1 /*
   2  * Copyright 2003-2005 Sun Microsystems, Inc.  All Rights Reserved.
   3  * Copyright 2007, 2008 Red Hat, Inc.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  */
  25 
  26  public:
  27   // Each arch must define reset, save, restore
  28   // These are used by objects that only care about:
  29   //  1 - initializing a new state (thread creation, javaCalls)
  30   //  2 - saving a current state (javaCalls)
  31   //  3 - restoring an old state (javaCalls)
  32 
  33   void clear() {
  34     // clearing _last_Java_sp must be first
  35     _last_Java_sp = NULL;
  36     // fence?
  37     _last_Java_pc = NULL;
  38   }
  39 
  40   void copy(JavaFrameAnchor* src) {
  41     // In order to make sure the transition state is valid for "this"
  42     // We must clear _last_Java_sp before copying the rest of the new
  43     // data
  44     //
  45     // Hack Alert: Temporary bugfix for 4717480/4721647 To act like
  46     // previous version (pd_cache_state) don't NULL _last_Java_sp
  47     // unless the value is changing
  48     //
  49     if (_last_Java_sp != src->_last_Java_sp)
  50       _last_Java_sp = NULL;
  51 
  52     _last_Java_pc = src->_last_Java_pc;
  53     // Must be last so profiler will always see valid frame if
  54     // has_last_frame() is true
  55     _last_Java_sp = src->_last_Java_sp;
  56   }
  57 
  58   bool walkable() {
  59     return true;
  60   }
  61 
  62   void make_walkable(JavaThread* thread) {
  63     // nothing to do
  64   }
  65 
  66   intptr_t* last_Java_sp() const {
  67     return _last_Java_sp;
  68   }
  69 
  70   void set_last_Java_sp(intptr_t* sp) {
  71     _last_Java_sp = sp;
  72   }