| /* |
| * Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * @test |
| * @bug 8015499 |
| * @summary javac, Gen is generating extra checkcast instructions in some corner cases |
| * @modules jdk.jdeps/com.sun.tools.classfile |
| * jdk.compiler/com.sun.tools.javac.util |
| * @run main DoubleCastTest |
| */ |
| |
| import java.util.List; |
| import java.util.ArrayList; |
| import com.sun.tools.classfile.*; |
| import com.sun.tools.javac.util.Assert; |
| |
| public class DoubleCastTest { |
| class C { |
| Object x; |
| Object m() { return null; } |
| void m1(byte[] b) {} |
| void m2() { |
| Object o; |
| Object[] os = null; |
| m1((byte[])(o = null)); |
| m1((byte[])o); |
| m1((byte[])(o == null ? o : o)); |
| m1((byte[])m()); |
| m1((byte[])os[0]); |
| m1((byte[])this.x); |
| m1((byte[])((byte []) (o = null))); |
| } |
| } |
| |
| public static void main(String... cmdline) throws Exception { |
| |
| ClassFile cls = ClassFile.read(DoubleCastTest.class.getResourceAsStream("DoubleCastTest$C.class")); |
| for (Method m: cls.methods) |
| check(m); |
| } |
| |
| static void check(Method m) throws Exception { |
| boolean last_is_cast = false; |
| int last_ref = 0; |
| Code_attribute ea = (Code_attribute)m.attributes.get(Attribute.Code); |
| for (Instruction i : ea.getInstructions()) { |
| if (i.getOpcode() == Opcode.CHECKCAST) { |
| Assert.check |
| (!(last_is_cast && last_ref == i.getUnsignedShort(1)), |
| "Double cast found - Test failed"); |
| last_is_cast = true; |
| last_ref = i.getUnsignedShort(1); |
| } else { |
| last_is_cast = false; |
| } |
| } |
| } |
| } |