sysdeps/ieee754/ldbl-128ibm/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 #include <math_ldbl_opt.h>
  25
  26 void
  27 __sincosl (long double x, long double *sinx, long double *cosx)
  28 {
  29   int64_t ix;
  30   double xhi;
  31
  32   /* High word of x. */
  33   xhi = ldbl_high (x);
  34   EXTRACT_WORDS64 (ix, xhi);
  35
  36   /* |x| ~< pi/4 */
  37   ix &= 0x7fffffffffffffffLL;
  38   if (ix <= 0x3fe921fb54442d10LL)
  39     __kernel_sincosl (x, 0.0L, sinx, cosx, 0);
  40   else if (ix >= 0x7ff0000000000000LL)
  41     {
  42       /* sin(Inf or NaN) is NaN */
  43       *sinx = *cosx = x - x;
  44     }
  45   else
  46     {
  47       /* Argument reduction needed.  */
  48       long double y[2];
  49       int n;
  50
  51       n = __ieee754_rem_pio2l (x, y);
  52       switch (n & 3)
  53         {
  54         case 0:
  55           __kernel_sincosl (y[0], y[1], sinx, cosx, 1);
  56           break;
  57         case 1:
  58           __kernel_sincosl (y[0], y[1], cosx, sinx, 1);
  59           *cosx = -*cosx;
  60           break;
  61         case 2:
  62           __kernel_sincosl (y[0], y[1], sinx, cosx, 1);
  63           *sinx = -*sinx;
  64           *cosx = -*cosx;
  65           break;
  66         default:
  67           __kernel_sincosl (y[0], y[1], cosx, sinx, 1);
  68           *sinx = -*sinx;
  69           break;
  70         }
  71     }
  72 }
  73 long_double_symbol (libm, __sincosl, sincosl);