[Bug tree-optimization/108314] New: [13 Regression] Segfault in gimple-match-head.cc:do_valueize when vectorizing for SVE

["acoplan at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108314

            Bug ID: 108314
           Summary: [13 Regression] Segfault in
                    gimple-match-head.cc:do_valueize when vectorizing for
                    SVE
           Product: gcc
           Version: 12.0
            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 appears to be a regression on the trunk:

$ cat t.c
int x, y, z;
void f(void) {
  int t = 4;
  for (; x; x++) {
    if (y)
      continue;
    t = 0;
  }
  z = t;
}
$ aarch64-none-elf-gcc -c t.c -O2 -march=armv9-a
during GIMPLE pass: vect
t.c: In function 'f':
t.c:2:6: internal compiler error: Segmentation fault
    2 | void f(void) {
      |      ^
0xed3a4f crash_signal
        /home/alecop01/toolchain/src/gcc/gcc/toplev.cc:314
0x17255c4 do_valueize
        /home/alecop01/toolchain/src/gcc/gcc/gimple-match-head.cc:845
0x17255c4 operator()
        /home/alecop01/toolchain/src/gcc/gcc/gimple-match-head.cc:1071
0x17255c4 gimple_extract<gimple_simplify(gimple*, gimple_match_op*, gimple**,
tree_node* (*)(tree), tree_node* (*)(tree))::<lambda(tree)>,
gimple_simplify(gimple*, gimple_match_op*, gimple**, tree_node* (*)(tree),
tree_node* (*)(tree))::<lambda(tree)> >
        /home/alecop01/toolchain/src/gcc/gcc/gimple-match-head.cc:1028
0x17255c4 gimple_simplify(gimple*, gimple_match_op*, gimple**, tree_node*
(*)(tree_node*), tree_node* (*)(tree_node*))
        /home/alecop01/toolchain/src/gcc/gcc/gimple-match-head.cc:1103
0xb239b6 gimple_fold_stmt_to_constant_1(gimple*, tree_node* (*)(tree_node*),
tree_node* (*)(tree_node*))
        /home/alecop01/toolchain/src/gcc/gcc/gimple-fold.cc:7441
0x113d196 visit_stmt
        /home/alecop01/toolchain/src/gcc/gcc/tree-ssa-sccvn.cc:6134
0x113dcee process_bb
        /home/alecop01/toolchain/src/gcc/gcc/tree-ssa-sccvn.cc:7844
0x1140b4d do_rpo_vn_1
        /home/alecop01/toolchain/src/gcc/gcc/tree-ssa-sccvn.cc:8443
0x114127c do_rpo_vn(function*, edge_def*, bitmap_head*, bool, bool,
vn_lookup_kind)
        /home/alecop01/toolchain/src/gcc/gcc/tree-ssa-sccvn.cc:8545
0x123c0ce execute
        /home/alecop01/toolchain/src/gcc/gcc/tree-vectorizer.cc:1388
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