blob: 35d8437056e30d05e58d52474b5d10ea2844d4b0 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
/** @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
}
}
|
