]> git.sesse.net Git - vlc/blobdiff - include/vlc_atomic.h
libvlc_MetaRequest: increment item i_preparse_depth
[vlc] / include / vlc_atomic.h
index 1a05d45f7c9136218bbc1453c402c7596460646d..af88eabb5e7af12d38e78ae972db728d496aa68f 100644 (file)
@@ -32,9 +32,7 @@
 /*** Native C11 atomics ***/
 #  include <stdatomic.h>
 
-# elif defined (__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)
-
-/*** Intel/GCC atomics ***/
+# else
 
 #  define ATOMIC_FLAG_INIT false
 
  * unsigned equivalents, i.e. 4-bytes and 8-bytes types, although GCC also
  * supports 1 and 2-bytes types. Some non-x86 architectures do not support
  * 8-byte atomic types (or not efficiently). */
+#  if defined (_MSC_VER)
+/* Some atomic operations of the Interlocked API are only
+   available for desktop apps. Thus we define the atomic types to
+   be at least 32 bits wide. */
+typedef      int_least32_t atomic_flag;
+typedef      int_least32_t atomic_bool;
+typedef      int_least32_t atomic_char;
+typedef      int_least32_t atomic_schar;
+typedef     uint_least32_t atomic_uchar;
+typedef      int_least32_t atomic_short;
+typedef     uint_least32_t atomic_ushort;
+#  else
 typedef          bool      atomic_flag;
 typedef          bool      atomic_bool;
 typedef          char      atomic_char;
@@ -66,6 +76,7 @@ typedef   signed char      atomic_schar;
 typedef unsigned char      atomic_uchar;
 typedef          short     atomic_short;
 typedef unsigned short     atomic_ushort;
+#  endif
 typedef          int       atomic_int;
 typedef unsigned int       atomic_uint;
 typedef          long      atomic_long;
@@ -98,6 +109,10 @@ typedef         ptrdiff_t atomic_ptrdiff_t;
 typedef          intmax_t atomic_intmax_t;
 typedef         uintmax_t atomic_uintmax_t;
 
+# if defined (__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4) || (defined (__clang__) && (defined (__x86_64__) || defined (__i386__)))
+
+/*** Intel/GCC atomics ***/
+
 #  define atomic_store(object,desired) \
     do { \
         *(object) = (desired); \
@@ -188,196 +203,103 @@ typedef         uintmax_t atomic_uintmax_t;
 #  define atomic_flag_clear_explicit(object,order) \
     atomic_flag_clear(object)
 
-# else
+# elif defined (__GNUC__)
 
