glibc/sysdeps/libm-ieee754/e_sinh.c
Ulrich Drepper 6796bc807a Update.
1998-09-06 09:53 -0400  Zack Weinberg  <zack@rabi.phys.columbia.edu>

	* Makeconfig (+gccwarn): Remove -Wno-parentheses.

	* elf/dl-open.c: Quiet -Wparentheses warnings.
	* iconvdata/johab.c: Likewise.
	* iconvdata/uhc.c: Likewise.
	* inet/inet_net.c: Likewise.
	* io/fts.c: Likewise.
	* locale/newlocale.c: Likewise.
	* misc/getttyent.c: Likewise.
	* misc/mntent_r.c: Likewise.
	* misc/ttyslot.c: Likewise.
	* nscd/nscd_conf.c: Likewise.
	* nss/nsswitch.c: Likewise.
	* resolv/gethnamaddr.c: Likewise.
	* resolv/nsap_addr.c: Likewise.
	* resolv/res_debug.c: Likewise.
	* stdio-common/_itoa.c: Likewise.
	* stdlib/strtod.c: Likewise.
	* string/strverscmp.c: Likewise.
	* sunrpc/svc.c: Likewise.
	* sysdeps/libm-ieee754/e_cosh.c: Likewise.
	* sysdeps/libm-ieee754/e_gamma_r.c: Likewise.
	* sysdeps/libm-ieee754/e_sinh.c: Likewise.
	* sysdeps/posix/getaddrinfo.c: Likewise.

	* include/dlfcn.h: Likewise.
	* elf/dlfcn.h: Declare dladdr only for __USE_GNU.
	Define RTLD_DEFAULT.
1998-09-06 23:45:24 +00:00

87 lines
2.3 KiB
C

/* @(#)e_sinh.c 5.1 93/09/24 */
/*
* ====================================================
* 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.
* ====================================================
*/
#if defined(LIBM_SCCS) && !defined(lint)
static char rcsid[] = "$NetBSD: e_sinh.c,v 1.7 1995/05/10 20:46:13 jtc Exp $";
#endif
/* __ieee754_sinh(x)
* Method :
* mathematically sinh(x) if defined to be (exp(x)-exp(-x))/2
* 1. Replace x by |x| (sinh(-x) = -sinh(x)).
* 2.
* E + E/(E+1)
* 0 <= x <= 22 : sinh(x) := --------------, E=expm1(x)
* 2
*
* 22 <= x <= lnovft : sinh(x) := exp(x)/2
* lnovft <= x <= ln2ovft: sinh(x) := exp(x/2)/2 * exp(x/2)
* ln2ovft < x : sinh(x) := x*shuge (overflow)
*
* Special cases:
* sinh(x) is |x| if x is +INF, -INF, or NaN.
* only sinh(0)=0 is exact for finite x.
*/
#include "math.h"
#include "math_private.h"
#ifdef __STDC__
static const double one = 1.0, shuge = 1.0e307;
#else
static double one = 1.0, shuge = 1.0e307;
#endif
#ifdef __STDC__
double __ieee754_sinh(double x)
#else
double __ieee754_sinh(x)
double x;
#endif
{
double t,w,h;
int32_t ix,jx;
u_int32_t lx;
/* High word of |x|. */
GET_HIGH_WORD(jx,x);
ix = jx&0x7fffffff;
/* x is INF or NaN */
if(ix>=0x7ff00000) return x+x;
h = 0.5;
if (jx<0) h = -h;
/* |x| in [0,22], return sign(x)*0.5*(E+E/(E+1))) */
if (ix < 0x40360000) { /* |x|<22 */
if (ix<0x3e300000) /* |x|<2**-28 */
if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */
t = __expm1(fabs(x));
if(ix<0x3ff00000) return h*(2.0*t-t*t/(t+one));
return h*(t+t/(t+one));
}
/* |x| in [22, log(maxdouble)] return 0.5*exp(|x|) */
if (ix < 0x40862e42) return h*__ieee754_exp(fabs(x));
/* |x| in [log(maxdouble), overflowthresold] */
GET_LOW_WORD(lx,x);
if (ix<0x408633ce || ((ix==0x408633ce)&&(lx<=(u_int32_t)0x8fb9f87d))) {
w = __ieee754_exp(0.5*fabs(x));
t = h*w;
return t*w;
}
/* |x| > overflowthresold, sinh(x) overflow */
return x*shuge;
}