glibc/sysdeps/powerpc/atomic-machine.h

61 lines
1.9 KiB
C

/* Atomic operations. PowerPC Common version.
Copyright (C) 2003-2025 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#ifndef _POWERPC_ATOMIC_MACHINE_H
#define _POWERPC_ATOMIC_MACHINE_H 1
#if __WORDSIZE == 64
# define __HAVE_64B_ATOMICS 1
#else
# define __HAVE_64B_ATOMICS 0
#endif
#define ATOMIC_EXCHANGE_USES_CAS 1
/* Used on pthread_spin_{try}lock. */
#define __ARCH_ACQ_INSTR "isync"
#if defined _ARCH_PWR6 || defined _ARCH_PWR6X
# define MUTEX_HINT_ACQ ",1"
# define MUTEX_HINT_REL ",0"
#else
# define MUTEX_HINT_ACQ
# define MUTEX_HINT_REL
#endif
#ifdef _ARCH_PWR4
/*
* Newer powerpc64 processors support the new "light weight" sync (lwsync)
* So if the build is using -mcpu=[power4,power5,power5+,970] we can
* safely use lwsync.
*/
# define atomic_read_barrier() __asm ("lwsync" ::: "memory")
/*
* "light weight" sync can also be used for the release barrier.
*/
# define atomic_write_barrier() __asm ("lwsync" ::: "memory")
#else
/*
* Older powerpc32 processors don't support the new "light weight"
* sync (lwsync). So the only safe option is to use normal sync
* for all powerpc32 applications.
*/
# define atomic_read_barrier() __asm ("sync" ::: "memory")
# define atomic_write_barrier() __asm ("sync" ::: "memory")
#endif
#endif