jdk-24/test/hotspot/jtreg/compiler/loopopts/TestNodeSunkFromPreLoop.java
2023-08-30 07:52:05 +00:00

72 lines
2.4 KiB
Java

/*
* Copyright (c) 2023, 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 8314024
* @requires vm.compiler2.enabled
* @summary Node used in check in main loop sunk from pre loop before RC elimination
* @run main/othervm -XX:-BackgroundCompilation -XX:-UseLoopPredicate TestNodeSunkFromPreLoop
*
*/
public class TestNodeSunkFromPreLoop {
private static int unusedField;
public static void main(String[] args) {
A object = new A();
for (int i = 0; i < 20_000; i++) {
test(object, 1000, 0);
}
}
private static int test(A object, int stop, int inv) {
int res = 0;
// pre/main/post loops created for this loop
for (int i = 0; i < stop; i++) {
// Optimized out. Delay transformation of loop above.
for (int j = 0; j < 10; j++) {
for (int k = 0; k < 10; k++) {
}
}
// null check in pre loop so field load also in pre loop
int v = object.field;
int v2 = (v + inv);
if (i > 1000) {
// never taken. v + inv has a use out of loop at an unc.
unusedField = v2;
}
// transformed in the main loop to i + (v + inv)
int v3 = (v + (i + inv));
if (v3 > 1000) {
break;
}
}
return res;
}
private static class A {
public int field;
}
}