estimateDiv64To32
return ( ( estimateDiv64To32( a, 0, z ) )>>1 ) + ( z>>1 );
zSig = estimateDiv64To32( aSig, 0, bSig );
q = estimateDiv64To32( aSig, 0, bSig );
q = estimateDiv64To32( aSig, 0, bSig );
zSig0 = estimateDiv64To32( aSig0, aSig1, bSig0 );
zSig1 = estimateDiv64To32( rem1, rem2, bSig0 );
q = estimateDiv64To32( aSig0, aSig1, bSig0 );
q = estimateDiv64To32( aSig0, aSig1, bSig0 );
zSig1 = estimateDiv64To32( rem1, 0, doubleZSig0 );