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Subject: Re: xor as a lazy comparison
From: Lee Revell <rlrevell@joe-job.com>
To: Paulo Marques <pmarques@grupopie.com>
Cc: Steven Rostedt <rostedt@goodmis.org>, Bernd Petrovitsch <bernd@firmix.at>,
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Date: Mon, 25 Jul 2005 15:25:35 -0400
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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...

Lee