MdePkg/Library/BaseSynchronizationLib/InterlockedDecrementMsc.c

   1 /** @file
   2   InterlockedDecrement function
   3
   4   Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 /**
  10   Microsoft Visual Studio 7.1 Function Prototypes for I/O Intrinsics.
  11 **/
  12
  13 long _InterlockedDecrement(
  14    long * lpAddend
  15 );
  16
  17 #pragma intrinsic(_InterlockedDecrement)
  18
  19 /**
  20   Performs an atomic decrement of an 32-bit unsigned integer.
  21
  22   Performs an atomic decrement of the 32-bit unsigned integer specified by
  23   Value and returns the decrement value. The decrement operation must be
  24   performed using MP safe mechanisms. The state of the return value is not
  25   guaranteed to be MP safe.
  26
  27   @param  Value A pointer to the 32-bit value to decrement.
  28
  29   @return The decrement value.
  30
  31 **/
  32 UINT32
  33 EFIAPI
  34 InternalSyncDecrement (
  35   IN      volatile UINT32           *Value
  36   )
  37 {
  38   return _InterlockedDecrement ((long *)(Value));
  39 }
  40