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* [Bug tree-optimization/22041] Reverse loop order for increased efficiency
       [not found] <bug-22041-10391@http.gcc.gnu.org/bugzilla/>
@ 2006-02-27 14:06 ` steven at gcc dot gnu dot org
  2006-05-28 14:10 ` tkoenig at gcc dot gnu dot org
                   ` (2 subsequent siblings)
  3 siblings, 0 replies; 9+ messages in thread
From: steven at gcc dot gnu dot org @ 2006-02-27 14:06 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #3 from steven at gcc dot gnu dot org  2006-02-27 14:06 -------
Dunno if tree loop reversal is already there, but Zdenek probably likes to know
what bugs he is fixing...


-- 

steven at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rakdver at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22041


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug tree-optimization/22041] Reverse loop order for increased efficiency
       [not found] <bug-22041-10391@http.gcc.gnu.org/bugzilla/>
  2006-02-27 14:06 ` [Bug tree-optimization/22041] Reverse loop order for increased efficiency steven at gcc dot gnu dot org
@ 2006-05-28 14:10 ` tkoenig at gcc dot gnu dot org
  2006-05-28 14:25 ` rakdver at atrey dot karlin dot mff dot cuni dot cz
  2006-06-05 21:36 ` tkoenig at gcc dot gnu dot org
  3 siblings, 0 replies; 9+ messages in thread
From: tkoenig at gcc dot gnu dot org @ 2006-05-28 14:10 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #4 from tkoenig at gcc dot gnu dot org  2006-05-28 14:10 -------
(In reply to comment #3)
> Dunno if tree loop reversal is already there, but Zdenek probably likes to know
> what bugs he is fixing...

Loop reversal doesn't occur yet.

gcc version 4.2.0 20060521 (experimental) gives us:

L4:
        movl    (%ecx), %eax
        addl    $1, %ebx
        addl    %edi, %ecx
        movl    %eax, (%edx)
        addl    %esi, %edx
        cmpl    16(%ebp), %ebx
        jne     L4


-- 

tkoenig at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2005-12-24 20:30:10         |2006-05-28 14:10:44
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22041


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug tree-optimization/22041] Reverse loop order for increased efficiency
       [not found] <bug-22041-10391@http.gcc.gnu.org/bugzilla/>
  2006-02-27 14:06 ` [Bug tree-optimization/22041] Reverse loop order for increased efficiency steven at gcc dot gnu dot org
  2006-05-28 14:10 ` tkoenig at gcc dot gnu dot org
@ 2006-05-28 14:25 ` rakdver at atrey dot karlin dot mff dot cuni dot cz
  2006-06-05 21:36 ` tkoenig at gcc dot gnu dot org
  3 siblings, 0 replies; 9+ messages in thread
From: rakdver at atrey dot karlin dot mff dot cuni dot cz @ 2006-05-28 14:25 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #5 from rakdver at atrey dot karlin dot mff dot cuni dot cz  2006-05-28 14:25 -------
Subject: Re:  Reverse loop order for increased efficiency

> ------- Comment #4 from tkoenig at gcc dot gnu dot org  2006-05-28 14:10 -------
> (In reply to comment #3)
> > Dunno if tree loop reversal is already there, but Zdenek probably likes to know
> > what bugs he is fixing...
> 
> Loop reversal doesn't occur yet.
> 
> gcc version 4.2.0 20060521 (experimental) gives us:
> 
> L4:
>         movl    (%ecx), %eax
>         addl    $1, %ebx
>         addl    %edi, %ecx
>         movl    %eax, (%edx)
>         addl    %esi, %edx
>         cmpl    16(%ebp), %ebx
>         jne     L4

loop reversal was removed with the old loop optimizer; the tree level
loop reversal patch
(http://gcc.gnu.org/ml/gcc-patches/2006-01/msg01851.html) was not
reviewed.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22041


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug tree-optimization/22041] Reverse loop order for increased efficiency
       [not found] <bug-22041-10391@http.gcc.gnu.org/bugzilla/>
                   ` (2 preceding siblings ...)
  2006-05-28 14:25 ` rakdver at atrey dot karlin dot mff dot cuni dot cz
@ 2006-06-05 21:36 ` tkoenig at gcc dot gnu dot org
  3 siblings, 0 replies; 9+ messages in thread
From: tkoenig at gcc dot gnu dot org @ 2006-06-05 21:36 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #6 from tkoenig at gcc dot gnu dot org  2006-06-05 21:30 -------
(In reply to comment #5)

> loop reversal was removed with the old loop optimizer; the tree level
> loop reversal patch
> (http://gcc.gnu.org/ml/gcc-patches/2006-01/msg01851.html) was not
> reviewed.

