Module hash 

Karp-Rabin rolling hash (Karp & Rabin 1987; Section 2.1.3).

Polynomial fingerprints over the Mersenne prime 2^61-1. Full 61-bit fingerprints are used for collision-free seed comparison; fp_to_index maps them into the bounded hash table via F mod q.

Structs

RollingHash

Rolling hash for O(1) incremental fingerprint updates.

Functions

crc64_xz

Compute CRC-64/XZ of data; returns 8 bytes big-endian.

fingerprint

Compute the Karp-Rabin fingerprint of data[offset..offset+p] (Eq. 1, Section 2.1.3).

fp_to_index

Map a full fingerprint to a hash table index (F mod q, Section 2.1.3).

is_prime

Deterministic Miller-Rabin primality test.

mod_mersenne

Reduce a u128 value modulo the Mersenne prime 2^61-1.

next_prime

Smallest prime >= n.

precompute_bp

Precompute HASH_BASE^{p-1} mod HASH_MOD.