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

   1 // Low-level functions for atomic operations: Sparc version  -*- C++ -*-
   2
   3 // Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2009
   4 // Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // Under Section 7 of GPL version 3, you are granted additional
  18 // permissions described in the GCC Runtime Library Exception, version
  19 // 3.1, as published by the Free Software Foundation.
  20
  21 // You should have received a copy of the GNU General Public License and
  22 // a copy of the GCC Runtime Library Exception along with this program;
  23 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24 // <http://www.gnu.org/licenses/>.
  25
  26 #include <ext/atomicity.h>
  27
  28 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
  29
  30 #ifdef __arch64__
  31   _Atomic_word
  32   __attribute__ ((__unused__))
  33   __exchange_and_add(volatile _Atomic_word* __mem, int __val) throw ()
  34   {
  35     _Atomic_word __tmp1, __tmp2;
  36     _Atomic_word __val_extended = __val;
  37
  38     __asm__ __volatile__("1:    ldx     [%3], %0\n\t"
  39                          "      add     %0, %4, %1\n\t"
  40                          "      casx    [%3], %0, %1\n\t"
  41                          "      sub     %0, %1, %0\n\t"
  42                          "      brnz,pn %0, 1b\n\t"
  43                          "       nop"
  44                          : "=&r" (__tmp1), "=&r" (__tmp2), "=m" (*__mem)
  45                          : "r" (__mem), "r" (__val_extended), "m" (*__mem));
  46     return __tmp2;
  47   }
  48
  49   void
  50   __attribute__ ((__unused__))
  51   __atomic_add(volatile _Atomic_word* __mem, int __val) throw ()
  52   {
  53     _Atomic_word __tmp1, __tmp2;
  54     _Atomic_word __val_extended = __val;
  55
  56     __asm__ __volatile__("1:    ldx     [%3], %0\n\t"
  57                          "      add     %0, %4, %1\n\t"
  58                          "      casx    [%3], %0, %1\n\t"
  59                          "      sub     %0, %1, %0\n\t"
  60                          "      brnz,pn %0, 1b\n\t"
  61                          "       nop"
  62                          : "=&r" (__tmp1), "=&r" (__tmp2), "=m" (*__mem)
  63                          : "r" (__mem), "r" (__val_extended), "m" (*__mem));
  64   }
  65
  66 #else /* __arch32__ */
  67
  68   template<int __inst>
  69     struct _Atomicity_lock
  70     {
  71       static unsigned char _S_atomicity_lock;
  72     };
  73
  74   template<int __inst>
  75   unsigned char _Atomicity_lock<__inst>::_S_atomicity_lock = 0;
  76
  77   template unsigned char _Atomicity_lock<0>::_S_atomicity_lock;
  78
  79   _Atomic_word
  80   __attribute__ ((__unused__))
  81   __exchange_and_add(volatile _Atomic_word* __mem, int __val) throw ()
  82   {
  83     _Atomic_word __result, __tmp;
  84
  85     __asm__ __volatile__("1:    ldstub  [%1], %0\n\t"
  86                          "      cmp     %0, 0\n\t"
  87                          "      bne     1b\n\t"
  88                          "       nop"
  89                          : "=&r" (__tmp)
  90                          : "r" (&_Atomicity_lock<0>::_S_atomicity_lock)
  91                          : "memory");
  92     __result = *__mem;
  93     *__mem += __val;
  94     __asm__ __volatile__("stb   %%g0, [%0]"
  95                          : /* no outputs */
  96                          : "r" (&_Atomicity_lock<0>::_S_atomicity_lock)
  97                          : "memory");
  98     return __result;
  99   }
 100
 101   void
 102   __attribute__ ((__unused__))
 103   __atomic_add(volatile _Atomic_word* __mem, int __val) throw ()
 104   {
 105     _Atomic_word __tmp;
 106
 107     __asm__ __volatile__("1:    ldstub  [%1], %0\n\t"
 108                          "      cmp     %0, 0\n\t"
 109                          "      bne     1b\n\t"
 110                          "       nop"
 111                          : "=&r" (__tmp)
 112                          : "r" (&_Atomicity_lock<0>::_S_atomicity_lock)
 113                          : "memory");
 114     *__mem += __val;
 115     __asm__ __volatile__("stb   %%g0, [%0]"
 116                          : /* no outputs */
 117                          : "r" (&_Atomicity_lock<0>::_S_atomicity_lock)
 118                          : "memory");
 119   }
 120 #endif /* __arch32__ */
 121
 122 _GLIBCXX_END_NAMESPACE