| 1 | /* Set floating-point environment exception handling. |
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| 2 | Copyright (C) 2001-2022 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 | #include <fenv.h> |
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| 20 | #include <math.h> |
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| 21 | |
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| 22 | int |
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| 23 | fesetexceptflag (const fexcept_t *flagp, int excepts) |
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| 24 | { |
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| 25 | fenv_t temp; |
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| 26 | unsigned int mxcsr; |
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| 27 | |
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| 28 | /* XXX: Do we really need to set both the exception in both units? |
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| 29 | Shouldn't it be enough to set only the SSE unit? */ |
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| 30 | |
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| 31 | /* Get the current x87 FPU environment. We have to do this since we |
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| 32 | cannot separately set the status word. */ |
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| 33 | __asm__ ("fnstenv %0" : "=m" (*&temp)); |
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| 34 | |
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| 35 | temp.__status_word &= ~(excepts & FE_ALL_EXCEPT); |
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| 36 | temp.__status_word |= *flagp & excepts & FE_ALL_EXCEPT; |
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| 37 | |
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| 38 | /* Store the new status word (along with the rest of the environment. |
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| 39 | Possibly new exceptions are set but they won't get executed unless |
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| 40 | the next floating-point instruction. */ |
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| 41 | __asm__ ("fldenv %0" : : "m" (*&temp)); |
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| 42 | |
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| 43 | /* And now the same for SSE. */ |
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| 44 | __asm__ ("stmxcsr %0" : "=m" (*&mxcsr)); |
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| 45 | |
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| 46 | mxcsr &= ~(excepts & FE_ALL_EXCEPT); |
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| 47 | mxcsr |= *flagp & excepts & FE_ALL_EXCEPT; |
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| 48 | |
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| 49 | __asm__ ("ldmxcsr %0" : : "m" (*&mxcsr)); |
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| 50 | |
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| 51 | /* Success. */ |
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| 52 | return 0; |
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| 53 | } |
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| 54 | |
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