public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
From: "rguenther at suse dot de" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/37021] Fortran Complex reduction / multiplication not vectorized Date: Sun, 25 Jan 2009 11:04:00 -0000 [thread overview] Message-ID: <20090125110423.4239.qmail@sourceware.org> (raw) In-Reply-To: <bug-37021-10053@http.gcc.gnu.org/bugzilla/> ------- Comment #7 from rguenther at suse dot de 2009-01-25 11:04 ------- Subject: Re: Fortran Complex reduction / multiplication not vectorized On Sun, 25 Jan 2009, irar at il dot ibm dot com wrote: > > > ------- Comment #6 from irar at il dot ibm dot com 2009-01-25 09:12 ------- > (In reply to comment #5) > > So, > > 4) The vectorized version sucks because we have to use peeling for niters > > because we need to unroll the loop once and cannot apply SLP here. > > What do you mean by "unroll the loop once"? The vectorization factor is two, so we need two copies of the loop body (which means unrolling it once and creating an epilogue loop because niter may be odd) > > Q1: does SLP work with reductions at all? > > No. SLP currently originates from groups of strided stores. Ah, I see. In this loop we have two reductions, so to apply SLP we would need to see that we can use a group of reductions for SLP? > > Q2: does SLP do pattern recognition? > > Pattern recoginition is done before SLP, and SLP handles stmts that were marked > as a part of a pattern. There is no SLP specific pattern recoginition. Ok, but with a reduction it won't help me here. Can a loop be vectorized with just pattern recognition? Hm, if I remember correctly we detect scalar patterns and then vectorize them. We don't support detecting "vector patterns" from scalar code, correct? Thanks, Richard. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37021
next prev parent reply other threads:[~2009-01-25 11:04 UTC|newest] Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top 2008-08-04 17:57 [Bug tree-optimization/37021] New: " rguenth at gcc dot gnu dot org 2008-08-04 17:59 ` [Bug tree-optimization/37021] " rguenth at gcc dot gnu dot org 2008-08-19 15:31 ` rguenth at gcc dot gnu dot org 2009-01-21 15:43 ` rguenth at gcc dot gnu dot org 2009-01-23 15:33 ` rguenth at gcc dot gnu dot org 2009-01-23 15:36 ` rguenth at gcc dot gnu dot org 2009-01-25 9:13 ` irar at il dot ibm dot com 2009-01-25 11:04 ` rguenther at suse dot de [this message] 2009-01-25 12:17 ` irar at il dot ibm dot com 2009-01-27 12:40 ` dorit at gcc dot gnu dot org [not found] <bug-37021-4@http.gcc.gnu.org/bugzilla/> 2011-03-25 11:49 ` sebastian.hegler@tu-dresden.de 2011-03-25 12:27 ` sebastian.hegler@tu-dresden.de 2011-03-25 13:13 ` rguenther at suse dot de 2012-07-13 8:46 ` rguenth at gcc dot gnu.org 2013-02-13 15:58 ` rguenth at gcc dot gnu.org 2013-03-27 10:39 ` rguenth at gcc dot gnu.org 2013-03-27 10:40 ` rguenth at gcc dot gnu.org 2013-04-07 13:18 ` dominiq at lps dot ens.fr 2015-05-12 11:56 ` rguenth at gcc dot gnu.org 2015-06-10 10:45 ` rguenth at gcc dot gnu.org 2015-08-25 8:11 ` rguenth at gcc dot gnu.org 2015-08-27 22:09 ` wschmidt at gcc dot gnu.org 2015-08-28 7:46 ` rguenther at suse dot de 2015-08-28 13:20 ` wschmidt at gcc dot gnu.org 2015-08-28 13:31 ` wschmidt at gcc dot gnu.org 2015-10-22 10:03 ` rguenth at gcc dot gnu.org 2023-07-21 12:28 ` rguenth at gcc dot gnu.org
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20090125110423.4239.qmail@sourceware.org \ --to=gcc-bugzilla@gcc.gnu.org \ --cc=gcc-bugs@gcc.gnu.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).