1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * g_atomic_*: atomic operations.
5 * Copyright (C) 2003 Sebastian Wilhelmi
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
26 #include "gthreadprivate.h"
29 #if defined (__GNUC__)
30 # if defined (G_ATOMIC_I486)
31 /* Adapted from CVS version 1.10 of glibc's sysdeps/i386/i486/bits/atomic.h
34 g_atomic_int_exchange_and_add (volatile gint
*atomic
,
39 __asm__
__volatile__ ("lock; xaddl %0,%1"
40 : "=r" (result
), "=m" (*atomic
)
41 : "0" (val
), "m" (*atomic
));
46 g_atomic_int_add (volatile gint
*atomic
,
49 __asm__
__volatile__ ("lock; addl %1,%0"
51 : "ir" (val
), "m" (*atomic
));
55 g_atomic_int_compare_and_exchange (volatile gint
*atomic
,
61 __asm__
__volatile__ ("lock; cmpxchgl %2, %1"
62 : "=a" (result
), "=m" (*atomic
)
63 : "r" (newval
), "m" (*atomic
), "0" (oldval
));
65 return result
== oldval
;
68 /* The same code as above, as on i386 gpointer is 32 bit as well.
69 * Duplicating the code here seems more natural than casting the
70 * arguments and calling the former function */
73 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
79 __asm__
__volatile__ ("lock; cmpxchgl %2, %1"
80 : "=a" (result
), "=m" (*atomic
)
81 : "r" (newval
), "m" (*atomic
), "0" (oldval
));
83 return result
== oldval
;
86 # elif defined (G_ATOMIC_SPARCV9)
87 /* Adapted from CVS version 1.3 of glibc's sysdeps/sparc/sparc64/bits/atomic.h
89 # define ATOMIC_INT_CMP_XCHG(atomic, oldval, newval) \
92 __asm__ __volatile__ ("cas [%4], %2, %0" \
93 : "=r" (__result), "=m" (*(atomic)) \
94 : "r" (oldval), "m" (*(atomic)), "r" (atomic),\
99 # if GLIB_SIZEOF_VOID_P == 4 /* 32-bit system */
101 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
106 __asm__
__volatile__ ("cas [%4], %2, %0"
107 : "=r" (result
), "=m" (*atomic
)
108 : "r" (oldval
), "m" (*atomic
), "r" (atomic
),
110 return result
== oldval
;
112 # elif GLIB_SIZEOF_VOID_P == 8 /* 64-bit system */
114 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
119 gpointer
*a
= atomic
;
120 __asm__
__volatile__ ("casx [%4], %2, %0"
121 : "=r" (result
), "=m" (*a
)
122 : "r" (oldval
), "m" (*a
), "r" (a
),
124 return result
== oldval
;
126 # else /* What's that */
127 # error "Your system has an unsupported pointer size"
128 # endif /* GLIB_SIZEOF_VOID_P */
129 # define G_ATOMIC_MEMORY_BARRIER \
130 __asm__ __volatile__ ("membar #LoadLoad | #LoadStore" \
131 " | #StoreLoad | #StoreStore" : : : "memory")
133 # elif defined (G_ATOMIC_ALPHA)
134 /* Adapted from CVS version 1.3 of glibc's sysdeps/alpha/bits/atomic.h
136 # define ATOMIC_INT_CMP_XCHG(atomic, oldval, newval) \
140 __asm__ __volatile__ ( \
143 " cmpeq %0,%3,%1\n" \
158 # if GLIB_SIZEOF_VOID_P == 4 /* 32-bit system */
160 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
166 __asm__
__volatile__ (
184 # elif GLIB_SIZEOF_VOID_P == 8 /* 64-bit system */
186 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
192 __asm__
__volatile__ (
210 # else /* What's that */
211 # error "Your system has an unsupported pointer size"
212 # endif /* GLIB_SIZEOF_VOID_P */
