harfbuzz/src/hb-atomic.hh
Behdad Esfahbod 227d85e138 Minor
2019-05-10 23:16:14 -07:00

302 lines
10 KiB
C++

/*
* 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"
#include "hb-meta.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> const *> (AI)->load (std::memory_order_relaxed))
#define hb_atomic_int_impl_get(AI) (reinterpret_cast<std::atomic<int> const *> (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*> const *> (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)
#include <windows.h>
static inline void _hb_memory_barrier ()
{
#ifndef 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) - 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__) || defined(__ibmxl__))
#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 (const 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 ** const P) { void *v = *P; _hb_memory_r_barrier (); return v; }
#endif
#define HB_ATOMIC_INT_INIT(V) {V}
struct hb_atomic_int_t
{
void set_relaxed (int v_) { hb_atomic_int_impl_set_relaxed (&v, v_); }
void set (int v_) { hb_atomic_int_impl_set (&v, v_); }
int get_relaxed () const { return hb_atomic_int_impl_get_relaxed (&v); }
int get () const { return hb_atomic_int_impl_get (&v); }
int inc () { return hb_atomic_int_impl_add (&v, 1); }
int dec () { return hb_atomic_int_impl_add (&v, -1); }
int v;
};
#define HB_ATOMIC_PTR_INIT(V) {V}
template <typename P>
struct hb_atomic_ptr_t
{
typedef hb_remove_pointer<P> T;
void init (T* v_ = nullptr) { set_relaxed (v_); }
void set_relaxed (T* v_) { hb_atomic_ptr_impl_set_relaxed (&v, v_); }
T *get_relaxed () const { return (T *) hb_atomic_ptr_impl_get_relaxed (&v); }
T *get () const { return (T *) hb_atomic_ptr_impl_get ((void **) &v); }
bool cmpexch (const T *old, T *new_) const { return hb_atomic_ptr_impl_cmpexch ((void **) &v, (void *) old, (void *) new_); }
T * operator -> () const { return get (); }
template <typename C> operator C * () const { return get (); }
T *v;
};
#endif /* HB_ATOMIC_HH */