Do not compute ||bk||^2 if not necessary.
Do not compute ||bk||^2 if not necessary.

cr-marcstevens/fplll,fplll/fplll,cr-marcstevens/fplll,dstehle/fplll,cr-marcstevens/fplll,dstehle/fplll,cr-marcstevens/fplll,fplll/fplll,fplll/fplll,fplll/fplll,dstehle/fplll,fplll/fplll