|  | // 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 o = {v:1}; | 
|  | var deopt = false; | 
|  |  | 
|  | Object.defineProperty(o, "x", { | 
|  | get: function() { return this.v; }, | 
|  | set: function(v) { | 
|  | this.v = v; | 
|  | if (deopt) { | 
|  | %DeoptimizeFunction(foo); | 
|  | } | 
|  | } | 
|  | }); | 
|  |  | 
|  | function foo(o) { | 
|  | return o.x++; | 
|  | } | 
|  |  | 
|  | %PrepareFunctionForOptimization(foo); | 
|  | assertEquals(1, foo(o)); | 
|  | assertEquals(2, foo(o)); | 
|  | %OptimizeFunctionOnNextCall(foo); | 
|  | deopt = true; | 
|  | assertEquals(3, foo(o)); |