--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/config/bpf/constraints.md	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,32 @@
+;; Constraint definitions for eBPF.
+;; Copyright (C) 2019-2020 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_constraint "I"
+  "A 32-bit signed immediate."
+  (and (match_code "const_int")
+       (match_test "IN_RANGE (ival, -1 - 0x7fffffff, 0x7fffffff)")))
+
+(define_constraint "B"
+  "A constant argument for LDDW."
+  (match_code "const,symbol_ref,label_ref,const_double,const_int"))
+
+(define_constraint "S"
+  "A constant call address."
+  (match_code "const,symbol_ref,label_ref,const_int"))
+