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				.\" $FreeBSD$
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				.Dd July 8, 2018
				.Dt Q_SIGNSHFT 3
				.Os
				.Sh NAME
				.Nm Q_SIGNSHFT ,
				.Nm Q_SSIGN ,
				.Nm Q_CRAWMASK ,
				.Nm Q_SRAWMASK ,
				.Nm Q_GCRAW ,
				.Nm Q_GCVAL ,
				.Nm Q_SCVAL
				.Nd fixed-point math functions which manipulate the control/sign data bits
				.Sh SYNOPSIS
				.In sys/qmath.h
				.Ft uint32_t
				.Fn Q_SIGNSHFT "QTYPE q"
				.Ft QTYPE
				.Fn Q_SSIGN "QTYPE q" "bool isneg"
				.Ft ITYPE
				.Fn Q_CRAWMASK "QTYPE q"
				.Ft ITYPE
				.Fn Q_SRAWMASK "QTYPE q"
				.Ft ITYPE
				.Fn Q_GCRAW "QTYPE q"
				.Ft ITYPE
				.Fn Q_GCVAL "QTYPE q"
				.Ft QTYPE
				.Fn Q_SCVAL "QTYPE q" "ITYPE cv"
				.Sh DESCRIPTION
				.Fn Q_SIGNSHFT
				gets the bit position of
				.Fa q Ap s
				sign bit relative to bit zero.
				.Pp
				.Fn Q_SSIGN
				sets the sign bit of
				.Fa q
				based on the boolean
				.Fa isneg .
				.Pp
				.Fn Q_CRAWMASK
				and
				.Fn Q_SRAWMASK
				return
				.Fa q Ns -specific
				bit masks for
				.Fa q Ap s
				control bits and sign bit respectively.
				.Pp
				.Fn Q_GCRAW
				and
				.Fn Q_GCVAL
				get the raw masked control bits and value of
				.Fa q Ap s
				control bits respectively.
				.Pp
				.Fn Q_SCVAL
				sets
				.Fa q Ap s
				control bits to the value
				.Fa cv .
				.Pp
				All of those functions operate on
				the following data types:
				.Vt s8q_t ,
				.Vt u8q_t ,
				.Vt s16q_t ,
				.Vt u16q_t ,
				.Vt s32q_t ,
				.Vt u32q_t ,
				.Vt s64q_t ,
				and
				.Vt u64q_t ,
				which are referred to generically as
				.Fa QTYPE .
				The
				.Fa ITYPE
				refers to the
				.Xr stdint 7
				integer types.
				.Pp
				For more details, see
				.Xr qmath 3 .
				.Sh RETURN VALUES
				.Fn Q_SIGNSHFT
				returns the sign bit's position as an integer.
				.Pp
				.Fn Q_SSIGN
				returns the value of
				.Fa q
				post change.
				.Pp
				.Fn Q_CRAWMASK ,
				.Fn Q_SRAWMASK ,
				.Fn Q_GCRAW
				and
				.Fn Q_GCVAL
				return their respective values as integers of the same underlying ITYPE as
				.Fa q .
				.Pp
				.Fn Q_SCVAL
				returns the value of
				.Fa q
				post change.
				.Sh SEE ALSO
				.Xr errno 2 ,
				.Xr qmath 3 ,
				.Xr stdint 7
				.Sh HISTORY
				The
				.Xr qmath 3
				functions first appeared in
				.Fx 13.0 .
				.Sh AUTHORS
				.An -nosplit
				The
				.Xr qmath 3
				functions and this manual page were written by
				.An Lawrence Stewart Aq Mt lstewart@FreeBSD.org
				and sponsored by Netflix, Inc.