| // 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() { |
| class A {} |
| |
| function foo(a, fn) { |
| const C = a.constructor; |
| fn(a); |
| return a instanceof C; |
| }; |
| %PrepareFunctionForOptimization(foo); |
| assertTrue(foo(new A(), a => {})); |
| assertTrue(foo(new A(), a => {})); |
| %OptimizeFunctionOnNextCall(foo); |
| assertTrue(foo(new A(), a => {})); |
| assertFalse(foo(new A(), a => { |
| a.__proto__ = {}; |
| })); |
| })(); |
