1 /*
   2  * Copyright (c) 1997, 2000, 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 // Data structure for holding monitors for one activation during
  26 // deoptimization.
  27 
  28 class MonitorChunk: public CHeapObj {
  29  private:
  30   int              _number_of_monitors;
  31   BasicObjectLock* _monitors;
  32   BasicObjectLock* monitors() const { return _monitors; }
  33   MonitorChunk*    _next;
  34  public:
  35   // Constructor
  36   MonitorChunk(int number_on_monitors);
  37   ~MonitorChunk();
  38 
  39   // link operations
  40   MonitorChunk* next() const                { return _next; }
  41   void set_next(MonitorChunk* next)         { _next = next; }
  42 
  43   // Tells whether the monitor chunk is linked into the JavaThread
  44   bool is_linked() const                    { return next() != NULL; }
  45 
  46   // Returns the number of monitors
  47   int number_of_monitors() const { return _number_of_monitors; }
  48 
  49   // Returns the index'th monitor
  50   BasicObjectLock* at(int index)            { assert(index >= 0 && index < number_of_monitors(), "out of bounds check"); return &monitors()[index]; }
  51 
  52 
  53   // Memory management
  54   void oops_do(OopClosure* f);
  55 
  56   // Tells whether the addr point into the monitors.
  57   bool contains(void* addr) const           { return (addr >= (void*) monitors()) && (addr <  (void*) (monitors() + number_of_monitors())); }
  58 };