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From: "glisse at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/40073] Vector short/char shifts generate sub-optimal code
Date: Fri, 12 Jun 2015 12:01:00 -0000 [thread overview]
Message-ID: <bug-40073-4-mitT4cfg0j@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-40073-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=40073
Marc Glisse <glisse at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |law at gcc dot gnu.org
--- Comment #9 from Marc Glisse <glisse at gcc dot gnu.org> ---
(In reply to alalaw01 from comment #8)
> Is there a case where the result is different with vs without all the
> extending/truncating?
>
> It seems we should need the extending/truncating on vectors exactly iff we
> need it on scalars?
The extending/truncating is what the standard requires. Then we can start
optimizing (since indeed in many cases it isn't necessary), and Jeff is working
on exactly that (shortening). This seems like a rather straightforward case,
but who knows...
next prev parent reply other threads:[~2015-06-12 12:01 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <bug-40073-4@http.gcc.gnu.org/bugzilla/>
2014-04-26 7:00 ` glisse at gcc dot gnu.org
2015-06-12 9:56 ` alalaw01 at gcc dot gnu.org
2015-06-12 10:08 ` pinskia at gcc dot gnu.org
2015-06-12 11:39 ` alalaw01 at gcc dot gnu.org
2015-06-12 12:01 ` glisse at gcc dot gnu.org [this message]
2022-03-08 17:25 ` law at gcc dot gnu.org
2009-05-08 16:57 [Bug tree-optimization/40073] New: " meissner at linux dot vnet dot ibm dot com
2009-05-08 16:59 ` [Bug tree-optimization/40073] " meissner at linux dot vnet dot ibm dot com
2009-05-08 17:02 ` meissner at linux dot vnet dot ibm dot com
2009-05-08 17:03 ` meissner at linux dot vnet dot ibm dot com
2009-05-08 17:05 ` meissner at linux dot vnet dot ibm dot com
2009-05-08 17:06 ` meissner at linux dot vnet dot ibm dot com
2009-05-08 20:39 ` rguenth at gcc dot gnu dot org
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