1 /*

     2  * Copyright 2014 Google, Inc.  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  * @test

    26  * @bug 8043354

    27  * @summary bcEscapeAnalyzer allocated_escapes not conservative enough

    28  *

    29  * @run main/othervm

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

    31  *      compiler.escapeAnalysis.TestAllocatedEscapesPtrComparison

    32  * @author Chuck Rasbold rasbold@google.com

    33  */

    34 

    35 package compiler.escapeAnalysis;

    36 

    37 /*

    38  * Test always passes with -XX:-OptmimizePtrCompare

    39  */

    40 

    41 import java.util.ArrayList;

    42 import java.util.List;

    43 

    44 public class TestAllocatedEscapesPtrComparison {

    45 

    46   static TestAllocatedEscapesPtrComparison dummy;

    47 

    48   class Marker {

    49   }

    50 

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

    52 

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

    54   // by the bytecode escape analyzer.

    55 

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

    57   Marker getMarker() {

    58     // result escapes through markerList

    59     final Marker result = new Marker();

    60     markerList.add(result);

    61     return result;

    62   }

    63 

    64   void visit(int depth) {

    65     // Make a new marker

    66     getMarker();

    67 

    68     // Call visitAndPop every once in a while

    69     // Cap the depth of our recursive visits

    70     if (depth % 10 == 2) {

    71       visitAndPop(depth + 1);

    72     } else if (depth < 15) {

    73       visit(depth + 1);

    74     }

    75   }

    76 

    77    void visitAndPop(int depth) {

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

    79     dummy = new TestAllocatedEscapesPtrComparison();

    80 

    81     // Make a new marker

    82     Marker marker = getMarker();

    83 

    84     visit(depth + 1);

    85 

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

    87     boolean found = false;

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

    89       Marker removed = markerList.remove(i);

    90 

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

    92       if (removed == marker) {

    93         found = true;

    94         break;

    95       }

    96     }

    97 

    98     if (!found) {

    99       throw new RuntimeException("test fails");

   100     }

   101   }

   102 

   103 

   104   public static void main(String args[]) {

   105     TestAllocatedEscapesPtrComparison tc = new TestAllocatedEscapesPtrComparison();

   106 

   107     // Warmup and run enough times

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

   109       tc.visit(0);

   110     }

   111   }

   112 }