void fpe_mul_c(fpe_t rop, const fpe_t op1, const fpe_t op2)
{
mydouble h[24];
polymul(h,op1->v,op2->v);
degred(h);
coeffred_round_par(h);
int i;
for (i=0;i<12;i++)
rop->v[i] = h[i];
}
// Square an fp2e, store result in rop:
void fp2e_square_c(fp2e_t rop, const fp2e_t op)
{
#ifdef N_OPS
sqfp2ctr += 1;
#endif
fpe_t a1, b1, r1, r2;
mydouble ropa[24], ropb[24];
fp2e_to_2fpe(a1, b1, op);
int i;
/* CheckDoubles are not smart enough to recognize
* binomial formula to compute b^2-a^2 */
#ifdef CHECK
mydouble d1[24];
polymul(d1, a1->v, a1->v);
polymul(ropb, b1->v, b1->v);
polymul(ropa, b1->v, a1->v);
for (i = 0; i < 23; i++) {
ropb[i] -= d1[i];
ropa[i] *= 2;
}
#else
fpe_t t1, t2, t3;
for (i = 0; i < 12; i++) {
t1->v[i] = a1->v[i] + b1->v[i];
t2->v[i] = b1->v[i] - a1->v[i];
t3->v[i] = 2 * b1->v[i];
}
polymul(ropa, a1->v, t3->v);
polymul(ropb, t1->v, t2->v);
#endif
degred(ropa);
degred(ropb);
coeffred_round_par(ropa);
coeffred_round_par(ropb);
fpe_set_doublearray(r1, ropa);
fpe_set_doublearray(r2, ropb);
_2fpe_to_fp2e(rop, r1, r2);
}
// Multiply two fp2e, store result in rop:
void fp2e_mul_c(fp2e_t rop, const fp2e_t op1, const fp2e_t op2)
{
#ifdef N_OPS
mulfp2ctr += 1;
#endif
fpe_t a1, b1, a2, b2, r1, r2;
mydouble a3[24], b3[24];
int i;
mydouble t0[24], t1[24], t2[24], t3[24];
fp2e_to_2fpe(a1, b1, op1);
fp2e_to_2fpe(a2, b2, op2);
polymul(t1, a1->v, b2->v); // t1 = a1*b2
polymul(t2, b1->v, a2->v); // t2 = b1*a2
for (i = 0; i < 12; i++) // t3 = 1*a1
{
t3[i] = 1 * a1->v[i];
}
polymul(t3, t3, a2->v); // t3 = 1*a1*a2
polymul(t0, b1->v, b2->v); // t0 = b1*b2
for (i = 0; i < 23; i++) {
a3[i] = t1[i] + t2[i]; // a3 = a1*b2 + b1*a2
b3[i] = t0[i] - t3[i]; // b3 = b1*b2 - 1*a1*a2
}
degred(a3);
degred(b3);
coeffred_round_par(a3);
coeffred_round_par(b3);
fpe_set_doublearray(r1, a3);
fpe_set_doublearray(r2, b3);
_2fpe_to_fp2e(rop, r1, r2);
}