1 /* 2 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /** 25 * JDK-8136544: Call site switching to megamorphic causes incorrect property read 26 * 27 * @test 28 * @option --unstable-relink-threshold=8 29 * @run 30 */ 31 32 var ScriptContext = Java.type("javax.script.ScriptContext"); 33 var ScriptEngineManager = Java.type("javax.script.ScriptEngineManager"); 34 var m = new ScriptEngineManager(); 35 var e = m.getEngineByName("nashorn"); 36 37 var scope = e.getBindings(ScriptContext.ENGINE_SCOPE); 38 var MYVAR = "myvar"; 39 40 function loopupVar() { 41 try { 42 e.eval(MYVAR); 43 return true; 44 } catch (e) { 45 return false; 46 } 47 } 48 49 // make sure we exercise callsite beyond megamorphic threshold we set 50 // in this test via nashorn.unstable.relink.threshold property 51 // In each iteration, callsite is exercised twice (two evals) 52 // So, LIMIT should be more than 4 to exercise megamorphic callsites. 53 54 var LIMIT = 5; // This LIMIT should be more than 4 55 56 for (var i = 0; i < LIMIT; i++) { 57 // remove the variable and lookup 58 delete scope[MYVAR]; 59 Assert.assertFalse(loopupVar(), "Expected true in iteration " + i); 60 61 // set that variable and check again 62 scope[MYVAR] = "foo"; 63 Assert.assertTrue(loopupVar(), "Expected false in iteration " + i); 64 }