Re: xor as a lazy comparison

From: Paulo Marques (pmarques_at_grupopie.com)
Date: 07/25/05

  • Next message: Dmitry Torokhov: "Re: Problem with Asus P4C800-DX and P4 -Northwood-" 
    Date:	Mon, 25 Jul 2005 20:23:17 +0100
To: Lee Revell <rlrevell@joe-job.com>

    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 ;) 

    -- 
Paulo Marques - www.grupopie.com
It is a mistake to think you can solve any major problems
just with potatoes.
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  • Next message: Dmitry Torokhov: "Re: Problem with Asus P4C800-DX and P4 -Northwood-"

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