Invoke teardown hooks in Shutdown#exit substitution

Author: DSouzaM

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jdk/Target_java_lang_Shutdown.java

@@ -25,10 +25,10 @@
 package com.oracle.svm.core.jdk;
 
 import com.oracle.svm.core.annotate.Alias;
+import com.oracle.svm.core.annotate.Delete;
 import com.oracle.svm.core.annotate.RecomputeFieldValue;
 import com.oracle.svm.core.annotate.Substitute;
 import com.oracle.svm.core.annotate.TargetClass;
-import com.oracle.svm.core.annotate.TargetElement;
 import com.oracle.svm.core.util.VMError;
 
 @TargetClass(className = "java.lang.Shutdown")
@@ -45,23 +45,41 @@ public final class Target_java_lang_Shutdown {
         hooks[Util_java_lang_Shutdown.NATIVE_IMAGE_SHUTDOWN_HOOKS_SLOT] = RuntimeSupport::executeShutdownHooks;
     }
 
-    @Substitute
-    static void beforeHalt() {
-    }
-
     /**
      * Invoked by the JNI DestroyJavaVM procedure when the last non-daemon thread has finished.
      * Unlike the exit method, this method does not actually halt the VM.
      */
     @Alias
     static native void shutdown();
 
+    @Delete
+    private static native void logRuntimeExit(int status);
+
+    @Delete
+    static native void beforeHalt();
+
+    /**
+     * This substitution makes a few modifications to {@code Shutdown#exit}:
+     * <ul>
+     * <li>it omits {@code logRuntimeExit} (exit logging is disabled: GR-45418/JDK-8301627).</li>
+     * <li>it omits {@code beforeHalt} (not implemented).</li>
+     * <li>it runs teardown hooks after running shutdown hooks and before halting.</li>
+     * </ul>
+     */
     @Substitute
-    @TargetElement
-    @SuppressWarnings("unused")
-    private static void logRuntimeExit(int status) {
-        // Disable exit logging (GR-45418/JDK-8301627)
+    static void exit(int status) {
+        synchronized (Target_java_lang_Shutdown.class) {
+            runHooks();
+            RuntimeSupport.executeTearDownHooks();
+            halt(status);
+        }
     }
+
+    @Alias
+    static native void runHooks();
+
+    @Alias
+    static native void halt(int status);
 }
 
 /** Utility methods for Target_java_lang_Shutdown. */