Mercurial > sdl-ios-xcode

annotate include/SDL_atomic.h @ 5241:c7be6ca3a0b8

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Fixed crash when shaders are not supported
author Sam Lantinga <slouken@libsdl.org>
date Wed, 09 Feb 2011 09:36:40 -0800
parents 5d01d426f2ea
children b530ef003506
rev   line source
3180
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
1 /*
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
2 SDL - Simple DirectMedia Layer
3697
f7b03b6838cb Fixed bug #926
Sam Lantinga <slouken@libsdl.org>
parents: 3407
diff changeset
3 Copyright (C) 1997-2010 Sam Lantinga
3180
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
4
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
5 This library is free software; you can redistribute it and/or
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
6 modify it under the terms of the GNU Lesser General Public
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
7 License as published by the Free Software Foundation; either
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
8 version 2.1 of the License, or (at your option) any later version.
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
9
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
10 This library is distributed in the hope that it will be useful,
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
13 Lesser General Public License for more details.
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
14
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
15 You should have received a copy of the GNU Lesser General Public
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
16 License along with this library; if not, write to the Free Software
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
18
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
19 Sam Lantinga
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
20 slouken@libsdl.org
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
21 */
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
22
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
23 /**
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
24 * \file SDL_atomic.h
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
25 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
26 * Atomic operations.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
27 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
28 * IMPORTANT:
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
29 * If you are not an expert in concurrent lockless programming, you should
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
30 * only be using the atomic lock and reference counting functions in this
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
31 * file. In all other cases you should be protecting your data structures
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
32 * with full mutexes.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
33 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
34 * The list of "safe" functions to use are:
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
35 * SDL_AtomicLock()
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
36 * SDL_AtomicUnlock()
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
37 * SDL_AtomicIncRef()
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
38 * SDL_AtomicDecRef()
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
39 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
40 * Seriously, here be dragons!
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
41 * ^^^^^^^^^^^^^^^^^^^^^^^^^^^
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
42 *
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
43 * You can find out a little more about lockless programming and the
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
44 * subtle issues that can arise here:
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
45 * http://msdn.microsoft.com/en-us/library/ee418650%28v=vs.85%29.aspx
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
46 *
5100
470ede30189c Added a FIFO test to the atomic test suite.
Sam Lantinga <slouken@libsdl.org>
parents: 5099
diff changeset
47 * There's also lots of good information here:
470ede30189c Added a FIFO test to the atomic test suite.
Sam Lantinga <slouken@libsdl.org>
parents: 5099
diff changeset
48 * http://www.1024cores.net/home/lock-free-algorithms
470ede30189c Added a FIFO test to the atomic test suite.
Sam Lantinga <slouken@libsdl.org>
parents: 5099
diff changeset
49 *
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
50 * These operations may or may not actually be implemented using
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
51 * processor specific atomic operations. When possible they are
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
52 * implemented as true processor specific atomic operations. When that
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
53 * is not possible the are implemented using locks that *do* use the
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
54 * available atomic operations.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
55 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
56 * All of the atomic operations that modify memory are full memory barriers.
