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
| | #include "libm.h"
#ifdef LONG_DOUBLE_IS_BINARY64
long double fmodl(long double x, long double y)
{
return fmod(x, y);
}
#elif defined(LONG_DOUBLE_IS_X87_EXTENDED) || defined(LONG_DOUBLE_IS_BINARY128)
long double fmodl(long double x, long double y)
{
union ldshape ux = {x}, uy = {y};
int ex = ux.i.se & 0x7fff;
int ey = uy.i.se & 0x7fff;
int sx = ux.i.se & 0x8000;
if (y == 0 || isnan(y) || ex == 0x7fff)
return (x*y)/(x*y);
ux.i.se = ex;
uy.i.se = ey;
if (ux.f <= uy.f) {
if (ux.f == uy.f)
return 0*x;
return x;
}
/* normalize x and y */
if (!ex) {
ux.f *= 0x1p120f;
ex = ux.i.se - 120;
}
if (!ey) {
uy.f *= 0x1p120f;
ey = uy.i.se - 120;
}
/* x mod y */
#ifdef LONG_DOUBLE_IS_X87_EXTENDED
uint64_t i, mx, my;
mx = ux.i.m;
my = uy.i.m;
for (; ex > ey; ex--) {
i = mx - my;
if (mx >= my) {
if (i == 0)
return 0*x;
mx = 2*i;
} else if (2*mx < mx) {
mx = 2*mx - my;
} else {
mx = 2*mx;
}
}
i = mx - my;
if (mx >= my) {
if (i == 0)
return 0*x;
mx = i;
}
for (; mx >> 63 == 0; mx *= 2, ex--);
ux.i.m = mx;
#elif defined(LONG_DOUBLE_IS_BINARY128)
uint64_t hi, lo, xhi, xlo, yhi, ylo;
xhi = (ux.i2.hi & -1ULL>>16) | 1ULL<<48;
yhi = (uy.i2.hi & -1ULL>>16) | 1ULL<<48;
xlo = ux.i2.lo;
ylo = uy.i2.lo;
for (; ex > ey; ex--) {
hi = xhi - yhi;
lo = xlo - ylo;
if (xlo < ylo)
hi -= 1;
if (hi >> 63 == 0) {
if ((hi|lo) == 0)
return 0*x;
xhi = 2*hi + (lo>>63);
xlo = 2*lo;
} else {
xhi = 2*xhi + (xlo>>63);
xlo = 2*xlo;
}
}
hi = xhi - yhi;
lo = xlo - ylo;
if (xlo < ylo)
hi -= 1;
if (hi >> 63 == 0) {
if ((hi|lo) == 0)
return 0*x;
xhi = hi;
xlo = lo;
}
for (; xhi >> 48 == 0; xhi = 2*xhi + (xlo>>63), xlo = 2*xlo, ex--);
ux.i2.hi = xhi;
ux.i2.lo = xlo;
#endif
/* scale result */
if (ex <= 0) {
ux.i.se = (ex+120)|sx;
ux.f *= 0x1p-120f;
} else
ux.i.se = ex|sx;
return ux.f;
}
#endif
|