private static void ge_p3_to_cached(ref ge_cached r, ge_p3 p)
{
ReadOnlySpan <int> d2 = stackalloc int[] { -21827239, -5839606, -30745221, 13898782, 229458, 15978800, -12551817, -6495438, 29715968, 9444199 };
ge_cached result = new()
{
YminusX = stackalloc int[10],
YplusX = stackalloc int[10],
T2d = stackalloc int[10],
Z = stackalloc int[10],
};
r.YminusX.CopyTo(result.YminusX);
r.YplusX.CopyTo(result.YplusX);
r.T2d.CopyTo(result.T2d);
r.Z.CopyTo(result.Z);
fe_add(ref result.YplusX, p.Y, p.X);
fe_sub(ref result.YminusX, p.Y, p.X);
fe_copy(ref result.Z, p.Z);
fe_mul(ref result.T2d, p.T, d2);
result.YminusX.CopyTo(r.YminusX);
result.YplusX.CopyTo(r.YplusX);
result.T2d.CopyTo(r.T2d);
result.Z.CopyTo(r.Z);
}
private static void ge_sub(ref ge_p1p1 r, ge_p3 p, ge_cached q)
{
Span <int> t0 = stackalloc int[10];
ge_p1p1 result = new()
{
X = stackalloc int[10],
Y = stackalloc int[10],
Z = stackalloc int[10],
T = stackalloc int[10],
};
r.X.CopyTo(result.X);
r.Y.CopyTo(result.Y);
r.Z.CopyTo(result.Z);
r.T.CopyTo(result.T);
fe_add(ref result.X, p.Y, p.X);
fe_sub(ref result.Y, p.Y, p.X);
fe_mul(ref result.Z, result.X, q.YminusX);
fe_mul(ref result.Y, result.Y, q.YplusX);
fe_mul(ref result.T, q.T2d, p.T);
fe_mul(ref result.X, p.Z, q.Z);
fe_add(ref t0, result.X, result.X);
fe_sub(ref result.X, result.Z, result.Y);
fe_add(ref result.Y, result.Z, result.Y);
fe_sub(ref result.Z, t0, result.T);
fe_add(ref result.T, t0, result.T);
result.X.CopyTo(r.X);
result.Y.CopyTo(r.Y);
result.Z.CopyTo(r.Z);
result.T.CopyTo(r.T);
}
