tree-into-ssa.c (update_ssa): Verify we do not rename symbols that are already partly in SSA form.

2012-08-14  Richard Guenther  <rguenther@suse.de>

	* tree-into-ssa.c (update_ssa): Verify we do not rename
	symbols that are already partly in SSA form.

From-SVN: r190377

gcc/ChangeLog

+2012-08-14  Richard Guenther  <rguenther@suse.de>
+
+	* tree-into-ssa.c (update_ssa): Verify we do not rename
+	symbols that are already partly in SSA form.
+
 2012-08-14  Jakub Jelinek  <jakub@redhat.com>
 
 	PR middle-end/53411

gcc/tree-into-ssa.c

@@ -3247,6 +3247,30 @@ update_ssa (unsigned update_flags)
 	 statements and set local live-in information for the PHI
 	 placement heuristics.  */
       prepare_block_for_update (start_bb, insert_phi_p);
+
+#ifdef ENABLE_CHECKING
+      for (i = 1; i < num_ssa_names; ++i)
+	{
+	  tree name = ssa_name (i);
+	  if (!name
+	      || virtual_operand_p (name))
+	    continue;
+
+	  /* For all but virtual operands, which do not have SSA names
+	     with overlapping life ranges, ensure that symbols marked
+	     for renaming do not have existing SSA names associated with
+	     them as we do not re-write them out-of-SSA before going
+	     into SSA for the remaining symbol uses.  */
+	  if (marked_for_renaming (SSA_NAME_VAR (name)))
+	    {
+	      fprintf (stderr, "Existing SSA name for symbol marked for "
+		       "renaming: ");
+	      print_generic_expr (stderr, name, TDF_SLIM);
+	      fprintf (stderr, "\n");
+	      internal_error ("SSA corruption");
+	    }
+	}
+#endif
     }
   else
     {