ira.c (ira_get_dup_out_num): Check for output operands at the start of the loop.

gcc/
	* ira.c (ira_get_dup_out_num): Check for output operands at
	the start of the loop.  Handle cases where an included alternative
	follows an excluded one.

From-SVN: r211072

gcc/ChangeLog

+2014-05-30  Richard Sandiford  <rdsandiford@googlemail.com>
+
+	* ira.c (ira_get_dup_out_num): Check for output operands at
+	the start of the loop.  Handle cases where an included alternative
+	follows an excluded one.
+
 2014-05-29  Mike Stump  <mikestump@comcast.net>
 
 	PR debug/61352

gcc/ira.c

@@ -1979,33 +1979,33 @@ ira_get_dup_out_num (int op_num, HARD_REG_SET &alts)
 
   if (op_num < 0 || recog_data.n_alternatives == 0)
     return -1;
-  use_commut_op_p = false;
+  /* We should find duplications only for input operands.  */
+  if (recog_data.operand_type[op_num] != OP_IN)
+    return -1;
   str = recog_data.constraints[op_num];
+  use_commut_op_p = false;
   for (;;)
     {
 #ifdef EXTRA_CONSTRAINT_STR
       op = recog_data.operand[op_num];
 #endif
       
-      for (ignore_p = false, original = -1, curr_alt = 0;;)
+      for (curr_alt = 0, ignore_p = !TEST_HARD_REG_BIT (alts, curr_alt),
+	   original = -1;;)
 	{
 	  c = *str;
 	  if (c == '\0')
 	    break;
-	  if (c == '#' || !TEST_HARD_REG_BIT (alts, curr_alt))
+	  if (c == '#')
 	    ignore_p = true;
 	  else if (c == ',')
 	    {
 	      curr_alt++;
-	      ignore_p = false;
+	      ignore_p = !TEST_HARD_REG_BIT (alts, curr_alt);
 	    }
 	  else if (! ignore_p)
 	    switch (c)
 	      {
-		/* We should find duplications only for input operands.  */
-	      case '=':
-	      case '+':
-		goto fail;
 	      case 'X':
 	      case 'p':
 	      case 'g':