| /* Truncate argument to nearest integral value not larger than the argument. |
| Copyright (C) 1997, 1998 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. |
| |
| 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 <math.h> |
| |
| #include "math_private.h" |
| |
| |
| double |
| __trunc (double x) |
| { |
| int32_t i0, j0; |
| u_int32_t i1; |
| int sx; |
| |
| EXTRACT_WORDS (i0, i1, x); |
| sx = i0 & 0x80000000; |
| j0 = ((i0 >> 20) & 0x7ff) - 0x3ff; |
| if (j0 < 20) |
| { |
| if (j0 < 0) |
| /* The magnitude of the number is < 1 so the result is +-0. */ |
| INSERT_WORDS (x, sx, 0); |
| else |
| INSERT_WORDS (x, sx | (i0 & ~(0x000fffff >> j0)), 0); |
| } |
| else if (j0 > 51) |
| { |
| if (j0 == 0x400) |
| /* x is inf or NaN. */ |
| return x + x; |
| } |
| else |
| { |
| INSERT_WORDS (x, i0, i1 & ~(0xffffffffu >> (j0 - 20))); |
| } |
| |
| return x; |
| } |
| weak_alias (__trunc, trunc) |
| #ifdef NO_LONG_DOUBLE |
| strong_alias (__trunc, __truncl) |
| weak_alias (__trunc, truncl) |
| #endif |
