OvmfPkg/XenBusDxe/Ia32/InterlockedCompareExchange16.nasm

   1 ;------------------------------------------------------------------------------
   2 ;
   3 ; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
   4 ; 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 ;   InterlockedCompareExchange16.Asm
  15 ;
  16 ; Abstract:
  17 ;
  18 ;   InterlockedCompareExchange16 function
  19 ;
  20 ; Notes:
  21 ;
  22 ;------------------------------------------------------------------------------
  23
  24     SECTION .text
  25
  26 ;------------------------------------------------------------------------------
  27 ; UINT32
  28 ; EFIAPI
  29 ; InternalSyncCompareExchange16 (
  30 ;   IN      UINT16                    *Value,
  31 ;   IN      UINT16                    CompareValue,
  32 ;   IN      UINT16                    ExchangeValue
  33 ;   );
  34 ;------------------------------------------------------------------------------
  35 global ASM_PFX(InternalSyncCompareExchange16)
  36 ASM_PFX(InternalSyncCompareExchange16):
  37     mov     ecx, [esp + 4]
  38     mov     eax, [esp + 8]
  39     mov     edx, [esp + 12]
  40     lock    cmpxchg [ecx], dx
  41     ret
  42