src/hb-atomic.hh - third_party/harfbuzz - Git at Google

 /*
  * Copyright © 2007  Chris Wilson
  * Copyright © 2009,2010  Red Hat, Inc.
  * Copyright © 2011,2012  Google, Inc.
  *
  *  This is part of HarfBuzz, a text shaping library.
  *
  * Permission is hereby granted, without written agreement and without
  * license or royalty fees, to use, copy, modify, and distribute this
  * software and its documentation for any purpose, provided that the
  * above copyright notice and the following two paragraphs appear in
  * all copies of this software.
  *
  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  * DAMAGE.
  *
  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  *
  * Contributor(s):
  *	Chris Wilson <chris@chris-wilson.co.uk>
  * Red Hat Author(s): Behdad Esfahbod
  * Google Author(s): Behdad Esfahbod
  */

 #ifndef HB_ATOMIC_HH
 #define HB_ATOMIC_HH

 #include "hb.hh"


 /*
  * Atomic integers and pointers.
  */


 /* We need external help for these */

 #if defined(hb_atomic_int_impl_add) \
  && defined(hb_atomic_ptr_impl_get) \
  && defined(hb_atomic_ptr_impl_cmpexch)

 /* Defined externally, i.e. in config.h. */


 #elif !defined(HB_NO_MT) && defined(__ATOMIC_ACQUIRE)

 /* C++11-style GCC primitives. */

 #define _hb_memory_barrier()			__sync_synchronize ()

 #define hb_atomic_int_impl_add(AI, V)		__atomic_fetch_add ((AI), (V), __ATOMIC_ACQ_REL)
 #define hb_atomic_int_impl_set_relaxed(AI, V)	__atomic_store_n ((AI), (V), __ATOMIC_RELAXED)
 #define hb_atomic_int_impl_set(AI, V)		__atomic_store_n ((AI), (V), __ATOMIC_RELEASE)
 #define hb_atomic_int_impl_get_relaxed(AI)	__atomic_load_n ((AI), __ATOMIC_RELAXED)
 #define hb_atomic_int_impl_get(AI)		__atomic_load_n ((AI), __ATOMIC_ACQUIRE)

 #define hb_atomic_ptr_impl_set_relaxed(P, V)	__atomic_store_n ((P), (V), __ATOMIC_RELAXED)
 #define hb_atomic_ptr_impl_get_relaxed(P)	__atomic_load_n ((P), __ATOMIC_RELAXED)
 #define hb_atomic_ptr_impl_get(P)		__atomic_load_n ((P), __ATOMIC_ACQUIRE)
 static inline bool
 _hb_atomic_ptr_impl_cmplexch (const void **P, const void *O_, const void *N)
 {
   const void *O = O_; // Need lvalue
   return __atomic_compare_exchange_n ((void **) P, (void **) &O, (void *) N, true, __ATOMIC_ACQ_REL, __ATOMIC_RELAXED);
 }
 #define hb_atomic_ptr_impl_cmpexch(P,O,N)	_hb_atomic_ptr_impl_cmplexch ((const void **) (P), (O), (N))

 #elif !defined(HB_NO_MT) && __cplusplus >= 201103L

 /* C++11 atomics. */

 #include <atomic>

 #define _hb_memory_barrier()			std::atomic_thread_fence(std::memory_order_ack_rel)
 #define _hb_memory_r_barrier()			std::atomic_thread_fence(std::memory_order_acquire)
 #define _hb_memory_w_barrier()			std::atomic_thread_fence(std::memory_order_release)

 #define hb_atomic_int_impl_add(AI, V)		(reinterpret_cast<std::atomic<int> *> (AI)->fetch_add ((V), std::memory_order_acq_rel))
 #define hb_atomic_int_impl_set_relaxed(AI, V)	(reinterpret_cast<std::atomic<int> *> (AI)->store ((V), std::memory_order_relaxed))
 #define hb_atomic_int_impl_set(AI, V)		(reinterpret_cast<std::atomic<int> *> (AI)->store ((V), std::memory_order_release))
 #define hb_atomic_int_impl_get_relaxed(AI)	(reinterpret_cast<std::atomic<int> *> (AI)->load (std::memory_order_relaxed))
 #define hb_atomic_int_impl_get(AI)		(reinterpret_cast<std::atomic<int> *> (AI)->load (std::memory_order_acquire))