3180
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
57 */
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
58
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
59 #ifndef _SDL_atomic_h_
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
60 #define _SDL_atomic_h_
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
61
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
62 #include "SDL_stdinc.h"
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
63 #include "SDL_platform.h"
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
64
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
65 #include "begin_code.h"
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
66
5073
1e94e68525d5 Fixed bug #1097
Sam Lantinga <slouken@libsdl.org>
parents: 5024
diff changeset
67 /* Need to do this here because intrin.h has C++ code in it */
1e94e68525d5 Fixed bug #1097
Sam Lantinga <slouken@libsdl.org>
parents: 5024
diff changeset
68 /* Visual Studio 2005 has a bug where intrin.h conflicts with winnt.h */
5088
c2539ff054c8 Fixed compiling on Windows Mobile SDK 5.0 with Visual Studio 2008
Sam Lantinga <slouken@libsdl.org>
parents: 5073
diff changeset
69 #if defined(_MSC_VER) && (_MSC_VER >= 1500) && !defined(_WIN32_WCE)
5073
1e94e68525d5 Fixed bug #1097
Sam Lantinga <slouken@libsdl.org>
parents: 5024
diff changeset
70 #include <intrin.h>
5098
e4301cde4de1 Fixed compile error on Visual C++
Sam Lantinga <slouken@libsdl.org>
parents: 5097
diff changeset
71 #define HAVE_MSC_ATOMICS 1
5073
1e94e68525d5 Fixed bug #1097
Sam Lantinga <slouken@libsdl.org>
parents: 5024
diff changeset
72 #endif
1e94e68525d5 Fixed bug #1097
Sam Lantinga <slouken@libsdl.org>
parents: 5024
diff changeset
73
3180
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
74 /* Set up for C function definitions, even when using C++ */
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
75 #ifdef __cplusplus
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
76 /* *INDENT-OFF* */
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
77 extern "C" {
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
78 /* *INDENT-ON* */
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
79 #endif
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
80
3261
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
81 /**
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
82 * \name SDL AtomicLock
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
83 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
84 * The atomic locks are efficient spinlocks using CPU instructions,
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
85 * but are vulnerable to starvation and can spin forever if a thread
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
86 * holding a lock has been terminated. For this reason you should
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
87 * minimize the code executed inside an atomic lock and never do
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
88 * expensive things like API or system calls while holding them.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
89 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
90 * The atomic locks are not safe to lock recursively.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
91 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
92 * Porting Note:
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
93 * The spin lock functions and type are required and can not be
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
94 * emulated because they are used in the atomic emulation code.
3261
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
95 */
3407
d3baf5ac4e37 Partial fix for bug #859
Sam Lantinga <slouken@libsdl.org>
parents: 3261
diff changeset
96 /*@{*/
3261
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
97
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
98 typedef int SDL_SpinLock;
3261
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
99
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
100 /**
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
101 * \brief Try to lock a spin lock by setting it to a non-zero value.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
102 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
103 * \param lock Points to the lock.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
104 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
105 * \return SDL_TRUE if the lock succeeded, SDL_FALSE if the lock is already held.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
106 */
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
107 extern DECLSPEC SDL_bool SDLCALL SDL_AtomicTryLock(SDL_SpinLock *lock);
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
108
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
109 /**
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
110 * \brief Lock a spin lock by setting it to a non-zero value.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
111 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
112 * \param lock Points to the lock.
3261
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
113 */
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
114 extern DECLSPEC void SDLCALL SDL_AtomicLock(SDL_SpinLock *lock);
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
115
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
116 /**
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
117 * \brief Unlock a spin lock by setting it to 0. Always returns immediately
3261
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
118 *
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
119 * \param lock Points to the lock.
3261
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
120 */
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
121 extern DECLSPEC void SDLCALL SDL_AtomicUnlock(SDL_SpinLock *lock);
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops.
Bob Pendleton <bob@pendleton.com>
parents: 3237
diff changeset
122
3407
d3baf5ac4e37 Partial fix for bug #859
Sam Lantinga <slouken@libsdl.org>
parents: 3261
diff changeset
123 /*@}*//*SDL AtomicLock*/
3202
3aa519a5c676 I've made so many changes I don't dare continue until I check the current stuff in.
Bob Pendleton <bob@pendleton.com>
parents: 3199
diff changeset
124
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
125
5138
aee04c635ec6 Tweak for documentation
Sam Lantinga <slouken@libsdl.org>
parents: 5100
diff changeset
126 /**
aee04c635ec6 Tweak for documentation
Sam Lantinga <slouken@libsdl.org>
parents: 5100
diff changeset
127 * The compiler barrier prevents the compiler from reordering
aee04c635ec6 Tweak for documentation
Sam Lantinga <slouken@libsdl.org>
parents: 5100
diff changeset
128 * reads and writes to globally visible variables across the call.
