public static void Add(uint[] x, uint[] y, uint[] z)
{
Nat256.Add(x, y, z);
if (Nat256.Gte(z, P))
{
Nat256.AddWord(PInv, z, 0);
z[7] &= P7;
}
}
public static void Twice(uint[] x, uint[] z)
{
Nat256.ShiftUpBit(x, 0, z);
if (Nat256.Gte(z, P))
{
Nat256.AddWord(PInv, z, 0);
z[7] &= P7;
}
}
public static uint[] FromBigInteger(BigInteger x)
{
uint[] z = Nat256.FromBigInteger(x);
if (Nat256.Gte(z, P))
{
Nat256.AddWord(PInv, z, 0);
z[7] &= P7;
}
return(z);
}
public static void AddOne(uint[] x, uint[] z)
{
Nat256.Copy(x, z);
Nat256.Inc(z, 0);
if (Nat256.Gte(z, P))
{
Nat256.AddWord(PInv, z, 0);
z[7] &= P7;
}
}
public static void Reduce(uint[] xx, uint[] z)
{
Debug.Assert(xx[15] >> 30 == 0);
uint xx07 = xx[7];
Nat.ShiftUpBit(8, xx, 8, xx07, z);
uint c = Nat256.MulByWordAddTo(PInv, xx, z) << 1;
uint z07 = z[7];
z[7] = z07 & P7;
c += (z07 >> 31) - (xx07 >> 31);
Nat256.AddWord(c * PInv, z, 0);
if (Nat256.Gte(z, P))
{
Nat256.AddWord(PInv, z, 0);
z[7] &= P7;
}
}
