static private void Mul(BigNumber aa, BigNumber bb, BigNumber rr)
{
int ai, itmp, nexp, ii, jj, indexa, indexb, index0, numdigits;
sbyte sign;
sign = (sbyte)(aa.signum * bb.signum);
nexp = aa.exponent + bb.exponent;
if (sign == 0)
{
BigNumber.SetZero(rr);
return;
}
numdigits = aa.dataLength + bb.dataLength;
indexa = (aa.dataLength + 1) >> 1;
indexb = (bb.dataLength + 1) >> 1;
if (indexa >= 48 && indexb >= 48)
{
BigNumber.FastMul(aa, bb, rr);
return;
}
ii = (numdigits + 1) >> 1;
if (ii >= rr.mantissa.Length)
{
BigNumber.Expand(rr, ii + 32);
}
index0 = indexa + indexb;
for (int i = 0; i < index0; i++)
{
rr.mantissa[i] = 0;
}
ii = indexa;
while (true)
{
index0--;
int crp = index0;
jj = indexb;
ai = (int)aa.mantissa[--ii];
while (true)
{
itmp = ai * bb.mantissa[--jj];
rr.mantissa[crp - 1] += s_MsbLookupMult[itmp];
rr.mantissa[crp] += s_LsbLookupMult[itmp];
if (rr.mantissa[crp] >= 100)
{
rr.mantissa[crp] -= 100;
rr.mantissa[crp - 1] += 1;
}
crp--;
if (rr.mantissa[crp] >= 100)
{
rr.mantissa[crp] -= 100;
rr.mantissa[crp - 1] += 1;
}
if (jj == 0)
{
break;
}
}
if (ii == 0)
{
break;
}
}
rr.signum = sign;
rr.exponent = nexp;
rr.dataLength = numdigits;
BigNumber.Normalize(rr);
}