542 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C++
		
	
	
			
		
		
	
	
			542 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C++
		
	
	
// Source: https://android.googlesource.com/platform/bionic/+/lollipop-release/libc/include/stdatomic.h
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/*-
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 * Copyright (c) 2011 Ed Schouten <ed@FreeBSD.org>
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 *                    David Chisnall <theraven@FreeBSD.org>
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 * All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 *
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 * $FreeBSD$
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 */
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#ifndef _STDATOMIC_H_
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#define _STDATOMIC_H_
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#include <sys/cdefs.h>
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#if defined(__cplusplus) && defined(_USING_LIBCXX)
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#ifdef __clang__
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#if __has_feature(cxx_atomic)
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#define _STDATOMIC_HAVE_ATOMIC
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#endif
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#else /* gcc */
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#if __GNUC_PREREQ(4, 7)
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#define _STDATOMIC_HAVE_ATOMIC
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#endif
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#endif
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#endif
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#ifdef _STDATOMIC_HAVE_ATOMIC
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/* We have a usable C++ <atomic>; use it instead.  */
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#include <atomic>
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#undef _Atomic
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/* Also defined by <atomic> for gcc.  But not used in macros. */
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/* Also a clang intrinsic.                                    */
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/* Should not be used by client code before this file is      */
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/* included.  The definitions in <atomic> themselves see      */
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/* the old definition, as they should.                        */
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/* Client code sees the following definition.                 */
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#define _Atomic(t) std::atomic<t>
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using std::atomic_bool;
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using std::atomic_char;
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using std::atomic_char16_t;
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using std::atomic_char32_t;
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using std::atomic_compare_exchange_strong;
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using std::atomic_compare_exchange_strong_explicit;
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using std::atomic_compare_exchange_weak;
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using std::atomic_compare_exchange_weak_explicit;
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using std::atomic_exchange;
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using std::atomic_exchange_explicit;
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using std::atomic_fetch_add;
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using std::atomic_fetch_add_explicit;
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using std::atomic_fetch_and;
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using std::atomic_fetch_and_explicit;
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using std::atomic_fetch_or;
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using std::atomic_fetch_or_explicit;
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using std::atomic_fetch_sub;
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using std::atomic_fetch_sub_explicit;
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using std::atomic_fetch_xor;
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using std::atomic_fetch_xor_explicit;
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using std::atomic_init;
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using std::atomic_int;
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using std::atomic_int_fast16_t;
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using std::atomic_int_fast32_t;
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using std::atomic_int_fast64_t;
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using std::atomic_int_fast8_t;
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using std::atomic_int_least16_t;
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using std::atomic_int_least32_t;
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using std::atomic_int_least64_t;
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using std::atomic_int_least8_t;
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using std::atomic_intmax_t;
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using std::atomic_intptr_t;
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using std::atomic_is_lock_free;
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using std::atomic_llong;
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using std::atomic_load;
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using std::atomic_load_explicit;
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using std::atomic_long;
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using std::atomic_ptrdiff_t;
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using std::atomic_schar;
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using std::atomic_short;
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using std::atomic_signal_fence;
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using std::atomic_size_t;
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using std::atomic_store;
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using std::atomic_store_explicit;
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using std::atomic_thread_fence;
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using std::atomic_uchar;
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using std::atomic_uint;
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using std::atomic_uint_fast16_t;
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using std::atomic_uint_fast32_t;
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using std::atomic_uint_fast64_t;
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using std::atomic_uint_fast8_t;
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using std::atomic_uint_least16_t;
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using std::atomic_uint_least32_t;
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using std::atomic_uint_least64_t;
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using std::atomic_uint_least8_t;
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using std::atomic_uintmax_t;
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using std::atomic_uintptr_t;
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using std::atomic_ullong;
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using std::atomic_ulong;
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using std::atomic_ushort;
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using std::atomic_wchar_t;
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using std::memory_order;
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using std::memory_order_acq_rel;
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using std::memory_order_consume;
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using std::memory_order_relaxed;
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using std::memory_order_release;
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using std::memory_order_seq_cst;
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#else /* <atomic> unavailable, possibly because this is C, not C++ */
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#include <sys/types.h>
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#include <stdbool.h>
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/*
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 * C: Do it ourselves.
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 * Note that the runtime representation defined here should be compatible
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 * with the C++ one, i.e. an _Atomic(T) needs to contain the same
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 * bits as a T.
