From: Jeffrey A Law <law@cygnus.com>
To: richard.earnshaw@arm.com
Cc: Mark Mitchell <mark@codesourcery.com>,
rms@gnu.org, jbuck@synopsys.com, mrs@wrs.com, gcc@gcc.gnu.org
Subject: Re: type based aliasing again
Date: Thu, 30 Sep 1999 18:02:00 -0000 [thread overview]
Message-ID: <2859.937221516@upchuck.cygnus.com> (raw)
Message-ID: <19990930180200.cjDX-_7ZPsmbzOmH7zS8dntTN_ouJynXhfbl9g6oGkk@z> (raw)
In-Reply-To: <199909131102.MAA25960@sun52.NIS.cambridge>
In message < 199909131102.MAA25960@sun52.NIS.cambridge >you write:
>
> mark@codesourcery.com said:
> > I think that making -fno-strict-aliasing the default is sensible
> > proposal, and worth debating.
>
>
> It is the default at -O1 or less. I would be inclined to argue that this
> should be adequate for "legacy" code and that the higher levels of
> optimization should be allowed to fully exploit the provisions of the C
> standard (this is not to suggest that a warning shouldn't be generated if
> possible).
Good point.
> We are somewhat constrained by our relatively limited number of
> optimization levels (0, 1, 2, 3, s); I guess extending the range is hard,
> mainly because of a user-education issue. But it would be useful if we
> could have a level above which we say that we assume that code fully
> conforms to the C (or other relevant) standard.
We really need to make some space in the -O namespace. So we shouldn't let
that problem stop us if people think it's a reasonable thing to do.
Right now -O3 is just -O2 + -finline-functions.
I've got no objection to moving -finline-functions to some higher -O level to
give us some room to add optimizations which may depend on strict adherence of
code to the ANSI/ISO standards or which may take more memory/time (load/store
motion would be a good example).
Yes there's a user education issue, but it's a hell of a lot smaller than the
"how to write conforming code" education issue.
jeff
next prev parent reply other threads:[~1999-09-30 18:02 UTC|newest]
Thread overview: 408+ messages / expand[flat|nested] mbox.gz Atom feed top
1999-09-08 19:13 Mike Stump
1999-09-08 19:31 ` Joe Buck
1999-09-30 18:02 ` Joe Buck
1999-09-09 7:12 ` Marc Espie
1999-09-09 20:35 ` Jeffrey A Law
1999-09-10 12:29 ` Sudish Joseph
1999-09-30 18:02 ` Sudish Joseph
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Marc Espie
1999-09-09 23:25 ` Richard Stallman
1999-09-08 18:11 ` Joe Buck
1999-09-08 18:43 ` Mark Mitchell
1999-09-08 19:25 ` Joe Buck
1999-09-08 19:51 ` David Edelsohn
1999-09-30 18:02 ` David Edelsohn
1999-09-30 18:02 ` Joe Buck
1999-09-08 19:44 ` Joe Buck
1999-09-08 20:26 ` Mark Mitchell
1999-09-08 20:43 ` Joe Buck
1999-09-08 21:45 ` Mark Mitchell
1999-09-08 22:04 ` Joe Buck
1999-09-08 22:25 ` Mark Mitchell
1999-09-30 18:02 ` Mark Mitchell
1999-09-09 2:08 ` Jeffrey A Law
1999-09-09 10:51 ` Joe Buck
1999-09-09 16:51 ` John Vickers
1999-09-09 17:04 ` Joe Buck
1999-09-09 17:12 ` John Vickers
1999-09-30 18:02 ` John Vickers
