1/* e_sinhf.c -- float version of e_sinh.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: e_sinhf.c,v 1.6 1999/07/02 15:37:41 simonb Exp $");
19#endif
20
21#include "math.h"
22#include "math_private.h"
23
24static const float one = 1.0, shuge = 1.0e37;
25
26float
27__ieee754_sinhf(float x)
28{
29	float t,w,h;
30	int32_t ix,jx;
31
32	GET_FLOAT_WORD(jx,x);
33	ix = jx&0x7fffffff;
34
35    /* x is INF or NaN */
36	if(ix>=0x7f800000) return x+x;
37
38	h = 0.5;
39	if (jx<0) h = -h;
40    /* |x| in [0,22], return sign(x)*0.5*(E+E/(E+1))) */
41	if (ix < 0x41b00000) {		/* |x|<22 */
42	    if (ix<0x31800000) 		/* |x|<2**-28 */
43		if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */
44	    t = expm1f(fabsf(x));
45	    if(ix<0x3f800000) return h*((float)2.0*t-t*t/(t+one));
46	    return h*(t+t/(t+one));
47	}
48
49    /* |x| in [22, log(maxdouble)] return 0.5*exp(|x|) */
50	if (ix < 0x42b17180)  return h*__ieee754_expf(fabsf(x));
51
52    /* |x| in [log(maxdouble), overflowthresold] */
53	if (ix<=0x42b2d4fc) {
54	    w = __ieee754_expf((float)0.5*fabsf(x));
55	    t = h*w;
56	    return t*w;
57	}
58
59    /* |x| > overflowthresold, sinh(x) overflow */
60	return x*shuge;
61}
62