[Bug tree-optimization/59757] Unexpected VN_TOP in SSCVN

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59757

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
That is,

Index: gcc/tree-ssa-sccvn.c
===================================================================
--- gcc/tree-ssa-sccvn.c        (revision 206576)
+++ gcc/tree-ssa-sccvn.c        (working copy)
@@ -3605,6 +3605,7 @@ visit_use (tree use)
        changed = defs_to_varying (stmt);
     }
  done:
+  gcc_assert (!virtual_operand_p (use) || SSA_VAL (use) != VN_TOP);
   return changed;
 }

should help catching the bug.