sysdeps/mips/sys/tas.h

   1 /* Copyright (C) 2000, 2002, 2003, 2004, 2007, 2009
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Maciej W. Rozycki <macro@ds2.pg.gda.pl>, 2000.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C 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 GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library.  If not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef _SYS_TAS_H
  21 #define _SYS_TAS_H 1
  22
  23 #include <features.h>
  24 #include <sgidefs.h>
  25
  26 __BEGIN_DECLS
  27
  28 extern int _test_and_set (int *__p, int __v) __THROW;
  29
  30 #ifdef __USE_EXTERN_INLINES
  31
  32 # ifndef _EXTERN_INLINE
  33 #  define _EXTERN_INLINE __extern_inline
  34 # endif
  35
  36 _EXTERN_INLINE int
  37 __NTH (_test_and_set (int *__p, int __v))
  38 {
  39   int __r, __t;
  40
  41   __asm__ __volatile__
  42     ("/* Inline test and set */\n"
  43      ".set      push\n\t"
  44 #if _MIPS_SIM == _ABIO32
  45      ".set      mips2\n\t"
  46 #endif
  47      "sync\n\t"
  48      "1:\n\t"
  49      "ll        %0,%3\n\t"
  50      "move      %1,%4\n\t"
  51      "beq       %0,%4,2f\n\t"
  52      "sc        %1,%2\n\t"
  53      "beqz      %1,1b\n"
  54      "sync\n\t"
  55      ".set      pop\n\t"
  56      "2:\n\t"
  57      "/* End test and set */"
  58      : "=&r" (__r), "=&r" (__t), "=m" (*__p)
  59      : "m" (*__p), "r" (__v)
  60      : "memory");
  61
  62   return __r;
  63 }
  64
  65 #endif /* __USE_EXTERN_INLINES */
  66
  67 __END_DECLS
  68
  69 #endif /* sys/tas.h */