[Bug tree-optimization/98766] New: SVE: ICE in tree_to_shwi with -O3 --param=avoid-fma-max-bits

[Bug tree-optimization/98766] New: SVE: ICE in tree_to_shwi with -O3 --param=avoid-fma-max-bits

[acoplan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98766

            Bug ID: 98766
           Summary: SVE: ICE in tree_to_shwi with -O3
                    --param=avoid-fma-max-bits
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: acoplan at gcc dot gnu.org
  Target Milestone: ---

The following fails:

$ cat test.c
extern int a[];
void c(short *d) {
  for (int e = 0; e < 9; e++)
    a[e] = d[e] * 2;
}
$ aarch64-elf-gcc -c test.c -march=armv8.2-a+sve -O3
--param=avoid-fma-max-bits=8
during GIMPLE pass: widening_mul
test.c: In function 'c':
test.c:2:6: internal compiler error: in tree_to_shwi, at tree.c:7448
    2 | void c(short *d) {
      |      ^
0x11684f0 tree_to_shwi(tree_node const*)
        /home/alecop01/toolchain/src/gcc/gcc/tree.c:7448
0xfd97c1 convert_mult_to_fma
        /home/alecop01/toolchain/src/gcc/gcc/tree-ssa-math-opts.c:3255
0xfda040 after_dom_children
        /home/alecop01/toolchain/src/gcc/gcc/tree-ssa-math-opts.c:4619
0x19d3d80 dom_walker::walk(basic_block_def*)
        /home/alecop01/toolchain/src/gcc/gcc/domwalk.c:352
0xfd3731 execute
        /home/alecop01/toolchain/src/gcc/gcc/tree-ssa-math-opts.c:4718
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

Removing any one of the options makes the ICE go away. It appears to ICE at any
nonzero valid value of the param (although I've not checked this exhaustively).

[Bug tree-optimization/98766] [10/11 Regression] SVE: ICE in tree_to_shwi with -O3 --param=avoid-fma-max-bits

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98766

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |10.2.1
            Summary|SVE: ICE in tree_to_shwi    |[10/11 Regression] SVE: ICE
                   |with -O3                    |in tree_to_shwi with -O3
                   |--param=avoid-fma-max-bits  |--param=avoid-fma-max-bits
   Last reconfirmed|                            |2021-01-20
           Priority|P3                          |P2
      Known to work|                            |9.3.1
   Target Milestone|---                         |10.3
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
                 CC|                            |ktkachov at gcc dot gnu.org

--- Comment #1 from ktkachov at gcc dot gnu.org ---
Confirmed.

[Bug tree-optimization/98766] [10/11 Regression] SVE: ICE in tree_to_shwi with -O3 --param=avoid-fma-max-bits

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98766

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
  bool check_defer
    = (state->m_deferring_p
       && (tree_to_shwi (TYPE_SIZE (type))
           <= param_avoid_fma_max_bits));

known_le (tree_to_poly_uint64 (TYPE_SIZE (type)), ...) or so.

[Bug tree-optimization/98766] [10/11 Regression] SVE: ICE in tree_to_shwi with -O3 --param=avoid-fma-max-bits

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98766

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED

--- Comment #3 from ktkachov at gcc dot gnu.org ---
Patch posted at
https://gcc.gnu.org/pipermail/gcc-patches/2021-January/564082.html

[Bug tree-optimization/98766] [10/11 Regression] SVE: ICE in tree_to_shwi with -O3 --param=avoid-fma-max-bits

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98766

--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Kyrylo Tkachov <ktkachov@gcc.gnu.org>:

https://gcc.gnu.org/g:9d33785f57daf29dc0c106c919da319fe1906bc6

commit r11-6861-g9d33785f57daf29dc0c106c919da319fe1906bc6
Author: Kyrylo Tkachov <kyrylo.tkachov@arm.com>
Date:   Thu Jan 21 16:33:49 2021 +0000

    tree-ssa-mathopts: Use proper poly_int64 comparison with
param_avoid_fma_max_bits [PR 98766]

    We ICE here because we end up comparing a poly_int64 with a scalar using
    <= rather than maybe_le.
    This patch fixes that in the way rich suggests in the PR.

    gcc/ChangeLog:

            PR tree-optimization/98766
            * tree-ssa-math-opts.c (convert_mult_to_fma): Use maybe_le when
            comparing against type size with param_avoid_fma_max_bits.

    gcc/testsuite/ChangeLog:

            PR tree-optimization/98766
            * gcc.dg/pr98766.c: New test.

[Bug tree-optimization/98766] [10 Regression] SVE: ICE in tree_to_shwi with -O3 --param=avoid-fma-max-bits

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98766

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[10/11 Regression] SVE: ICE |[10 Regression] SVE: ICE in
                   |in tree_to_shwi with -O3    |tree_to_shwi with -O3
                   |--param=avoid-fma-max-bits  |--param=avoid-fma-max-bits

--- Comment #5 from ktkachov at gcc dot gnu.org ---
Fixed for GCC 11.

[Bug tree-optimization/98766] [10 Regression] SVE: ICE in tree_to_shwi with -O3 --param=avoid-fma-max-bits

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98766

--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-10 branch has been updated by Kyrylo Tkachov
<ktkachov@gcc.gnu.org>:

https://gcc.gnu.org/g:e753db89ddcc7f005fd54f861375bcdc85f23335

commit r10-9305-ge753db89ddcc7f005fd54f861375bcdc85f23335
Author: Kyrylo Tkachov <kyrylo.tkachov@arm.com>
Date:   Thu Jan 21 16:33:49 2021 +0000

    tree-ssa-mathopts: Use proper poly_int64 comparison with
param_avoid_fma_max_bits [PR 98766]

    We ICE here because we end up comparing a poly_int64 with a scalar using
    <= rather than maybe_le.
    This patch fixes that in the way rich suggests in the PR.

    gcc/ChangeLog:

            PR tree-optimization/98766
            * tree-ssa-math-opts.c (convert_mult_to_fma): Use maybe_le when
            comparing against type size with param_avoid_fma_max_bits.

    gcc/testsuite/ChangeLog:

            PR tree-optimization/98766
            * gcc.dg/pr98766.c: New test.

    (cherry picked from commit 9d33785f57daf29dc0c106c919da319fe1906bc6)

[Bug tree-optimization/98766] [10 Regression] SVE: ICE in tree_to_shwi with -O3 --param=avoid-fma-max-bits

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98766

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED
      Known to fail|11.0                        |

--- Comment #7 from ktkachov at gcc dot gnu.org ---
Fixed on branch too.