1999-09-30 18:02 ` Joe Buck
1999-09-30 18:02 ` John Vickers
1999-09-15 2:07 ` Jeffrey A Law
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Joe Buck
1999-09-09 23:26 ` Richard Stallman
1999-09-09 23:38 ` Jeffrey A Law
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Richard Stallman
1999-09-09 23:26 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Jeffrey A Law
1999-09-09 23:25 ` Richard Stallman
1999-09-10 0:06 ` Mark Mitchell
1999-09-10 0:13 ` Joe Buck
1999-09-30 18:02 ` Joe Buck
1999-09-11 0:17 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Mark Mitchell
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Joe Buck
1999-09-08 23:20 ` Richard Henderson
1999-09-08 23:41 ` Mark Mitchell
1999-09-08 23:44 ` Richard Henderson
1999-09-08 23:51 ` Mark Mitchell
1999-09-30 18:02 ` Mark Mitchell
1999-09-09 2:45 ` Jeffrey A Law
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Richard Henderson
1999-09-30 18:02 ` Mark Mitchell
1999-09-30 18:02 ` Richard Henderson
1999-09-30 18:02 ` Mark Mitchell
1999-09-30 18:02 ` Joe Buck
1999-09-08 21:33 ` Joe Buck
1999-09-08 21:56 ` Mark Mitchell
1999-09-30 18:02 ` Mark Mitchell
1999-09-09 1:38 ` Martin v. Loewis
1999-09-30 18:02 ` Martin v. Loewis
1999-09-09 23:25 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Joe Buck
1999-09-09 2:20 ` Jeffrey A Law
1999-09-09 7:58 ` craig
1999-09-09 10:36 ` Joe Buck
1999-09-09 10:55 ` Mark Mitchell
1999-09-11 0:15 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Mark Mitchell
1999-09-09 11:51 ` craig
1999-09-09 12:45 ` Joe Buck
1999-09-30 18:02 ` Joe Buck
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Joe Buck
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Jeffrey A Law
1999-09-09 23:26 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Mark Mitchell
1999-09-30 18:02 ` Joe Buck
1999-09-09 23:25 ` Richard Stallman
1999-09-10 0:03 ` Mark Mitchell
1999-09-10 0:23 ` Joe Buck
1999-09-11 0:17 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Joe Buck
1999-09-11 0:17 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Mark Mitchell
1999-09-10 14:29 ` Marc Lehmann
1999-09-30 18:02 ` Marc Lehmann
1999-09-15 2:05 ` Jeffrey A Law
1999-09-15 7:55 ` Nick Ing-Simmons
1999-09-30 18:02 ` Nick Ing-Simmons
1999-09-15 23:14 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Mark Mitchell
1999-09-08 20:44 ` Joe Buck
1999-09-30 18:02 ` Joe Buck
1999-09-14 3:04 ` Alexandre Oliva
1999-09-14 5:34 ` Bernd Schmidt
1999-09-14 5:45 ` Alexandre Oliva
1999-09-14 5:52 ` Bernd Schmidt
1999-09-30 18:02 ` Bernd Schmidt
1999-09-21 1:16 ` Rask Ingemann Lambertsen
1999-09-21 2:02 ` Jamie Lokier
1999-09-30 18:02 ` Jamie Lokier
1999-09-30 18:02 ` Rask Ingemann Lambertsen
1999-09-30 18:02 ` Alexandre Oliva
1999-09-14 9:31 ` Andi Kleen
1999-09-30 18:02 ` Andi Kleen
1999-09-30 18:02 ` Bernd Schmidt
1999-09-14 22:22 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Alexandre Oliva
1999-09-30 18:02 ` Joe Buck
1999-09-10 0:11 ` Joe Buck
