UefiCpuPkg: Move AsmRelocateApLoopStart from Mpfuncs.nasm to AmdSev.nasm

[mirror_edk2.git] / MdePkg / Library / BaseLib / Ia32 / LRotU64.c

/** @file\r
  64-bit left rotation for Ia32\r
\r
  Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
/**\r
  Rotates a 64-bit integer left between 0 and 63 bits, filling\r
  the low bits with the high bits that were rotated.\r
\r
  This function rotates the 64-bit value Operand to the left by Count bits. The\r
  low Count bits are fill with the high Count bits of Operand. The rotated\r
  value is returned.\r
\r
  @param  Operand The 64-bit operand to rotate left.\r
  @param  Count   The number of bits to rotate left.\r
\r
  @return Operand <<< Count\r
\r
**/\r
UINT64\r
EFIAPI\r
InternalMathLRotU64 (\r
  IN      UINT64  Operand,\r
  IN      UINTN   Count\r
  )\r
{\r
  _asm {\r
    mov     cl, byte ptr [Count]\r
    mov     edx, dword ptr [Operand + 4]\r
    mov     eax, dword ptr [Operand + 0]\r
    shld    ebx, edx, cl\r
    shld    edx, eax, cl\r
    ror     ebx, cl\r
    shld    eax, ebx, cl\r
    test    cl, 32                      ; Count >= 32?\r
    jz      L0\r
    mov     ecx, eax\r
    mov     eax, edx\r
    mov     edx, ecx\r
    L0 :\r
  }\r
}\r