Halide 22.0.0 Halide compiler and libraries

runtime_atomics.h
Go to the documentation of this file.
1#ifndef HALIDE_RUNTIME_RUNTIME_ATOMICS_H
2#define HALIDE_RUNTIME_RUNTIME_ATOMICS_H
3
4// This file provides an abstraction layer over the __sync/__atomic builtins
5// in Clang; for various reasons, we use __sync for 32-bit targets, and
6// __atomic for 64-bit. At some point it may be desirable/necessary to
7// migrate 32-bit to __atomic as well, at which time this file can
8// likely go away. See https://github.com/halide/Halide/issues/7431 for
9// a discussion of the history and issues as to why we work this way.
10
11#include "HalideRuntime.h"
12
13 namespace Halide {
14 namespace Runtime {
15 namespace Internal {
16 namespace Synchronization {
17
18 namespace {
19
20// TODO: most of these wrappers should do the remove_volatile for secondary arguments;
21// I've only put it in place for the locations necessary at this time.
22 template<class T>
23 struct remove_volatile {
24 typedef T type;
25};
26 template<class T>
27 struct remove_volatile<volatile T> {
28 typedef T type;
29};
30
31#ifdef BITS_32
32 ALWAYS_INLINE uintptr_t atomic_and_fetch_release(uintptr_t *addr, uintptr_t val) {
33 return __sync_and_and_fetch(addr, val);
34}
35
36 template<typename T>
37 ALWAYS_INLINE T atomic_fetch_add_acquire_release(T *addr, T val) {
38 return __sync_fetch_and_add(addr, val);
39}
40
41template<typename T, typename TV = typename remove_volatile<T>::type>
42 ALWAYS_INLINE TV atomic_fetch_add_sequentially_consistent(T *addr, TV val) {
43 return __sync_fetch_and_add(addr, val);
44}
45
46template<typename T, typename TV = typename remove_volatile<T>::type>
47 ALWAYS_INLINE TV atomic_fetch_sub_sequentially_consistent(T *addr, TV val) {
48 return __sync_fetch_and_sub(addr, val);
49}
50
51template<typename T, typename TV = typename remove_volatile<T>::type>
52 ALWAYS_INLINE TV atomic_fetch_or_sequentially_consistent(T *addr, TV val) {
53 return __sync_fetch_and_or(addr, val);
54}
55
56template<typename T, typename TV = typename remove_volatile<T>::type>
57 ALWAYS_INLINE TV atomic_add_fetch_sequentially_consistent(T *addr, TV val) {
58 return __sync_add_and_fetch(addr, val);
59}
60
61template<typename T, typename TV = typename remove_volatile<T>::type>
62 ALWAYS_INLINE TV atomic_sub_fetch_sequentially_consistent(T *addr, TV val) {
63 return __sync_sub_and_fetch(addr, val);
64}
65
66template<typename T, typename TV = typename remove_volatile<T>::type>
67 ALWAYS_INLINE bool cas_strong_sequentially_consistent_helper(T *addr, TV *expected, TV *desired) {
68 TV oldval = *expected;
69 TV gotval = __sync_val_compare_and_swap(addr, oldval, *desired);
70 *expected = gotval;
71 return oldval == gotval;
72}
73
74 ALWAYS_INLINE bool atomic_cas_strong_release_relaxed(uintptr_t *addr, uintptr_t *expected, uintptr_t *desired) {
75 return cas_strong_sequentially_consistent_helper(addr, expected, desired);
76}
77
78template<typename T, typename TV = typename remove_volatile<T>::type>
79 ALWAYS_INLINE bool atomic_cas_strong_sequentially_consistent(T *addr, TV *expected, TV *desired) {
80 return cas_strong_sequentially_consistent_helper(addr, expected, desired);
81}
82
83 ALWAYS_INLINE bool atomic_cas_weak_release_relaxed(uintptr_t *addr, uintptr_t *expected, uintptr_t *desired) {
84 return cas_strong_sequentially_consistent_helper(addr, expected, desired);
85}
86
87 template<typename T>
88 ALWAYS_INLINE bool atomic_cas_weak_relacq_relaxed(T *addr, T *expected, T *desired) {
89 return cas_strong_sequentially_consistent_helper(addr, expected, desired);
90}
91
92 ALWAYS_INLINE bool atomic_cas_weak_relaxed_relaxed(uintptr_t *addr, uintptr_t *expected, uintptr_t *desired) {
93 return cas_strong_sequentially_consistent_helper(addr, expected, desired);
94}
95
96 ALWAYS_INLINE bool atomic_cas_weak_acquire_relaxed(uintptr_t *addr, uintptr_t *expected, uintptr_t *desired) {
97 return cas_strong_sequentially_consistent_helper(addr, expected, desired);
98}
99
100 template<typename T>
101 ALWAYS_INLINE T atomic_fetch_and_release(T *addr, T val) {
102 return __sync_fetch_and_and(addr, val);
103}
104
105template<typename T, typename TV = typename remove_volatile<T>::type>
106 ALWAYS_INLINE TV atomic_fetch_and_sequentially_consistent(T *addr, TV val) {
107 return __sync_fetch_and_and(addr, val);
108}
109
110 template<typename T>
111 ALWAYS_INLINE void atomic_load_relaxed(T *addr, T *val) {
112 *val = *addr;
113}
114
115 template<typename T>
116 ALWAYS_INLINE void atomic_load_acquire(T *addr, T *val) {
117 __sync_synchronize();
118 *val = *addr;
119}
120
121 template<typename T>
122 ALWAYS_INLINE T atomic_exchange_acquire(T *addr, T val) {
123 // Despite the name, this is really just an exchange operation with acquire ordering.
