mirror of
https://github.com/CloverHackyColor/CloverBootloader.git
synced 2024-12-21 15:57:42 +01:00
45 lines
1.4 KiB
C
45 lines
1.4 KiB
C
|
/** @file
|
||
|
InterlockedCompareExchange64 function
|
||
|
|
||
|
Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
|
||
|
SPDX-License-Identifier: BSD-2-Clause-Patent
|
||
|
|
||
|
**/
|
||
|
|
||
|
|
||
|
|
||
|
|
||
|
/**
|
||
|
Performs an atomic compare exchange operation on a 64-bit unsigned integer.
|
||
|
|
||
|
Performs an atomic compare exchange operation on the 64-bit unsigned integer specified
|
||
|
by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and
|
||
|
CompareValue is returned. If Value is not equal to CompareValue, then Value is returned.
|
||
|
The compare exchange operation must be performed using MP safe mechanisms.
|
||
|
|
||
|
@param Value A pointer to the 64-bit value for the compare exchange
|
||
|
operation.
|
||
|
@param CompareValue A 64-bit value used in a compare operation.
|
||
|
@param ExchangeValue A 64-bit value used in an exchange operation.
|
||
|
|
||
|
@return The original *Value before exchange.
|
||
|
|
||
|
**/
|
||
|
UINT64
|
||
|
EFIAPI
|
||
|
InternalSyncCompareExchange64 (
|
||
|
IN volatile UINT64 *Value,
|
||
|
IN UINT64 CompareValue,
|
||
|
IN UINT64 ExchangeValue
|
||
|
)
|
||
|
{
|
||
|
_asm {
|
||
|
mov esi, Value
|
||
|
mov eax, dword ptr [CompareValue + 0]
|
||
|
mov edx, dword ptr [CompareValue + 4]
|
||
|
mov ebx, dword ptr [ExchangeValue + 0]
|
||
|
mov ecx, dword ptr [ExchangeValue + 4]
|
||
|
lock cmpxchg8b qword ptr [esi]
|
||
|
}
|
||
|
}
|