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74 lines
1.9 KiB
C
74 lines
1.9 KiB
C
/* Compute sine and cosine of argument.
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Copyright (C) 1997, 2000 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 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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<http://www.gnu.org/licenses/>. */
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#include <math.h>
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#include <math_private.h>
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void
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__sincosf (float x, float *sinx, float *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_FLOAT_WORD (ix, x);
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/* |x| ~< pi/4 */
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ix &= 0x7fffffff;
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if (ix <= 0x3f490fd8)
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{
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*sinx = __kernel_sinf (x, 0.0, 0);
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*cosx = __kernel_cosf (x, 0.0);
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}
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else if (ix>=0x7f800000)
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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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float y[2];
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int n;
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n = __ieee754_rem_pio2f (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_sinf (y[0], y[1], 1);
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*cosx = __kernel_cosf (y[0], y[1]);
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break;
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case 1:
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*sinx = __kernel_cosf (y[0], y[1]);
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*cosx = -__kernel_sinf (y[0], y[1], 1);
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break;
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case 2:
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*sinx = -__kernel_sinf (y[0], y[1], 1);
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*cosx = -__kernel_cosf (y[0], y[1]);
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break;
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default:
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*sinx = -__kernel_cosf (y[0], y[1]);
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*cosx = __kernel_sinf (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 (__sincosf, sincosf)
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