mn10300: Implement adddi3, subdi3.

Via expander, pre- and post-reload patterns.  The pre-reload
pattern is defined to allow lower_subregs totally split the
DImode values.

From-SVN: r169014

gcc/ChangeLog

 2011-01-19  Richard Henderson  <rth@redhat.com>
 
+	* config/mn10300/mn10300.md (addsi3_flags): New.
+	(addc_internal, adddi3, adddi3_internal, *adddi3_degenerate): New.
+	(subsi3_flags, subc_internal, subdi3): New.
+	(subdi3_internal, *subdi3_degenerate): New.
+	* config/mn10300/predicates.md (reg_or_am33_const_operand): New.
+
 	* config/mn10300/mn10300.c (mn10300_can_use_retf_insn): New.
 	(mn10300_can_use_rets_insn): Rename from mn10300_can_use_return_insn.
 	(mn10300_expand_epilogue): Use it.  Compute REG_SAVE_BYTES once.

gcc/config/mn10300/predicates.md

@@ -43,6 +43,11 @@
       || XEXP (op, 1) == stack_pointer_rtx;
 })
 
+(define_predicate "reg_or_am33_const_operand"
+  (ior (match_operand 0 "register_operand")
+       (and (match_test "TARGET_AM33")
+	    (match_operand 0 "immediate_operand"))))
+
 (define_predicate "label_ref_operand"
   (match_code "label_ref"))