sysdeps/ieee754/ldbl-128/s_sincosl.c

   1 /* Compute sine and cosine of argument.
   2    Copyright (C) 1997, 1999 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, 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
  24 #include "math_private.h"
  25
  26 void
  27 __sincosl (long double x, long double *sinx, long double *cosx)
  28 {
  29   int64_t ix;
  30
  31   /* High word of x. */
  32   GET_LDOUBLE_MSW64 (ix, x);
  33
  34   /* |x| ~< pi/4 */
  35   ix &= 0x7fffffffffffffffLL;
  36   if (ix <= 0x3ffe921fb54442d1LL)
  37     __kernel_sincosl (x, 0.0L, sinx, cosx, 0);
  38   else if (ix >= 0x7fff000000000000LL)
  39     {
  40       /* sin(Inf or NaN) is NaN */
  41       *sinx = *cosx = x - x;
  42     }
  43   else
  44     {
  45       /* Argument reduction needed.  */
  46       long double y[2];
  47       int n;
  48
  49       n = __ieee754_rem_pio2l (x, y);
  50       switch (n & 3)
  51         {
  52         case 0:
  53           __kernel_sincosl (y[0], y[1], sinx, cosx, 1);
  54           break;
  55         case 1:
  56           __kernel_sincosl (y[0], y[1], cosx, sinx, 1);
  57           *cosx = -*cosx;
  58           break;
  59         case 2:
  60           __kernel_sincosl (y[0], y[1], sinx, cosx, 1);
  61           *sinx = -*sinx;
  62           *cosx = -*cosx;
  63           break;
  64         default:
  65           __kernel_sincosl (y[0], y[1], cosx, sinx, 1);
  66           *sinx = -*sinx;
  67           break;
  68         }
  69     }
  70 }
  71 weak_alias (__sincosl, sincosl)