// Copyright 2016 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 var Foo = { [Symbol.hasInstance]: Function.prototype[Symbol.hasInstance] }; // TurboFan will optimize this to false via constant-folding the // OrdinaryHasInstance call inside Function.prototype[@@hasInstance]. function foo() { return 1 instanceof Foo; } %PrepareFunctionForOptimization(foo); assertEquals(false, foo()); assertEquals(false, foo()); %OptimizeFunctionOnNextCall(foo); assertEquals(false, foo());