aboutsummaryrefslogtreecommitdiff
path: root/sysdeps/mips/atomic-machine.h
blob: 88805ee30b11d8af96e296b8794a8a0d2cedfeb7 (plain)
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
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/* Low-level functions for atomic operations. Mips version.
   Copyright (C) 2005-2022 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/>.  */

#ifndef _MIPS_ATOMIC_MACHINE_H
#define _MIPS_ATOMIC_MACHINE_H 1

#include <sgidefs.h>

#if _MIPS_SIM == _ABIO32 && __mips < 2
#define MIPS_PUSH_MIPS2 ".set	mips2\n\t"
#else
#define MIPS_PUSH_MIPS2
#endif

#if _MIPS_SIM == _ABIO32 || _MIPS_SIM == _ABIN32
#define __HAVE_64B_ATOMICS 0
#else
#define __HAVE_64B_ATOMICS 1
#endif

/* See the comments in <sys/asm.h> about the use of the sync instruction.  */
#ifndef MIPS_SYNC
# define MIPS_SYNC	sync
#endif

#define MIPS_SYNC_STR_2(X) #X
#define MIPS_SYNC_STR_1(X) MIPS_SYNC_STR_2(X)
#define MIPS_SYNC_STR MIPS_SYNC_STR_1(MIPS_SYNC)

#define USE_ATOMIC_COMPILER_BUILTINS 1

/* MIPS is an LL/SC machine.  However, XLP has a direct atomic exchange
   instruction which will be used by __atomic_exchange_n.  */
#ifdef _MIPS_ARCH_XLP
# define ATOMIC_EXCHANGE_USES_CAS 0
#else
# define ATOMIC_EXCHANGE_USES_CAS 1
#endif

/* 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) \
  (abort (), 0)

#define __arch_compare_and_exchange_bool_16_int(mem, newval, oldval, model) \
  (abort (), 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_val_8_int(mem, newval, oldval, model) \
  (abort (), (typeof(*mem)) 0)

#define __arch_compare_and_exchange_val_16_int(mem, newval, oldval, model) \
  (abort (), (typeof(*mem)) 0)

#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;								\
  })

#if _MIPS_SIM == _ABIO32
  /* We can't do an atomic 64-bit operation in O32.  */
# define __arch_compare_and_exchange_bool_64_int(mem, newval, oldval, model) \
  (abort (), 0)
# define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
  (abort (), (typeof(*mem)) 0)
#else
# define __arch_compare_and_exchange_bool_64_int(mem, newval, oldval, model) \
  __arch_compare_and_exchange_bool_32_int (mem, newval, oldval, model)
# define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
  __arch_compare_and_exchange_val_32_int (mem, newval, oldval, model)
#endif

/* 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)


/* Atomic exchange (without compare).  */

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

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

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

#if _MIPS_SIM == _ABIO32
/* We can't do an atomic 64-bit operation in O32.  */
# define __arch_exchange_64_int(mem, newval, model)	\
  (abort (), (typeof(*mem)) 0)
#else
# define __arch_exchange_64_int(mem, newval, model)	\
  __atomic_exchange_n (mem, newval, model)
#endif

#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)


/* Atomically add value and return the previous (unincremented) value.  */

#define __arch_exchange_and_add_8_int(mem, value, model)	\
  (abort (), (typeof(*mem)) 0)

#define __arch_exchange_and_add_16_int(mem, value, model)	\
  (abort (), (typeof(*mem)) 0)

#define __arch_exchange_and_add_32_int(mem, value, model)	\
  __atomic_fetch_add (mem, value, model)

#if _MIPS_SIM == _ABIO32
/* We can't do an atomic 64-bit operation in O32.  */
# define __arch_exchange_and_add_64_int(mem, value, model)	\
  (abort (), (typeof(*mem)) 0)
#else
# define __arch_exchange_and_add_64_int(mem, value, model)	\
  __atomic_fetch_add (mem, value, model)
#endif

#define atomic_exchange_and_add_acq(mem, value)			\
  __atomic_val_bysize (__arch_exchange_and_add, int, mem, value,	\
		       __ATOMIC_ACQUIRE)

#define atomic_exchange_and_add_rel(mem, value)			\
  __atomic_val_bysize (__arch_exchange_and_add, int, mem, value,	\
		       __ATOMIC_RELEASE)

/* TODO: More atomic operations could be implemented efficiently; only the
   basic requirements are done.  */

#ifdef __mips16
# define atomic_full_barrier() __sync_synchronize ()

#else /* !__mips16 */
# define atomic_full_barrier() \
  __asm__ __volatile__ (".set push\n\t"					      \
			MIPS_PUSH_MIPS2					      \
			MIPS_SYNC_STR "\n\t"				      \
			".set pop" : : : "memory")
#endif /* !__mips16 */

#endif /* atomic-machine.h */