 /*** No atomics ***/
 
-#  define ATOMIC_FLAG_INIT false
-
-#  define ATOMIC_VAR_INIT(value) (value)
-
-#  define atomic_init(obj, value) \
-    do { *(obj) = (value); } while(0)
-
-#  define kill_dependency(y) \
-    ((void)0)
-
-#  define atomic_thread_fence(order) \
-    __sync_synchronize()
-
-#  define atomic_signal_fence(order) \
-    ((void)0)
-
-#  define atomic_is_lock_free(obj) \
-    false
-
-typedef uintptr_t atomic_generic_t;
-typedef atomic_generic_t atomic_flag;
-typedef atomic_generic_t atomic_bool;
-//typedef atomic_generic_t atomic_char;
-//typedef atomic_generic_t atomic_schar;
-typedef atomic_generic_t atomic_uchar;
-//typedef atomic_generic_t atomic_short;
-typedef atomic_generic_t atomic_ushort;
-//typedef atomic_generic_t atomic_int;
-typedef atomic_generic_t atomic_uint;
-//typedef atomic_generic_t atomic_long;
-typedef atomic_generic_t atomic_ulong;
-//typedef atomic_generic_t atomic_llong;
-//typedef atomic_generic_t atomic_ullong;
-//typedef atomic_generic_t atomic_char16_t;
-//typedef atomic_generic_t atomic_char32_t;
-//typedef atomic_generic_t atomic_wchar_t;
-//typedef atomic_generic_t atomic_int_least8_t;
-typedef atomic_generic_t atomic_uint_least8_t;
-//typedef atomic_generic_t atomic_int_least16_t;
-typedef atomic_generic_t atomic_uint_least16_t;
-//typedef atomic_generic_t atomic_int_least32_t;
-typedef atomic_generic_t atomic_uint_least32_t;
-//typedef atomic_generic_t atomic_int_least64_t;
-//typedef atomic_generic_t atomic_uint_least64_t;
-//typedef atomic_generic_t atomic_int_fast8_t;
-typedef atomic_generic_t atomic_uint_fast8_t;
-//typedef atomic_generic_t atomic_int_fast16_t;
-typedef atomic_generic_t atomic_uint_fast16_t;
-//typedef atomic_generic_t atomic_int_fast32_t;
-typedef atomic_generic_t atomic_uint_fast32_t;
-//typedef atomic_generic_t atomic_int_fast64_t
-//typedef atomic_generic_t atomic_uint_fast64_t;
-//typedef atomic_generic_t atomic_intptr_t;
-typedef atomic_generic_t atomic_uintptr_t;
-typedef atomic_generic_t atomic_size_t;
-//typedef atomic_generic_t atomic_ptrdiff_t;
-//typedef atomic_generic_t atomic_intmax_t;
-//typedef atomic_generic_t atomic_uintmax_t;
-
-#define atomic_store(object,desired) \
+#  define atomic_store(object,desired) \
     do { \
+        typeof (object) _obj = (object); \
+        typeof (*object) _des = (desired); \
         vlc_global_lock(VLC_ATOMIC_MUTEX); \
-        *(object) = (desired); \
+        *_obj = _des; \
         vlc_global_unlock(VLC_ATOMIC_MUTEX); \
     } while (0)
-
 #  define atomic_store_explicit(object,desired,order) \
     atomic_store(object,desired)
 
-static inline uintptr_t atomic_load(atomic_generic_t *object)
-{
-    uintptr_t value;
-
-    vlc_global_lock(VLC_ATOMIC_MUTEX);
-    value = *object;
-    vlc_global_unlock(VLC_ATOMIC_MUTEX);
-    return value;
-}
+#  define atomic_load(object) \
+({ \
+    typeof (object) _obj = (object); \
+    typeof (*object) _old; \
+    vlc_global_lock(VLC_ATOMIC_MUTEX); \
+    _old = *_obj; \
+    vlc_global_unlock(VLC_ATOMIC_MUTEX); \
+    _old; \
+})
 #  define atomic_load_explicit(object,order) \
     atomic_load(object)
 
-static inline
-uintptr_t atomic_exchange(atomic_generic_t *object, uintptr_t desired)
-{
-    uintptr_t value;
-
-    vlc_global_lock(VLC_ATOMIC_MUTEX);
-    value = *object;
-    *object = desired;
-    vlc_global_unlock(VLC_ATOMIC_MUTEX);
-    return value;
-}
+#  define atomic_exchange(object,desired) \
+({ \
+    typeof (object) _obj = (object); \
+    typeof (*object) _des = (desired); \
+    typeof (*object) _old; \
+    vlc_global_lock(VLC_ATOMIC_MUTEX); \
+    _old = *_obj; \
+    *_obj = _des; \
+    vlc_global_unlock(VLC_ATOMIC_MUTEX); \
+    _old; \
+})
 #  define atomic_exchange_explicit(object,desired,order) \
     atomic_exchange(object,desired)
 
