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 testsuite/63175] [4.9/5 regression] FAIL: gcc.dg/vect/costmodel/ppc/costmodel-bb-slp-9a.c scan-tree-dump-times slp2" basic block vectorized using SLP" 1
Date: Wed, 04 Mar 2015 13:55:00 -0000	[thread overview]
Message-ID: <bug-63175-4-Q0XmIcK5nr@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-63175-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63175

--- Comment #33 from rguenther at suse dot de <rguenther at suse dot de> ---
On Wed, 4 Mar 2015, dje at gcc dot gnu.org wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63175
> 
> --- Comment #32 from David Edelsohn <dje at gcc dot gnu.org> ---
> "So currently on a tie we don't vectorize basic-blocks (same with GCC 4.8).
> That's kind of arbitrary, but given instruction encoding size on x86 for
> example
> it makes sense."

That was just a random comment and not the design decision for that code.
If costs are near tie then it becomes quite arbitrary given the very very
simple cost modeling of the scalar code.

That we choose to keep the scalar code in case the cost model says its
equally expensive than the vectorized code is an arbitrary choice.

I wonder if in this particular case the vectorized or the scalar version
is faster (on ppc)?


  parent reply	other threads:[~2015-03-04 13:55 UTC|newest]

Thread overview: 39+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-63175-4@http.gcc.gnu.org/bugzilla/>
2014-09-05  8:47 ` rguenth at gcc dot gnu.org
2014-10-30 10:42 ` jakub at gcc dot gnu.org
2014-11-24 13:16 ` rguenth at gcc dot gnu.org
2015-02-21 20:07 ` msebor at gcc dot gnu.org
2015-02-22 20:38 ` macro@linux-mips.org
2015-02-24  6:56 ` msebor at gcc dot gnu.org
2015-02-25 20:45 ` msebor at gcc dot gnu.org
2015-02-26 10:19 ` rguenth at gcc dot gnu.org
2015-02-26 10:56 ` rguenth at gcc dot gnu.org
2015-02-27  9:18 ` rguenth at gcc dot gnu.org
2015-02-27  9:49 ` rguenth at gcc dot gnu.org
2015-02-27 11:23 ` rguenth at gcc dot gnu.org
2015-02-27 11:24 ` rguenth at gcc dot gnu.org
2015-02-28  9:26 ` msebor at gcc dot gnu.org
2015-03-02 14:14 ` rguenth at gcc dot gnu.org
2015-03-02 14:24 ` rguenth at gcc dot gnu.org
2015-03-02 16:24 ` msebor at gcc dot gnu.org
2015-03-02 16:48 ` rguenther at suse dot de
2015-03-02 16:50 ` rguenther at suse dot de
2015-03-02 16:58 ` msebor at gcc dot gnu.org
2015-03-02 17:47 ` rguenther at suse dot de
2015-03-02 18:13 ` msebor at gcc dot gnu.org
2015-03-02 18:23 ` rguenther at suse dot de
2015-03-03  5:10 ` msebor at gcc dot gnu.org
2015-03-03  9:21 ` rguenther at suse dot de
2015-03-03  9:42 ` rguenth at gcc dot gnu.org
2015-03-03 15:05 ` dje at gcc dot gnu.org
2015-03-03 16:19 ` wschmidt at gcc dot gnu.org
2015-03-03 16:22 ` wschmidt at gcc dot gnu.org
2015-03-04  1:15 ` msebor at gcc dot gnu.org
2015-03-04  9:17 ` rguenth at gcc dot gnu.org
2015-03-04 13:42 ` dje at gcc dot gnu.org
2015-03-04 13:55 ` rguenther at suse dot de [this message]
2015-03-06 18:44 ` msebor at gcc dot gnu.org
2015-03-07 16:19 ` [Bug testsuite/63175] [4.9 " law at redhat dot com
2015-03-10 21:07 ` msebor at gcc dot gnu.org
2015-03-11 10:09 ` rguenth at gcc dot gnu.org
2015-03-23 18:58 ` msebor at gcc dot gnu.org
2015-05-29 16:49 ` wschmidt 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=bug-63175-4-Q0XmIcK5nr@http.gcc.gnu.org/bugzilla/ \
    --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: link
Be 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).