From: Charles Forsyth <charles.forsyth@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: Re: [9fans] subtracting pointers on amd64 6c
Date: Tue, 5 Jan 2016 10:15:10 +0000 [thread overview]
Message-ID: <CAOw7k5h2J25XBe3_+m6PiyzuS_yzwEx0dncB5STTFomf3DBtGg@mail.gmail.com> (raw)
In-Reply-To: <8edba5d726ee6a032d8521c7de33f499@felloff.net>
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On 5 January 2016 at 06:36, <cinap_lenrek@felloff.net> wrote:
> 1) why do we cast to long?
>
because that's the type all existing code expected, and there wasn't much
application
for > 4gb in single arrays at the time (as opposed to having big memory in
big address spaces)
> 2) if a pointer subtraction has to yield a long, why dont we cast *after*
> the division?
>
that would be certainly be better.
having said that, because of caching effects, especially on NUMA, it's
worth looking at data structures that
big to decide whether they might be better organised less naively.
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next prev parent reply other threads:[~2016-01-05 10:15 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-05 6:36 cinap_lenrek
2016-01-05 7:53 ` cinap_lenrek
2016-01-05 10:17 ` Charles Forsyth
2016-01-05 10:15 ` Charles Forsyth [this message]
2016-01-05 10:28 ` Charles Forsyth
2016-01-05 19:01 ` Devon H. O'Dell
2016-01-05 19:46 ` Charles Forsyth
2016-01-05 20:40 ` erik quanstrom
2016-01-05 21:53 ` Devon H. O'Dell
2016-01-05 23:27 ` erik quanstrom
2016-01-05 23:37 ` Dave Eckhardt
2016-01-05 21:03 ` erik quanstrom
2016-01-05 22:32 ` cinap_lenrek
2016-01-05 22:57 ` Devon H. O'Dell
2016-01-05 23:17 ` Devon H. O'Dell
2016-01-05 23:14 ` erik quanstrom
2016-01-06 6:58 ` cinap_lenrek
2016-01-06 19:10 ` erik quanstrom
2016-01-07 1:08 ` cinap_lenrek
2016-01-08 22:23 ` erik quanstrom
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