aee04c635ec6 Tweak for documentation
Sam Lantinga <slouken@libsdl.org>
parents: 5100
diff changeset
129 */
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
130 #ifdef _MSC_VER
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
131 void _ReadWriteBarrier(void);
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
132 #pragma intrinsic(_ReadWriteBarrier)
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
133 #define SDL_CompilerBarrier() _ReadWriteBarrier()
5099
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
134 #elif defined(__GNUC__)
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
135 #define SDL_CompilerBarrier() __asm__ __volatile__ ("" : : : "memory")
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
136 #else
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
137 #define SDL_CompilerBarrier() \
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
138 ({ SDL_SpinLock _tmp = 0; SDL_AtomicLock(&_tmp); SDL_AtomicUnlock(&_tmp); })
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
139 #endif
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
140
5006
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h
Sam Lantinga <slouken@libsdl.org>
parents: 5005
diff changeset
141 /* Platform specific optimized versions of the atomic functions,
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h
Sam Lantinga <slouken@libsdl.org>
parents: 5005
diff changeset
142 * you can disable these by defining SDL_DISABLE_ATOMIC_INLINE
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h
Sam Lantinga <slouken@libsdl.org>
parents: 5005
diff changeset
143 */
5230
5d01d426f2ea It's now possible to disable the fast atomic operations, at a huge performance penalty.
Sam Lantinga <slouken@libsdl.org>
parents: 5139
diff changeset
144 #if SDL_ATOMIC_DISABLED
5d01d426f2ea It's now possible to disable the fast atomic operations, at a huge performance penalty.
Sam Lantinga <slouken@libsdl.org>
parents: 5139
diff changeset
145 #define SDL_DISABLE_ATOMIC_INLINE
5d01d426f2ea It's now possible to disable the fast atomic operations, at a huge performance penalty.
Sam Lantinga <slouken@libsdl.org>
parents: 5139
diff changeset
146 #endif
5006
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h
Sam Lantinga <slouken@libsdl.org>
parents: 5005
diff changeset
147 #ifndef SDL_DISABLE_ATOMIC_INLINE
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h
Sam Lantinga <slouken@libsdl.org>
parents: 5005
diff changeset
148
5099
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
149 #ifdef HAVE_MSC_ATOMICS
5004
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
150
5016
cc879bc6c4cf Fixed compiler warnings using Windows intrinsics
Sam Lantinga <slouken@libsdl.org>
parents: 5012
diff changeset
151 #define SDL_AtomicSet(a, v) _InterlockedExchange((long*)&(a)->value, (v))
cc879bc6c4cf Fixed compiler warnings using Windows intrinsics
Sam Lantinga <slouken@libsdl.org>
parents: 5012
diff changeset
152 #define SDL_AtomicAdd(a, v) _InterlockedExchangeAdd((long*)&(a)->value, (v))
cc879bc6c4cf Fixed compiler warnings using Windows intrinsics
Sam Lantinga <slouken@libsdl.org>
parents: 5012
diff changeset
153 #define SDL_AtomicCAS(a, oldval, newval) (_InterlockedCompareExchange((long*)&(a)->value, (newval), (oldval)) == (oldval))
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
154 #define SDL_AtomicSetPtr(a, v) _InterlockedExchangePointer((a), (v))
5012
2e282002bac3 Use compiler intrinsics, where available
Sam Lantinga <slouken@libsdl.org>
parents: 5006
diff changeset
155 #if _M_IX86
2e282002bac3 Use compiler intrinsics, where available
Sam Lantinga <slouken@libsdl.org>
parents: 5006
diff changeset
156 #define SDL_AtomicCASPtr(a, oldval, newval) (_InterlockedCompareExchange((long*)(a), (long)(newval), (long)(oldval)) == (long)(oldval))
2e282002bac3 Use compiler intrinsics, where available
Sam Lantinga <slouken@libsdl.org>
parents: 5006
diff changeset
157 #else
2e282002bac3 Use compiler intrinsics, where available
Sam Lantinga <slouken@libsdl.org>
parents: 5006
diff changeset
158 #define SDL_AtomicCASPtr(a, oldval, newval) (_InterlockedCompareExchangePointer((a), (newval), (oldval)) == (oldval))
2e282002bac3 Use compiler intrinsics, where available
Sam Lantinga <slouken@libsdl.org>
parents: 5006
diff changeset
159 #endif
5004
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
160
5099
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
161 #elif defined(__MACOSX__)
5004
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
162 #include <libkern/OSAtomic.h>
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
163
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
164 #define SDL_AtomicCAS(a, oldval, newval) OSAtomicCompareAndSwap32Barrier((oldval), (newval), &(a)->value)
5004
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
165 #if SIZEOF_VOIDP == 4
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
166 #define SDL_AtomicCASPtr(a, oldval, newval) OSAtomicCompareAndSwap32Barrier((int32_t)(oldval), (int32_t)(newval), (int32_t*)(a))
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
167 #elif SIZEOF_VOIDP == 8
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
168 #define SDL_AtomicCASPtr(a, oldval, newval) OSAtomicCompareAndSwap64Barrier((int64_t)(oldval), (int64_t)(newval), (int64_t*)(a))
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
169 #endif
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
170
5099
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
171 #elif defined(HAVE_GCC_ATOMICS)
5004
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
172
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
173 #define SDL_AtomicSet(a, v) __sync_lock_test_and_set(&(a)->value, v)
