ref: 1b92befa76f09641c30fa751ce33af5ab47c4499
dir: /libstd/floatbits.myr/
pkg std =
const float64bits : (flt : float64 -> uint64)
const float32bits : (flt : float32 -> uint32)
const float64frombits : (bits : uint64 -> float64)
const float32frombits : (bits : uint32 -> float32)
const float64explode : (flt : float64 -> (bool, uint64, int32))
const float32explode : (flt : float64 -> (bool, uint64, int32))
;;
const float64bits = {flt; -> (&flt castto(uint64#))#}
const float32bits = {flt; -> (&flt castto(uint32#))#}
const float64frombits = {bits; -> (&bits castto(float64#))#}
const float32frombits = {bits; -> (&bits castto(float32#))#}
const float64explode = {flt
var bits, isneg, mant, exp
bits = float64bits(flt)
isneg = (bits >> 63) == 0 /* msb is sign bit */
exp = (bits >> 52) & 0x7ff /* exp is in bits [52..63] */
mant = bits & ((1ul << 52) - 1) /* msb is in bits [..51] */
/* add back the implicit bit if this is not a denormal */
if exp != 0
mant |= 1ul << 52
else
exp = 1
;;
/*
adjust for exponent bias. nb: because we are
treating the mantissa as m.0 instead of 0.m,
our exponent bias needs to be offset by the
size of m
*/
-> (isneg, mant, (exp castto(int32)) - 1075)
}
const float32explode = {flt
var bits, isneg, mant, exp
bits = float64bits(flt) castto(uint64)
isneg = (bits >> 31) == 0 /* msb is sign bit */
exp = (bits >> 22) & 0xff /* exp is in bits [23..30] */
mant = bits & ((1ul << 52) - 1) /* msb is in bits [0..22] */
/* add back the implicit bit if this is not a denormal */
if exp != 0
mant |= 1ul << 22
else
exp = 1
;;
/*
adjust for exponent bias. nb: because we are
treating the mantissa as m.0 instead of 0.m,
our exponent bias needs to be offset by the
size of m
*/
-> (isneg, mant, (exp castto(int32)) - 149)
}