libstdc++-v3/config/cpu/mips/atomicity.h

   1 // Low-level functions for atomic operations.
   2
   3 // Copyright (C) 2001, 2002, 2003 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 2, 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 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING.  If not, write to the Free
  18 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  19 // USA.
  20
  21 // As a special exception, you may use this file as part of a free software
  22 // library without restriction.  Specifically, if other files instantiate
  23 // templates or use macros or inline functions from this file, or you compile
  24 // this file and link it with other files to produce an executable, this
  25 // file does not by itself cause the resulting executable to be covered by
  26 // the GNU General Public License.  This exception does not however
  27 // invalidate any other reasons why the executable file might be covered by
  28 // the GNU General Public License.
  29
  30 #ifndef _GLIBCXX_ATOMICITY_H
  31 #define _GLIBCXX_ATOMICITY_H 1
  32
  33 typedef int _Atomic_word;
  34
  35 static inline int
  36 __attribute__ ((__unused__))
  37 __exchange_and_add(volatile _Atomic_word* __mem, int __val)
  38 {
  39   int __result, __tmp;
  40
  41   __asm__ __volatile__
  42     ("/* Inline exchange & add */\n\t"
  43      "1:\n\t"
  44      ".set      push\n\t"
  45 #if _MIPS_SIM == _ABIO32
  46      ".set      mips2\n\t"
  47 #endif
  48      "ll        %0,%3\n\t"
  49      "addu      %1,%4,%0\n\t"
  50      "sc        %1,%2\n\t"
  51      ".set      pop\n\t"
  52      "beqz      %1,1b\n\t"
  53      "/* End exchange & add */"
  54      : "=&r"(__result), "=&r"(__tmp), "=m"(*__mem)
  55      : "m" (*__mem), "r"(__val)
  56      : "memory");
  57
  58   return __result;
  59 }
  60
  61 static inline void
  62 __attribute__ ((__unused__))
  63 __atomic_add(volatile _Atomic_word* __mem, int __val)
  64 {
  65   int __result;
  66
  67   __asm__ __volatile__
  68     ("/* Inline atomic add */\n\t"
  69      "1:\n\t"
  70      ".set      push\n\t"
  71 #if _MIPS_SIM == _ABIO32
  72      ".set      mips2\n\t"
  73 #endif
  74      "ll        %0,%2\n\t"
  75      "addu      %0,%3,%0\n\t"
  76      "sc        %0,%1\n\t"
  77      ".set      pop\n\t"
  78      "beqz      %0,1b\n\t"
  79      "/* End atomic add */"
  80      : "=&r"(__result), "=m"(*__mem)
  81      : "m" (*__mem), "r"(__val)
  82      : "memory");
  83 }
  84
  85 #endif /* atomicity.h */