-static inline
-bool vlc_atomic_compare_exchange(atomic_generic_t *object,
-                                 uintptr_t *expected, uintptr_t desired)
-{
-    bool ret;
-
-    vlc_global_lock(VLC_ATOMIC_MUTEX);
-    ret = *object == *expected;
-    if (ret)
-        *object = desired;
-    else
-        *expected = *object;
-    vlc_global_unlock(VLC_ATOMIC_MUTEX);
-    return ret;
-}
 #  define atomic_compare_exchange_strong(object,expected,desired) \
-    vlc_atomic_compare_exchange(object, expected, desired)
+({ \
+    typeof (object) _obj = (object); \
+    typeof (object) _exp = (expected); \
+    typeof (*object) _des = (desired); \
+    bool ret; \
+    vlc_global_lock(VLC_ATOMIC_MUTEX); \
+    ret = *_obj == *_exp; \
+    if (ret) \
+        *_obj = _des; \
+    else \
+        *_exp = *_obj; \
+    vlc_global_unlock(VLC_ATOMIC_MUTEX); \
+    ret; \
+})
 #  define atomic_compare_exchange_strong_explicit(object,expected,desired,order) \
     atomic_compare_exchange_strong(object, expected, desired)
 #  define atomic_compare_exchange_weak(object,expected,desired) \
-    vlc_atomic_compare_exchange(object, expected, desired)
+    atomic_compare_exchange_strong(object, expected, desired)
 #  define atomic_compare_exchange_weak_explicit(object,expected,desired,order) \
     atomic_compare_exchange_weak(object, expected, desired)
 
-static inline
-uintmax_t atomic_fetch_add(atomic_generic_t *object, uintptr_t operand)
-{
-    uintptr_t value;
+#  define atomic_fetch_OP(object,desired,op) \
+({ \
+    typeof (object) _obj = (object); \
+    typeof (*object) _des = (desired); \
+    typeof (*object) _old; \
+    vlc_global_lock(VLC_ATOMIC_MUTEX); \
+    _old = *_obj; \
+    *_obj = (*_obj) op (_des); \
+    vlc_global_unlock(VLC_ATOMIC_MUTEX); \
+    _old; \
+})
 
-    vlc_global_lock(VLC_ATOMIC_MUTEX);
-    value = *object;
-    *object += operand;
-    vlc_global_unlock(VLC_ATOMIC_MUTEX);
-    return value;
-}
+#  define atomic_fetch_add(object,operand) \
+    atomic_fetch_OP(object,operand,+)
 #  define atomic_fetch_add_explicit(object,operand,order) \
     atomic_fetch_add(object,operand)
 
-static inline
-uintptr_t atomic_fetch_sub(atomic_generic_t *object, uintptr_t operand)
-{
-    uintptr_t value;
-
-    vlc_global_lock(VLC_ATOMIC_MUTEX);
-    value = *object;
-    *object -= operand;
-    vlc_global_unlock(VLC_ATOMIC_MUTEX);
-    return value;
-}
+#  define atomic_fetch_sub(object,operand) \
+    atomic_fetch_OP(object,operand,-)
 #  define atomic_fetch_sub_explicit(object,operand,order) \
     atomic_fetch_sub(object,operand)
 
-static inline
-uintptr_t atomic_fetch_or(atomic_generic_t *object, uintptr_t operand)
-{
-    uintptr_t value;
-
-    vlc_global_lock(VLC_ATOMIC_MUTEX);
-    value = *object;
-    *object |= operand;
-    vlc_global_unlock(VLC_ATOMIC_MUTEX);
-    return value;
-}
+#  define atomic_fetch_or(object,operand) \
+    atomic_fetch_OP(object,operand,|)
 #  define atomic_fetch_or_explicit(object,operand,order) \
     atomic_fetch_or(object,operand)
 
-static inline
-uintptr_t atomic_fetch_xor(atomic_generic_t *object, uintptr_t operand)
-{
-    uintptr_t value;
-
-    vlc_global_lock(VLC_ATOMIC_MUTEX);
-    value = *object;
-    *object ^= operand;
-    vlc_global_unlock(VLC_ATOMIC_MUTEX);
-    return value;
-}
+#  define atomic_fetch_xor(object,operand) \
+    atomic_fetch_OP(object,operand,^)
 #  define atomic_fetch_xor_explicit(object,operand,order) \
     atomic_fetch_sub(object,operand)
 
