1 /* sf_cos.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 "fdlibm.h"
17 
18 #ifdef __STDC__
19 static const float one=1.0;
20 #else
21 static float one=1.0;
22 #endif
23 
24 #ifdef __STDC__
cosf(float x)25 	float cosf(float x)
26 #else
27 	float cosf(x)
28 	float x;
29 #endif
30 {
31 	float y[2],z=0.0;
32 	__int32_t n,ix;
33 
34 	GET_FLOAT_WORD(ix,x);
35 
36     /* |x| ~< pi/4 */
37 	ix &= 0x7fffffff;
38 	if(ix <= 0x3f490fd8) return __kernel_cosf(x,z);
39 
40     /* cos(Inf or NaN) is NaN */
41 	else if (!FLT_UWORD_IS_FINITE(ix)) return x-x;
42 
43     /* argument reduction needed */
44 	else {
45 	    n = __ieee754_rem_pio2f(x,y);
46 	    switch(n&3) {
47 		case 0: return  __kernel_cosf(y[0],y[1]);
48 		case 1: return -__kernel_sinf(y[0],y[1],1);
49 		case 2: return -__kernel_cosf(y[0],y[1]);
50 		default:
51 		        return  __kernel_sinf(y[0],y[1],1);
52 	    }
53 	}
54 }
55 
56 #ifdef _DOUBLE_IS_32BITS
57 
58 #ifdef __STDC__
cos(double x)59 	double cos(double x)
60 #else
61 	double cos(x)
62 	double x;
63 #endif
64 {
65 	return (double) cosf((float) x);
66 }
67 
68 #endif /* defined(_DOUBLE_IS_32BITS) */
69