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
|
/* Round argument to nearest integral value according to current rounding
direction.
Copyright (C) 1997, 2004, 2006 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <math.h>
#include "math_private.h"
static const double two52[2] =
{
4.50359962737049600000e+15, /* 0x43300000, 0x00000000 */
-4.50359962737049600000e+15, /* 0xC3300000, 0x00000000 */
};
long long int
__llrint (double x)
{
int32_t j0;
u_int32_t i1, i0;
long long int result;
volatile double w;
double t;
int sx;
EXTRACT_WORDS (i0, i1, x);
j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
sx = i0 >> 31;
i0 &= 0xfffff;
i0 |= 0x100000;
if (j0 < 20)
{
w = two52[sx] + x;
t = w - two52[sx];
EXTRACT_WORDS (i0, i1, t);
j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
i0 &= 0xfffff;
i0 |= 0x100000;
result = (j0 < 0 ? 0 : i0 >> (20 - j0));
}
else if (j0 < (int32_t) (8 * sizeof (long long int)) - 1)
{
if (j0 >= 52)
result = (((long long int) i0 << 32) | i1) << (j0 - 52);
else
{
w = two52[sx] + x;
t = w - two52[sx];
EXTRACT_WORDS (i0, i1, t);
j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
i0 &= 0xfffff;
i0 |= 0x100000;
if (j0 == 20)
result = (long long int) i0;
else
result = ((long long int) i0 << (j0 - 20)) | (i1 >> (52 - j0));
}
}
else
{
/* The number is too large. It is left implementation defined
what happens. */
return (long long int) x;
}
return sx ? -result : result;
}
weak_alias (__llrint, llrint)
#ifdef NO_LONG_DOUBLE
strong_alias (__llrint, __llrintl)
weak_alias (__llrint, llrintl)
#endif
|
