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/* Copyright (C) 2003-2024 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/>. */
/* Activate all C11 atomic builtins.
Note:
E.g. in nptl/pthread_key_delete.c if compiled with GCCs 6 and before,
an extra stack-frame is generated and the old value is stored on stack
before cs instruction but it never loads this value from stack.
An unreleased GCC 7 omit those stack operations.
E.g. in nptl/pthread_once.c the condition code of cs instruction is
evaluated by a sequence of ipm, sra, compare and jump instructions instead
of one conditional jump instruction. This also occurs with an unreleased
GCC 7.
The atomic_fetch_abc_def C11 builtins are now using load-and-abc instructions
on z196 zarch and higher cpus instead of a loop with compare-and-swap
instruction. */
#define USE_ATOMIC_COMPILER_BUILTINS 1
#ifdef __s390x__
# define __HAVE_64B_ATOMICS 1
#else
# define __HAVE_64B_ATOMICS 0
#endif
#define ATOMIC_EXCHANGE_USES_CAS 1
/* Implement some of the non-C11 atomic macros from include/atomic.h
with help of the C11 atomic builtins. The other non-C11 atomic macros
are using the macros defined here. */
/* Atomically store NEWVAL in *MEM if *MEM is equal to OLDVAL.
Return the old *MEM value. */
#define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \
({ __atomic_check_size((mem)); \
typeof ((__typeof (*(mem))) *(mem)) __atg1_oldval = (oldval); \
__atomic_compare_exchange_n (mem, (void *) &__atg1_oldval, \
newval, 1, __ATOMIC_ACQUIRE, \
__ATOMIC_RELAXED); \
__atg1_oldval; })
#define atomic_compare_and_exchange_val_rel(mem, newval, oldval) \
({ __atomic_check_size((mem)); \
typeof ((__typeof (*(mem))) *(mem)) __atg1_2_oldval = (oldval); \
__atomic_compare_exchange_n (mem, (void *) &__atg1_2_oldval, \
newval, 1, __ATOMIC_RELEASE, \
__ATOMIC_RELAXED); \
__atg1_2_oldval; })
/* Atomically store NEWVAL in *MEM if *MEM is equal to OLDVAL.
Return zero if *MEM was changed or non-zero if no exchange happened. */
#define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
({ __atomic_check_size((mem)); \
typeof ((__typeof (*(mem))) *(mem)) __atg2_oldval = (oldval); \
!__atomic_compare_exchange_n (mem, (void *) &__atg2_oldval, newval, \
1, __ATOMIC_ACQUIRE, \
__ATOMIC_RELAXED); })
#define catomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
atomic_compare_and_exchange_bool_acq (mem, newval, oldval)
/* Store NEWVALUE in *MEM and return the old value. */
#define atomic_exchange_acq(mem, newvalue) \
({ __atomic_check_size((mem)); \
__atomic_exchange_n (mem, newvalue, __ATOMIC_ACQUIRE); })
#define atomic_exchange_rel(mem, newvalue) \
({ __atomic_check_size((mem)); \
__atomic_exchange_n (mem, newvalue, __ATOMIC_RELEASE); })
/* Add VALUE to *MEM and return the old value of *MEM. */
/* The gcc builtin uses load-and-add instruction on z196 zarch and higher cpus
instead of a loop with compare-and-swap instruction. */
# define atomic_exchange_and_add_acq(mem, operand) \
({ __atomic_check_size((mem)); \
__atomic_fetch_add ((mem), (operand), __ATOMIC_ACQUIRE); })
# define atomic_exchange_and_add_rel(mem, operand) \
({ __atomic_check_size((mem)); \
__atomic_fetch_add ((mem), (operand), __ATOMIC_RELEASE); })
#define catomic_exchange_and_add(mem, value) \
atomic_exchange_and_add (mem, value)
/* Atomically *mem |= mask and return the old value of *mem. */
/* The gcc builtin uses load-and-or instruction on z196 zarch and higher cpus
instead of a loop with compare-and-swap instruction. */
#define atomic_or_val(mem, operand) \
({ __atomic_check_size((mem)); \
__atomic_fetch_or ((mem), (operand), __ATOMIC_ACQUIRE); })
/* Atomically *mem |= mask. */
#define atomic_or(mem, mask) \
do { \
atomic_or_val (mem, mask); \
} while (0)
#define catomic_or(mem, mask) \
atomic_or (mem, mask)
/* Atomically *mem |= 1 << bit and return true if the bit was set in old value
of *mem. */
/* The load-and-or instruction is used on z196 zarch and higher cpus
instead of a loop with compare-and-swap instruction. */
#define atomic_bit_test_set(mem, bit) \
({ __typeof (*(mem)) __atg14_old; \
__typeof (mem) __atg14_memp = (mem); \
__typeof (*(mem)) __atg14_mask = ((__typeof (*(mem))) 1 << (bit)); \
__atg14_old = atomic_or_val (__atg14_memp, __atg14_mask); \
__atg14_old & __atg14_mask; })
/* Atomically *mem &= mask and return the old value of *mem. */
/* The gcc builtin uses load-and-and instruction on z196 zarch and higher cpus
instead of a loop with compare-and-swap instruction. */
#define atomic_and_val(mem, operand) \
({ __atomic_check_size((mem)); \
__atomic_fetch_and ((mem), (operand), __ATOMIC_ACQUIRE); })
/* Atomically *mem &= mask. */
#define atomic_and(mem, mask) \
do { \
atomic_and_val (mem, mask); \
} while (0)
#define catomic_and(mem, mask) \
atomic_and(mem, mask)
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