const rounds … // core applies the Salsa20 core function to 16-byte input in, 32-byte key k, // and 16-byte constant c, and puts the result into 64-byte array out. func core(out *[64]byte, in *[16]byte, k *[32]byte, c *[16]byte) { … } // genericXORKeyStream is the generic implementation of XORKeyStream to be used // when no assembly implementation is available. func genericXORKeyStream(out, in []byte, counter *[16]byte, key *[32]byte) { … }