[Bug tree-optimization/27093] [4.2 Regression] verify_ssa failed: definition does not dominate use

[rguenth at gcc dot gnu dot org]

------- Comment #3 from rguenth at gcc dot gnu dot org  2006-05-02 08:04 -------
    VRP causes the definition for SMT.5_37 to vanish, but it doesn't update the
PHI node.  After reassoc we have:


      # SMT.5_26 = PHI <SMT.5_35(4), SMT.5_43(7), SMT.5_41(5)>;
      # bytes_left_22 = PHI <bytes_left_34(4), bytes_left_42(7),
bytes_left_40(5)>;
      # seen_numbers_1 = PHI <0B(4), seen_numbers_15(7), seen_numbers_15(5)>;
    <L8>:;
      #   bytes_left_36 = V_MAY_DEF <bytes_left_22>;
      #   SMT.5_37 = V_MAY_DEF <SMT.5_26>;
      t1 ();
      if (seen_numbers_1 == 0B) goto <L0>; else goto <L1>;

    Invalid sum of incoming frequencies 9051, should be 8714
      # SMT.5_20 = PHI <SMT.5_37(8), SMT.5_31(2), SMT.5_35(3)>;
      # bytes_left_16 = PHI <bytes_left_36(8), bytes_left_30(2),
bytes_left_34(3)>;
    <L0>:;
      #   bytes_left_32 = V_MAY_DEF <bytes_left_16>;
      #   SMT.5_33 = V_MAY_DEF <SMT.5_20>;
      t1 ();

    while after VRP, the def for SMT.5_37 vanished:

      # SMT.5_26 = PHI <SMT.5_35(4), SMT.5_43(7), SMT.5_41(5)>;
      # bytes_left_22 = PHI <bytes_left_34(4), bytes_left_42(7),
bytes_left_40(5)>;
      # seen_numbers_1 = PHI <0B(4), seen_numbers_15(7), seen_numbers_15(5)>;
    <L8>:;
      #   bytes_left_36 = V_MAY_DEF <bytes_left_22>;
      t1 ();
      if (seen_numbers_1 == 0B) goto <L0>; else goto <L1>;

    Invalid sum of incoming frequencies 9051, should be 8714
      # SMT.5_20 = PHI <SMT.5_37(8), SMT.5_31(2), SMT.5_35(3)>;
      # bytes_left_16 = PHI <bytes_left_36(8), bytes_left_30(2),
bytes_left_34(3)>;
    <L0>:;
      #   bytes_left_32 = V_MAY_DEF <bytes_left_16>;
      t1 ();

    but we didn't update the PHI node.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27093