1/* k_cosf.c -- float version of k_cos.c
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3 */
4
5/*
6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8 *
9 * Developed at SunPro, a Sun Microsystems, Inc. business.
10 * Permission to use, copy, modify, and distribute this
11 * software is freely granted, provided that this notice
12 * is preserved.
13 * ====================================================
14 */
15
16#include "math.h"
17#include "math_private.h"
18
19static const float
20one =  1.0000000000e+00, /* 0x3f800000 */
21C1  =  4.1666667908e-02, /* 0x3d2aaaab */
22C2  = -1.3888889225e-03, /* 0xbab60b61 */
23C3  =  2.4801587642e-05, /* 0x37d00d01 */
24C4  = -2.7557314297e-07, /* 0xb493f27c */
25C5  =  2.0875723372e-09, /* 0x310f74f6 */
26C6  = -1.1359647598e-11; /* 0xad47d74e */
27
28float
29__kernel_cosf(float x, float y)
30{
31	float a,hz,z,r,qx;
32	int32_t ix;
33	GET_FLOAT_WORD(ix,x);
34	ix &= 0x7fffffff;			/* ix = |x|'s high word*/
35	z  = x*x;
36	r  = z*(C1+z*(C2+z*(C3+z*(C4+z*(C5+z*C6)))));
37	if(ix < 0x3e99999a) 			/* if |x| < 0.3 */
38	    return one - ((float)0.5*z - (z*r - x*y));
39	else {
40	    if(ix > 0x3f480000) {		/* x > 0.78125 */
41		qx = (float)0.28125;
42	    } else {
43	        SET_FLOAT_WORD(qx,ix-0x01000000);	/* x/4 */
44	    }
45	    hz = (float)0.5*z-qx;
46	    a  = one-qx;
47	    return a - (hz - (z*r-x*y));
48	}
49}
50