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      1 /* Compute sine and cosine of argument.
      2    Copyright (C) 1997-2018 Free Software Foundation, Inc.
      3    This file is part of the GNU C Library.
      4    Contributed by Ulrich Drepper <drepper (at) cygnus.com>, 1997 and
      5 		  Jakub Jelinek <jj (at) 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 "quadmath-imp.h"
     22 
     23 void
     24 sincosq (__float128 x, __float128 *sinx, __float128 *cosx)
     25 {
     26   int64_t ix;
     27 
     28   /* High word of x. */
     29   GET_FLT128_MSW64 (ix, x);
     30 
     31   /* |x| ~< pi/4 */
     32   ix &= 0x7fffffffffffffffLL;
     33   if (ix <= 0x3ffe921fb54442d1LL)
     34     __quadmath_kernel_sincosq (x, 0, sinx, cosx, 0);
     35   else if (ix >= 0x7fff000000000000LL)
     36     {
     37       /* sin(Inf or NaN) is NaN */
     38       *sinx = *cosx = x - x;
     39       if (isinfq (x))
     40 	errno = EDOM;
     41     }
     42   else
     43     {
     44       /* Argument reduction needed.  */
     45       __float128 y[2];
     46       int n;
     47 
     48       n = __quadmath_rem_pio2q (x, y);
     49       switch (n & 3)
     50 	{
     51 	case 0:
     52 	  __quadmath_kernel_sincosq (y[0], y[1], sinx, cosx, 1);
     53 	  break;
     54 	case 1:
     55 	  __quadmath_kernel_sincosq (y[0], y[1], cosx, sinx, 1);
     56 	  *cosx = -*cosx;
     57 	  break;
     58 	case 2:
     59 	  __quadmath_kernel_sincosq (y[0], y[1], sinx, cosx, 1);
     60 	  *sinx = -*sinx;
     61 	  *cosx = -*cosx;
     62 	  break;
     63 	default:
     64 	  __quadmath_kernel_sincosq (y[0], y[1], cosx, sinx, 1);
     65 	  *sinx = -*sinx;
     66 	  break;
     67 	}
     68     }
     69 }
     70