124 return __sync_lock_test_and_set(addr, val);
125}
126
127 ALWAYS_INLINE uintptr_t atomic_or_fetch_relaxed(uintptr_t *addr, uintptr_t val) {
128 return __sync_or_and_fetch(addr, val);
129}
130
131 template<typename T>
132 ALWAYS_INLINE void atomic_store_relaxed(T *addr, T *val) {
133 *addr = *val;
134}
135
136 template<typename T>
137 ALWAYS_INLINE void atomic_store_release(T *addr, T *val) {
138 *addr = *val;
139 __sync_synchronize();
140}
141
142template<typename T, typename TV = typename remove_volatile<T>::type>
143 ALWAYS_INLINE void atomic_store_sequentially_consistent(T *addr, TV *val) {
144 *addr = *val;
145 __sync_synchronize();
146}
147
148 ALWAYS_INLINE void atomic_thread_fence_acquire() {
149 __sync_synchronize();
150}
151
152 ALWAYS_INLINE void atomic_thread_fence_sequentially_consistent() {
153 __sync_synchronize();
154}
155
156#else
157
158 ALWAYS_INLINE uintptr_t atomic_and_fetch_release(uintptr_t *addr, uintptr_t val) {
159 return __atomic_and_fetch(addr, val, __ATOMIC_RELEASE);
160}
161
162 template<typename T>
163 ALWAYS_INLINE T atomic_fetch_add_acquire_release(T *addr, T val) {
164 return __atomic_fetch_add(addr, val, __ATOMIC_ACQ_REL);
165}
166
167template<typename T, typename TV = typename remove_volatile<T>::type>
168 ALWAYS_INLINE TV atomic_fetch_add_sequentially_consistent(T *addr, TV val) {
169 return __atomic_fetch_add(addr, val, __ATOMIC_SEQ_CST);
170}
171
172template<typename T, typename TV = typename remove_volatile<T>::type>
173 ALWAYS_INLINE TV atomic_fetch_sub_sequentially_consistent(T *addr, TV val) {
174 return __atomic_fetch_sub(addr, val, __ATOMIC_SEQ_CST);
175}
176
177template<typename T, typename TV = typename remove_volatile<T>::type>
178 ALWAYS_INLINE TV atomic_fetch_or_sequentially_consistent(T *addr, TV val) {
179 return __atomic_fetch_or(addr, val, __ATOMIC_SEQ_CST);
180}
181
182template<typename T, typename TV = typename remove_volatile<T>::type>
183 ALWAYS_INLINE TV atomic_add_fetch_sequentially_consistent(T *addr, TV val) {
184 return __atomic_add_fetch(addr, val, __ATOMIC_SEQ_CST);
185}
186
187template<typename T, typename TV = typename remove_volatile<T>::type>
188 ALWAYS_INLINE TV atomic_sub_fetch_sequentially_consistent(T *addr, TV val) {
189 return __atomic_sub_fetch(addr, val, __ATOMIC_SEQ_CST);
190}
191
192 ALWAYS_INLINE bool atomic_cas_strong_release_relaxed(uintptr_t *addr, uintptr_t *expected, uintptr_t *desired) {
193 return __atomic_compare_exchange(addr, expected, desired, false, __ATOMIC_RELEASE, __ATOMIC_RELAXED);
194}
195
196template<typename T, typename TV = typename remove_volatile<T>::type>
197 ALWAYS_INLINE bool atomic_cas_strong_sequentially_consistent(T *addr, TV *expected, TV *desired) {
198 return __atomic_compare_exchange(addr, expected, desired, false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST);
199}
200
201 template<typename T>
202 ALWAYS_INLINE bool atomic_cas_weak_relacq_relaxed(T *addr, T *expected, T *desired) {
203 return __atomic_compare_exchange(addr, expected, desired, true, __ATOMIC_ACQ_REL, __ATOMIC_RELAXED);
204}
205
