[apple/objc4.git] / runtime / objc-auto.h

/*
 * Copyright (c) 2004-2007 Apple Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

#ifndef _OBJC_AUTO_H_
#define _OBJC_AUTO_H_

#include <objc/objc.h>
#include <malloc/malloc.h>
#include <stdint.h>
#include <stddef.h>
#include <string.h>
#include <Availability.h>
#include <AvailabilityMacros.h>
#include <TargetConditionals.h>

#if !TARGET_OS_WIN32
#include <sys/types.h>
#include <libkern/OSAtomic.h>
#else
#   define WINVER 0x0501		// target Windows XP and later
#   define _WIN32_WINNT 0x0501	// target Windows XP and later
#   define WIN32_LEAN_AND_MEAN
// workaround: windef.h typedefs BOOL as int
#   define BOOL WINBOOL
#   include <windows.h>
#   undef BOOL
#endif


/* GC is unsupported on some architectures. */

#if TARGET_OS_EMBEDDED  ||  TARGET_OS_IPHONE  ||  TARGET_OS_WIN32
#   define OBJC_NO_GC 1
#endif


/* objc_collect() options */
enum {
    // choose one
    OBJC_RATIO_COLLECTION        = (0 << 0),  // run "ratio" generational collections, then a full
    OBJC_GENERATIONAL_COLLECTION = (1 << 0),  // run fast incremental collection
    OBJC_FULL_COLLECTION         = (2 << 0),  // run full collection.
    OBJC_EXHAUSTIVE_COLLECTION   = (3 << 0),  // run full collections until memory available stops improving
    
    OBJC_COLLECT_IF_NEEDED       = (1 << 3), // run collection only if needed (allocation threshold exceeded)
    OBJC_WAIT_UNTIL_DONE         = (1 << 4), // wait (when possible) for collection to end before returning (when collector is running on dedicated thread)
};

/* objc_clear_stack() options */
enum {
    OBJC_CLEAR_RESIDENT_STACK = (1 << 0)
};

#ifndef OBJC_NO_GC


/* GC declarations */

/* Collection utilities */

OBJC_EXPORT void objc_collect(unsigned long options)
    __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA);
OBJC_EXPORT BOOL objc_collectingEnabled(void)
    __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);
OBJC_EXPORT malloc_zone_t *objc_collectableZone(void) 
    __OSX_AVAILABLE_STARTING(__MAC_10_7, __IPHONE_NA);

/* GC configuration */

/* Tells collector to wait until specified bytes have been allocated before trying to collect again. */
OBJC_EXPORT void objc_setCollectionThreshold(size_t threshold)
    __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);

/* Tells collector to run a full collection for every ratio generational collections. */
OBJC_EXPORT void objc_setCollectionRatio(size_t ratio)
    __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);

// 
// GC-safe compare-and-swap
//

/* Atomic update, with write barrier. */
OBJC_EXPORT BOOL objc_atomicCompareAndSwapPtr(id predicate, id replacement, volatile id *objectLocation) 
    __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;
/* "Barrier" version also includes memory barrier. */
OBJC_EXPORT BOOL objc_atomicCompareAndSwapPtrBarrier(id predicate, id replacement, volatile id *objectLocation) 
    __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;

// atomic update of a global variable
OBJC_EXPORT BOOL objc_atomicCompareAndSwapGlobal(id predicate, id replacement, volatile id *objectLocation)
    __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;
OBJC_EXPORT BOOL objc_atomicCompareAndSwapGlobalBarrier(id predicate, id replacement, volatile id *objectLocation)
    __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;
// atomic update of an instance variable
OBJC_EXPORT BOOL objc_atomicCompareAndSwapInstanceVariable(id predicate, id replacement, volatile id *objectLocation)
    __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;
OBJC_EXPORT BOOL objc_atomicCompareAndSwapInstanceVariableBarrier(id predicate, id replacement, volatile id *objectLocation)
    __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;


