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111 lines
2.4 KiB
C
111 lines
2.4 KiB
C
/* Compute sine and cosine of argument.
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Copyright (C) 1997-2024 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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#include <errno.h>
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#include <math.h>
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#include <math_private.h>
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#include <fenv_private.h>
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#include <math-underflow.h>
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#include <libm-alias-double.h>
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#ifndef SECTION
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# define SECTION
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#endif
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#define IN_SINCOS
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#include "s_sin.c"
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void
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SECTION
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__sincos (double x, double *sinx, double *cosx)
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{
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mynumber u;
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int k;
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SET_RESTORE_ROUND_53BIT (FE_TONEAREST);
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u.x = x;
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k = u.i[HIGH_HALF] & 0x7fffffff;
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if (k < 0x400368fd)
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{
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double a, da, y;
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/* |x| < 2^-27 => cos (x) = 1, sin (x) = x. */
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if (k < 0x3e400000)
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{
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if (k < 0x3e500000)
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math_check_force_underflow (x);
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*sinx = x;
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*cosx = 1.0;
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return;
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}
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/* |x| < 0.855469. */
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else if (k < 0x3feb6000)
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{
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*sinx = do_sin (x, 0);
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*cosx = do_cos (x, 0);
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return;
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}
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/* |x| < 2.426265. */
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y = hp0 - fabs (x);
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a = y + hp1;
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da = (y - a) + hp1;
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*sinx = copysign (do_cos (a, da), x);
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*cosx = do_sin (a, da);
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return;
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}
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/* |x| < 2^1024. */
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if (k < 0x7ff00000)
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{
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double a, da, xx;
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unsigned int n;
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/* If |x| < 105414350 use simple range reduction. */
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n = k < 0x419921FB ? reduce_sincos (x, &a, &da) : __branred (x, &a, &da);
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n = n & 3;
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if (n == 1 || n == 2)
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{
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a = -a;
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da = -da;
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}
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if (n & 1)
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{
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double *temp = cosx;
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cosx = sinx;
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sinx = temp;
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}
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*sinx = do_sin (a, da);
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xx = do_cos (a, da);
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*cosx = (n & 2) ? -xx : xx;
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return;
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}
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if (isinf (x))
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__set_errno (EDOM);
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*sinx = *cosx = x / x;
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}
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#ifndef __sincos
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libm_alias_double (__sincos, sincos)
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#endif
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