jdk/test/hotspot/jtreg/compiler/igvn/TestSplitPhiThroughMergeMem.java
2025-04-15 08:58:02 +00:00

71 lines
2.9 KiB
Java

/*
* Copyright (c) 2025, 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 8351833
* @summary Splitting Phi memory nodes through MergeMem nodes in PhiNode::Ideal
* could sometimes result in a too large number of added nodes within
* a single iteration of the main loop in PhaseIterGVN::optimize. This
* test, reduced from TestScalarReplacementMaxLiveNodes, triggers an
* assert added as part of the fix for the linked bug/issue (the
* assert naturally triggers only before the fix). The test's ability
* to trigger the issue is quite sensitive to the specific String
* constants used. The current set of chosen String constants happened
* to work particularly well.
* @run main/othervm -Xbatch
* -XX:CompileCommand=CompileOnly,compiler.igvn.TestSplitPhiThroughMergeMem::test
* compiler.igvn.TestSplitPhiThroughMergeMem
* @run main compiler.igvn.TestSplitPhiThroughMergeMem
*/
package compiler.igvn;
public class TestSplitPhiThroughMergeMem {
public static void main(String[] args) {
for (int i = 0; i < 10_000; i++) {
int val = i % 50;
test(val == 0, val % 10, val % 20);
}
}
static void test(boolean flag, int param1, int param2) {
if (flag) {
new String("tenth" + param1);
new String("eleventh" + param2);
new String("fifteenth" + param2);
new String("sixteenth" + param1);
new String("seventeenth" + param1);
new String("nineteenth" + param2);
new String("tweenth" + param1);
new String("nineth" + param1);
new String("nineth" + param1);
new String("eighteenth" + param1);
new String("abcdef" + param2);
new String("ghijklmn" + param1);
new String("ghijklmn" + param1);
}
}
}