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From: "rguenther at suse dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/108322] Using __restrict parameter with -ftree-vectorize (default with -O2) results in massive code bloat
Date: Tue, 10 Jan 2023 09:09:30 +0000	[thread overview]
Message-ID: <bug-108322-4-TuQAh73Zm0@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-108322-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108322

--- Comment #6 from rguenther at suse dot de <rguenther at suse dot de> ---
On Tue, 10 Jan 2023, amonakov at gcc dot gnu.org wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108322
> 
> --- Comment #5 from Alexander Monakov <amonakov at gcc dot gnu.org> ---
> (In reply to Richard Biener from comment #4)
> > 
> > For the case at hand loading two vectors from the destination and then
> > punpck{h,l}bw and storing them again might be the most efficient thing
> > to do here.
> 
> I think such read-modify-write on the destination introduces a data race for
> bytes that are not accessed in the original program, so that would be okay only
> under -fallow-store-data-races?

Yes, obviously.

      parent reply	other threads:[~2023-01-10  9:09 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-06 23:27 [Bug tree-optimization/108322] New: Using __register " gerbilsoft at gerbilsoft dot com
2023-01-06 23:28 ` [Bug tree-optimization/108322] " gerbilsoft at gerbilsoft dot com
2023-01-06 23:35 ` [Bug target/108322] Using __restrict " pinskia at gcc dot gnu.org
2023-01-07  7:30 ` amonakov at gcc dot gnu.org
2023-01-10  7:58 ` rguenth at gcc dot gnu.org
2023-01-10  8:02 ` amonakov at gcc dot gnu.org
2023-01-10  9:09 ` rguenther at suse dot de [this message]

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