Amend DataView, ArrayBuffer, and TypedArray methods to use ToIndex.

src/js/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 27 matching lines @@
 */
 
 
 function ToPositiveInteger(x, rangeErrorIndex) {
   var i = TO_INTEGER(x) + 0;
   if (i < 0) throw MakeRangeError(rangeErrorIndex);
   return i;
 }
 
 
+function ToIndex(x, rangeErrorIndex) {
+  var i = TO_INTEGER(x) + 0;
+  if (i < 0 || i > kMaxSafeInteger) throw MakeRangeError(rangeErrorIndex);

[Dan Ehrenberg, 2016/06/29 19:13:43]

Pass x as an argument here?

[bakkot, 2016/06/29 19:25:09]

The messages passed to this function don't take an argument.

+  return i;
+}
+
+
 function MaxSimple(a, b) {
   return a > b ? a : b;
 }
 
 
 function MinSimple(a, b) {
   return a > b ? b : a;
 }
 
 
@@ skipping 29 matching lines @@
 // boilerplate gets the right prototype.
 %FunctionSetPrototype(GlobalArray, new GlobalArray(0));
 
 // ----------------------------------------------------------------------------
 // Exports
 
 utils.Export(function(to) {
   to.MaxSimple = MaxSimple;
   to.MinSimple = MinSimple;
   to.ToPositiveInteger = ToPositiveInteger;
+  to.ToIndex = ToIndex;
   to.SpeciesConstructor = SpeciesConstructor;
 });
 
 })