-static inline
-uintptr_t atomic_fetch_and(atomic_generic_t *object, uintptr_t operand)
-{
-    uintptr_t value;
-
-    vlc_global_lock(VLC_ATOMIC_MUTEX);
-    value = *object;
-    *object &= operand;
-    vlc_global_unlock(VLC_ATOMIC_MUTEX);
-    return value;
-}
+#  define atomic_fetch_and(object,operand) \
+    atomic_fetch_OP(object,operand,&)
 #  define atomic_fetch_and_explicit(object,operand,order) \
     atomic_fetch_and(object,operand)
 
@@ -393,78 +315,116 @@ uintptr_t atomic_fetch_and(atomic_generic_t *object, uintptr_t operand)
 #  define atomic_flag_clear_explicit(object,order) \
     atomic_flag_clear(object)
 
-# endif
+# elif defined (_MSC_VER)
 
-/**
- * Memory storage space for an atom. Never access it directly.
- */
-typedef union
-{
-    atomic_uintptr_t u;
-} vlc_atomic_t;
+# include <windows.h>
 
-/** Static initializer for \ref vlc_atomic_t */
-# define VLC_ATOMIC_INIT(val) { (val) }
+/*** Use the Interlocked API. ***/
 
-/* All functions return the atom value _after_ the operation. */
-static inline uintptr_t vlc_atomic_get(vlc_atomic_t *atom)
-{
-    return atomic_load(&atom->u);
-}
+/* Define macros in order to dispatch to the correct function depending on the type.
+   Several ranges are need because some operations are not implemented for all types. */
+#  define atomic_type_dispatch_32_64(operation, object, ...) \
+    (sizeof(*object) == 4 ? operation((LONG *)object, __VA_ARGS__) : \
+    sizeof(*object) == 8 ? operation##64((LONGLONG *)object, __VA_ARGS__) : \
+    (abort(), 0))
 
-static inline uintptr_t vlc_atomic_set(vlc_atomic_t *atom, uintptr_t v)
-{
-    atomic_store(&atom->u, v);
-    return v;
-}
+#  define atomic_type_dispatch_16_64(operation, object, ...) \
+    (sizeof(*object) == 2 ? operation##16((short *)object, __VA_ARGS__) : \
+    atomic_type_dispatch_32_64(operation, object, __VA_ARGS__))
 
-static inline uintptr_t vlc_atomic_add(vlc_atomic_t *atom, uintptr_t v)
-{
-    return atomic_fetch_add(&atom->u, v) + v;
-}
+#  define atomic_type_dispatch_8_64(operation, object, ...) \
+    (sizeof(*object) == 1 ? operation##8((char *)object, __VA_ARGS__) : \
+    atomic_type_dispatch_16_64(operation, object, __VA_ARGS__))
 
-static inline uintptr_t vlc_atomic_sub (vlc_atomic_t *atom, uintptr_t v)
-{
-    return atomic_fetch_sub (&atom->u, v) - v;
-}
+#  define atomic_store(object,desired) \
+    atomic_type_dispatch_16_64(InterlockedExchange, object, desired)
+#  define atomic_store_explicit(object,desired,order) \
+    atomic_store(object, desired)
 
-static inline uintptr_t vlc_atomic_inc (vlc_atomic_t *atom)
-{
-    return vlc_atomic_add (atom, 1);
-}
+#  define atomic_load(object) \
+    atomic_type_dispatch_16_64(InterlockedCompareExchange, object, 0, 0)
+#  define atomic_load_explicit(object,order) \
+    atomic_load(object)
 
-static inline uintptr_t vlc_atomic_dec (vlc_atomic_t *atom)
-{
-    return vlc_atomic_sub (atom, 1);
-}
+#  define atomic_exchange(object,desired) \
+    atomic_type_dispatch_16_64(InterlockedExchange, object, desired)
+#  define atomic_exchange_explicit(object,desired,order) \
+    atomic_exchange(object, desired)
 
