audk/MdePkg/Library/BaseLib/Ia32/RRotU64.c

42 lines
1.1 KiB
C

/** @file
64-bit right rotation for Ia32
Copyright (c) 2006 - 2007, Intel Corporation<BR>
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
//
// Include common header file for this module.
//
UINT64
EFIAPI
InternalMathRRotU64 (
IN UINT64 Operand,
IN UINTN Count
)
{
_asm {
mov cl, byte ptr [Count]
mov eax, dword ptr [Operand + 0]
mov edx, dword ptr [Operand + 4]
shrd ebx, eax, cl
shrd eax, edx, cl
rol ebx, cl
shrd edx, ebx, cl
test cl, 32 // Count >= 32?
cmovnz ecx, eax
cmovnz eax, edx
cmovnz edx, ecx
}
}