|  | // Copyright 2019 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 constructor() {} | 
|  | const obj = Object.create(constructor.prototype); | 
|  |  | 
|  | for (let i = 0; i < 1020; ++i) { | 
|  | constructor.prototype["x" + i] = 42; | 
|  | } | 
|  |  | 
|  | function foo() { | 
|  | return obj instanceof constructor; | 
|  | }; | 
|  | %PrepareFunctionForOptimization(foo); | 
|  | assertTrue(foo()); | 
|  | assertTrue(foo()); | 
|  | %OptimizeFunctionOnNextCall(foo); | 
|  | assertTrue(foo()); |