re PR middle-end/53245 (ice in expand_case)

	PR middle-end/53245
	* gimplify.c (preprocess_case_label_vec_for_gimple): If low or high
	is folded to a type boundary value, verify that the resulting case
	label is still a care range.

From-SVN: r187248

gcc/ChangeLog

+2012-05-07  Steven Bosscher  <steven@gcc.gnu.org>
+
+	PR middle-end/53245
+	* gimplify.c (preprocess_case_label_vec_for_gimple): If low or high
+	is folded to a type boundary value, verify that the resulting case
+	label is still a care range.
+
 2012-05-07  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/i386/i386.md (ctz<mode>2): Emit rep;bsf

gcc/gimplify.c

@@ -1658,6 +1658,10 @@ preprocess_case_label_vec_for_gimple (VEC(tree,heap) *labels,
 		      && tree_int_cst_compare (high, max_value) > 0)
 		    high = max_value;
 		  high = fold_convert (index_type, high);
+
+		  /* We may have folded a case range to a one-value case.  */
+		  if (tree_int_cst_equal (low, high))
+		    high = NULL_TREE;
 		}
 	    }