-static inline uintptr_t vlc_atomic_swap(vlc_atomic_t *atom, uintptr_t v)
-{
-    return atomic_exchange(&atom->u, v);
-}
+#  define atomic_compare_exchange_strong(object,expected,desired) \
+    atomic_type_dispatch_16_64(InterlockedCompareExchange, object, *expected, desired) == *expected
+#  define atomic_compare_exchange_strong_explicit(object,expected,desired,order) \
+    atomic_compare_exchange_strong(object, expected, desired)
+#  define atomic_compare_exchange_weak(object,expected,desired) \
+    atomic_compare_exchange_strong(object, expected, desired)
+#  define atomic_compare_exchange_weak_explicit(object,expected,desired,order) \
+    atomic_compare_exchange_weak(object, expected, desired)
+
+#  define atomic_fetch_add(object,operand) \
+    atomic_type_dispatch_32_64(InterlockedExchangeAdd, object, operand)
+#  define atomic_fetch_add_explicit(object,operand,order) \
+    atomic_fetch_add(object, operand)
+
+#  define atomic_fetch_sub(object,operand) \
+    atomic_type_dispatch_32_64(InterlockedExchangeAdd, object, -(LONGLONG)operand)
+#  define atomic_fetch_sub_explicit(object,operand,order) \
+    atomic_fetch_sub(object, operand)
+
+#  define atomic_fetch_or(object,operand) \
+    atomic_type_dispatch_8_64(InterlockedOr, object, operand)
+#  define atomic_fetch_or_explicit(object,operand,order) \
+    atomic_fetch_or(object, operand)
+
+#  define atomic_fetch_xor(object,operand) \
+    atomic_type_dispatch_8_64(InterlockedXor, object, operand)
+#  define atomic_fetch_xor_explicit(object,operand,order) \
+    atomic_fetch_sub(object, operand)
+
+#  define atomic_fetch_and(object,operand) \
+    atomic_type_dispatch_8_64(InterlockedAnd, object, operand)
+#  define atomic_fetch_and_explicit(object,operand,order) \
+    atomic_fetch_and(object, operand)
+
+#  define atomic_flag_test_and_set(object) \
+    atomic_exchange(object, true)
+
+#  define atomic_flag_test_and_set_explicit(object,order) \
+    atomic_flag_test_and_set(object)
 
-static inline uintptr_t vlc_atomic_compare_swap(vlc_atomic_t *atom,
-                                                uintptr_t u, uintptr_t v)
+#  define atomic_flag_clear(object) \
+    atomic_store(object, false)
+
+#  define atomic_flag_clear_explicit(object,order) \
+    atomic_flag_clear(object)
+
+# else
+#  error FIXME: implement atomic operations for this compiler.
+# endif
+# endif
+
+typedef atomic_uint_least32_t vlc_atomic_float;
+
+static inline void vlc_atomic_init_float(vlc_atomic_float *var, float f)
 {
-    atomic_compare_exchange_strong(&atom->u, &u, v);
-    return u;
+    union { float f; uint32_t i; } u;
+    u.f = f;
+    atomic_init(var, u.i);
 }
 
 /** Helper to retrieve a single precision from an atom. */
-static inline float vlc_atomic_getf(vlc_atomic_t *atom)
+static inline float vlc_atomic_load_float(vlc_atomic_float *atom)
 {
-    union { float f; uintptr_t i; } u;
-    u.i = vlc_atomic_get(atom);
+    union { float f; uint32_t i; } u;
+    u.i = atomic_load(atom);
     return u.f;
 }
 
 /** Helper to store a single precision into an atom. */
-static inline float vlc_atomic_setf(vlc_atomic_t *atom, float f)
+static inline void vlc_atomic_store_float(vlc_atomic_float *atom, float f)
 {
-    union { float f; uintptr_t i; } u;
+    union { float f; uint32_t i; } u;
     u.f = f;
-    vlc_atomic_set(atom, u.i);
-    return f;
+    atomic_store(atom, u.i);
 }
 
 #endif