[Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale

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* [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale
@ 2012-10-26 21:54 hjl.tools at gmail dot com
  2012-10-26 22:13 ` [Bug rtl-optimization/55092] " jakub at gcc dot gnu.org
                   ` (13 more replies)
  0 siblings, 14 replies; 15+ messages in thread
From: hjl.tools at gmail dot com @ 2012-10-26 21:54 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

             Bug #: 55092
           Summary: [4.8 Regression] LRA doesn't scale
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: hjl.tools@gmail.com
                CC: vmakarov@redhat.com


From

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54402#c4

-----
As Uros says in bug 54507, the reflect test from libgo is another example.
Without var tracking it takes 20s on my x86_64 box (tested with a 32-bit
compiler).  With var tracking it takes 46m 40s.
-----

It only happens with -m32.  It takes less than 20 seconds for
-m64 and -mx32. Turn-off LRA takes only 13 seconds to finish.


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8 Regression] LRA doesn't scale
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
@ 2012-10-26 22:13 ` jakub at gcc dot gnu.org
  2012-10-26 22:50 ` vmakarov at redhat dot com
                   ` (12 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: jakub at gcc dot gnu.org @ 2012-10-26 22:13 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-10-26 22:13:09 UTC ---
It isn't LRA that doesn't scale, it is var-tracking memory clobbering that
needs improvements, but it would be nice to analyze what are the changes that
LRA does compared to reload that make var-tracking to take that much longer and
whether the generated code is better or worse.  If it is better, this is just
PR54402 dup.


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8 Regression] LRA doesn't scale
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
  2012-10-26 22:13 ` [Bug rtl-optimization/55092] " jakub at gcc dot gnu.org
@ 2012-10-26 22:50 ` vmakarov at redhat dot com
  2012-10-26 22:57 ` hjl.tools at gmail dot com
                   ` (11 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: vmakarov at redhat dot com @ 2012-10-26 22:50 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

--- Comment #2 from Vladimir Makarov <vmakarov at redhat dot com> 2012-10-26 22:49:23 UTC ---
 LRA reuses stack memory much better than reload (in all modes but especially
in -O0).  May be that is the reason of the var-tracking problem.


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8 Regression] LRA doesn't scale
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
  2012-10-26 22:13 ` [Bug rtl-optimization/55092] " jakub at gcc dot gnu.org
  2012-10-26 22:50 ` vmakarov at redhat dot com
@ 2012-10-26 22:57 ` hjl.tools at gmail dot com
  2012-10-26 22:58 ` vmakarov at redhat dot com
                   ` (10 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: hjl.tools at gmail dot com @ 2012-10-26 22:57 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

--- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> 2012-10-26 22:56:55 UTC ---
The testcase is compiled with -O2, not -O0.


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8 Regression] LRA doesn't scale
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (2 preceding siblings ...)
  2012-10-26 22:57 ` hjl.tools at gmail dot com
@ 2012-10-26 22:58 ` vmakarov at redhat dot com
  2012-10-26 23:03 ` hjl.tools at gmail dot com
                   ` (9 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: vmakarov at redhat dot com @ 2012-10-26 22:58 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

--- Comment #4 from Vladimir Makarov <vmakarov at redhat dot com> 2012-10-26 22:57:38 UTC ---
(In reply to comment #2)
>  LRA reuses stack memory much better than reload (in all modes but especially
> in -O0).  May be that is the reason of the var-tracking problem.

I forgot to say that LRA understands -fno-ira-share-spill-slots.  In this case,
 each pseudo gets own stack slot.

I thing it is worth to try it.


