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From: "rguenther at suse dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/50904] [4.7 regression] pessimization when -fno-protect-parens is enabled by -Ofast
Date: Mon, 05 Dec 2011 09:57:00 -0000	[thread overview]
Message-ID: <bug-50904-4-2cCMdg4ZIK@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-50904-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50904

--- Comment #40 from rguenther at suse dot de <rguenther at suse dot de> 2011-12-05 09:55:47 UTC ---
On Mon, 5 Dec 2011, ebotcazou at gcc dot gnu.org wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50904
> 
> --- Comment #39 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2011-12-05 09:21:15 UTC ---
> > Thus, I think if at the RTL level we see a missed invariant motion then
> > this is a RTL level bug (esp. if it only triggers with  -fno-protect-parens).
> 
> Well, how can the RTL level invent load hoisting opportunities?  They are of
> course already present at the Tree level, see the .optimized dump:
> 
> vect_var_.124_350 = MEM[(real(kind=8)[9] *)&x2gauss];

They are considered dependent because they are still decomposed as

  vect_px2gauss.123_680 = &x2gauss;
...
  vect_var_.124_350 = MEM[(real(kind=8)[9] *)vect_px2gauss.123_680];

during LIM3.  Let me check why we don't fix that up in LIM dependence
checking.


  parent reply	other threads:[~2011-12-05  9:57 UTC|newest]

Thread overview: 51+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-28 17:19 [Bug rtl-optimization/50904] New: Induct benchmark of polyhedron slows down " venkataramanan.kumar.gnu at gmail dot com
2011-10-28 19:14 ` [Bug rtl-optimization/50904] " dominiq at lps dot ens.fr
2011-10-30  9:41 ` rguenth at gcc dot gnu.org
2011-10-30  9:41 ` rguenth at gcc dot gnu.org
2011-10-30 11:25 ` dominiq at lps dot ens.fr
2011-10-30 11:35 ` dominiq at lps dot ens.fr
2011-11-01 13:53 ` ebotcazou at gcc dot gnu.org
2011-11-02  5:51 ` venkataramanan.kumar.gnu at gmail dot com
2011-11-04 21:55 ` ebotcazou at gcc dot gnu.org
2011-11-05 11:54 ` [Bug rtl-optimization/50904] [4.7 regression] pessimization " rguenth at gcc dot gnu.org
2011-11-07  0:33 ` ebotcazou at gcc dot gnu.org
2011-11-08  0:43 ` ebotcazou at gcc dot gnu.org
2011-11-09  9:03 ` ebotcazou at gcc dot gnu.org
2011-11-09 10:40 ` venkataramanan.kumar.gnu at gmail dot com
2011-11-11 23:04 ` venkataramanan.kumar.gnu at gmail dot com
2011-11-12 17:22 ` [Bug tree-optimization/50904] " ebotcazou at gcc dot gnu.org
2011-11-19  7:18 ` venkataramanan.kumar.gnu at gmail dot com
2011-11-19  9:09 ` ebotcazou at gcc dot gnu.org
2011-12-01  8:51 ` rguenther at suse dot de
2011-12-01 19:53 ` [Bug rtl-optimization/50904] " ebotcazou at gcc dot gnu.org
2011-12-02  9:49 ` rguenther at suse dot de
2011-12-02 10:56 ` ebotcazou at gcc dot gnu.org
2011-12-02 11:51 ` rguenth at gcc dot gnu.org
2011-12-02 14:04 ` burnus at gcc dot gnu.org
2011-12-02 14:32 ` rguenther at suse dot de
2011-12-02 14:41 ` burnus at gcc dot gnu.org
2011-12-02 15:04 ` rguenther at suse dot de
2011-12-02 16:03 ` burnus at gcc dot gnu.org
2011-12-02 16:13 ` howarth at nitro dot med.uc.edu
2011-12-02 16:15 ` rguenther at suse dot de
2011-12-02 16:30 ` burnus at gcc dot gnu.org
2011-12-02 16:33 ` rguenther at suse dot de
2011-12-02 16:38 ` dominiq at lps dot ens.fr
2011-12-02 16:47 ` dominiq at lps dot ens.fr
2011-12-02 17:07 ` burnus at gcc dot gnu.org
2011-12-02 21:21 ` ebotcazou at gcc dot gnu.org
2011-12-03 14:55 ` dominiq at lps dot ens.fr
2011-12-05  8:19 ` rguenther at suse dot de
2011-12-05  8:27 ` rguenther at suse dot de
2011-12-05  9:21 ` ebotcazou at gcc dot gnu.org
2011-12-05  9:57 ` rguenther at suse dot de [this message]
2011-12-05 10:13 ` dominiq at lps dot ens.fr
2011-12-05 10:21 ` rguenth at gcc dot gnu.org
2011-12-05 10:28 ` [Bug tree-optimization/50904] " ebotcazou at gcc dot gnu.org
2011-12-05 11:13 ` rguenth at gcc dot gnu.org
2011-12-05 14:38 ` rguenth at gcc dot gnu.org
2011-12-05 14:40 ` rguenth at gcc dot gnu.org
2011-12-05 17:30 ` ebotcazou at gcc dot gnu.org
2011-12-05 17:59 ` dominiq at lps dot ens.fr
2011-12-06 10:00 ` venkataramanan.kumar.gnu at gmail dot com
2011-12-07 13:21 ` venkataramanan.kumar.gnu at gmail dot com

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