// 
// Read and write barriers
// 

OBJC_EXPORT id objc_assign_strongCast(id val, id *dest)
    __OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_NA);
OBJC_EXPORT id objc_assign_global(id val, id *dest)
    __OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_NA);
OBJC_EXPORT id objc_assign_threadlocal(id val, id *dest)
    __OSX_AVAILABLE_STARTING(__MAC_10_7, __IPHONE_NA);
OBJC_EXPORT id objc_assign_ivar(id value, id dest, ptrdiff_t offset)
    __OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_NA);
OBJC_EXPORT void *objc_memmove_collectable(void *dst, const void *src, size_t size)
    __OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_NA);

OBJC_EXPORT id objc_read_weak(id *location)
    __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);
OBJC_EXPORT id objc_assign_weak(id value, id *location)
    __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);


//
// Thread management
// 

/* Register the calling thread with the garbage collector. */
OBJC_EXPORT void objc_registerThreadWithCollector(void)
    __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA);

/* Unregisters the calling thread with the garbage collector. 
   Unregistration also happens automatically at thread exit. */
OBJC_EXPORT void objc_unregisterThreadWithCollector(void)
    __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA);

/* To be called from code which must only execute on a registered thread. */
/* If the calling thread is unregistered then an error message is emitted and the thread is implicitly registered. */
OBJC_EXPORT void objc_assertRegisteredThreadWithCollector(void)
    __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA);

/* Erases any stale references in unused parts of the stack. */
OBJC_EXPORT void objc_clear_stack(unsigned long options)
    __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);


//
// Finalization
// 

/* Returns true if object has been scheduled for finalization.  Can be used to avoid operations that may lead to resurrection, which are fatal. */
OBJC_EXPORT BOOL objc_is_finalized(void *ptr)
    __OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_NA);

// Deprcated. Tells runtime to issue finalize calls on the main thread only.
OBJC_EXPORT void objc_finalizeOnMainThread(Class cls)
    AVAILABLE_MAC_OS_X_VERSION_10_5_AND_LATER_BUT_DEPRECATED;


//
// Deprecated names. 
//

/* Deprecated. Use objc_collectingEnabled() instead. */
OBJC_EXPORT BOOL objc_collecting_enabled(void)
    __OSX_AVAILABLE_BUT_DEPRECATED(__MAC_10_4,__MAC_10_5, __IPHONE_NA,__IPHONE_NA);
/* Deprecated. Use objc_setCollectionThreshold() instead. */
OBJC_EXPORT void objc_set_collection_threshold(size_t threshold)
    __OSX_AVAILABLE_BUT_DEPRECATED(__MAC_10_4,__MAC_10_5, __IPHONE_NA,__IPHONE_NA);
/* Deprecated. Use objc_setCollectionRatio() instead. */
OBJC_EXPORT void objc_set_collection_ratio(size_t ratio)
    __OSX_AVAILABLE_BUT_DEPRECATED(__MAC_10_4,__MAC_10_5, __IPHONE_NA,__IPHONE_NA);
/* Deprecated. Use objc_startCollectorThread() instead. */
OBJC_EXPORT void objc_start_collector_thread(void)
    __OSX_AVAILABLE_BUT_DEPRECATED(__MAC_10_4,__MAC_10_5, __IPHONE_NA,__IPHONE_NA);
/* Deprecated. No replacement. Formerly told the collector to run using a dedicated background thread. */
OBJC_EXPORT void objc_startCollectorThread(void)
__OSX_AVAILABLE_BUT_DEPRECATED(__MAC_10_5,__MAC_10_7, __IPHONE_NA,__IPHONE_NA);


/* Deprecated. Use class_createInstance() instead. */
OBJC_EXPORT id objc_allocate_object(Class cls, int extra)
    AVAILABLE_MAC_OS_X_VERSION_10_4_AND_LATER_BUT_DEPRECATED;


/* !defined(OBJC_NO_GC) */
#else
/* defined(OBJC_NO_GC) */


/* Non-GC declarations */

static OBJC_INLINE void objc_collect(unsigned long options __unused) { }
static OBJC_INLINE BOOL objc_collectingEnabled(void) { return NO; }
static OBJC_INLINE void objc_setCollectionThreshold(size_t threshold __unused) { }
static OBJC_INLINE void objc_setCollectionRatio(size_t ratio __unused) { }
static OBJC_INLINE void objc_startCollectorThread(void) { }