1999-09-10 8:43 ` craig
1999-09-10 18:25 ` Jonathan Larmour
1999-09-11 3:50 ` craig
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Jonathan Larmour
1999-09-11 0:15 ` Richard Stallman
1999-09-11 3:51 ` craig
1999-09-12 0:51 ` Richard Stallman
1999-09-12 8:54 ` craig
1999-09-13 0:47 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` craig
1999-09-11 0:14 ` Richard Stallman
1999-09-11 15:20 ` Mark Mitchell
1999-09-11 18:04 ` David Edelsohn
1999-09-11 18:20 ` Mark Mitchell
1999-09-11 23:40 ` Sudish Joseph
1999-09-30 18:02 ` Sudish Joseph
1999-09-12 8:16 ` Robert Lipe
1999-09-30 18:02 ` Robert Lipe
1999-09-30 18:02 ` Mark Mitchell
1999-09-13 0:47 ` Richard Stallman
1999-09-15 2:06 ` Jeffrey A Law
1999-09-15 8:02 ` Nick Ing-Simmons
1999-09-15 9:20 ` Jeffrey A Law
1999-09-15 9:31 ` David Edelsohn
1999-09-15 10:02 ` craig
1999-09-16 23:13 ` Richard Stallman
1999-09-17 1:51 ` craig
1999-09-17 22:16 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` David Edelsohn
1999-09-15 9:56 ` Nick Ing-Simmons
1999-09-15 10:08 ` craig
1999-09-15 10:48 ` Nick Ing-Simmons
1999-09-15 14:32 ` craig
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Nick Ing-Simmons
1999-09-16 10:54 ` Andi Kleen
1999-09-16 12:08 ` Joern Rennecke
1999-09-16 12:18 ` Mark Mitchell
1999-09-17 7:07 ` __typealias qualifier (was Re: type based aliasing again) patl
1999-09-17 8:32 ` Mark Mitchell
1999-09-30 18:02 ` Mark Mitchell
1999-09-30 18:02 ` Patrick J. LoPresti
1999-09-30 18:02 ` type based aliasing again Mark Mitchell
1999-09-30 18:02 ` Joern Rennecke
1999-09-16 14:29 ` craig
1999-09-16 22:19 ` Andi Kleen
1999-09-30 18:02 ` Andi Kleen
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Andi Kleen
1999-09-16 23:13 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Nick Ing-Simmons
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Nick Ing-Simmons
1999-09-15 23:14 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` David Edelsohn
1999-09-12 9:45 ` Jonathan Larmour
1999-09-30 18:02 ` Jonathan Larmour
1999-09-13 0:47 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-13 4:05 ` Richard Earnshaw
1999-09-15 2:05 ` Jeffrey A Law [this message]
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Richard Earnshaw
1999-09-30 18:02 ` Mark Mitchell
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Joe Buck
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Mike Stump
1999-09-09 14:26 Mike Stump
1999-09-09 14:38 ` Mark Mitchell
1999-09-11 0:16 ` Richard Stallman
1999-09-15 2:07 ` Jeffrey A Law
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Mark Mitchell
1999-09-30 18:02 ` Mike Stump
1999-09-09 15:40 Claus Fischer
1999-09-09 15:57 ` David Starner
1999-09-09 16:24 ` Claus Fischer
1999-09-09 16:55 ` Joe Buck
1999-09-09 17:31 ` Claus Fischer
1999-09-30 18:02 ` Claus Fischer
1999-09-30 18:02 ` Joe Buck
1999-09-10 8:42 ` craig
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Claus Fischer
1999-09-30 18:02 ` David Starner
