jdk-24/hotspot/test/runtime/jni/CallWithJNIWeak/libCallWithJNIWeak.c
Kim Barrett 28477cf493 8166188: G1 Needs pre barrier on dereference of weak JNI handles
Add low tag to jweaks and G1 barrier for jweak loads.

Co-authored-by: Martin Doerr <martin.doerr@sap.com>
Co-authored-by: Volker Simonis <volker.simonis@sap.com>
Reviewed-by: mgerdin, mdoerr, pliden, dlong, dcubed, coleenp, aph, tschatzl
2017-02-15 22:19:13 -05:00

54 lines
1.9 KiB
C

/*
* Copyright (c) 2017, 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.
*/
#include <jni.h>
/*
* Class: CallWithJNIWeak
* Method: doStuff
* Signature: (Ljava/lang/Object;)Ljava/lang/Object;
*/
JNIEXPORT jobject JNICALL
Java_CallWithJNIWeak_doStuff(JNIEnv *env, jclass c, jobject o) {
jmethodID id = (*env)->GetStaticMethodID(
env, c, "doWithWeak", "(Ljava/lang/Object;)Ljava/lang/Object;");
jweak w = (*env)->NewWeakGlobalRef(env, o);
jobject param = w;
(*env)->CallStaticVoidMethod(env, c, id, param);
return param;
}
/*
* Class: CallWithJNIWeak
* Method: doWithWeak
* Signature: (Ljava/lang/Object;)Ljava/lang/Object;
*/
JNIEXPORT jobject JNICALL
Java_CallWithJNIWeak_doWithWeak(JNIEnv *env, jclass c, jobject o) {
jclass thr_class = (*env)->GetObjectClass(env, o); // o is java.lang.Thread
jmethodID id = (*env)->GetMethodID(env, thr_class, "isInterrupted", "()Z");
jboolean b = (*env)->CallBooleanMethod(env, o, id);
return o;
}