sysdeps/ieee754/ldbl-96/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.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <math.h>
  21
  22 #include <math_private.h>
  23
  24
  25 void
  26 __sincosl (long double x, long double *sinx, long double *cosx)
  27 {
  28   int32_t se, i0, i1 __attribute__ ((unused));
  29
  30   /* High word of x. */
  31   GET_LDOUBLE_WORDS (se, i0, i1, x);
  32
  33   /* |x| ~< pi/4 */
  34   se &= 0x7fff;
  35   if (se < 0x3ffe || (se == 0x3ffe && i0 <= 0xc90fdaa2))
  36     {
  37       *sinx = __kernel_sinl (x, 0.0, 0);
  38       *cosx = __kernel_cosl (x, 0.0);
  39     }
  40   else if (se == 0x7fff)
  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           *sinx = __kernel_sinl (y[0], y[1], 1);
  56           *cosx = __kernel_cosl (y[0], y[1]);
  57           break;
  58         case 1:
  59           *sinx = __kernel_cosl (y[0], y[1]);
  60           *cosx = -__kernel_sinl (y[0], y[1], 1);
  61           break;
  62         case 2:
  63           *sinx = -__kernel_sinl (y[0], y[1], 1);
  64           *cosx = -__kernel_cosl (y[0], y[1]);
  65           break;
  66         default:
  67           *sinx = -__kernel_cosl (y[0], y[1]);
  68           *cosx = __kernel_sinl (y[0], y[1], 1);
  69           break;
  70         }
  71     }
  72 }
  73 weak_alias (__sincosl, sincosl)