[Bug tree-optimization/105770] New: [13 Regression] ICE in decompose, at wide-int.h:984

[Bug tree-optimization/105770] New: [13 Regression] ICE in decompose, at wide-int.h:984

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105770

            Bug ID: 105770
           Summary: [13 Regression] ICE in decompose, at wide-int.h:984
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

gcc 13.0.0 20220529 snapshot (g:58a40e76ebadce78639644cd3d56e42b68336927) ICEs
when compiling the following testcase, reduced from
gcc/testsuite/gcc.dg/analyzer/pr103892.c, w/ -O1 -funswitch-loops
-fno-tree-forwprop:

char argstr;

void
argstr_get_word (void)
{
  while (argstr)
    switch (argstr)
      {
      case ' ':
      case '\t':
        return;
      }

  __builtin_unreachable ();
}

% gcc-13.0.0 -O1 -funswitch-loops -fno-tree-forwprop -c hlkdlkuv.c
during GIMPLE pass: unswitch
hlkdlkuv.c: In function 'argstr_get_word':
hlkdlkuv.c:4:1: internal compiler error: in decompose, at wide-int.h:984
    4 | argstr_get_word (void)
      | ^~~~~~~~~~~~~~~
0x7e7cea wi::int_traits<generic_wide_int<wide_int_ref_storage<false, false> >
>::decompose(long*, unsigned int, generic_wide_int<wide_int_ref_storage<false,
false> > const&)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/gcc-13-20220529/gcc/wide-int.h:984
0x7ec593 wi::int_traits<generic_wide_int<wide_int_storage> >::decompose(long*,
unsigned int, generic_wide_int<wide_int_storage> const&)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/gcc-13-20220529/gcc/tree.h:3701
0x7ec593 wide_int_ref_storage<true,
false>::wide_int_ref_storage<generic_wide_int<wide_int_storage>
>(generic_wide_int<wide_int_storage> const&, unsigned int)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/gcc-13-20220529/gcc/wide-int.h:1034
0x7ec593 generic_wide_int<wide_int_ref_storage<true, false>
>::generic_wide_int<generic_wide_int<wide_int_storage>
>(generic_wide_int<wide_int_storage> const&, unsigned int)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/gcc-13-20220529/gcc/wide-int.h:790
0x7ec593 wi::binary_traits<generic_wide_int<wide_int_ref_storage<false, false>
>, generic_wide_int<wide_int_storage>,
wi::int_traits<generic_wide_int<wide_int_ref_storage<false, false> >
>::precision_type, wi::int_traits<generic_wide_int<wide_int_storage>
>::precision_type>::result_type
wi::bit_and_not<generic_wide_int<wide_int_ref_storage<false, false> >,
generic_wide_int<wide_int_storage>
>(generic_wide_int<wide_int_ref_storage<false, false> > const&,
generic_wide_int<wide_int_storage> const&)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/gcc-13-20220529/gcc/wide-int.h:2343
0x7ec593 generic_simplify_111
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/build/gcc/generic-match.cc:8192
0x169139f generic_simplify_EQ_EXPR
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/build/gcc/generic-match.cc:56962
0xb44402 fold_binary_loc(unsigned int, tree_code, tree_node*, tree_node*,
tree_node*)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/gcc-13-20220529/gcc/fold-const.cc:10902
0xb4cdda fold_build2_loc(unsigned int, tree_code, tree_node*, tree_node*,
tree_node*)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/gcc-13-20220529/gcc/fold-const.cc:13854
0x1071bb3 find_unswitching_predicates_for_bb
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/gcc-13-20220529/gcc/tree-ssa-loop-unswitch.cc:537
0x1075b19 init_loop_unswitch_info
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/gcc-13-20220529/gcc/tree-ssa-loop-unswitch.cc:268
0x1075b19 tree_ssa_unswitch_loops(function*)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220529/work/gcc-13-20220529/gcc/tree-ssa-loop-unswitch.cc:332

[Bug tree-optimization/105770] [13 Regression] ICE in decompose, at wide-int.h:984

