| 1 | /* Copyright (C) 2011-2020 Free Software Foundation, Inc. | 
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| 2 | This file is part of the GNU C Library. | 
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| 3 | Contributed by Ulrich Drepper <drepper@gmail.com>, 2011. | 
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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 | #include <math.h> | 
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| 20 | #include <math_private.h> | 
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| 21 | #include <math-svid-compat.h> | 
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| 22 | #include <libm-alias-double.h> | 
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| 23 |  | 
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| 24 |  | 
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| 25 | #if LIBM_SVID_COMPAT && (SHLIB_COMPAT (libm, GLIBC_2_0, GLIBC_2_29) \ | 
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| 26 | || defined NO_LONG_DOUBLE \ | 
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| 27 | || defined LONG_DOUBLE_COMPAT) | 
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| 28 | /* wrapper pow */ | 
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| 29 | double | 
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| 30 | __pow_compat (double x, double y) | 
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| 31 | { | 
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| 32 | double z = __ieee754_pow (x, y); | 
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| 33 | if (__glibc_unlikely (!isfinite (z))) | 
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| 34 | { | 
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| 35 | if (_LIB_VERSION != _IEEE_) | 
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| 36 | { | 
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| 37 | if (isfinite (x) && isfinite (y)) | 
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| 38 | { | 
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| 39 | if (isnan (z)) | 
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| 40 | /* pow neg**non-int */ | 
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| 41 | return __kernel_standard (x, y, 24); | 
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| 42 | else if (x == 0.0 && y < 0.0) | 
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| 43 | { | 
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| 44 | if (signbit (x) && signbit (z)) | 
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| 45 | /* pow(-0.0,negative) */ | 
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| 46 | return __kernel_standard (x, y, 23); | 
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| 47 | else | 
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| 48 | /* pow(+0.0,negative) */ | 
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| 49 | return __kernel_standard (x, y, 43); | 
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| 50 | } | 
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| 51 | else | 
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| 52 | /* pow overflow */ | 
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| 53 | return __kernel_standard (x, y, 21); | 
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| 54 | } | 
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| 55 | } | 
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| 56 | } | 
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| 57 | else if (__builtin_expect (z == 0.0, 0) | 
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| 58 | && isfinite (x) && x != 0 && isfinite (y) | 
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| 59 | && _LIB_VERSION != _IEEE_) | 
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| 60 | /* pow underflow */ | 
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| 61 | return __kernel_standard (x, y, 22); | 
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| 62 |  | 
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| 63 | return z; | 
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| 64 | } | 
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| 65 | # if SHLIB_COMPAT (libm, GLIBC_2_0, GLIBC_2_29) | 
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| 66 | compat_symbol (libm, __pow_compat, pow, GLIBC_2_0); | 
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| 67 | # endif | 
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| 68 | # ifdef NO_LONG_DOUBLE | 
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| 69 | weak_alias (__pow_compat, powl) | 
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| 70 | # endif | 
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| 71 | # ifdef LONG_DOUBLE_COMPAT | 
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| 72 | /* Work around gas bug "multiple versions for symbol".  */ | 
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| 73 | weak_alias (__pow_compat, __pow_compat_alias) | 
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| 74 |  | 
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| 75 | LONG_DOUBLE_COMPAT_CHOOSE_libm_powl ( | 
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| 76 | compat_symbol (libm, __pow_compat_alias, powl, FIRST_VERSION_libm_powl), ); | 
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| 77 | # endif | 
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| 78 | #endif | 
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| 79 |  | 
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