Reference

Q_GFABSVAL(3)

fixed-point math functions which manipulate the fractional data bits

Part of Q_FRAWMASK(3).

NAME

Q_FRAWMASK, Q_GFRAW, Q_GFABSVAL, Q_GFVAL, Q_SFVAL – fixed-point math functions which manipulate the fractional data bits

SYNOPSIS

#include <sys/qmath.h>

ITYPE

Q_FRAWMASK(QTYPE q);

ITYPE

Q_GFRAW(QTYPE q);

ITYPE

Q_GFABSVAL(QTYPE q);

ITYPE

Q_GFVAL(QTYPE q);

QTYPE

Q_SFVAL(QTYPE q, ITYPE fv);

DESCRIPTION

Q_FRAWMASK() returns a q-specific bit mask for q's fractional data bits.

Q_GFRAW() returns q's raw masked fractional data bits.

Q_GFABSVAL() and Q_GFVAL() return the absolute and real values of q's fractional data bits respectively.

Q_SFVAL() sets q's fractional data bits to the value fv.

All of those functions operate on the following data types: s8q_t, u8q_t, s16q_t, u16q_t, s32q_t, u32q_t, s64q_t, and u64q_t, which are referred to generically as QTYPE. The ITYPE refers to the stdint(7) integer types.

For more details, see qmath(3).

RETURN VALUES

Q_FRAWMASK(), Q_GFRAW(), Q_GFABSVAL() and Q_GFVAL() return their respective values as integers of the same underlying ITYPE as q.

Q_SFVAL() returns the value of q post set.

SEE ALSO

errno(2), qmath(3), stdint(7)

HISTORY

The qmath(3) functions first appeared in FreeBSD 13.0.

AUTHORS

The qmath(3) functions and this manual page were written by Lawrence Stewart ⟨[email protected]⟩ and sponsored by Netflix, Inc.

History