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105770

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2022-05-30

[Bug tree-optimization/105770] [13 Regression] ICE in decompose, at wide-int.h:984 since r13-754

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105770

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |13.0
            Summary|[13 Regression] ICE in      |[13 Regression] ICE in
                   |decompose, at               |decompose, at
                   |wide-int.h:984              |wide-int.h:984 since
                   |                            |r13-754
           Priority|P3                          |P1

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Started with r13-754-ga1c9f779f75283427316b5c670c1e01ff8ce9ced
--- gcc/tree-ssa-loop-unswitch.cc.jj    2022-05-25 11:07:29.754185772 +0200
+++ gcc/tree-ssa-loop-unswitch.cc       2022-05-30 10:57:23.165131441 +0200
@@ -494,6 +494,7 @@ find_unswitching_predicates_for_bb (basi
     {
       unsigned nlabels = gimple_switch_num_labels (stmt);
       tree idx = gimple_switch_index (stmt);
+      tree idx_type = TREE_TYPE (idx);
       if (TREE_CODE (idx) != SSA_NAME
          || nlabels < 1)
        return;
@@ -526,16 +527,18 @@ find_unswitching_predicates_for_bb (basi
          if (CASE_HIGH (lab) != NULL_TREE)
            {
              tree cmp1 = fold_build2 (GE_EXPR, boolean_type_node, idx,
-                                      CASE_LOW (lab));
+                                      fold_convert (idx_type,
+                                                    CASE_LOW (lab)));
              tree cmp2 = fold_build2 (LE_EXPR, boolean_type_node, idx,
-                                      CASE_HIGH (lab));
+                                      fold_convert (idx_type,
+                                                    CASE_HIGH (lab)));
              cmp = fold_build2 (BIT_AND_EXPR, boolean_type_node, cmp1, cmp2);
              lab_range.set (CASE_LOW (lab), CASE_HIGH (lab));
            }
          else
            {
              cmp = fold_build2 (EQ_EXPR, boolean_type_node, idx,
-                                CASE_LOW (lab));
+                                fold_convert (idx_type, CASE_LOW (lab)));
              lab_range.set (CASE_LOW (lab));
            }

fixes it for me.

[Bug tree-optimization/105770] [13 Regression] ICE in decompose, at wide-int.h:984 since r13-754

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105770

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 53052
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53052&action=edit
gcc13-pr105770.patch

Full untested patch.

[Bug tree-optimization/105770] [13 Regression] ICE in decompose, at wide-int.h:984 since r13-754

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105770

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
LGTM - IIRC at some point we required the case labels to have compatible types
to the index, didn't we?

[Bug tree-optimization/105770] [13 Regression] ICE in decompose, at wide-int.h:984 since r13-754

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105770

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I think all the case labels are required to have the same types, but the index
can be promoted (such as in this case promotion from char to int).  I've looked
at other switch handling cases and they do such conversions there.

[Bug tree-optimization/105770] [13 Regression] ICE in decompose, at wide-int.h:984 since r13-754

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105770

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

https://gcc.gnu.org/g:0d5cc976a36af07c9790c38a99a0b98110c89795

commit r13-912-g0d5cc976a36af07c9790c38a99a0b98110c89795
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Wed Jun 1 14:00:49 2022 +0200

    unswitch: Fold case label lo/hi values to index type [PR105770]

    The following testcase ICEs because we use different types in comparison,
    idx has int type, while CASE_LOW has char type.

    While I believe all CASE_{LOW,HIGH} in the same switch have to use the same
    or compatible type, the index expression can have a promoted type as
happens
    in this testcase.  Other spots that handle switches do such foldings too.

    2022-06-01  Jakub Jelinek  <jakub@redhat.com>

            PR tree-optimization/105770
            * tree-ssa-loop-unswitch.cc (find_unswitching_predicates_for_bb):
Cast
            CASE_LOW and CASE_HIGH to TREE_TYPE (idx) before comparisons with
idx.

            * gcc.dg/pr105770.c: New test.

[Bug tree-optimization/105770] [13 Regression] ICE in decompose, at wide-int.h:984 since r13-754

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105770

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

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

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed.