1/*
2 * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
24
25#ifndef OS_CPU_LINUX_X86_ATOMIC_LINUX_X86_HPP
26#define OS_CPU_LINUX_X86_ATOMIC_LINUX_X86_HPP
27
28// Implementation of class atomic
29
30template<size_t byte_size>
31struct Atomic::PlatformAdd
32 : Atomic::FetchAndAdd<Atomic::PlatformAdd<byte_size> >
33{
34 template<typename I, typename D>
35 D fetch_and_add(I add_value, D volatile* dest, atomic_memory_order order) const;
36};
37
38template<>
39template<typename I, typename D>
40inline D Atomic::PlatformAdd<4>::fetch_and_add(I add_value, D volatile* dest,
41 atomic_memory_order order) const {
42 STATIC_ASSERT(4 == sizeof(I));
43 STATIC_ASSERT(4 == sizeof(D));
44 D old_value;
45 __asm__ volatile ( "lock xaddl %0,(%2)"
46 : "=r" (old_value)
47 : "0" (add_value), "r" (dest)
48 : "cc", "memory");
49 return old_value;
50}
51
52template<>
53template<typename T>
54inline T Atomic::PlatformXchg<4>::operator()(T exchange_value,
55 T volatile* dest,
56 atomic_memory_order order) const {
57 STATIC_ASSERT(4 == sizeof(T));
58 __asm__ volatile ( "xchgl (%2),%0"
59 : "=r" (exchange_value)
60 : "0" (exchange_value), "r" (dest)
61 : "memory");
62 return exchange_value;
63}
64
65template<>
66template<typename T>
67inline T Atomic::PlatformCmpxchg<1>::operator()(T exchange_value,
68 T volatile* dest,
69 T compare_value,
70 atomic_memory_order /* order */) const {
71 STATIC_ASSERT(1 == sizeof(T));
72 __asm__ volatile ("lock cmpxchgb %1,(%3)"
73 : "=a" (exchange_value)
74 : "q" (exchange_value), "a" (compare_value), "r" (dest)
75 : "cc", "memory");
76 return exchange_value;
77}
78
79template<>
80template<typename T>
81inline T Atomic::PlatformCmpxchg<4>::operator()(T exchange_value,
82 T volatile* dest,
83 T compare_value,
84 atomic_memory_order /* order */) const {
85 STATIC_ASSERT(4 == sizeof(T));
86 __asm__ volatile ("lock cmpxchgl %1,(%3)"
87 : "=a" (exchange_value)
88 : "r" (exchange_value), "a" (compare_value), "r" (dest)
89 : "cc", "memory");
90 return exchange_value;
91}
92
93#ifdef AMD64
94
95template<>
96template<typename I, typename D>
97inline D Atomic::PlatformAdd<8>::fetch_and_add(I add_value, D volatile* dest,
98 atomic_memory_order order) const {
99 STATIC_ASSERT(8 == sizeof(I));
100 STATIC_ASSERT(8 == sizeof(D));
101 D old_value;
102 __asm__ __volatile__ ("lock xaddq %0,(%2)"
103 : "=r" (old_value)
104 : "0" (add_value), "r" (dest)
105 : "cc", "memory");
106 return old_value;
107}
108
109template<>
110template<typename T>
111inline T Atomic::PlatformXchg<8>::operator()(T exchange_value, T volatile* dest,
112 atomic_memory_order order) const {
113 STATIC_ASSERT(8 == sizeof(T));
114 __asm__ __volatile__ ("xchgq (%2),%0"
115 : "=r" (exchange_value)
116 : "0" (exchange_value), "r" (dest)
117 : "memory");
118 return exchange_value;
119}
120
121template<>
122template<typename T>
123inline T Atomic::PlatformCmpxchg<8>::operator()(T exchange_value,
124 T volatile* dest,
125 T compare_value,
126 atomic_memory_order /* order */) const {
127 STATIC_ASSERT(8 == sizeof(T));
128 __asm__ __volatile__ ("lock cmpxchgq %1,(%3)"
129 : "=a" (exchange_value)
130 : "r" (exchange_value), "a" (compare_value), "r" (dest)
131 : "cc", "memory");
132 return exchange_value;
133}
134
135#else // !AMD64
136
137extern "C" {
138 // defined in linux_x86.s
139 int64_t _Atomic_cmpxchg_long(int64_t, volatile int64_t*, int64_t);
140 void _Atomic_move_long(const volatile int64_t* src, volatile int64_t* dst);
141}
142
143template<>
144template<typename T>
145inline T Atomic::PlatformCmpxchg<8>::operator()(T exchange_value,
146 T volatile* dest,
147 T compare_value,
148 atomic_memory_order order) const {
149 STATIC_ASSERT(8 == sizeof(T));
150 return cmpxchg_using_helper<int64_t>(_Atomic_cmpxchg_long, exchange_value, dest, compare_value);
151}
152
153template<>
154template<typename T>
155inline T Atomic::PlatformLoad<8>::operator()(T const volatile* src) const {
156 STATIC_ASSERT(8 == sizeof(T));
157 volatile int64_t dest;
158 _Atomic_move_long(reinterpret_cast<const volatile int64_t*>(src), reinterpret_cast<volatile int64_t*>(&dest));
159 return PrimitiveConversions::cast<T>(dest);
160}
161
162template<>
163template<typename T>
164inline void Atomic::PlatformStore<8>::operator()(T store_value,
165 T volatile* dest) const {
166 STATIC_ASSERT(8 == sizeof(T));
167 _Atomic_move_long(reinterpret_cast<const volatile int64_t*>(&store_value), reinterpret_cast<volatile int64_t*>(dest));
168}
169
170#endif // AMD64
171
172#endif // OS_CPU_LINUX_X86_ATOMIC_LINUX_X86_HPP
173