1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
pkg std =
const flt64bits : (flt : flt64 -> int64)
const flt32bits : (flt : flt32 -> int32)
const flt64inf : (-> flt64)
const flt64nan : (-> flt64)
const flt32inf : (-> flt32)
const flt32nan : (-> flt32)
generic isnan : (f : @a::floating -> bool)
const flt64frombits : (bits : uint64 -> flt64)
const flt32frombits : (bits : uint32 -> flt32)
const flt64explode : (flt : flt64 -> (bool, int64, int64))
const flt32explode : (flt : flt32 -> (bool, int32, int32))
const flt64assem : (sign : bool, mant : int64, exp : int64 -> flt64)
const flt32assem : (sign : bool, mant : int32, exp : int32 -> flt32)
;;
const flt64bits = {flt; -> (&flt : int64#)#}
const flt32bits = {flt; -> (&flt : int32#)#}
const flt64frombits = {bits; -> (&bits : flt64#)#}
const flt32frombits = {bits; -> (&bits : flt32#)#}
const flt64explode = {flt
var bits, isneg, mant, exp
bits = flt64bits(flt)
isneg = (bits >> 63) != 0 /* msb is sign bit */
exp = (bits >> 52) & 0x7ff /* exp is in bits [52..63] */
mant = bits & ((1l << 52) - 1) /* msb is in bits [..51] */
/* add back the implicit bit if this is not a denormal */
if exp != 0
mant |= 1l << 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)
}
const flt32explode = {flt
var bits, isneg, mant, exp
bits = flt32bits(flt)
isneg = (bits >> 31) != 0 /* msb is sign bit */
exp = (bits >> 22) & 0xff /* exp is in bits [23..30] */
mant = bits & ((1 << 22) - 1) /* msb is in bits [0..22] */
/* add back the implicit bit if this is not a denormal */
if exp != 0
mant |= 1 << 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)
}
const flt64assem = {sign, mant, exp
var s, m, e
s = (sign : uint64)
e = (exp : uint64) & 0x7ff
m = (mant : uint64) & ((1ul<<52) - 1)
-> std.flt64frombits((s << 63) | (e << 52) | m)
}
const flt32assem = {sign, mant, exp
var s, m, e
s = (sign : uint32)
e = (exp : uint32) & 0xff
m = (mant : uint32) & ((1<<22) - 1)
-> std.flt32frombits(s << 31 | e << 22 | m)
}
generic isnan = {f
var b
b = flt64bits((f : flt64))
-> (b >> 52) & 0x7ffl == 0x7ffl && \
b & ~(0x7ffl) != 0
}
const flt64inf = {
-> std.flt64frombits(0x7ff0000000000000ul)
}
const flt64nan = {
-> std.flt64frombits(0x7ff8000000000000ul)
}
const flt32inf = {
-> std.flt32frombits(0x7f800000)
}
const flt32nan = {
-> std.flt32frombits(0x7fc00000)
}
|
