diff options
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_tanhl.c')
-rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/s_tanhl.c | 87 |
1 files changed, 0 insertions, 87 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_tanhl.c b/sysdeps/ieee754/ldbl-128ibm/s_tanhl.c deleted file mode 100644 index e6457a1c1c..0000000000 --- a/sysdeps/ieee754/ldbl-128ibm/s_tanhl.c +++ /dev/null @@ -1,87 +0,0 @@ -/* @(#)s_tanh.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: s_tanh.c,v 1.7 1995/05/10 20:48:22 jtc Exp $"; -#endif - -/* Tanh(x) - * Return the Hyperbolic Tangent of x - * - * Method : - * x -x - * e - e - * 0. tanh(x) is defined to be ----------- - * x -x - * e + e - * 1. reduce x to non-negative by tanh(-x) = -tanh(x). - * 2. 0 <= x <= 2**-57 : tanh(x) := x*(one+x) - * -t - * 2**-57 < x <= 1 : tanh(x) := -----; t = expm1(-2x) - * t + 2 - * 2 - * 1 <= x <= 40.0 : tanh(x) := 1- ----- ; t=expm1(2x) - * t + 2 - * 40.0 < x <= INF : tanh(x) := 1. - * - * Special cases: - * tanh(NaN) is NaN; - * only tanh(0)=0 is exact for finite argument. - */ - -#include <float.h> -#include <math.h> -#include <math_private.h> -#include <math_ldbl_opt.h> - -static const long double one=1.0L, two=2.0L, tiny = 1.0e-300L; - -long double __tanhl(long double x) -{ - long double t,z; - int64_t jx,ix; - double xhi; - - /* High word of |x|. */ - xhi = ldbl_high (x); - EXTRACT_WORDS64 (jx, xhi); - ix = jx&0x7fffffffffffffffLL; - - /* x is INF or NaN */ - if(ix>=0x7ff0000000000000LL) { - if (jx>=0) return one/x+one; /* tanh(+-inf)=+-1 */ - else return one/x-one; /* tanh(NaN) = NaN */ - } - - /* |x| < 40 */ - if (ix < 0x4044000000000000LL) { /* |x|<40 */ - if (ix == 0) - return x; /* x == +-0 */ - if (ix<0x3c60000000000000LL) /* |x|<2**-57 */ - { - math_check_force_underflow (x); - return x; /* tanh(small) = small */ - } - if (ix>=0x3ff0000000000000LL) { /* |x|>=1 */ - t = __expm1l(two*fabsl(x)); - z = one - two/(t+two); - } else { - t = __expm1l(-two*fabsl(x)); - z= -t/(t+two); - } - /* |x| > 40, return +-1 */ - } else { - z = one - tiny; /* raised inexact flag */ - } - return (jx>=0)? z: -z; -} -long_double_symbol (libm, __tanhl, tanhl); |