felem_mul_reduce
felem_mul_reduce,
felem_mul_reduce(beta, x_in, gamma); /* beta[i] < 2^56 */
felem_mul_reduce(alpha, ftmp, ftmp2); /* alpha[i] < 2^56 */
felem_mul_reduce(ftmp3, x1, ftmp2); /* ftmp3[i] < 2^56 */
felem_mul_reduce(ftmp2, ftmp2, z2); /* ftmp2[i] < 2^56 */
felem_mul_reduce(ftmp6, y1, ftmp2); /* ftmp6[i] < 2^56 */
felem_mul_reduce(z_out, ftmp5, ftmp4); /* z_out[i] < 2^56 */
felem_mul_reduce(ftmp, ftmp, z1); /* ftmp[i] < 2^56 */
felem_mul_reduce(ftmp2, ftmp4, ftmp); /* ftmp2[i] < 2^56 */
felem_mul_reduce(ftmp4, ftmp3, ftmp); /* ftmp4[i] < 2^56 */
felem_mul_reduce,
felem_mul_reduce(ftmp, ftmp, in); /* 2^1 + 2^0 */
felem_mul_reduce(ftmp, ftmp, in); /* 2^2 + 2^1 * 2^0 */
felem_mul_reduce(ftmp, ftmp3, ftmp); /* 2^5 + 2^4 + 2^3 + 2^2 + 2^1 + 2^0 */
felem_mul_reduce(ftmp, ftmp4, ftmp); /* 2^11 + ... + 2^0 */
felem_mul_reduce(ftmp, ftmp3, ftmp); /* 2^14 + ... + 2^0 */
felem_mul_reduce(ftmp, ftmp5, ftmp); /* 2^29 + ... + 2^0 */
felem_mul_reduce(ftmp, ftmp6, ftmp); /* 2^59 + ... + 2^0 */
felem_mul_reduce(ftmp, ftmp4, ftmp); /* 2^119 + ... + 2^0 */
felem_mul_reduce(ftmp, ftmp4, ftmp); /* 2^239 + ... + 2^0 */
felem_mul_reduce(ftmp, ftmp5, ftmp); /* 2^254 + ... + 2^0 */
felem_mul_reduce(ftmp, ftmp6, ftmp); /* 2^285 + ... + 2^31 + 2^29 + ... + 2^0 */
felem_mul_reduce(ftmp, ftmp2, ftmp); /* 2^287 + ... + 2^33 + 2^31 + ... + 2^0 */
felem_mul_reduce(ftmp, ftmp6, ftmp); /* 2^381 + ... + 2^127 + 2^125 + ... + 2^94 + 2^29 + ... + 2^0 */
felem_mul_reduce(ftmp, in, ftmp); /* 2^383 + ... + 2^129 + 2^127 + ... + 2^96 + 2^31 + ... + 2^2 + 2^0 */
felem_mul_reduce,