sysdeps/ieee754/ldbl-128ibm/s_sincosl.c

   1 /* Compute sine and cosine of argument.
   2    Copyright (C) 1997-2019 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    <https://www.gnu.org/licenses/>.  */
  20
  21 #include <errno.h>
  22 #include <math.h>
  23
  24 #include <math_private.h>
  25 #include <math_ldbl_opt.h>
  26
  27 void
  28 __sincosl (long double x, long double *sinx, long double *cosx)
  29 {
  30   int64_t ix;
  31   double xhi;
  32
  33   /* High word of x. */
  34   xhi = ldbl_high (x);
  35   EXTRACT_WORDS64 (ix, xhi);
  36
  37   /* |x| ~< pi/4 */
  38   ix &= 0x7fffffffffffffffLL;
  39   if (ix <= 0x3fe921fb54442d10LL)
  40     __kernel_sincosl (x, 0.0L, sinx, cosx, 0);
  41   else if (ix >= 0x7ff0000000000000LL)
  42     {
  43       /* sin(Inf or NaN) is NaN */
  44       *sinx = *cosx = x - x;
  45       if (isinf (x))
  46         __set_errno (EDOM);
  47     }
  48   else
  49     {
  50       /* Argument reduction needed.  */
  51       long double y[2];
  52       int n;
  53
  54       n = __ieee754_rem_pio2l (x, y);
  55       switch (n & 3)
  56         {
  57         case 0:
  58           __kernel_sincosl (y[0], y[1], sinx, cosx, 1);
  59           break;
  60         case 1:
  61           __kernel_sincosl (y[0], y[1], cosx, sinx, 1);
  62           *cosx = -*cosx;
  63           break;
  64         case 2:
  65           __kernel_sincosl (y[0], y[1], sinx, cosx, 1);
  66           *sinx = -*sinx;
  67           *cosx = -*cosx;
  68           break;
  69         default:
  70           __kernel_sincosl (y[0], y[1], cosx, sinx, 1);
  71           *sinx = -*sinx;
  72           break;
  73         }
  74     }
  75 }
  76 long_double_symbol (libm, __sincosl, sincosl);