Re: xor as a lazy comparison

From: Jan Engelhardt
Date: Tue Jul 26 2005 - 01:09:12 EST

>> > Where do we draw the line with this? Is x *= 2 preferable to x <<= 2 as
>> > well?
>> Depends if you want to multiply by 2 or 4 :-)
>I guess I just answered my own question ;-)

To answer for x *= 2 vs x <<= 1:

Use * when you would logically want to do a multiplication,
<< if you're working on a bitfield. It's just for keeping the code clean
enough so that others may understand it.

In the longshot, it does not matter, as gcc will optimize out multiplication
with powers of two to bitops.

Jan Engelhardt
| Alphagate Systems,
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