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/*
* Copyright (c) 2012, 2015, 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 7190310
* @summary Inlining WeakReference.get(), and hoisting $referent may lead to non-terminating loops
* @modules java.base/jdk.internal.misc:+open
* @modules java.base/java.lang.ref:open
*
* @run main/othervm -Xbatch compiler.c2.Test7190310_unsafe
*/
package compiler.c2;
import jdk.internal.misc.Unsafe;
import java.lang.ref.Reference;
import java.lang.ref.WeakReference;
import java.lang.reflect.Field;
public class Test7190310_unsafe {
static class TestObject {
public String toString() {
return "TestObject";
}
}
;
private static TestObject str = new TestObject();
private static final WeakReference ref = new WeakReference(str);
private TestObject obj;
public static void main(String[] args) throws Exception {
Class c = Test7190310_unsafe.class.getClassLoader().loadClass("jdk.internal.misc.Unsafe");
Field f = c.getDeclaredField("theUnsafe");
f.setAccessible(true);
Unsafe unsafe = (Unsafe) f.get(c);
f = Reference.class.getDeclaredField("referent");
f.setAccessible(true);
long referent_offset = unsafe.objectFieldOffset(f);
Test7190310_unsafe t = new Test7190310_unsafe();
TestObject o = new TestObject();
t.obj = o;
// Warmup (compile methods)
System.err.println("Warmup");
Object obj = null;
for (int i = 0; i < 11000; i++) {
obj = getRef0(ref);
}
for (int i = 0; i < 11000; i++) {
obj = getRef1(unsafe, ref, referent_offset);
}
for (int i = 0; i < 11000; i++) {
obj = getRef2(unsafe, ref, referent_offset);
}
for (int i = 0; i < 11000; i++) {
obj = getRef3(unsafe, ref, referent_offset);
}
for (int i = 0; i < 11000; i++) {
obj = getRef4(unsafe, t, referent_offset);
}
// Access verification
System.err.println("Verification");
if (!verifyGet(referent_offset, unsafe)) {
System.exit(97);
}
obj = getRef3(unsafe, t, referent_offset);
if (obj != o) {
System.out.println("FAILED: unsafe.getObject(Object, " + referent_offset + ") " + obj + " != " + o);
System.exit(97);
}
obj = getRef4(unsafe, t, referent_offset);
if (obj != o) {
System.out.println("FAILED: unsafe.getObject(Test7190310, " + referent_offset + ") " + obj + " != " + o);
System.exit(97);
}
}
static boolean verifyGet(long referent_offset, Unsafe unsafe) throws Exception {
// Access verification
System.out.println("referent: " + str);
Object obj = getRef0(ref);
if (obj != str) {
System.out.println("FAILED: weakRef.get() " + obj + " != " + str);
return false;
}
obj = getRef1(unsafe, ref, referent_offset);
if (obj != str) {
System.out.println("FAILED: unsafe.getObject(weakRef, " + referent_offset + ") " + obj + " != " + str);
return false;
}
obj = getRef2(unsafe, ref, referent_offset);
if (obj != str) {
System.out.println("FAILED: unsafe.getObject(abstRef, " + referent_offset + ") " + obj + " != " + str);
return false;
}
obj = getRef3(unsafe, ref, referent_offset);
if (obj != str) {
System.out.println("FAILED: unsafe.getObject(Object, " + referent_offset + ") " + obj + " != " + str);
return false;
}
return true;
}
static Object getRef0(WeakReference ref) throws Exception {
return ref.get();
}
static Object getRef1(Unsafe unsafe, WeakReference ref, long referent_offset) throws Exception {
return unsafe.getObject(ref, referent_offset);
}
static Object getRef2(Unsafe unsafe, Reference ref, long referent_offset) throws Exception {
return unsafe.getObject(ref, referent_offset);
}
static Object getRef3(Unsafe unsafe, Object ref, long referent_offset) throws Exception {
return unsafe.getObject(ref, referent_offset);
}
static Object getRef4(Unsafe unsafe, Test7190310_unsafe ref, long referent_offset) throws Exception {
return unsafe.getObject(ref, referent_offset);
}
}
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