 #define hb_atomic_ptr_impl_set_relaxed(P, V)	(reinterpret_cast<std::atomic<void*> *> (P)->store ((V), std::memory_order_relaxed))
 #define hb_atomic_ptr_impl_get_relaxed(P)	(reinterpret_cast<std::atomic<void*> *> (P)->load (std::memory_order_relaxed))
 #define hb_atomic_ptr_impl_get(P)		(reinterpret_cast<std::atomic<void*> *> (P)->load (std::memory_order_acquire))
 static inline bool
 _hb_atomic_ptr_impl_cmplexch (const void **P, const void *O_, const void *N)
 {
   const void *O = O_; // Need lvalue
   return reinterpret_cast<std::atomic<const void*> *> (P)->compare_exchange_weak (O, N, std::memory_order_acq_rel, std::memory_order_relaxed);
 }
 #define hb_atomic_ptr_impl_cmpexch(P,O,N)	_hb_atomic_ptr_impl_cmplexch ((const void **) (P), (O), (N))


 #elif !defined(HB_NO_MT) && (defined(_WIN32) || defined(__CYGWIN__))

 #include <windows.h>

 static inline void _hb_memory_barrier (void)
 {
 #if !defined(MemoryBarrier)
   /* MinGW has a convoluted history of supporting MemoryBarrier. */
   LONG dummy = 0;
   InterlockedExchange (&dummy, 1);
 #else
   MemoryBarrier ();
 #endif
 }
 #define _hb_memory_barrier()			_hb_memory_barrier ()

 #define hb_atomic_int_impl_add(AI, V)		InterlockedExchangeAdd ((LONG *) (AI), (V))
 static_assert ((sizeof (LONG) == sizeof (int)), "");

 #define hb_atomic_ptr_impl_cmpexch(P,O,N)	(InterlockedCompareExchangePointer ((P), (N), (O)) == (O))


 #elif !defined(HB_NO_MT) && defined(HAVE_INTEL_ATOMIC_PRIMITIVES)

 #define _hb_memory_barrier()			__sync_synchronize ()

 #define hb_atomic_int_impl_add(AI, V)		__sync_fetch_and_add ((AI), (V))

 #define hb_atomic_ptr_impl_cmpexch(P,O,N)	__sync_bool_compare_and_swap ((P), (O), (N))


 #elif !defined(HB_NO_MT) && defined(HAVE_SOLARIS_ATOMIC_OPS)

 #include <atomic.h>
 #include <mbarrier.h>

 #define _hb_memory_r_barrier()			__machine_r_barrier ()
 #define _hb_memory_w_barrier()			__machine_w_barrier ()
 #define _hb_memory_barrier()			__machine_rw_barrier ()

 static inline int _hb_fetch_and_add (int *AI, int V)
 {
   _hb_memory_w_barrier ();
   int result = atomic_add_int_nv ((uint_t *) AI, V);
   _hb_memory_r_barrier ();
   return result;
 }
 static inline bool _hb_compare_and_swap_ptr (void **P, void *O, void *N)
 {
   _hb_memory_w_barrier ();
   bool result = atomic_cas_ptr (P, O, N) == O;
   _hb_memory_r_barrier ();
   return result;
 }

 #define hb_atomic_int_impl_add(AI, V)           _hb_fetch_and_add ((AI), (V))

 #define hb_atomic_ptr_impl_cmpexch(P,O,N)       _hb_compare_and_swap_ptr ((P), (O), (N))


 #elif !defined(HB_NO_MT) && defined(__APPLE__)

