sysdeps/sparc/atomic-machine.h

   1 /* Atomic operations.  Sparc version.
   2    Copyright (C) 2019-2022 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _ATOMIC_MACHINE_H
  20 #define _ATOMIC_MACHINE_H       1
  21
  22 #ifdef __arch64__
  23 # define __HAVE_64B_ATOMICS          1
  24 #else
  25 # define __HAVE_64B_ATOMICS          0
  26 #endif
  27 #define USE_ATOMIC_COMPILER_BUILTINS 1
  28
  29 /* XXX Is this actually correct?  */
  30 #define ATOMIC_EXCHANGE_USES_CAS     __HAVE_64B_ATOMICS
  31
  32 /* Compare and exchange.
  33    For all "bool" routines, we return FALSE if exchange succesful.  */
  34
  35 #define __arch_compare_and_exchange_val_int(mem, newval, oldval, model) \
  36   ({                                                                    \
  37     typeof (*mem) __oldval = (oldval);                                  \
  38     __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0,    \
  39                                  model, __ATOMIC_RELAXED);              \
  40     __oldval;                                                           \
  41   })
  42
  43 #define atomic_compare_and_exchange_val_acq(mem, new, old)                    \
  44   ({                                                                          \
  45     __typeof ((__typeof (*(mem))) *(mem)) __result;                           \
  46     if (sizeof (*mem) == 4                                                    \
  47         || (__HAVE_64B_ATOMICS && sizeof (*mem) == 8))                        \
  48       __result = __arch_compare_and_exchange_val_int (mem, new, old,          \
  49                                                          __ATOMIC_ACQUIRE);   \
  50     else                                                                      \
  51       abort ();                                                               \
  52     __result;                                                                 \
  53   })
  54
  55 #ifdef __sparc_v9__
  56 # define atomic_full_barrier() \
  57   __asm __volatile ("membar #LoadLoad | #LoadStore"                           \
  58                     " | #StoreLoad | #StoreStore" : : : "memory")
  59 # define atomic_read_barrier() \
  60   __asm __volatile ("membar #LoadLoad | #LoadStore" : : : "memory")
  61 # define atomic_write_barrier() \
  62   __asm __volatile ("membar #LoadStore | #StoreStore" : : : "memory")
  63
  64 extern void __cpu_relax (void);
  65 # define atomic_spin_nop() __cpu_relax ()
  66 #endif
  67
  68 #endif /* _ATOMIC_MACHINE_H  */