projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 63551311 | 1 | /* Round float to integer away from zero. |
| d7826aa1 | 2 | Copyright (C) 1997, 2011 Free Software Foundation, Inc. |
| 63551311 UD |
3 | This file is part of the GNU C Library. |
| 4 | Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. | |
| 5 | ||
| 6 | The GNU C Library is free software; you can redistribute it and/or | |
| 41bdb6e2 AJ |
7 | modify it under the terms of the GNU Lesser General Public |
| 8 | License as published by the Free Software Foundation; either | |
| 9 | version 2.1 of the License, or (at your option) any later version. | |
| 63551311 UD |
10 | |
| 11 | The GNU C Library is distributed in the hope that it will be useful, | |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 41bdb6e2 | 14 | Lesser General Public License for more details. |
| 63551311 | 15 | |
| 41bdb6e2 AJ |
16 | You should have received a copy of the GNU Lesser General Public |
| 17 | License along with the GNU C Library; if not, write to the Free | |
| 18 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA | |
| 19 | 02111-1307 USA. */ | |
| 63551311 UD |
20 | |
| 21 | #include <math.h> | |
| 22 | ||
| 23 | #include "math_private.h" | |
| 24 | ||
| 25 | ||
| 26 | static const float huge = 1.0e30; | |
| 27 | ||
| 28 | ||
| 29 | float | |
| 30 | __roundf (float x) | |
| 31 | { | |
| 32 | int32_t i0, j0; | |
| 33 | ||
| 34 | GET_FLOAT_WORD (i0, x); | |
| 35 | j0 = ((i0 >> 23) & 0xff) - 0x7f; | |
| 36 | if (j0 < 23) | |
| 37 | { | |
| 38 | if (j0 < 0) | |
| 39 | { | |
| d7826aa1 UD |
40 | math_force_eval (huge + x > 0.0F); |
| 41 | ||
| 42 | i0 &= 0x80000000; | |
| 43 | if (j0 == -1) | |
| 44 | i0 |= 0x3f800000; | |
| 63551311 UD |
45 | } |
| 46 | else | |
| 47 | { | |
| 48 | u_int32_t i = 0x007fffff >> j0; | |
| 49 | if ((i0 & i) == 0) | |
| 50 | /* X is integral. */ | |
| 51 | return x; | |
| d7826aa1 UD |
52 | math_force_eval (huge + x > 0.0F); |
| 53 | ||
| 54 | /* Raise inexact if x != 0. */ | |
| 55 | i0 += 0x00400000 >> j0; | |
| 56 | i0 &= ~i; | |
| 63551311 UD |
57 | } |
| 58 | } | |
| 59 | else | |
| 60 | { | |
| 61 | if (j0 == 0x80) | |
| 62 | /* Inf or NaN. */ | |
| 63 | return x + x; | |
| 64 | else | |
| 65 | return x; | |
| 66 | } | |
| 67 | ||
| 68 | SET_FLOAT_WORD (x, i0); | |
| 69 | return x; | |
| 70 | } | |
| 71 | weak_alias (__roundf, roundf) |