// Copyright 2015 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 Migrator(o) { return o.foo; }; %PrepareFunctionForOptimization(Migrator); function Loader(o) { return o[0]; }; %PrepareFunctionForOptimization(Loader); var first_smi_array = [1]; var second_smi_array = [2]; var first_object_array = ["first"]; var second_object_array = ["string"]; assertTrue(%HasSmiElements(first_smi_array)); assertTrue(%HasSmiElements(second_smi_array)); assertTrue(%HasObjectElements(first_object_array)); assertTrue(%HasObjectElements(second_object_array)); // Prepare identical transition chains for smi and object arrays. first_smi_array.foo = 0; second_smi_array.foo = 0; first_object_array.foo = 0; second_object_array.foo = 0; // Collect type feedback for not-yet-deprecated original object array map. for (var i = 0; i < 3; i++) Migrator(second_object_array); // Blaze a migration trail for smi array maps. // This marks the migrated smi array map as a migration target. first_smi_array.foo = 0.5; print(second_smi_array.foo); // Deprecate original object array map. // Use TryMigrate from deferred optimized code to migrate second object array. first_object_array.foo = 0.5; %OptimizeFunctionOnNextCall(Migrator); Migrator(second_object_array); // |second_object_array| now erroneously has a smi map. // Optimized code assuming smi elements will expose this. for (var i = 0; i < 3; i++) Loader(second_smi_array); %OptimizeFunctionOnNextCall(Loader); assertEquals("string", Loader(second_object_array)); // Any of the following checks will also fail: assertTrue(%HasObjectElements(second_object_array)); assertFalse(%HasSmiElements(second_object_array)); assertTrue(%HaveSameMap(first_object_array, second_object_array)); assertFalse(%HaveSameMap(first_smi_array, second_object_array)); %ClearFunctionFeedback(Loader); %ClearFunctionFeedback(Migrator);