Re: xor as a lazy comparison

From: Lee Revell
Date: Mon Jul 25 2005 - 14:31:58 EST

On Mon, 2005-07-25 at 20:23 +0100, Paulo Marques wrote:
> Lee Revell wrote:
> > On Mon, 2005-07-25 at 13:55 -0400, Steven Rostedt wrote:
> >
> >>Doesn't matter. The cycles saved for old compilers is not rational to
> >>have obfuscated code.
> >
> > Where do we draw the line with this? Is x *= 2 preferable to x <<= 2 as
> > well?
> I guess this depends on what you logically want to do. If the problem
> requires you to shift some value N bits, then you should use a shift
> operation.
> If what you want is to multiply a value by a certain ammount, you should
> just use a multiplication.
> Using a shift to perform the multiplication should be left to the
> compiler IMHO.
> The proof that the shift is not so clear is that even you got the shift
> wrong in your own example ;)

Yeah, that was going to be my point, but I made it inadvertently before
I even got that far...


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