| /* Round double to integer away from zero. |
| Copyright (C) 2011-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 2011. |
| |
| 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, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| /* Based on a version which carries the following copyright: */ |
| |
| /* |
| * ==================================================== |
| * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| * |
| * Developed at SunPro, a Sun Microsystems, Inc. business. |
| * Permission to use, copy, modify, and distribute this |
| * software is freely granted, provided that this notice |
| * is preserved. |
| * ==================================================== |
| */ |
| |
| #include <math.h> |
| #include <math_private.h> |
| #include <stdint.h> |
| |
| /* |
| * floor(x) |
| * Return x rounded toward -inf to integral value |
| * Method: |
| * Bit twiddling. |
| * Exception: |
| * Inexact flag raised if x not equal to floor(x). |
| */ |
| |
| static const double huge = 1.0e300; |
| |
| |
| double |
| __floor (double x) |
| { |
| int64_t i0; |
| EXTRACT_WORDS64(i0,x); |
| int32_t j0 = ((i0>>52)&0x7ff)-0x3ff; |
| if(__builtin_expect(j0<52, 1)) { |
| if(j0<0) { /* raise inexact if x != 0 */ |
| math_force_eval(huge+x);/* return 0*sign(x) if |x|<1 */ |
| if(i0>=0) {i0=0;} |
| else if((i0&0x7fffffffffffffffl)!=0) |
| { i0=0xbff0000000000000l;} |
| } else { |
| uint64_t i = (0x000fffffffffffffl)>>j0; |
| if((i0&i)==0) return x; /* x is integral */ |
| math_force_eval(huge+x); /* raise inexact flag */ |
| if(i0<0) i0 += (0x0010000000000000l)>>j0; |
| i0 &= (~i); |
| } |
| INSERT_WORDS64(x,i0); |
| } else if (j0==0x400) |
| return x+x; /* inf or NaN */ |
| return x; |
| } |
| #ifndef __floor |
| weak_alias (__floor, floor) |
| # ifdef NO_LONG_DOUBLE |
| strong_alias (__floor, __floorl) |
| weak_alias (__floor, floorl) |
| # endif |
| #endif |
