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/** @file
  AsmWriteCr4 function

  Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

/**
  Writes a value to Control Register 4 (CR4).

  Writes and returns a new value to CR4. This function is only available on
  IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.

  @param  Value The value to write to CR4.

  @return The value written to CR4.

**/
UINTN
EFIAPI
AsmWriteCr4 (
  UINTN  Value
  )
{
  _asm {
    mov     eax, Value
    _emit  0x0f  // mov  cr4, eax
    _emit  0x22
    _emit  0xE0
  }
}