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/** @file
64-bit right rotation for Ia32
Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
/**
Rotates a 64-bit integer right between 0 and 63 bits, filling
the high bits with the high low bits that were rotated.
This function rotates the 64-bit value Operand to the right by Count bits.
The high Count bits are fill with the low Count bits of Operand. The rotated
value is returned.
@param Operand The 64-bit operand to rotate right.
@param Count The number of bits to rotate right.
@return Operand >>> Count
**/
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?
jz L0
mov ecx, eax
mov eax, edx
mov edx, ecx
L0:
}
}
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