1999-09-09 16:37 ` Jeffrey A Law
1999-09-09 17:15 ` Claus Fischer
1999-09-30 18:02 ` Claus Fischer
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Claus Fischer
1999-09-09 21:54 Alex Rosenberg
1999-09-30 18:02 ` Alex Rosenberg
1999-09-10 8:43 craig
1999-09-12 0:49 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` craig
1999-09-11 18:21 Phil Edwards
1999-09-30 18:02 ` Phil Edwards
1999-09-11 21:48 N8TM
1999-09-30 18:02 ` N8TM
[not found] <9377.936981585@upchuck.cygnus.com>
1999-09-12 0:52 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-12 11:20 Josh Stern
1999-09-30 18:02 ` Josh Stern
1999-09-13 10:55 R. Kelley Cook
1999-09-13 13:22 ` craig
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` R. Kelley Cook
1999-09-13 16:34 Mike Stump
1999-09-14 22:20 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Mike Stump
1999-09-13 21:45 N8TM
1999-09-14 4:01 ` Marc Espie
1999-09-14 9:56 ` David Edelsohn
1999-09-14 10:10 ` Richard Earnshaw
1999-09-14 10:31 ` Nick Ing-Simmons
1999-09-14 10:52 ` David Edelsohn
1999-09-14 11:11 ` craig
1999-09-14 14:44 ` David Edelsohn
1999-09-30 18:02 ` David Edelsohn
1999-09-14 15:06 ` David Edelsohn
1999-09-14 17:35 ` Marc Lehmann
1999-09-30 18:02 ` Marc Lehmann
1999-09-14 23:41 ` craig
1999-09-15 8:28 ` Marc Lehmann
1999-09-30 18:02 ` Marc Lehmann
1999-09-15 9:19 ` David Edelsohn
1999-09-15 9:59 ` Nick Ing-Simmons
1999-09-15 15:33 ` David Edelsohn
1999-09-30 18:02 ` David Edelsohn
1999-09-30 18:02 ` Nick Ing-Simmons
1999-09-15 10:01 ` craig
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` David Edelsohn
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` David Edelsohn
1999-09-30 18:02 ` craig
1999-09-14 11:58 ` Gerald Pfeifer
1999-09-30 18:02 ` Gerald Pfeifer
1999-09-30 18:02 ` David Edelsohn
1999-09-14 11:01 ` craig
1999-09-14 11:14 ` craig
1999-09-30 18:02 ` craig
1999-09-14 11:39 ` Mark Mitchell
1999-09-14 14:48 ` Toon Moene
1999-09-14 15:00 ` David Edelsohn
1999-09-14 16:01 ` Toon Moene
1999-09-14 16:15 ` David Edelsohn
1999-09-14 16:43 ` Mark Mitchell
1999-09-30 18:02 ` Mark Mitchell
1999-09-14 17:39 ` Marc Lehmann
1999-09-30 18:02 ` Marc Lehmann
1999-09-30 18:02 ` David Edelsohn
1999-09-14 16:19 ` dvv
1999-09-14 17:38 ` Michael Meissner
1999-09-30 18:02 ` Michael Meissner
1999-09-30 18:02 ` Dima Volodin
1999-09-30 18:02 ` Toon Moene
1999-09-30 18:02 ` David Edelsohn
1999-09-14 15:08 ` Mark Mitchell
1999-09-30 18:02 ` Mark Mitchell
1999-09-30 18:02 ` Toon Moene
1999-09-30 18:02 ` Mark Mitchell
1999-09-30 18:02 ` craig
1999-09-14 23:46 ` Geoff Keating
1999-09-15 7:47 ` Nick Ing-Simmons
1999-09-30 18:02 ` Nick Ing-Simmons
1999-09-30 18:02 ` Geoff Keating
1999-09-30 18:02 ` Nick Ing-Simmons
1999-09-30 18:02 ` Richard Earnshaw
1999-09-14 17:22 ` Marc Lehmann
1999-09-30 18:02 ` Marc Lehmann
1999-09-30 18:02 ` David Edelsohn
1999-09-14 17:23 ` Marc Lehmann
1999-09-15 1:59 ` Marc Espie
1999-09-15 8:28 ` Marc Lehmann
1999-09-30 18:02 ` Marc Lehmann
1999-09-30 18:02 ` Marc Espie
