1 /*
   2  * Copyright (c) 2016, 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 /**
  26  * @test
  27  * @bug 8148175
  28  *
  29  * @ignore 8153194
  30  * @run main/othervm/timeout=300 -Xbatch -Xmx128m
  31  *      compiler.gcbarriers.PreserveFPRegistersTest
  32  */
  33 
  34 package compiler.gcbarriers;
  35 
  36 public class PreserveFPRegistersTest {
  37 
  38     public static void main(String... args) throws InterruptedException {
  39         new PreserveFPRegistersTest().go();
  40     }
  41 
  42     public final Object[][] storage;
  43 
  44     /**
  45      * Number of objects per region.
  46      */
  47     public final int K = 10;
  48 
  49     /**
  50      * Length of object array: sizeOf(Object[N]) ~= regionSize / K .
  51      */
  52     public final int N;
  53 
  54     /**
  55      * How many regions involved into testing.
  56      */
  57     public final int regionCount;
  58 
  59     PreserveFPRegistersTest() {
  60         long regionSize = 1_000_000; //WB.g1RegionSize();
  61 
  62         Runtime rt = Runtime.getRuntime();
  63         long used = rt.totalMemory() - rt.freeMemory();
  64         long totalFree = rt.maxMemory() - used;
  65         regionCount = (int) ( (totalFree / regionSize) * 0.9);
  66         int refSize = 4;
  67 
  68         N = (int) ((regionSize / K ) / refSize) - 5;
  69         storage = new Object[regionCount * K][];
  70         for (int i = 0; i < storage.length; i++) {
  71             storage[i] = new Object[N];
  72         }
  73     }
  74 
  75     public void go() throws InterruptedException {
  76         final float FINAL = getValue();
  77 
  78         for (int to = 0; to < regionCount; to++) {
  79             Object celebrity = storage[to * K];
  80             for (int from = 0; from < regionCount; from++) {
  81                 for (int rn = 0; rn != 100; rn++) {
  82                     storage[getY(to, from, rn)][getX(to, from, rn)] = celebrity;
  83                 }
  84                 if (FINAL != getValue()) {
  85                     throw new AssertionError("Final value has changed: " + FINAL + " != " + getValue());
  86                 }
  87             }
  88         }
  89 
  90         System.out.println("TEST PASSED");
  91     }
  92 
  93     public float getValue() {
  94         return 6;
  95     }
  96 
  97     private int getX(int to, int from, int rn) {
  98         return (rn*regionCount + to) % N;
  99     }
 100 
 101     private int getY(int to, int from, int rn) {
 102         return ((rn*regionCount + to) / N + from * K) % (regionCount*K) ;
 103     }
 104 }