1 /* Enable floating-point exceptions. 2 Copyright (C) 1999-2022 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 #include <fenv.h> 20 #include <unistd.h> 21 #include <ldsodefs.h> 22 #include <dl-procinfo.h> 23 24 int feenableexcept(int excepts)25feenableexcept (int excepts) 26 { 27 unsigned short int new_exc; 28 unsigned short int old_exc; 29 30 /* Get the current control word. */ 31 __asm__ ("fstcw %0" : "=m" (*&new_exc)); 32 33 excepts &= FE_ALL_EXCEPT; 34 old_exc = (~new_exc) & FE_ALL_EXCEPT; 35 36 new_exc &= ~excepts; 37 __asm__ ("fldcw %0" : : "m" (*&new_exc)); 38 39 /* If the CPU supports SSE we set the MXCSR as well. */ 40 if (CPU_FEATURE_USABLE (SSE)) 41 { 42 unsigned int xnew_exc; 43 44 /* Get the current control word. */ 45 __asm__ ("stmxcsr %0" : "=m" (*&xnew_exc)); 46 47 xnew_exc &= ~(excepts << 7); 48 49 __asm__ ("ldmxcsr %0" : : "m" (*&xnew_exc)); 50 } 51 52 return old_exc; 53 } 54