view test/compiler/5091921/Test6959129.java @ 9010:08a16c26907f

MX_TESTFILE environment variable can be used to specify (and preserve) the test list file used by 'mx unittest'. This is useful when wanting to run the command under gdb.
author Doug Simon <doug.simon@oracle.com>
date Thu, 11 Apr 2013 21:40:52 +0200
parents bad7ecd0b6ed
children
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/*
 * Copyright (c) 2011, Oracle and/or its affiliates. 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 6959129
 * @summary COMPARISON WITH INTEGER.MAX_INT DOES NOT WORK CORRECTLY IN THE CLIENT VM.
 *
 * @run main/othervm -ea Test6959129
 */

public class Test6959129 {

  public static void main(String[] args) {
    long start  = System.currentTimeMillis();
    int min = Integer.MAX_VALUE-30000;
    int max = Integer.MAX_VALUE;
    long maxmoves = 0;
    try {
      maxmoves = maxMoves(min, max);
    } catch (AssertionError e) {
      System.out.println("Passed");
      System.exit(95);
    }
    System.out.println("maxMove:" + maxmoves);
    System.out.println("FAILED");
    System.exit(97);
  }
  /**
   * Imperative implementation that returns the length hailstone moves
   * for a given number.
   */
  public static long hailstoneLengthImp(long n) {
    long moves = 0;
    while (n != 1) {
      assert n > 1;
      if (isEven(n)) {
        n = n / 2;
      } else {
        n = 3 * n + 1;
      }
      ++moves;
    }
    return moves;
  }

  private static boolean isEven(long n) {
    return n % 2 == 0;
  }

  /**
   * Returns the maximum length of the hailstone sequence for numbers
   * between min to max.
   *
   * For rec1 - Assume that min is bigger than max.
   */
  public static long maxMoves(int min, int max) {
    long maxmoves = 0;
    for (int n = min; n <= max; n++) {
      if ((n & 1023) == 0) System.out.println(n);
      long moves = hailstoneLengthImp(n);
      if (moves > maxmoves) {
        maxmoves = moves;
      }
    }
    return maxmoves;
  }
}