fNToRecFN

in hardfloat_sys

extern entity fNToRecFN<
    #uint intWidth,
    #uint expWidth,
    #uint sigWidth
>(
    control: uint<1>,
    signedIn: bool,
    in: uint<intWidth>,
    roundingMode: uint<3>,
    out: inv &uint<{expWidth + sigWidth + 1}>,
    exceptionFlags: inv &uint<5>
);

Description taken from the Berkeley Hardfloat documentation:

Converts from standard format into HardFloat’s equivalent recoded format.