1 /** @file
2 InterlockedCompareExchange32 function
3
4 Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
5 This program and the accompanying materials
6 are licensed and made available under the terms and conditions of the BSD License
7 which accompanies this distribution. The full text of the license may be found at
8 http://opensource.org/licenses/bsd-license.php.
9
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
12
13 **/
14
15 /**
16 Microsoft Visual Studio 7.1 Function Prototypes for I/O Intrinsics.
17 **/
18
19 long _InterlockedCompareExchange(
20 long volatile * Destination,
21 long Exchange,
22 long Comperand
23 );
24
25 #pragma intrinsic(_InterlockedCompareExchange)
26
27 /**
28 Performs an atomic compare exchange operation on a 32-bit unsigned integer.
29
30 Performs an atomic compare exchange operation on the 32-bit unsigned integer
31 specified by Value. If Value is equal to CompareValue, then Value is set to
32 ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue,
33 then Value is returned. The compare exchange operation must be performed using
34 MP safe mechanisms.
35
36 @param Value A pointer to the 32-bit value for the compare exchange
37 operation.
38 @param CompareValue 32-bit value used in compare operation.
39 @param ExchangeValue 32-bit value used in exchange operation.
40
41 @return The original *Value before exchange.
42
43 **/
44 UINT32
45 EFIAPI
InternalSyncCompareExchange32(IN UINT32 * Value,IN UINT32 CompareValue,IN UINT32 ExchangeValue)46 InternalSyncCompareExchange32 (
47 IN UINT32 *Value,
48 IN UINT32 CompareValue,
49 IN UINT32 ExchangeValue
50 )
51 {
52 return _InterlockedCompareExchange (Value, ExchangeValue, CompareValue);
53 }
54
55