 #include <libkern/OSAtomic.h>
 #ifdef __MAC_OS_X_MIN_REQUIRED
 #include <AvailabilityMacros.h>
 #elif defined(__IPHONE_OS_MIN_REQUIRED)
 #include <Availability.h>
 #endif

 #define _hb_memory_barrier()			OSMemoryBarrier ()

 #define hb_atomic_int_impl_add(AI, V)		(OSAtomicAdd32Barrier ((V), (AI)) - (V))

 #if (MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_4 || __IPHONE_VERSION_MIN_REQUIRED >= 20100)
 #define hb_atomic_ptr_impl_cmpexch(P,O,N)	OSAtomicCompareAndSwapPtrBarrier ((O), (N), (P))
 #else
 #if __ppc64__ || __x86_64__ || __aarch64__
 #define hb_atomic_ptr_impl_cmpexch(P,O,N)	OSAtomicCompareAndSwap64Barrier ((int64_t) (O), (int64_t) (N), (int64_t*) (P))
 #else
 #define hb_atomic_ptr_impl_cmpexch(P,O,N)	OSAtomicCompareAndSwap32Barrier ((int32_t) (O), (int32_t) (N), (int32_t*) (P))
 #endif
 #endif


 #elif !defined(HB_NO_MT) && defined(_AIX) && defined(__IBMCPP__)

 #include <builtins.h>

 #define _hb_memory_barrier()			__lwsync ()

 static inline int _hb_fetch_and_add (int *AI, int V)
 {
   _hb_memory_barrier ();
   int result = __fetch_and_add (AI, V);
   _hb_memory_barrier ();
   return result;
 }
 static inline bool _hb_compare_and_swaplp (long *P, long O, long N)
 {
   _hb_memory_barrier ();
   bool result = __compare_and_swaplp (P, &O, N);
   _hb_memory_barrier ();
   return result;
 }

 #define hb_atomic_int_impl_add(AI, V)           _hb_fetch_and_add ((AI), (V))

 #define hb_atomic_ptr_impl_cmpexch(P,O,N)       _hb_compare_and_swaplp ((long *) (P), (long) (O), (long) (N))
 static_assert ((sizeof (long) == sizeof (void *)), "");


 #elif !defined(HB_NO_MT)

 #define HB_ATOMIC_INT_NIL 1 /* Warn that fallback implementation is in use. */

 #define _hb_memory_barrier()

 #define hb_atomic_int_impl_add(AI, V)		((*(AI) += (V)) - (V))

 #define hb_atomic_ptr_impl_cmpexch(P,O,N)	(* (void **) (P) == (void *) (O) ? (* (void **) (P) = (void *) (N), true) : false)


 #else /* HB_NO_MT */

 #define hb_atomic_int_impl_add(AI, V)		((*(AI) += (V)) - (V))

 #define _hb_memory_barrier()

 #define hb_atomic_ptr_impl_cmpexch(P,O,N)	(* (void **) (P) == (void *) (O) ? (* (void **) (P) = (void *) (N), true) : false)


 #endif


 #ifndef _hb_memory_r_barrier
 #define _hb_memory_r_barrier()			_hb_memory_barrier ()
 #endif
 #ifndef _hb_memory_w_barrier
 #define _hb_memory_w_barrier()			_hb_memory_barrier ()
 #endif
 #ifndef hb_atomic_int_impl_set_relaxed
 #define hb_atomic_int_impl_set_relaxed(AI, V)	(*(AI) = (V))
 #endif
 #ifndef hb_atomic_int_impl_get_relaxed
 #define hb_atomic_int_impl_get_relaxed(AI)	(*(AI))
 #endif

 #ifndef hb_atomic_ptr_impl_set_relaxed
 #define hb_atomic_ptr_impl_set_relaxed(P, V)	(*(P) = (V))
 #endif
 #ifndef hb_atomic_ptr_impl_get_relaxed
 #define hb_atomic_ptr_impl_get_relaxed(P)	(*(P))
 #endif
 #ifndef hb_atomic_int_impl_set
 inline void hb_atomic_int_impl_set (int *AI, int v)	{ _hb_memory_w_barrier (); *AI = v; }
 #endif
 #ifndef hb_atomic_int_impl_get
 inline int hb_atomic_int_impl_get (int *AI)	{ int v = *AI; _hb_memory_r_barrier (); return v; }
 #endif
 #ifndef hb_atomic_ptr_impl_get
 inline void *hb_atomic_ptr_impl_get (void **P)	{ void *v = *P; _hb_memory_r_barrier (); return v; }
 #endif


