/*

 * Copyright 2014 Google, Inc.  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 8043354

 * @summary bcEscapeAnalyzer allocated_escapes not conservative enough

 *

 * @run main/othervm

 *      -XX:CompileCommand=compileonly,compiler.escapeAnalysis.TestAllocatedEscapesPtrComparison::visitAndPop

 *      compiler.escapeAnalysis.TestAllocatedEscapesPtrComparison

 * @author Chuck Rasbold rasbold@google.com

 */

package compiler.escapeAnalysis;

/*

 * Test always passes with -XX:-OptmimizePtrCompare

 */

import java.util.ArrayList;

import java.util.List;

public class TestAllocatedEscapesPtrComparison {

  static TestAllocatedEscapesPtrComparison dummy;

  class Marker {

  }

  List<Marker> markerList = new ArrayList<>();

  // Suppress compilation of this method, it must be processed

  // by the bytecode escape analyzer.

  // Make a new marker and put it on the List

  Marker getMarker() {

    // result escapes through markerList

    final Marker result = new Marker();

    markerList.add(result);

    return result;

  }

  void visit(int depth) {

    // Make a new marker

    getMarker();

    // Call visitAndPop every once in a while

    // Cap the depth of our recursive visits

    if (depth % 10 == 2) {

      visitAndPop(depth + 1);

    } else if (depth < 15) {

      visit(depth + 1);

    }

  }

   void visitAndPop(int depth) {

    // Random dummy allocation to force EscapeAnalysis to process this method

    dummy = new TestAllocatedEscapesPtrComparison();

    // Make a new marker

    Marker marker = getMarker();

    visit(depth + 1);

    // Walk and pop the marker list up to the current marker

    boolean found = false;

    for (int i = markerList.size() - 1; i >= 0; i--) {

      Marker removed = markerList.remove(i);

      // In the failure, EA mistakenly converts this comparison to false

      if (removed == marker) {

        found = true;

        break;

      }

    }

    if (!found) {

      throw new RuntimeException("test fails");

    }

  }

  public static void main(String args[]) {

    TestAllocatedEscapesPtrComparison tc = new TestAllocatedEscapesPtrComparison();

    // Warmup and run enough times

    for (int i = 0; i < 20000; i++) {

      tc.visit(0);

    }

  }

}