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8 Regression] LRA doesn't scale
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (3 preceding siblings ...)
  2012-10-26 22:58 ` vmakarov at redhat dot com
@ 2012-10-26 23:03 ` hjl.tools at gmail dot com
  2012-10-27 13:32 ` [Bug rtl-optimization/55092] [4.8 Regression] LRA aggravates var-tracking scalability problems steven at gcc dot gnu.org
                   ` (8 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: hjl.tools at gmail dot com @ 2012-10-26 23:03 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

--- Comment #5 from H.J. Lu <hjl.tools at gmail dot com> 2012-10-26 23:03:05 UTC ---
-fno-ira-share-spill-slots doesn't make a difference.


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8 Regression] LRA aggravates var-tracking scalability problems
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (4 preceding siblings ...)
  2012-10-26 23:03 ` hjl.tools at gmail dot com
@ 2012-10-27 13:32 ` steven at gcc dot gnu.org
  2012-10-29 14:35 ` rguenth at gcc dot gnu.org
                   ` (7 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: steven at gcc dot gnu.org @ 2012-10-27 13:32 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

Steven Bosscher <steven at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |compile-time-hog
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-10-27
         Depends on|                            |54402
            Summary|[4.8 Regression] LRA        |[4.8 Regression] LRA
                   |doesn't scale               |aggravates var-tracking
                   |                            |scalability problems
     Ever Confirmed|0                           |1


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8 Regression] LRA aggravates var-tracking scalability problems
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (5 preceding siblings ...)
  2012-10-27 13:32 ` [Bug rtl-optimization/55092] [4.8 Regression] LRA aggravates var-tracking scalability problems steven at gcc dot gnu.org
@ 2012-10-29 14:35 ` rguenth at gcc dot gnu.org
  2012-12-10 10:54 ` jakub at gcc dot gnu.org
                   ` (6 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: rguenth at gcc dot gnu.org @ 2012-10-29 14:35 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.8.0


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8 Regression] LRA aggravates var-tracking scalability problems
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (6 preceding siblings ...)
  2012-10-29 14:35 ` rguenth at gcc dot gnu.org
@ 2012-12-10 10:54 ` jakub at gcc dot gnu.org
  2013-02-26 15:15 ` rguenth at gcc dot gnu.org
                   ` (5 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: jakub at gcc dot gnu.org @ 2012-12-10 10:54 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-12-10 10:53:50 UTC ---
I believe on that testcase it was because without LRA the function didn't use a
frame pointer, while with LRA for some reason it does.


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8 Regression] LRA aggravates var-tracking scalability problems
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (7 preceding siblings ...)
  2012-12-10 10:54 ` jakub at gcc dot gnu.org
@ 2013-02-26 15:15 ` rguenth at gcc dot gnu.org
  2013-03-22 14:48 ` [Bug rtl-optimization/55092] [4.8/4.9 " jakub at gcc dot gnu.org
                   ` (4 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: rguenth at gcc dot gnu.org @ 2013-02-26 15:15 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |WAITING

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> 2013-02-26 15:15:27 UTC ---
(In reply to comment #6)
> I believe on that testcase it was because without LRA the function didn't use a
> frame pointer, while with LRA for some reason it does.

Can we make this bug a dup or is this now about IRA vs. LRA and the frame
pointer issue?


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8/4.9 Regression] LRA aggravates var-tracking scalability problems
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (8 preceding siblings ...)
  2013-02-26 15:15 ` rguenth at gcc dot gnu.org
@ 2013-03-22 14:48 ` jakub at gcc dot gnu.org
  2013-05-31 10:59 ` jakub at gcc dot gnu.org
                   ` (3 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: jakub at gcc dot gnu.org @ 2013-03-22 14:48 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.8.0                       |4.8.1

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-03-22 14:45:08 UTC ---
GCC 4.8.0 is being released, adjusting target milestone.


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8/4.9 Regression] LRA aggravates var-tracking scalability problems
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (9 preceding siblings ...)
  2013-03-22 14:48 ` [Bug rtl-optimization/55092] [4.8/4.9 " jakub at gcc dot gnu.org
@ 2013-05-31 10:59 ` jakub at gcc dot gnu.org
  2013-10-16  9:49 ` jakub at gcc dot gnu.org
                   ` (2 subsequent siblings)
  13 siblings, 0 replies; 15+ messages in thread
From: jakub at gcc dot gnu.org @ 2013-05-31 10:59 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.8.1                       |4.8.2

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 4.8.1 has been released.