#if TARGET_OS_WIN32
static OBJC_INLINE BOOL objc_atomicCompareAndSwapPtr(id predicate, id replacement, volatile id *objectLocation) 
    { void *original = InterlockedCompareExchangePointer((void * volatile *)objectLocation, (void *)replacement, (void *)predicate); return (original == predicate); }

static OBJC_INLINE BOOL objc_atomicCompareAndSwapPtrBarrier(id predicate, id replacement, volatile id *objectLocation) 
    { void *original = InterlockedCompareExchangePointer((void * volatile *)objectLocation, (void *)replacement, (void *)predicate); return (original == predicate); }
#else
static OBJC_INLINE BOOL objc_atomicCompareAndSwapPtr(id predicate, id replacement, volatile id *objectLocation) 
    { return OSAtomicCompareAndSwapPtr((void *)predicate, (void *)replacement, (void * volatile *)objectLocation); }

static OBJC_INLINE BOOL objc_atomicCompareAndSwapPtrBarrier(id predicate, id replacement, volatile id *objectLocation) 
    { return OSAtomicCompareAndSwapPtrBarrier((void *)predicate, (void *)replacement, (void * volatile *)objectLocation); }
#endif

static OBJC_INLINE BOOL objc_atomicCompareAndSwapGlobal(id predicate, id replacement, volatile id *objectLocation) 
    { return objc_atomicCompareAndSwapPtr(predicate, replacement, objectLocation); }

static OBJC_INLINE BOOL objc_atomicCompareAndSwapGlobalBarrier(id predicate, id replacement, volatile id *objectLocation) 
    { return objc_atomicCompareAndSwapPtrBarrier(predicate, replacement, objectLocation); }

static OBJC_INLINE BOOL objc_atomicCompareAndSwapInstanceVariable(id predicate, id replacement, volatile id *objectLocation) 
    { return objc_atomicCompareAndSwapPtr(predicate, replacement, objectLocation); }

static OBJC_INLINE BOOL objc_atomicCompareAndSwapInstanceVariableBarrier(id predicate, id replacement, volatile id *objectLocation) 
    { return objc_atomicCompareAndSwapPtrBarrier(predicate, replacement, objectLocation); }


static OBJC_INLINE id objc_assign_strongCast(id val, id *dest) 
    { return (*dest = val); }

static OBJC_INLINE id objc_assign_global(id val, id *dest) 
    { return (*dest = val); }

static OBJC_INLINE id objc_assign_ivar(id val, id dest, ptrdiff_t offset) 
    { return (*(id*)((char *)dest+offset) = val); }

static OBJC_INLINE void *objc_memmove_collectable(void *dst, const void *src, size_t size) 
    { return memmove(dst, src, size); }

static OBJC_INLINE id objc_read_weak(id *location) 
    { return *location; }

static OBJC_INLINE id objc_assign_weak(id value, id *location) 
    { return (*location = value); }

static OBJC_INLINE void objc_finalizeOnMainThread(Class cls __unused) { }
static OBJC_INLINE BOOL objc_is_finalized(void *ptr __unused) { return NO; }
static OBJC_INLINE void objc_clear_stack(unsigned long options __unused) { }

static OBJC_INLINE BOOL objc_collecting_enabled(void) { return NO; }
static OBJC_INLINE void objc_set_collection_threshold(size_t threshold __unused) { } 
static OBJC_INLINE void objc_set_collection_ratio(size_t ratio __unused) { } 
static OBJC_INLINE void objc_start_collector_thread(void) { }

OBJC_EXPORT id class_createInstance(Class cls, size_t extraBytes)
    __OSX_AVAILABLE_STARTING(__MAC_10_0, __IPHONE_2_0);
static OBJC_INLINE id objc_allocate_object(Class cls, int extra) 
    { return class_createInstance(cls, extra); }

static OBJC_INLINE void objc_registerThreadWithCollector() { }
static OBJC_INLINE void objc_unregisterThreadWithCollector() { }
static OBJC_INLINE void objc_assertRegisteredThreadWithCollector() { }

