1 /* Round argument to nearest integral value according to current rounding
2 direction.
3 Copyright (C) 1997, 1999, 2006 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
6 Jakub Jelinek <jj@ultra.linux.cz>, 1999.
7
8 The GNU C Library is free software; you can redistribute it and/or
9 modify it under the terms of the GNU Lesser General Public
10 License as published by the Free Software Foundation; either
11 version 2.1 of the License, or (at your option) any later version.
12
13 The GNU C Library is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
17
18 You should have received a copy of the GNU Lesser General Public
19 License along with the GNU C Library; if not, write to the Free
20 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
21 02111-1307 USA. */
22
23 #include "quadmath-imp.h"
24
25 static const __float128 two112[2] =
26 {
27 5.19229685853482762853049632922009600E+33Q, /* 0x406F000000000000, 0 */
28 -5.19229685853482762853049632922009600E+33Q /* 0xC06F000000000000, 0 */
29 };
30
31 long long int
llrintq(__float128 x)32 llrintq (__float128 x)
33 {
34 int32_t j0;
35 uint64_t i0,i1;
36 volatile __float128 w;
37 __float128 t;
38 long long int result;
39 int sx;
40
41 GET_FLT128_WORDS64 (i0, i1, x);
42 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
43 sx = i0 >> 63;
44 i0 &= 0x0000ffffffffffffLL;
45 i0 |= 0x0001000000000000LL;
46
47 if (j0 < (int32_t) (8 * sizeof (long long int)) - 1)
48 {
49 w = two112[sx] + x;
50 t = w - two112[sx];
51 GET_FLT128_WORDS64 (i0, i1, t);
52 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
53 i0 &= 0x0000ffffffffffffLL;
54 i0 |= 0x0001000000000000LL;
55
56 if (j0 < 0)
57 result = 0;
58 else if (j0 <= 48)
59 result = i0 >> (48 - j0);
60 else
61 result = ((long long int) i0 << (j0 - 48)) | (i1 >> (112 - j0));
62 }
63 else
64 {
65 /* The number is too large. It is left implementation defined
66 what happens. */
67 return (long long int) x;
68 }
69
70 return sx ? -result : result;
71 }
72