--- a/src/hotspot/cpu/s390/templateInterpreterGenerator_s390.cpp	Mon Aug 20 15:10:20 2018 -0700
+++ b/src/hotspot/cpu/s390/templateInterpreterGenerator_s390.cpp	Tue Aug 21 09:25:06 2018 +0200
@@ -1681,7 +1681,7 @@
   __ z_lg(Z_R1/*active_handles*/, thread_(active_handles));
   __ clear_mem(Address(Z_R1, JNIHandleBlock::top_offset_in_bytes()), 4);
 
-  // Bandle exceptions (exception handling will handle unlocking!).
+  // Handle exceptions (exception handling will handle unlocking!).
   {
     Label L;
     __ load_and_test_long(Z_R0/*pending_exception*/, thread_(pending_exception));
@@ -1710,17 +1710,9 @@
   __ notify_method_exit(true/*native_method*/, ilgl, InterpreterMacroAssembler::NotifyJVMTI);
 
   // Move native method result back into proper registers and return.
-  // C++ interpreter does not use result handler. So do we need to here? TODO(ZASM): check if correct.
-  { NearLabel no_oop_or_null;
   __ mem2freg_opt(Z_FRET, Address(Z_fp, _z_ijava_state_neg(fresult)));
-  __ load_and_test_long(Z_RET, Address(Z_fp, _z_ijava_state_neg(lresult)));
-  __ z_bre(no_oop_or_null); // No unboxing if the result is NULL.
-  __ load_absolute_address(Z_R1, AbstractInterpreter::result_handler(T_OBJECT));
-  __ compareU64_and_branch(Z_R1, Rresult_handler, Assembler::bcondNotEqual, no_oop_or_null);
-  __ z_lg(Z_RET, oop_tmp_offset, Z_fp);
-  __ verify_oop(Z_RET);
-  __ bind(no_oop_or_null);
-  }
+  __ mem2reg_opt(Z_RET, Address(Z_fp, _z_ijava_state_neg(lresult)));
+  __ call_stub(Rresult_handler);
 
   // Pop the native method's interpreter frame.
   __ pop_interpreter_frame(Z_R14 /*return_pc*/, Z_ARG2/*tmp1*/, Z_ARG3/*tmp2*/);

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/jtreg/runtime/BoolReturn/JNIBooleanTest.java	Tue Aug 21 09:25:06 2018 +0200
@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2018 SAP SE. 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 8209637
+ * @summary [s390x] Interpreter doesn't call result handler after native calls
+ * @author Volker Simonis
+ *
+ * @run main/othervm/native -XX:-UseOnStackReplacement -Xbatch JNIBooleanTest 50000
+ * @run main/othervm/native -Xint JNIBooleanTest 256
+ */
+
+import java.lang.reflect.Method;
+
+public class JNIBooleanTest {
+  static native boolean foo(byte b);
+
+  static boolean bar(byte b) {
+    return foo(b);
+  }
+
+  public static void main(String args[]) throws Exception {
+    int count = args.length > 0 ? Integer.parseInt(args[0]) : 50_000;
+    byte b = 0;
+    for (int i = 0; i < count; i++) {
+      boolean bool = foo(b);
+      if ((b == 0 && bool) || (b != 0 && !bool)) {
+        throw new RuntimeException("Error: foo(" + b + ") = " + bool + " in iteration " + i);
+      }
+      b++;
+    }
+
+    b = 0;
+    for (int i = 0; i < count; i++) {
+      boolean bool = bar(b);
+      if ((b == 0 && bool) || (b != 0 && !bool)) {
+        throw new RuntimeException("Error: bar(" + b + ") = " + bool + " in iteration " + i);
+      }
+      b++;
+    }
+
+    Method foo = JNIBooleanTest.class.getDeclaredMethod("foo", byte.class);
+
+    b = 0;
+    for (int i = 0; i < count; i++) {
+      boolean bool = ((Boolean)foo.invoke(null, b)).booleanValue();
+      if ((b == 0 && bool) || (b != 0 && !bool)) {
+        throw new RuntimeException("Error: foo(" + b + ") = " + bool + " in iteration " + i + " (reflective)");
+      }
+      b++;
+    }
+
+    Method bar = JNIBooleanTest.class.getDeclaredMethod("bar", byte.class);
+
+    b = 0;
+    for (int i = 0; i < count; i++) {
+      boolean bool = ((Boolean)bar.invoke(null, b)).booleanValue();
+      if ((b == 0 && bool) || (b != 0 && !bool)) {
+        throw new RuntimeException("Error: bar(" + b + ") = " + bool + " in iteration " + i + " (reflective)");
+      }
+      b++;
+    }
+  }
+
+  static {
+    System.loadLibrary("JNIBooleanTest");
+  }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/jtreg/runtime/BoolReturn/libJNIBooleanTest.c	Tue Aug 21 09:25:06 2018 +0200
@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2018 SAP SE. 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"
+
+JNIEXPORT jboolean JNICALL
+Java_JNIBooleanTest_foo(JNIEnv *env, jclass cls, jbyte b) {
+  jboolean old = b;
+  return old;
+}