compiling the attached testcase (reduced from tree.c) with -O2 leads to vrp
  if (D.2762_2 == 6)
    goto <bb 3>;
    goto <bb 9>;

<bb 3>:
  D.2766_5 = (int) D.2762_2;
  D.2767_6 = tree_code_type[D.2766_5];

  D.2762_2 = type_1(D)->base.code;
  if (D.2762_2 == 6)
    goto <bb 3>;
    goto <bb 9>;

<bb 3>:
  D.2766_5 = 6;
  D.2767_6 = tree_code_type[6];

this is good transform, however tree_code_type is constant initialized array
and we miss possibility to fold it into constant until expansion triggering
code in expr.c I would like to retire.

We can fold tree_code_type[6], so apparently just no one calls fold_gimple_stmt
on it?

           Summary: VRP misses oppurtunity for statement folding.
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: hubicka at gcc dot gnu dot org


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