 #define HB_ATOMIC_INT_INIT(V)          {V}
 struct hb_atomic_int_t
 {
   inline void set_relaxed (int v_) const { hb_atomic_int_impl_set_relaxed (&v, v_); }
   inline void set (int v_) const { hb_atomic_int_impl_set (&v, v_); }
   inline int get_relaxed (void) const { return hb_atomic_int_impl_get_relaxed (&v); }
   inline int get (void) const { return hb_atomic_int_impl_get (&v); }
   inline int inc (void) { return hb_atomic_int_impl_add (&v,  1); }
   inline int dec (void) { return hb_atomic_int_impl_add (&v, -1); }

   mutable int v;
 };


 #define HB_ATOMIC_PTR_INIT(V)          {V}
 template <typename P>
 struct hb_atomic_ptr_t
 {
   typedef typename hb_remove_pointer<P>::value T;

   inline void init (T* v_ = nullptr) { set_relaxed (v_); }
   inline void set_relaxed (T* v_) const { hb_atomic_ptr_impl_set_relaxed (&v, v_); }
   inline T *get_relaxed (void) const { return (T *) hb_atomic_ptr_impl_get_relaxed (&v); }
   inline T *get (void) const { return (T *) hb_atomic_ptr_impl_get ((void **) &v); }
   inline bool cmpexch (const T *old, T *new_) const { return hb_atomic_ptr_impl_cmpexch ((void **) &v, (void *) old, (void *) new_); }

   inline T * operator -> (void) const { return get (); }
   template <typename C> inline operator C * (void) const { return get (); }

   mutable T *v;
 };


 #endif /* HB_ATOMIC_HH */
	/*
	* Copyright © 2007 Chris Wilson
	* Copyright © 2009,2010 Red Hat, Inc.
	* Copyright © 2011,2012 Google, Inc.
	*
	* This is part of HarfBuzz, a text shaping library.
	*
	* Permission is hereby granted, without written agreement and without
	* license or royalty fees, to use, copy, modify, and distribute this
	* software and its documentation for any purpose, provided that the
	* above copyright notice and the following two paragraphs appear in
	* all copies of this software.
	*
	* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
	* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
	* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
	* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
	* DAMAGE.
	*
	* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
	* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
	* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
	* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
	* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
	*
	* Contributor(s):
	* Chris Wilson <chris@chris-wilson.co.uk>
	* Red Hat Author(s): Behdad Esfahbod
	* Google Author(s): Behdad Esfahbod
	*/

	#ifndef HB_ATOMIC_HH
	#define HB_ATOMIC_HH

	#include "hb.hh"


	/*
	* Atomic integers and pointers.
	*/


	/* We need external help for these */

	#if defined(hb_atomic_int_impl_add) \
	&& defined(hb_atomic_ptr_impl_get) \
	&& defined(hb_atomic_ptr_impl_cmpexch)

	/* Defined externally, i.e. in config.h. */


	#elif !defined(HB_NO_MT) && defined(__ATOMIC_ACQUIRE)

	/* C++11-style GCC primitives. */

	#define _hb_memory_barrier() __sync_synchronize ()

	#define hb_atomic_int_impl_add(AI, V) __atomic_fetch_add ((AI), (V), __ATOMIC_ACQ_REL)
	#define hb_atomic_int_impl_set_relaxed(AI, V) __atomic_store_n ((AI), (V), __ATOMIC_RELAXED)
	#define hb_atomic_int_impl_set(AI, V) __atomic_store_n ((AI), (V), __ATOMIC_RELEASE)
	#define hb_atomic_int_impl_get_relaxed(AI) __atomic_load_n ((AI), __ATOMIC_RELAXED)
	#define hb_atomic_int_impl_get(AI) __atomic_load_n ((AI), __ATOMIC_ACQUIRE)

