libitm/config/linux/x86/futex_bits.h

   1 /* Copyright (C) 2008-2016 Free Software Foundation, Inc.
   2    Contributed by Richard Henderson <rth@redhat.com>.
   3
   4    This file is part of the GNU Transactional Memory Library (libitm).
   5
   6    Libitm is free software; you can redistribute it and/or modify it
   7    under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    Libitm is distributed in the hope that it will be useful, but WITHOUT ANY
  12    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  13    FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14    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 #ifdef __x86_64__
  26 # ifndef SYS_futex
  27 #  define SYS_futex     202
  28 # endif
  29
  30 static inline long
  31 sys_futex0 (std::atomic<int> *addr, int op, int val)
  32 {
  33   long res;
  34
  35   register long r10 __asm__("%r10") = 0;
  36   __asm volatile ("syscall"
  37                   : "=a" (res)
  38                   : "0" (SYS_futex), "D" (addr), "S" (op),
  39                     "d" (val), "r" (r10)
  40                   : "r11", "rcx", "memory");
  41
  42   return res;
  43 }
  44
  45 #else
  46 # ifndef SYS_futex
  47 #  define SYS_futex     240
  48 # endif
  49
  50 static inline long
  51 sys_futex0 (std::atomic<int> *addr, int op, int val)
  52 {
  53   long res;
  54
  55   __asm volatile ("int $0x80"
  56                   : "=a" (res)
  57                   : "0"(SYS_futex), "b" (addr), "c"(op),
  58                     "d"(val), "S"(0)
  59                   : "memory");
  60   return res;
  61 }
  62
  63 #endif /* __x86_64__ */