glibc/sysdeps/mips/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

185 lines
6.1 KiB
C

/* Low-level functions for atomic operations. Mips version.
Copyright (C) 2005-2022 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 _MIPS_ATOMIC_MACHINE_H
#define _MIPS_ATOMIC_MACHINE_H 1
#include <sgidefs.h>
#if _MIPS_SIM == _ABIO32 && __mips < 2
#define MIPS_PUSH_MIPS2 ".set mips2\n\t"
#else
#define MIPS_PUSH_MIPS2
#endif
#if _MIPS_SIM == _ABIO32 || _MIPS_SIM == _ABIN32
#define __HAVE_64B_ATOMICS 0
#else
#define __HAVE_64B_ATOMICS 1
#endif
/* See the comments in <sys/asm.h> about the use of the sync instruction. */
#ifndef MIPS_SYNC
# define MIPS_SYNC sync
#endif
#define MIPS_SYNC_STR_2(X) #X
#define MIPS_SYNC_STR_1(X) MIPS_SYNC_STR_2(X)
#define MIPS_SYNC_STR MIPS_SYNC_STR_1(MIPS_SYNC)
#define USE_ATOMIC_COMPILER_BUILTINS 1
/* MIPS is an LL/SC machine. However, XLP has a direct atomic exchange
instruction which will be used by __atomic_exchange_n. */
#ifdef _MIPS_ARCH_XLP
# define ATOMIC_EXCHANGE_USES_CAS 0
#else
# define ATOMIC_EXCHANGE_USES_CAS 1
#endif
/* Compare and exchange.
For all "bool" routines, we return FALSE if exchange succesful. */
#define __arch_compare_and_exchange_bool_8_int(mem, newval, oldval, model) \
(abort (), 0)
#define __arch_compare_and_exchange_bool_16_int(mem, newval, oldval, model) \
(abort (), 0)
#define __arch_compare_and_exchange_bool_32_int(mem, newval, oldval, model) \
({ \
typeof (*mem) __oldval = (oldval); \
!__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, \
model, __ATOMIC_RELAXED); \
})
#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_32_int(mem, newval, oldval, model) \
({ \
typeof (*mem) __oldval = (oldval); \
__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, \
model, __ATOMIC_RELAXED); \
__oldval; \
})
#if _MIPS_SIM == _ABIO32
/* We can't do an atomic 64-bit operation in O32. */
# define __arch_compare_and_exchange_bool_64_int(mem, newval, oldval, model) \
(abort (), 0)
# define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
(abort (), (typeof(*mem)) 0)
#else
# define __arch_compare_and_exchange_bool_64_int(mem, newval, oldval, model) \
__arch_compare_and_exchange_bool_32_int (mem, newval, oldval, model)
# define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
__arch_compare_and_exchange_val_32_int (mem, newval, oldval, model)
#endif
/* Compare and exchange with "acquire" semantics, ie barrier after. */
#define atomic_compare_and_exchange_bool_acq(mem, new, old) \
__atomic_bool_bysize (__arch_compare_and_exchange_bool, int, \
mem, new, old, __ATOMIC_ACQUIRE)
#define atomic_compare_and_exchange_val_acq(mem, new, old) \
__atomic_val_bysize (__arch_compare_and_exchange_val, int, \
mem, new, old, __ATOMIC_ACQUIRE)
/* Compare and exchange with "release" semantics, ie barrier before. */
#define atomic_compare_and_exchange_val_rel(mem, new, old) \
__atomic_val_bysize (__arch_compare_and_exchange_val, int, \
mem, new, old, __ATOMIC_RELEASE)
/* Atomic exchange (without compare). */
#define __arch_exchange_8_int(mem, newval, model) \
(abort (), (typeof(*mem)) 0)
#define __arch_exchange_16_int(mem, newval, model) \
(abort (), (typeof(*mem)) 0)
#define __arch_exchange_32_int(mem, newval, model) \
__atomic_exchange_n (mem, newval, model)
#if _MIPS_SIM == _ABIO32
/* We can't do an atomic 64-bit operation in O32. */
# define __arch_exchange_64_int(mem, newval, model) \
(abort (), (typeof(*mem)) 0)
#else
# define __arch_exchange_64_int(mem, newval, model) \
__atomic_exchange_n (mem, newval, model)
#endif
#define atomic_exchange_acq(mem, value) \
__atomic_val_bysize (__arch_exchange, int, mem, value, __ATOMIC_ACQUIRE)
#define atomic_exchange_rel(mem, value) \
__atomic_val_bysize (__arch_exchange, int, mem, value, __ATOMIC_RELEASE)
/* Atomically add value and return the previous (unincremented) value. */
#define __arch_exchange_and_add_8_int(mem, value, model) \
(abort (), (typeof(*mem)) 0)
#define __arch_exchange_and_add_16_int(mem, value, model) \
(abort (), (typeof(*mem)) 0)
#define __arch_exchange_and_add_32_int(mem, value, model) \
__atomic_fetch_add (mem, value, model)
#if _MIPS_SIM == _ABIO32
/* We can't do an atomic 64-bit operation in O32. */
# define __arch_exchange_and_add_64_int(mem, value, model) \
(abort (), (typeof(*mem)) 0)
#else
# define __arch_exchange_and_add_64_int(mem, value, model) \
__atomic_fetch_add (mem, value, model)
#endif
#define atomic_exchange_and_add_acq(mem, value) \
__atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \
__ATOMIC_ACQUIRE)
#define atomic_exchange_and_add_rel(mem, value) \
__atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \
__ATOMIC_RELEASE)
/* TODO: More atomic operations could be implemented efficiently; only the
basic requirements are done. */
#ifdef __mips16
# define atomic_full_barrier() __sync_synchronize ()
#else /* !__mips16 */
# define atomic_full_barrier() \
__asm__ __volatile__ (".set push\n\t" \
MIPS_PUSH_MIPS2 \
MIPS_SYNC_STR "\n\t" \
".set pop" : : : "memory")
#endif /* !__mips16 */
#endif /* atomic-machine.h */