8253566: clazz.isAssignableFrom will return false for interface implementors

Reviewed-by: kvn, thartmann, neliasso
This commit is contained in:
Roland Westrelin 2020-10-08 09:33:42 +00:00
parent 66f27b5fca
commit f86037207c
2 changed files with 71 additions and 1 deletions
src/hotspot/share/opto
test/hotspot/jtreg/compiler/types

@ -818,8 +818,10 @@ bool RegionNode::optimize_trichotomy(PhaseIterGVN* igvn) {
} else if (cmp1->Opcode() == Op_CmpF || cmp1->Opcode() == Op_CmpD ||
cmp2->Opcode() == Op_CmpF || cmp2->Opcode() == Op_CmpD ||
cmp1->Opcode() == Op_CmpP || cmp1->Opcode() == Op_CmpN ||
cmp2->Opcode() == Op_CmpP || cmp2->Opcode() == Op_CmpN) {
cmp2->Opcode() == Op_CmpP || cmp2->Opcode() == Op_CmpN ||
cmp1->is_SubTypeCheck() || cmp2->is_SubTypeCheck()) {
// Floats and pointers don't exactly obey trichotomy. To be on the safe side, don't transform their tests.
// SubTypeCheck is not commutative
return false;
} else if (cmp1 != cmp2) {
if (cmp1->in(1) == cmp2->in(2) &&

@ -0,0 +1,68 @@
/*
* 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 8253566
* @summary clazz.isAssignableFrom will return false for interface implementors
* @requires vm.compiler2.enabled
*
* @run main/othervm -XX:-BackgroundCompilation TestSubTypeCheckMacroTrichotomy
*
*/
public class TestSubTypeCheckMacroTrichotomy {
public static void main(String[] args) {
for (int i = 0; i < 20_000; i++) {
final int res1 = test(A.class, B.class);
final int res2 = test(B.class, A.class);
final int res3 = test(A.class, C.class);
if (res1 != 0 || res2 != 1 || res3 != 0) {
throw new RuntimeException("test(A, B) = " + res1 + " test(B, A) = " + res2 + " test(A, C) = " + res3);
}
}
}
private static int test(Class<?> c1, Class<?> c2) {
if (c1 == null) {
}
if (c2 == null) {
}
int res = 0;
if (!c1.isAssignableFrom(c2)) {
if (c2.isAssignableFrom(c1)) {
res = 1;
}
}
return res;
}
private static class A {
}
private static class B extends A {
}
private static class C {
}
}