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
174 #define SDL_AtomicAdd(a, v) __sync_fetch_and_add(&(a)->value, v)
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
175 #define SDL_AtomicSetPtr(a, v) __sync_lock_test_and_set(a, v)
5004
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
176 #define SDL_AtomicCAS(a, oldval, newval) __sync_bool_compare_and_swap(&(a)->value, oldval, newval)
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
177 #define SDL_AtomicCASPtr(a, oldval, newval) __sync_bool_compare_and_swap(a, oldval, newval)
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
178
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
179 #endif
3407
d3baf5ac4e37 Partial fix for bug #859
Sam Lantinga <slouken@libsdl.org>
parents: 3261
diff changeset
180
5006
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h
Sam Lantinga <slouken@libsdl.org>
parents: 5005
diff changeset
181 #endif /* !SDL_DISABLE_ATOMIC_INLINE */
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h
Sam Lantinga <slouken@libsdl.org>
parents: 5005
diff changeset
182
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h
Sam Lantinga <slouken@libsdl.org>
parents: 5005
diff changeset
183
3407
d3baf5ac4e37 Partial fix for bug #859
Sam Lantinga <slouken@libsdl.org>
parents: 3261
diff changeset
184 /**
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
185 * \brief A type representing an atomic integer value. It is a struct
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
186 * so people don't accidentally use numeric operations on it.
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
187 */
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
188 #ifndef SDL_atomic_t_defined
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
189 typedef struct { int value; } SDL_atomic_t;
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
190 #endif
3237
916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files.
Bob Pendleton <bob@pendleton.com>
parents: 3216
diff changeset
191
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
192 /**
5099
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
193 * \brief Set an atomic variable to a new value if it is currently an old value.
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
194 *
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
195 * \return SDL_TRUE if the atomic variable was set, SDL_FALSE otherwise.
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
196 *
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
197 * \note If you don't know what this function is for, you shouldn't use it!
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
198 */
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
199 #ifndef SDL_AtomicCAS
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
200 #define SDL_AtomicCAS SDL_AtomicCAS_
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
201 #endif
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
202 extern DECLSPEC SDL_bool SDLCALL SDL_AtomicCAS_(SDL_atomic_t *a, int oldval, int newval);
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
203
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
204 /**
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
205 * \brief Set an atomic variable to a value.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
206 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
207 * \return The previous value of the atomic variable.
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
208 */
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
209 #ifndef SDL_AtomicSet
5099
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
210 static __inline__ int SDL_AtomicSet(SDL_atomic_t *a, int v)
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
211 {
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
212 int value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
213 do {
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
214 value = a->value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
215 } while (!SDL_AtomicCAS(a, value, v));
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
216 return value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
217 }
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
218 #endif
3237
916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files.
Bob Pendleton <bob@pendleton.com>
parents: 3216
diff changeset
219
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
220 /**
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
221 * \brief Get the value of an atomic variable
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
222 */
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
223 #ifndef SDL_AtomicGet
5099
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
224 static __inline__ int SDL_AtomicGet(SDL_atomic_t *a)
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
225 {
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
226 int value = a->value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
227 SDL_CompilerBarrier();
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
228 return value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
229 }
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
230 #endif
3237
916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files.
Bob Pendleton <bob@pendleton.com>
parents: 3216
diff changeset
231
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
232 /**
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
233 * \brief Add to an atomic variable.
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
234 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
235 * \return The previous value of the atomic variable.
