[Bug tree-optimization/91896] New: [10 Regression] ICE in vect_get_vec_def_for_stmt_copy, at tree-vect-stmts.c:1687

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91896

            Bug ID: 91896
           Summary: [10 Regression] ICE in vect_get_vec_def_for_stmt_copy,
                    at tree-vect-stmts.c:1687
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Keywords: ice-on-invalid-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

gcc-10.0.0-alpha20190922 snapshot (r276031) ICEs when compiling the following
testcase w/ -O3:

unsigned int
zj (unsigned int et)
{
  signed char jr = 0;

  do {
    et *= 3;
    jr += 2;
  } while (jr >= 0);

  if (et == (unsigned int) jr)
    et = 0;

  return et;
}

% gcc-10.0.0-alpha20190922 -O3 -c tyrn8jdd.c
during GIMPLE pass: vect
tyrn8jdd.c: In function 'zj':
tyrn8jdd.c:2:1: internal compiler error: in vect_get_vec_def_for_stmt_copy, at
tree-vect-stmts.c:1687
    2 | zj (unsigned int et)
      | ^~
0x6fb09c vect_get_vec_def_for_stmt_copy(vec_info*, tree_node*)
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20190922/work/gcc-10-20190922/gcc/tree-vect-stmts.c:1687
0x6fb09c vect_get_vec_def_for_stmt_copy(vec_info*, tree_node*)
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20190922/work/gcc-10-20190922/gcc/tree-vect-stmts.c:1679
0xf95667 vect_get_vec_defs_for_stmt_copy(vec_info*, vec<tree_node*, va_heap,
vl_ptr>*, vec<tree_node*, va_heap, vl_ptr>*)
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20190922/work/gcc-10-20190922/gcc/tree-vect-stmts.c:1706
0xf9bd27 vectorizable_shift(_stmt_vec_info*, gimple_stmt_iterator*,
_stmt_vec_info**, _slp_tree*, vec<stmt_info_for_cost, va_heap, vl_ptr>*)
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20190922/work/gcc-10-20190922/gcc/tree-vect-stmts.c:5843
0xfb5609 vect_transform_stmt(_stmt_vec_info*, gimple_stmt_iterator*,
_slp_tree*, _slp_instance*)
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20190922/work/gcc-10-20190922/gcc/tree-vect-stmts.c:10755
0xfb72bc vect_transform_loop_stmt
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20190922/work/gcc-10-20190922/gcc/tree-vect-loop.c:8244
0xfbe9d8 vect_transform_loop(_loop_vec_info*)
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20190922/work/gcc-10-20190922/gcc/tree-vect-loop.c:8461
0xfe85e8 try_vectorize_loop_1
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20190922/work/gcc-10-20190922/gcc/tree-vectorizer.c:981
0xfe906a vectorize_loops()
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20190922/work/gcc-10-20190922/gcc/tree-vectorizer.c:1113