| /* Software floating-point emulation. |
| Helper routine for _Q_* routines. |
| Simulate exceptions using double arithmetics. |
| Copyright (C) 1999 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Jakub Jelinek (jj@ultra.linux.cz). |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #include "soft-fp.h" |
| |
| unsigned long long ___Q_numbers [] = { |
| 0x0000000000000000ULL, /* Zero */ |
| 0x0010100000000000ULL, /* Very tiny number */ |
| 0x0010000000000000ULL, /* Minimum normalized number */ |
| 0x7fef000000000000ULL, /* A huge double number */ |
| }; |
| |
| double ___Q_simulate_exceptions(int exceptions) |
| { |
| double d, *p = (double *)___Q_numbers; |
| if (exceptions & FP_EX_INVALID) |
| d = p[0]/p[0]; |
| if (exceptions & FP_EX_OVERFLOW) |
| { |
| d = p[3] + p[3]; |
| exceptions &= ~FP_EX_INEXACT; |
| } |
| if (exceptions & FP_EX_UNDERFLOW) |
| { |
| if (exceptions & FP_EX_INEXACT) |
| { |
| d = p[2] * p[2]; |
| exceptions &= ~FP_EX_INEXACT; |
| } |
| else |
| d = p[1] - p[2]; |
| } |
| if (exceptions & FP_EX_DIVZERO) |
| d = 1.0/p[0]; |
| if (exceptions & FP_EX_INEXACT) |
| d = p[3] - p[2]; |
| return d; |
| } |