sam-t2/sam/cpus/vonk/ss/lib/cpu/src/SS_Chain.h

/*
* ========== Copyright Header Begin ==========================================
*
* OpenSPARC T2 Processor File: SS_Chain.h
* Copyright (c) 2006 Sun Microsystems, Inc.  All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES.
*
* The above named program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License version 2 as published by the Free Software Foundation.
*
* The above named program is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this work; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
*
* ========== Copyright Header End ============================================
*/

#ifndef __SS_Chain_h__
#define __SS_Chain_h__

// SS_Chain is node element of a basic cyclic double linked list
// data structure.

class SS_Chain
{
  public:
    SS_Chain() : prev(this), next(this) {}

    // The SS_Chanin class is used in "nasty" pointer arithmetic and
    // this union is for makeing this struction 16 bytes in size in
    // v8plus compilation mode.

    union
    {
      SS_Chain* prev;
      uint64_t align0;
    };

    union
    {
      SS_Chain* next;
      uint64_t align1;
    };

    // clean() turns this node into a single element cyclio
    // double linked list.
    void clean()
    {
      prev = next = this;
    }

    // unlink() removes this chian node from the cyclic double
    // linked list.
    void unlink()
    {
      next->prev = prev;
      prev->next = next;
    }

    // insert_after() inserts this after that node in the cyclic
    // doule linked list.
    void insert_after( SS_Chain* node )
    {
      next = node->next;
      next->prev = this;
      prev = node;
      node->next = this;
    }
};


#endif