sysdeps/powerpc/s_lround.c

   1 /* Round double value to long int.
   2    Copyright (C) 1997 Free Software Foundation, Inc.
   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 Library General Public License as
   7    published by the Free Software Foundation; either version 2 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    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #include <math.h>
  21
  22 /* I think that what this routine is supposed to do is round a value
  23    to the nearest integer, with values exactly on the boundary rounded
  24    away from zero.  */
  25 /* This routine relies on (long int)x, when x is out of range of a long int,
  26    clipping to MAX_LONG or MIN_LONG.  */
  27
  28 long int
  29 __lround (double x)
  30 {
  31   double xrf;
  32   long int xr;
  33   xr = (long int) x;
  34   xrf = (double) xr;
  35   if (x >= 0.0)
  36     if (x - xrf >= 0.5 && x - xrf < 1.0 && x+1 > 0)
  37       return x+1;
  38     else
  39       return x;
  40   else
  41     if (xrf - x >= 0.5 && xrf - x < 1.0 && x-1 < 0)
  42       return x-1;
  43     else
  44       return x;
  45 }
  46 weak_alias (__lround, lround)
  47 #ifdef NO_LONG_DOUBLE
  48 strong_alias (__lround, __lroundl)
  49 weak_alias (__lround, lroundl)
  50 #endif