projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| dfd2257a UD |
1 | /* Round argument to nearest integral value according to current rounding |
| 2 | direction. | |
| a334319f | 3 | Copyright (C) 1997, 2004 Free Software Foundation, Inc. |
| dfd2257a UD |
4 | This file is part of the GNU C Library. |
| 5 | Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. | |
| 6 | ||
| 7 | The GNU C Library is free software; you can redistribute it and/or | |
| 41bdb6e2 AJ |
8 | modify it under the terms of the GNU Lesser General Public |
| 9 | License as published by the Free Software Foundation; either | |
| 10 | version 2.1 of the License, or (at your option) any later version. | |
| dfd2257a UD |
11 | |
| 12 | The GNU C Library is distributed in the hope that it will be useful, | |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 41bdb6e2 | 15 | Lesser General Public License for more details. |
| dfd2257a | 16 | |
| 41bdb6e2 AJ |
17 | You should have received a copy of the GNU Lesser General Public |
| 18 | License along with the GNU C Library; if not, write to the Free | |
| 19 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA | |
| 20 | 02111-1307 USA. */ | |
| dfd2257a UD |
21 | |
| 22 | #include <math.h> | |
| 23 | ||
| 24 | #include "math_private.h" | |
| 25 | ||
| 26 | static const long double two63[2] = | |
| 27 | { | |
| 28 | 9.223372036854775808000000e+18, /* 0x403E, 0x00000000, 0x00000000 */ | |
| 29 | -9.223372036854775808000000e+18 /* 0xC03E, 0x00000000, 0x00000000 */ | |
| 30 | }; | |
| 31 | ||
| 32 | ||
| 33 | long int | |
| 34 | __lrintl (long double x) | |
| 35 | { | |
| 36 | int32_t se,j0; | |
| af6f3906 | 37 | u_int32_t i0, i1; |
| dfd2257a UD |
38 | long int result; |
| 39 | volatile long double w; | |
| 40 | long double t; | |
| 41 | int sx; | |
| 42 | ||
| 43 | GET_LDOUBLE_WORDS (se, i0, i1, x); | |
| 44 | ||
| 45 | sx = (se >> 15) & 1; | |
| 46 | j0 = (se & 0x7fff) - 0x3fff; | |
| 47 | ||
| 48 | if (j0 < 31) | |
| 49 | { | |
| a334319f UD |
50 | if (j0 < -1) |
| 51 | return 0; | |
| 52 | else | |
| 53 | { | |
| 54 | w = two63[sx] + x; | |
| 55 | t = w - two63[sx]; | |
| 56 | GET_LDOUBLE_WORDS (se, i0, i1, t); | |
| 57 | j0 = (se & 0x7fff) - 0x3fff; | |
| dfd2257a | 58 | |
| a334319f UD |
59 | result = i0 >> (31 - j0); |
| 60 | } | |
| dfd2257a | 61 | } |
| cc3fa755 | 62 | else if (j0 < (int32_t) (8 * sizeof (long int)) - 1) |
| dfd2257a UD |
63 | { |
| 64 | if (j0 >= 63) | |
| 65 | result = ((long int) i0 << (j0 - 31)) | (i1 << (j0 - 63)); | |
| 66 | else | |
| 67 | { | |
| 68 | w = two63[sx] + x; | |
| 69 | t = w - two63[sx]; | |
| 70 | GET_LDOUBLE_WORDS (se, i0, i1, t); | |
| 71 | j0 = (se & 0x7fff) - 0x3fff; | |
| 72 | ||
| 3eb61415 UD |
73 | if (j0 == 31) |
| 74 | result = (long int) i0; | |
| 75 | else | |
| 76 | result = ((long int) i0 << (j0 - 31)) | (i1 >> (63 - j0)); | |
| dfd2257a UD |
77 | } |
| 78 | } | |
| 79 | else | |
| 80 | { | |
| 81 | /* The number is too large. It is left implementation defined | |
| 82 | what happens. */ | |
| 83 | return (long int) x; | |
| 84 | } | |
| 85 | ||
| 86 | return sx ? -result : result; | |
| 87 | } | |
| 88 | ||
| 89 | weak_alias (__lrintl, lrintl) |