Fix comparison mode in simplify_ternary_operation

2017-11-20  Tom de Vries  <tom@codesourcery.com>

	PR rtl-optimization/82020
	* simplify-rtx.c (simplify_ternary_operation): Fix comparison mode of
	IF_THEN_ELSE condition.

From-SVN: r254944

gcc/ChangeLog

+2017-11-20  Tom de Vries  <tom@codesourcery.com>
+
+	PR rtl-optimization/82020
+	* simplify-rtx.c (simplify_ternary_operation): Fix comparison mode of
+	IF_THEN_ELSE condition.
+
 2017-11-19  Jeff Law  <law@redhat.com>
 
 	* tree-ssa-dom.c (record_equivalences_from_phis): Fix handling

gcc/simplify-rtx.c

@@ -5651,8 +5651,6 @@ simplify_ternary_operation (enum rtx_code code, machine_mode mode,
 					      XEXP (op0, 0), XEXP (op0, 1));
 	    }
 
-	  if (cmp_mode == VOIDmode)
-	    cmp_mode = op0_mode;
 	  temp = simplify_relational_operation (GET_CODE (op0), op0_mode,
 			  			cmp_mode, XEXP (op0, 0),
 						XEXP (op0, 1));