8336795: [lworld] JNI MonitorEnter doesn't return the right value when it throws an exception

Author: fparain

src/hotspot/share/prims/jni.cpp

@@ -2818,7 +2818,7 @@ JNI_ENTRY(jint, jni_MonitorEnter(JNIEnv *env, jobject jobj))
   }
 
   Handle obj(thread, JNIHandles::resolve_non_null(jobj));
-  ObjectSynchronizer::jni_enter(obj, thread);
+  ObjectSynchronizer::jni_enter(obj, CHECK_(JNI_ERR));
   return JNI_OK;
 JNI_END
 

test/hotspot/jtreg/runtime/valhalla/inlinetypes/InlineWithJni.java

@@ -34,6 +34,9 @@
 
 public value class InlineWithJni {
 
+    static int returnValue = 999;
+    static final int JNI_ERR = -1;  // from jni.h
+
     static {
         System.loadLibrary("InlineWithJni");
     }
@@ -60,6 +63,7 @@ public static void testJniMonitorOps() {
             sawIe = true;
         }
         Asserts.assertTrue(sawIe, "Missing IdentityException");
+        Asserts.assertEQ(returnValue, JNI_ERR);
         try {
             new InlineWithJni(0).doJniMonitorExit();
         } catch (IllegalMonitorStateException imse) {

test/hotspot/jtreg/runtime/valhalla/inlinetypes/libInlineWithJni.c

@@ -25,7 +25,10 @@
 
 JNIEXPORT void JNICALL
 Java_runtime_valhalla_inlinetypes_InlineWithJni_doJniMonitorEnter(JNIEnv *env, jobject obj) {
-    (*env)->MonitorEnter(env, obj);
+    int ret = (*env)->MonitorEnter(env, obj);
+    jclass class = (*env)->GetObjectClass(env, obj);
+    jfieldID fieldId = (*env)->GetStaticFieldID(env, class, "returnValue", "I");
+    (*env)->SetStaticIntField(env, class, fieldId, ret);
 }
 
 JNIEXPORT void JNICALL