Rich Felker | b69f695 | 2012-03-13 01:17:53 -0400 | [diff] [blame] | 1 | #include "libm.h" |
| 2 | |
| 3 | #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024 |
| 4 | long double asinhl(long double x) |
| 5 | { |
| 6 | return asinh(x); |
| 7 | } |
| 8 | #elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384 |
Szabolcs Nagy | 482ccd2 | 2012-12-11 23:06:20 +0100 | [diff] [blame] | 9 | /* asinh(x) = sign(x)*log(|x|+sqrt(x*x+1)) ~= x - x^3/6 + o(x^5) */ |
Rich Felker | b69f695 | 2012-03-13 01:17:53 -0400 | [diff] [blame] | 10 | long double asinhl(long double x) |
| 11 | { |
Szabolcs Nagy | aa0c4a2 | 2013-09-04 15:54:02 +0000 | [diff] [blame] | 12 | union ldshape u = {x}; |
Szabolcs Nagy | 482ccd2 | 2012-12-11 23:06:20 +0100 | [diff] [blame] | 13 | unsigned e = u.i.se & 0x7fff; |
| 14 | unsigned s = u.i.se >> 15; |
Rich Felker | b69f695 | 2012-03-13 01:17:53 -0400 | [diff] [blame] | 15 | |
Szabolcs Nagy | 482ccd2 | 2012-12-11 23:06:20 +0100 | [diff] [blame] | 16 | /* |x| */ |
| 17 | u.i.se = e; |
| 18 | x = u.f; |
| 19 | |
| 20 | if (e >= 0x3fff + 32) { |
| 21 | /* |x| >= 0x1p32 or inf or nan */ |
| 22 | x = logl(x) + 0.693147180559945309417232121458176568L; |
| 23 | } else if (e >= 0x3fff + 1) { |
| 24 | /* |x| >= 2 */ |
| 25 | x = logl(2*x + 1/(sqrtl(x*x+1)+x)); |
| 26 | } else if (e >= 0x3fff - 32) { |
| 27 | /* |x| >= 0x1p-32 */ |
| 28 | x = log1pl(x + x*x/(sqrtl(x*x+1)+1)); |
| 29 | } else { |
| 30 | /* |x| < 0x1p-32, raise inexact if x!=0 */ |
Szabolcs Nagy | c6383b7 | 2012-12-16 20:28:43 +0100 | [diff] [blame] | 31 | FORCE_EVAL(x + 0x1p120f); |
Rich Felker | b69f695 | 2012-03-13 01:17:53 -0400 | [diff] [blame] | 32 | } |
Szabolcs Nagy | 482ccd2 | 2012-12-11 23:06:20 +0100 | [diff] [blame] | 33 | return s ? -x : x; |
Rich Felker | b69f695 | 2012-03-13 01:17:53 -0400 | [diff] [blame] | 34 | } |
Szabolcs Nagy | f4e4632 | 2015-03-10 20:01:20 +0000 | [diff] [blame] | 35 | #elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384 |
| 36 | // TODO: broken implementation to make things compile |
| 37 | long double asinhl(long double x) |
| 38 | { |
| 39 | return asinh(x); |
| 40 | } |
Rich Felker | b69f695 | 2012-03-13 01:17:53 -0400 | [diff] [blame] | 41 | #endif |