8251152: ARM32: jtreg c2 Test8202414 test crash

Some CPUs (like ARM32) does not support unaligned memory accesses. To avoid JVM crashes tests that perform such accesses should be skipped on corresponding platforms.

Reviewed-by: phh
Backport-of: 70d5cac

test/hotspot/jtreg/compiler/c2/Test8202414.java

@@ -26,6 +26,8 @@
  * @bug 8202414
  * @summary Unsafe write after primitive array creation may result in array length change
  * @requires (os.arch != "sparc") & (os.arch != "sparcv9")
+ * @modules java.base/jdk.internal.misc
+ * @library /test/lib
  * @run main/othervm compiler.c2.Test8202414
  */
 
@@ -35,10 +37,18 @@
 import java.lang.reflect.Field;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
+import jtreg.SkippedException;
 
 public class Test8202414 {
 
     public static void main(String[] args) {
+        // Some CPUs (for example, ARM) does not support unaligned
+        // memory accesses. This test may cause JVM crash due to
+        // alignment check failure on such CPUs.
+        if (!jdk.internal.misc.Unsafe.getUnsafe().unalignedAccess()) {
+          throw new SkippedException(
+            "Platform is missing unaligned memory accesses support.");
+        }
         System.err.close();
         int count = 0;
         while (count++ < 120000) {

test/hotspot/jtreg/compiler/unsafe/JdkInternalMiscUnsafeUnalignedAccess.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016 SAP SE. All rights reserved.
+ * Copyright (c) 2016, 2020 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
@@ -26,7 +26,7 @@
  * @bug 8158260
  * @summary Test unaligned Unsafe accesses
  * @modules java.base/jdk.internal.misc:+open
- *
+ * @library /test/lib
  * @run main/othervm -Diters=20000 -XX:-UseOnStackReplacement -XX:-BackgroundCompilation
  *      compiler.unsafe.JdkInternalMiscUnsafeUnalignedAccess
  * @author volker.simonis@gmail.com
@@ -38,6 +38,7 @@
 
 import java.lang.reflect.Field;
 import java.nio.ByteOrder;
+import jtreg.SkippedException;
 
 public class JdkInternalMiscUnsafeUnalignedAccess {
     static final int ITERS = Integer.getInteger("iters", 20_000);
@@ -131,8 +132,7 @@ static void putLong_17(long l) {
     public static void main(String[] args) throws Exception {
 
         if (!UNSAFE.unalignedAccess()) {
-            System.out.println("Platform is not supporting unaligned access - nothing to test.");
-            return;
+            throw new SkippedException("Platform is not supporting unaligned access - nothing to test.");
         }
 
         memory = UNSAFE.allocateMemory(SIZE);