]>
Commit | Line | Data |
---|---|---|
f35db108 WM |
1 | //===-- sanitizer_atomic_clang.h --------------------------------*- C++ -*-===// |
2 | // | |
b667dd70 ML |
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 | |
f35db108 WM |
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_H | |
15 | #define SANITIZER_ATOMIC_CLANG_H | |
16 | ||
dee5ea7a KS |
17 | #if defined(__i386__) || defined(__x86_64__) |
18 | # include "sanitizer_atomic_clang_x86.h" | |
19 | #else | |
20 | # include "sanitizer_atomic_clang_other.h" | |
21 | #endif | |
22 | ||
f35db108 WM |
23 | namespace __sanitizer { |
24 | ||
dee5ea7a KS |
25 | // We would like to just use compiler builtin atomic operations |
26 | // for loads and stores, but they are mostly broken in clang: | |
27 | // - they lead to vastly inefficient code generation | |
28 | // (http://llvm.org/bugs/show_bug.cgi?id=17281) | |
29 | // - 64-bit atomic operations are not implemented on x86_32 | |
30 | // (http://llvm.org/bugs/show_bug.cgi?id=15034) | |
31 | // - they are not implemented on ARM | |
32 | // error: undefined reference to '__atomic_load_4' | |
33 | ||
34 | // See http://www.cl.cam.ac.uk/~pes20/cpp/cpp0xmappings.html | |
35 | // for mappings of the memory model to different processors. | |
36 | ||
f35db108 WM |
37 | INLINE void atomic_signal_fence(memory_order) { |
38 | __asm__ __volatile__("" ::: "memory"); | |
39 | } | |
40 | ||
41 | INLINE void atomic_thread_fence(memory_order) { | |
42 | __sync_synchronize(); | |
43 | } | |
44 | ||
f35db108 WM |
45 | template<typename T> |
46 | INLINE typename T::Type atomic_fetch_add(volatile T *a, | |
47 | typename T::Type v, memory_order mo) { | |
48 | (void)mo; | |
49 | DCHECK(!((uptr)a % sizeof(*a))); | |
50 | return __sync_fetch_and_add(&a->val_dont_use, v); | |
51 | } | |
52 | ||
53 | template<typename T> | |
54 | INLINE typename T::Type atomic_fetch_sub(volatile T *a, | |
55 | typename T::Type v, memory_order mo) { | |
56 | (void)mo; | |
57 | DCHECK(!((uptr)a % sizeof(*a))); | |
58 | return __sync_fetch_and_add(&a->val_dont_use, -v); | |
59 | } | |
60 | ||
61 | template<typename T> | |
62 | INLINE typename T::Type atomic_exchange(volatile T *a, | |
63 | typename T::Type v, memory_order mo) { | |
64 | DCHECK(!((uptr)a % sizeof(*a))); | |
65 | if (mo & (memory_order_release | memory_order_acq_rel | memory_order_seq_cst)) | |
66 | __sync_synchronize(); | |
67 | v = __sync_lock_test_and_set(&a->val_dont_use, v); | |
68 | if (mo == memory_order_seq_cst) | |
69 | __sync_synchronize(); | |
70 | return v; | |
71 | } | |
72 | ||
5d3805fc JJ |
73 | template <typename T> |
74 | INLINE bool atomic_compare_exchange_strong(volatile T *a, typename T::Type *cmp, | |
f35db108 WM |
75 | typename T::Type xchg, |
76 | memory_order mo) { | |
77 | typedef typename T::Type Type; | |
78 | Type cmpv = *cmp; | |
5d3805fc | 79 | Type prev; |
5d3805fc | 80 | prev = __sync_val_compare_and_swap(&a->val_dont_use, cmpv, xchg); |
5d3805fc | 81 | if (prev == cmpv) return true; |
f35db108 WM |
82 | *cmp = prev; |
83 | return false; | |
84 | } | |
85 | ||
86 | template<typename T> | |
87 | INLINE bool atomic_compare_exchange_weak(volatile T *a, | |
ef1b3fda KS |
88 | typename T::Type *cmp, |
89 | typename T::Type xchg, | |
90 | memory_order mo) { | |
f35db108 WM |
91 | return atomic_compare_exchange_strong(a, cmp, xchg, mo); |
92 | } | |
93 | ||
94 | } // namespace __sanitizer | |
95 | ||
eac97531 ML |
96 | // This include provides explicit template instantiations for atomic_uint64_t |
97 | // on MIPS32, which does not directly support 8 byte atomics. It has to | |
98 | // proceed the template definitions above. | |
99 | #if defined(_MIPS_SIM) && defined(_ABIO32) | |
100 | #include "sanitizer_atomic_clang_mips.h" | |
101 | #endif | |
102 | ||
ef1b3fda KS |
103 | #undef ATOMIC_ORDER |
104 | ||
f35db108 | 105 | #endif // SANITIZER_ATOMIC_CLANG_H |