| yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame^] | 1 | /* Disable floating-point exceptions. |
| 2 | Copyright (C) 2004 Free Software Foundation, Inc. |
| 3 | This file is part of the GNU C Library. |
| 4 | Contributed by Aldy Hernandez <aldyh@redhat.com>, 2004. |
| 5 | |
| 6 | The GNU C Library is free software; you can redistribute it and/or |
| 7 | modify it under the terms of the GNU Lesser General Public |
| 8 | License as published by the Free Software Foundation; either |
| 9 | version 2.1 of the License, or (at your option) any later version. |
| 10 | |
| 11 | The GNU C Library is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | Lesser General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU Lesser General Public |
| 17 | License along with the GNU C Library; if not, write to the Free |
| 18 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 19 | 02111-1307 USA. */ |
| 20 | |
| 21 | #include "fenv_libc.h" |
| 22 | #include <syscall.h> |
| 23 | #include <sys/prctl.h> |
| 24 | |
| 25 | int |
| 26 | fedisableexcept (int excepts) |
| 27 | { |
| 28 | unsigned int result = 0, pflags, r; |
| 29 | INTERNAL_SYSCALL_DECL (err); |
| 30 | |
| 31 | INTERNAL_SYSCALL (prctl, err, 2, PR_GET_FPEXC, &pflags); |
| 32 | |
| 33 | /* Save old enable bits. */ |
| 34 | if (pflags & PR_FP_EXC_OVF) |
| 35 | result |= FE_OVERFLOW; |
| 36 | if (pflags & PR_FP_EXC_UND) |
| 37 | result |= FE_UNDERFLOW; |
| 38 | if (pflags & PR_FP_EXC_INV) |
| 39 | result |= FE_INVALID; |
| 40 | if (pflags & PR_FP_EXC_DIV) |
| 41 | result |= FE_DIVBYZERO; |
| 42 | if (pflags & PR_FP_EXC_RES) |
| 43 | result |= FE_INEXACT; |
| 44 | |
| 45 | if (excepts & FE_INEXACT) |
| 46 | pflags &= ~PR_FP_EXC_RES; |
| 47 | if (excepts & FE_DIVBYZERO) |
| 48 | pflags &= ~PR_FP_EXC_DIV; |
| 49 | if (excepts & FE_UNDERFLOW) |
| 50 | pflags &= ~PR_FP_EXC_UND; |
| 51 | if (excepts & FE_OVERFLOW) |
| 52 | pflags &= ~PR_FP_EXC_OVF; |
| 53 | if (excepts & FE_INVALID) |
| 54 | pflags &= ~PR_FP_EXC_INV; |
| 55 | r = INTERNAL_SYSCALL (prctl, err, 2, PR_SET_FPEXC, pflags); |
| 56 | if (INTERNAL_SYSCALL_ERROR_P (r, err)) |
| 57 | return -1; |
| 58 | |
| 59 | return result; |
| 60 | } |