1 /*

     2  * Copyright (c) 2014, 2018, Oracle and/or its affiliates. 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 #include "precompiled.hpp"

    25 #include "classfile/javaClasses.inline.hpp"

    26 #include "jfr/leakprofiler/chains/edge.hpp"

    27 #include "jfr/leakprofiler/utilities/unifiedOop.hpp"

    28 

    29 Edge::Edge() : _parent(NULL), _reference(NULL) {}

    30 

    31 Edge::Edge(const Edge* parent, const oop* reference) : _parent(parent),

    32                                                        _reference(reference) {}

    33 

    34 const oop Edge::pointee() const {

    35   return UnifiedOop::dereference(_reference);

    36 }

    37 

    38 const oop Edge::reference_owner() const {

    39   return is_root() ? (oop)NULL : UnifiedOop::dereference(_parent->reference());

    40 }

    41 

    42 static const Klass* resolve_klass(const oop obj) {

    43   assert(obj != NULL, "invariant");

    44   return java_lang_Class::is_instance(obj) ?

    45     java_lang_Class::as_Klass(obj) : obj->klass();

    46 }

    47 

    48 const Klass* Edge::pointee_klass() const {

    49   return resolve_klass(pointee());

    50 }

    51 

    52 const Klass* Edge::reference_owner_klass() const {

    53   const oop ref_owner = reference_owner();

    54   return ref_owner != NULL ? resolve_klass(ref_owner) : NULL;

    55 }

    56 

    57 size_t Edge::distance_to_root() const {

    58   size_t depth = 0;

    59   const Edge* current = _parent;

    60   while (current != NULL) {

    61     depth++;

    62     current = current->parent();

    63   }

    64   return depth;

    65 }