sysdeps/m68k/fpu/s_llrint.c

   1 /* Round argument to nearest integral value according to current rounding
   2    direction.
   3    Copyright (C) 1997 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 Library General Public License as
   9    published by the Free Software Foundation; either version 2 of the
  10    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    Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Library General Public
  18    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  19    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #define __LIBC_M81_MATH_INLINES
  23 #include <math.h>
  24 #include "math_private.h"
  25
  26 long long int
  27 __llrint (long double x)
  28 {
  29   int32_t se, sx;
  30   u_int32_t h, l;
  31   long long int result;
  32
  33   x = __m81_u(__rintl) (x);
  34
  35   /* We could use __fixxfdi from libgcc, but here we can take advantage of
  36      the known floating point format.  */
  37   GET_LDOUBLE_WORDS (se, h, l, x);
  38
  39   sx = se & (1 << 15);
  40   se = (se ^ sx) - 0x3fff;
  41
  42   if (se < 64)
  43     {
  44       if (se > 31)
  45         result = (((long long int) (h >> (63 - se)) << 32)
  46                   | (l >> (63 - se)) | (h << (se - 31)));
  47       else
  48         result = h >> (31 - se);
  49       if (sx)
  50         result = -result;
  51     }
  52   else
  53     /* Too large.  The number is either +-inf or NaN or it is too
  54        large to be effected by rounding.  The standard leaves it
  55        undefined what to return when the number is too large to fit in
  56        a `long long int'.  */
  57     result = -1LL;
  58
  59   return result;
  60 }
  61
  62 weak_alias (__llrint, llrint)