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 <float.h>
17#include <math.h>
18#include <math-narrow-eval.h>
19#include <math_private.h>
20#include <math-underflow.h>
21#include <libm-alias-finite.h>
22
23static const float one = 1.0, shuge = 1.0e37;
24
25float
26__ieee754_sinhf(float x)
27{
28 float t,w,h;
29 int32_t ix,jx;
30
31 GET_FLOAT_WORD(jx,x);
32 ix = jx&0x7fffffff;
33
34 /* x is INF or NaN */
35 if(__builtin_expect(ix>=0x7f800000, 0)) return x+x;
36
37 h = 0.5;
38 if (jx<0) h = -h;
39 /* |x| in [0,22], return sign(x)*0.5*(E+E/(E+1))) */
40 if (ix < 0x41b00000) { /* |x|<22 */
41 if (__builtin_expect(ix<0x31800000, 0)) { /* |x|<2**-28 */
42 math_check_force_underflow (x);
43 if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */
44 }
45 t = __expm1f(fabsf(x));
46 if(ix<0x3f800000) return h*((float)2.0*t-t*t/(t+one));
47 return h*(t+t/(t+one));
48 }
49
50 /* |x| in [22, log(maxdouble)] return 0.5*exp(|x|) */
51 if (ix < 0x42b17180) return h*__ieee754_expf(fabsf(x));
52
53 /* |x| in [log(maxdouble), overflowthresold] */
54 if (ix<=0x42b2d4fc) {
55 w = __ieee754_expf((float)0.5*fabsf(x));
56 t = h*w;
57 return t*w;
58 }
59
60 /* |x| > overflowthresold, sinh(x) overflow */
61 return math_narrow_eval (x*shuge);
62}
63libm_alias_finite (__ieee754_sinhf, __sinhf)
64