	#define hb_atomic_ptr_impl_set_relaxed(P, V) __atomic_store_n ((P), (V), __ATOMIC_RELAXED)
	#define hb_atomic_ptr_impl_get_relaxed(P) __atomic_load_n ((P), __ATOMIC_RELAXED)
	#define hb_atomic_ptr_impl_get(P) __atomic_load_n ((P), __ATOMIC_ACQUIRE)
	static inline bool
	_hb_atomic_ptr_impl_cmplexch (const void *P, const void O_, const void *N)
	{
	const void *O = O_; // Need lvalue
	return __atomic_compare_exchange_n ((void ) P, (void ) &O, (void *) N, true, __ATOMIC_ACQ_REL, __ATOMIC_RELAXED);
	}
	#define hb_atomic_ptr_impl_cmpexch(P,O,N) _hb_atomic_ptr_impl_cmplexch ((const void **) (P), (O), (N))

	#elif !defined(HB_NO_MT) && __cplusplus >= 201103L

	/* C++11 atomics. */

	#include <atomic>

	#define _hb_memory_barrier() std::atomic_thread_fence(std::memory_order_ack_rel)
	#define _hb_memory_r_barrier() std::atomic_thread_fence(std::memory_order_acquire)
	#define _hb_memory_w_barrier() std::atomic_thread_fence(std::memory_order_release)

	#define hb_atomic_int_impl_add(AI, V) (reinterpret_cast<std::atomic<int> *> (AI)->fetch_add ((V), std::memory_order_acq_rel))
	#define hb_atomic_int_impl_set_relaxed(AI, V) (reinterpret_cast<std::atomic<int> *> (AI)->store ((V), std::memory_order_relaxed))
	#define hb_atomic_int_impl_set(AI, V) (reinterpret_cast<std::atomic<int> *> (AI)->store ((V), std::memory_order_release))
	#define hb_atomic_int_impl_get_relaxed(AI) (reinterpret_cast<std::atomic<int> *> (AI)->load (std::memory_order_relaxed))
	#define hb_atomic_int_impl_get(AI) (reinterpret_cast<std::atomic<int> *> (AI)->load (std::memory_order_acquire))

	#define hb_atomic_ptr_impl_set_relaxed(P, V) (reinterpret_cast<std::atomic<void> > (P)->store ((V), std::memory_order_relaxed))
	#define hb_atomic_ptr_impl_get_relaxed(P) (reinterpret_cast<std::atomic<void> > (P)->load (std::memory_order_relaxed))
	#define hb_atomic_ptr_impl_get(P) (reinterpret_cast<std::atomic<void> > (P)->load (std::memory_order_acquire))
	static inline bool
	_hb_atomic_ptr_impl_cmplexch (const void *P, const void O_, const void *N)
	{
	const void *O = O_; // Need lvalue
	return reinterpret_cast<std::atomic<const void> > (P)->compare_exchange_weak (O, N, std::memory_order_acq_rel, std::memory_order_relaxed);
	}
	#define hb_atomic_ptr_impl_cmpexch(P,O,N) _hb_atomic_ptr_impl_cmplexch ((const void **) (P), (O), (N))


	#elif !defined(HB_NO_MT) && (defined(_WIN32) \|\| defined(__CYGWIN__))

	#include <windows.h>

	static inline void _hb_memory_barrier (void)
	{
	#if !defined(MemoryBarrier)
	/* MinGW has a convoluted history of supporting MemoryBarrier. */
	LONG dummy = 0;
	InterlockedExchange (&dummy, 1);
	#else
	MemoryBarrier ();
	#endif
	}
	#define _hb_memory_barrier() _hb_memory_barrier ()

	#define hb_atomic_int_impl_add(AI, V) InterlockedExchangeAdd ((LONG *) (AI), (V))
	static_assert ((sizeof (LONG) == sizeof (int)), "");

