1/* s_cosf.c -- float version of s_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
19float
20cosf(float x)
21{
22	float y[2],z=0.0;
23	int32_t n,ix;
24
25	GET_FLOAT_WORD(ix,x);
26
27    /* |x| ~< pi/4 */
28	ix &= 0x7fffffff;
29	if(ix <= 0x3f490fd8) {
30	    if(ix<0x39800000)			/* if x < 2**-12 */
31		if(((int)x)==0) return 1.0;	/* generate inexact */
32	    return __kernel_cosf(x,z);
33	}
34
35
36    /* cos(Inf or NaN) is NaN */
37	else if (ix>=0x7f800000) return x-x;
38
39    /* argument reduction needed */
40	else {
41	    n = __ieee754_rem_pio2f(x,y);
42	    switch(n&3) {
43		case 0: return  __kernel_cosf(y[0],y[1]);
44		case 1: return -__kernel_sinf(y[0],y[1],1);
45		case 2: return -__kernel_cosf(y[0],y[1]);
46		default:
47		        return  __kernel_sinf(y[0],y[1],1);
48	    }
49	}
50}
51DEF_STD(cosf);
52