1999-09-30 18:02 ` Marc Lehmann
1999-09-15 2:01 ` Jeffrey A Law
1999-09-30 18:02 ` Jeffrey A Law
1999-09-30 18:02 ` Marc Espie
1999-09-30 18:02 ` N8TM
1999-09-14 6:46 Marcel Cox
1999-09-14 6:50 ` Bernd Schmidt
1999-09-14 7:14 ` Marcel Cox
1999-09-14 8:45 ` Jamie Lokier
1999-09-30 18:02 ` Jamie Lokier
1999-09-30 18:02 ` Marcel Cox
1999-09-30 18:02 ` Bernd Schmidt
1999-09-30 18:02 ` Marcel Cox
1999-09-15 7:02 David Ronis
1999-09-30 18:02 ` David Ronis
1999-09-15 8:27 Kaveh R. Ghazi
1999-09-15 8:57 ` Nathan Sidwell
1999-09-30 18:02 ` Nathan Sidwell
1999-09-30 18:02 ` Kaveh R. Ghazi
1999-09-15 11:42 Michael J. Bedy
1999-09-15 14:32 ` craig
1999-09-16 23:14 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Michael J. Bedy
1999-09-15 21:47 Florin Mateoc
1999-09-16 2:18 ` craig
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` Florin Mateoc
[not found] <Pine.SO4.4.05.9909160153420.23533-100000@tamarack.cs.mtu.edu>
1999-09-16 2:19 ` craig
1999-09-30 18:02 ` craig
1999-09-16 6:12 Artem Hodyush
1999-09-16 23:15 ` Richard Stallman
1999-09-16 23:38 ` Gabriel Dos_Reis
1999-09-17 22:16 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Gabriel Dos_Reis
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Artem Hodyush
[not found] <199909161750.LAA12073@basho.fc.hp.com>
1999-09-16 14:29 ` craig
1999-09-20 15:17 ` John W. Stevens
1999-09-30 18:02 ` John W. Stevens
1999-09-30 18:02 ` craig
1999-09-17 9:02 Harvey J. Stein
1999-09-30 18:02 ` Harvey J. Stein
1999-09-18 2:51 Ross Morgan-Linial
[not found] ` <19990918151905.F1650@cerebro.laendle>
1999-09-18 22:18 ` Ross Morgan-Linial
1999-09-30 18:02 ` Ross Morgan-Linial
1999-09-30 18:02 ` Ross Morgan-Linial
1999-09-18 3:25 Artem Hodyush
1999-09-18 11:29 ` Russ Allbery
1999-09-20 5:54 ` Joern Rennecke
1999-09-30 18:02 ` Joern Rennecke
1999-09-30 18:02 ` Russ Allbery
1999-09-19 13:54 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-21 8:50 ` Harvey J. Stein
1999-09-30 18:02 ` Harvey J. Stein
1999-09-30 18:02 ` Artem Hodyush
1999-09-18 7:30 Stephen L Moshier
1999-09-30 18:02 ` Stephen L Moshier
1999-09-18 8:33 N8TM
1999-09-30 18:02 ` N8TM
1999-09-21 8:48 Harvey J. Stein
1999-09-22 12:15 ` Richard Stallman
1999-09-22 13:08 ` Harvey J. Stein
1999-09-24 23:37 ` Richard Stallman
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Harvey J. Stein
1999-09-30 18:02 ` Richard Stallman
1999-09-30 18:02 ` Harvey J. Stein
[not found] <19990921182843.25292.qmail@deer>
1999-09-21 15:47 ` John W. Stevens
1999-09-21 16:15 ` craig
1999-09-21 20:37 ` David Edelsohn
1999-09-30 18:02 ` David Edelsohn
1999-09-23 9:06 ` John W. Stevens
1999-09-23 11:06 ` craig
1999-09-30 18:02 ` craig
1999-09-30 18:02 ` John W. Stevens
1999-09-30 18:02 ` craig
1999-09-27 6:56 ` Rask Ingemann Lambertsen
1999-09-27 8:32 ` Joe Buck
1999-09-30 18:02 ` Joe Buck
1999-09-30 18:02 ` Rask Ingemann Lambertsen
1999-09-30 18:02 ` John W. Stevens
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