213 # define G_ATOMIC_MEMORY_BARRIER __asm__ ("mb" : : : "memory")
214 # elif defined (G_ATOMIC_X86_64)
215 /* Adapted from CVS version 1.9 of glibc's sysdeps/x86_64/bits/atomic.h
218 g_atomic_int_exchange_and_add (volatile gint
*atomic
,
223 __asm__
__volatile__ ("lock; xaddl %0,%1"
224 : "=r" (result
), "=m" (*atomic
)
225 : "0" (val
), "m" (*atomic
));
230 g_atomic_int_add (volatile gint
*atomic
,
233 __asm__
__volatile__ ("lock; addl %1,%0"
235 : "ir" (val
), "m" (*atomic
));
239 g_atomic_int_compare_and_exchange (volatile gint
*atomic
,
245 __asm__
__volatile__ ("lock; cmpxchgl %2, %1"
246 : "=a" (result
), "=m" (*atomic
)
247 : "r" (newval
), "m" (*atomic
), "0" (oldval
));
249 return result
== oldval
;
253 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
259 __asm__
__volatile__ ("lock; cmpxchgq %q2, %1"
260 : "=a" (result
), "=m" (*atomic
)
261 : "r" (newval
), "m" (*atomic
), "0" (oldval
));
263 return result
== oldval
;
266 # elif defined (G_ATOMIC_POWERPC)
267 /* Adapted from CVS version 1.16 of glibc's sysdeps/powerpc/bits/atomic.h
268 * and CVS version 1.4 of glibc's sysdeps/powerpc/powerpc32/bits/atomic.h
269 * and CVS version 1.7 of glibc's sysdeps/powerpc/powerpc64/bits/atomic.h
272 /* Non-optimizing compile bails on the following two asm statements
273 * for reasons unknown to the author */
275 g_atomic_int_exchange_and_add (volatile gint
*atomic
,
279 __asm__
__volatile__ ("1: lwarx %0,0,%3\n"
283 : "=&b" (result
), "=&r" (temp
), "=m" (*atomic
)
284 : "b" (atomic
), "r" (val
), "m" (*atomic
)
289 /* The same as above, to save a function call repeated here */
291 g_atomic_int_add (volatile gint
*atomic
,
295 __asm__
__volatile__ ("1: lwarx %0,0,%3\n"
299 : "=&b" (result
), "=&r" (temp
), "=m" (*atomic
)
300 : "b" (atomic
), "r" (val
), "m" (*atomic
)
303 # else /* !__OPTIMIZE__ */
305 g_atomic_int_exchange_and_add (volatile gint
*atomic
,
311 while (!g_atomic_int_compare_and_exchange (atomic
, result
, result
+ val
));
317 g_atomic_int_add (volatile gint
*atomic
,
323 while (!g_atomic_int_compare_and_exchange (atomic
, result
, result
+ val
));
325 # endif /* !__OPTIMIZE__ */
327 # if GLIB_SIZEOF_VOID_P == 4 /* 32-bit system */
329 g_atomic_int_compare_and_exchange (volatile gint
*atomic
,
334 __asm__
__volatile__ ("sync\n"
342 : "b" (atomic
), "r" (oldval
), "r" (newval
)
348 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
353 __asm__
__volatile__ ("sync\n"
361 : "b" (atomic
), "r" (oldval
), "r" (newval
)
365 # elif GLIB_SIZEOF_VOID_P == 8 /* 64-bit system */
367 g_atomic_int_compare_and_exchange (volatile gint
*atomic
,
372 __asm__
__volatile__ ("sync\n"
381 : "b" (atomic
), "r" (oldval
), "r" (newval
)
387 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
392 __asm__
__volatile__ ("sync\n"
400 : "b" (atomic
), "r" (oldval
), "r" (newval
)
404 # else /* What's that */
405 # error "Your system has an unsupported pointer size"
406 # endif /* GLIB_SIZEOF_VOID_P */
408 # define G_ATOMIC_MEMORY_BARRIER __asm__ ("sync" : : : "memory")
410 # elif defined (G_ATOMIC_IA64)
