14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test NullCheckDroppingsTest
  26  * @bug 8054492
  27  * @summary "Casting can result in redundant null checks in generated code"
  28  * @library /testlibrary /../../test/lib /testlibrary/com/oracle/java/testlibrary
  29  * @modules java.base/sun.misc
  30  *          java.management
  31  * @build NullCheckDroppingsTest
  32  * @run main ClassFileInstaller sun.hotspot.WhiteBox
  33  *                              sun.hotspot.WhiteBox$WhiteBoxPermission
  34  * @run main ClassFileInstaller com.oracle.java.testlibrary.Platform
  35  * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
  36  *                   -Xmixed -XX:-BackgroundCompilation -XX:-TieredCompilation -XX:CompileThreshold=1000
  37  *                   -XX:CompileCommand=exclude,NullCheckDroppingsTest::runTest NullCheckDroppingsTest
  38  */
  39 
  40 import sun.hotspot.WhiteBox;
  41 import sun.hotspot.code.NMethod;
  42 import com.oracle.java.testlibrary.Platform;
  43 
  44 import java.lang.reflect.Method;
  45 import java.lang.invoke.MethodHandle;
  46 import java.lang.invoke.MethodHandles;
  47 import java.lang.invoke.MethodType;
  48 import java.util.function.BiFunction;
  49 
  50 public class NullCheckDroppingsTest {
  51 
  52     private static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();
  53 
  54     static final BiFunction<Class, Object, Object> fCast = (c, o) -> c.cast(o);
  55 
  56     static final MethodHandle SET_SSINK;
  57     static final MethodHandle MH_CAST;
  58 
  59     static {
  60         try {
  61             SET_SSINK = MethodHandles.lookup().findSetter(NullCheckDroppingsTest.class, "ssink", String.class);
  62             MH_CAST = MethodHandles.lookup().findVirtual(Class.class,

  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test NullCheckDroppingsTest
  26  * @bug 8054492
  27  * @summary "Casting can result in redundant null checks in generated code"
  28  * @library /testlibrary /../../test/lib /testlibrary/com/oracle/java/testlibrary
  29  * @modules java.base/sun.misc
  30  *          java.management
  31  * @build NullCheckDroppingsTest
  32  * @run main ClassFileInstaller sun.hotspot.WhiteBox
  33  *                              sun.hotspot.WhiteBox$WhiteBoxPermission
  34  * @run main ClassFileInstaller jdk.test.lib.Platform
  35  * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
  36  *                   -Xmixed -XX:-BackgroundCompilation -XX:-TieredCompilation -XX:CompileThreshold=1000
  37  *                   -XX:CompileCommand=exclude,NullCheckDroppingsTest::runTest NullCheckDroppingsTest
  38  */
  39 
  40 import sun.hotspot.WhiteBox;
  41 import sun.hotspot.code.NMethod;
  42 import jdk.test.lib.Platform;
  43 
  44 import java.lang.reflect.Method;
  45 import java.lang.invoke.MethodHandle;
  46 import java.lang.invoke.MethodHandles;
  47 import java.lang.invoke.MethodType;
  48 import java.util.function.BiFunction;
  49 
  50 public class NullCheckDroppingsTest {
  51 
  52     private static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();
  53 
  54     static final BiFunction<Class, Object, Object> fCast = (c, o) -> c.cast(o);
  55 
  56     static final MethodHandle SET_SSINK;
  57     static final MethodHandle MH_CAST;
  58 
  59     static {
  60         try {
  61             SET_SSINK = MethodHandles.lookup().findSetter(NullCheckDroppingsTest.class, "ssink", String.class);
  62             MH_CAST = MethodHandles.lookup().findVirtual(Class.class,