C code for GF(2q) for q <64

This file provides and tests code for GF(2q) for 0<q<64. The irreducible polynomials for each q are tabulated in the array irrp. 2q+irrp[q] is that polynomial for 0<q<64. The values in irrp were provided by the 3 lines of Scheme code (in this context) at the end of the program.
pmul(L a, L b)
is the polynomial multiplication routine that is ignorant of the irp (irreducible polynomial).
fmul(L a, L b)
is the multiplication in GF(2q), i.e. the product modulo the irp. In this routine we deduct the irp after each multiplication step.
is merely a routine to locate the most significant bit.
PR pqr(L n, L d)
is synthetic division in the polynomial ring.
PR ge(L a, L b)
is the recursive extended Euclidean Algorithm for GF(2q). ge(a, b) returns (PR){x, y} such that ax+by = gcd(a, b).
returns a q bit random number.
finv(L x)
returns the multiplicative inverse in GF(2q).