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 */
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#include <stddef.h> /* For ptrdiff_t.                          */
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#include <stdint.h> /* TODO: Should pollute namespace less.    */
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#if __STDC_VERSION__ >= 201112L
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#include <uchar.h> /* For char16_t and char32_t.              */
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#endif
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#ifdef __clang__
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#if __has_extension(c_atomic) || __has_extension(cxx_atomic)
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#define __CLANG_ATOMICS
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#else
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#error "stdatomic.h does not support your compiler"
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#endif
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#if __has_builtin(__sync_swap)
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#define __HAS_BUILTIN_SYNC_SWAP
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#endif
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#else
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#if __GNUC_PREREQ(4, 7)
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#define __GNUC_ATOMICS
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#else
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#define __SYNC_ATOMICS
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#ifdef __cplusplus
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#define __ATOMICS_AVOID_DOT_INIT
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#endif
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#endif
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#endif
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/*
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 * 7.17.1 Atomic lock-free macros.
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 */
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#ifdef __GCC_ATOMIC_BOOL_LOCK_FREE
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#define ATOMIC_BOOL_LOCK_FREE __GCC_ATOMIC_BOOL_LOCK_FREE
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#elif defined(__SYNC_ATOMICS)
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#define ATOMIC_BOOL_LOCK_FREE 2 /* For all modern platforms */
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#endif
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#ifdef __GCC_ATOMIC_CHAR_LOCK_FREE
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#define ATOMIC_CHAR_LOCK_FREE __GCC_ATOMIC_CHAR_LOCK_FREE
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#elif defined(__SYNC_ATOMICS)
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#define ATOMIC_CHAR_LOCK_FREE 2
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#endif
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#ifdef __GCC_ATOMIC_CHAR16_T_LOCK_FREE
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#define ATOMIC_CHAR16_T_LOCK_FREE __GCC_ATOMIC_CHAR16_T_LOCK_FREE
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#elif defined(__SYNC_ATOMICS)
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#define ATOMIC_CHAR16_T_LOCK_FREE 2
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#endif
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#ifdef __GCC_ATOMIC_CHAR32_T_LOCK_FREE
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#define ATOMIC_CHAR32_T_LOCK_FREE __GCC_ATOMIC_CHAR32_T_LOCK_FREE
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#elif defined(__SYNC_ATOMICS)
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#define ATOMIC_CHAR32_T_LOCK_FREE 2
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#endif
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#ifdef __GCC_ATOMIC_WCHAR_T_LOCK_FREE
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#define ATOMIC_WCHAR_T_LOCK_FREE __GCC_ATOMIC_WCHAR_T_LOCK_FREE
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#elif defined(__SYNC_ATOMICS)
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#define ATOMIC_WCHAR_T_LOCK_FREE 2
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#endif
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#ifdef __GCC_ATOMIC_SHORT_LOCK_FREE
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#define ATOMIC_SHORT_LOCK_FREE __GCC_ATOMIC_SHORT_LOCK_FREE
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#elif defined(__SYNC_ATOMICS)
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#define ATOMIC_SHORT_LOCK_FREE 2
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#endif
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#ifdef __GCC_ATOMIC_INT_LOCK_FREE
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#define ATOMIC_INT_LOCK_FREE __GCC_ATOMIC_INT_LOCK_FREE
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#elif defined(__SYNC_ATOMICS)
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#define ATOMIC_INT_LOCK_FREE 2
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#endif
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#ifdef __GCC_ATOMIC_LONG_LOCK_FREE
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#define ATOMIC_LONG_LOCK_FREE __GCC_ATOMIC_LONG_LOCK_FREE
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#elif defined(__SYNC_ATOMICS)
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#define ATOMIC_LONG_LOCK_FREE 2
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#endif
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#ifdef __GCC_ATOMIC_LLONG_LOCK_FREE
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#define ATOMIC_LLONG_LOCK_FREE __GCC_ATOMIC_LLONG_LOCK_FREE
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#elif defined(__SYNC_ATOMICS)
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#define ATOMIC_LLONG_LOCK_FREE 1 /* maybe */
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#endif
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#ifdef __GCC_ATOMIC_POINTER_LOCK_FREE
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#define ATOMIC_POINTER_LOCK_FREE __GCC_ATOMIC_POINTER_LOCK_FREE
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#elif defined(__SYNC_ATOMICS)
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#define ATOMIC_POINTER_LOCK_FREE 2
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#endif
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/*
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 * 7.17.2 Initialization.
