|
111
|
1 //===-- sanitizer_atomic_clang_other.h --------------------------*- C++ -*-===//
|
|
|
2 //
|
|
145
|
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
|
4 // See https://llvm.org/LICENSE.txt for license information.
|
|
|
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
111
|
6 //
|
|
|
7 //===----------------------------------------------------------------------===//
|
|
|
8 //
|
|
|
9 // This file is a part of ThreadSanitizer/AddressSanitizer runtime.
|
|
|
10 // Not intended for direct inclusion. Include sanitizer_atomic.h.
|
|
|
11 //
|
|
|
12 //===----------------------------------------------------------------------===//
|
|
|
13
|
|
|
14 #ifndef SANITIZER_ATOMIC_CLANG_OTHER_H
|
|
|
15 #define SANITIZER_ATOMIC_CLANG_OTHER_H
|
|
|
16
|
|
|
17 namespace __sanitizer {
|
|
|
18
|
|
|
19
|
|
|
20 INLINE void proc_yield(int cnt) {
|
|
|
21 __asm__ __volatile__("" ::: "memory");
|
|
|
22 }
|
|
|
23
|
|
|
24 template<typename T>
|
|
|
25 INLINE typename T::Type atomic_load(
|
|
|
26 const volatile T *a, memory_order mo) {
|
|
|
27 DCHECK(mo & (memory_order_relaxed | memory_order_consume
|
|
|
28 | memory_order_acquire | memory_order_seq_cst));
|
|
|
29 DCHECK(!((uptr)a % sizeof(*a)));
|
|
|
30 typename T::Type v;
|
|
|
31
|
|
|
32 if (sizeof(*a) < 8 || sizeof(void*) == 8) {
|
|
|
33 // Assume that aligned loads are atomic.
|
|
|
34 if (mo == memory_order_relaxed) {
|
|
|
35 v = a->val_dont_use;
|
|
|
36 } else if (mo == memory_order_consume) {
|
|
|
37 // Assume that processor respects data dependencies
|
|
|
38 // (and that compiler won't break them).
|
|
|
39 __asm__ __volatile__("" ::: "memory");
|
|
|
40 v = a->val_dont_use;
|
|
|
41 __asm__ __volatile__("" ::: "memory");
|
|
|
42 } else if (mo == memory_order_acquire) {
|
|
|
43 __asm__ __volatile__("" ::: "memory");
|
|
|
44 v = a->val_dont_use;
|
|
|
45 __sync_synchronize();
|
|
|
46 } else { // seq_cst
|
|
|
47 // E.g. on POWER we need a hw fence even before the store.
|
|
|
48 __sync_synchronize();
|
|
|
49 v = a->val_dont_use;
|
|
|
50 __sync_synchronize();
|
|
|
51 }
|
|
|
52 } else {
|
|
|
53 // 64-bit load on 32-bit platform.
|
|
|
54 // Gross, but simple and reliable.
|
|
|
55 // Assume that it is not in read-only memory.
|
|
|
56 v = __sync_fetch_and_add(
|
|
|
57 const_cast<typename T::Type volatile *>(&a->val_dont_use), 0);
|
|
|
58 }
|
|
|
59 return v;
|
|
|
60 }
|
|
|
61
|
|
|
62 template<typename T>
|
|
|
63 INLINE void atomic_store(volatile T *a, typename T::Type v, memory_order mo) {
|
|
|
64 DCHECK(mo & (memory_order_relaxed | memory_order_release
|
|
|
65 | memory_order_seq_cst));
|
|
|
66 DCHECK(!((uptr)a % sizeof(*a)));
|
|
|
67
|
|
|
68 if (sizeof(*a) < 8 || sizeof(void*) == 8) {
|
|
|
69 // Assume that aligned loads are atomic.
|
|
|
70 if (mo == memory_order_relaxed) {
|
|
|
71 a->val_dont_use = v;
|
|
|
72 } else if (mo == memory_order_release) {
|
|
|
73 __sync_synchronize();
|
|
|
74 a->val_dont_use = v;
|
|
|
75 __asm__ __volatile__("" ::: "memory");
|
|
|
76 } else { // seq_cst
|
|
|
77 __sync_synchronize();
|
|
|
78 a->val_dont_use = v;
|
|
|
79 __sync_synchronize();
|
|
|
80 }
|
|
|
81 } else {
|
|
|
82 // 64-bit store on 32-bit platform.
|
|
|
83 // Gross, but simple and reliable.
|
|
|
84 typename T::Type cmp = a->val_dont_use;
|
|
|
85 typename T::Type cur;
|
|
|
86 for (;;) {
|
|
|
87 cur = __sync_val_compare_and_swap(&a->val_dont_use, cmp, v);
|
|
145
|
88 if (cur == cmp || cur == v)
|
|
111
|
89 break;
|
|
|
90 cmp = cur;
|
|
|
91 }
|
|
|
92 }
|
|
|
93 }
|
|
|
94
|
|
|
95 } // namespace __sanitizer
|
|
|
96
|
|
|
97 #endif // #ifndef SANITIZER_ATOMIC_CLANG_OTHER_H
|
