mirror of
https://github.com/CloverHackyColor/CloverBootloader.git
synced 2024-12-27 16:58:09 +01:00
46 lines
1.0 KiB
C
46 lines
1.0 KiB
C
|
/** @file
|
||
|
|
64-bit logical right shift function for IA-32
|
||
|
|
|
||
|
|
Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
|
||
|
|
SPDX-License-Identifier: BSD-2-Clause-Patent
|
||
|
|
|
||
|
|
**/
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
Shifts a 64-bit integer right between 0 and 63 bits. This high bits
|
||
|
|
are filled with zeros. The shifted value is returned.
|
||
|
|
|
||
|
|
This function shifts the 64-bit value Operand to the right by Count bits. The
|
||
|
|
high Count bits are set to zero. The shifted value is returned.
|
||
|
|
|
||
|
|
@param Operand The 64-bit operand to shift right.
|
||
|
|
@param Count The number of bits to shift right.
|
||
|
|
|
||
|
|
@return Operand >> Count
|
||
|
|
|
||
|
|
**/
|
||
|
|
UINT64
|
||
|
|
EFIAPI
|
||
|
|
InternalMathRShiftU64 (
|
||
|
|
IN UINT64 Operand,
|
||
|
|
IN UINTN Count
|
||
|
|
)
|
||
|
|
{
|
||
|
|
_asm {
|
||
|
|
mov cl, byte ptr [Count]
|
||
|
|
xor edx, edx
|
||
|
|
mov eax, dword ptr [Operand + 4]
|
||
|
|
test cl, 32
|
||
|
|
jnz L0
|
||
|
|
mov edx, eax
|
||
|
|
mov eax, dword ptr [Operand + 0]
|
||
|
|
L0:
|
||
|
|
shrd eax, edx, cl
|
||
|
|
shr edx, cl
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|