| /* |
| * Copyright (c) 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 8080156 8060036 |
| * @summary Test correctness of type propagation to CmpUNodes. |
| * |
| * @run main compiler.types.TestTypePropagationToCmpU |
| */ |
| |
| package compiler.types; |
| |
| public class TestTypePropagationToCmpU { |
| public static void main(String[] args) { |
| try { |
| // Trigger compilation |
| for (int i = 0; i < 100_000; ++i) { |
| test(); |
| } |
| } catch (NullPointerException e) { |
| // Test should never throw a NullPointerException |
| throw new RuntimeException("Test failed"); |
| } |
| } |
| |
| static int global = 42; |
| |
| public static void test() { |
| int a = Integer.MIN_VALUE; |
| int b = global; |
| char[] buf = { 0 }; |
| for (int i = 0; i <= b; ++i) { |
| a = i - b; |
| } |
| // C2 adds a range check and an uncommon trap here to ensure that the array index |
| // is in bounds. If type information is not propagated correctly to the corresponding |
| // CmpUNode, this trap may be always taken. Because C2 also removes the unnecessary |
| // allocation of 'buf', a NullPointerException is thrown in this case. |
| char c = buf[(a * 11) / 2 - a]; // a is 0 here if global >= 0 |
| buf[0] = 0; |
| } |
| } |