sysdeps/m68k/fpu/s_llrintf.c

   1 /* Round argument to nearest integral value according to current rounding
   2    direction.
   3    Copyright (C) 1997, 1999 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5    Contributed by Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Lesser General Public
   9    License as published by the Free Software Foundation; either
  10    version 2.1 of the License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Lesser General Public License for more details.
  16
  17    You should have received a copy of the GNU Lesser General Public
  18    License along with the GNU C Library; if not, write to the Free
  19    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  20    02111-1307 USA.  */
  21
  22 #include <math.h>
  23 #include "math_private.h"
  24 #include "mathimpl.h"
  25
  26 long long int
  27 __llrintf (float x)
  28 {
  29   int32_t e;
  30   u_int32_t i, s;
  31   long long int result;
  32
  33   x = __m81_u(__rintf) (x);
  34
  35   GET_FLOAT_WORD (i, x);
  36
  37   e = ((i >> 23) & 0xff) - 0x7f;
  38   if (e < 0)
  39     return 0;
  40   s = i;
  41   i &= 0x7fffff;
  42   i |= 0x800000;
  43
  44   if (e < 63)
  45     {
  46       if (e > 55)
  47         result = (long long int) (i << (e - 55)) << 32;
  48       else if (e > 31)
  49         result = (((long long int) (i >> (55 - e)) << 32) | (i << (e - 23)));
  50       else if (e > 23)
  51         result = i << (e - 23);
  52       else
  53         result = i >> (23 - e);
  54       if (s & 0x80000000)
  55         result = -result;
  56     }
  57   else
  58     /* The number is too large or not finite.  The standard leaves it
  59        undefined what to return when the number is too large to fit in a
  60        `long long int'.  */
  61     result = -1LL;
  62
  63   return result;
  64 }
  65
  66 weak_alias (__llrintf, llrintf)