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/*
* Copyright (c) 2020, Red Hat, Inc. 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 8239569
* @summary Phi of AddP transformation can cause offset in constant array to be dropped
*
* @run main/othervm -XX:-BackgroundCompilation TestWrongOffsetConstantArrayConstant
*/
public class TestWrongOffsetConstantArrayConstant {
private static volatile char volatileField;
public static void main(String[] args) {
for (int i = 0; i < 20_000; i++) {
if (test('o') != 'o') {
throw new RuntimeException("bad result");
}
}
}
static final byte[] str = {'f', 'o'};
private static char test(char b1) {
// Trigger extra rounds of loop opts
for (int i = 0; i < 3; i++) {
for (int k = 0; k < 3; k++) {
for (int l = 0; l < 3; l++) {
}
}
}
// Will fully unroll
int i = 0;
for (; i < str.length; i++) {
final byte b = str[i]; // LoadB
if (b == b1) {
break;
}
}
// LoadUB that shares address with LoadB above
// Will split thru phi
final char c = (char) (str[i] & 0xff);
volatileField = c;
// LoadUB that shares address with LoadB and LoadUB above
final char c2 = (char) (str[i] & 0xff);
return c2;
}
}
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