[Bug target/99807] New: ICE in vect_slp_analyze_node_operations_1, at tree-vect-slp.c:3727

[Bug target/99807] New: ICE in vect_slp_analyze_node_operations_1, at tree-vect-slp.c:3727

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99807

            Bug ID: 99807
           Summary: ICE in vect_slp_analyze_node_operations_1, at
                    tree-vect-slp.c:3727
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---
            Target: aarch64-linux-gnu

gfortran-11.0.1-alpha20210328 snapshot
(g:499fa254ae8c9752d8c2cf3130b13ffddfd83546) ICEs when compiling the following
testcase w/ -march=armv8.3-a -O1 -ftree-slp-vectorize:

subroutine cppco(ap, z)
  implicit none
  complex :: ap(*), z(*)

  z(1) = z(1) + z(2) * (ap(1))

  return
end subroutine cppco

% aarch64-linux-gnu-gfortran-11.0.1 -march=armv8.3-a -O1 -ftree-slp-vectorize
-c xrd4htvk.f90
during GIMPLE pass: slp
xrd4htvk.f90:1:16:

    1 | subroutine cppco(ap, z)
      |                ^
internal compiler error: in vect_slp_analyze_node_operations_1, at
tree-vect-slp.c:3727
0x7c41bf vect_slp_analyze_node_operations_1
       
/var/tmp/portage/cross-aarch64-linux-gnu/gcc-11.0.1_alpha20210328/work/gcc-11-20210328/gcc/tree-vect-slp.c:3727
0x7c41bf vect_slp_analyze_node_operations
       
/var/tmp/portage/cross-aarch64-linux-gnu/gcc-11.0.1_alpha20210328/work/gcc-11-20210328/gcc/tree-vect-slp.c:3933
0x123510b vect_slp_analyze_node_operations
       
/var/tmp/portage/cross-aarch64-linux-gnu/gcc-11.0.1_alpha20210328/work/gcc-11-20210328/gcc/tree-vect-slp.c:3913
0x123510b vect_slp_analyze_node_operations
       
/var/tmp/portage/cross-aarch64-linux-gnu/gcc-11.0.1_alpha20210328/work/gcc-11-20210328/gcc/tree-vect-slp.c:3913
0x1237972 vect_slp_analyze_operations(vec_info*)
       
/var/tmp/portage/cross-aarch64-linux-gnu/gcc-11.0.1_alpha20210328/work/gcc-11-20210328/gcc/tree-vect-slp.c:4120
0x123b01d vect_slp_analyze_bb_1
       
/var/tmp/portage/cross-aarch64-linux-gnu/gcc-11.0.1_alpha20210328/work/gcc-11-20210328/gcc/tree-vect-slp.c:4899
0x123b01d vect_slp_region
       
/var/tmp/portage/cross-aarch64-linux-gnu/gcc-11.0.1_alpha20210328/work/gcc-11-20210328/gcc/tree-vect-slp.c:4945
0x123b01d vect_slp_bbs
       
/var/tmp/portage/cross-aarch64-linux-gnu/gcc-11.0.1_alpha20210328/work/gcc-11-20210328/gcc/tree-vect-slp.c:5095
0x123ce3c vect_slp_function(function*)
       
/var/tmp/portage/cross-aarch64-linux-gnu/gcc-11.0.1_alpha20210328/work/gcc-11-20210328/gcc/tree-vect-slp.c:5181
0x12437fa execute
       
/var/tmp/portage/cross-aarch64-linux-gnu/gcc-11.0.1_alpha20210328/work/gcc-11-20210328/gcc/tree-vectorizer.c:1450

[Bug target/99807] ICE in vect_slp_analyze_node_operations_1, at tree-vect-slp.c:3727

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99807

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ktkachov at gcc dot gnu.org,
                   |                            |tnfchris at gcc dot gnu.org
           Priority|P3                          |P1
      Known to fail|                            |11.0
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
   Target Milestone|---                         |11.0
   Last reconfirmed|                            |2021-03-29
      Known to work|                            |10.2.1

--- Comment #1 from ktkachov at gcc dot gnu.org ---
Confirmed. Tamar, can you have a look please?

[Bug target/99807] [11 Regression] ICE in vect_slp_analyze_node_operations_1, at tree-vect-slp.c:3727

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99807

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot gnu.org
             Status|NEW                         |ASSIGNED

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Mine.  Some longer standing "issue".