/* defined(OBJC_NO_GC) */
#endif


#if TARGET_OS_EMBEDDED
enum {
    OBJC_GENERATIONAL = (1 << 0)
};
static OBJC_INLINE void objc_collect_if_needed(unsigned long options) __attribute__((deprecated));
static OBJC_INLINE void objc_collect_if_needed(unsigned long options __unused) { }
#endif

#endif
Commit	Line	Data
2bfd4448	1	/*
b3962a83	2	* Copyright (c) 2004-2007 Apple Inc. All rights reserved.
2bfd4448 A	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
2bfd4448 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. Please obtain a copy of the License at
	10	* http://www.opensource.apple.com/apsl/ and read it before using this
	11	* file.
	12	*
	13	* The Original Code and all software distributed under the License are
	14	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	15	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	16	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	17	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	18	* Please see the License for the specific language governing rights and
	19	* limitations under the License.
	20	*
	21	* @APPLE_LICENSE_HEADER_END@
	22	*/
2bfd4448 A	23
	24	#ifndef _OBJC_AUTO_H_
	25	#define _OBJC_AUTO_H_
	26
7af964d1	27	#include <objc/objc.h>
8972963c	28	#include <malloc/malloc.h>
b3962a83	29	#include <stdint.h>
7af964d1 A	30	#include <stddef.h>
	31	#include <string.h>
	32	#include <Availability.h>
b3962a83	33	#include <AvailabilityMacros.h>
7af964d1 A	34	#include <TargetConditionals.h>
	35
	36	#if !TARGET_OS_WIN32
	37	#include <sys/types.h>
	38	#include <libkern/OSAtomic.h>
	39	#else
	40	# define WINVER 0x0501 // target Windows XP and later
	41	# define _WIN32_WINNT 0x0501 // target Windows XP and later
	42	# define WIN32_LEAN_AND_MEAN
	43	// workaround: windef.h typedefs BOOL as int
	44	# define BOOL WINBOOL
	45	# include <windows.h>
	46	# undef BOOL
	47	#endif
	48
	49
	50	/* GC is unsupported on some architectures. */
	51
8972963c	52	#if TARGET_OS_EMBEDDED \|\| TARGET_OS_IPHONE \|\| TARGET_OS_WIN32
7af964d1 A	53	# define OBJC_NO_GC 1
	54	#endif
	55
2bfd4448	56
7af964d1	57	/* objc_collect() options */
2bfd4448	58	enum {
b3962a83 A	59	// choose one
	60	OBJC_RATIO_COLLECTION = (0 << 0), // run "ratio" generational collections, then a full
	61	OBJC_GENERATIONAL_COLLECTION = (1 << 0), // run fast incremental collection
	62	OBJC_FULL_COLLECTION = (2 << 0), // run full collection.
	63	OBJC_EXHAUSTIVE_COLLECTION = (3 << 0), // run full collections until memory available stops improving
	64
	65	OBJC_COLLECT_IF_NEEDED = (1 << 3), // run collection only if needed (allocation threshold exceeded)
	66	OBJC_WAIT_UNTIL_DONE = (1 << 4), // wait (when possible) for collection to end before returning (when collector is running on dedicated thread)
2bfd4448 A	67	};
2bfd4448 A	68
7af964d1 A	69	/* objc_clear_stack() options */
	70	enum {
	71	OBJC_CLEAR_RESIDENT_STACK = (1 << 0)
	72	};
	73
8972963c	74	#ifndef OBJC_NO_GC
7af964d1	75
7af964d1	76
8972963c	77	/* GC declarations */
2bfd4448	78
8972963c A	79	/* Collection utilities */
	80
	81	OBJC_EXPORT void objc_collect(unsigned long options)
	82	__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA);
	83	OBJC_EXPORT BOOL objc_collectingEnabled(void)
	84	__OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);
	85	OBJC_EXPORT malloc_zone_t *objc_collectableZone(void)
	86	__OSX_AVAILABLE_STARTING(__MAC_10_7, __IPHONE_NA);
2bfd4448	87
b3962a83 A	88	/* GC configuration */
	89
	90	/* Tells collector to wait until specified bytes have been allocated before trying to collect again. */
8972963c A	91	OBJC_EXPORT void objc_setCollectionThreshold(size_t threshold)
