Re: passing class to a function in c++ - performance question

From: Karl Heinz Buchegger (kbuchegg_at_gascad.at)
Date: 03/30/05 

Date: Wed, 30 Mar 2005 13:09:45 +0200

Profil1 wrote:
>
> Hi,
> I'm writing a code that has to be as efficient as possible both in terms of
> memory use and execution speed. I'll have to pass a class instance (which is
> an 'intelligent' array) to a function (multiple times). Taking this into
> consideration, should I pass it as a pointer or reference? Is there any book
> or site that teaches stuff like this (optimizing code for performance)?
> thanks for any help

There is only one way to figure out: Time it.

But usually both methods (pass by pointer, pass per reference)
have equal performance. This is so, because the compiler implements
'pass per reference' by passing a pointer under the hood. So in
the end it turns out, that you do the very same thing with different
syntax. 

-- 
Karl Heinz Buchegger
kbuchegg@gascad.at

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