1 /* Copyright (C) 2001-2022 Free Software Foundation, Inc. 2 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 License as 7 published by the Free Software Foundation; either version 2.1 of the 8 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 <fpu_control.h> 21 22 int feenableexcept(int excepts)23feenableexcept (int excepts) 24 { 25 fpu_control_t fpcr; 26 fpu_control_t fpcr_new; 27 fpu_control_t updated_fpcr; 28 29 _FPU_GETCW (fpcr); 30 excepts &= FE_ALL_EXCEPT; 31 fpcr_new = fpcr | (excepts << FE_EXCEPT_SHIFT); 32 33 if (fpcr != fpcr_new) 34 { 35 _FPU_SETCW (fpcr_new); 36 37 /* Trapping exceptions are optional in AArch64; the relevant enable 38 bits in FPCR are RES0 hence the absence of support can be detected 39 by reading back the FPCR and comparing with the required value. */ 40 _FPU_GETCW (updated_fpcr); 41 42 if (fpcr_new & ~updated_fpcr) 43 return -1; 44 } 45 46 return (fpcr >> FE_EXCEPT_SHIFT) & FE_ALL_EXCEPT; 47 } 48