411 /* Adapted from CVS version 1.8 of glibc's sysdeps/ia64/bits/atomic.h
414 g_atomic_int_exchange_and_add (volatile gint
*atomic
,
417 return __sync_fetch_and_add (atomic
, val
);
421 g_atomic_int_add (volatile gint
*atomic
,
424 __sync_fetch_and_add (atomic
, val
);
428 g_atomic_int_compare_and_exchange (volatile gint
*atomic
,
432 return __sync_bool_compare_and_swap (atomic
, oldval
, newval
);
436 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
440 return __sync_bool_compare_and_swap ((long *)atomic
,
441 (long)oldval
, (long)newval
);
444 # define G_ATOMIC_MEMORY_BARRIER __sync_synchronize ()
445 # elif defined (G_ATOMIC_S390)
446 /* Adapted from glibc's sysdeps/s390/bits/atomic.h
448 # define ATOMIC_INT_CMP_XCHG(atomic, oldval, newval) \
450 gint __result = oldval; \
451 __asm__ __volatile__ ("cs %0, %2, %1" \
452 : "+d" (__result), "=Q" (*(atomic)) \
453 : "d" (newval), "m" (*(atomic)) : "cc" ); \
454 __result == oldval; \
457 # if GLIB_SIZEOF_VOID_P == 4 /* 32-bit system */
459 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
463 gpointer result
= oldval
;
464 __asm__
__volatile__ ("cs %0, %2, %1"
465 : "+d" (result
), "=Q" (*(atomic
))
466 : "d" (newval
), "m" (*(atomic
)) : "cc" );
467 return result
== oldval
;
469 # elif GLIB_SIZEOF_VOID_P == 8 /* 64-bit system */
471 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
475 gpointer result
= oldval
;
476 gpointer
*a
= atomic
;
477 __asm__
__volatile__ ("csg %0, %2, %1"
478 : "+d" (result
), "=Q" (*a
)
479 : "d" ((long)(newval
)), "m" (*a
) : "cc" );
480 return result
== oldval
;
482 # else /* What's that */
483 # error "Your system has an unsupported pointer size"
484 # endif /* GLIB_SIZEOF_VOID_P */
485 # else /* !G_ATOMIC_IA64 */
486 # define DEFINE_WITH_MUTEXES
487 # endif /* G_ATOMIC_IA64 */
488 #else /* !__GNUC__ */
489 # ifdef G_PLATFORM_WIN32
490 # define DEFINE_WITH_WIN32_INTERLOCKED
492 # define DEFINE_WITH_MUTEXES
494 #endif /* __GNUC__ */
496 #ifdef DEFINE_WITH_WIN32_INTERLOCKED
497 # include <windows.h>
498 /* Following indicates that InterlockedCompareExchangePointer is
499 * declared in winbase.h (included by windows.h) and needs to be
500 * commented out if not true. It is defined iff WINVER > 0x0400,
501 * which is usually correct but can be wrong if WINVER is set before
502 * windows.h is included.
505 # define HAVE_INTERLOCKED_COMPARE_EXCHANGE_POINTER
509 g_atomic_int_exchange_and_add (volatile gint32
*atomic
,
512 return InterlockedExchangeAdd (atomic
, val
);
516 g_atomic_int_add (volatile gint32
*atomic
,
519 InterlockedExchangeAdd (atomic
, val
);
523 g_atomic_int_compare_and_exchange (volatile gint32
*atomic
,
527 #ifndef HAVE_INTERLOCKED_COMPARE_EXCHANGE_POINTER
528 return (guint32
) InterlockedCompareExchange ((PVOID
*)atomic
,
530 (PVOID
)oldval
) == oldval
;
532 return InterlockedCompareExchange (atomic
,
539 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
543 # ifdef HAVE_INTERLOCKED_COMPARE_EXCHANGE_POINTER
544 return InterlockedCompareExchangePointer (atomic
, newval
, oldval
) == oldval
;
