1*c9945492SAndroid Build Coastguard Worker /* origin: FreeBSD /usr/src/lib/msun/src/k_cosf.c */
2*c9945492SAndroid Build Coastguard Worker /*
3*c9945492SAndroid Build Coastguard Worker * Conversion to float by Ian Lance Taylor, Cygnus Support, [email protected].
4*c9945492SAndroid Build Coastguard Worker * Debugged and optimized by Bruce D. Evans.
5*c9945492SAndroid Build Coastguard Worker */
6*c9945492SAndroid Build Coastguard Worker /*
7*c9945492SAndroid Build Coastguard Worker * ====================================================
8*c9945492SAndroid Build Coastguard Worker * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
9*c9945492SAndroid Build Coastguard Worker *
10*c9945492SAndroid Build Coastguard Worker * Developed at SunPro, a Sun Microsystems, Inc. business.
11*c9945492SAndroid Build Coastguard Worker * Permission to use, copy, modify, and distribute this
12*c9945492SAndroid Build Coastguard Worker * software is freely granted, provided that this notice
13*c9945492SAndroid Build Coastguard Worker * is preserved.
14*c9945492SAndroid Build Coastguard Worker * ====================================================
15*c9945492SAndroid Build Coastguard Worker */
16*c9945492SAndroid Build Coastguard Worker
17*c9945492SAndroid Build Coastguard Worker #include "libm.h"
18*c9945492SAndroid Build Coastguard Worker
19*c9945492SAndroid Build Coastguard Worker /* |cos(x) - c(x)| < 2**-34.1 (~[-5.37e-11, 5.295e-11]). */
20*c9945492SAndroid Build Coastguard Worker static const double
21*c9945492SAndroid Build Coastguard Worker C0 = -0x1ffffffd0c5e81.0p-54, /* -0.499999997251031003120 */
22*c9945492SAndroid Build Coastguard Worker C1 = 0x155553e1053a42.0p-57, /* 0.0416666233237390631894 */
23*c9945492SAndroid Build Coastguard Worker C2 = -0x16c087e80f1e27.0p-62, /* -0.00138867637746099294692 */
24*c9945492SAndroid Build Coastguard Worker C3 = 0x199342e0ee5069.0p-68; /* 0.0000243904487962774090654 */
25*c9945492SAndroid Build Coastguard Worker
__cosdf(double x)26*c9945492SAndroid Build Coastguard Worker float __cosdf(double x)
27*c9945492SAndroid Build Coastguard Worker {
28*c9945492SAndroid Build Coastguard Worker double_t r, w, z;
29*c9945492SAndroid Build Coastguard Worker
30*c9945492SAndroid Build Coastguard Worker /* Try to optimize for parallel evaluation as in __tandf.c. */
31*c9945492SAndroid Build Coastguard Worker z = x*x;
32*c9945492SAndroid Build Coastguard Worker w = z*z;
33*c9945492SAndroid Build Coastguard Worker r = C2+z*C3;
34*c9945492SAndroid Build Coastguard Worker return ((1.0+z*C0) + w*C1) + (w*z)*r;
35*c9945492SAndroid Build Coastguard Worker }
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