diff options
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_asinhl.c')
-rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/s_asinhl.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_asinhl.c b/sysdeps/ieee754/ldbl-128ibm/s_asinhl.c new file mode 100644 index 0000000000..d1b63bb909 --- /dev/null +++ b/sysdeps/ieee754/ldbl-128ibm/s_asinhl.c @@ -0,0 +1,67 @@ +/* @(#)s_asinh.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_asinh.c,v 1.9 1995/05/12 04:57:37 jtc Exp $"; +#endif + +/* asinh(x) + * Method : + * Based on + * asinh(x) = sign(x) * log [ |x| + sqrt(x*x+1) ] + * we have + * asinh(x) := x if 1+x*x=1, + * := sign(x)*(log(x)+ln2)) for large |x|, else + * := sign(x)*log(2|x|+1/(|x|+sqrt(x*x+1))) if|x|>2, else + * := sign(x)*log1p(|x| + x^2/(1 + sqrt(1+x^2))) + */ + +#include "math.h" +#include "math_private.h" +#include <math_ldbl_opt.h> + +#ifdef __STDC__ +static const long double +#else +static long double +#endif +one = 1.00000000000000000000e+00L, /* 0x3ff0000000000000, 0 */ +ln2 = 0.6931471805599453094172321214581766L, /* 0x3fe62e42fefa39ef, 0x3c7abc9e3b398040 */ +huge= 1.00000000000000000000e+300L; + +#ifdef __STDC__ + long double __asinhl(long double x) +#else + long double __asinhl(x) + long double x; +#endif +{ + long double t,w; + int64_t hx,ix; + GET_LDOUBLE_MSW64(hx,x); + ix = hx&0x7fffffffffffffffLL; + if(ix>=0x7ff0000000000000LL) return x+x; /* x is inf or NaN */ + if(ix< 0x3e20000000000000LL) { /* |x|<2**-29 */ + if(huge+x>one) return x; /* return x inexact except 0 */ + } + if(ix>0x41b0000000000000LL) { /* |x| > 2**28 */ + w = __ieee754_logl(fabs(x))+ln2; + } else if (ix>0x4000000000000000LL) { /* 2**28 > |x| > 2.0 */ + t = fabs(x); + w = __ieee754_logl(2.0*t+one/(__ieee754_sqrtl(x*x+one)+t)); + } else { /* 2.0 > |x| > 2**-29 */ + t = x*x; + w =__log1pl(fabsl(x)+t/(one+__ieee754_sqrtl(one+t))); + } + if(hx>0) return w; else return -w; +} +long_double_symbol (libm, __asinhl, asinhl); |