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 */
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#if defined(__CLANG_ATOMICS)
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#define ATOMIC_VAR_INIT(value) (value)
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#define atomic_init(obj, value) __c11_atomic_init(obj, value)
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#else
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#ifdef __ATOMICS_AVOID_DOT_INIT
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#define ATOMIC_VAR_INIT(value) \
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    {                          \
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        value                  \
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    }
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#else
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#define ATOMIC_VAR_INIT(value) \
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    {                          \
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        .__val = (value)       \
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    }
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#endif
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#define atomic_init(obj, value) ((void)((obj)->__val = (value)))
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#endif
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/*
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 * Clang and recent GCC both provide predefined macros for the memory
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 * orderings.  If we are using a compiler that doesn't define them, use the
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 * clang values - these will be ignored in the fallback path.
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 */
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#ifndef __ATOMIC_RELAXED
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#define __ATOMIC_RELAXED 0
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#endif
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#ifndef __ATOMIC_CONSUME
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#define __ATOMIC_CONSUME 1
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#endif
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#ifndef __ATOMIC_ACQUIRE
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#define __ATOMIC_ACQUIRE 2
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#endif
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#ifndef __ATOMIC_RELEASE
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#define __ATOMIC_RELEASE 3
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#endif
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#ifndef __ATOMIC_ACQ_REL
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#define __ATOMIC_ACQ_REL 4
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#endif
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#ifndef __ATOMIC_SEQ_CST
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#define __ATOMIC_SEQ_CST 5
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#endif
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/*
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 * 7.17.3 Order and consistency.
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 *
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 * The memory_order_* constants that denote the barrier behaviour of the
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 * atomic operations.
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 * The enum values must be identical to those used by the
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 * C++ <atomic> header.
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 */
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typedef enum
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{
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    memory_order_relaxed = __ATOMIC_RELAXED,
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    memory_order_consume = __ATOMIC_CONSUME,
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    memory_order_acquire = __ATOMIC_ACQUIRE,
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    memory_order_release = __ATOMIC_RELEASE,
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    memory_order_acq_rel = __ATOMIC_ACQ_REL,
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    memory_order_seq_cst = __ATOMIC_SEQ_CST
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} memory_order;
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/*
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 * 7.17.4 Fences.
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 */
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static __inline void
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atomic_thread_fence(memory_order __order __attribute__((unused)))
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{
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#ifdef __CLANG_ATOMICS
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    __c11_atomic_thread_fence(__order);
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#elif defined(__GNUC_ATOMICS)
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    __atomic_thread_fence(__order);
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#else
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    __sync_synchronize();
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#endif
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}
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static __inline void
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atomic_signal_fence(memory_order __order __attribute__((unused)))
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{
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#ifdef __CLANG_ATOMICS
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    __c11_atomic_signal_fence(__order);
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#elif defined(__GNUC_ATOMICS)
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    __atomic_signal_fence(__order);
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#else
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    __asm volatile("" ::
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                       : "memory");
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#endif
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}
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/*
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 * 7.17.5 Lock-free property.
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 */
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#if defined(_KERNEL)
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/* Atomics in kernelspace are always lock-free. */
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#define atomic_is_lock_free(obj) \
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    ((void)(obj), (_Bool)1)
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#elif defined(__CLANG_ATOMICS)
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#define atomic_is_lock_free(obj) \
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    __c11_atomic_is_lock_free(sizeof(*(obj)))
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#elif defined(__GNUC_ATOMICS)
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#define atomic_is_lock_free(obj) \
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    __atomic_is_lock_free(sizeof((obj)->__val), &(obj)->__val)
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#else
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#define atomic_is_lock_free(obj) \
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    ((void)(obj), sizeof((obj)->__val) <= sizeof(void *))
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#endif
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/*
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 * 7.17.6 Atomic integer types.
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 */
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#ifndef __CLANG_ATOMICS
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/*
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 * No native support for _Atomic(). Place object in structure to prevent
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 * most forms of direct non-atomic access.
