From: Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP>
Subject: Re: Forcing GNAT to use 32-bit load/store instructions on ARM?
Date: Thu, 10 Jul 2014 00:11:11 +0000 (UTC)
Date: 2014-07-10T00:11:11+00:00 [thread overview]
Message-ID: <lpklmu$evl$1@dont-email.me> (raw)
In-Reply-To: 1l6z27vulrv65.1xwdi0b9yactc$.dlg@40tude.net
On 2014-07-09, Dmitry A. Kazakov <mailbox@dmitry-kazakov.de> wrote:
> On Tue, 8 Jul 2014 15:34:04 -0500, Randy Brukardt wrote:
>
>> To make
>> "Read-Modify-Write" indivisible, you'd need a test-and-set instruction,
>> which would require far more restrictions than Atomic does. (I don't see any
>> way to make a general Read-Modify-Write to be indivisible on Windows or
>> Linux, for instance, as that requires shutting off interrupts.)
>
> I don't think this should be the semantics of "indivisible". Because as you
> said it incredibly difficult to ensure, but more importantly is that this
> is mot what programmers actually need. They need it rather be logically
> indivisible from the process' point of view. If the process could lose the
> processor in between would be no problem for most if not all applications.
>
Oh, I agree with this. :-)
I was just wondering if a newcomer to Ada might be confused by the
use of the word Atomic.
BTW, I'm planning on writing up the partial aggregate submission
sometime at the weekend (spare time permitting :-)).
I'm also planning on a second submission which is a request for a
formal decision regarding if Atomic on a record applies to the access
of a individual record component or not.
The wording identified by Niklas ("as a whole") would suggest not
but Randy appears to think it does. I think we need a firm decision
one way or another so we know for sure.
Simon.
--
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world
next prev parent reply other threads:[~2014-07-10 0:11 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-30 22:11 Forcing GNAT to use 32-bit load/store instructions on ARM? daniel.dmk
2014-06-30 23:41 ` Jeffrey Carter
2014-07-01 12:06 ` Simon Clubley
2014-07-01 15:44 ` Niklas Holsti
2014-07-01 17:26 ` Simon Clubley
2014-07-01 17:18 ` Simon Wright
2014-07-01 19:43 ` Simon Wright
2014-07-01 17:28 ` Jeffrey Carter
2014-07-01 0:55 ` anon
2014-07-01 4:30 ` Niklas Holsti
2014-07-01 8:11 ` Dmitry A. Kazakov
2014-07-01 12:09 ` Simon Clubley
2014-07-01 12:20 ` Dmitry A. Kazakov
2014-07-01 17:00 ` Simon Clubley
2014-07-01 19:36 ` Dmitry A. Kazakov
2014-07-01 20:08 ` Simon Clubley
2014-07-02 22:24 ` Randy Brukardt
2014-07-06 20:40 ` MatthiasR
2014-07-07 0:25 ` Simon Clubley
2014-07-07 22:38 ` Randy Brukardt
2014-07-08 6:51 ` Simon Wright
2014-07-10 11:47 ` Simon Wright
2014-07-10 13:06 ` Simon Clubley
2014-07-11 18:05 ` Simon Wright
2014-07-11 20:22 ` Simon Clubley
2014-07-08 8:50 ` Brian Drummond
2014-07-08 12:12 ` Simon Clubley
2014-07-08 13:26 ` G.B.
2014-07-08 17:13 ` Simon Clubley
2014-07-08 15:36 ` Adam Beneschan
2014-07-08 15:40 ` Adam Beneschan
2014-07-08 20:34 ` Randy Brukardt
2014-07-09 7:31 ` Dmitry A. Kazakov
2014-07-10 0:11 ` Simon Clubley [this message]
2014-07-20 11:35 ` MatthiasR
2014-07-20 15:49 ` Simon Clubley
2014-07-26 11:05 ` MatthiasR
2014-08-10 11:20 ` MatthiasR
2014-07-01 12:03 ` Simon Clubley
2014-07-01 19:52 ` daniel.dmk
2014-07-01 20:40 ` Simon Clubley
2014-07-01 20:55 ` Simon Clubley
2014-07-01 21:01 ` Niklas Holsti
2014-07-01 21:20 ` Simon Clubley
2014-07-01 22:38 ` Niklas Holsti
2014-07-02 16:49 ` Simon Clubley
2014-07-01 21:55 ` daniel.dmk
2014-07-02 7:30 ` Simon Wright
2014-07-02 18:52 ` daniel.dmk
2014-07-04 23:51 ` Niklas Holsti
2014-07-05 0:18 ` Niklas Holsti
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