function(to) {
   to.ToBoolean = ToBoolean;
   to.ToLength = ToLength;
   to.ToNumber = ToNumber;
   to.ToPrimitive = ToPrimitive;
   to.ToString = ToString;
 });
 
 })