| 1 | /* Copyright (C) 1996-2024 Free Software Foundation, Inc. |
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| 2 | This file is part of the GNU C Library. |
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| 3 | |
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| 4 | The GNU C Library is free software; you can redistribute it and/or |
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| 5 | modify it under the terms of the GNU Lesser General Public |
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| 6 | License as published by the Free Software Foundation; either |
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| 7 | version 2.1 of the License, or (at your option) any later version. |
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| 8 | |
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| 9 | The GNU C Library is distributed in the hope that it will be useful, |
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| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 12 | Lesser General Public License for more details. |
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| 13 | |
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| 14 | You should have received a copy of the GNU Lesser General Public |
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| 15 | License along with the GNU C Library. If not, see |
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| 16 | <https://www.gnu.org/licenses/>. */ |
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| 17 | |
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| 18 | #include <math.h> |
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| 19 | #include "mathimpl.h" |
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| 20 | |
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| 21 | #ifndef SUFF |
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| 22 | #define SUFF |
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| 23 | #endif |
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| 24 | #ifndef float_type |
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| 25 | #define float_type double |
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| 26 | #endif |
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| 27 | |
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| 28 | #define CONCATX(a,b) __CONCAT(a,b) |
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| 29 | #define s(name) CONCATX(name,SUFF) |
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| 30 | #define m81(func) __m81_u(s(func)) |
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| 31 | |
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| 32 | int |
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| 33 | s(__ieee754_ilogb) (float_type x) |
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| 34 | { |
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| 35 | float_type result; |
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| 36 | unsigned long x_cond; |
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| 37 | |
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| 38 | x_cond = __m81_test (val: x); |
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| 39 | /* We must return consistent values for zero and NaN. */ |
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| 40 | if (x_cond & __M81_COND_ZERO) |
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| 41 | return FP_ILOGB0; |
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| 42 | if (x_cond & (__M81_COND_NAN | __M81_COND_INF)) |
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| 43 | return FP_ILOGBNAN; |
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| 44 | |
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| 45 | __asm ("fgetexp%.x %1, %0" : "=f" (result) : "f" (x)); |
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| 46 | return (int) result; |
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| 47 | } |
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| 48 | |
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