Just a suggestion, have you looked at the MPFR project, and derivatives: https://www.mpfr.org/ https://www.mpfr.org/ http://mpfr.loria.fr/mpfr-current/mpfr.htm

Just a suggestion, have you looked at the MPFR project, and derivatives: https://www.mpfr.org/ https://www.mpfr.org/ http://mpfr.loria.fr/mpfr-current/mpfr.html#index-mpfr_005fsubnormalize http://mpfr.loria.fr/mpfr-current/mpfr.html#index-mpfr_005fs... It is way to deep in the grubby details for my pay grade, but who knows?