xref: /freebsd/lib/msun/src/k_sincosf.h (revision 6580f5c38dd5b01aeeaed16b370f1a12423437f0)
1 /*-
2  * ====================================================
3  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
4  *
5  * Developed at SunPro, a Sun Microsystems, Inc. business.
6  * Permission to use, copy, modify, and distribute this
7  * software is freely granted, provided that this notice
8  * is preserved.
9  * ====================================================
10  *
11  * k_sinf.c and k_cosf.c merged by Steven G. Kargl.
12  */
13 
14 /* |sin(x)/x - s(x)| < 2**-37.5 (~[-4.89e-12, 4.824e-12]). */
15 static const double
16 S1 = -0x15555554cbac77.0p-55,	/* -0.166666666416265235595 */
17 S2 =  0x111110896efbb2.0p-59,	/*  0.0083333293858894631756 */
18 S3 = -0x1a00f9e2cae774.0p-65,	/* -0.000198393348360966317347 */
19 S4 =  0x16cd878c3b46a7.0p-71;	/*  0.0000027183114939898219064 */
20 
21 /* |cos(x) - c(x)| < 2**-34.1 (~[-5.37e-11, 5.295e-11]). */
22 static const double
23 C0  = -0x1ffffffd0c5e81.0p-54,	/* -0.499999997251031003120 */
24 C1  =  0x155553e1053a42.0p-57,	/*  0.0416666233237390631894 */
25 C2  = -0x16c087e80f1e27.0p-62,	/* -0.00138867637746099294692 */
26 C3  =  0x199342e0ee5069.0p-68;	/*  0.0000243904487962774090654 */
27 
28 static inline void
29 __kernel_sincosdf(double x, float *sn, float *cs)
30 {
31 	double r, s, w, z;
32 
33 	z = x * x;
34 	w = z * z;
35 	r = S3 + z * S4;
36 	s = z * x;
37 	*sn = (x + s * (S1 + z * S2)) + s * w * r;
38 	r = C2 + z * C3;
39 	*cs = ((1 + z * C0) + w * C1) + (w * z) * r;
40 }
41