1 // Protocol Buffers - Google's data interchange format
2 // Copyright 2015 Google Inc. All rights reserved.
3 // https://developers.google.com/protocol-buffers/
4 //
5 // Redistribution and use in source and binary forms, with or without
6 // modification, are permitted provided that the following conditions are
7 // met:
8 //
9 // * Redistributions of source code must retain the above copyright
10 // notice, this list of conditions and the following disclaimer.
11 // * Redistributions in binary form must reproduce the above
12 // copyright notice, this list of conditions and the following disclaimer
13 // in the documentation and/or other materials provided with the
14 // distribution.
15 // * Neither the name of Google Inc. nor the names of its
16 // contributors may be used to endorse or promote products derived from
17 // this software without specific prior written permission.
18 //
19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
31 // Author: ogabbay@advaoptical.com (Oded Gabbay)
32 // Cleaned up by: bsilver16384@gmail.com (Brian Silverman)
33 //
34 // This file is an internal atomic implementation, use atomicops.h instead.
35
36 #ifndef GOOGLE_PROTOBUF_ATOMICOPS_INTERNALS_PPC_GCC_H_
37 #define GOOGLE_PROTOBUF_ATOMICOPS_INTERNALS_PPC_GCC_H_
38
39 #define ATOMICOPS_COMPILER_BARRIER() __asm__ __volatile__("" : : : "memory")
40
41 namespace google {
42 namespace protobuf {
43 namespace internal {
44
NoBarrier_CompareAndSwap(volatile Atomic32 * ptr,Atomic32 old_value,Atomic32 new_value)45 inline Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32 *ptr,
46 Atomic32 old_value,
47 Atomic32 new_value) {
48 Atomic32 prev;
49
50 __asm__ __volatile__(
51 "0: \n\t"
52 "lwarx %[prev],0,%[ptr] \n\t"
53 "cmpw 0,%[prev],%[old_value] \n\t"
54 "bne- 1f \n\t"
55 "stwcx. %[new_value],0,%[ptr] \n\t"
56 "bne- 0b \n\t"
57 "1: \n\t"
58 : [prev] "=&r"(prev), "+m"(*ptr)
59 : [ptr] "r"(ptr), [old_value] "r"(old_value), [new_value] "r"(new_value)
60 : "cc", "memory");
61
62 return prev;
63 }
64
NoBarrier_AtomicExchange(volatile Atomic32 * ptr,Atomic32 new_value)65 inline Atomic32 NoBarrier_AtomicExchange(volatile Atomic32 *ptr,
66 Atomic32 new_value) {
67 Atomic32 old;
68
69 __asm__ __volatile__(
70 "0: \n\t"
71 "lwarx %[old],0,%[ptr] \n\t"
72 "stwcx. %[new_value],0,%[ptr] \n\t"
73 "bne- 0b \n\t"
74 : [old] "=&r"(old), "+m"(*ptr)
75 : [ptr] "r"(ptr), [new_value] "r"(new_value)
76 : "cc", "memory");
77
78 return old;
79 }
80
NoBarrier_AtomicIncrement(volatile Atomic32 * ptr,Atomic32 increment)81 inline Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32 *ptr,
82 Atomic32 increment) {
83 Atomic32 temp;
84
85 __asm__ __volatile__(
86 "0: \n\t"
87 "lwarx %[temp],0,%[ptr] \n\t"
88 "add %[temp],%[increment],%[temp] \n\t"
89 "stwcx. %[temp],0,%[ptr] \n\t"
90 "bne- 0b \n\t"
91 : [temp] "=&r"(temp)
92 : [increment] "r"(increment), [ptr] "r"(ptr)
93 : "cc", "memory");
94
95 return temp;
96 }
97
Barrier_AtomicIncrement(volatile Atomic32 * ptr,Atomic32 increment)98 inline Atomic32 Barrier_AtomicIncrement(volatile Atomic32 *ptr,
99 Atomic32 increment) {
100 MemoryBarrier();
101 Atomic32 res = NoBarrier_AtomicIncrement(ptr, increment);
102 MemoryBarrier();
103 return res;
104 }
105
Acquire_CompareAndSwap(volatile Atomic32 * ptr,Atomic32 old_value,Atomic32 new_value)106 inline Atomic32 Acquire_CompareAndSwap(volatile Atomic32 *ptr,
107 Atomic32 old_value, Atomic32 new_value) {
108 Atomic32 res = NoBarrier_CompareAndSwap(ptr, old_value, new_value);
109 MemoryBarrier();
110 return res;
111 }
112
Release_CompareAndSwap(volatile Atomic32 * ptr,Atomic32 old_value,Atomic32 new_value)113 inline Atomic32 Release_CompareAndSwap(volatile Atomic32 *ptr,
114 Atomic32 old_value, Atomic32 new_value) {
115 MemoryBarrier();
116 Atomic32 res = NoBarrier_CompareAndSwap(ptr, old_value, new_value);
117 return res;
118 }
119
NoBarrier_Store(volatile Atomic32 * ptr,Atomic32 value)120 inline void NoBarrier_Store(volatile Atomic32 *ptr, Atomic32 value) {
121 *ptr = value;
122 }
123
MemoryBarrier()124 inline void MemoryBarrier() { __asm__ __volatile__("sync" : : : "memory"); }
125
Acquire_Store(volatile Atomic32 * ptr,Atomic32 value)126 inline void Acquire_Store(volatile Atomic32 *ptr, Atomic32 value) {
127 *ptr = value;
128 MemoryBarrier();
129 }
130
Release_Store(volatile Atomic32 * ptr,Atomic32 value)131 inline void Release_Store(volatile Atomic32 *ptr, Atomic32 value) {
132 MemoryBarrier();
133 *ptr = value;
134 }
135
NoBarrier_Load(volatile const Atomic32 * ptr)136 inline Atomic32 NoBarrier_Load(volatile const Atomic32 *ptr) { return *ptr; }
137
Acquire_Load(volatile const Atomic32 * ptr)138 inline Atomic32 Acquire_Load(volatile const Atomic32 *ptr) {
139 Atomic32 value = *ptr;
140 MemoryBarrier();
141 return value;
142 }
143
Release_Load(volatile const Atomic32 * ptr)144 inline Atomic32 Release_Load(volatile const Atomic32 *ptr) {
145 MemoryBarrier();
146 return *ptr;
147 }
148
149 } // namespace internal
150 } // namespace protobuf
151 } // namespace google
152
153 #undef ATOMICOPS_COMPILER_BARRIER
154
155 #endif // GOOGLE_PROTOBUF_ATOMICOPS_INTERNALS_PPC_GCC_H_
156