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From: Marek Polacek <polacek@redhat.com>
To: Jakub Jelinek <jakub@redhat.com>
Cc: ramrad01@arm.com, Richard Biener <rguenther@suse.de>,
	       Dodji Seketeli <dseketel@redhat.com>,
	       Konstantin Serebryany <konstantin.s.serebryany@gmail.com>,
	       Tobias Burnus <burnus@net-b.de>,
	gcc-patches <gcc-patches@gcc.gnu.org>,
	       Richard Sandiford <rdsandiford@googlemail.com>
Subject: Re: [PATCH] Add support for -fno-sanitize-recover and -fsanitize-undefined-trap-on-error (PR sanitizer/60275)
Date: Thu, 15 May 2014 15:22:00 -0000	[thread overview]
Message-ID: <20140515152151.GE8173@redhat.com> (raw)
In-Reply-To: <20140515151600.GO10386@tucnak.redhat.com>

On Thu, May 15, 2014 at 05:16:00PM +0200, Jakub Jelinek wrote:
> On Thu, May 15, 2014 at 05:08:10PM +0200, Marek Polacek wrote:
> > On Thu, May 15, 2014 at 11:39:26AM +0100, Ramana Radhakrishnan wrote:
> > > What's the overhead with bootstrap-ubsan ?
> > 
> > I timed normal bootstrap and bootstrap-ubsan on x86_64, 24 cores,
> > Intel(R) Xeon(R) CPU X5670  @ 2.93GHz (aka cfarm 20) and the results:
> > 
> > --enable-languages=all
> > 
> > real	35m10.419s
> > user	204m5.613s
> > sys	6m15.615s
> > 
> > --enable-languages=all --with-build-config=bootstrap-ubsan
> > 
> > real	71m39.338s
> > user	347m53.409s
> > sys	7m44.281s
> 
> Note that doesn't mean -fsanitize=undefined generated code is twice as slow
> as code compiled without it, guess most of the extra overhead is actually
> compile time (mostly larger cfg due to all the extra checks).

And I think the main offender will be the NULL checking with its extra bbs.  So to
alleviate the cfg size one can use -fsanitize=undefined -fno-sanitize=null - I'd
expect this to make a significant difference.  

	Marek

  reply	other threads:[~2014-05-15 15:22 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-04-15 10:12 Jakub Jelinek
2014-04-23  8:14 ` Richard Biener
2014-05-15 10:30 ` Richard Sandiford
2014-05-15 10:34   ` Jakub Jelinek
2014-05-15 10:38     ` Marek Polacek
2014-05-15 12:42       ` Richard Sandiford
2014-05-15 12:47         ` Marek Polacek
2014-05-15 13:01           ` Richard Biener
2014-05-15 10:39     ` Ramana Radhakrishnan
2014-05-15 15:08       ` Marek Polacek
2014-05-15 15:16         ` Jakub Jelinek
2014-05-15 15:22           ` Marek Polacek [this message]
2014-05-15 18:32         ` Toon Moene
2014-05-15 18:37           ` Marek Polacek
2014-05-15 19:11             ` Jakub Jelinek
2014-05-15 19:20               ` Toon Moene
2014-05-15 19:27               ` Marek Polacek

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