| 1 | /* Round long double to integer away from zero. |
|---|
| 2 | Copyright (C) 1997-2022 Free Software Foundation, Inc. |
|---|
| 3 | This file is part of the GNU C Library. |
|---|
| 4 | |
|---|
| 5 | The GNU C Library is free software; you can redistribute it and/or |
|---|
| 6 | modify it under the terms of the GNU Lesser General Public |
|---|
| 7 | License as published by the Free Software Foundation; either |
|---|
| 8 | version 2.1 of the License, or (at your option) any later version. |
|---|
| 9 | |
|---|
| 10 | The GNU C Library is distributed in the hope that it will be useful, |
|---|
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
|---|
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
|---|
| 13 | Lesser General Public License for more details. |
|---|
| 14 | |
|---|
| 15 | You should have received a copy of the GNU Lesser General Public |
|---|
| 16 | License along with the GNU C Library; if not, see |
|---|
| 17 | <https://www.gnu.org/licenses/>. */ |
|---|
| 18 | |
|---|
| 19 | #define NO_MATH_REDIRECT |
|---|
| 20 | #include <math.h> |
|---|
| 21 | |
|---|
| 22 | #include <math_private.h> |
|---|
| 23 | #include <libm-alias-ldouble.h> |
|---|
| 24 | |
|---|
| 25 | |
|---|
| 26 | long double |
|---|
| 27 | __roundl (long double x) |
|---|
| 28 | { |
|---|
| 29 | int32_t j0; |
|---|
| 30 | uint32_t se, i1, i0; |
|---|
| 31 | |
|---|
| 32 | GET_LDOUBLE_WORDS (se, i0, i1, x); |
|---|
| 33 | j0 = (se & 0x7fff) - 0x3fff; |
|---|
| 34 | if (j0 < 31) |
|---|
| 35 | { |
|---|
| 36 | if (j0 < 0) |
|---|
| 37 | { |
|---|
| 38 | se &= 0x8000; |
|---|
| 39 | i0 = i1 = 0; |
|---|
| 40 | if (j0 == -1) |
|---|
| 41 | { |
|---|
| 42 | se |= 0x3fff; |
|---|
| 43 | i0 = 0x80000000; |
|---|
| 44 | } |
|---|
| 45 | } |
|---|
| 46 | else |
|---|
| 47 | { |
|---|
| 48 | uint32_t i = 0x7fffffff >> j0; |
|---|
| 49 | if (((i0 & i) | i1) == 0) |
|---|
| 50 | /* X is integral. */ |
|---|
| 51 | return x; |
|---|
| 52 | |
|---|
| 53 | uint32_t j = i0 + (0x40000000 >> j0); |
|---|
| 54 | if (j < i0) |
|---|
| 55 | se += 1; |
|---|
| 56 | i0 = (j & ~i) | 0x80000000; |
|---|
| 57 | i1 = 0; |
|---|
| 58 | } |
|---|
| 59 | } |
|---|
| 60 | else if (j0 > 62) |
|---|
| 61 | { |
|---|
| 62 | if (j0 == 0x4000) |
|---|
| 63 | /* Inf or NaN. */ |
|---|
| 64 | return x + x; |
|---|
| 65 | else |
|---|
| 66 | return x; |
|---|
| 67 | } |
|---|
| 68 | else |
|---|
| 69 | { |
|---|
| 70 | uint32_t i = 0xffffffff >> (j0 - 31); |
|---|
| 71 | if ((i1 & i) == 0) |
|---|
| 72 | /* X is integral. */ |
|---|
| 73 | return x; |
|---|
| 74 | |
|---|
| 75 | uint32_t j = i1 + (1 << (62 - j0)); |
|---|
| 76 | if (j < i1) |
|---|
| 77 | { |
|---|
| 78 | uint32_t k = i0 + 1; |
|---|
| 79 | if (k < i0) |
|---|
| 80 | { |
|---|
| 81 | se += 1; |
|---|
| 82 | k |= 0x80000000; |
|---|
| 83 | } |
|---|
| 84 | i0 = k; |
|---|
| 85 | } |
|---|
| 86 | i1 = j; |
|---|
| 87 | i1 &= ~i; |
|---|
| 88 | } |
|---|
| 89 | |
|---|
| 90 | SET_LDOUBLE_WORDS (x, se, i0, i1); |
|---|
| 91 | return x; |
|---|
| 92 | } |
|---|
| 93 | libm_alias_ldouble (__round, round) |
|---|
| 94 | |
|---|