	#define hb_atomic_ptr_impl_cmpexch(P,O,N) (InterlockedCompareExchangePointer ((P), (N), (O)) == (O))


	#elif !defined(HB_NO_MT) && defined(HAVE_INTEL_ATOMIC_PRIMITIVES)

	#define _hb_memory_barrier() __sync_synchronize ()

	#define hb_atomic_int_impl_add(AI, V) __sync_fetch_and_add ((AI), (V))

	#define hb_atomic_ptr_impl_cmpexch(P,O,N) __sync_bool_compare_and_swap ((P), (O), (N))


	#elif !defined(HB_NO_MT) && defined(HAVE_SOLARIS_ATOMIC_OPS)

	#include <atomic.h>
	#include <mbarrier.h>

	#define _hb_memory_r_barrier() __machine_r_barrier ()
	#define _hb_memory_w_barrier() __machine_w_barrier ()
	#define _hb_memory_barrier() __machine_rw_barrier ()

	static inline int _hb_fetch_and_add (int *AI, int V)
	{
	_hb_memory_w_barrier ();
	int result = atomic_add_int_nv ((uint_t *) AI, V);
	_hb_memory_r_barrier ();
	return result;
	}
	static inline bool _hb_compare_and_swap_ptr (void *P, void O, void *N)
	{
	_hb_memory_w_barrier ();
	bool result = atomic_cas_ptr (P, O, N) == O;
	_hb_memory_r_barrier ();
	return result;
	}

	#define hb_atomic_int_impl_add(AI, V) _hb_fetch_and_add ((AI), (V))

	#define hb_atomic_ptr_impl_cmpexch(P,O,N) _hb_compare_and_swap_ptr ((P), (O), (N))


	#elif !defined(HB_NO_MT) && defined(__APPLE__)

	#include <libkern/OSAtomic.h>
	#ifdef __MAC_OS_X_MIN_REQUIRED
	#include <AvailabilityMacros.h>
	#elif defined(__IPHONE_OS_MIN_REQUIRED)
	#include <Availability.h>
	#endif

	#define _hb_memory_barrier() OSMemoryBarrier ()

	#define hb_atomic_int_impl_add(AI, V) (OSAtomicAdd32Barrier ((V), (AI)) - (V))

	#if (MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_4 \|\| __IPHONE_VERSION_MIN_REQUIRED >= 20100)
	#define hb_atomic_ptr_impl_cmpexch(P,O,N) OSAtomicCompareAndSwapPtrBarrier ((O), (N), (P))
	#else
	#if __ppc64__ \|\| __x86_64__ \|\| __aarch64__
	#define hb_atomic_ptr_impl_cmpexch(P,O,N) OSAtomicCompareAndSwap64Barrier ((int64_t) (O), (int64_t) (N), (int64_t*) (P))
	#else
	#define hb_atomic_ptr_impl_cmpexch(P,O,N) OSAtomicCompareAndSwap32Barrier ((int32_t) (O), (int32_t) (N), (int32_t*) (P))
	#endif
	#endif


	#elif !defined(HB_NO_MT) && defined(_AIX) && defined(__IBMCPP__)

	#include <builtins.h>

	#define _hb_memory_barrier() __lwsync ()

	static inline int _hb_fetch_and_add (int *AI, int V)
	{
	_hb_memory_barrier ();
	int result = __fetch_and_add (AI, V);
	_hb_memory_barrier ();
	return result;
	}
	static inline bool _hb_compare_and_swaplp (long *P, long O, long N)
	{
	_hb_memory_barrier ();
	bool result = __compare_and_swaplp (P, &O, N);
	_hb_memory_barrier ();
	return result;
	}

	#define hb_atomic_int_impl_add(AI, V) _hb_fetch_and_add ((AI), (V))

	#define hb_atomic_ptr_impl_cmpexch(P,O,N) _hb_compare_and_swaplp ((long *) (P), (long) (O), (long) (N))
	static_assert ((sizeof (long) == sizeof (void *)), "");