Does this make this PR a regresion (technically)?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22041


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug tree-optimization/22041] Reverse loop order for increased efficiency
       [not found] <bug-22041-4@http.gcc.gnu.org/bugzilla/>
  2010-12-30 12:29 ` tkoenig at gcc dot gnu.org
  2013-03-17 17:13 ` tkoenig at gcc dot gnu.org
@ 2021-03-03 18:47 ` pinskia at gcc dot gnu.org
  2 siblings, 0 replies; 9+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-03-03 18:47 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=22041

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |stefan at franke dot ms

--- Comment #10 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 99364 has been marked as a duplicate of this bug. ***

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug tree-optimization/22041] Reverse loop order for increased efficiency
       [not found] <bug-22041-4@http.gcc.gnu.org/bugzilla/>
  2010-12-30 12:29 ` tkoenig at gcc dot gnu.org
@ 2013-03-17 17:13 ` tkoenig at gcc dot gnu.org
  2021-03-03 18:47 ` pinskia at gcc dot gnu.org
  2 siblings, 0 replies; 9+ messages in thread
From: tkoenig at gcc dot gnu.org @ 2013-03-17 17:13 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22041

Thomas Koenig <tkoenig at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2010-12-30 12:00:00         |2013-03-17 12:00
      Known to fail|                            |4.9.0

--- Comment #8 from Thomas Koenig <tkoenig at gcc dot gnu.org> 2013-03-17 17:13:24 UTC ---
Still isn't implemented on current trunk.


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug tree-optimization/22041] Reverse loop order for increased efficiency
       [not found] <bug-22041-4@http.gcc.gnu.org/bugzilla/>
@ 2010-12-30 12:29 ` tkoenig at gcc dot gnu.org
  2013-03-17 17:13 ` tkoenig at gcc dot gnu.org
  2021-03-03 18:47 ` pinskia at gcc dot gnu.org
  2 siblings, 0 replies; 9+ messages in thread
From: tkoenig at gcc dot gnu.org @ 2010-12-30 12:29 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22041

Thomas Koenig <tkoenig at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2006-05-28 14:10:44         |2010-12-30 12:00

--- Comment #7 from Thomas Koenig <tkoenig at gcc dot gnu.org> 2010-12-30 12:29:14 UTC ---
This is still an issue with current trunk -
stride.c gives worse code than stride-2.c with -O2.
Specifying -fivopts doesn't make a difference.  This is for
x86_64-unknown-linux-gnu.


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug tree-optimization/22041] Reverse loop order for increased efficiency
  2005-06-12 20:57 [Bug tree-optimization/22041] New: " tkoenig at gcc dot gnu dot org
  2005-06-12 23:44 ` [Bug tree-optimization/22041] " pinskia at gcc dot gnu dot org
@ 2005-07-07 23:42 ` pinskia at gcc dot gnu dot org
  1 sibling, 0 replies; 9+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-07-07 23:42 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From pinskia at gcc dot gnu dot org  2005-07-07 23:42 -------
IIRC loop.c does the reversal so we need to move to the tree level.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pinskia at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22041


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug tree-optimization/22041] Reverse loop order for increased efficiency
  2005-06-12 20:57 [Bug tree-optimization/22041] New: " tkoenig at gcc dot gnu dot org
@ 2005-06-12 23:44 ` pinskia at gcc dot gnu dot org
  2005-07-07 23:42 ` pinskia at gcc dot gnu dot org
  1 sibling, 0 replies; 9+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-06-12 23:44 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From pinskia at gcc dot gnu dot org  2005-06-12 23:44 -------
Confirmed, on ppc-darwin we do reverse the loop and we use the do-loop patterns:
L4:
        lfsx f0,r2,r4
        add r2,r2,r7
        stfsx f0,r3,r0
        add r0,r0,r6
        bdnz L4
L11:
        lfsx f0,r2,r4
        add r2,r2,r7
        stfsx f0,r3,r0
        add r0,r0,r6
        bdnz L11

So we could improve for x86.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2005-06-12 23:44:37
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22041


^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2021-03-03 18:47 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
     [not found] <bug-22041-10391@http.gcc.gnu.org/bugzilla/>
2006-02-27 14:06 ` [Bug tree-optimization/22041] Reverse loop order for increased efficiency steven at gcc dot gnu dot org
2006-05-28 14:10 ` tkoenig at gcc dot gnu dot org
2006-05-28 14:25 ` rakdver at atrey dot karlin dot mff dot cuni dot cz
2006-06-05 21:36 ` tkoenig at gcc dot gnu dot org
     [not found] <bug-22041-4@http.gcc.gnu.org/bugzilla/>
2010-12-30 12:29 ` tkoenig at gcc dot gnu.org
2013-03-17 17:13 ` tkoenig at gcc dot gnu.org
2021-03-03 18:47 ` pinskia at gcc dot gnu.org
2005-06-12 20:57 [Bug tree-optimization/22041] New: " tkoenig at gcc dot gnu dot org
2005-06-12 23:44 ` [Bug tree-optimization/22041] " pinskia at gcc dot gnu dot org
2005-07-07 23:42 ` pinskia at gcc dot gnu dot org

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