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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug sanitizer/55309] gcc's address-sanitizer 66% slower than clang's
Date: Wed, 06 Feb 2013 12:49:00 -0000	[thread overview]
Message-ID: <bug-55309-4-Jl5T4pFReJ@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-55309-4@http.gcc.gnu.org/bugzilla/>


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55309

--- Comment #21 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-02-06 12:48:39 UTC ---
As the shadow memory doesn't have information about what locations are
read-only, it only has info whether the relevant bytes are valid, or invalid
(or some invalid, some valid), and for all invalid a few magic values for more
detailed reporting.  So, if you have a RMW statement, without any asan
optimization it will first check the read, and already fail on the read, so
even with the optimization if you just check the read and not the write, the
user visible behavior will be exactly the same.


  parent reply	other threads:[~2013-02-06 12:49 UTC|newest]

Thread overview: 59+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-11-13 10:01 [Bug other/55309] New: " markus at trippelsdorf dot de
2012-11-13 21:10 ` [Bug other/55309] " konstantin.s.serebryany at gmail dot com
2012-11-13 21:31 ` markus at trippelsdorf dot de
2012-11-14  7:52 ` jakub at gcc dot gnu.org
2012-11-14 16:38 ` jakub at gcc dot gnu.org
2012-11-14 17:03 ` markus at trippelsdorf dot de
2013-02-05  9:22 ` [Bug sanitizer/55309] " kcc at gcc dot gnu.org
2013-02-05  9:43 ` kcc at gcc dot gnu.org
2013-02-05  9:56 ` jakub at gcc dot gnu.org
2013-02-05 10:31 ` kcc at gcc dot gnu.org
2013-02-05 10:42 ` kcc at gcc dot gnu.org
2013-02-05 10:55 ` jakub at gcc dot gnu.org
2013-02-05 11:18 ` markus at trippelsdorf dot de
2013-02-05 11:24 ` jakub at gcc dot gnu.org
2013-02-05 11:26 ` jakub at gcc dot gnu.org
2013-02-05 12:23 ` kcc at gcc dot gnu.org
2013-02-06 10:56 ` dodji at gcc dot gnu.org
2013-02-06 11:19 ` kcc at gcc dot gnu.org
2013-02-06 12:25 ` kcc at gcc dot gnu.org
2013-02-06 12:39 ` rguenth at gcc dot gnu.org
2013-02-06 12:43 ` kcc at gcc dot gnu.org
2013-02-06 12:49 ` jakub at gcc dot gnu.org [this message]
2013-02-06 15:03 ` dodji at gcc dot gnu.org
2013-02-07  5:02 ` kcc at gcc dot gnu.org
2013-02-07 17:01 ` jakub at gcc dot gnu.org
2013-02-07 17:18 ` dvyukov at google dot com
2013-02-08  6:31 ` kcc at gcc dot gnu.org
2013-02-08  9:02 ` jakub at gcc dot gnu.org
2013-02-08  9:13 ` kcc at gcc dot gnu.org
2013-02-08  9:25 ` jakub at gcc dot gnu.org
2013-02-11 14:43 ` kcc at gcc dot gnu.org
2013-02-11 15:03 ` jakub at gcc dot gnu.org
2013-02-12  6:48 ` kcc at gcc dot gnu.org
2013-02-12  7:03 ` kcc at gcc dot gnu.org
2013-02-12  8:40 ` jakub at gcc dot gnu.org
2013-02-12  8:47 ` dvyukov at google dot com
2013-02-12  8:59 ` kcc at gcc dot gnu.org
2013-02-12 11:18 ` kcc at gcc dot gnu.org
2013-02-12 11:31 ` kcc at gcc dot gnu.org
2013-02-12 11:42 ` jakub at gcc dot gnu.org
2013-02-12 14:00 ` howarth at nitro dot med.uc.edu
2013-02-12 14:12 ` jakub at gcc dot gnu.org
2013-02-12 14:42 ` howarth at nitro dot med.uc.edu
2013-02-22  7:11 ` kcc at gcc dot gnu.org
2013-02-22  8:31 ` Joost.VandeVondele at mat dot ethz.ch
2013-02-22  8:36 ` kcc at gcc dot gnu.org
2013-02-22 13:09 ` jakub at gcc dot gnu.org
2013-02-22 13:52 ` kcc at gcc dot gnu.org
2013-02-22 13:55 ` Joost.VandeVondele at mat dot ethz.ch
2013-02-22 14:30 ` kcc at gcc dot gnu.org
2013-02-22 14:54 ` kcc at gcc dot gnu.org
2013-02-22 15:01 ` jakub at gcc dot gnu.org
2013-02-22 15:04 ` jakub at gcc dot gnu.org
2013-02-22 15:06 ` kcc at gcc dot gnu.org
2013-02-22 15:14 ` jakub at gcc dot gnu.org
2013-02-22 16:11 ` joseph at codesourcery dot com
2013-02-26  7:43 ` kcc at gcc dot gnu.org
2013-02-28 11:32 ` kcc at gcc dot gnu.org
2014-01-27  8:22 ` trippels at gcc dot gnu.org

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