Not the GP, but in the sense that it can't be used to hash arbitrary (word-padded) data. This "hash" can only turn words into other words. A true hash function

Not the GP, but in the sense that it can't be used to hash arbitrary (word-padded) data. This "hash" can only turn words into other words. A true hash function needs to produce a hash from a multi-word buffer, and do so in a way that all the data in the buffer is equally significant to the final hash value.