28 // Implementation of class atomic
29
30 // Implement ADD using a CAS loop.
31 template<size_t byte_size>
32 struct Atomic::PlatformAdd {
33 template<typename D, typename I>
34 inline D operator()(D volatile* dest, I add_value, atomic_memory_order order) const {
35 D old_value = *dest;
36 while (true) {
37 D new_value = old_value + add_value;
38 D result = cmpxchg(new_value, dest, old_value);
39 if (result == old_value) break;
40 old_value = result;
41 }
42 return old_value + add_value;
43 }
44 };
45
46 template<>
47 template<typename T>
48 inline T Atomic::PlatformXchg<4>::operator()(T exchange_value,
49 T volatile* dest,
50 atomic_memory_order order) const {
51 STATIC_ASSERT(4 == sizeof(T));
52 __asm__ volatile ( "swap [%2],%0"
53 : "=r" (exchange_value)
54 : "0" (exchange_value), "r" (dest)
55 : "memory");
56 return exchange_value;
57 }
58
59 template<>
60 template<typename T>
61 inline T Atomic::PlatformXchg<8>::operator()(T exchange_value,
62 T volatile* dest,
63 atomic_memory_order order) const {
64 STATIC_ASSERT(8 == sizeof(T));
65 T old_value = *dest;
66 while (true) {
67 T result = cmpxchg(exchange_value, dest, old_value);
68 if (result == old_value) break;
69 old_value = result;
70 }
71 return old_value;
72 }
73
74 // No direct support for cmpxchg of bytes; emulate using int.
75 template<>
76 struct Atomic::PlatformCmpxchg<1> : Atomic::CmpxchgByteUsingInt {};
77
78 template<>
79 template<typename T>
80 inline T Atomic::PlatformCmpxchg<4>::operator()(T exchange_value,
81 T volatile* dest,
82 T compare_value,
|
28 // Implementation of class atomic
29
30 // Implement ADD using a CAS loop.
31 template<size_t byte_size>
32 struct Atomic::PlatformAdd {
33 template<typename D, typename I>
34 inline D operator()(D volatile* dest, I add_value, atomic_memory_order order) const {
35 D old_value = *dest;
36 while (true) {
37 D new_value = old_value + add_value;
38 D result = cmpxchg(new_value, dest, old_value);
39 if (result == old_value) break;
40 old_value = result;
41 }
42 return old_value + add_value;
43 }
44 };
45
46 template<>
47 template<typename T>
48 inline T Atomic::PlatformXchg<4>::operator()(T volatile* dest,
49 T exchange_value,
50 atomic_memory_order order) const {
51 STATIC_ASSERT(4 == sizeof(T));
52 __asm__ volatile ( "swap [%2],%0"
53 : "=r" (exchange_value)
54 : "0" (exchange_value), "r" (dest)
55 : "memory");
56 return exchange_value;
57 }
58
59 template<>
60 template<typename T>
61 inline T Atomic::PlatformXchg<8>::operator()(T volatile* dest,
62 T exchange_value,
63 atomic_memory_order order) const {
64 STATIC_ASSERT(8 == sizeof(T));
65 T old_value = *dest;
66 while (true) {
67 T result = cmpxchg(exchange_value, dest, old_value);
68 if (result == old_value) break;
69 old_value = result;
70 }
71 return old_value;
72 }
73
74 // No direct support for cmpxchg of bytes; emulate using int.
75 template<>
76 struct Atomic::PlatformCmpxchg<1> : Atomic::CmpxchgByteUsingInt {};
77
78 template<>
79 template<typename T>
80 inline T Atomic::PlatformCmpxchg<4>::operator()(T exchange_value,
81 T volatile* dest,
82 T compare_value,
|