| 1 | /* Round double value to long long int. |
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| 2 | Copyright (C) 1997-2022 Free Software Foundation, Inc. |
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| 3 | This file is part of the GNU C Library. |
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| 4 | |
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| 5 | The GNU C Library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Lesser General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2.1 of the License, or (at your option) any later version. |
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| 9 | |
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| 10 | The GNU C Library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Lesser General Public License for more details. |
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| 14 | |
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| 15 | You should have received a copy of the GNU Lesser General Public |
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| 16 | License along with the GNU C Library; if not, see |
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| 17 | <https://www.gnu.org/licenses/>. */ |
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| 18 | |
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| 19 | #define lround __hidden_lround |
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| 20 | #define __lround __hidden___lround |
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| 21 | |
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| 22 | #include <fenv.h> |
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| 23 | #include <limits.h> |
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| 24 | #include <math.h> |
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| 25 | #include <sysdep.h> |
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| 26 | |
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| 27 | #include <math_private.h> |
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| 28 | #include <libm-alias-double.h> |
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| 29 | #include <fix-fp-int-convert-overflow.h> |
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| 30 | |
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| 31 | long long int |
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| 32 | __llround (double x) |
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| 33 | { |
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| 34 | int32_t j0; |
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| 35 | int64_t i0; |
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| 36 | long long int result; |
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| 37 | int sign; |
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| 38 | |
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| 39 | EXTRACT_WORDS64 (i0, x); |
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| 40 | j0 = ((i0 >> 52) & 0x7ff) - 0x3ff; |
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| 41 | sign = i0 < 0 ? -1 : 1; |
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| 42 | i0 &= UINT64_C(0xfffffffffffff); |
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| 43 | i0 |= UINT64_C(0x10000000000000); |
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| 44 | |
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| 45 | if (j0 < (int32_t) (8 * sizeof (long long int)) - 1) |
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| 46 | { |
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| 47 | if (j0 < 0) |
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| 48 | return j0 < -1 ? 0 : sign; |
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| 49 | else if (j0 >= 52) |
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| 50 | result = i0 << (j0 - 52); |
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| 51 | else |
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| 52 | { |
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| 53 | i0 += UINT64_C(0x8000000000000) >> j0; |
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| 54 | |
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| 55 | result = i0 >> (52 - j0); |
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| 56 | } |
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| 57 | } |
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| 58 | else |
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| 59 | { |
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| 60 | #ifdef FE_INVALID |
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| 61 | /* The number is too large. Unless it rounds to LLONG_MIN, |
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| 62 | FE_INVALID must be raised and the return value is |
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| 63 | unspecified. */ |
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| 64 | if (FIX_DBL_LLONG_CONVERT_OVERFLOW && x != (double) LLONG_MIN) |
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| 65 | { |
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| 66 | feraiseexcept (FE_INVALID); |
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| 67 | return sign == 1 ? LLONG_MAX : LLONG_MIN; |
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| 68 | } |
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| 69 | #endif |
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| 70 | return (long long int) x; |
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| 71 | } |
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| 72 | |
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| 73 | return sign * result; |
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| 74 | } |
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| 75 | |
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| 76 | libm_alias_double (__llround, llround) |
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| 77 | |
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| 78 | /* long has the same width as long long on LP64 machines, so use an alias. */ |
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| 79 | #undef lround |
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| 80 | #undef __lround |
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| 81 | #ifdef _LP64 |
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| 82 | strong_alias (__llround, __lround) |
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| 83 | libm_alias_double (__lround, lround) |
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| 84 | #endif |
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| 85 | |
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