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 */
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#define _Atomic(T)        \
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    struct                \
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    {                     \
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        T volatile __val; \
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    }
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#endif
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typedef _Atomic(bool) atomic_bool;
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typedef _Atomic(char) atomic_char;
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typedef _Atomic(signed char) atomic_schar;
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typedef _Atomic(unsigned char) atomic_uchar;
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typedef _Atomic(short) atomic_short;
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typedef _Atomic(unsigned short) atomic_ushort;
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typedef _Atomic(int) atomic_int;
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typedef _Atomic(unsigned int) atomic_uint;
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typedef _Atomic(long) atomic_long;
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typedef _Atomic(unsigned long) atomic_ulong;
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typedef _Atomic(long long) atomic_llong;
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typedef _Atomic(unsigned long long) atomic_ullong;
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#if __STDC_VERSION__ >= 201112L || __cplusplus >= 201103L
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typedef _Atomic(char16_t) atomic_char16_t;
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typedef _Atomic(char32_t) atomic_char32_t;
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#endif
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typedef _Atomic(wchar_t) atomic_wchar_t;
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typedef _Atomic(int_least8_t) atomic_int_least8_t;
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typedef _Atomic(uint_least8_t) atomic_uint_least8_t;
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typedef _Atomic(int_least16_t) atomic_int_least16_t;
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typedef _Atomic(uint_least16_t) atomic_uint_least16_t;
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typedef _Atomic(int_least32_t) atomic_int_least32_t;
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typedef _Atomic(uint_least32_t) atomic_uint_least32_t;
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typedef _Atomic(int_least64_t) atomic_int_least64_t;
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typedef _Atomic(uint_least64_t) atomic_uint_least64_t;
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typedef _Atomic(int_fast8_t) atomic_int_fast8_t;
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typedef _Atomic(uint_fast8_t) atomic_uint_fast8_t;
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typedef _Atomic(int_fast16_t) atomic_int_fast16_t;
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typedef _Atomic(uint_fast16_t) atomic_uint_fast16_t;
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typedef _Atomic(int_fast32_t) atomic_int_fast32_t;
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typedef _Atomic(uint_fast32_t) atomic_uint_fast32_t;
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typedef _Atomic(int_fast64_t) atomic_int_fast64_t;
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typedef _Atomic(uint_fast64_t) atomic_uint_fast64_t;
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typedef _Atomic(intptr_t) atomic_intptr_t;
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typedef _Atomic(uintptr_t) atomic_uintptr_t;
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typedef _Atomic(size_t) atomic_size_t;
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typedef _Atomic(ptrdiff_t) atomic_ptrdiff_t;
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typedef _Atomic(intmax_t) atomic_intmax_t;
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typedef _Atomic(uintmax_t) atomic_uintmax_t;
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/*
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 * 7.17.7 Operations on atomic types.
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 */
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/*
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 * Compiler-specific operations.
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 */
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#if defined(__CLANG_ATOMICS)
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#define atomic_compare_exchange_strong_explicit(object, expected,          \
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                                                desired, success, failure) \
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    __c11_atomic_compare_exchange_strong(object, expected, desired,        \
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                                         success, failure)
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#define atomic_compare_exchange_weak_explicit(object, expected,          \
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                                              desired, success, failure) \
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    __c11_atomic_compare_exchange_weak(object, expected, desired,        \
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                                       success, failure)
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#define atomic_exchange_explicit(object, desired, order) \
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    __c11_atomic_exchange(object, desired, order)
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#define atomic_fetch_add_explicit(object, operand, order) \
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    __c11_atomic_fetch_add(object, operand, order)
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#define atomic_fetch_and_explicit(object, operand, order) \
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    __c11_atomic_fetch_and(object, operand, order)
