about summary refs log tree commit diff
path: root/sysdeps/arm/atomic-machine.h
blob: 7928ff29d8d1ac1e6483b8dab476be9409f3f6b3 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
/* Atomic operations.  Pure ARM version.
   Copyright (C) 2002-2021 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library.  If not, see
   <https://www.gnu.org/licenses/>.  */

#include <stdint.h>

typedef int8_t atomic8_t;
typedef uint8_t uatomic8_t;
typedef int_fast8_t atomic_fast8_t;
typedef uint_fast8_t uatomic_fast8_t;

typedef int32_t atomic32_t;
typedef uint32_t uatomic32_t;
typedef int_fast32_t atomic_fast32_t;
typedef uint_fast32_t uatomic_fast32_t;

typedef intptr_t atomicptr_t;
typedef uintptr_t uatomicptr_t;
typedef intmax_t atomic_max_t;
typedef uintmax_t uatomic_max_t;

#define __HAVE_64B_ATOMICS 0
#define USE_ATOMIC_COMPILER_BUILTINS 0
#define ATOMIC_EXCHANGE_USES_CAS 1

void __arm_link_error (void);

#ifdef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4
# define atomic_full_barrier() __sync_synchronize ()
#else
# define atomic_full_barrier() __arm_assisted_full_barrier ()
#endif

/* An OS-specific atomic-machine.h file will define this macro if
   the OS can provide something.  If not, we'll fail to build
   with a compiler that doesn't supply the operation.  */
#ifndef __arm_assisted_full_barrier
# define __arm_assisted_full_barrier()  __arm_link_error()
#endif

/* Use the atomic builtins provided by GCC in case the backend provides
   a pattern to do this efficiently.  */
#ifdef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4

# define atomic_exchange_acq(mem, value)                                \
  __atomic_val_bysize (__arch_exchange, int, mem, value, __ATOMIC_ACQUIRE)

# define atomic_exchange_rel(mem, value)                                \
  __atomic_val_bysize (__arch_exchange, int, mem, value, __ATOMIC_RELEASE)

/* Atomic exchange (without compare).  */

# define __arch_exchange_8_int(mem, newval, model)      \
  (__arm_link_error (), (typeof (*mem)) 0)

# define __arch_exchange_16_int(mem, newval, model)     \
  (__arm_link_error (), (typeof (*mem)) 0)

# define __arch_exchange_32_int(mem, newval, model)     \
  __atomic_exchange_n (mem, newval, model)

# define __arch_exchange_64_int(mem, newval, model)     \
  (__arm_link_error (), (typeof (*mem)) 0)

/* Compare and exchange with "acquire" semantics, ie barrier after.  */

# define atomic_compare_and_exchange_bool_acq(mem, new, old)    \
  __atomic_bool_bysize (__arch_compare_and_exchange_bool, int,  \
                        mem, new, old, __ATOMIC_ACQUIRE)

# define atomic_compare_and_exchange_val_acq(mem, new, old)     \
  __atomic_val_bysize (__arch_compare_and_exchange_val, int,    \
                       mem, new, old, __ATOMIC_ACQUIRE)

/* Compare and exchange with "release" semantics, ie barrier before.  */

# define atomic_compare_and_exchange_val_rel(mem, new, old)      \
  __atomic_val_bysize (__arch_compare_and_exchange_val, int,    \
                       mem, new, old, __ATOMIC_RELEASE)

/* Compare and exchange.
   For all "bool" routines, we return FALSE if exchange succesful.  */

# define __arch_compare_and_exchange_bool_8_int(mem, newval, oldval, model) \
  ({__arm_link_error (); 0; })

# define __arch_compare_and_exchange_bool_16_int(mem, newval, oldval, model) \
  ({__arm_link_error (); 0; })

# define __arch_compare_and_exchange_bool_32_int(mem, newval, oldval, model) \
  ({                                                                    \
    typeof (*mem) __oldval = (oldval);                                  \
    !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0,   \
                                  model, __ATOMIC_RELAXED);             \
  })

# define __arch_compare_and_exchange_bool_64_int(mem, newval, oldval, model) \
  ({__arm_link_error (); 0; })

# define __arch_compare_and_exchange_val_8_int(mem, newval, oldval, model) \
  ({__arm_link_error (); oldval; })

# define __arch_compare_and_exchange_val_16_int(mem, newval, oldval, model) \
  ({__arm_link_error (); oldval; })

# define __arch_compare_and_exchange_val_32_int(mem, newval, oldval, model) \
  ({                                                                    \
    typeof (*mem) __oldval = (oldval);                                  \
    __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0,    \
                                 model, __ATOMIC_RELAXED);              \
    __oldval;                                                           \
  })

# define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
  ({__arm_link_error (); oldval; })

#else
# define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \
  __arm_assisted_compare_and_exchange_val_32_acq ((mem), (newval), (oldval))
#endif

#ifndef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4
/* We don't support atomic operations on any non-word types.
   So make them link errors.  */
# define __arch_compare_and_exchange_val_8_acq(mem, newval, oldval) \
  ({ __arm_link_error (); oldval; })

# define __arch_compare_and_exchange_val_16_acq(mem, newval, oldval) \
  ({ __arm_link_error (); oldval; })

# define __arch_compare_and_exchange_val_64_acq(mem, newval, oldval) \
  ({ __arm_link_error (); oldval; })
#endif

/* An OS-specific atomic-machine.h file will define this macro if
   the OS can provide something.  If not, we'll fail to build
   with a compiler that doesn't supply the operation.  */
#ifndef __arm_assisted_compare_and_exchange_val_32_acq
# define __arm_assisted_compare_and_exchange_val_32_acq(mem, newval, oldval) \
  ({ __arm_link_error (); oldval; })
#endif