1 /*
   2  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  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
  26  * @bug 8031752
  27  * @summary speculative traps need to be cleaned up at GC
  28  * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-TieredCompilation -XX:-UseOnStackReplacement -XX:-BackgroundCompilation -XX:+UseTypeSpeculation -XX:TypeProfileLevel=222 -XX:CompileCommand=exclude,java.lang.reflect.Method::invoke -XX:CompileCommand=exclude,sun.reflect.DelegatingMethodAccessorImpl::invoke -Xmx512M TestSpecTrapClassUnloading
  29  *
  30  */
  31 
  32 import java.lang.reflect.Method;
  33 
  34 public class TestSpecTrapClassUnloading {
  35     static class B {
  36         final public boolean m(Object o) {
  37             if (o.getClass() == B.class) {
  38                 return true;
  39             }
  40             return false;
  41         }
  42     }
  43 
  44     static class MemoryChunk {
  45         MemoryChunk other;
  46         long[] array;
  47         MemoryChunk(MemoryChunk other) {
  48             this.other = other;
  49             array = new long[1024 * 1024 * 1024];
  50         }
  51     }
  52 
  53     static void m1(B b, Object o) {
  54         b.m(o);
  55     }
  56 
  57     static void m2(B b, Object o) {
  58         b.m(o);
  59     }
  60 
  61     public static void main(String[] args) throws Exception {
  62         Method m = B.class.getMethod("m", Object.class);
  63         Object o = new Object();
  64         B b = new B();
  65 
  66         // add speculative trap in B.m() for m1
  67         for (int i = 0; i < 20000; i++) {
  68             m1(b, b);
  69         }
  70         m1(b, o);
  71 
  72         // add speculative trap in B.m() for code generated by reflection
  73         for (int i = 0; i < 20000; i++) {
  74             m.invoke(b, b);
  75         }
  76         m.invoke(b, o);
  77 
  78         m = null;
  79 
  80         // add speculative trap in B.m() for m2
  81         for (int i = 0; i < 20000; i++) {
  82             m2(b, b);
  83         }
  84         m2(b, o);
  85 
  86         // Exhaust memory which causes the code generated by
  87         // reflection to be unloaded but B.m() is not.
  88         MemoryChunk root = null;
  89         try {
  90             while (true) {
  91                 root = new MemoryChunk(root);
  92             }
  93         } catch(OutOfMemoryError e) {
  94             root = null;
  95         }
  96     }
  97 }