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/llvm-config.h"
24 #if defined(__GNUC__) || (defined(__IBMCPP__) && __IBMCPP__ >= 1210)
28 void sys::MemoryFence() {
29 #if LLVM_HAS_ATOMICS == 0
32 # if defined(GNU_ATOMICS)
34 # elif defined(_MSC_VER)
37 # error No memory fence implementation for your platform!
42 sys::cas_flag sys::CompareAndSwap(volatile sys::cas_flag* ptr,
43 sys::cas_flag new_value,
44 sys::cas_flag old_value) {
45 #if LLVM_HAS_ATOMICS == 0
46 sys::cas_flag result = *ptr;
47 if (result == old_value)
50 #elif defined(GNU_ATOMICS)
51 return __sync_val_compare_and_swap(ptr, old_value, new_value);
52 #elif defined(_MSC_VER)
53 return InterlockedCompareExchange(ptr, new_value, old_value);
55 # error No compare-and-swap implementation for your platform!
59 sys::cas_flag sys::AtomicIncrement(volatile sys::cas_flag* ptr) {
60 #if LLVM_HAS_ATOMICS == 0
63 #elif defined(GNU_ATOMICS)
64 return __sync_add_and_fetch(ptr, 1);
65 #elif defined(_MSC_VER)
66 return InterlockedIncrement(ptr);
68 # error No atomic increment implementation for your platform!
72 sys::cas_flag sys::AtomicDecrement(volatile sys::cas_flag* ptr) {
73 #if LLVM_HAS_ATOMICS == 0
76 #elif defined(GNU_ATOMICS)
77 return __sync_sub_and_fetch(ptr, 1);
78 #elif defined(_MSC_VER)
79 return InterlockedDecrement(ptr);
81 # error No atomic decrement implementation for your platform!
85 sys::cas_flag sys::AtomicAdd(volatile sys::cas_flag* ptr, sys::cas_flag val) {
86 #if LLVM_HAS_ATOMICS == 0
89 #elif defined(GNU_ATOMICS)
90 return __sync_add_and_fetch(ptr, val);
91 #elif defined(_MSC_VER)
92 return InterlockedExchangeAdd(ptr, val) + val;
94 # error No atomic add implementation for your platform!
98 sys::cas_flag sys::AtomicMul(volatile sys::cas_flag* ptr, sys::cas_flag val) {
99 sys::cas_flag original, result;
102 result = original * val;
103 } while (sys::CompareAndSwap(ptr, result, original) != original);
108 sys::cas_flag sys::AtomicDiv(volatile sys::cas_flag* ptr, sys::cas_flag val) {
109 sys::cas_flag original, result;
112 result = original / val;
113 } while (sys::CompareAndSwap(ptr, result, original) != original);