Re: * 4 converted to << 2 for networking code

Mike Harrold (mharrold@cas.org)
Wed, 10 Jan 2001 11:26:01 -0500 (EST)


>
> Mike Harrold wrote:
> > Be careful. *4 is not a simple <<2 substitution (by the compiler) if
> > the variable is signed. *4 translates to 3 instructions (on x86) if
> > it's an int.
>
> I think you mean /4 is not the same as >>2 if the variable is signed.
>
> In general, non-widening multiplies give the same result for signed and
> unsigned variables.
>

I believe you're right. Teach me to post before morning coffee :)

/Mike

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