Re: [9fans] integer width on AMD64 (was: Re: AMD64 system)

[Comeau At9Fans <comeauat9fans@gmail.com>]

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On Mon, May 7, 2012 at 8:44 AM, erik quanstrom <quanstro@quanstro.net>wrote:

> ...
>        processor bw >> memory bw  ==> smaller integers faster
>        memory bw >> processor bw  ==> natural integers faster
>
> (this is yet another reason that int_fast* are a half-baked idea.
> how does the compiler know this relation for the target machine
> ahead of time?) ...
>

I think that is all so, and I'm not necessarily trying to defend its
problems, but on the same note, similar assumptions are also make about
int, and it can be argued that int_fast* etc just become par for that
course, especially given that there may be command line arguments allowing
the user to give some of these things a poke so to speak.  And this is not
alone in those kinds of things (which are probably not even really
engineering compromises), for instance, take malloc.

--
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