x25519_ge_p1p1_to_p2
x25519_ge_p1p1_to_p2(&Ai_p2[i + 1], &t);
x25519_ge_p1p1_to_p2(r, &t);
x25519_ge_p1p1_to_p2(r, &t);
x25519_ge_p1p1_to_p2(r, &t);
x25519_ge_p1p1_to_p2(r, &t);
x25519_ge_p1p1_to_p2(&Pmasked_proj, &Pmasked);
x25519_ge_p1p1_to_p2(&s, &r);
x25519_ge_p1p1_to_p2(&s, &r);
x25519_ge_p1p1_to_p2(&s, &r);
x25519_ge_p1p1_to_p2(&Ai_p2[i], &t);