diff --git a/src/hotspot/share/opto/loopopts.cpp b/src/hotspot/share/opto/loopopts.cpp index e74e088c5ef93..89b723bf92c73 100644 --- a/src/hotspot/share/opto/loopopts.cpp +++ b/src/hotspot/share/opto/loopopts.cpp @@ -1642,7 +1642,7 @@ void PhaseIdealLoop::try_sink_out_of_loop(Node* n) { // Find control for 'x' next to use but not inside inner loops. x_ctrl = place_outside_loop(x_ctrl, n_loop); // Replace all uses - if (u->is_ConstraintCast() && u->bottom_type()->higher_equal(_igvn.type(n)) && u->in(0) == x_ctrl) { + if (u->is_ConstraintCast() && _igvn.type(n)->higher_equal(u->bottom_type()) && u->in(0) == x_ctrl) { // If we're sinking a chain of data nodes, we might have inserted a cast to pin the use which is not necessary // anymore now that we're going to pin n as well _igvn.replace_node(u, x); diff --git a/test/hotspot/jtreg/gc/shenandoah/compiler/TestSinkingNodeDropsNotNullCast.java b/test/hotspot/jtreg/gc/shenandoah/compiler/TestSinkingNodeDropsNotNullCast.java new file mode 100644 index 0000000000000..4987f448aa5d1 --- /dev/null +++ b/test/hotspot/jtreg/gc/shenandoah/compiler/TestSinkingNodeDropsNotNullCast.java @@ -0,0 +1,68 @@ +/* + * 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 8313262 + * @summary Sinking node may cause required cast to be dropped + * @requires vm.gc.Shenandoah + * @run main/othervm -XX:-BackgroundCompilation -XX:+UseShenandoahGC TestSinkingNodeDropsNotNullCast + */ + +import java.util.Arrays; + +public class TestSinkingNodeDropsNotNullCast { + public static void main(String[] args) { + Object[] array1 = new Object[100]; + Object[] array2 = new Object[100]; + Arrays.fill(array2, new Object()); + for (int i = 0; i < 20_000; i++) { + test(array1); + test(array1); + test(array2); + } + } + + private static Object test(Object[] array) { + Object o; + int i = 1; + do { + synchronized (new Object()) { + } + o = array[i]; + if (o != null) { + if (o instanceof A) { + return ((A) o).field; + } else { + return o; + } + } + i++; + } while (i < 100); + return o; + } + + private static class A { + Object field; + } +}