diff test/compiler/5091921/Test6959129.java @ 3345:bad7ecd0b6ed

5091921: Sign flip issues in loop optimizer Summary: Fix integer overflow problem in the code generated by loop optimizer. Reviewed-by: never
author kvn
date Wed, 04 May 2011 13:12:42 -0700
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/compiler/5091921/Test6959129.java	Wed May 04 13:12:42 2011 -0700
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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;
+  }
+}
+