OpenLibm/src/e_sinhf.c
2016-03-13 21:07:55 -04:00

57 lines
1.5 KiB
C

/* e_sinhf.c -- float version of e_sinh.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#include "cdefs-compat.h"
//__FBSDID("$FreeBSD: src/lib/msun/src/e_sinhf.c,v 1.10 2011/10/21 06:28:47 das Exp $");
#include <openlibm_math.h>
#include "math_private.h"
static const float one = 1.0, shuge = 1.0e37;
OLM_DLLEXPORT float
__ieee754_sinhf(float x)
{
float t,h;
int32_t ix,jx;
GET_FLOAT_WORD(jx,x);
ix = jx&0x7fffffff;
/* x is INF or NaN */
if(ix>=0x7f800000) return x+x;
h = 0.5;
if (jx<0) h = -h;
/* |x| in [0,9], return sign(x)*0.5*(E+E/(E+1))) */
if (ix < 0x41100000) { /* |x|<9 */
if (ix<0x39800000) /* |x|<2**-12 */
if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */
t = expm1f(fabsf(x));
if(ix<0x3f800000) return h*((float)2.0*t-t*t/(t+one));
return h*(t+t/(t+one));
}
/* |x| in [9, logf(maxfloat)] return 0.5*exp(|x|) */
if (ix < 0x42b17217) return h*__ieee754_expf(fabsf(x));
/* |x| in [logf(maxfloat), overflowthresold] */
if (ix<=0x42b2d4fc)
return h*2.0F*__ldexp_expf(fabsf(x), -1);
/* |x| > overflowthresold, sinh(x) overflow */
return x*shuge;
}