glibc/sysdeps/arc/atomic-machine.h
Paul Eggert 581c785bf3 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.

I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah.  I don't
know why I run into these diagnostics whereas others evidently do not.

remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2022-01-01 11:40:24 -08:00

58 lines
2.4 KiB
C

/* Low-level functions for atomic operations. ARC version.
Copyright (C) 2020-2022 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 _ARC_BITS_ATOMIC_H
#define _ARC_BITS_ATOMIC_H 1
#define __HAVE_64B_ATOMICS 0
#define USE_ATOMIC_COMPILER_BUILTINS 1
/* ARC does have legacy atomic EX reg, [mem] instruction but the micro-arch
is not as optimal as LLOCK/SCOND specially for SMP. */
#define ATOMIC_EXCHANGE_USES_CAS 1
#define __arch_compare_and_exchange_bool_8_acq(mem, newval, oldval) \
(abort (), 0)
#define __arch_compare_and_exchange_bool_16_acq(mem, newval, oldval) \
(abort (), 0)
#define __arch_compare_and_exchange_bool_64_acq(mem, newval, oldval) \
(abort (), 0)
#define __arch_compare_and_exchange_val_8_int(mem, newval, oldval, model) \
(abort (), (__typeof (*mem)) 0)
#define __arch_compare_and_exchange_val_16_int(mem, newval, oldval, model) \
(abort (), (__typeof (*mem)) 0)
#define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
(abort (), (__typeof (*mem)) 0)
#define __arch_compare_and_exchange_val_32_int(mem, newval, oldval, model) \
({ \
typeof (*mem) __oldval = (oldval); \
__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, \
model, __ATOMIC_RELAXED); \
__oldval; \
})
#define atomic_compare_and_exchange_val_acq(mem, new, old) \
__atomic_val_bysize (__arch_compare_and_exchange_val, int, \
mem, new, old, __ATOMIC_ACQUIRE)
#define atomic_full_barrier() ({ asm volatile ("dmb 3":::"memory"); })
#endif /* _ARC_BITS_ATOMIC_H */