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8/4.9 Regression] LRA aggravates var-tracking scalability problems
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (10 preceding siblings ...)
  2013-05-31 10:59 ` jakub at gcc dot gnu.org
@ 2013-10-16  9:49 ` jakub at gcc dot gnu.org
  2013-10-25 11:20 ` rguenth at gcc dot gnu.org
  2013-10-25 11:48 ` rguenth at gcc dot gnu.org
  13 siblings, 0 replies; 15+ messages in thread
From: jakub at gcc dot gnu.org @ 2013-10-16  9:49 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.8.2                       |4.8.3

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 4.8.2 has been released.


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8/4.9 Regression] LRA aggravates var-tracking scalability problems
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (11 preceding siblings ...)
  2013-10-16  9:49 ` jakub at gcc dot gnu.org
@ 2013-10-25 11:20 ` rguenth at gcc dot gnu.org
  2013-10-25 11:48 ` rguenth at gcc dot gnu.org
  13 siblings, 0 replies; 15+ messages in thread
From: rguenth at gcc dot gnu.org @ 2013-10-25 11:20 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

Bug 55092 depends on bug 54402, which changed state.

Bug 54402 Summary: [4.8/4.9 Regression] var-tracking does not scale
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54402

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |RESOLVED
         Resolution|---                         |FIXED


^ permalink raw reply	[flat|nested] 15+ messages in thread

* [Bug rtl-optimization/55092] [4.8/4.9 Regression] LRA aggravates var-tracking scalability problems
  2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
                   ` (12 preceding siblings ...)
  2013-10-25 11:20 ` rguenth at gcc dot gnu.org
@ 2013-10-25 11:48 ` rguenth at gcc dot gnu.org
  13 siblings, 0 replies; 15+ messages in thread
From: rguenth at gcc dot gnu.org @ 2013-10-25 11:48 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55092

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |RESOLVED
         Resolution|---                         |DUPLICATE

--- Comment #11 from Richard Biener <rguenth at gcc dot gnu.org> ---


*** This bug has been marked as a duplicate of bug 54402 ***


^ permalink raw reply	[flat|nested] 15+ messages in thread

end of thread, other threads:[~2013-10-25 11:48 UTC | newest]

Thread overview: 15+ messages (download: mbox.gz / follow: Atom feed)
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2012-10-26 21:54 [Bug rtl-optimization/55092] New: [4.8 Regression] LRA doesn't scale hjl.tools at gmail dot com
2012-10-26 22:13 ` [Bug rtl-optimization/55092] " jakub at gcc dot gnu.org
2012-10-26 22:50 ` vmakarov at redhat dot com
2012-10-26 22:57 ` hjl.tools at gmail dot com
2012-10-26 22:58 ` vmakarov at redhat dot com
2012-10-26 23:03 ` hjl.tools at gmail dot com
2012-10-27 13:32 ` [Bug rtl-optimization/55092] [4.8 Regression] LRA aggravates var-tracking scalability problems steven at gcc dot gnu.org
2012-10-29 14:35 ` rguenth at gcc dot gnu.org
2012-12-10 10:54 ` jakub at gcc dot gnu.org
2013-02-26 15:15 ` rguenth at gcc dot gnu.org
2013-03-22 14:48 ` [Bug rtl-optimization/55092] [4.8/4.9 " jakub at gcc dot gnu.org
2013-05-31 10:59 ` jakub at gcc dot gnu.org
2013-10-16  9:49 ` jakub at gcc dot gnu.org
2013-10-25 11:20 ` rguenth at gcc dot gnu.org
2013-10-25 11:48 ` rguenth at gcc dot gnu.org

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