1 //===-- Atomic.cpp - Atomic Operations --------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This header file implements atomic operations.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Support/Atomic.h"
15 #include "llvm/Config/config.h"
16 #if defined(ANDROID_TARGET_BUILD)
17 # include "sys/atomics.h"
27 void sys::MemoryFence() {
28 #if LLVM_MULTITHREADED==0
31 # if defined(__GNUC__)
33 # elif defined(_MSC_VER)
36 # error No memory fence implementation for your platform!
41 sys::cas_flag sys::CompareAndSwap(volatile sys::cas_flag* ptr,
42 sys::cas_flag new_value,
43 sys::cas_flag old_value) {
44 #if LLVM_MULTITHREADED==0
45 sys::cas_flag result = *ptr;
46 if (result == old_value)
49 #elif defined(ANDROID_TARGET_BUILD)
50 return __atomic_cmpxchg(old_value, new_value, (volatile int*)ptr);
51 #elif defined(__GNUC__)
52 return __sync_val_compare_and_swap(ptr, old_value, new_value);
53 #elif defined(_MSC_VER)
54 return InterlockedCompareExchange(ptr, new_value, old_value);
56 # error No compare-and-swap implementation for your platform!
60 sys::cas_flag sys::AtomicIncrement(volatile sys::cas_flag* ptr) {
61 #if LLVM_MULTITHREADED==0
64 #elif defined(ANDROID_TARGET_BUILD)
65 return __atomic_inc((volatile int*)ptr);
66 #elif defined(__GNUC__)
67 return __sync_add_and_fetch(ptr, 1);
68 #elif defined(_MSC_VER)
69 return InterlockedIncrement(ptr);
71 # error No atomic increment implementation for your platform!
75 sys::cas_flag sys::AtomicDecrement(volatile sys::cas_flag* ptr) {
76 #if LLVM_MULTITHREADED==0
79 #elif defined(ANDROID_TARGET_BUILD)
80 return __atomic_dec((volatile int*)ptr);
81 #elif defined(__GNUC__)
82 return __sync_sub_and_fetch(ptr, 1);
83 #elif defined(_MSC_VER)
84 return InterlockedDecrement(ptr);
86 # error No atomic decrement implementation for your platform!
90 sys::cas_flag sys::AtomicAdd(volatile sys::cas_flag* ptr, sys::cas_flag val) {
91 #if LLVM_MULTITHREADED==0
94 #elif defined(ANDROID_TARGET_BUILD)
95 sys::cas_flag original, result;
98 result = original + val;
99 } while (__atomic_cmpxchg(original, result, (volatile int*)ptr) != original);
101 #elif defined(__GNUC__)
102 return __sync_add_and_fetch(ptr, val);
103 #elif defined(_MSC_VER)
104 return InterlockedExchangeAdd(ptr, val) + val;
106 # error No atomic add implementation for your platform!
110 sys::cas_flag sys::AtomicMul(volatile sys::cas_flag* ptr, sys::cas_flag val) {
111 sys::cas_flag original, result;
114 result = original * val;
115 } while (sys::CompareAndSwap(ptr, result, original) != original);
120 sys::cas_flag sys::AtomicDiv(volatile sys::cas_flag* ptr, sys::cas_flag val) {
121 sys::cas_flag original, result;
124 result = original / val;
125 } while (sys::CompareAndSwap(ptr, result, original) != original);