	#elif !defined(HB_NO_MT)

	#define HB_ATOMIC_INT_NIL 1 /* Warn that fallback implementation is in use. */

	#define _hb_memory_barrier()

	#define hb_atomic_int_impl_add(AI, V) ((*(AI) += (V)) - (V))

	#define hb_atomic_ptr_impl_cmpexch(P,O,N) (* (void *) (P) == (void ) (O) ? (* (void *) (P) = (void ) (N), true) : false)


	#else /* HB_NO_MT */

	#define hb_atomic_int_impl_add(AI, V) ((*(AI) += (V)) - (V))

	#define _hb_memory_barrier()

	#define hb_atomic_ptr_impl_cmpexch(P,O,N) (* (void *) (P) == (void ) (O) ? (* (void *) (P) = (void ) (N), true) : false)


	#endif


	#ifndef _hb_memory_r_barrier
	#define _hb_memory_r_barrier() _hb_memory_barrier ()
	#endif
	#ifndef _hb_memory_w_barrier
	#define _hb_memory_w_barrier() _hb_memory_barrier ()
	#endif
	#ifndef hb_atomic_int_impl_set_relaxed
	#define hb_atomic_int_impl_set_relaxed(AI, V) (*(AI) = (V))
	#endif
	#ifndef hb_atomic_int_impl_get_relaxed
	#define hb_atomic_int_impl_get_relaxed(AI) (*(AI))
	#endif

	#ifndef hb_atomic_ptr_impl_set_relaxed
	#define hb_atomic_ptr_impl_set_relaxed(P, V) (*(P) = (V))
	#endif
	#ifndef hb_atomic_ptr_impl_get_relaxed
	#define hb_atomic_ptr_impl_get_relaxed(P) (*(P))
	#endif
	#ifndef hb_atomic_int_impl_set
	inline void hb_atomic_int_impl_set (int AI, int v) { _hb_memory_w_barrier (); AI = v; }
	#endif
	#ifndef hb_atomic_int_impl_get
	inline int hb_atomic_int_impl_get (int AI) { int v = AI; _hb_memory_r_barrier (); return v; }
	#endif
	#ifndef hb_atomic_ptr_impl_get
	inline void hb_atomic_ptr_impl_get (void P) { void v = *P; _hb_memory_r_barrier (); return v; }
	#endif


	#define HB_ATOMIC_INT_INIT(V) {V}
	struct hb_atomic_int_t
	{
	inline void set_relaxed (int v_) const { hb_atomic_int_impl_set_relaxed (&v, v_); }
	inline void set (int v_) const { hb_atomic_int_impl_set (&v, v_); }
	inline int get_relaxed (void) const { return hb_atomic_int_impl_get_relaxed (&v); }
	inline int get (void) const { return hb_atomic_int_impl_get (&v); }
	inline int inc (void) { return hb_atomic_int_impl_add (&v, 1); }
	inline int dec (void) { return hb_atomic_int_impl_add (&v, -1); }

	mutable int v;
	};


	#define HB_ATOMIC_PTR_INIT(V) {V}
	template <typename P>
	struct hb_atomic_ptr_t
	{
	typedef typename hb_remove_pointer<P>::value T;

	inline void init (T* v_ = nullptr) { set_relaxed (v_); }
	inline void set_relaxed (T* v_) const { hb_atomic_ptr_impl_set_relaxed (&v, v_); }
	inline T get_relaxed (void) const { return (T ) hb_atomic_ptr_impl_get_relaxed (&v); }
	inline T get (void) const { return (T ) hb_atomic_ptr_impl_get ((void **) &v); }
	inline bool cmpexch (const T old, T new_) const { return hb_atomic_ptr_impl_cmpexch ((void *) &v, (void ) old, (void *) new_); }

	inline T * operator -> (void) const { return get (); }
	template <typename C> inline operator C * (void) const { return get (); }

	mutable T *v;
	};


	#endif /* HB_ATOMIC_HH */