text: /* Copyright (C) 2005, 2008, 2009 Free Software Foundation, Inc.
     Contributed by Jakub Jelinek <jakub@redhat.com>.
  
     This file is part of the GNU OpenMP Library (libgomp).
  
     Libgomp is free software; you can redistribute it and/or modify it
     under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 3, or (at your option)
     any later version.
  
     Libgomp 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.
  
     Under Section 7 of GPL version 3, you are granted additional
     permissions described in the GCC Runtime Library Exception, version
     3.1, as published by the Free Software Foundation.
  
     You should have received a copy of the GNU General Public License and
     a copy of the GCC Runtime Library Exception along with this program;
     see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
     <http://www.gnu.org/licenses/>.  */
  
  /* Provide target-specific access to the futex system call.  */
  
  #include <sys/syscall.h>
  
  static inline long
  sys_futex0 (int *addr, int op, int val)
  {
    register long int gpr2  __asm__ ("2");
    register long int gpr3  __asm__ ("3");
    register long int gpr4  __asm__ ("4");
    register long int gpr5  __asm__ ("5");
  
    gpr2 = (long) addr;
    gpr3 = op;
    gpr4 = val;
    gpr5 = 0;
  
    __asm volatile ("svc %b1"
  		  : "=d" (gpr2)
  		  : "i" (SYS_futex),
  		    "0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5)
  		  : "memory");
    return gpr2;
  }
  
  static inline void
  futex_wait (int *addr, int val)
  {
    long err = sys_futex0 (addr, gomp_futex_wait, val);
    if (__builtin_expect (err == -ENOSYS, 0))
      {
        gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
        gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
        sys_futex0 (addr, gomp_futex_wait, val);
      }
  }
  
  static inline void
  futex_wake (int *addr, int count)
  {
    long err = sys_futex0 (addr, gomp_futex_wake, count);
    if (__builtin_expect (err == -ENOSYS, 0))
      {
        gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
        gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
        sys_futex0 (addr, gomp_futex_wake, count);
      }
  }
  
  static inline void
  cpu_relax (void)
  {
    __asm volatile ("" : : : "memory");
  }
  
  static inline void
  atomic_write_barrier (void)
  {
    __sync_synchronize ();
  }
  