8972963c A	92	__OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);
b3962a83 A	93
b3962a83 A	94	/* Tells collector to run a full collection for every ratio generational collections. */
8972963c A	95	OBJC_EXPORT void objc_setCollectionRatio(size_t ratio)
8972963c A	96	__OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);
b3962a83	97
8972963c A	98	//
	99	// GC-safe compare-and-swap
	100	//
b3962a83	101
7af964d1	102	/* Atomic update, with write barrier. */
8972963c A	103	OBJC_EXPORT BOOL objc_atomicCompareAndSwapPtr(id predicate, id replacement, volatile id *objectLocation)
8972963c A	104	__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;
7af964d1	105	/* "Barrier" version also includes memory barrier. */
8972963c A	106	OBJC_EXPORT BOOL objc_atomicCompareAndSwapPtrBarrier(id predicate, id replacement, volatile id *objectLocation)
8972963c A	107	__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;
b3962a83 A	108
b3962a83 A	109	// atomic update of a global variable
8972963c A	110	OBJC_EXPORT BOOL objc_atomicCompareAndSwapGlobal(id predicate, id replacement, volatile id *objectLocation)
	111	__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;
	112	OBJC_EXPORT BOOL objc_atomicCompareAndSwapGlobalBarrier(id predicate, id replacement, volatile id *objectLocation)
	113	__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;
b3962a83	114	// atomic update of an instance variable
8972963c A	115	OBJC_EXPORT BOOL objc_atomicCompareAndSwapInstanceVariable(id predicate, id replacement, volatile id *objectLocation)
	116	__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;
	117	OBJC_EXPORT BOOL objc_atomicCompareAndSwapInstanceVariableBarrier(id predicate, id replacement, volatile id *objectLocation)
	118	__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA) OBJC_ARC_UNAVAILABLE;
7af964d1	119
b3962a83	120
8972963c A	121	//
	122	// Read and write barriers
	123	//
2bfd4448	124
8972963c A	125	OBJC_EXPORT id objc_assign_strongCast(id val, id *dest)
	126	__OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_NA);
	127	OBJC_EXPORT id objc_assign_global(id val, id *dest)
	128	__OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_NA);
	129	OBJC_EXPORT id objc_assign_threadlocal(id val, id *dest)
	130	__OSX_AVAILABLE_STARTING(__MAC_10_7, __IPHONE_NA);
	131	OBJC_EXPORT id objc_assign_ivar(id value, id dest, ptrdiff_t offset)
	132	__OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_NA);
	133	OBJC_EXPORT void objc_memmove_collectable(void dst, const void *src, size_t size)
	134	__OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_NA);
	135
	136	OBJC_EXPORT id objc_read_weak(id *location)
	137	__OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);
	138	OBJC_EXPORT id objc_assign_weak(id value, id *location)
	139	__OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);
b3962a83 A	140
	141
	142	//
8972963c A	143	// Thread management
8972963c A	144	//
b3962a83	145
8972963c A	146	/* Register the calling thread with the garbage collector. */
	147	OBJC_EXPORT void objc_registerThreadWithCollector(void)
	148	__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA);
b3962a83	149
8972963c A	150	/* Unregisters the calling thread with the garbage collector.
	151	Unregistration also happens automatically at thread exit. */
	152	OBJC_EXPORT void objc_unregisterThreadWithCollector(void)
	153	__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA);
b3962a83	154
8972963c A	155	/* To be called from code which must only execute on a registered thread. */
	156	/* If the calling thread is unregistered then an error message is emitted and the thread is implicitly registered. */
