remove duplication

src/kem/kyber/common/reduce.h

@@ -0,0 +1,22 @@
+#ifndef KYBER_REDUCE_H
+#define KYBER_REDUCE_H
+
+#include <stdint.h>
+
+// TODO: Remove those once not used
+#define PQCLEAN_KYBER512_CLEAN_montgomery_reduce kyber_montgomery_reduce
+#define PQCLEAN_KYBER768_CLEAN_montgomery_reduce kyber_montgomery_reduce
+#define PQCLEAN_KYBER1024_CLEAN_montgomery_reduce kyber_montgomery_reduce
+
+#define PQCLEAN_KYBER512_CLEAN_barrett_reduce kyber_barrett_reduce
+#define PQCLEAN_KYBER768_CLEAN_barrett_reduce kyber_barrett_reduce
+#define PQCLEAN_KYBER1024_CLEAN_barrett_reduce kyber_barrett_reduce
+
+#define MONT 2285 // 2^16 mod q
+#define QINV 62209 // q^-1 mod 2^16
+
+int16_t kyber_montgomery_reduce(int32_t a);
+
+int16_t kyber_barrett_reduce(int16_t a);
+
+#endif