[Bug tree-optimization/111478] New: [12/13/14 regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[Bug tree-optimization/111478] New: [12/13/14 regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[nsz at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

            Bug ID: 111478
           Summary: [12/13/14 regression] aarch64 SVE ICE: in
                    compute_live_loop_exits, at tree-ssa-loop-manip.cc:250
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nsz at gcc dot gnu.org
  Target Milestone: ---

$ cat bug.c
float a, d, e, f, g;
int b, c;
void h() {
  for (; b; b++) {
    for (; c;) {
      float i = d = i;
    }
    a += f - e * g;
    a += g + e * f;
  }
}


$ gcc -c -O3 -march=armv8-a+sve bug.c
during GIMPLE pass: vect
<source>: In function 'h':
<source>:3:6: internal compiler error: in compute_live_loop_exits, at
tree-ssa-loop-manip.cc:250
    3 | void h() {
      |      ^
0x1168eb4 compute_live_loop_exits
       
/data/jenkins/workspace/GNU-toolchain/fsf-trunk/src/gcc/gcc/tree-ssa-loop-manip.cc:250
0x1168eb4 add_exit_phis_var
       
/data/jenkins/workspace/GNU-toolchain/fsf-trunk/src/gcc/gcc/tree-ssa-loop-manip.cc:332
0x1168eb4 add_exit_phis
       
/data/jenkins/workspace/GNU-toolchain/fsf-trunk/src/gcc/gcc/tree-ssa-loop-manip.cc:393
0x1168eb4 rewrite_into_loop_closed_ssa_1
       
/data/jenkins/workspace/GNU-toolchain/fsf-trunk/src/gcc/gcc/tree-ssa-loop-manip.cc:606
0x1168eb4 rewrite_into_loop_closed_ssa(bitmap_head*, unsigned int)
       
/data/jenkins/workspace/GNU-toolchain/fsf-trunk/src/gcc/gcc/tree-ssa-loop-manip.cc:628
0x130a1e8 execute
       
/data/jenkins/workspace/GNU-toolchain/fsf-trunk/src/gcc/gcc/tree-vectorizer.cc:1358
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
Compiler returned: 1

[Bug tree-optimization/111478] [12/13/14 regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[nsz at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

--- Comment #1 from nsz at gcc dot gnu.org ---
see also bug 111479

[Bug tree-optimization/111478] [12/13/14 regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|                            |aarch64
   Last reconfirmed|                            |2023-09-19
     Ever confirmed|0                           |1
   Target Milestone|---                         |14.0
             Status|UNCONFIRMED                 |NEW

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.  We have a two-operator operation in the preheader instead of in the
loop body.  IIRC we have a duplicate for this, this is all invariant operations
and we get confused applying loop masking to it somehow.

[Bug tree-optimization/111478] [12/13/14 regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ktkachov at gcc dot gnu.org
   Target Milestone|14.0                        |12.4
           Priority|P3                          |P1

--- Comment #3 from ktkachov at gcc dot gnu.org ---
Marking as P1. We hit this with a Fortran reproducer:
      SUBROUTINE REPRODUCER( M, A, LDA )
      IMPLICIT NONE
      INTEGER            LDA, M, I
      COMPLEX            A( LDA, * )
      DO I = 2, M
        A( I, 1 ) = A( I, 1 ) / A( 1, 1 )
      END DO
      RETURN
      END

on aarch64 with -march=armv8-a+sve -O3
The ICE triggeres on 12.3 but compiles fine wiht 12.2

[Bug tree-optimization/111478] [12/13/14 regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I can't reproduce either of the testcases here any more .

[Bug tree-optimization/111478] [12/13/14 regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #4)
> I can't reproduce either of the testcases here any more .

I should say on the trunk.

[Bug tree-optimization/111478] [12/13 Regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[12/13/14 regression]       |[12/13 Regression] aarch64
                   |aarch64 SVE ICE: in         |SVE ICE: in
                   |compute_live_loop_exits, at |compute_live_loop_exits, at
                   |tree-ssa-loop-manip.cc:250  |tree-ssa-loop-manip.cc:250
             Status|NEW                         |ASSIGNED
      Known to work|                            |14.0
           Priority|P1                          |P2
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot gnu.org

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed by r14-5320-ge5f1956498251a4973d52c8aad3faf34d0443169, I'll take that for
backporting.

[Bug tree-optimization/111478] [12 Regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[12/13 Regression] aarch64  |[12 Regression] aarch64 SVE
                   |SVE ICE: in                 |ICE: in
                   |compute_live_loop_exits, at |compute_live_loop_exits, at
                   |tree-ssa-loop-manip.cc:250  |tree-ssa-loop-manip.cc:250
      Known to work|                            |13.2.1

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
Backported to GCC 13.

[Bug tree-optimization/111478] [12 Regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[saurabh.jha at arm dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

--- Comment #8 from Saurabh Jha <saurabh.jha at arm dot com> ---
Hi Richard,

Are you also planning to backport it to gcc-12?

Regards,
Saurabh

[Bug tree-optimization/111478] [12 Regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Saurabh Jha from comment #8)
> Hi Richard,
> 
> Are you also planning to backport it to gcc-12?

Yes.

[Bug tree-optimization/111478] [12 Regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[avieira at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

avieira at gcc dot gnu.org changed:

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

--- Comment #10 from avieira at gcc dot gnu.org ---
This has now been backported to gcc-13 and gcc-12, so I think we should close,
will leave that to Richard.

[Bug tree-optimization/111478] [12 Regression] aarch64 SVE ICE: in compute_live_loop_exits, at tree-ssa-loop-manip.cc:250

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111478

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

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

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