[Bug middle-end/39580] New: [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[Bug middle-end/39580] New: [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[hjl dot tools at gmail dot com]

Revision 145204:

http://gcc.gnu.org/ml/gcc-cvs/2009-03/msg00711.html

caused:

FAIL: libgomp.c++/collapse-2.C  -O3 -fomit-frame-pointer -funroll-all-loops
-finline-functions  (internal compiler error)
FAIL: libgomp.c++/collapse-2.C  -O3 -fomit-frame-pointer -funroll-all-loops
-finline-functions  (test for excess errors)
FAIL: libgomp.c++/collapse-2.C  -O3 -fomit-frame-pointer -funroll-loops 
(internal compiler error)
FAIL: libgomp.c++/collapse-2.C  -O3 -fomit-frame-pointer -funroll-loops  (test
for excess errors)

on Linux/ia64.


-- 
           Summary: [4.5 regression] Revision 145204 caused
                    libgomp.c++/collapse-2.C
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: hjl dot tools at gmail dot com
GCC target triplet: ia64-unknown-linux-gnu
OtherBugsDependingO 39579
             nThis:


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug middle-end/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[hjl dot tools at gmail dot com]

------- Comment #1 from hjl dot tools at gmail dot com  2009-03-29 18:38 -------
I got

Executing on host: /export/gnu/import/rrs/145204/bld/gcc/xgcc
-B/export/gnu/import/rrs/145204/bld/gcc/
/export/gnu/import/rrs/145204/src/libgomp/testsuite/libgomp.c++/collapse-2.C 
-B/export/gnu/import/rrs/145204/bld/ia64-unknown-linux-gnu/./libgomp/
-I/export/gnu/import/rrs/145204/bld/ia64-unknown-linux-gnu/./libgomp
-I/export/gnu/import/rrs/145204/src/libgomp/testsuite/.. -fmessage-length=0
-fopenmp  -O3 -fomit-frame-pointer -funroll-loops  -nostdinc++
-I/export/gnu/import/rrs/145204/bld/ia64-unknown-linux-gnu/libstdc++-v3/include/ia64-unknown-linux-gnu
-I/export/gnu/import/rrs/145204/bld/ia64-unknown-linux-gnu/libstdc++-v3/include
-I/export/gnu/import/rrs/145204/src/libstdc++-v3/libsupc++
-I/export/gnu/import/rrs/145204/src/libstdc++-v3/include/backward
-I/export/gnu/import/rrs/145204/src/libstdc++-v3/testsuite/util
-B/export/gnu/import/rrs/145204/bld/ia64-unknown-linux-gnu/./libgomp/../libstdc++-v3/src/.libs
  -L/export/gnu/import/rrs/145204/bld/ia64-unknown-linux-gnu/./libgomp/.libs
-lgomp
-L/export/gnu/import/rrs/145204/bld/ia64-unknown-linux-gnu/./libgomp/../libstdc++-v3/src/.libs
-lstdc++ -lm   -o ./collapse-2.exe    (timeout = 300)
/export/gnu/import/rrs/145204/src/libgomp/testsuite/libgomp.c++/collapse-2.C:
In function 'void _Z2f9I1IIiEiEv1JIT0_ES4_S4_.omp_fn.6(void*)':^M
/export/gnu/import/rrs/145204/src/libgomp/testsuite/libgomp.c++/collapse-2.C:317:
internal compiler error: in insert_in_history_vect, at sel-sched-ir.c:1514^M
Please submit a full bug report,^M
with preprocessed source if appropriate.^M
See <http://gcc.gnu.org/bugs.html> for instructions.^M
compiler exited with status 1


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug middle-end/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[jsm28 at gcc dot gnu dot org]

-- 

jsm28 at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[pinskia at gcc dot gnu dot org]

------- Comment #2 from pinskia at gcc dot gnu dot org  2009-04-16 16:13 -------
This looks like better optimizations is causing a latent bug in the
selective-scheduling to show up.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pinskia at gcc dot gnu dot
                   |                            |org
          Component|middle-end                  |rtl-optimization


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[abel at gcc dot gnu dot org]

------- Comment #3 from abel at gcc dot gnu dot org  2009-04-21 11:47 -------
Confirmed.  I will take a look.


-- 

abel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |abel at ispras dot ru
         AssignedTo|unassigned at gcc dot gnu   |abel at gcc dot gnu dot org
                   |dot org                     |
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-04-21 11:47:05
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[abel at gcc dot gnu dot org]

------- Comment #4 from abel at gcc dot gnu dot org  2009-04-21 14:16 -------
What happens in the test is that when pipelining, after several consecutive
substitutions we end up with moving expressions r64=r16-r16 and r64=r16-r51
through r16=r51, after which both expressions become r64=r51-r51, as a result
of substitution.  When merging these expressions, we hit an assert in
insert_in_history_vect.  

