| // 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 |
| |
| // A function with a for-in loop, that will be optimized. |
| function foo(o) { |
| for (var i in o) { |
| return o[i]; |
| } |
| } |
| |
| var o = { x: 0.5 }; |
| |
| // Warm up foo with Double values in the enum cache. |
| %PrepareFunctionForOptimization(foo); |
| assertEquals(foo(o), 0.5); |
| assertEquals(foo(o), 0.5); |
| %OptimizeFunctionOnNextCall(foo); |
| assertEquals(foo(o), 0.5); |
| |
| // Transition the double field to a tagged field |
| o.x = "abc"; |
| |
| // Make sure that the optimized code correctly loads the tagged field. |
| assertEquals(foo(o), "abc"); |