--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/config/mmix/constraints.md	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,116 @@
+;; MMIX constraints
+;; Copyright (C) 2012-2017 Free Software Foundation, Inc.
+;;
+;; This file is part of GCC.
+;;
+;; GCC is free software; you can redistribute it and/or modify it
+;; under the terms of the GNU General Public License as published by
+;; the Free Software Foundation; either version 3, or (at your option)
+;; any later version.
+;;
+;; GCC is distributed in the hope that it will be useful, but WITHOUT
+;; ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+;; or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+;; License for more details.
+;;
+;; You should have received a copy of the GNU General Public License
+;; along with GCC; see the file COPYING3.  If not see
+;; <http://www.gnu.org/licenses/>.  */
+
+(define_register_constraint "x" "SYSTEM_REGS"
+  "@internal")
+
+(define_register_constraint "y" "REMAINDER_REG"
+  "@internal")
+
+(define_register_constraint "z" "HIMULT_REG"
+  "@internal")
+
+(define_constraint "I"
+  "A 8-bit unsigned integer"
+  (and (match_code "const_int")
+       (match_test "IN_RANGE (ival, 0, 255)")))
+
+(define_constraint "J"
+  "A 16-bit unsigned integer."
+  (and (match_code "const_int")
+       (match_test "IN_RANGE (ival, 0, 65535)")))
+
+(define_constraint "K"
+  "An integer between -255 and 0."
+  (and (match_code "const_int")
+       (match_test "IN_RANGE (ival, -255, 0)")))
+
+(define_constraint "L"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "mmix_shiftable_wyde_value (ival)")))
+
+(define_constraint "M"
+  "The value 0."
+  (and (match_code "const_int")
+       (match_test "ival == 0")))
+
+(define_constraint "N"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "mmix_shiftable_wyde_value (~ival)")))
+
+(define_constraint "O"
+  "The value 3, 5, 9, or 17."
+  (and (match_code "const_int")
+       (ior (match_test "ival == 3")
+	    (match_test "ival == 5")
+	    (match_test "ival == 9")
+	    (match_test "ival == 17"))))
+
+;; FIXME: M (or G) is redundant.
+
+(define_constraint "G"
+  "Floating-point zero."
+  (and (match_code "const_double")
+       (match_test "op == CONST0_RTX (mode)")))
+
+;; R asks whether x is to be loaded with GETA or something else.  Right
+;; now, only a SYMBOL_REF and LABEL_REF can fit for
+;; TARGET_BASE_ADDRESSES.
+;;
+;; Only constant symbolic addresses apply.  With TARGET_BASE_ADDRESSES,
+;; we just allow straight LABEL_REF or SYMBOL_REFs with SYMBOL_REF_FLAG
+;; set right now; only function addresses and code labels.  If we change
+;; to let SYMBOL_REF_FLAG be set on other symbols, we have to check
+;; inside CONST expressions.  When TARGET_BASE_ADDRESSES is not in
+;; effect, a "raw" constant check together with mmix_constant_address_p
+;; is all that's needed; we want all constant addresses to be loaded
+;; with GETA then.
+
+(define_constraint "R"
+  "@internal"
+  (and (not (match_code "const_int,const_double"))
+       (match_test "mmix_constant_address_p (op)")
+       (ior (match_test "!TARGET_BASE_ADDRESSES")
+	    (match_code "label_ref")
+	    (and (match_code "symbol_ref")
+		 (match_test "SYMBOL_REF_FLAG (op)")))))
+
+;; FIXME: L (or S) is redundant.
+
+(define_constraint "S"
+  "@internal"
+  (and (match_code "const_int,const_double")
+       (match_test "mmix_shiftable_wyde_value (mmix_intval (op))")))
+
+;; FIXME: N (or T) is redundant.
+
+(define_constraint "T"
+  "@internal"
+  (and (match_code "const_int,const_double")
+       (match_test "mmix_shiftable_wyde_value (~mmix_intval (op))")))
+
+(define_address_constraint "U"
+  "@internal"
+  (match_operand 0 "mmix_address_operand"))
+
+(define_constraint "Yf"
+  "@internal"
+  (match_operand 0 "frame_pointer_operand"))