test/compiler/7044738/Test7044738.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * 2 along with this work; if not, write to the Free Software Foundation,
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/**
 * @test
 * @bug 7044738
 * @summary Loop unroll optimization causes incorrect result
 *
 * @run main/othervm -Xbatch Test7044738
 */

public class Test7044738 {

  private static final int INITSIZE = 10000;
  public int d[] = { 1, 2, 3, 4 };
  public int i, size;

  private static int iter = 5;

  boolean done() { return (--iter > 0); }

  public static void main(String args[]) {
    Test7044738 t = new Test7044738();
    t.test();
  }

  int test() {

    while (done()) {
      size = INITSIZE;

      for (i = 0; i < size; i++) {
        d[0] = d[1]; // 2
        d[1] = d[2]; // 3
        d[2] = d[3]; // 4
        d[3] = d[0]; // 2

        d[0] = d[1]; // 3
        d[1] = d[2]; // 4
        d[2] = d[3]; // 2
        d[3] = d[0]; // 3

        d[0] = d[1]; // 4
        d[1] = d[2]; // 2
        d[2] = d[3]; // 3
        d[3] = d[0]; // 4

        d[0] = d[1]; // 2
        d[1] = d[2]; // 3
        d[2] = d[3]; // 4
        d[3] = d[0]; // 2

        d[0] = d[1]; // 3
        d[1] = d[2]; // 4
        d[2] = d[3]; // 2
        d[3] = d[0]; // 3

        d[0] = d[1]; // 4
        d[1] = d[2]; // 2
        d[2] = d[3]; // 3
        d[3] = d[0]; // 4

        d[0] = d[1]; // 2
        d[1] = d[2]; // 3
        d[2] = d[3]; // 4
        d[3] = d[0]; // 2

        d[0] = d[1]; // 3
        d[1] = d[2]; // 4
        d[2] = d[3]; // 2
        d[3] = d[0]; // 3
      }

      // try to defeat dead code elimination
      if (d[0] == d[1]) {
        System.out.println("test failed: iter=" + iter + "  i=" + i + " d[] = { " + d[0] + ", " + d[1] + ", " + d[2] + ", " + d[3] + " } ");
        System.exit(97);
      }
    }
    return d[3];
  }

}