| // Copyright 2017 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. | 
 |  | 
 | // Flags: --allow-natives-syntax | 
 |  | 
 | (function() { | 
 |   function foo(x) { return Number.isNaN(x); } | 
 |  | 
 |   %PrepareFunctionForOptimization(foo); | 
 |   assertTrue(foo(+undefined)); | 
 |   assertFalse(foo(undefined)); | 
 |   %OptimizeFunctionOnNextCall(foo); | 
 |   assertTrue(foo(+undefined)); | 
 |   assertFalse(foo(undefined)); | 
 | })(); | 
 |  | 
 | (function() { | 
 |   function foo(x) { return Number.isNaN(+x); } | 
 |  | 
 |   %PrepareFunctionForOptimization(foo); | 
 |   assertTrue(foo(+undefined)); | 
 |   assertFalse(foo(0)); | 
 |   %OptimizeFunctionOnNextCall(foo); | 
 |   assertTrue(foo(+undefined)); | 
 |   assertFalse(foo(0)); | 
 | })(); | 
 |  | 
 | (function() { | 
 |   function foo(x) { return Number.isNaN(x|0); } | 
 |  | 
 |   %PrepareFunctionForOptimization(foo); | 
 |   assertFalse(foo(+undefined)); | 
 |   assertFalse(foo(0)); | 
 |   %OptimizeFunctionOnNextCall(foo); | 
 |   assertFalse(foo(+undefined)); | 
 |   assertFalse(foo(0)); | 
 | })(); | 
 |  | 
 | (function() { | 
 |   function foo(x) { return Number.isNaN("" + x); } | 
 |  | 
 |   %PrepareFunctionForOptimization(foo); | 
 |   assertFalse(foo(undefined)); | 
 |   assertFalse(foo(0)); | 
 |   %OptimizeFunctionOnNextCall(foo); | 
 |   assertFalse(foo(undefined)); | 
 |   assertFalse(foo(0)); | 
 | })(); | 
 |  | 
 | (function() { | 
 |   function foo(x) { return Number.isNaN(0/0); } | 
 |  | 
 |   %PrepareFunctionForOptimization(foo); | 
 |   assertTrue(foo()); | 
 |   assertTrue(foo()); | 
 |   %OptimizeFunctionOnNextCall(foo); | 
 |   assertTrue(foo()); | 
 |   assertTrue(foo()); | 
 | })(); |