optabs.c (expand_binop): Pass INT_MODE to operand_subword_force iff the operand is a constant.

	* optabs.c (expand_binop): Pass INT_MODE to operand_subword_force
	iff the operand is a constant.

	* gcc.c-torture/compile/20181114.c: New test.

2018-11-14  Ilya Leoshkevich  <iii@linux.ibm.com>

From-SVN: r266151

gcc/ChangeLog

+2018-11-14  Jeff Law  <law@redhat.com>
+
+	* optabs.c (expand_binop): Pass INT_MODE to operand_subword_force
+	iff the operand is a constant.
+
 2018-11-14  Aldy Hernandez  <aldyh@redhat.com>
 
 	* gimple-ssa-evrp-analyze.c

gcc/optabs.c

@@ -1377,12 +1377,14 @@ expand_binop (machine_mode mode, optab binoptab, rtx op0, rtx op1,
       start_sequence ();
 
       /* Do the actual arithmetic.  */
+      enum machine_mode op0_mode = CONSTANT_P (op0) ? int_mode : VOIDmode;
+      enum machine_mode op1_mode = CONSTANT_P (op1) ? int_mode : VOIDmode;
       for (i = 0; i < GET_MODE_BITSIZE (int_mode) / BITS_PER_WORD; i++)
 	{
 	  rtx target_piece = operand_subword (target, i, 1, int_mode);
 	  rtx x = expand_binop (word_mode, binoptab,
-				operand_subword_force (op0, i, int_mode),
-				operand_subword_force (op1, i, int_mode),
+				operand_subword_force (op0, i, op0_mode),
+				operand_subword_force (op1, i, op1_mode),
 				target_piece, unsignedp, next_methods);
 
 	  if (x == 0)

gcc/testsuite/ChangeLog

+2018-11-14  Jeff Law  <law@redhat.com>
+
+	* gcc.c-torture/compile/20181114.c: New test.
+
 2018-11-14  Richard Biener  <rguenther@suse.de>
 
 	PR middle-end/87985

gcc/testsuite/gcc.c-torture/compile/20181114-1.c

+int
+_vfprintf_r (double fp)
+{
+  if (__builtin_signbit (fp))
+    return '-';
+}