[Bug target/99807] [11 Regression] ICE in vect_slp_analyze_node_operations_1, at tree-vect-slp.c:3727

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99807

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Just to say we currently require a ("random") SLP_TREE_REPRESENTATIVE even on
VEC_PERM_EXPR SLP nodes.  With the testcase the choosen one is no longer
explicitely referenced and thus it does not get marked by SLP.  Note this will
also cause it to turn hybrid - so it's probably one of the cases where the
SLP marking as patterns "helped".

[Bug target/99807] [11 Regression] ICE in vect_slp_analyze_node_operations_1, at tree-vect-slp.c:3727

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99807

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #3)
> Just to say we currently require a ("random") SLP_TREE_REPRESENTATIVE even on
> VEC_PERM_EXPR SLP nodes.  With the testcase the choosen one is no longer
> explicitely referenced and thus it does not get marked by SLP.  Note this
> will
> also cause it to turn hybrid - so it's probably one of the cases where the
> SLP marking as patterns "helped".

We can fix the ICE by delaying the assert but the other issue still shows
in costing (which also only walks participating stmts):

t.f90:5:30: note: Cost model analysis:
0x35e56c0 _25 1 times scalar_store costs 1 in body
0x35e56c0 _26 1 times scalar_store costs 1 in body
0x35e56c0 _11 + _23 1 times scalar_stmt costs 1 in body
0x35e56c0 _12 + _24 1 times scalar_stmt costs 1 in body
0x35e56c0 REALPART_EXPR <(*z_8(D))[0]> 1 times scalar_load costs 1 in body
0x35e56c0 IMAGPART_EXPR <(*z_8(D))[0]> 1 times scalar_load costs 1 in body
0x35e56c0 REALPART_EXPR <(*z_8(D))[1]> 1 times scalar_load costs 1 in body
0x35e56c0 REALPART_EXPR <(*z_8(D))[0]> 1 times unaligned_load (misalign -1)
costs 1 in body
0x35e56c0 REALPART_EXPR <(*z_8(D))[0]> 1 times vec_perm costs 2 in body
0x35e56c0 REALPART_EXPR <(*z_8(D))[1]> 1 times unaligned_load (misalign -1)
costs 1 in body
0x35e56c0 <unknown> 1 times vec_perm costs 2 in body
0x35e56c0 <unknown> 1 times vec_construct costs 2 in prologue
0x35e56c0 .COMPLEX_FMA (_25, _25, _25) 1 times vector_stmt costs 1 in body
0x35e56c0 <unknown> 1 times vec_construct costs 2 in prologue
0x35e56c0 _25 1 times unaligned_store (misalign -1) costs 1 in body
0x35e56c0 REALPART_EXPR <(*z_8(D))[1]> 1 times vec_to_scalar costs 2 in
epilogue
0x35e56c0 REALPART_EXPR <(*z_8(D))[1]> 1 times vec_to_scalar costs 2 in
epilogue
t.f90:5:30: note: Cost model analysis for part in loop 0:
  Vector cost: 16
  Scalar cost: 7
t.f90:5:30: missed: not vectorized: vectorization is not profitable.

so we're not costing all the scalar stmts covered by the .COMPLEX_FMA
expression
because scalar costing only looks at SLP_TREE_SCALAR_STMTS (it would not
cost multiple stmts covering a scalar pattern either).

That said, I'm going to fix this simple to deal with ICE now, all the rest
needs more thoughts (and I'd like to defer any solution to GCC 12 for the
moment).

[Bug target/99807] [11 Regression] ICE in vect_slp_analyze_node_operations_1, at tree-vect-slp.c:3727

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99807

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:8cf2812cfceaf464dff99651b2d911d6e12b52b7

commit r11-7889-g8cf2812cfceaf464dff99651b2d911d6e12b52b7
Author: Richard Biener <rguenther@suse.de>
Date:   Mon Mar 29 13:10:37 2021 +0200

    tree-optimization/99807 - avoid bogus assert with permute SLP node

    This avoids asserting anything on the SLP_TREE_REPRESENTATIVE of
    an SLP permute node (which shouldn't be there).

    2021-03-29  Richard Biener  <rguenther@suse.de>

            PR tree-optimization/99807
            * tree-vect-slp.c (vect_slp_analyze_node_operations_1): Move
            assert below VEC_PERM handling.

            * gfortran.dg/vect/pr99807.f90: New testcase.

[Bug target/99807] [11 Regression] ICE in vect_slp_analyze_node_operations_1, at tree-vect-slp.c:3727

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99807

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

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

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed.