MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange64.S

   1 #------------------------------------------------------------------------------
   2 #
   3 # Copyright (c) 2006 - 2009, Intel Corporation
   4 # All rights reserved. This program and the accompanying materials
   5 # are licensed and made available under the terms and conditions of the BSD License
   6 # which accompanies this distribution.  The full text of the license may be found at
   7 # http://opensource.org/licenses/bsd-license.php
   8 #
   9 # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11 #
  12 # Module Name:
  13 #
  14 #   InterlockedCompareExchange64.S
  15 #
  16 # Abstract:
  17 #
  18 #   InterlockedCompareExchange64 function
  19 #
  20 # Notes:
  21 #
  22 #------------------------------------------------------------------------------
  23
  24
  25 #------------------------------------------------------------------------------
  26 # UINT64
  27 # EFIAPI
  28 # InterlockedCompareExchange64 (
  29 #   IN      UINT64                    *Value,
  30 #   IN      UINT64                    CompareValue,
  31 #   IN      UINT64                    ExchangeValue
  32 #   );
  33 #------------------------------------------------------------------------------
  34 ASM_GLOBAL ASM_PFX(InternalSyncCompareExchange64)
  35 ASM_PFX(InternalSyncCompareExchange64):
  36     mov     %rdx, %rax
  37     lock/cmpxchg %r8,(%rcx)
  38     ret