1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/test/compiler/intrinsics/stringequals/TestStringEqualsBadLength.java Wed Apr 27 01:25:04 2016 +0800
1.3 @@ -0,0 +1,82 @@
1.4 +/*
1.5 + * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + */
1.26 +
1.27 +/*
1.28 + * @test
1.29 + * @bug 8027445
1.30 + * @summary String.equals() may be called with a length whose upper bits are not cleared
1.31 + * @run main/othervm -XX:-UseOnStackReplacement -XX:-BackgroundCompilation TestStringEqualsBadLength
1.32 + *
1.33 + */
1.34 +
1.35 +import java.util.Arrays;
1.36 +
1.37 +public class TestStringEqualsBadLength {
1.38 +
1.39 + int v1;
1.40 + int v2;
1.41 +
1.42 + boolean m(String s1) {
1.43 + int l = v2 - v1; // 0 - (-1) = 1. On 64 bit: 0xffffffff00000001
1.44 + char[] arr = new char[l];
1.45 + arr[0] = 'a';
1.46 + String s2 = new String(arr);
1.47 + // The string length is not reloaded but the value computed is
1.48 + // reused so pointer computation must not use
1.49 + // 0xffffffff00000001
1.50 + return s2.equals(s1);
1.51 + }
1.52 +
1.53 + // Same thing with String.compareTo()
1.54 + int m2(String s1) {
1.55 + int l = v2 - v1;
1.56 + char[] arr = new char[l+1];
1.57 + arr[0] = 'a';
1.58 + arr[1] = 'b';
1.59 + String s2 = new String(arr);
1.60 + return s2.compareTo(s1);
1.61 + }
1.62 +
1.63 + // Same thing with equals() for arrays
1.64 + boolean m3(char[] arr1) {
1.65 + int l = v2 - v1; // 0 - (-1) = 1. On 64 bit: 0xffffffff00000001
1.66 + char[] arr2 = new char[l];
1.67 + arr2[0] = 'a';
1.68 + return Arrays.equals(arr2, arr1);
1.69 + }
1.70 +
1.71 + static public void main(String[] args) {
1.72 + TestStringEqualsBadLength tse = new TestStringEqualsBadLength();
1.73 + tse.v1 = -1;
1.74 + tse.v2 = 0;
1.75 + char[] arr = new char[1];
1.76 + arr[0] = 'a';
1.77 + for (int i = 0; i < 20000; i++) {
1.78 + tse.m("a");
1.79 + tse.m2("ab");
1.80 + tse.m3(arr);
1.81 + }
1.82 +
1.83 + System.out.println("TEST PASSED");
1.84 + }
1.85 +}
