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 <sys/cdefs.h>
17 #if defined(LIBM_SCCS) && !defined(lint)
18 __RCSID("$NetBSD: s_cosf.c,v 1.10 2024/05/08 01:40:27 riastradh Exp $");
19 #endif
20
21 #include "namespace.h"
22 #include "math.h"
23 #include "math_private.h"
24
__weak_alias(cosf,_cosf)25 __weak_alias(cosf, _cosf)
26
27 float
28 cosf(float x)
29 {
30 float y[2],z=0.0;
31 int32_t n,ix;
32
33 GET_FLOAT_WORD(ix,x);
34
35 /* |x| ~< pi/4 */
36 ix &= 0x7fffffff;
37 if(ix <= 0x3f490fd8) return __kernel_cosf(x,z);
38
39 /* cos(Inf or NaN) is NaN */
40 else if (ix>=0x7f800000) return x-x;
41
42 /* argument reduction needed */
43 else {
44 n = __ieee754_rem_pio2f(x,y);
45 switch(n&3) {
46 case 0: return __kernel_cosf(y[0],y[1]);
47 case 1: return -__kernel_sinf(y[0],y[1],1);
48 case 2: return -__kernel_cosf(y[0],y[1]);
49 default:
50 return __kernel_sinf(y[0],y[1],1);
51 }
52 }
53 }
54