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#define atomic_fetch_or_explicit(object, operand, order) \
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    __c11_atomic_fetch_or(object, operand, order)
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#define atomic_fetch_sub_explicit(object, operand, order) \
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    __c11_atomic_fetch_sub(object, operand, order)
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#define atomic_fetch_xor_explicit(object, operand, order) \
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    __c11_atomic_fetch_xor(object, operand, order)
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#define atomic_load_explicit(object, order) \
 | 
						|
    __c11_atomic_load(object, order)
 | 
						|
#define atomic_store_explicit(object, desired, order) \
 | 
						|
    __c11_atomic_store(object, desired, order)
 | 
						|
#elif defined(__GNUC_ATOMICS)
 | 
						|
#define atomic_compare_exchange_strong_explicit(object, expected,          \
 | 
						|
                                                desired, success, failure) \
 | 
						|
    __atomic_compare_exchange_n(&(object)->__val, expected,                \
 | 
						|
                                desired, 0, success, failure)
 | 
						|
#define atomic_compare_exchange_weak_explicit(object, expected,          \
 | 
						|
                                              desired, success, failure) \
 | 
						|
    __atomic_compare_exchange_n(&(object)->__val, expected,              \
 | 
						|
                                desired, 1, success, failure)
 | 
						|
#define atomic_exchange_explicit(object, desired, order) \
 | 
						|
    __atomic_exchange_n(&(object)->__val, desired, order)
 | 
						|
#define atomic_fetch_add_explicit(object, operand, order) \
 | 
						|
    __atomic_fetch_add(&(object)->__val, operand, order)
 | 
						|
#define atomic_fetch_and_explicit(object, operand, order) \
 | 
						|
    __atomic_fetch_and(&(object)->__val, operand, order)
 | 
						|
#define atomic_fetch_or_explicit(object, operand, order) \
 | 
						|
    __atomic_fetch_or(&(object)->__val, operand, order)
 | 
						|
#define atomic_fetch_sub_explicit(object, operand, order) \
 | 
						|
    __atomic_fetch_sub(&(object)->__val, operand, order)
 | 
						|
#define atomic_fetch_xor_explicit(object, operand, order) \
 | 
						|
    __atomic_fetch_xor(&(object)->__val, operand, order)
 | 
						|
#define atomic_load_explicit(object, order) \
 | 
						|
    __atomic_load_n(&(object)->__val, order)
 | 
						|
#define atomic_store_explicit(object, desired, order) \
 | 
						|
    __atomic_store_n(&(object)->__val, desired, order)
 | 
						|
#else
 | 
						|
#define __atomic_apply_stride(object, operand) \
 | 
						|
    (((__typeof__((object)->__val))0) + (operand))
 | 
						|
#define atomic_compare_exchange_strong_explicit(object, expected,                          \
 | 
						|
                                                desired, success, failure) __extension__({ \
 | 
						|
    __typeof__(expected) __ep = (expected);                                                \
 | 
						|
    __typeof__(*__ep) __e = *__ep;                                                         \
 | 
						|
    (void)(success);                                                                       \
 | 
						|
    (void)(failure);                                                                       \
 | 
						|
    (bool)((*__ep = __sync_val_compare_and_swap(&(object)->__val,                          \
 | 
						|
                                                __e, desired)) == __e);                    \
 | 
						|
})
 | 
						|
#define atomic_compare_exchange_weak_explicit(object, expected,          \
 | 
						|
                                              desired, success, failure) \
 | 
						|
    atomic_compare_exchange_strong_explicit(object, expected,            \
 | 
						|
                                            desired, success, failure)
 | 
						|
#ifdef __HAS_BUILTIN_SYNC_SWAP
 | 
						|
/* Clang provides a full-barrier atomic exchange - use it if available. */
 | 
						|
#define atomic_exchange_explicit(object, desired, order) \
 | 
						|
    ((void)(order), __sync_swap(&(object)->__val, desired))
 | 
						|
#else
 | 
						|
/*
 | 
						|
 * __sync_lock_test_and_set() is only an acquire barrier in theory (although in
 | 
						|
 * practice it is usually a full barrier) so we need an explicit barrier before
 | 
						|
 * it.
 | 
						|
 */
 | 
						|
#define atomic_exchange_explicit(object, desired, order) \
 | 
						|
    __extension__({                                      \
 | 
						|
        __typeof__(object) __o = (object);               \
 | 
						|
        __typeof__(desired) __d = (desired);             \
 | 
						|
        (void)(order);                                   \
 | 
						|
        __sync_synchronize();                            \
 | 
						|
        __sync_lock_test_and_set(&(__o)->__val, __d);    \
 | 
						|
    })
 | 
						|
#endif
 | 
						|
#define atomic_fetch_add_explicit(object, operand, order)  \
 | 
						|
    ((void)(order), __sync_fetch_and_add(&(object)->__val, \
 | 
						|
                                         __atomic_apply_stride(object, operand)))
 | 
						|
#define atomic_fetch_and_explicit(object, operand, order) \
 | 
						|
    ((void)(order), __sync_fetch_and_and(&(object)->__val, operand))
 | 
						|
#define atomic_fetch_or_explicit(object, operand, order) \
 | 
						|
    ((void)(order), __sync_fetch_and_or(&(object)->__val, operand))
 | 
						|
#define atomic_fetch_sub_explicit(object, operand, order)  \
 | 
						|
    ((void)(order), __sync_fetch_and_sub(&(object)->__val, \
 | 
						|
                                         __atomic_apply_stride(object, operand)))
 | 
						|
#define atomic_fetch_xor_explicit(object, operand, order) \
 | 
						|
    ((void)(order), __sync_fetch_and_xor(&(object)->__val, operand))
 | 
						|
#define atomic_load_explicit(object, order) \
 | 
						|
    ((void)(order), __sync_fetch_and_add(&(object)->__val, 0))
 | 
						|
#define atomic_store_explicit(object, desired, order) \
 | 
						|
    ((void)atomic_exchange_explicit(object, desired, order))
 | 
						|
#endif
 | 
						|
/*
 | 
						|
 * Convenience functions.
