Re: which way is faster?

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Arjan van de Ven wrote:
> On Mon, 2006-12-18 at 17:12 -0500, Ming Zhang wrote:
>> See this code piece
>>
>> http://lxr.linux.no/source/drivers/scsi/libata-scsi.c?v=2.6.18#L1049
>>
>> 1056         lba |= ((u64)scsicmd[2]) << 24;
>> 1057         lba |= ((u64)scsicmd[3]) << 16;
>> 1058         lba |= ((u64)scsicmd[4]) << 8;
>> 1059         lba |= ((u64)scsicmd[5]);
>>
>> it can also be written as 
>>
>> lba = be32_to_cpu(*(u32 *)(&scsicmd[2])

ISO/IEC 9899:1999(E) "6.5 Expressions" [#7]

For example, what is the alignment of ``scsicmd'' ?

~velco


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