--- /dev/null
+/* Copyright (c) 2016 Cryptography Research, Inc.
+ * Released under the MIT License. See LICENSE.txt for license information.
+ */
+
+#ifndef __ARCH_REF64_ARCH_INTRINSICS_H__
+#define __ARCH_REF64_ARCH_INTRINSICS_H__
+
+#define ARCH_WORD_BITS 64
+
+static __inline__ __attribute((always_inline,unused))
+uint64_t word_is_zero(uint64_t a) {
+ /* let's hope the compiler isn't clever enough to optimize this. */
+ return (((__uint128_t)a)-1)>>64;
+}
+
+static __inline__ __attribute((always_inline,unused))
+__uint128_t widemul(uint64_t a, uint64_t b) {
+ return ((__uint128_t)a) * b;
+}
+
+#endif /* ARCH_REF64_ARCH_INTRINSICS_H__ */
+