[Bug tree-optimization/101026] New: [12 Regression] ICE Segmentation fault since r12-1329-gce670e4faafb296d

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101026

            Bug ID: 101026
           Summary: [12 Regression] ICE Segmentation fault since
                    r12-1329-gce670e4faafb296d
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
                CC: rguenth at gcc dot gnu.org
  Target Milestone: ---

The following fails:

$ cat ice.f
      SUBROUTINE PASSB4 (CC,CH)
      DIMENSION CC(IDO,4,L1), CH(IDO,L1,*)
         DO 103 I=2,IDO,2
            TI4 = CC0-CC(I,4,K)
            CI4 = TI1-TI4
            CH(I-1,K,4) = CI4
            CH(I,K,4) = CI4
  103    CONTINUE
      END

$ gcc ice.f -Ofast -c -frounding-math 
during GIMPLE pass: vect
ice.f:1:23:

    1 |       SUBROUTINE PASSB4 (CC,CH)
      |                       ^
internal compiler error: Segmentation fault
0xf15eda crash_signal
        /home/marxin/Programming/gcc/gcc/toplev.c:327
0x7ffff786239f ???
        ../sysdeps/unix/sysv/linux/sigaction.c:10
0x11d40e2 vect_optimize_slp(vec_info*)
        /home/marxin/Programming/gcc/gcc/tree-vect-slp.c:3626
0x11b4f3e vect_analyze_loop_2
        /home/marxin/Programming/gcc/gcc/tree-vect-loop.c:2332
0x11b51fa vect_analyze_loop(loop*, vec_info_shared*)
        /home/marxin/Programming/gcc/gcc/tree-vect-loop.c:2986
0x11e6615 try_vectorize_loop_1
        /home/marxin/Programming/gcc/gcc/tree-vectorizer.c:1009
0x11e704e vectorize_loops()
        /home/marxin/Programming/gcc/gcc/tree-vectorizer.c:1243
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