1  // Low-level type for atomic operations -*- C++ -*-
       2  
       3  // Copyright (C) 2004-2023 Free Software Foundation, Inc.
       4  //
       5  // This file is part of the GNU ISO C++ Library.  This library is free
       6  // software; you can redistribute it and/or modify it under the
       7  // terms of the GNU General Public License as published by the
       8  // Free Software Foundation; either version 3, or (at your option)
       9  // any later version.
      10  
      11  // This library is distributed in the hope that it will be useful,
      12  // but WITHOUT ANY WARRANTY; without even the implied warranty of
      13  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      14  // GNU General Public License for more details.
      15  
      16  // Under Section 7 of GPL version 3, you are granted additional
      17  // permissions described in the GCC Runtime Library Exception, version
      18  // 3.1, as published by the Free Software Foundation.
      19  
      20  // You should have received a copy of the GNU General Public License and
      21  // a copy of the GCC Runtime Library Exception along with this program;
      22  // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
      23  // <http://www.gnu.org/licenses/>.
      24  
      25  #ifndef _GLIBCXX_ATOMIC_WORD_H
      26  #define _GLIBCXX_ATOMIC_WORD_H	1
      27  
      28  #ifdef __arch64__
      29    typedef long _Atomic_word;
      30  #else
      31    typedef int _Atomic_word;
      32  #endif
      33  
      34  #if defined(__sparc_v9__)
      35  // These are necessary under the V9 RMO model, though it is almost never
      36  // used in userspace.
      37  #define _GLIBCXX_READ_MEM_BARRIER \
      38    __asm __volatile ("membar #LoadLoad":::"memory")
      39  #define _GLIBCXX_WRITE_MEM_BARRIER \
      40    __asm __volatile ("membar #StoreStore":::"memory")
      41  
      42  #elif defined(__sparc_v8__)
      43  // This is necessary under the PSO model.
      44  #define _GLIBCXX_WRITE_MEM_BARRIER __asm __volatile ("stbar":::"memory")
      45  
      46  #endif
      47  
      48  #endif