1 /*
   2  * Copyright (c) 2006, 2017, 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.code;
  26 
  27 import java.util.*;
  28 
  29 import sun.jvm.hotspot.debugger.*;
  30 import sun.jvm.hotspot.runtime.*;
  31 import sun.jvm.hotspot.types.*;
  32 import sun.jvm.hotspot.utilities.*;
  33 
  34 public class VMRegImpl {
  35 
  36   private static VMReg stack0;
  37   private static int stack0Val;
  38   private static Address stack0Addr;
  39   private static AddressField regNameField;
  40   private static int stackSlotSize;
  41 
  42   static {
  43     VM.registerVMInitializedObserver(new Observer() {
  44         public void update(Observable o, Object data) {
  45           initialize(VM.getVM().getTypeDataBase());
  46         }
  47       });
  48   }
  49 
  50   private static void initialize(TypeDataBase db) {
  51     Type type = db.lookupType("VMRegImpl");
  52     AddressField stack0Field = type.getAddressField("stack0");
  53     stack0Addr = stack0Field.getValue();
  54     stack0Val = (int) stack0Addr.hashCode();
  55     stack0 = new VMReg(stack0Val);
  56     regNameField = type.getAddressField("regName[0]");
  57     stackSlotSize = db.lookupIntConstant("VMRegImpl::stack_slot_size");
  58   }
  59 
  60   public static VMReg getStack0() {
  61     return stack0;
  62   }
  63 
  64   public static String getRegisterName(int index) {
  65     if (Assert.ASSERTS_ENABLED) {
  66       Assert.that(index >= 0 && index < stack0Val, "invalid index : " + index);
  67     }
  68     Address regName = regNameField.getStaticFieldAddress();
  69     long addrSize = VM.getVM().getAddressSize();
  70     return CStringUtilities.getString(regName.getAddressAt(index * addrSize));
  71   }
  72 
  73   public static int getStackSlotSize() {
  74     return stackSlotSize;
  75   }
  76 }
--- EOF ---