public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/32684] Missed tail call with sin/cos and sincos pass
Date: Fri, 14 Jan 2011 14:08:00 -0000	[thread overview]
Message-ID: <bug-32684-4-v9iky2bixi@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-32684-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32684

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
         AssignedTo|unassigned at gcc dot       |rguenth at gcc dot gnu.org
                   |gnu.org                     |

--- Comment #10 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-01-14 13:51:31 UTC ---
Looking here again I can't see what tailcall you would expect.  Mainline
generates

complex double
quantum_cexp (double phi)
{
  complex double sincostmp.1;
  double D.2685;
  double D.2684;
  complex double D.2683;

<bb 2>:
  sincostmp.1_5 = __builtin_cexpi (phi_1(D));
  D.2684_2 = REALPART_EXPR <sincostmp.1_5>;
  D.2685_3 = IMAGPART_EXPR <sincostmp.1_5>;
  D.2683_4 = COMPLEX_EXPR <D.2684_2, D.2685_3>;
  return D.2683_4;

which we indeed do not optimize to just

  return __builtin_cexp1 (phi_1(D));

but in the end sincos doesn't have an ABI that allows for tailcalling
or sibcalling to it.

There is a missing folding of COMPLEX_EXPR <REALPART_EXPR <x>, IMAGPART_EXPR
<x>> to x and SCCVN does not go the full way of combining binary expressions.


  parent reply	other threads:[~2011-01-14 13:51 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-32684-4@http.gcc.gnu.org/bugzilla/>
2011-01-14 13:34 ` rguenth at gcc dot gnu.org
2011-01-14 13:35 ` rguenth at gcc dot gnu.org
2011-01-14 14:08 ` rguenth at gcc dot gnu.org [this message]
2014-12-01  5:18 ` pinskia at gcc dot gnu.org
2007-07-09  3:21 [Bug tree-optimization/32684] New: " pinskia at gcc dot gnu dot org
2007-07-09  9:34 ` [Bug tree-optimization/32684] " rguenth at gcc dot gnu dot org
2007-10-09  8:36 ` chrbr at gcc dot gnu dot org
2007-10-09 10:33 ` pinskia at gcc dot gnu dot org
2007-10-09 10:34 ` pinskia at gcc dot gnu dot org
2007-10-09 13:12 ` chrbr at gcc dot gnu dot org
2007-10-09 13:15 ` chrbr at gcc dot gnu dot org
2007-10-09 17:59 ` pinskia at gcc dot gnu dot 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-32684-4-v9iky2bixi@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).