public static void square(int[] x, int[] zz) {
Nat256.square(x, zz);
Nat256.square(x, 8, zz, 16);
int c24 = Nat256.addToEachOther(zz, 8, zz, 16);
int c16 = c24 + Nat256.addTo(zz, 0, zz, 8, 0);
c24 += Nat256.addTo(zz, 24, zz, 16, c16);
int[] dx = Nat256.create();
Nat256.diff(x, 8, x, 0, dx, 0);
int[] tt = Nat256.createExt();
Nat256.square(dx, tt);
c24 += Nat.subFrom(16, tt, 0, zz, 8);
Nat.addWordAt(32, c24, zz, 24);
}
public static void mul(int[] x, int[] y, int[] zz) {
Nat256.mul(x, y, zz);
Nat256.mul(x, 8, y, 8, zz, 16);
int c24 = Nat256.addToEachOther(zz, 8, zz, 16);
int c16 = c24 + Nat256.addTo(zz, 0, zz, 8, 0);
c24 += Nat256.addTo(zz, 24, zz, 16, c16);
int[] dx = Nat256.create(), dy = Nat256.create();
boolean neg = Nat256.diff(x, 8, x, 0, dx, 0) != Nat256.diff(y, 8, y, 0, dy, 0);
int[] tt = Nat256.createExt();
Nat256.mul(dx, dy, tt);
c24 += neg ? Nat.addTo(16, tt, 0, zz, 8) : Nat.subFrom(16, tt, 0, zz, 8);
Nat.addWordAt(32, c24, zz, 24);
}