From: "David S. Miller" <davem@redhat.com>
To: Werner.Almesberger@epfl.ch
Cc: adam@yggdrasil.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] removal of "static foo = 0"
Date: Mon, 27 Nov 2000 00:39:55 -0800 [thread overview]
Message-ID: <200011270839.AAA28672@pizda.ninka.net> (raw)
In-Reply-To: <20001127094139.H599@almesberger.net> (message from Werner Almesberger on Mon, 27 Nov 2000 09:41:39 +0100)
In-Reply-To: <200011270556.VAA12506@baldur.yggdrasil.com> <20001127094139.H599@almesberger.net>
Date: Mon, 27 Nov 2000 09:41:39 +0100
From: Werner Almesberger <Werner.Almesberger@epfl.ch>
egcs-2.91.66 indeed doesn't seem to make this optimization on i386.
(Maybe the pointer increment or pointer offset solution would
actually be slower - didn't check.) But I'm not sure if this is
also true for other versions/architectures, or other code
constructs.
There is no guarentee that contiguous data or bss section members
will appear contiguous and in the same order, in the final object.
In fact, a specific optimization done on MIPS and other platforms is
to place all data members under a certain size in a special
".small.data" section. So for example:
static int a;
static struct foo b;
static int b;
Would not place 'b' at "&a + sizeof(a) + sizeof(b)"
Also I believe linkers are allowed to arbitrarily reorder members in
the data and bss sections. I could be wrong on this one though.
Later,
David S. Miller
davem@redhat.com
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next prev parent reply other threads:[~2000-11-27 9:26 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2000-11-27 8:41 [PATCH] removal of "static foo = 0" Werner Almesberger
2000-11-27 5:56 ` Adam J. Richter
2000-11-27 8:39 ` David S. Miller [this message]
2000-11-27 9:08 ` Werner Almesberger
2000-11-27 17:21 ` Andrea Arcangeli
2000-11-27 17:36 ` Michael Meissner
2000-11-27 19:06 ` Andrea Arcangeli
2000-11-27 19:34 ` Richard B. Johnson
2000-11-28 0:28 ` Andrea Arcangeli
2000-11-28 11:25 ` Horst von Brand
2000-11-27 21:27 ` Marcus Sundberg
2000-11-28 0:49 ` real_root_dev Andries Brouwer
2000-11-28 3:10 ` [PATCH] removal of "static foo = 0" kumon
2000-11-28 3:28 ` Andrea Arcangeli
2000-11-28 3:35 ` Alexander Viro
2000-11-28 4:15 ` Michael Meissner
2000-11-28 9:55 ` Andreas Schwab
2000-11-28 15:16 ` Andrea Arcangeli
2000-11-28 16:09 ` Andreas Schwab
2000-11-28 19:29 ` Andrea Arcangeli
2000-11-28 16:44 ` Michael Meissner
2000-11-27 18:11 ` Richard B. Johnson
2000-11-27 18:01 ` Michael Meissner
-- strict thread matches above, loose matches on Subject: below --
2000-11-26 17:53 Elmer Joandi
2000-11-26 18:36 ` Alexander Viro
2000-11-26 19:11 ` Elmer Joandi
2000-11-26 22:49 ` Rogier Wolff
2000-11-26 15:15 Adam J. Richter
2000-11-25 20:19 Andries Brouwer
2000-11-25 21:07 ` Russell King
2000-11-25 21:29 ` Andries Brouwer
2000-11-26 1:19 ` Russell King
2000-11-25 22:11 ` Herbert Xu
2000-11-25 22:46 ` Andries Brouwer
2000-11-25 22:53 ` James A Sutherland
2000-11-25 23:55 ` Tim Waugh
2000-11-26 3:10 ` James A Sutherland
2000-11-26 10:37 ` Tigran Aivazian
2000-11-26 14:52 ` Philipp Rumpf
2000-11-28 0:01 ` Peter Samuelson
2000-11-27 4:00 ` Michael Meissner
2000-11-25 23:02 ` Jeff Garzik
2000-11-26 2:08 ` Andries Brouwer
2000-11-26 9:22 ` Martin Mares
2000-11-25 23:33 ` Herbert Xu
2000-11-27 10:03 ` Helge Hafting
2000-11-27 20:33 ` Albert D. Cahalan
2000-11-27 22:57 ` Russell King
2000-11-29 1:46 ` Albert D. Cahalan
2000-11-29 3:21 ` Peter Samuelson
2000-11-29 7:25 ` Russell King
2000-11-25 22:27 ` Tigran Aivazian
2000-11-26 1:32 ` Andries Brouwer
2000-11-26 6:21 ` Werner Almesberger
2000-11-26 2:11 ` Georg Nikodym
2000-11-26 4:25 ` Alan Cox
2000-11-26 5:01 ` John Alvord
2000-11-26 5:10 ` Andre Hedrick
2000-11-26 6:22 ` Keith Owens
2000-11-26 6:28 ` Andre Hedrick
2000-11-26 10:43 ` Tigran Aivazian
2000-11-26 10:52 ` Tigran Aivazian
2000-11-24 7:47 ` Pavel Machek
2000-11-26 14:32 ` bert hubert
2000-11-26 10:52 ` Rogier Wolff
2000-11-26 14:13 ` Philipp Rumpf
2000-11-26 20:47 ` H. Peter Anvin
2000-11-27 21:12 ` Kai Henningsen
2000-11-26 15:19 ` Georg Nikodym
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