1 /* 2 * Copyright 2013 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef SkAtomics_win_DEFINED 9 #define SkAtomics_win_DEFINED 10 11 /** Windows Interlocked atomics. */ 12 13 #include <intrin.h> 14 #include <stdint.h> 15 16 //MSDN says in order to declare an interlocked function for use as an 17 //intrinsic, include intrin.h and put the function in a #pragma intrinsic 18 //directive. 19 //The pragma appears to be unnecessary, but doesn't hurt. 20 #pragma intrinsic(_InterlockedIncrement, _InterlockedExchangeAdd, _InterlockedDecrement) 21 #pragma intrinsic(_InterlockedCompareExchange) 22 23 static inline int32_t sk_atomic_inc(int32_t* addr) { 24 // InterlockedIncrement returns the new value, we want to return the old. 25 return _InterlockedIncrement(reinterpret_cast<long*>(addr)) - 1; 26 } 27 28 static inline int32_t sk_atomic_add(int32_t* addr, int32_t inc) { 29 return _InterlockedExchangeAdd(reinterpret_cast<long*>(addr), static_cast<long>(inc)); 30 } 31 32 static inline int32_t sk_atomic_dec(int32_t* addr) { 33 // InterlockedDecrement returns the new value, we want to return the old. 34 return _InterlockedDecrement(reinterpret_cast<long*>(addr)) + 1; 35 } 36 37 static inline void sk_membar_acquire__after_atomic_dec() { } 38 39 static inline bool sk_atomic_cas(int32_t* addr, int32_t before, int32_t after) { 40 return _InterlockedCompareExchange(reinterpret_cast<long*>(addr), after, before) == before; 41 } 42 43 static inline void* sk_atomic_cas(void** addr, void* before, void* after) { 44 return InterlockedCompareExchangePointer(addr, after, before); 45 } 46 47 static inline void sk_membar_acquire__after_atomic_conditional_inc() { } 48 49 #endif 50
