| /* |
| * Copyright (c) 2019, The Linux Foundation. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following |
| * disclaimer in the documentation and/or other materials provided |
| * with the distribution. |
| * * Neither the name of The Linux Foundation nor the names of its |
| * contributors may be used to endorse or promote products derived |
| * from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS |
| * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR |
| * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE |
| * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN |
| * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| #include "AEEatomic.h" |
| |
| uint32 atomic_Add(uint32 * volatile puDest, int nAdd) { |
| uint32 previous; |
| uint32 current; |
| do { |
| current = *puDest; |
| previous = atomic_CompareAndExchange(puDest, current + nAdd, current); |
| } while(previous != current); |
| return (current + nAdd); |
| } |
| |
| uint32 atomic_Exchange(uint32* volatile puDest, uint32 uVal) { |
| uint32 previous; |
| uint32 current; |
| do { |
| current = *puDest; |
| previous = atomic_CompareAndExchange(puDest, uVal, current); |
| } while(previous != current); |
| return previous; |
| } |
| |
| uint32 atomic_CompareOrAdd(uint32* volatile puDest, uint32 uCompare, int nAdd) { |
| uint32 previous; |
| uint32 current; |
| uint32 result; |
| do { |
| current = *puDest; |
| previous = current; |
| result = current; |
| if(current != uCompare) { |
| previous = atomic_CompareAndExchange(puDest, current + nAdd, current); |
| if(previous == current) { |
| result = current + nAdd; |
| } |
| } |
| } while(previous != current); |
| return result; |
| } |
| |