MdePkg/Library/BaseLib/Ia32/ReadGs.c

   1 /** @file
   2   AsmReadGs function
   3
   4   Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 /**
  10   Reads the current value of GS Data Segment Register (GS).
  11
  12   Reads and returns the current value of GS. This function is only available on
  13   IA-32 and x64.
  14
  15   @return The current value of GS.
  16
  17 **/
  18 UINT16
  19 EFIAPI
  20 AsmReadGs (
  21   VOID
  22   )
  23 {
  24   __asm {
  25     xor     eax, eax
  26     mov     ax, gs
  27   }
  28 }