[Bug tree-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[Bug tree-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[janis at gcc dot gnu dot org]

------- Additional Comments From janis at gcc dot gnu dot org  2005-04-21 00:51 -------
Created an attachment (id=8694)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=8694&action=view)
minimized testcase


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug tree-optimization/21138] New: wrong code in sixtrack for -fmodulo-sched

[janis at gcc dot gnu dot org]

The SPEC CPU2000 test sixtrack gets comparison failures on
powerpc64-linux when compiled with current GCC mainline with
"-m64 -O2 -fmodulo-sched".  The minimized testcase demonstrates
the problem.  It starts failing with sources as of 20050405.

-- 
           Summary: wrong code in sixtrack for -fmodulo-sched
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: janis at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org,hagog at gcc dot gnu dot
                    org
 GCC build triplet: powerpc64-linux
  GCC host triplet: powerpc64-linux
GCC target triplet: powerpc64-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|tree-optimization           |rtl-optimization
           Keywords|                            |wrong-code


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[janis at gcc dot gnu dot org]

------- Additional Comments From janis at gcc dot gnu dot org  2005-04-22 00:26 -------
The testcase starts failing with this patch from rakdver:
  http://gcc.gnu.org/ml/gcc-cvs/2005-04/msg00301.html

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[rakdver at gcc dot gnu dot org]

------- Additional Comments From rakdver at gcc dot gnu dot org  2005-04-22 13:56 -------
As far as I can tell, the code at .final_cleanup dump is correct, 
so the patch most likely reveals some latent bug in sms or one of 
the later passes. 

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2005-04-22 13:56:43
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[janis at gcc dot gnu dot org]

------- Additional Comments From janis at gcc dot gnu dot org  2005-04-28 00:07 -------
There are other SPEC CPU2000 comparison failures on powerpc64-linux
with "-m64 -O2 -fmodulo-sched" that resist attempts to minimize the
testcases.  apsi has been failing since:
                                                                                
  http://gcc.gnu.org/ml/gcc-cvs/2005-04/msg00893.html from kazu
                                                                                
and lucas has been failing since:
                                                                                
  http://gcc.gnu.org/ml/gcc-cvs/2005-04/msg01289.html from radkver.
                                                                                
While trying to minimize the apsi failure I added write statements
that caused apsi to segfault; for example, write the value of I just
inside the loop using it in DCDTZ with:
                                                                                
1327a1328,1329
>             write(6,1001) i
> 1001        format(' i = ',i3)
                                                                                
I'm adding the information to this PR because I don't have test cases
to submit for the apsi and lucas failures in new PRs, and hope that
the information might be useful to Mostafa or anyone else who looks
into this PR.  There were other failures with these options earlier
this month that have since gone away, making it look even more like
latent bugs in the modulo scheduling code.
                                                                                
All of these SPEC CPU2000 failures are with the small "test" input.

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[mustafa at il dot ibm dot com]

------- Additional Comments From mustafa at il dot ibm dot com  2005-05-04 12:31 -------
Is seems like this is not an SMS bug, sixtrack is failing for me with -m64 -O2
without -fmodulo-sched. 
Jania, have you checked that and have a different results?

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[janis at gcc dot gnu dot org]

------- Additional Comments From janis at gcc dot gnu dot org  2005-05-09 19:32 -------
sixtrack works fine for me with "-m64 -O2" with both SPEC's test input and its
ref output, for all of my daily builds since 20050503, while with the addition
of -fmodulo-sched it gets miscompares.  lucas is now passing again, but apsi is
still gettting miscompares with "-m64 -O2 -fmodulo-sched".

Every week or so I run SPEC CPU2000 with GCC mainline built the previous night
and run the tests using "test" input, for each of about 40 sets of GCC command
line options with -m32 and then with -m64.  This has found several regressions
(21272, 21155, 21054, 21048, 21030, 20813 in the last month).  Almost all of
the failures I see are ICEs; the ones reported here with -fmodulo-sched are
the only runtime failures I've seen for a long time.

I'm running the tests now with the 20050508 compiler (last night's build
failed) and will let you know if failures with other options look related
to this one.  The only known problem right now is PR 21155, intermittent
ICEs with -ftree-vectorize.

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[janis at gcc dot gnu dot org]

------- Additional Comments From janis at gcc dot gnu dot org  2005-05-16 20:27 -------
sixtrack and the testcase smsbug.f still fail on powerpc64-linux when compiled
with mainline GCC with the options "-m64 -O2 -fmodulo-sched".  The other
failures with those options mentioned in comment #4 have gone away.

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[mustafa at il dot ibm dot com]

------- Additional Comments From mustafa at il dot ibm dot com  2005-05-17 15:05 -------
Janis, can you try this patch?

Index: modulo-sched.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/modulo-sched.c,v
retrieving revision 1.29
diff -c -p -r1.29 modulo-sched.c
*** modulo-sched.c      28 Apr 2005 02:25:22 -0000      1.29
--- modulo-sched.c      17 May 2005 11:47:00 -0000
*************** undo_generate_reg_moves (partial_schedul
*** 597,602 ****
--- 597,603 ----
          delete_insn (crr);
          crr = prev;
        }
+       SCHED_FIRST_REG_MOVE (u) = NULL_RTX;
      }
   
    while (reg_move_replaces)


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[janis187 at us dot ibm dot com]

------- Additional Comments From janis187 at us dot ibm dot com  2005-05-17 20:01 -------
Subject: Re:  wrong code in sixtrack for -fmodulo-sched

The patch fixes the problem with sixtrack.

I suspected that a latent problem was causing the earlier failures in
lucas and apsi which have since gone away.  They failed on 20050429,
but with the patch applied to sources from that date they pass.  Yea!


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2005-06-01 05:26 -------
Subject: Bug 21138

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	hagog@gcc.gnu.org	2005-06-01 05:26:45

Modified files:
	gcc            : ChangeLog modulo-sched.c 

Log message:
	2005-06-01 Mostafa Hagog <mustafa@il.ibm.com>
	
	* modulo-sched.c (undo_generate_reg_moves ): Fix PR 21138.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.8968&r2=2.8969
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/modulo-sched.c.diff?cvsroot=gcc&r1=1.30&r2=1.31



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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138

[Bug rtl-optimization/21138] wrong code in sixtrack for -fmodulo-sched

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-06-01 19:17 -------
Fixed.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.1.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21138