selfAddHiLo method
Implementation
DD selfAddHiLo(double yhi, double ylo) {
double H, h, T, t, S, s, e, f;
S = hi + yhi;
T = lo + ylo;
e = S - hi;
f = T - lo;
s = S - e;
t = T - f;
s = (yhi - e) + (hi - s);
t = (ylo - f) + (lo - t);
e = s + T;
H = S + e;
h = e + (S - H);
e = t + h;
double zhi = H + e;
double zlo = e + (H - zhi);
hi = zhi;
lo = zlo;
return this;
}