From: Dave Korn <dave.korn.cygwin@googlemail.com>
To: Joe Buck <Joe.Buck@synopsys.COM>
Cc: Jeff Law <law@redhat.com>,
Richard Guenther <richard.guenther@gmail.com>,
GCC <gcc@gcc.gnu.org>
Subject: Re: (known?) Issue with bitmap iterators
Date: Mon, 22 Jun 2009 19:07:00 -0000 [thread overview]
Message-ID: <4A3FD959.4060906@gmail.com> (raw)
In-Reply-To: <20090622174623.GA6603@synopsys.com>
Joe Buck wrote:
> As a general rule there is a performance cost for making iterators
> on a data structure safe with respect to modifications of that data
> structure. I'm not in a position to say what the right solution is
> in this case, but passes that iterate over bitmaps without modifying
> those bitmaps shouldn't be penalized. One solution sometimes used is
> two sets of iterators, with a slower version that's safe under
> modification.
But then we'll run into the same bug again when someone uses the wrong kind,
or changes the usage of a bitmap without changing which type it is. I think
making them all safe, but under --enable-checking only, with the safety code
compiled out when it's disabled might be a nice solution.
cheers,
DaveK
next prev parent reply other threads:[~2009-06-22 19:07 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-06-20 14:53 Jeff Law
2009-06-20 15:01 ` Richard Guenther
2009-06-21 3:27 ` Peter Bergner
2009-06-22 17:06 ` Jeff Law
2009-06-22 17:46 ` Joe Buck
2009-06-22 19:07 ` Dave Korn [this message]
2009-06-25 18:11 ` Daniel Berlin
2009-06-25 18:37 ` Jeff Law
2009-06-25 22:39 ` Dave Korn
2009-07-01 2:14 ` Jeff Law
2009-06-26 10:47 ` Alexander Monakov
2009-06-26 16:51 ` Joe Buck
2009-06-26 19:28 ` Alexander Monakov
2009-07-01 2:21 ` Jeff Law
2009-07-01 6:48 ` Dave Korn
2009-06-22 2:44 ` Daniel Berlin
2009-06-22 11:33 ` Dave Korn
2009-06-22 11:37 ` Richard Guenther
2009-06-22 13:06 ` Dave Korn
2009-06-22 13:38 ` Paolo Bonzini
2009-06-22 19:03 ` Dave Korn
2009-06-22 14:27 ` Andrew MacLeod
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