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/* RSEQ_* accessors. Generic version.
Copyright (C) 2002-2025 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/>. */
#include <atomic.h>
/* Read member of the RSEQ area directly. */
#define RSEQ_GETMEM(member) \
RSEQ_SELF()->member
/* Set member of the RSEQ area directly. */
#define RSEQ_SETMEM(member, value) \
RSEQ_SELF()->member = (value)
/* Static assert for types that can't be loaded/stored atomically on the
current architecture. */
#if __HAVE_64B_ATOMICS
#define __RSEQ_ASSERT_ATOMIC(member) \
_Static_assert (sizeof (RSEQ_SELF()->member) == 1 \
|| sizeof (RSEQ_SELF()->member) == 4 \
|| sizeof (RSEQ_SELF()->member) == 8, \
"size of rseq data")
#else
#define __RSEQ_ASSERT_ATOMIC(member) \
_Static_assert (sizeof (RSEQ_SELF()->member) == 1 \
|| sizeof (RSEQ_SELF()->member) == 4, \
"size of rseq data")
#endif
/* Read member of the RSEQ area directly, with single-copy atomicity semantics. */
#define RSEQ_GETMEM_ONCE(member) \
({ \
__RSEQ_ASSERT_ATOMIC(member); \
(*(volatile __typeof (RSEQ_SELF()->member) *)&RSEQ_SELF()->member); \
})
/* Set member of the RSEQ area directly, with single-copy atomicity semantics. */
#define RSEQ_SETMEM_ONCE(member, value) \
({ \
__RSEQ_ASSERT_ATOMIC(member); \
(*(volatile __typeof (RSEQ_SELF()->member) *)&RSEQ_SELF()->member = (value)); \
})
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