 | 
						|
 *
 | 
						|
 * Don't provide these in kernel space. In kernel space, we should be
 | 
						|
 * disciplined enough to always provide explicit barriers.
 | 
						|
 */
 | 
						|
#ifndef _KERNEL
 | 
						|
#define atomic_compare_exchange_strong(object, expected, desired) \
 | 
						|
    atomic_compare_exchange_strong_explicit(object, expected,     \
 | 
						|
                                            desired, memory_order_seq_cst, memory_order_seq_cst)
 | 
						|
#define atomic_compare_exchange_weak(object, expected, desired) \
 | 
						|
    atomic_compare_exchange_weak_explicit(object, expected,     \
 | 
						|
                                          desired, memory_order_seq_cst, memory_order_seq_cst)
 | 
						|
#define atomic_exchange(object, desired) \
 | 
						|
    atomic_exchange_explicit(object, desired, memory_order_seq_cst)
 | 
						|
#define atomic_fetch_add(object, operand) \
 | 
						|
    atomic_fetch_add_explicit(object, operand, memory_order_seq_cst)
 | 
						|
#define atomic_fetch_and(object, operand) \
 | 
						|
    atomic_fetch_and_explicit(object, operand, memory_order_seq_cst)
 | 
						|
#define atomic_fetch_or(object, operand) \
 | 
						|
    atomic_fetch_or_explicit(object, operand, memory_order_seq_cst)
 | 
						|
#define atomic_fetch_sub(object, operand) \
 | 
						|
    atomic_fetch_sub_explicit(object, operand, memory_order_seq_cst)
 | 
						|
#define atomic_fetch_xor(object, operand) \
 | 
						|
    atomic_fetch_xor_explicit(object, operand, memory_order_seq_cst)
 | 
						|
#define atomic_load(object) \
 | 
						|
    atomic_load_explicit(object, memory_order_seq_cst)
 | 
						|
#define atomic_store(object, desired) \
 | 
						|
    atomic_store_explicit(object, desired, memory_order_seq_cst)
 | 
						|
#endif /* !_KERNEL */
 | 
						|
/*
 | 
						|
 * 7.17.8 Atomic flag type and operations.
 | 
						|
 *
 | 
						|
 * XXX: Assume atomic_bool can be used as an atomic_flag. Is there some
 | 
						|
 * kind of compiler built-in type we could use?
 | 
						|
 */
 | 
						|
typedef struct
 | 
						|
{
 | 
						|
    atomic_bool __flag;
 | 
						|
} atomic_flag;
 | 
						|
#define ATOMIC_FLAG_INIT       \
 | 
						|
    {                          \
 | 
						|
        ATOMIC_VAR_INIT(false) \
 | 
						|
    }
 | 
						|
static __inline bool
 | 
						|
atomic_flag_test_and_set_explicit(volatile atomic_flag *__object,
 | 
						|
                                  memory_order __order)
 | 
						|
{
 | 
						|
    return (atomic_exchange_explicit(&__object->__flag, 1, __order));
 | 
						|
}
 | 
						|
static __inline void
 | 
						|
atomic_flag_clear_explicit(volatile atomic_flag *__object, memory_order __order)
 | 
						|
{
 | 
						|
    atomic_store_explicit(&__object->__flag, 0, __order);
 | 
						|
}
 | 
						|
#ifndef _KERNEL
 | 
						|
static __inline bool
 | 
						|
atomic_flag_test_and_set(volatile atomic_flag *__object)
 | 
						|
{
 | 
						|
    return (atomic_flag_test_and_set_explicit(__object,
 | 
						|
                                              memory_order_seq_cst));
 | 
						|
}
 | 
						|
static __inline void
 | 
						|
atomic_flag_clear(volatile atomic_flag *__object)
 | 
						|
{
 | 
						|
    atomic_flag_clear_explicit(__object, memory_order_seq_cst);
 | 
						|
}
 | 
						|
#endif /* !_KERNEL */
 | 
						|
#endif /* <atomic> unavailable */
 | 
						|
#endif /* !_STDATOMIC_H_ */
 |