79 lines
2.0 KiB
C
79 lines
2.0 KiB
C
/* Compute sine and cosine of argument.
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Copyright (C) 1997 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
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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 Library General Public License as
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published by the Free Software Foundation; either version 2 of the
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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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Library General Public License for more details.
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You should have received a copy of the GNU Library General Public
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License along with the GNU C Library; see the file COPYING.LIB. If not,
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write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include <math.h>
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#include "math_private.h"
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void
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__sincos (double x, double *sinx, double *cosx)
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{
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int32_t ix;
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/* High word of x. */
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GET_HIGH_WORD (ix, x);
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/* |x| ~< pi/4 */
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ix &= 0x7fffffff;
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if (ix <= 0x3fe921fb)
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{
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*sinx = __kernel_sin (x, 0.0, 0);
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*cosx = __kernel_cos (x, 0.0);
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}
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else if (ix>=0x7ff00000)
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{
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/* sin(Inf or NaN) is NaN */
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*sinx = *cosx = x - x;
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}
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else
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{
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/* Argument reduction needed. */
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double y[2];
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int n;
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n = __ieee754_rem_pio2 (x, y);
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switch (n & 3)
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{
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case 0:
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*sinx = __kernel_sin (y[0], y[1], 1);
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*cosx = __kernel_cos (y[0], y[1]);
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break;
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case 1:
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*sinx = __kernel_cos (y[0], y[1]);
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*cosx = -__kernel_sin (y[0], y[1], 1);
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break;
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case 2:
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*sinx = -__kernel_sin (y[0], y[1], 1);
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*cosx = -__kernel_cos (y[0], y[1]);
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break;
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default:
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*sinx = -__kernel_cos (y[0], y[1]);
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*cosx = __kernel_sin (y[0], y[1], 1);
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break;
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}
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}
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}
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weak_alias (__sincos, sincos)
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#ifdef NO_LONG_DOUBLE
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strong_alias (__sincos, __sincosl)
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weak_alias (__sincos, sincosl)
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#endif
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