1 /*
   2  * Copyright (c) 2017, 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 
  25 package sun.jvm.hotspot.gc.g1;
  26 
  27 import java.util.Observable;
  28 import java.util.Observer;
  29 import sun.jvm.hotspot.debugger.Address;
  30 import sun.jvm.hotspot.runtime.VM;
  31 import sun.jvm.hotspot.runtime.VMObject;
  32 import sun.jvm.hotspot.types.CIntegerField;
  33 import sun.jvm.hotspot.types.Type;
  34 import sun.jvm.hotspot.types.TypeDataBase;
  35 
  36 // Mirror class for HeapRegionType. Currently we don't actually include
  37 // any of its fields but only iterate over it.
  38 
  39 public class HeapRegionType extends VMObject {
  40 
  41     private static int freeTag;
  42     private static int youngMask;
  43     private static int edenTag;
  44     private static int survTag;
  45     private static int humongousMask;
  46     private static int startsHumongousTag;
  47     private static int continuesHumongousTag;
  48     private static int pinnedMask;
  49     private static int archiveMask;
  50     private static int oldMask;
  51     private static CIntegerField tagField;
  52     private int tag;
  53 
  54     static {
  55         VM.registerVMInitializedObserver(new Observer() {
  56                 public void update(Observable o, Object data) {
  57                     initialize(VM.getVM().getTypeDataBase());
  58                 }
  59         });
  60     }
  61 
  62     private static synchronized void initialize(TypeDataBase db) {
  63         Type type = db.lookupType("HeapRegionType");
  64 
  65         tagField = type.getCIntegerField("_tag");
  66 
  67         freeTag = db.lookupIntConstant("HeapRegionType::FreeTag");
  68         youngMask = db.lookupIntConstant("HeapRegionType::YoungMask");
  69         edenTag = db.lookupIntConstant("HeapRegionType::EdenTag");
  70         survTag = db.lookupIntConstant("HeapRegionType::SurvTag");
  71         startsHumongousTag = db.lookupIntConstant("HeapRegionType::StartsHumongousTag");
  72         continuesHumongousTag = db.lookupIntConstant("HeapRegionType::ContinuesHumongousTag");
  73         archiveMask = db.lookupIntConstant("HeapRegionType::ArchiveMask");
  74         humongousMask = db.lookupIntConstant("HeapRegionType::HumongousMask");
  75         pinnedMask = db.lookupIntConstant("HeapRegionType::PinnedMask");
  76         oldMask = db.lookupIntConstant("HeapRegionType::OldMask");
  77     }
  78 
  79     public boolean isFree() {
  80         return tagField.getValue(addr) == freeTag;
  81     }
  82 
  83     public boolean isEden() {
  84         return tagField.getValue(addr) == edenTag;
  85     }
  86 
  87     public boolean isSurvivor() {
  88         return tagField.getValue(addr) == survTag;
  89     }
  90 
  91     public boolean isYoung() {
  92         return (tagField.getValue(addr) & youngMask) != 0;
  93     }
  94 
  95     public boolean isHumongous() {
  96         return (tagField.getValue(addr) & humongousMask) != 0;
  97     }
  98 
  99     public boolean isStartsHumongous() {
 100         return tagField.getValue(addr) == startsHumongousTag;
 101     }
 102 
 103     public boolean isContinuesHumongous() {
 104         return tagField.getValue(addr) == continuesHumongousTag;
 105     }
 106 
 107     public boolean isArchive() {
 108         return (tagField.getValue(addr) & archiveMask) != 0;
 109     }
 110 
 111     public boolean isPinned() {
 112         return (tagField.getValue(addr) & pinnedMask) != 0;
 113     }
 114 
 115     public boolean isOld() {
 116         return (tagField.getValue(addr) & oldMask) != 0;
 117     }
 118 
 119     public HeapRegionType(Address addr) {
 120         super(addr);
 121     }
 122 
 123     public String typeAnnotation() {
 124         if (isFree()) {
 125             return "Free";
 126         }
 127         if (isEden()) {
 128             return "Eden";
 129         }
 130         if (isSurvivor()) {
 131             return "Survivor";
 132         }
 133         if (isStartsHumongous()) {
 134             return "StartsHumongous";
 135         }
 136         if (isContinuesHumongous()) {
 137             return "ContinuesHumongous";
 138         }
 139         if (isArchive()) {
 140             return "Archive";
 141         }
 142         if (isPinned()) {
 143             return "Pinned";
 144         }
 145         if (isOld()) {
 146             return "Old";
 147         }
 148         return "Unknown Region Type";
 149     }
 150 }