546 # if GLIB_SIZEOF_VOID_P != 4 /* no 32-bit system */
547 # error "InterlockedCompareExchangePointer needed"
549 return InterlockedCompareExchange (atomic
, newval
, oldval
) == oldval
;
553 #endif /* DEFINE_WITH_WIN32_INTERLOCKED */
555 #ifdef DEFINE_WITH_MUTEXES
556 /* We have to use the slow, but safe locking method */
557 static GMutex
*g_atomic_mutex
;
560 g_atomic_int_exchange_and_add (volatile gint
*atomic
,
565 g_mutex_lock (g_atomic_mutex
);
568 g_mutex_unlock (g_atomic_mutex
);
575 g_atomic_int_add (volatile gint
*atomic
,
578 g_mutex_lock (g_atomic_mutex
);
580 g_mutex_unlock (g_atomic_mutex
);
584 g_atomic_int_compare_and_exchange (volatile gint
*atomic
,
590 g_mutex_lock (g_atomic_mutex
);
591 if (*atomic
== oldval
)
598 g_mutex_unlock (g_atomic_mutex
);
604 g_atomic_pointer_compare_and_exchange (volatile gpointer
*atomic
,
610 g_mutex_lock (g_atomic_mutex
);
611 if (*atomic
== oldval
)
618 g_mutex_unlock (g_atomic_mutex
);
623 #ifdef G_ATOMIC_OP_MEMORY_BARRIER_NEEDED
625 g_atomic_int_get (volatile gint
*atomic
)
629 g_mutex_lock (g_atomic_mutex
);
631 g_mutex_unlock (g_atomic_mutex
);
637 g_atomic_int_set (volatile gint
*atomic
,
640 g_mutex_lock (g_atomic_mutex
);
642 g_mutex_unlock (g_atomic_mutex
);
646 g_atomic_pointer_get (volatile gpointer
*atomic
)
650 g_mutex_lock (g_atomic_mutex
);
652 g_mutex_unlock (g_atomic_mutex
);
658 g_atomic_pointer_set (volatile gpointer
*atomic
,
661 g_mutex_lock (g_atomic_mutex
);
663 g_mutex_unlock (g_atomic_mutex
);
665 #endif /* G_ATOMIC_OP_MEMORY_BARRIER_NEEDED */
666 #elif defined (G_ATOMIC_OP_MEMORY_BARRIER_NEEDED)
668 g_atomic_int_get (volatile gint
*atomic
)
670 G_ATOMIC_MEMORY_BARRIER
;
675 g_atomic_int_set (volatile gint
*atomic
,
679 G_ATOMIC_MEMORY_BARRIER
;
683 g_atomic_pointer_get (volatile gpointer
*atomic
)
685 G_ATOMIC_MEMORY_BARRIER
;
690 g_atomic_pointer_set (volatile gpointer
*atomic
,
694 G_ATOMIC_MEMORY_BARRIER
;
696 #endif /* DEFINE_WITH_MUTEXES || G_ATOMIC_OP_MEMORY_BARRIER_NEEDED */
698 #ifdef ATOMIC_INT_CMP_XCHG
700 g_atomic_int_compare_and_exchange (volatile gint
*atomic
,
704 return ATOMIC_INT_CMP_XCHG (atomic
, oldval
, newval
);
708 g_atomic_int_exchange_and_add (volatile gint
*atomic
,
714 while (!ATOMIC_INT_CMP_XCHG (atomic
, result
, result
+ val
));
720 g_atomic_int_add (volatile gint
*atomic
,
726 while (!ATOMIC_INT_CMP_XCHG (atomic
, result
, result
+ val
));
728 #endif /* ATOMIC_INT_CMP_XCHG */
731 _g_atomic_thread_init (void)
733 #ifdef DEFINE_WITH_MUTEXES
734 g_atomic_mutex
= g_mutex_new ();
735 #endif /* DEFINE_WITH_MUTEXES */
738 #ifndef G_ATOMIC_OP_MEMORY_BARRIER_NEEDED
740 (g_atomic_int_get
) (volatile gint
*atomic
)
742 return g_atomic_int_get (atomic
);
746 (g_atomic_int_set
) (volatile gint
*atomic
,
749 g_atomic_int_set (atomic
, newval
);
753 (g_atomic_pointer_get
) (volatile gpointer
*atomic
)
755 return g_atomic_pointer_get (atomic
);
759 (g_atomic_pointer_set
) (volatile gpointer
*atomic
,
762 g_atomic_pointer_set (atomic
, newval
);
764 #endif /* G_ATOMIC_OP_MEMORY_BARRIER_NEEDED */
766 #define __G_ATOMIC_C__
767 #include "galiasdef.c"