This assert tries to describe the situations when earlier different, and now
same expressions would have similar entries in their history of changes vector,
i.e. somewhere on their way up they were transformed on the same insn.  The
main thing in the assert is that both expressions are supposed to be equal
before this transformation was recorded.  Now we have a test case when this is
not the case.  I presume that we didn't hit this before because the situations
like ' b = c; a = b - c; ' are quite rare.

We have two choices: either to extend the assert to cover this case or to
remove it completely.  If we'd extend it, then the assert becomes not very
useful, as it basically says that all variations in the above situation are
possible.  So I'm inclined just to remove it.  This would not hurt correctness,
only in extreme rare situations like this we'd not be able to find both
expressions to move them up, but only the one, as history vector has a single
entry per uid, and thus we'd be unable to perform unification.  

So I will bootstrap/regtest the below patch.

Index: gcc/sel-sched-ir.c
===================================================================
*** gcc/sel-sched-ir.c  (revision 146520)
--- gcc/sel-sched-ir.c  (working copy)
*************** insert_in_history_vect (VEC (expr_histor
*** 1512,1525 ****
      {
        expr_history_def *phist = VEC_index (expr_history_def, vect, ind);

-       /* When merging, either old vinsns are the *same* or, if not, both
-          old and new vinsns are different pointers.  In the latter case,
-          though, new vinsns should be equal.  */
-       gcc_assert (phist->old_expr_vinsn == old_expr_vinsn
-                   || (phist->new_expr_vinsn != new_expr_vinsn
-                       && (vinsn_equal_p
-                           (phist->old_expr_vinsn, old_expr_vinsn))));
-
        /* It is possible that speculation types of expressions that were
           propagated through different paths will be different here.  In this
           case, merge the status to get the correct check later.  */


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[rguenth at gcc dot gnu dot org]

-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[abel at gcc dot gnu dot org]

------- Comment #5 from abel at gcc dot gnu dot org  2009-04-22 15:26 -------
Subject: Bug 39580

Author: abel
Date: Wed Apr 22 15:25:58 2009
New Revision: 146588

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=146588
Log:

    PR rtl-optimization/39580
    * sel-sched-ir.c (insert_in_history_vect): Remove incorrect gcc_assert.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/sel-sched-ir.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[abel at gcc dot gnu dot org]

------- Comment #6 from abel at gcc dot gnu dot org  2009-04-22 15:28 -------
Fixed by the above patch.


-- 

abel at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[doko at ubuntu dot com]

------- Comment #7 from doko at ubuntu dot com  2010-05-26 16:19 -------
seen on the 4.4 branch on ia64-linux-gnu:

$ gcc -pthread -fno-strict-aliasing -fwrapv -g -fPIC -ffast-math  -O3 -c
../RepCylBond.ilayer2/RepCylBond.c: In function 'RepCylinderBox':
layer2/RepCylBond.c:2154: internal compiler error: in insert_in_history_vect,
at sel-sched-ir.c:1514
Please submit a full bug report,
with preprocessed source if appropriate.

the very same patch applied to the 4.4 branch fixes the ICE


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[doko at ubuntu dot com]

------- Comment #8 from doko at ubuntu dot com  2010-05-26 16:19 -------
Created an attachment (id=20753)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20753&action=view)
preprocessed source


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[doko at ubuntu dot com]

------- Comment #9 from doko at ubuntu dot com  2010-05-27 06:22 -------
(From update of attachment 20753)
wrong attachment


-- 

doko at ubuntu dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #20753|0                           |1
        is obsolete|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[doko at ubuntu dot com]

------- Comment #10 from doko at ubuntu dot com  2010-05-27 06:23 -------
Created an attachment (id=20758)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20758&action=view)
preprocessed source

preprocessed source, which builds with 4.3.5.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580

[Bug rtl-optimization/39580] [4.5 regression] Revision 145204 caused libgomp.c++/collapse-2.C

[doko at gcc dot gnu dot org]

------- Comment #11 from doko at gcc dot gnu dot org  2010-05-27 06:30 -------
Subject: Bug 39580

Author: doko
Date: Thu May 27 06:29:55 2010
New Revision: 159909

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=159909
Log:
2010-05-27  Matthias Klose  <doko@ubuntu.com>

        Backport from mainline:
        2009-04-22  Andrey Belevantsev  <abel@ispras.ru>

        PR rtl-optimization/39580
        * sel-sched-ir.c (insert_in_history_vect): Remove incorrect gcc_assert.

Modified:
    branches/gcc-4_4-branch/gcc/ChangeLog
    branches/gcc-4_4-branch/gcc/sel-sched-ir.c


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39580