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+ * Guest-side interface for instruction-based backdoor communication.
+ * Copyright (c) 2010 Lluís Vilanova <email@example.com>
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ * This library 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
+ * Lesser General Public License for more details.
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+/* Backdoor macro names define the types of its arguments:
+ * - i8: immediate of 8 bits
+ * - v32: value of 32 bits
+#error Undefined instruction-based backdoor interface for guest architecture
+#endif /* BACKDOOR__GUEST_H */