sysdeps/ieee754/ldbl-128/s_sincosl.c

   1 /* Compute sine and cosine of argument.
   2    Copyright (C) 1997-2014 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
   5                   Jakub Jelinek <jj@ultra.linux.cz>.
   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, see
  19    <http://www.gnu.org/licenses/>.  */
  20
  21 #include <math.h>
  22
  23 #include <math_private.h>
  24
  25 void
  26 __sincosl (long double x, long double *sinx, long double *cosx)
  27 {
  28   int64_t ix;
  29
  30   /* High word of x. */
  31   GET_LDOUBLE_MSW64 (ix, x);
  32
  33   /* |x| ~< pi/4 */
  34   ix &= 0x7fffffffffffffffLL;
  35   if (ix <= 0x3ffe921fb54442d1LL)
  36     __kernel_sincosl (x, 0.0L, sinx, cosx, 0);
  37   else if (ix >= 0x7fff000000000000LL)
  38     {
  39       /* sin(Inf or NaN) is NaN */
  40       *sinx = *cosx = x - x;
  41     }
  42   else
  43     {
  44       /* Argument reduction needed.  */
  45       long double y[2];
  46       int n;
  47
  48       n = __ieee754_rem_pio2l (x, y);
  49       switch (n & 3)
  50         {
  51         case 0:
  52           __kernel_sincosl (y[0], y[1], sinx, cosx, 1);
  53           break;
  54         case 1:
  55           __kernel_sincosl (y[0], y[1], cosx, sinx, 1);
  56           *cosx = -*cosx;
  57           break;
  58         case 2:
  59           __kernel_sincosl (y[0], y[1], sinx, cosx, 1);
  60           *sinx = -*sinx;
  61           *cosx = -*cosx;
  62           break;
  63         default:
  64           __kernel_sincosl (y[0], y[1], cosx, sinx, 1);
  65           *sinx = -*sinx;
  66           break;
  67         }
  68     }
  69 }
  70 weak_alias (__sincosl, sincosl)