206 ALWAYS_INLINE bool atomic_cas_weak_release_relaxed(uintptr_t *addr, uintptr_t *expected, uintptr_t *desired) {
207 return __atomic_compare_exchange(addr, expected, desired, true, __ATOMIC_RELEASE, __ATOMIC_RELAXED);
208}
209
210 ALWAYS_INLINE bool atomic_cas_weak_relaxed_relaxed(uintptr_t *addr, uintptr_t *expected, uintptr_t *desired) {
211 return __atomic_compare_exchange(addr, expected, desired, true, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
212}
213
214 ALWAYS_INLINE bool atomic_cas_weak_acquire_relaxed(uintptr_t *addr, uintptr_t *expected, uintptr_t *desired) {
215 return __atomic_compare_exchange(addr, expected, desired, true, __ATOMIC_ACQUIRE, __ATOMIC_RELAXED);
216}
217
218 template<typename T>
219 ALWAYS_INLINE uintptr_t atomic_fetch_and_release(T *addr, T val) {
220 return __atomic_fetch_and(addr, val, __ATOMIC_RELEASE);
221}
222
223template<typename T, typename TV = typename remove_volatile<T>::type>
224 ALWAYS_INLINE uintptr_t atomic_fetch_and_sequentially_consistent(T *addr, TV val) {
225 return __atomic_fetch_and(addr, val, __ATOMIC_SEQ_CST);
226}
227
228 template<typename T>
229 ALWAYS_INLINE void atomic_load_relaxed(T *addr, T *val) {
230 __atomic_load(addr, val, __ATOMIC_RELAXED);
231}
232
233 template<typename T>
234 ALWAYS_INLINE void atomic_load_acquire(T *addr, T *val) {
235 __atomic_load(addr, val, __ATOMIC_ACQUIRE);
236 __sync_synchronize();
237 *val = *addr;
238}
239
240 template<typename T>
241 ALWAYS_INLINE T atomic_exchange_acquire(T *addr, T val) {
242 T result;
243 __atomic_exchange(addr, &val, &result, __ATOMIC_ACQUIRE);
244 return result;
245}
246
247 ALWAYS_INLINE uintptr_t atomic_or_fetch_relaxed(uintptr_t *addr, uintptr_t val) {
248 return __atomic_or_fetch(addr, val, __ATOMIC_RELAXED);
249}
250
251 template<typename T>
252 ALWAYS_INLINE void atomic_store_relaxed(T *addr, T *val) {
253 __atomic_store(addr, val, __ATOMIC_RELAXED);
254}
255
256 template<typename T>
257 ALWAYS_INLINE void atomic_store_release(T *addr, T *val) {
258 __atomic_store(addr, val, __ATOMIC_RELEASE);
259}
260
261template<typename T, typename TV = typename remove_volatile<T>::type>
262 ALWAYS_INLINE void atomic_store_sequentially_consistent(T *addr, TV *val) {
263 __atomic_store(addr, val, __ATOMIC_SEQ_CST);
264}
265
266 ALWAYS_INLINE void atomic_thread_fence_acquire() {
267 __atomic_thread_fence(__ATOMIC_ACQUIRE);
268}
269
270 ALWAYS_INLINE void atomic_thread_fence_sequentially_consistent() {
271 __atomic_thread_fence(__ATOMIC_SEQ_CST);
272}
273
274#endif
275
276} // namespace
277
278} // namespace Synchronization
279} // namespace Internal
280} // namespace Runtime
281} // namespace Halide
282
283#endif // HALIDE_RUNTIME_RUNTIME_ATOMICS_H
HalideRuntime.h
This file declares the routines used by Halide internally in its runtime.
Halide
This file defines the class FunctionDAG, which is our representation of a Halide pipeline,...
Definition: AbstractGenerator.h:19
Halide::LinkageType::Internal
@ Internal
Not visible externally, similar to 'static' linkage in C.
uintptr_t
__UINTPTR_TYPE__ uintptr_t
Definition: runtime_internal.h:75
ALWAYS_INLINE
#define ALWAYS_INLINE
Definition: runtime_internal.h:57