	157	OBJC_EXPORT void objc_assertRegisteredThreadWithCollector(void)
	158	__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_NA);
	159
	160	/* Erases any stale references in unused parts of the stack. */
	161	OBJC_EXPORT void objc_clear_stack(unsigned long options)
	162	__OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);
b3962a83	163
b3962a83 A	164
b3962a83 A	165	//
8972963c A	166	// Finalization
8972963c A	167	//
b3962a83	168
8972963c A	169	/* Returns true if object has been scheduled for finalization. Can be used to avoid operations that may lead to resurrection, which are fatal. */
	170	OBJC_EXPORT BOOL objc_is_finalized(void *ptr)
	171	__OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_NA);
b3962a83	172
8972963c A	173	// Deprcated. Tells runtime to issue finalize calls on the main thread only.
	174	OBJC_EXPORT void objc_finalizeOnMainThread(Class cls)
	175	AVAILABLE_MAC_OS_X_VERSION_10_5_AND_LATER_BUT_DEPRECATED;
b3962a83	176
7af964d1	177
8972963c A	178	//
	179	// Deprecated names.
	180	//
	181
	182	/* Deprecated. Use objc_collectingEnabled() instead. */
	183	OBJC_EXPORT BOOL objc_collecting_enabled(void)
	184	__OSX_AVAILABLE_BUT_DEPRECATED(__MAC_10_4,__MAC_10_5, __IPHONE_NA,__IPHONE_NA);
	185	/* Deprecated. Use objc_setCollectionThreshold() instead. */
	186	OBJC_EXPORT void objc_set_collection_threshold(size_t threshold)
	187	__OSX_AVAILABLE_BUT_DEPRECATED(__MAC_10_4,__MAC_10_5, __IPHONE_NA,__IPHONE_NA);
	188	/* Deprecated. Use objc_setCollectionRatio() instead. */
	189	OBJC_EXPORT void objc_set_collection_ratio(size_t ratio)
	190	__OSX_AVAILABLE_BUT_DEPRECATED(__MAC_10_4,__MAC_10_5, __IPHONE_NA,__IPHONE_NA);
	191	/* Deprecated. Use objc_startCollectorThread() instead. */
	192	OBJC_EXPORT void objc_start_collector_thread(void)
	193	__OSX_AVAILABLE_BUT_DEPRECATED(__MAC_10_4,__MAC_10_5, __IPHONE_NA,__IPHONE_NA);
	194	/* Deprecated. No replacement. Formerly told the collector to run using a dedicated background thread. */
	195	OBJC_EXPORT void objc_startCollectorThread(void)
	196	__OSX_AVAILABLE_BUT_DEPRECATED(__MAC_10_5,__MAC_10_7, __IPHONE_NA,__IPHONE_NA);
	197
	198
	199	/* Deprecated. Use class_createInstance() instead. */
	200	OBJC_EXPORT id objc_allocate_object(Class cls, int extra)
	201	AVAILABLE_MAC_OS_X_VERSION_10_4_AND_LATER_BUT_DEPRECATED;
	202
	203
	204	/* !defined(OBJC_NO_GC) */
	205	#else
	206	/* defined(OBJC_NO_GC) */
7af964d1	207
7af964d1	208
8972963c	209	/* Non-GC declarations */
7af964d1	210
8972963c	211	static OBJC_INLINE void objc_collect(unsigned long options __unused) { }
7af964d1	212	static OBJC_INLINE BOOL objc_collectingEnabled(void) { return NO; }
8972963c A	213	static OBJC_INLINE void objc_setCollectionThreshold(size_t threshold __unused) { }
8972963c A	214	static OBJC_INLINE void objc_setCollectionRatio(size_t ratio __unused) { }
7af964d1 A	215	static OBJC_INLINE void objc_startCollectorThread(void) { }
	216
	217	#if TARGET_OS_WIN32
	218	static OBJC_INLINE BOOL objc_atomicCompareAndSwapPtr(id predicate, id replacement, volatile id *objectLocation)
	219	{ void original = InterlockedCompareExchangePointer((void volatile )objectLocation, (void )replacement, (void *)predicate); return (original == predicate); }
	220
	221	static OBJC_INLINE BOOL objc_atomicCompareAndSwapPtrBarrier(id predicate, id replacement, volatile id *objectLocation)
	222	{ void original = InterlockedCompareExchangePointer((void volatile )objectLocation, (void )replacement, (void *)predicate); return (original == predicate); }
	223	#else
