]>
git.proxmox.com Git - mirror_edk2.git/blob - EdkCompatibilityPkg/Foundation/Library/EdkIIGlueLib/Library/BaseLib/HighBitSet64.c
3 Copyright (c) 2004 - 2006, Intel Corporation
4 All rights reserved. This program and the accompanying materials
5 are licensed and made available under the terms and conditions of the BSD License
6 which accompanies this distribution. The full text of the license may be found at
7 http://opensource.org/licenses/bsd-license.php
9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
19 Math worker functions.
23 #include "BaseLibInternals.h"
26 Returns the bit position of the highest bit set in a 64-bit value. Equivalent
29 This function computes the bit position of the highest bit set in the 64-bit
30 value specified by Operand. If Operand is zero, then -1 is returned.
31 Otherwise, a value between 0 and 63 is returned.
33 @param Operand The 64-bit operand to evaluate.
35 @return Position of the highest bit set in Operand if found.
36 @retval -1 Operand is zero.
45 if (Operand
== (UINT32
)Operand
) {
47 // Operand is just a 32-bit integer
49 return HighBitSet32 ((UINT32
)Operand
);
53 // Operand is really a 64-bit integer
55 if (sizeof (UINTN
) == sizeof (UINT32
)) {
56 return HighBitSet32 (((UINT32
*)&Operand
)[1]) + 32;
58 return HighBitSet32 ((UINT32
)RShiftU64 (Operand
, 32)) + 32;