1/* s_tanf.c -- float version of s_tan.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#if defined(LIBM_SCCS) && !defined(lint)
17static char rcsid[] = "$NetBSD: s_tanf.c,v 1.4 1995/05/10 20:48:20 jtc Exp $";
18#endif
19
20#include <errno.h>
21#include <math.h>
22#include <math_private.h>
23
24float __tanf(float x)
25{
26 float y[2],z=0.0;
27 int32_t n, ix;
28
29 GET_FLOAT_WORD(ix,x);
30
31 /* |x| ~< pi/4 */
32 ix &= 0x7fffffff;
33 if(ix <= 0x3f490fda) return __kernel_tanf(x,z,1);
34
35 /* tan(Inf or NaN) is NaN */
36 else if (ix>=0x7f800000) {
37 if (ix==0x7f800000)
38 __set_errno (EDOM);
39 return x-x; /* NaN */
40 }
41
42 /* argument reduction needed */
43 else {
44 n = __ieee754_rem_pio2f(x,y);
45 return __kernel_tanf(y[0],y[1],1-((n&1)<<1)); /* 1 -- n even
46 -1 -- n odd */
47 }
48}
49weak_alias (__tanf, tanf)
50