Lines Matching +full:control +full:- +full:bit

31 .Nd fixed-point math library based on the
39 data types and APIs support fixed-point math based on the
79 None of the operations is affected by the floating-point environment.
86 .Bl -column "isgreaterequal" "bessel function of the second kind of the order 0"
134 .Ss Functions which manipulate the control/sign data bits
136 .Xr Q_SIGNSHFT 3	sign bit position
137 .Xr Q_SSIGN 3	sign bit
138 .Xr Q_CRAWMASK 3	control bitmask
140 .Xr Q_GCRAW 3	raw control bits
141 .Xr Q_GCVAL 3	value of control bits
142 .Xr Q_SCVAL 3	set control bits
173 .Xr Q_NCBITS 3	number of reserved control bits
177 .Xr Q_NFCBITS 3	number of control-encoded fractional bits
181 .Xr Q_RPSHFT 3	bit position of radix point
185 .Xr Q_SHL 3	left-shifted value
186 .Xr Q_SHR 3	right-shifted value
193 data types and APIs support fixed-point math based on the
201 .Pq excluding the sign bit for signed types ,
207 .Bd -literal -offset indent
233 of all q_t data types are reserved for embedded control data:
234 .Bl -dash
236 bits 1-2 specify the binary radix point shift index operand, with 00,01,10,11 ==
252 Additionally, the most significant bit
254 of signed Q types stores the sign bit, with bit value 0 representing a positive
255 number and bit value 1 representing a negative number.
256 Negative numbers are stored as absolute values with the sign bit set, rather
258 This avoids having to bit shift negative numbers, which can result in undefined
262 distinct data bit types and associated bit counts.
263 Data bit types/labels, listed in LSB to MSB order, are: control
273 .Bd -literal -offset indent
284 Important bit counts are: total, control, control-encoded fractional, maximum
290 The count of control-encoded fractional bits is derived from calculating the
291 number of fractional bits per the control bit encoding scheme.
292 For example, the control bits binary value of 101 encodes a fractional bit
296 counts of total bits and control/sign bits.
297 For example, a s32q_t has a maximum of 32 - 3 - 1 = 28 fractional bits.
300 control-encoded fractional bits and the maximum fractional bits.
301 For example, a s32q_t with 32 control-encoded fractional bits is effectively
305 total bits and all other non-integer data bits
306 .Pq the sum of control, fractional and sign bits.
307 For example, a s32q_t with 8 effective fractional bits has 32 - 3 - 8 - 1 = 20 integer
310 been reserved for fractional data, e.g., when the number of control-encoded
315 .Bd -literal -offset indent
327 Q_TOSTR(a, -1, 10, buf, sizeof(buf));
333 initialise it with the fixed-point value for 5/3, and render a debugging
335 .Pq including its full precision decimal C-string representation ,
337 .Bd -literal -offset indent
342 Q_TOSTR(s32, -1, 10, buf, sizeof(buf));
347 .Bd -literal -offset indent
382 .An -nosplit