	224	static OBJC_INLINE BOOL objc_atomicCompareAndSwapPtr(id predicate, id replacement, volatile id *objectLocation)
	225	{ return OSAtomicCompareAndSwapPtr((void )predicate, (void )replacement, (void * volatile *)objectLocation); }
	226
	227	static OBJC_INLINE BOOL objc_atomicCompareAndSwapPtrBarrier(id predicate, id replacement, volatile id *objectLocation)
	228	{ return OSAtomicCompareAndSwapPtrBarrier((void )predicate, (void )replacement, (void * volatile *)objectLocation); }
	229	#endif
	230
	231	static OBJC_INLINE BOOL objc_atomicCompareAndSwapGlobal(id predicate, id replacement, volatile id *objectLocation)
	232	{ return objc_atomicCompareAndSwapPtr(predicate, replacement, objectLocation); }
	233
	234	static OBJC_INLINE BOOL objc_atomicCompareAndSwapGlobalBarrier(id predicate, id replacement, volatile id *objectLocation)
	235	{ return objc_atomicCompareAndSwapPtrBarrier(predicate, replacement, objectLocation); }
	236
	237	static OBJC_INLINE BOOL objc_atomicCompareAndSwapInstanceVariable(id predicate, id replacement, volatile id *objectLocation)
	238	{ return objc_atomicCompareAndSwapPtr(predicate, replacement, objectLocation); }
	239
	240	static OBJC_INLINE BOOL objc_atomicCompareAndSwapInstanceVariableBarrier(id predicate, id replacement, volatile id *objectLocation)
	241	{ return objc_atomicCompareAndSwapPtrBarrier(predicate, replacement, objectLocation); }
b3962a83	242
2bfd4448	243
7af964d1 A	244	static OBJC_INLINE id objc_assign_strongCast(id val, id *dest)
	245	{ return (*dest = val); }
	246
	247	static OBJC_INLINE id objc_assign_global(id val, id *dest)
	248	{ return (*dest = val); }
	249
	250	static OBJC_INLINE id objc_assign_ivar(id val, id dest, ptrdiff_t offset)
	251	{ return ((id)((char *)dest+offset) = val); }
	252
	253	static OBJC_INLINE void objc_memmove_collectable(void dst, const void *src, size_t size)
	254	{ return memmove(dst, src, size); }
	255
	256	static OBJC_INLINE id objc_read_weak(id *location)
	257	{ return *location; }
	258
	259	static OBJC_INLINE id objc_assign_weak(id value, id *location)
	260	{ return (*location = value); }
	261
8972963c A	262	static OBJC_INLINE void objc_finalizeOnMainThread(Class cls __unused) { }
	263	static OBJC_INLINE BOOL objc_is_finalized(void *ptr __unused) { return NO; }
	264	static OBJC_INLINE void objc_clear_stack(unsigned long options __unused) { }
7af964d1 A	265
7af964d1 A	266	static OBJC_INLINE BOOL objc_collecting_enabled(void) { return NO; }
8972963c A	267	static OBJC_INLINE void objc_set_collection_threshold(size_t threshold __unused) { }
8972963c A	268	static OBJC_INLINE void objc_set_collection_ratio(size_t ratio __unused) { }
7af964d1 A	269	static OBJC_INLINE void objc_start_collector_thread(void) { }
7af964d1 A	270
8972963c A	271	OBJC_EXPORT id class_createInstance(Class cls, size_t extraBytes)
8972963c A	272	__OSX_AVAILABLE_STARTING(__MAC_10_0, __IPHONE_2_0);
7af964d1 A	273	static OBJC_INLINE id objc_allocate_object(Class cls, int extra)
	274	{ return class_createInstance(cls, extra); }
	275
	276	static OBJC_INLINE void objc_registerThreadWithCollector() { }
	277	static OBJC_INLINE void objc_unregisterThreadWithCollector() { }
	278	static OBJC_INLINE void objc_assertRegisteredThreadWithCollector() { }
	279
8972963c	280	/* defined(OBJC_NO_GC) */
7af964d1	281	#endif
8972963c A	282
	283
	284	#if TARGET_OS_EMBEDDED
	285	enum {
	286	OBJC_GENERATIONAL = (1 << 0)
	287	};
	288	static OBJC_INLINE void objc_collect_if_needed(unsigned long options) __attribute__((deprecated));
	289	static OBJC_INLINE void objc_collect_if_needed(unsigned long options __unused) { }
	290	#endif
	291
2bfd4448	292	#endif