public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug tree-optimization/38723]  New: default definitions not in avail_out
@ 2009-01-04 18:40 rguenth at gcc dot gnu dot org
  2009-01-04 21:34 ` [Bug tree-optimization/38723] " rguenth at gcc dot gnu dot org
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2009-01-04 18:40 UTC (permalink / raw)
  To: gcc-bugs

FRE does not optimize

int i;
int foo (void)
{
  int j;
  i = j;
  return i;
}

because j_1(D) is never in AVAIL_OUT, so we do not find a leader for it.

We can fix this by either pretending used default definitions are defined
in the entry block or by treating default definitions the same as constants
during elimination.

Danny?


-- 
           Summary: default definitions not in avail_out
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rguenth at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38723


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug tree-optimization/38723] default definitions not in avail_out
  2009-01-04 18:40 [Bug tree-optimization/38723] New: default definitions not in avail_out rguenth at gcc dot gnu dot org
@ 2009-01-04 21:34 ` rguenth at gcc dot gnu dot org
  2009-01-04 22:35 ` dberlin at dberlin dot org
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2009-01-04 21:34 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #1 from rguenth at gcc dot gnu dot org  2009-01-04 21:34 -------
Subject: Bug 38723

Author: rguenth
Date: Sun Jan  4 21:33:46 2009
New Revision: 143059

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=143059
Log:
2009-01-04  Richard Guenther  <rguenther@suse.de>

        PR tree-optimization/38723
        * tree-ssa-alias.c (maybe_skip_until): Use get_continuation_for_phi.
        * tree-ssa-pre.c (compute_avail): Add all default definitions to
        the entry block.

Modified:
    branches/alias-improvements/gcc/ChangeLog.alias
    branches/alias-improvements/gcc/tree-ssa-alias.c
    branches/alias-improvements/gcc/tree-ssa-pre.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38723


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug tree-optimization/38723] default definitions not in avail_out
  2009-01-04 18:40 [Bug tree-optimization/38723] New: default definitions not in avail_out rguenth at gcc dot gnu dot org
  2009-01-04 21:34 ` [Bug tree-optimization/38723] " rguenth at gcc dot gnu dot org
@ 2009-01-04 22:35 ` dberlin at dberlin dot org
  2009-01-04 23:05 ` rguenth at gcc dot gnu dot org
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: dberlin at dberlin dot org @ 2009-01-04 22:35 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #2 from dberlin at gcc dot gnu dot org  2009-01-04 22:35 -------
Subject: Re:  New: default definitions not in avail_out

At one time we pretended they were defined in the entry block, and
IIRC, it worked out okay.
Dunno what happened to this :)


On Sun, Jan 4, 2009 at 1:40 PM, rguenth at gcc dot gnu dot org
<gcc-bugzilla@gcc.gnu.org> wrote:
> FRE does not optimize
>
> int i;
> int foo (void)
> {
>  int j;
>  i = j;
>  return i;
> }
>
> because j_1(D) is never in AVAIL_OUT, so we do not find a leader for it.
>
> We can fix this by either pretending used default definitions are defined
> in the entry block or by treating default definitions the same as constants
> during elimination.
>
> Danny?
>
>
> --
>           Summary: default definitions not in avail_out
>           Product: gcc
>           Version: 4.4.0
>            Status: UNCONFIRMED
>          Keywords: missed-optimization
>          Severity: enhancement
>          Priority: P3
>         Component: tree-optimization
>        AssignedTo: unassigned at gcc dot gnu dot org
>        ReportedBy: rguenth at gcc dot gnu dot org
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38723
>
> ------- You are receiving this mail because: -------
> You are on the CC list for the bug, or are watching someone who is.
>


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38723


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug tree-optimization/38723] default definitions not in avail_out
  2009-01-04 18:40 [Bug tree-optimization/38723] New: default definitions not in avail_out rguenth at gcc dot gnu dot org
  2009-01-04 21:34 ` [Bug tree-optimization/38723] " rguenth at gcc dot gnu dot org
  2009-01-04 22:35 ` dberlin at dberlin dot org
@ 2009-01-04 23:05 ` rguenth at gcc dot gnu dot org
  2009-03-28 17:18 ` rguenth at gcc dot gnu dot org
  2009-03-28 17:18 ` rguenth at gcc dot gnu dot org
  4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2009-01-04 23:05 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #3 from rguenth at gcc dot gnu dot org  2009-01-04 23:05 -------
Mine.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rguenth at gcc dot gnu dot
                   |dot org                     |org
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-01-04 23:05:37
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38723


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug tree-optimization/38723] default definitions not in avail_out
  2009-01-04 18:40 [Bug tree-optimization/38723] New: default definitions not in avail_out rguenth at gcc dot gnu dot org
                   ` (2 preceding siblings ...)
  2009-01-04 23:05 ` rguenth at gcc dot gnu dot org
@ 2009-03-28 17:18 ` rguenth at gcc dot gnu dot org
  2009-03-28 17:18 ` rguenth at gcc dot gnu dot org
  4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2009-03-28 17:18 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #5 from rguenth at gcc dot gnu dot org  2009-03-28 17:18 -------
Subject: Bug 38723

Author: rguenth
Date: Sat Mar 28 17:17:57 2009
New Revision: 145197

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=145197
Log:
2009-03-28  Richard Guenther  <rguenther@suse.de>

        PR tree-optimization/38723
        * tree-ssa-pre.c (compute_avail): Add all default definitions to
        the entry block.

        * gcc.dg/tree-ssa/ssa-fre-22.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-22.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-pre.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38723


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug tree-optimization/38723] default definitions not in avail_out
  2009-01-04 18:40 [Bug tree-optimization/38723] New: default definitions not in avail_out rguenth at gcc dot gnu dot org
                   ` (3 preceding siblings ...)
  2009-03-28 17:18 ` rguenth at gcc dot gnu dot org
@ 2009-03-28 17:18 ` rguenth at gcc dot gnu dot org
  4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2009-03-28 17:18 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #4 from rguenth at gcc dot gnu dot org  2009-03-28 17:18 -------
Fixed.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38723


^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2009-03-28 17:18 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2009-01-04 18:40 [Bug tree-optimization/38723] New: default definitions not in avail_out rguenth at gcc dot gnu dot org
2009-01-04 21:34 ` [Bug tree-optimization/38723] " rguenth at gcc dot gnu dot org
2009-01-04 22:35 ` dberlin at dberlin dot org
2009-01-04 23:05 ` rguenth at gcc dot gnu dot org
2009-03-28 17:18 ` rguenth at gcc dot gnu dot org
2009-03-28 17:18 ` rguenth at gcc dot gnu dot org

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).