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
236 *
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
237 * \note This same style can be used for any number operation
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
238 */
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
239 #ifndef SDL_AtomicAdd
5099
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
240 static __inline__ int SDL_AtomicAdd(SDL_atomic_t *a, int v)
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
241 {
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
242 int value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
243 do {
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
244 value = a->value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
245 } while (!SDL_AtomicCAS(a, value, (value + v)));
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
246 return value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
247 }
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
248 #endif
3237
916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files.
Bob Pendleton <bob@pendleton.com>
parents: 3216
diff changeset
249
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
250 /**
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
251 * \brief Increment an atomic variable used as a reference count.
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
252 */
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
253 #ifndef SDL_AtomicIncRef
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
254 #define SDL_AtomicIncRef(a) SDL_AtomicAdd(a, 1)
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
255 #endif
3237
916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files.
Bob Pendleton <bob@pendleton.com>
parents: 3216
diff changeset
256
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
257 /**
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
258 * \brief Decrement an atomic variable used as a reference count.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
259 *
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
260 * \return SDL_TRUE if the variable reached zero after decrementing,
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
261 * SDL_FALSE otherwise
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
262 */
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
263 #ifndef SDL_AtomicDecRef
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
264 #define SDL_AtomicDecRef(a) (SDL_AtomicAdd(a, -1) == 1)
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
265 #endif
3237
916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files.
Bob Pendleton <bob@pendleton.com>
parents: 3216
diff changeset
266
3199
3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form.
Bob Pendleton <bob@pendleton.com>
parents: 3187
diff changeset
267 /**
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
268 * \brief Set a pointer to a new value if it is currently an old value.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
269 *
5004
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
270 * \return SDL_TRUE if the pointer was set, SDL_FALSE otherwise.
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
271 *
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
272 * \note If you don't know what this function is for, you shouldn't use it!
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
273 */
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
274 #ifndef SDL_AtomicCASPtr
5097
dceec93471e7 Improvements based on feedback from Anthony Williams
Sam Lantinga <slouken@libsdl.org>
parents: 5088
diff changeset
275 #define SDL_AtomicCASPtr SDL_AtomicCASPtr_
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents: 4474
diff changeset
276 #endif
5139
1a47d41912ff Spacing for documentation tweaks
Sam Lantinga <slouken@libsdl.org>
parents: 5138
diff changeset
277 extern DECLSPEC SDL_bool SDLCALL SDL_AtomicCASPtr_(void* *a, void *oldval, void *newval);
3407
d3baf5ac4e37 Partial fix for bug #859
Sam Lantinga <slouken@libsdl.org>
parents: 3261
diff changeset
278
5099
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
279 /**
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
280 * \brief Set a pointer to a value atomically.
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
281 *
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
282 * \return The previous value of the pointer.
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
283 */
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
284 #ifndef SDL_AtomicSetPtr
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
285 static __inline__ void* SDL_AtomicSetPtr(void* *a, void* v)
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
286 {
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
287 void* value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
288 do {
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
289 value = *a;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
290 } while (!SDL_AtomicCASPtr(a, value, v));
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
291 return value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
292 }
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
293 #endif
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
294
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
295 /**
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
296 * \brief Get the value of a pointer atomically.
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
297 */
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
298 #ifndef SDL_AtomicGetPtr
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
299 static __inline__ void* SDL_AtomicGetPtr(void* *a)
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
300 {
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
301 void* value = *a;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
302 SDL_CompilerBarrier();
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
303 return value;
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
304 }
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
305 #endif
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
306
b938ad843e52 More fixes for compilation on Visual Studio
Sam Lantinga <slouken@libsdl.org>
parents: 5098
diff changeset
307
3180
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
308 /* Ends C function definitions when using C++ */
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
309 #ifdef __cplusplus
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
310 /* *INDENT-OFF* */
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
311 }
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
312 /* *INDENT-ON* */
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
313 #endif
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
314
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
315 #include "close_code.h"
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
316
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
317 #endif /* _SDL_atomic_h_ */
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
318
77d6336711fc First commit for SDL atomic operations.
Bob Pendleton <bob@pendleton.com>
parents:
diff changeset
319 /* vi: set ts=4 sw=4 expandtab: */